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Sample records for caprolactam production phase

  1. Caprolactam

    Integrated Risk Information System (IRIS)

    Caprolactam ; CASRN 105 - 60 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  2. Caprolactam production by direct solar flux

    SciTech Connect

    Talukdar, J.; Wong, E.H.S.; Mathur, V.K. )

    1991-01-01

    The use of solar energy for the photonitrozation of cyclohexane for the production of cyclohexanone oxime hydrochloride, an intermediate for the manufacture of caprolactam, is discussed. Experimental results show the technical feasibility of such a reaction in the presence of radiation of wavelength 350-550 nm simulating sunlight.

  3. A biological/chemical process for reduced waste and energy consumption, Caprolactam production: Phase 1, Select microorganisms and demonstrate feasibility. Final report

    SciTech Connect

    St.Martin, E.J.

    1995-08-01

    A novel biological/chemical process for converting cyclohexane into caprolactam was investigated. Microorganisms in a bioreactor would be used to convert cyclohexane into caprolactone followed by chemical synthesis of caprolactam using ammonia. The proposed bioprocess would be more energy efficient and reduce byproducts and wastes that are generated by the current chemical process. We have been successful in isolating from natural soil and water samples two microorganisms that can utilize cyclohexane as a sole source of carbon and energy for growth. These microorganisms were shown to have the correct metabolic intermediates and enzymes to convert cyclohexane into cyclohexanol, cyclohexanone and caprolactone. Genetic techniques to create and select for caprolactone hydrolase negative-mutants are being developed. These blocked-mutants will be used to convert cyclohexane into caprolactone but, because of the block, be unable to metabolize the caprolactone further and excrete it as a final end product.

  4. Uptake of caprolactam and its influence on growth and oxygen production of Desmodesmus quadricauda algae.

    PubMed

    Kalinová, Jana Pexová; Tříska, Jan; Vrchotová, Naděžda; Novák, Jan

    2016-06-01

    The consumption of polyamides produced from caprolactam is increasing continuously, and for that reason the danger of environmental contamination by this lactam is also rising. This study's aim was to evaluate the influence of caprolactam on the growth and oxygen production of the green alga Desmodesmus quadricauda and on caprolactam uptake by this alga. The presence of caprolactam in water was observed to cause the algae significantly to increase its oxygen production. Caprolactam concentration of 5,000 mg/L stopped algae growth after 6 days and influenced coenobia structure (seen as disappearance of pyrenoids, deformation of cells) but did not decrease the number of cells in the coenobia. Caprolactam uptake is probably passive but relatively rapid. Maximum concentration in the algae was reached after 18-24 h. PMID:26985739

  5. A biological/chemical process for reduced waste and energy consumption: caprolactam production. Final report

    SciTech Connect

    1996-05-01

    A biological/chemical process for converting cyclohexane into caprolactam was investigated: microorganisms in a bioreactor would be used to convert cyclohexane into caprolactone followed by chemical synthesis of caprolactam using ammonia. Four microorganisms were isolated from natural soil and water, that can utilize cyclohexane as a sole source of C and energy for growth. They were shown to have the correct metabolic intermediates and enzymes to convert cyclohexane into cyclohexanol, cyclohexanone, and caprolactone. Genetic techniques to create and select for caprolactone hydrolase negative-mutants were developed; those are used to convert cyclohexane into caprolactone but, because of the block, are unable to metabolize the caprolactone further. Because of a new nylon carpet reycle process and the long time frame for a totally new bioprocess, a limited study was done to evaluate whether a simplified bioprocess to convert cyclohexanol into cyclohexanone or caprolactone was feasible; growth rates and key enzyme levels were measured in a collection of microorganisms that metabolize cyclohexanol to determine if the bioactivity is high enough to support an economical cyclohexanol bioprocess. Although these microorganisms had sufficient bioactivity, they could tolerate only low levels (<1%) of cyclohexanol and thus are not suitable for developing a cost effective bioprocess because of the high cost of dilute product recovery.

  6. Purification of caprolactam from recycled nylon

    SciTech Connect

    Moens, L.

    1999-07-06

    A method is disclosed of removing 1,11-diamino-6-undecanone from the pyrolysis product of nylon comprising: (a) pyrolyzing nylon-6 to form a pyrolyzate containing a caprolactam mixture; (b) dissolving the caprolactam mixture in a solvent to form a solution; (c) passing carbon dioxide gas through the solution to form a precipitate; (d) removing the precipitate from the solution; and (e) recovering the purified caprolactam from the solution. 3 figs.

  7. Purification of caprolactam from recycled nylon

    SciTech Connect

    Moens, Luc

    1999-01-01

    A method of removing 1,11-diamino-6-undecanone from the pyrolysis product of nylon comprising: a) pyrolyzing nylon-6 to form a pyrolyzate containing a caprolactam mixture; b) dissolving the caprolactam mixture in a solvent to form a solution; c) passing carbon dioxide gas through the solution to form a precipitate; d) removing the precipitate from the solution; and e) recovering the purified caprolactam from the solution.

  8. Reversible flocculation of silica across the phase boundary of poly(vinyl caprolactam) in aqueous solution.

    PubMed

    Qiu, Q; Pethica, B A; Somasundaran, P

    2005-12-20

    The colloid stability of silica dispersions in water in the presence of poly(vinyl caprolactam) (PVCAP) has been studied below and above the lower consolute temperature (LCT) of its solutions. The dispersion sediments slowly without PVCAP in the temperature range studied (26-40 degrees C) or with PVCAP below the LCT ( approximately 30 degrees C). In contrast, with PVCAP above the LCT, rapid flocculation occurs at acid pH, with re-dispersal on cooling. Reversible flocculation is also obtained above the LCT by cycling the pH from alkaline to acid and back. The flocculation observed above the LCT may also be regarded as heterocoagulation between the silica particles and the aggregates of the polymer. PMID:16342979

  9. GENETIC TOXICOLOGY OF BENZOIN AND CAPROLACTAM

    EPA Science Inventory

    Based on animal carcinogenesis studies, benzoin and caprolactam have been classified as noncarcinogens. he genetic toxicity of both compounds has been thoroughly evaluated in short-term in vitro bioassays. enetic activity profiles and corresponding data listings and summaries are...

  10. Allylic Oxidations Catalyzed by Dirhodium Caprolactamate via Aqueous tert-Butyl Hydroperoxide: The Role of the tert-Butylperoxy Radical

    PubMed Central

    McLaughlin, Emily C.; Choi, Hojae; Wang, Kan; Chiou, Grace; Doyle, Michael P.

    2009-01-01

    Dirhodium(II) caprolactamate exhibits optimal efficiency for the production of the tert-butylperoxy radical, which is a selective reagent for hydrogen atom abstraction. These oxidation reactions occur with aqueous tert-butyl hydroperoxide (TBHP) without rapid hydrolysis of the caprolactamate ligands on dirhodium. Allylic oxidations of enones yield the corresponding enedione in moderate to high yields, and applications include allylic oxidations of steroidal enones. Although methylene oxidation to a ketone is more effective, methyl oxidation to a carboxylic acid can also be achieved. The superior efficiency of dirhodium(II) caprolactamate as a catalyst for allylic oxidations by TBHP (mol % catalyst, % conversion) is described in comparative studies with other metal catalysts that are also reported to be effective for allylic oxidations. That different catalysts produce essentially the same mixture of products with the same relative yields suggests that the catalyst is not involved in product forming steps. Mechanistic implications arising from studies of allylic oxidation with enones provide new insights into factors that control product formation. A previously undisclosed disproportionation pathway, catalyzed by the tert-butoxy radical, of mixed peroxides for the formation of ketone products via allylic oxidation has been uncovered. PMID:19072696

  11. Verification of presence of caprolactam in sprouted achenes of Fagopyrum esculentum Moench and its influence on plant phenolic compound content.

    PubMed

    Kalinová, Jana P; Tříska, Jan; Vrchotová, Naděžda; Moos, Martin

    2014-08-15

    The presence of caprolactam, a precursor of Nylon-6, among those synthetic polymers which are widely-spread throughout the environment, could be the reason for its being found in plants. The aim of this work was to confirm the previously described presence of caprolactam in dry and sprouted achenes, as well as in achene exudates of common buckwheat (Fagopyrum esculentum Moench). When the lyophilized sprouted and dry buckwheat achenes, along with exudates from growth experiments, with caprolactam-free medium were analysed by HPLC, no caprolactam was found. After addition of caprolactam into the growth medium, we confirmed the uptake of caprolactam in the lyophilized sprouted buckwheat achenes. The uptake of caprolactam is also a function of light conditions during the growth experiments. Caprolactam also inhibits the content of phenolic compounds; especially rutin, vitexin, isovitexin, orientin, and homoorientin in buckwheat plants. PMID:24679794

  12. Tensile Properties of Poly (N-vinyl caprolactam) Gels

    NASA Technical Reports Server (NTRS)

    Morgret, Leslie D.; Hinkley, Jeffrey A.

    2004-01-01

    N-vinyl caprolactam was copolymerized with ethylene glycol dimethacrylate using a free-radical initiator in alcohol/water solution. The resulting gels were thermally-responsive in water, undergoing an approximate fivefold reversible volume shrinkage between room temperature and ca. 50 C. Tensile testing showed that the stress-strain behavior was qualitatively different in the collapsed state above the temperature-induced transition. At the higher temperature, gels were stiffer, more ductile, and showed greater time dependence. Implications for the design of gel actuators are briefly discussed.

  13. Economic evaluation and comparison of the industrial photosynthesis of {var_epsilon}-caprolactam via solar or lamp operated photooximation of cyclohexane

    SciTech Connect

    Sattler, C.; Mueller, F.J.; Riffelmann, K.J.; Ortner, J.; Funken, K.H.

    1999-07-01

    A solar photochemical plant was drawn up for the manufacture of {var_epsilon}-caprolactam which is the base chemical for nylon-6. For the design and for the calculation of costs the lamp operated concept of Toray Ltd. was adapted to solar requirements. In a base case a unit with a capacity of 10,000 t/a was considered. Using that concept and economic evaluation was made to check the cost of solar production against the equivalent lamp-operated process. The results of the economic calculations suggest that solar production of {var_epsilon}-caprolactam may be profitable and large areas in the world are suitable for industrial solar photochemistry.

  14. Denitrification with epsilon-caprolactam by acclimated mixed culture and by pure culture of bacteria isolated from polyacrylonitrile fibre manufactured wastewater treatment system.

    PubMed

    Lee, C M; Wang, C C

    2004-01-01

    The aim of this study is to isolate denitrifying bacteria utilizing epsilon-caprolactam as the substrate, from a polyacrylonitrile fibre manufactured wastewater treatment system. The aim is also to compare the performance of PAN (polyacrylonitrile) mixed bacteria cultures acclimated to epsilon-caprolactam and isolated pure strain for treating different initial epsilon-caprolactam concentrations from synthetic wastewater under anoxic conditions. The result showed that the PAN mixed bacteria cultures acclimated to epsilon-caprolactam could utilize 1538.5 mg/l of epsilon-caprolactam as a substrate for denitrification. Sufficient time and about 2200 mg/l of nitrate were necessary for the complete epsilon-caprolactam removal. Paracoccus thiophilus was isolated from the polyacrylonitrile fibre manufactured wastewater treatment system and it could utilize 1722.5 mg/l of epsilon-caprolactam as a substrate for denitrification. About 3500 mg/l of nitrate was necessary for the complete removal of epsilon-caprolactam. When the initial epsilon-caprolactam concentration was below 784.3 mg/l, the removal efficiency of epsilon-caprolactam by Paracoccus thiophilus was better than that for the PAN mixed bacteria cultures. The growth of Paracoccus thiophilus was better. However, when the initial epsilon-caprolactam concentration was as high as 1445.8 mg/l, both the epsilon-caprolactam removal efficiency by Paracoccus thiophilus and Paracoccus thiophilus specific growth rate were similar to the PAN mixed bacteria cultures. PMID:15137443

  15. [Bacteria that degrade low-molecular linear epsilon-caprolactam olygomers].

    PubMed

    Esikova, T Z; Akatova, E V; Taran, S A

    2014-01-01

    Five bacterial strains with the unique ability to utilize low-molecular linear caprolactam olygomers (nylon olygomers) were isolated from soil samples contaminated with industrial wastes of epsilon-caprolactam. Based on the properties studied and also on the analysis of 16S rRNA gene nucleotide sequences, the strains BS2,BS3, BS9, BS38, and BS57 were classified to the general Arthrobacter, Brevibacterium, Microbacteriun, Gulosibacter, and Achromobacter, respectively. All of the strains also utilized 6-aminohexanoic and adipic acids, which are intermidiates of the epsilon-caprolactam catabolism. This indirectly points to the fact that degradation of olygomers in these bacteria occurs via the monomer degradation pathway. The BS9 and BS57 strains utilized only olygomers of the epsilon-caprolactam, while BS2, BS3, and BS38 also degraded epsilon-caprolactam and its homologs, enantolactam and caprylolactam, which differentiates the latter from the previously known degraders of olygomers and suggests the presence in these strains of enzymes with lactam hydrolase activity, in addition to 6-aminohexanoate-dimer hydrolase. PMID:25707105

  16. Catalytic conversion of γ-valerolactone to ε-caprolactam: towards nylon from renewable feedstock.

    PubMed

    Raoufmoghaddam, Saeed; Rood, Marcus T M; Buijze, Florine K W; Drent, Eite; Bouwman, Elisabeth

    2014-07-01

    The conversion of γ-valerolactone (GVL) in three atom-efficient steps to the important polymer precursor ε-caprolactam is reported. The bio-based GVL can be converted to a mixture of isomeric methyl pentenoates (MP) via trans-esterification with methanol with 94% yield (ratio of 3-MP/4-MP=3:1); subsequent aminolysis with ammonia leads to a mixture of pentenamides (PA) almost quantitatively (99% conversion). The resulting pentenamides are ultimately converted into ε-caprolactam via a rhodium-catalyzed intramolecular hydroamidomethylation reaction, comprising an initial hydroformylation of the alkene moiety of PA and subsequent ring-closing reductive amidation of the resulting aldehyde with the amide functionality. A promising yield of caprolactam of about 90% can be obtained with a Rh/xantphos catalyst system in a two-stage hydroformylation-reductive amidation using pure 4-PA as feedstock. The use of 3-PA as a substrate not only results in a significantly lower regioselectivity for the 7-membered lactam, but also in the formation of high amounts of valeramide (VA). Consequently, a best overall yield of caprolactam of nearly 40% could be demonstrated with a Rh/POP-xantphos [POP-xantphos=4,5-bis(2,8-dimethyl-10-phenoxaphosphino)-9,9,-dimethylxanthene] catalyst system based on the 3:1 mixture of 3-PA/4-PA directly obtainable from GVL. PMID:24938779

  17. 40 CFR 63.60 - Deletion of caprolactam from the list of hazardous air pollutants.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Deletion of caprolactam from the list of hazardous air pollutants. 63.60 Section 63.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS...

  18. 40 CFR 63.60 - Deletion of caprolactam from the list of hazardous air pollutants.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Deletion of caprolactam from the list of hazardous air pollutants. 63.60 Section 63.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS...

  19. 40 CFR 63.60 - Deletion of caprolactam from the list of hazardous air pollutants.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Deletion of caprolactam from the list of hazardous air pollutants. 63.60 Section 63.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS...

  20. 40 CFR 63.60 - Deletion of caprolactam from the list of hazardous air pollutants.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Deletion of caprolactam from the list of hazardous air pollutants. 63.60 Section 63.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS...

  1. Thermoresponsive poly(N-vinyl caprolactam)-coated gold nanoparticles: sharp reversible response and easy tunability.

    PubMed

    Beija, Mariana; Marty, Jean-Daniel; Destarac, Mathias

    2011-03-14

    Narrowly distributed poly(N-vinyl caprolactam) obtained by the MADIX/RAFT process was used for the preparation of novel thermoresponsive gold nanoparticles presenting a sharp reversible response to temperature, which can be easily modulated near the physiological temperature by simply changing the polymer molecular weight or concentration. PMID:21240412

  2. Draft Genome Sequence of Caprolactam-Degrading Pseudomonas putida Strain SJ3.

    PubMed

    Hong, Sung-Jun; Park, Gun-Seok; Khan, Abdur Rahim; Jung, Byung Kown; Park, Yeong-Jun; Yoo, Na-Kyung; Lee, Changhee; Park, Choi Kyu; Shin, Jae-Ho

    2015-01-01

    Pseudomonas putida strain SJ3, which possesses caprolactam-degrading ability, was isolated from dyeing industry wastewater in Daegu, Republic of Korea. Here, we describe the draft genome sequence and annotation of the strain. The 5,596,765-bp-long genome contains 4,293 protein-coding genes and 68 RNA genes with 61.70% G+C content. PMID:26205864

  3. Isolation of the epsilon-caprolactam denitrifying bacteria from a wastewater treatment system manufactured with acrylonitrile-butadiene-styrene resin.

    PubMed

    Wang, Chun-Chin; Lee, Chi-Mei

    2007-06-25

    epsilon-Caprolactam has high COD and toxicity, so its discharge to natural water and soil systems may lead to an adverse environmental effect on water quality, endangering public health and welfare. This investigation attempts to isolate epsilon-caprolactam denitrifying bacteria from a wastewater treatment system manufactured with acrylonitrile-butadiene-styrene (ABS) resin. The goal is to elucidate the effectiveness of isolated pure strain and ABS mixed strains in treating epsilon-caprolactam from synthetic wastewater. The results reveal that Paracoccus versutus MDC-3 was isolated from the wastewater treatment system manufactured with ABS resin. The ABS mixed strains and P. versutus MDC-3 can consume up to 1539mg/l epsilon-caprolactam to denitrify from synthetic wastewater. Complete epsilon-caprolactam removal depended on the supply of sufficient electron acceptors (nitrate). Strain P. versutus MDC-3, Hyphomicrobium sp. HM, Methylosinus pucelana and Magnetospirillum sp. CC-26 are related closely, according to the phylogenetic analyses of 16S rDNA sequences. PMID:17161908

  4. In Silico Identification for α-Amino-ε-Caprolactam Racemases by Using Information on the Structure and Function Relationship.

    PubMed

    Payoungkiattikun, Wisarut; Okazaki, Seiji; Nakano, Shogo; Ina, Atsutoshi; H-Kittikun, Aran; Asano, Yasuhisa

    2015-07-01

    In silico identification for enzymes having desired functions is attractive because there is a possibility that numerous desirable enzymes have been deposited in databases. In this study, α-amino-ε-caprolactam (ACL) racemases were searched from the NCBI protein database. Four hundred thirteen fold-type I pyridoxal 5'-phosphate-dependent enzymes which are considered to contain sequences of ACL racemase were firstly obtained by submitting the sequence of ACL racemase from Achromobacter obae to the database. By identifying Lys241 as a key amino acid residue, 13 candidates for ACL racemase were selected. Then, putative ACL racemase genes were synthesized as codon-optimized sequences for expression in Escherichia coli. They were subcloned and expressed in E. coli BL21 and underwent His-tag purification. ACL and amino acid amide racemizing activities were detected among ten of the candidates. The locus tags Oant_4493, Smed_5339, and CSE45_2055 derived from Ochrobactrum anthropi ATCC49188, Sinorhizobium medicae WSM 419, and Citreicella sp. SE45, respectively, showed higher racemization activity against D- and L-ACLs rather than that of ACL racemase from A. obae. Our results demonstrate that the newly discovered ACL racemases were unique from ACL racemase from A. obae and might be useful for applications in dynamic kinetic resolution for D- or L-amino acid production. PMID:26206345

  5. Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

    PubMed Central

    Burkhart, Alexander

    2014-01-01

    Summary The monomer 2-methacrylamido-caprolactam (4) was synthesized from methacryloyl chloride (3) and racemic α-amino-ε-caprolactam (2). Copolymerization of 4 with N,N-dimethylacrylamide (5) was carried out by a free-radical mechanism using 2,2’-azobis(2-methylpropionitrile) (AIBN) as an initiator. The new copolymers show a lower critical solution temperature (LCST) in water and an upper critical solution temperature (UCST) in ethanol, 1-propanol, and 1-butanol. The solubility properties of the copolymers can be influenced significantly by the addition of randomly methylated β-cyclodextrin (CD). The complexation of the copolymers with CD, was confirmed by the use of ROESY-NMR-spectroscopy. PMID:25246954

  6. ε-Caprolactam Utilization by Proteus sp. and Bordetella sp. Isolated From Solid Waste Dumpsites in Lagos State, Nigeria, First Report.

    PubMed

    Sanuth, Hassan Adeyemi; Yadav, Amit; Fagade, Obasola Ezekiel; Shouche, Yogesh

    2013-06-01

    The ε-caprolactam is the monomer of the synthetic non-degradable nylon-6 and often found as nonreactive component of nylon-6 manufacturing waste effluent. Environmental consequences of its toxicity to natural habitats and humans pose a global public concern. Soil samples were collected from three designated solid waste dumpsites, namely, Abule-Egba, Olusosun and Isheri-Igando in Lagos State, Nigeria. Sixteen bacteria isolated from these samples were found to utilize the ε-caprolactam as a sole source of carbon and nitrogen at concentration of ≤20 g l(-1). The isolates were characterized using their 16S rRNA gene sequence and showed similarity with Pseudomonas sp., Proteus sp., Providencia sp., Corynebacterium sp., Lysinibacillus sp., Leucobacter sp., Alcaligenes sp. and Bordetella sp. Their optimal growth conditions were found to be at temperature range of 30 to 35 °C and pH range of 7.0-7.5. High Performance liquid chromatography analysis of the ε-caprolactam from supernatant of growth medium revealed that these isolates have potential to remove 31.6-95.7 % of ε-caprolactam. To the best of our knowledge, this study is first to report the ability of Proteus sp. and Bordetella sp. for ε-caprolactam utilization. PMID:24426112

  7. Poly(N-vinyl caprolactam) grown on nanographene oxide as an effective nanocargo for drug delivery.

    PubMed

    Kavitha, Thangavelu; Kang, Inn-Kyu; Park, Soo-Young

    2014-03-01

    This study evaluated graphene oxide functionalized covalently with poly N-vinyl caprolactam (GO-PVCL) via in situ atomic transfer radical polymerization (ATRP), as a nano-cargo carrier for the efficient delivery of drugs into cells. Water-soluble GO-PVCL exhibited excellent stability in physiological solutions. An anti-cancer drug, camptothecin (CPT), was then loaded onto GO-PVCL with a high payload (20%) through π-π stacking and hydrophobic interactions, and its release could be controlled by varying the pH. PVCL grafted onto GO offers an additional advantage of targeted delivery according to temperature. GO-PVCL showed no obvious toxicity, whereas the CPT-loaded GO-PVCL showed high potency in killing cancer cells in vitro. The drug transportation mechanism was found to be energy-dependent endocytosis. Overall, this study revealed GO-PVCL to be a promising drug delivery vector with high biocompatibility, solubility and stability in physiological solutions, and good payload capacity owing to its small size, low cost, large specific area, ready scalability, and useful non-covalent interactions. This material is expected to be a novel material propitious for biomedical applications. PMID:24316754

  8. Gas phase acetaldehyde production in a continuous bioreactor

    SciTech Connect

    Hwang, Soon Ook . Dept. of Chemical Engineering); Trantolo, D.J. . Center for Biotechnology Engineering); Wise, D.L. . Dept. of Chemical Engineering Northeastern Univ., Boston, MA . Center for Biotechnology Engineering)

    1993-08-20

    The gas phase continuous production of acetaldehyde was studied with particular emphasis on the development of biocatalyst (alcohol oxidase on solid phase support materials) for a fixed bed reactor. Based on the experimental results in a batch bioreactor, the biocatalysts were prepared by immobilization of alcohol oxidase on Amberlite IRA-400, packed into a column, and the continuous acetaldehyde production in the gas phase by alcohol oxidase was performed. The effects of the reaction temperature, flow rates of gaseous stream, and ethanol vapor concentration on the performance of the continuous bioreactor were investigated.

  9. Investigation of HNO2 Production in Solvent Extraction Organic Phases

    SciTech Connect

    Leigh R. Martin

    2014-09-01

    This document is a letter report that was prepared to meet FCR&D level 4 milestone M4FT-14IN0304054, “Investigate HNO2 production in solvent extraction organic phases.” This work was carried out under the auspices of the Fundamental Radiation Chemistry FCR&D work package. This document reports on an initial tests performed to follow HNO2 formation in reference flowsheet relevant organic phases.

  10. Phase modifiers promote efficient production of hydroxymethylfurfural from fructose.

    PubMed

    Román-Leshkov, Yuriy; Chheda, Juben N; Dumesic, James A

    2006-06-30

    Furan derivatives obtained from renewable biomass resources have the potential to serve as substitutes for the petroleum-based building blocks that are currently used in the production of plastics and fine chemicals. We developed a process for the selective dehydration of fructose to 5-hydroxymethylfurfural (HMF) that operates at high fructose concentrations (10 to 50 weight %), achieves high yields (80% HMF selectivity at 90% fructose conversion), and delivers HMF in a separation-friendly solvent. In a two-phase reactor system, fructose is dehydrated in the aqueous phase with the use of an acid catalyst (hydrochloric acid or an acidic ion-exchange resin) with dimethylsulfoxide and/or poly(1-vinyl-2-pyrrolidinone) added to suppress undesired side reactions. The HMF product is continuously extracted into an organic phase (methylisobutylketone) modified with 2-butanol to enhance partitioning from the reactive aqueous solution. PMID:16809536

  11. Employment, Production and Consumption model: Patterns of phase transitions

    NASA Astrophysics Data System (ADS)

    Lavička, H.; Lin, L.; Novotný, J.

    2010-04-01

    We have simulated the model of Employment, Production and Consumption (EPC) using Monte Carlo. The EPC model is an agent based model that mimics very basic rules of industrial economy. From the perspective of physics, the nature of the interactions in the EPC model represents multi-agent interactions where the relations among agents follow the key laws for circulation of capital and money. Monte Carlo simulations of the stochastic model reveal phase transition in the model economy. The two phases are the phase with full unemployment and the phase with nearly full employment. The economy switches between these two states suddenly as a reaction to a slight variation in the exogenous parameter, thus the system exhibits strong non-linear behavior as a response to the change of the exogenous parameters.

  12. Multi Drug Loaded Thermo-Responsive Fibrinogen-graft-Poly(N-vinyl Caprolactam) Nanogels for Breast Cancer Drug Delivery.

    PubMed

    Rejinold, N Sanoj; Baby, Thejus; Chennazhi, K P; Jayakumar, R

    2015-03-01

    This study aims at the targeted delivery of 5-fluorouracil (5-FU) and Megestrol acetate (Meg) loaded fibrinogen-graft-poly(N-Vinyl caprolactam) nanogels (5-FU/Meg-fib-graft-PNVCL NGs) toward α5β1-integrins receptors expressed on breast cancer cells to have enhanced anti-cancer effect in vitro. To achieve this aim, we developed biocompatible thermoresponsive fib-graft-PNVCL NGs using fibrinogen and carboxyl terminated PNVCL via EDC/NHS amidation reaction. The Lower Critical Solution Temperature (LCST) of fib-graft-PNVCL could be tuned according to PNVCL/fibrinogen compositions. The 100-120 nm sized nanogels of fib-graft-PNVCL (LCST = 35 ?1 'C) was prepared using CaCl2 cross-linker. The 5-FU/Meg-fib-graft-PNVCL NGs showed a particle size of 150-170 nm size. The drug loading efficiency with 5-FU was 62% while Meg showed 74%. The 5-FU and Meg release was prominent above LCST than below LCST. The multi drug loaded fib-graft-PNVCL NGs showed enhanced toxicity, apoptosis and uptake by breast cancer (MCF-7) cells compared to their individual doses above their LCST. The in vivo assessment in Swiss albino mice showed sustained release of Meg and 5-FU as early as 3 days, confirming the therapeutic efficiency of the formulation. These results demonstrate an enhanced platform for the future animal studies on breast tumor xenograft model. PMID:26307823

  13. Leaching of Phase II Mercury Control Technology By-Products

    SciTech Connect

    Hesbach, P.A.; Kachur, E.K.

    2007-07-01

    The U.S. EPA has issued a final regulation for control of mercury from coal-fired power plants. An NETL research, development and demonstration program under DOE/Fossil Energy Innovations for Existing Plants is directed toward the improvement of the performance and economics of mercury control from coal-fired plants. The current Phase II of the RD&D program emphasizes the evaluation of performance and cost of control technologies through slip-stream and full scale field testing while continuing the development of novel concepts. One of the concerns of the NETL program is the fate of the captured flue gas mercury which is transferred to the condensed phase by-product stream. These adulterated by-products, both ashes and FGD material, represent the greatest challenge to the DOE goal of increased utilization of by-products. The degree of stability of capture by-products and their potential for release of mercury can have a large economic impact on material sales or the approach to disposal. One of the considerations for mercury control technology is the potential trade-off between effective but temporary mercury capture and less effective but more permanent sequestration. As part of a greater characterization effort of Phase II facility baseline and control technology sample pairs, NETL in-house laboratories have performed aqueous leaching procedures on a select subset of the available sample pairs. This report describes batch leaching results for mercury, arsenic, and selenium.

  14. Oligomeric epoxide–amine adducts based on 2-amino-N-isopropylacetamide and α-amino-ε-caprolactam: Solubility in presence of cyclodextrin and curing properties

    PubMed Central

    Fischer, Julian

    2013-01-01

    Summary 2-Amino-N-isopropylacetamide and α-amino-ε-caprolactam were reacted with glycerol diglycidyl ether to give novel oligomeric thermoresponsive epoxide–amine adducts. These oligomers exhibit a lower critical solution temperature (LCST) behavior in water. The solubility properties were influenced with randomly methylated β-cyclodextrin (RAMEB-CD) and the curing properties of the amine–epoxide mixtures were analyzed by oscillatory rheology and differential scanning calorimetry, whereby significant differences in setting time, viscosity, and stiffness were observed. PMID:24367444

  15. Treatment of glycerol phase formed by biodiesel production.

    PubMed

    Hájek, Martin; Skopal, Frantisek

    2010-05-01

    Glycerol is a by-product of biodiesel produced by transesterification and is contained in the glycerol phase together with many other materials such as soaps, remaining catalyst, water, and esters formed during the process. The content of glycerol is approximately 30-60 wt.%. In this paper, treatments of the glycerol phase to obtain glycerol with a purity of 86 wt.% (without distillation) and a mixture of fatty acids with esters (1:1) or only a mixture of fatty acids with a purity of 99 wt.% are presented. The treatment was carried out by removing of alkaline substances and esters. Fatty acids were produced by saponification of the remaining esters and subsequent neutralization of alkaline substances by phosphoric, sulfuric, hydrochloric, or acetic acids. Salts are by-products and, in the case of phosphoric acid can be used as potash-phosphate fertilizer. The process of treatment is easy and environmentally friendly, because no special chemicals or equipment are required and all products are utilizable. PMID:20074939

  16. Is phase-shift mask technology production-worthy?

    NASA Astrophysics Data System (ADS)

    Chen, Mung

    1991-07-01

    The feasibility and potential of Phase-Shift Mask (PSM) for sub- 0.5 urn fabrication have been clearly demonstrated. In the '91 SPIE Microlithography Syrnposium, a total of 18 papers on PSM were presented. Many new, innovative designs have been proposed. However, there is still a myriad of technical and logistic problems, which must be resolved for production implementation. We organized the workshop and panel discussion in the hope that the participants would collectively make an assessment of the maturity of the technology and reach a common understanding of the key issues.

  17. Freeze concentration of dairy products: Phase 2. Final report

    SciTech Connect

    Best, D.E.; Vasavada, K.C.; Woolf, H.

    1995-10-01

    Conventional dairy industry evaporators convert an estimated 60 billion pounds of milk and whey products annually into dairy powders. However, many evaporators currently used by dairy processors are old and inefficient and damage the dairy powders through heat abuse. This results in lost organoleptic and functional qualities in the finished dairy products. EPRI report EM-5232 indicated that substitution of freeze concentration for evaporation and distillation in all feasible industry applications could save customers $5.5 billion annually, while increasing electric power consumption by 20 billion kWt/yr. EPRI CU-6292 reported on Phase I work, concluding that freeze concentration of dairy products was technically feasible based on pilot plant studies. The semicommercial-scale Process development units was successfully installed and brought up to 3-A processing standards. This unit achieved continuous runs of up to 510 hours. An expert safety panel affirmed the generally recognized as safe (GRAS) status of freeze-concentrated milk ingredients, which were used in formulating ice cream, cream cheese, milk chocolate, and other products for consumer evaluation. Consumer evaluations documented that the functional and organoleptic properties of reconstituted freeze-concentrated skim milk are equal or superior to those of fresh skim milk, skim milk concentrates, or nonfat dry milk powders.

  18. Economical Production of Pu-238: NIAC Phase I Final Report

    NASA Technical Reports Server (NTRS)

    Howe, Steven D.; Crawford, Douglas; Navarro, Jorge; O'Brien, Robert C.; Katalenich, Jeff; Ring, Terry

    2016-01-01

    All space exploration missions traveling beyond Jupiter must use radioisotopic power sources for electrical power. The best isotope to power these sources is plutonium-238 (Pu-238). The US supply of Pu-238 is almost exhausted and will be gone within the next decade. The Department of Energy has initiated a production program with a $10M allocation from NASA but the cost is estimated at over $100M to get to production levels. The Center for Space Nuclear Research (CSNR) has conceived of a potentially better process to produce Pu-238 earlier and for significantly less cost. Potentially, the front end capital costs could be provided by private industry such that the government only had to pay for the product produced. In the Phase I NIAC (NASA Innovative Advanced Concepts) grant, the CSNR has evaluated the feasibility of using a low power, commercially available nuclear reactor to produce 1.5 kg of Pu-238 per year. The impact on the neutronics of the reactor have been assessed, the amount of Neptunium target material estimated, and the production rates calculated. In addition, the size of the post-irradiation processing facility has been established. Finally, as the study progressed, a new method for fabricating the Pu-238 product into the form used for power sources has been identified to reduce the cost of the final product. In short, the concept appears to be viable, can produce the amount of Pu-238 needed to support the NASA missions, can be available within a few years, and will cost significantly less than the current DOE program.

  19. Binding and release of drugs into and from thermosensitive poly(N-vinyl caprolactam) nanoparticles.

    PubMed

    Vihola, Henna; Laukkanen, Antti; Hirvonen, Jouni; Tenhu, Heikki

    2002-07-01

    Three model drug substances, the beta-blocking agents nadolol and propranolol and a choline-esterase inhibitor tacrine, were used in order to determine how different drug molecules affect the behavior of thermally responsive polymer nanoparticles composed of poly(N-vinylcaprolactam) (PVCL). Pure PVCL particles in water exist in a swollen state at room temperature, but the size of the particles decreases discontinuously when the temperature is raised above the volume phase transition temperature. At temperatures above this transition temperature, water is expelled out from the nanoscopic hydrogel particles. Light scattering studies revealed that the more hydrophobic drug substances, propranolol and tacrine, considerably swell the PVCL-microgel. The more hydrophilic drug, nadolol, decreased the transition temperature of PVCL particles, whereas the transition temperature values of pure PVCL particles and that of the added propranolol and tacrine were quite similar. Attenuated drug release results showed that the beta-blocking agents were tightly bound to the microgel, and this was more evident at higher temperatures. On the contrary, the release of tacrine across the cellulose membrane was increased when PVCL particles were present. Thus, both physical and chemical properties of the drugs clearly affected their binding to PVCL particles and the release of drugs was affected by the temperature. PMID:12113893

  20. Off-equilibrium photon production during the chiral phase transition

    SciTech Connect

    Michler, Frank; Hees, Hendrik van; Dietrich, Dennis D.; Leupold, Stefan; Greiner, Carsten

    2013-09-15

    In the early stage of ultrarelativistic heavy-ion collisions chiral symmetry is restored temporarily. During this so-called chiral phase transition, the quark masses change from their constituent to their bare values. This mass shift leads to the spontaneous non-perturbative creation of quark–antiquark pairs, which effectively contributes to the formation of the quark–gluon plasma. We investigate the photon production induced by this creation process. We provide an approach that eliminates possible unphysical contributions from the vacuum polarization and renders the resulting photon spectra integrable in the ultraviolet domain. The off-equilibrium photon numbers are of quadratic order in the perturbative coupling constants while a thermal production is only of quartic order. Quantitatively, we find, however, that for the most physical mass-shift scenarios and for photon momenta larger than 1 GeV the off-equilibrium processes contribute less photons than the thermal processes. -- Highlights: •We investigate first-order photon emission arising from the chiral mass shift. •We provide an ansatz eliminating possible unphysical vacuum contributions. •Our ansatz leads to photon spectra being integrable in the ultraviolet domain.

  1. Pupils' Readiness for Self-Regulated Learning in the Forethought Phase of Exploratory Production

    ERIC Educational Resources Information Center

    Metsärinne, Mika; Kallio, Manne; Virta, Kalle

    2015-01-01

    This article discusses pupils' readiness for self-regulation in Exploratory Production in Technology Education. In the forethought phase of Exploratory Production, pupils envision and regulate their technological production activities. Next, in the performance phase, the envisioned goals are tried and implemented through ideating, planning…

  2. Freeze concentration of dairy products Phase 2. Final report

    SciTech Connect

    Best, D.E.; Vasavada, K.C.

    1993-09-01

    An efficient, electrically driven freeze concentration system offers potential for substantially increasing electricity demand while providing the mature dairy industry with new products for domestic and export markets together with enhanced production efficiencies. Consumer tests indicate that dairy products manufactured from freeze-concentrated ingredients are either preferred or considered equivalent in quality to fresh milk-based products. Economic analyses indicate that this technology should be competitive with thermal evaporation processes on a commercial basis.

  3. Estimating production and consumption of solid reactive Fe phases in marine sediments from concentration profiles

    EPA Science Inventory

    1D diffusion models may be used to estimate rates of production and consumption of dissolved metabolites in marine sediments, but are applied less often to the solid phase. Here we used a numerical inverse method to estimate solid phase Fe(III) and Fe(II) consumption and product...

  4. Power production with two-phase expansion through vapor dome

    SciTech Connect

    Amend, W.E.; Toner, S.J.

    1984-08-07

    In a system wherein a fluid exhibits a regressive vapor dome in a T-S diagram, the following are provided: a two-phase nozzle receiving the fluid in pressurized and heated liquid state and expanding the received liquid into saturated or superheated vapor state, and apparatus receiving the saturated or superheated vapor to convert the kinetic energy thereof into power.

  5. Entropy production in the early-cosmology pionic phase

    NASA Astrophysics Data System (ADS)

    Dobado, Antonio; Llanes-Estrada, Felipe J.; Rodríguez Fernández, David

    2016-07-01

    We point out that in the early universe, for temperatures in the approximate interval 150-80 MeV (after the quark-gluon plasma), pions carried a large share of the entropy and supported the largest inhomogeneities. Its thermal conductivity (previously calculated) allows the characterization of entropy production due to equilibration (damping) of thermal fluctuations. Simple model distributions of thermal fluctuations are considered and the associated entropy production evaluated.

  6. Aqueous-Phase Photochemical Production of Oxidants in Atmospheric Waters.

    NASA Astrophysics Data System (ADS)

    Allen, John Morrison

    1992-01-01

    The photochemical formation and subsequent reactions of oxidants plays an important role in the overall chemistry of the atmosphere. Much of the interest in atmospheric oxidation reactions has been fueled by the environmental consequences of the oxidation of sulfur dioxide (SO _2) forming sulfuric acid (H_2 SO_4). Oxidation reactions also play a crucial role in other atmospheric chemical transformations such as: (1) the destruction of tropospheric ozone, (2) redox cycling of transition metals, and (3) oxidation of organic compounds. Much of the research pertaining to atmospheric oxidant formation and the reactions that these oxidants undergo has centered upon gas-phase photochemical oxidant formation and: (1) subsequent reactions in the gas phase, or (2) partitioning of oxidants into cloud and fog drops and subsequent reactions in the aqueous phase. Only a very limited amount of data is available concerning aqueous -phase photochemical sources of oxidants in cloud and fog drops. The focus of one aspect of the work presented in this dissertation is upon the aqueous-phase sunlight photochemical formation of oxidants in authentic cloud and fog water samples from across the United States and Canada. It will be demonstrated that atmospheric waters typically absorb solar ultraviolet radiation at wavelengths ranging from 290 to 340 nm. This absorption is due to the presence of chemical constituents in the cloud and fog waters that contain chromophoric functional groups that give rise to the formation of: (1) singlet molecular oxygen O_2(^1Delta_ {rm g}), (2) peroxyl radicals (HO _2cdot and RO_2 cdot), (3) peroxides (HOOH, ROOH, and ROOR '), and (4) hydroxyl radical ( cdotOH). This work will demonstrate that aqueous-phase photochemical reactions are a significant and in some cases dominant source of these oxidants in cloud and fog drops. The transition metal catalyzed oxidation of SO _2 to H_2SO _4 by molecular oxygen has been extensively studied. This reaction is thought

  7. Production of distributed phase plates using an energetic ion process

    NASA Astrophysics Data System (ADS)

    Smith, Douglas J.; Warner, Joy A.; LeBarron, Nelson E.; LaDelia, Salvatore

    1999-04-01

    Laser-driven implosion experiments require optical phase conversion to create a uniformly irradiated target. Distributed phase plates provide a quasi-random phase front that aids in beam smoothing on the target; however, the DPP must survive the high fluences of the tripled OMEGA beam at 351 nm. The continuous DPP produces higher efficiency and less risk of damage to opposing optics than the previous binary design. DPPs are created by exposing a gray scale pattern in photoresist and then etching the pattern in to silica. Several problems were solved during the development stage of ion etching DPPs. The etch uniformity was limited to less than 6 percent across a 28-cm clear aperture by modeling the 16-cm ion source and erosion characteristics of the photoresist and silica. Surface texturing was linked to overheating of the photoresist by the ion source and was solved by radiant cooling. Near-field defects capable of focusing damage in levels of fluence on downstream optics were created in the photoresist exposure process and were removed after etching. The damage thresholds of the silica surface generally increase after etching is fare is taken to avoid re-sputtering of tooling onto the optics surface. Sixty ion-etched DPPs were installed in December 1997 and, currently, damage has not been observed on the optics.

  8. Phase compositions of the products from electrical explosion of zirconium-carbon mixtures

    SciTech Connect

    Pavlov, I.E.

    1987-12-01

    We present new information on the phase compositions of the products produced by electrical explosion in water from powder mixtures of zirconium and graphite. The x-ray patterns were recorded with Cu K/sub ..cap alpha../ radiation with a DRON-2.0 diffractometer. The products contain mainly cubic phase (NaCl type) and ZrO/sub 2/ (monoclinic and cubic forms). The unit-cell parameter for the cubic phase (NaCl type) increased with the carbon concentration in the initial mixture. The amount of ZrC/sub x/O/sub y/ in the products increases with the carbon content in the mixture.

  9. Complexation between poly(maleic acid/octyl vinyl ether) and poly(vinyl caprolactam) in aqueous solution and at the alumina/water interface.

    PubMed

    Qiu, Q; Somasundaran, P

    2002-09-01

    Solution and interfacial properties of binary polymer mixtures of poly(maleic acid/octyl vinyl ether) (PMAOVE) and poly(vinyl caprolactam) (PVCAP) have been studied for the alumina/water system. To test the hydrophobic effect, mixtures of poly(maleic acid/methyl vinyl ether) (PMAMVE) and PVCAP are also investigated and compared to the behavior of PMAOVE/PVCAP. At low pH, both polymer mixtures become turbid upon mixing. The turbidity increases at low mixing ratios of PVCAP to the vinyl ether component, reaches a maximum, and then decreases at higher mixing ratios. Upon shifting the pH to the alkaline range, i.e., pH 7.5 and above, the turbid solution becomes clear for both the polymer mixtures. Cloud point measurements indicate the absence of complexation of PVCAP with PMAMVE under the alkaline conditions, but strong interaction with PMAOVE. This is attributed to the different forces involved in the complexation among the polymers: H bonding for PVCAP/PMAMVE and both H bonding and hydrophobic effects for PVCAP/PMAOVE. At the alumina/water interface, the normally nonadsorbing PVCAP is triggered to adsorb by PMAOVE, attributed to the hydrophobic complexation between the two. However, the adsorption of PVCAP shows a maximum as a function of the concentration of PMAOVE. At concentrations of PMAOVE above the onset of its own plateau adsorption, the amount of PVCAP triggered to adsorb is reduced possibly due to the polymer complex formation in solution. PMID:16290852

  10. Freeze concentration of dairy products, Phase 1: Final report

    SciTech Connect

    Luksas, A.; Ahmed, S.; Johnson, T.A.

    1989-03-01

    The objective of this study was to explore freeze concentration as a process to replace thermal evaporation in the dairy industry. The goals of the study were to save energy by converting concentration processes to an efficient, electrically powered, refrigeration system, and to create higher quality and innovative products that might bring new life to a nature dairy market. A small freeze concentration pilot plant was used to concentrate products for quality comparisons, for physical and chemical analytical determinations, and to discover any equipment/product attributes or limitations. Data was correlated to compare operating economics of freeze concentrations superior to the fresh feedstock in sensory and functionality tests upon reconstitution. Laboratory testing showed equal or superior quality in resulting spray dried powders from freeze concentrates. Freeze concentration was shown to be economically competitive with thermal processes and second generation freezing technology is projected to produce a substantially less expensive product and offer other advantages over current thermally produced goods. 31 figs., 14 tabs.

  11. Thematic Mapper Image Production in the Engineering Checkout Phase

    NASA Technical Reports Server (NTRS)

    Fischel, D.; Lyon, J. C.

    1984-01-01

    Thematic Mapper data processing during LANDSAT 4's first year was performed on an engineering evaluation basis. Fully corrected products were created for some 282 scenes during this period using software and systems based upon the intended full production systems to become operational following the evaluation period. The engineering systems included substantial software and procedures for assessing spacecraft, instrument and ground processing algorithmic behavior. The data systems are described in terms of performance objectives, processing organization and data flow, quality assurance measurements and achievement of goals. The a priori implementation of TM radiometric and geometric corrections is described. Changes to processing suggested by or implemented on the basis of on-orbit data analysis are discussed. Spacecraft, instrument and algorithmic performance are evaluated.

  12. Ensuring crustacean product quality in the post-harvest phase.

    PubMed

    Neil, Douglas M

    2012-06-01

    Recent studies of the fisheries for the Norway lobster, Nephrops norvegicus (L.), have illustrated the negative effects of pathogens and of the physiological stresses of capture processes on the exploitation of live animals and their products, and have identified mitigating measures. Firstly, having established that trawl capture of N. norvegicus is highly stressful, but that these animals have powerful physiological mechanisms of recovery, procedures for on-board recovery of animals destined for vivier transport to distant European markets have been implemented commercially, with significant improvements in survival rates. Such procedures also mitigate against the initiation of a stress-induced muscle necrosis. Secondly, measurements of post-mortem autolytic and spoilage processes have identified the existence of a post-capture 'handling window' of several hours which allows the whole or tailed products to be preserved, by icing or freezing, without detriment to quality. Commercial consortia of Scottish fishermen are exploiting this opportunity to extend product shelf-life by freezing at sea within this handling window. Thirdly, the well-documented infections of Scottish N. norvegicus populations by the dinoflagellate Hematodinium sp. not only provide examples of pathogen-induced mortality, but also have effects on post-harvest products including vivier transport losses and changes in post-mortem degradation leading to earlier organoleptic rejection. Under commercial conditions these effects can be mitigated by post-capture visual screening, but only during the periods of peak patent infection when parasitised animals are visually identifiable. Wider implementation of such mitigating procedures during the harvesting of wild-caught crustaceans will contribute to a more sustainable exploitation of these valuable marine resources. PMID:22433999

  13. Polysaccharide production by microalgae. Final report on phase 1

    SciTech Connect

    Benemann, J.R.; Weissman, J.C.

    1980-04-01

    The feasibility of producing commercially valuable polysaccharides from microalgal biomass was demonstrated. Algal biomass with a high polysaccharide content was produced by subjecting cultures to short periods of nitrogen limitation without decreasing overall biomass production rates. Three different algae were studied--unicellular blue-green alga Synechococcus leopoliensis, filamentous blue-green alga Spirulina platensis, and a green colonial alga, Scenedesmus sp. Batch cultures were grown with varying amounts of nitrate to limit nitrogen uptake at various stages in the batch growth curve. In the presence of high nitrate concentrations, the Synechococcus culture became stationary within four days, whereas both Spirulina and Scenedesmus maintained an appreciable growth rate and high daily productivities, for at least a week. With limiting nitrate concentrations, the cellular content of polysaccharide (measured as total carbohydrates) increased markedly, from 20-25 percent to 70-80 percent in Synechococcus and Spirulina. Depending on the level of nitrate used, onset of nitrogen limitation could be set at various culture densities. In all cases, little or no inhibition of total biomass production was noted.

  14. Production of Coherent Phase Space Islands in Trapped Plasma

    NASA Astrophysics Data System (ADS)

    Hunter, Eric; Povilus, Alex; Belmore, Nathan; Lewis, Nicole; Shanman, Sabrina; Fajans, Joel

    2015-11-01

    Particles are coherently extracted from a cold Maxwellian distribution into phase space islands by applying a fixed-frequency RF drive while the plasma bounce frequency is swept downward by lowering the potential confining the plasma. These objects can appear spontaneously in pure electron and mixed ion plasma experiments during particle extraction when the noise power spectrum of the confining potential has peaks in the rf band, as is often the case in a laboratory environment. Interestingly, the particles in these islands have been observed to form tight energy distributions, making the mechanism potentially useful for low energy/monoenergetic plasma injection devices. In particular, these features would be useful for antimatter spectroscopy and mixing for antihydrogen formation. This work is supported by DoE, Grant DE-FG02-06ER54904.

  15. Irreversible entropy production in two-phase flows with evaporating drops

    NASA Technical Reports Server (NTRS)

    Bellan, J.; Okong'o, N. A.

    2002-01-01

    A derivation of the irreversible entropy production, that is the dissipation, in two-phase flows is presented for the purpose of examining the effect of evaporative-drop modulation of flows having turbulent features.

  16. Magnetic field dependence of the product yields of cycloheptanone photolysis in the dilute gas phase

    NASA Astrophysics Data System (ADS)

    Stich, E. M.; Baumeister, W. F.; Huber, J. Robert

    1984-07-01

    The product yields of the gas-phase photolysis of cycloheptanone were measured in magnetic fields up to 10 kG. The magnetic-field effect is explained in terms of the radical pair model. A reaction mechanism is proposed that explains the magnetic field dependence, pressure dependence, and excitation enegy dependence of the gas-phase photochemistry of cycloheptanone.

  17. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, FRANCE COMPRESSOR PRODUCTS EMISSIONS PACKING, PHASE I REPORT

    EPA Science Inventory

    The report presents results of a Phase I test of emissions packing technology offered by France Compressor Products which is designed to reduce methane leaks from compressor rod packing when a compressor is in a standby and pressurized state. This Phase I test was executed betwee...

  18. 30 CFR 203.33 - To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... produces 18 BCF, and the qualified well on lease B produces 37 BCF, then the production volume from and... 30 Mineral Resources 2 2011-07-01 2011-07-01 false To which production do I apply the RSV earned... To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells on...

  19. Determination of alternative fuels combustion products: Phase 2 final report

    SciTech Connect

    Whitney, K.A.

    1997-06-01

    This report describes the laboratory efforts to accomplish four independent tasks: (1) speciation of hydrocarbon exhaust emissions from a light-duty vehicle operated over the chassis dynamometer portion of the light-duty FTP after modifications for operation on butane and butane blends; (2) evaluation of NREL`s Variable Conductance Vacuum Insulated Catalytic Converter Test Article 4 for the reduction of cold-start FTP exhaust emissions after extended soak periods for a Ford FFV Taurus operating on E85; (3) support of UDRI in an attempt to define correlations between engine-out combustion products identified by SwRI during chassis dynamometer testing, and those found during flow tube reactor experiments conducted by UDRI; and (4) characterization of small-diameter particulate matter from a Ford Taurus FFV operating in a simulated fuel-rich failure mode on CNG, LPG, M85, E85, and reformulated gasoline. 22 refs., 18 figs., 17 tabs.

  20. Homogeneous, single-phase hydroformylation of olefins using ionic phosphines and novel catalyst/product separation

    SciTech Connect

    Abatjoglou, A.G.; Peterson, R.R.; Bryant, D.R.

    1995-12-01

    A high efficiency low pressure hydroformylation process for higher molecular weight olefins has been developed using rhodium/ionic phosphine catalyst. Catalyst solubilization in the non-polar reactants and products is achieved using specialized solubilizing agents, such as N-methyl pyrrolidone (NMP), yielding single-phase systems. Separation of catalyst from product is induced by the addition of small amounts of water outside the hydroformylation reactor. Under the two-phase conditions, most of the catalyst components are found in the polar NMP/water phase, and the products (aldehydes, olefins, reaction byproducts) in a separate, non-polar, phase. The catalyst phase is recycled to the reactors after thorough drying to ensure a single homogeneous phase at reaction conditions. Traces of catalyst and solubilizing agent are effectively recovered from the product and recycled. A major advantage of this process, over water-based two-phase systems, is the high catalytic reactivities and concomitant high olefin efficiencies (>90%) which are achieved with olefins of low, water solubility.

  1. Irreversible Entropy Production in Two-Phase Mixing Layers

    NASA Technical Reports Server (NTRS)

    Okongo, Nora

    2003-01-01

    This report presents a study of dissipation (irreversible production of entropy) in three-dimensional, temporal mixing layers laden with evaporating liquid drops. The purpose of the study is to examine the effects of evaporating drops on the development of turbulent features in flows. Direct numerical simulations were performed to analyze transitional states of three mixing layers: one without drops, and two that included drops at different initial mass loadings. Without drops, the dissipation is essentially due to viscous effects. It was found that in the presence of drops, the largest contribution to dissipation was made by heating and evaporation of the drops, and that at large length scales, this contribution is positive (signifying that the drops reduce turbulence), while at small scales, this contribution is negative (the drops increase turbulence). The second largest contribution to dissipation was found to be associated with the chemical potential, which leads to an increase in turbulence at large scales and a decrease in turbulence at small scales. The next smaller contribution was found to be that of viscosity. The fact that viscosity effects are only third in order of magnitude in the dissipation is in sharp contrast to the situation for the mixing layer without the drops. The next smaller contribution - that of the drag and momentum of the vapor from the drops - was found to be negative at lower mass loading but to become positive at higher mass loading.

  2. Phase 3 process overview and the ESO Science Data Products Standard

    NASA Astrophysics Data System (ADS)

    Mascetti, L.; Arnaboldi, M.; Delmotte, N.; Micol, A.; Retzlaff, J.

    2015-12-01

    The ESO Phase 3 infrastructure provides a channel to submit reduced data products for publication to the astronomical community at large and long-term data preservation in the ESO science archive facility. The ESO archive serves as the central collection point for data reduced by ESO users but also for the products of in-house pipeline data processing. One unique standard data format is associated to each type of product like image, spectrum, IFU cube, etc. Here we present an overview of the Phase 3 process and its key features, the data types supported by the the ESO Science Data Products Standard and the data collections already served by the Phase 3 service.

  3. Understanding the aqueous phase ozonolysis of isoprene: distinct product distribution and mechanism from the gas phase reaction

    NASA Astrophysics Data System (ADS)

    Wang, H. L.; Huang, D.; Zhang, X.; Zhao, Y.; Chen, Z. M.

    2012-08-01

    The aqueous phase reaction of volatile organic compounds (VOCs) has not been considered in most analyses of atmospheric chemical processes. However, some experimental evidence has shown that, compared to the corresponding gas phase reaction, the aqueous chemical processes of VOCs in the bulk solutions and surfaces of ambient wet particles (cloud, fog, and wet aerosols) may potentially contribute to the products and formation of secondary organic aerosol (SOA). In the present study, we performed a laboratory experiment of the aqueous ozonolysis of isoprene at different pHs (3-7) and temperatures (4-25 °C). We detected three important kinds of products, including carbonyl compounds, peroxide compounds, and organic acids. Our results showed that the molar yields of these products were nearly independent of the investigated pHs and temperatures, those were (1) carbonyls: 56.7 ± 3.7 % formaldehyde, 42.8 ± 2.5 % methacrolein (MAC), and 57.7 ± 3.4 % methyl vinyl ketone (MVK); (2) peroxides: 53.4 ± 4.1 % hydrogen peroxide (H2O2) and 15.1 ± 3.1 % hydroxylmethyl hydroperoxide (HMHP); and (3) organic acids: undetectable (<1 % estimated by the detection limit). Based on the amounts of products formed and the isoprene consumed, the total carbon yield was estimated to be 94.8 ± 4.1 %. This implied that most of the products in the reaction system were detected. The combined yields of both MAC + MVK and H2O2 + HMHP in the aqueous isoprene ozonolysis were much higher than those observed in the corresponding gas phase reaction. We suggest that these unexpected high yields of carbonyls and peroxides are related to the greater capability of condensed water, compared to water vapor, to stabilize energy-rich Criegee radicals. This aqueous ozonolysis of isoprene (and possibly other biogenic VOCs) could potentially occur on the surfaces of ambient wet particles and plants. Moreover, the high-yield carbonyl and peroxide products might provide a considerable source of aqueous phase

  4. Development of processes for the production of solar grade silicon from halides and alkali metals, phase 1 and phase 2

    NASA Technical Reports Server (NTRS)

    Dickson, C. R.; Gould, R. K.; Felder, W.

    1981-01-01

    High temperature reactions of silicon halides with alkali metals for the production of solar grade silicon are described. Product separation and collection processes were evaluated, measure heat release parameters for scaling purposes and effects of reactants and/or products on materials of reactor construction were determined, and preliminary engineering and economic analysis of a scaled up process were made. The feasibility of the basic process to make and collect silicon was demonstrated. The jet impaction/separation process was demonstrated to be a purification process. The rate at which gas phase species from silicon particle precursors, the time required for silane decomposition to produce particles, and the competing rate of growth of silicon seed particles injected into a decomposing silane environment were determined. The extent of silane decomposition as a function of residence time, temperature, and pressure was measured by infrared absorption spectroscopy. A simplistic model is presented to explain the growth of silicon in a decomposing silane enviroment.

  5. 30 CFR 203.33 - To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... phase 3 ultra-deep well that earns your lease the RSV begins production (other than test production). (2... well on lease B produces 37 BCF, then the production volume from and allocated to lease A to which the... 30 Mineral Resources 2 2010-07-01 2010-07-01 false To which production do I apply the RSV...

  6. Gas-phase products and secondary aerosol yields from the ozonolysis of ten different terpenes

    NASA Astrophysics Data System (ADS)

    Lee, Anita; Goldstein, Allen H.; Keywood, Melita D.; Gao, Song; Varutbangkul, Varuntida; Bahreini, Roya; Ng, Nga L.; Flagan, Richard C.; Seinfeld, John H.

    2006-04-01

    The ozonolyses of six monoterpenes (α-pinene, β-pinene, 3-carene, terpinolene, α-terpinene, and myrcene), two sesquiterpenes (α-humulene and β-caryophyllene), and two oxygenated terpenes (methyl chavicol and linalool) were conducted individually in Teflon chambers to examine the gas-phase oxidation product and secondary organic aerosol (SOA) yields from these reactions. Particle size distribution and number concentration were monitored and allowed for the calculation of the SOA yield from each experiment, which ranged from 1 to 54%. A proton transfer reaction mass spectrometer (PTR-MS) was used to monitor the evolution of gas-phase products, identified by their mass to charge ratio (m/z). Several gas-phase oxidation products, formaldehyde, acetaldehyde, formic acid, acetone, acetic acid, and nopinone, were identified and calibrated. Aerosol yields, and the yields of these identified and calibrated oxidation products, as well as many higher m/z oxidation products observed with the PTR-MS, varied significantly between the different parent terpene compounds. The sum of measured oxidation products in the gas and particle phase ranged from 33 to 77% of the carbon in the reacted terpenes, suggesting there are still unmeasured products from these reactions. The observations of the higher molecular weight oxidation product ions provide evidence of previously unreported compounds and their temporal evolution in the smog chamber from multistep oxidation processes. Many of the observed ions, including m/z 111 and 113, have also been observed in ambient air above a Ponderosa pine forest canopy, and our results confirm they are consistent with products from terpene + O3 reactions. Many of these products are stable on the timescale of our experiments and can therefore be monitored in field campaigns as evidence for ozone oxidative chemistry.

  7. Importance of granulometry on phase evolution and phase-to-phase relationships of experimentally burned impure limestones intended for production of hydraulic lime and/or natural cement

    NASA Astrophysics Data System (ADS)

    Kozlovcev, Petr; Přikryl, Richard; Přikrylová, Jiřina

    2015-04-01

    In contrast to modern ordinary Portland cement production from finely ground raw material blends, ancient burning of hydraulic lime was conducted by burning larger pieces of natural raw material. Due to natural variability of raw material composition, exploitation of different beds from even one formation can result the product with significantly different composition and/or properties. Prague basin (Neoproterozoic to pre-Variscan Palaeozoic of the central part of the Bohemian Massif - the so-called Barrandian area, Czech Republic) represents a classical example of the limestone-rich region with long-term history of limestone burning for quick lime and/or various types of hydraulic binders. Due to the fact that burning of natural hydraulic lime has been abandoned in this region at the turn of 19th/20th c., significant gap in knowledge on the behavior of various limestone types and on the influence of minor variance in composition on the quality of burned product is encountered. Moreover, the importance of employment of larger pieces of raw material for burning for the development of proper phase-to-phase relationships (i.e. development of hydraulic phases below sintering temperature at mutual contacts of minerals) has not been examined before. To fill this gap, a representative specimens of major limestone types from the Prague basin have been selected for experimental study: Upper Silurian limestone types (Přídolí and Kopanina Lms.), and Lower Devonian limestones (Radotín, Kotýs, Řeporyje, Dvorce-Prokop, and Zlíchov Lms.). Petrographic character of the experimental material was examined by polarizing microscopy, cathodoluminescence, scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS), and X-ray diffraction (XRD) of insoluble residue. Based on the data from wet silicate analyses, modal composition of studied impure limestones was computed. Experimental raw material was burned in laboratory electric furnace at 1000 and 1200°C for 3

  8. Three-phase hollow fiber liquid-phase microextraction of organophosphorous nerve agent degradation products from complex samples.

    PubMed

    Desoubries, Charlotte; Chapuis-Hugon, Florence; Bossée, Anne; Pichon, Valérie

    2012-07-01

    Degradation products of chemical warfare agents are considered as important environmental and biological markers of chemical attacks. Alkyl methylphosphonic acids (AMPAs), resulting from the fast hydrolysis of nerve agents, such as sarin and soman, and the methylphosphonic acid (MPA), final degradation product of AMPAs, were determined from complex matrices by using an emergent and miniaturized extraction technique, the hollow fiber liquid-phase microextraction (HF-LPME), before their analysis by liquid chromatography coupled to mass spectrometry (LC-MS). After studying different conditions of separation in the reversed phase LC-MS analysis, the sample treatment method was set up. The three-phase HF-LPME was carried out by using a porous polypropylene (PP) hollow fiber impregnated with 1-octanol that separates the donor and acceptor aqueous media. Various extraction parameters were evaluated such as the volume of the sample, the effect of the pH and the salt addition to the sample, the pH of the acceptor phase, the extraction temperature, the stirring speed of the sample, the immersion time in the organic solvent and the time of extraction. The optimum conditions were applied to the determination of MPA and five AMPAs in real samples, such as surface waters and urine. Compounds were extracted from a 3 mL acidified sample into only 6 μL of alkaline water without any other pretreatment of the complex matrices. Enrichment factors (EFs) higher than 170 were obtained for three less polar AMPAs. Limits of quantification (LOQs) in the 0.013-5.3 ng mL(-1) range were obtained after microextraction of AMPAs from river water and in the range of 0.056-4.8 ng mL(-1) from urine samples with RSD values between 1 and 9%. PMID:22705170

  9. Bacterial Growth Phase Influences Methylmercury Production by the Sulfate-Reducing Bacterium Desulfovibrio desulfuricans ND132

    SciTech Connect

    Biswas, Abir; Brooks, Scott C; Miller, Carrie L; Mosher, Jennifer J; Yin, Xiangping Lisa; Drake, Meghan M

    2011-01-01

    The effect of bacterial growth phase is an aspect of mercury (Hg) methylation that previous studies have not investigated in detail. Here we consider the effect of growth phase (mid-log, late-log and late stationary phase) on Hg methylation by the known methylator Desulfovibrio desulfuricans ND132. We tested the addition of Hg alone (chloride-complex), Hg with Suwannee River natural organic matter (SRNOM) (unequilibrated), and Hg equilibrated with SRNOM on monomethylmercury (MMHg) production by ND132 over a growth curve in pyruvate-fumarate media. This NOM did not affect MMHg production even under very low Hg:SRNOM ratios, where Hg binding is predicted to be dominated by high energy sites. Adding Hg or Hg-NOM to growing cultures 24h before sampling (late addition) resulted in {approx}2x greater net fraction of Hg methylated than for comparably aged cultures exposed to Hg from the initial culture inoculation (early addition). Mid- and late-log phase cultures produced similar amounts of MMHg, but late stationary phase cultures (both under early and late Hg addition conditions) produced up to {approx}3x more MMHg, indicating the potential importance of growth phase in studies of MMHg production.

  10. Bacterial Growth Phase Influences Methylmercury Production by the Sulfate-Reducing Bacterium Desulfovibrio desulfuricans ND132

    SciTech Connect

    Biswas, Abir; Brooks, Scott C; Miller, Carrie L; Mosher, Jennifer J; Yin, Xiangping Lisa; Drake, Meghan M

    2011-01-01

    The effect of bacterial growth phase is an aspect of mercury (Hg) methylation that previous studies have not investigated in detail. Here we consider the effect of growth phase (mid-log, late-log and late stationary phase) on Hg methylation by the known methylator Desulfovibrio desulfuricans ND132. We tested the addition of Hg alone (chloride-complex), Hg with Suwannee River natural organic matter (SRNOM) (unequilibrated), and Hg equilibrated with SRNOM on monomethylmercury (MMHg) production by ND132 over a growth curve in pyruvate fumarate media. This NOM did not affect MMHg production even under very low Hg: SRNOM ratios, where Hg binding is predicted to be dominated by high energy sites. Adding Hg or Hg NOM to growing cultures 24 h before sampling (late addition) resulted in ~2 greater net fraction of Hg methylated than for comparably aged cultures exposed to Hg from the initial culture inoculation (early addition). Mid-and late-log phase cultures produced similar amounts of MMHg, but late stationary phase cultures (both under early and late Hg addition conditions) produced up to ~3 more MMHg, indicating the potential importance of growth phase in studies of MMHg production.

  11. Gas-Phase Oxidation, Particle Uptake, and Product Studies of Isoprene Epoxydiols

    NASA Astrophysics Data System (ADS)

    Bates, K. H.; Nguyen, T. B.; St Clair, J. M.; Crounse, J.; Zhang, X.; Coggon, M.; Schwantes, R.; Bennett, N.; Stoltz, B.; Wennberg, P. O.; Seinfeld, J.

    2013-12-01

    Isoprene epoxydiols (IEPOX), discovered in 2009 as low-NOx atmospheric oxidation products of the ubiquitous biogenic precursor isoprene, are key intermediates in the formation of secondary organic aerosol (SOA) from biogenic emissions. Recent studies carried out in the Caltech environmental chambers have elucidated the gas-phase OH oxidation rates and products, particle uptake rates, and particle-phase OH oxidation products of three isomers of IEPOX synthesized in-house. Gas-phase oxidation studies were conducted in 1 m3 chambers at both high- and low-NOx conditions, and were monitored by GC-FID, two types of chemical ionization mass spectrometry (CIMS), and GC-CIMS. Comparisons with previous studies on isoprene showed that the two β-IEPOX isomers dominate over the ∂ isomers under atmospheric conditions, and the use of propene as an internal standard provided a robust estimate of OH oxidation rates between 0.99*10-11 and 1.67*10-11 cm3molec-1s-1 for the three isomers. Particle uptake and oxidation studies were conducted in 28 m3 chambers, and were monitored by GC-FID, CIMS, an aerosol mass spectrometer (AMS), and a differential mobility analyzer (DMA). Particle uptake showed a strong dependence on humidity, with no uptake on dry seed, and was faster on ammonium sulfate seed than sodium chloride seed. Particle-phase oxidation gave similar products to gas-phase oxidation by OH radicals.

  12. Land application uses for dry FGD by-products, Phase 1 report

    SciTech Connect

    Bigham, J.; Dick, W.; Forster, L.; Hitzhusen, F.; McCoy, E.; Stehouwer, R.; Traina, S.; Wolfe, W.

    1993-04-01

    The 1990 amendments to the Clean Air Act have spurred the development of flue gas desulfurization (FGD) processes, several of which produce a dry, solid by-product material consisting of excess sorbent, reaction products containing sulfates and sulfites, and coal fly ash. FGD by-product materials are treated as solid wastes and must be landfilled. It is highly desirable to find beneficial reuses for these materials provided the environmental impacts are minimal and socially acceptable. Phase 1 results of a 4 and 1/2 year study to demonstrate large volume beneficial uses of FGD by-products are reported. The purpose of the Phase 1 portion of the project was to characterize the chemical, physical, mineralogical and engineering properties of the FGD by-product materials obtained from various FGD technologies being developed in the state of Ohio. Phase 1 also involved the collection of baseline economic data related to the beneficial reuse of these FGD materials. A total of 58 samples were collected and analyzed. The results indicated the chemical composition of the FGD by-product materials were dominated by Ca, S, Al, and Si. Many of the elements regulated by the US Environmental Protection Agency reside primarily in the fly ash. Phase 1 results revealed that FGD by-product materials are essentially coal fly ash materials diluted with unreacted sorbent and reaction products. High volume beneficial reuses will depend on the economics of their substituting for existing materials for various types of applications (e.g. as an agricultural liming material, soil borrow for highway embankment construction, and reclamation of active and abandoned surface coal mines). Environmental constraints to the beneficial reuse of dry FGD by-product materials, based on laboratory and leachate studies, seem to be less than for coal fly ash.

  13. 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.

  14. Gas-phase products and secondary aerosol yields from the photooxidation of 16 different terpenes

    NASA Astrophysics Data System (ADS)

    Lee, Anita; Goldstein, Allen H.; Kroll, Jesse H.; Ng, Nga L.; Varutbangkul, Varuntida; Flagan, Richard C.; Seinfeld, John H.

    2006-09-01

    The photooxidation of isoprene, eight monoterpenes, three oxygenated monoterpenes, and four sesquiterpenes were conducted individually at the Caltech Indoor Chamber Facility under atmospherically relevant HC:NOx ratios to monitor the time evolution and yields of SOA and gas-phase oxidation products using PTR-MS. Several oxidation products were calibrated in the PTR-MS, including formaldehyde, acetaldehyde, formic acid, acetone, acetic acid, nopinone, methacrolein + methyl vinyl ketone; other oxidation products were inferred from known fragmentation patterns, such as pinonaldehyde; and other products were identified according to their mass to charge (m/z) ratio. Numerous unidentified products were formed, and the evolution of first- and second-generation products was clearly observed. SOA yields from the different terpenes ranged from 1 to 68%, and the total gas- plus particle-phase products accounted for ˜50-100% of the reacted carbon. The carbon mass balance was poorest for the sesquiterpenes, suggesting that the observed products were underestimated or that additional products were formed but not detected by PTR-MS. Several second-generation products from isoprene photooxidation, including m/z 113, and ions corresponding to glycolaldehyde, hydroxyacetone, methylglyoxal, and hydroxycarbonyls, were detected. The detailed time series and relative yields of identified and unidentified products aid in elucidating reaction pathways and structures for the unidentified products. Many of the unidentified products from these experiments were also observed within and above the canopy of a Ponderosa pine plantation, confirming that many products of terpene oxidation can be detected in ambient air using PTR-MS, and are indicative of concurrent SOA formation.

  15. Nectar Sugar Production across Floral Phases in the Gynodioecious Protandrous Plant Geranium sylvaticum

    PubMed Central

    Varga, Sandra; Nuortila, Carolin; Kytöviita, Minna-Maarit

    2013-01-01

    Many zoophilous plants attract their pollinators by offering nectar as a reward. In gynodioecious plants (i.e. populations are composed of female and hermaphrodite individuals) nectar production has been repeatedly reported to be larger in hermaphrodite compared to female flowers even though nectar production across the different floral phases in dichogamous plants (i.e. plants with time separation of pollen dispersal and stigma receptivity) has rarely been examined. In this study, sugar production in nectar standing crop and secretion rate were investigated in Geranium sylvaticum, a gynodioecious plant species with protandry (i.e. with hermaphrodite flowers releasing their pollen before the stigma is receptive). We found that flowers from hermaphrodites produced more nectar than female flowers in terms of total nectar sugar content. In addition, differences in nectar production among floral phases were found in hermaphrodite flowers but not in female flowers. In hermaphrodite flowers, maximum sugar content coincided with pollen presentation and declined slightly towards the female phase, indicating nectar reabsorption, whereas in female flowers sugar content did not differ between the floral phases. These differences in floral reward are discussed in relation to visitation patterns by pollinators and seed production in this species. PMID:23614053

  16. The Production Phase for the National Compact Stellarator Experiment (NCSX) Modular Coil Winding Forms

    SciTech Connect

    Heitzenroeder, P.; Brown, T.; Neilson, G.; Malinowski, F.; Sutton, L.; Nelson, B.; Williamson, D.; Horton, N.; Goddard, B.; Edwards, J.; Bowling, K.; Hatzilias, K.

    2005-10-20

    The production phase for the NCSX modular coil winding forms has been underway for approximately one year as of this date. This is the culmination of R&D efforts performed in 2001-4. The R&D efforts included limited manufacturing studies while NCSX was in its conceptual design phase followed by more detailed manufacturing studies by two teams which included the fabrication of full scale prototypes. This provided the foundation necessary for the production parts to be produced under a firm price and schedule contract that was issued in September 2004. This paper will describe the winding forms, the production team and team management, details of the production process, and the achievements for the first year.

  17. Chemical characterization of the main products formed through aqueous-phase photonitration of guaiacol

    NASA Astrophysics Data System (ADS)

    Kitanovski, Z.; Čusak, A.; Grgić, I.; Claeys, M.

    2014-08-01

    Guaiacol (2-methoxyphenol) and its derivatives can be emitted into the atmosphere by thermal degradation (i.e., burning) of wood lignins. Due to its volatility, guaiacol is predominantly distributed atmospherically in the gaseous phase. Recent studies have shown the importance of aqueous-phase reactions in addition to the dominant gas-phase and heterogeneous reactions of guaiacol, in the formation of secondary organic aerosol (SOA) in the atmosphere. The main objectives of the present study were to chemically characterize the main products of the aqueous-phase photonitration of guaiacol and examine their possible presence in urban atmospheric aerosols. The aqueous-phase reactions were carried out under simulated sunlight and in the presence of hydrogen peroxide and nitrite. The formed guaiacol reaction products were concentrated by solid-phase extraction and then purified with semi-preparative high-performance liquid chromatography (HPLC). The fractionated individual compounds were isolated as pure solids and further analyzed with liquid-state proton, carbon-13 and two-dimensional nuclear magnetic resonance (NMR) spectroscopy, and direct infusion negative ion electrospray ionization tandem mass spectrometry ((-)ESI-MS/MS). The NMR and product ion (MS2) spectra were used for unambiguous product structure elucidation. The main products of guaiacol photonitration are 4-nitroguaiacol (4NG), 6-nitroguaiacol (6NG), and 4,6-dinitroguaiacol (4,6DNG). Using the isolated compounds as standards, 4NG and 4,6DNG were unambiguously identified in winter PM10 aerosols from the city of Ljubljana (Slovenia) by means of HPLC/(-)ESI-MS/MS. Owing to the strong absorption of ultraviolet and visible light, 4,6DNG could be an important constituent of atmospheric "brown" carbon, especially in regions affected by biomass burning.

  18. Sintered rare earth-iron Laves phase magnetostrictive alloy product and preparation thereof

    DOEpatents

    Malekzadeh, Manoochehr; Pickus, Milton R.

    1979-01-01

    A sintered rare earth-iron Laves phase magnetostrictive alloy product characterized by a grain oriented morphology. The grain oriented morphology is obtained by magnetically aligning powder particles of the magnetostrictive alloy prior to sintering. Specifically disclosed are grain oriented sintered compacts of Tb.sub.x Dy.sub.1-x Fe.sub.2 and their method of preparation. The present sintered products have enhanced magnetostrictive properties.

  19. Land application uses for dry flue gas desulfurization by-products: Phase 2. Final report

    SciTech Connect

    Stehouwer, R.; Dick, W.; Bigham, J.

    1998-03-01

    The Clean Air Act, as amended in 1990, spurred the development of flue gas desulfurization (FGD) technologies, several of which produce a dry, solid by-product material consisting of excess sorbent, reaction products containing sulfates and sulfites, and coal fly ash. A three-phase study was initiated in December 1990 to demonstrate high-volume beneficial uses of FGD by-products as alternates to landfilling. Phase 1 characterized the chemical, physical, mineralogical, and engineering properties of FGD by-products from 13 coal-fired boilers, and provided a preliminary evaluation of the economic feasibility of various FGD by-product applications. This report covers Phase 2 of the study, which included (1) laboratory and greenhouse studies to evaluate the use of dry FGD by-products as a soil conditioning amendment for acidic minespoils and agricultural soils, (2) field studies to test several high-volume agronomic and engineering uses, and (3) development and preliminary application of a basic methodological framework for estimation of the economic costs and benefits to society of various beneficial reuse options.

  20. Multi-objective optimization approach for cost management during product design at the conceptual phase

    NASA Astrophysics Data System (ADS)

    Durga Prasad, K. G.; Venkata Subbaiah, K.; Narayana Rao, K.

    2014-03-01

    The effective cost management during the conceptual design phase of a product is essential to develop a product with minimum cost and desired quality. The integration of the methodologies of quality function deployment (QFD), value engineering (VE) and target costing (TC) could be applied to the continuous improvement of any product during product development. To optimize customer satisfaction and total cost of a product, a mathematical model is established in this paper. This model integrates QFD, VE and TC under multi-objective optimization frame work. A case study on domestic refrigerator is presented to show the performance of the proposed model. Goal programming is adopted to attain the goals of maximum customer satisfaction and minimum cost of the product.

  1. Effect of production phase on bottle-fermented sparkling wine quality.

    PubMed

    Kemp, Belinda; Alexandre, Hervé; Robillard, Bertrand; Marchal, Richard

    2015-01-14

    This review analyzes bottle-fermented sparkling wine research at each stage of production by evaluating existing knowledge to identify areas that require future investigation. With the growing importance of enological investigation being focused on the needs of the wine production industry, this review examines current research at each stage of bottle-fermented sparkling wine production. Production phases analyzed in this review include pressing, juice adjustments, malolactic fermentation (MLF), stabilization, clarification, tirage, lees aging, disgorging, and dosage. The aim of this review is to identify enological factors that affect bottle-fermented sparkling wine quality, predominantly aroma, flavor, and foaming quality. Future research topics identified include regional specific varieties, plant-based products from vines, grapes, and yeast that can be used in sparkling wine production, gushing at disgorging, and methods to increase the rate of yeast autolysis. An internationally accepted sensory analysis method specifically designed for sparkling wine is required. PMID:25494838

  2. NATO/CCMS PILOT STUDY CLEAN PRODUCTS AND PROCESSES (PHASE II) 2003 ANNUAL REPORT

    EPA Science Inventory

    The 6th annual meeting of the NATO CCMS Pilot Study, Clean Products and Processes, was held in Cetraro, Italy, from May 11 to 15, 2003. This was also the first meeting of its Phase II study. 24 country representatives attended this meeting. This meeting was very ably run by th...

  3. RESONATORS, MODES, BEAMS: Gain saturation of laser beams and production and decay of phase dislocations

    NASA Astrophysics Data System (ADS)

    Malyutin, A. A.

    2006-02-01

    The distortion of the distribution of initially pure laser modes caused by the gain saturation is simulated numerically. It is shown that the gain saturation results in a considerable enrichment of the modal spectrum of radiation accompanied by the production and decay of phase dislocations in the far-field domain and at the output of an astigmatic π/2-mode converter.

  4. SOLID PHASE MICROEXTRACTION FOR TRACE LEVEL ANALYSIS OF DISINFECTION BY-PRODUCTS

    EPA Science Inventory

    This presentation focuses on the development of a solid-phase microextraction (SPME)-gas chromatography (GC)/ion trap mass spectrometry (MS) method for the analysis of semivolatile disinfection by-products (DBPs) in drinking water in the low ug/L range. These DBPs were selected ...

  5. Effects of inoculum size on solid-phase fermentation of fodder beets for fuel ethanol production

    SciTech Connect

    Gibbons, W.R.; Westby, C.A.

    1986-10-01

    This fuel ethanol study examined the effects of Saccharomyces cerevisiae inoculum size on solid-phase fermentation of fodder beet pulp. A 5% inoculum (wt/wt) resulted in rapid yeast and ethanol (9.1% (vol/vol)) production. Higher inocula showed no advantages. Lower inocula resulted in lowered final yeast populations and increased fermentation times.

  6. For cermet inert anode containing oxide and metal phases useful for the electrolytic production of metals

    DOEpatents

    Ray, Siba P.; Liu, Xinghua; Weirauch, Douglas A.

    2002-01-01

    A cermet inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode comprises a ceramic phase including an oxide of Ni, Fe and M, where M is at least one metal selected from Zn, Co, Al, Li, Cu, Ti, V, Cr, Zr, Nb, Ta, W, Mo, Hf and rare earths, preferably Zn and/or Co. Preferred ceramic compositions comprise Fe.sub.2 O.sub.3, NiO and ZnO or CoO. The cermet inert anode also comprises a metal phase such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. A preferred metal phase comprises Cu and Ag. The cermet inert anodes may be used in electrolytic reduction cells for the production of commercial purity aluminum as well as other metals.

  7. Phase transition of the one-dimensional coagulation-production process

    SciTech Connect

    Odor, Geza

    2001-06-01

    Recently an exact solution has been found by M. Henkel and H. Hinrichsen [J. Phys. A >34, 1561 (2001)] for the one-dimensional coagulation-production process: 2A{r_arrow}A, A0A{r_arrow}3A with equal diffusion and coagulation rates. This model evolves into the inactive phase independently of the production rate with t{sup {minus}1/2} density decay law. This paper shows that cluster mean-field approximations and Monte Carlo simulations predict a continuous phase transition for higher diffusion/coagulation rates as considered by the exact solution. Numerical evidence is given that the phase transition universality agrees with that of the annihilation-fission model with low diffusions.

  8. Land application uses for dry FGD by-products. Phase 2 report

    SciTech Connect

    Stehouwer, R.; Dick, W.; Bigham, J.

    1996-03-01

    A study was initiated in December 1990 to demonstrate large volume beneficial uses of flue gas desulfurization (FGD) by-products. A Phase 1 report provided results of an extensive characterization of chemical, physical, mineralogical and engineering properties of 58 dry FGD by-product samples. The Phase 1 report concluded that high volume beneficial reuses will depend on the economics related to their ability to substitute for existing materials for various types of applications (e.g. as an agricultural liming material, soil borrow for highway embankment construction, and reclamation of active and abandoned surface coal mine lands). Phase 2 objectives were (1) to conduct laboratory and greenhouse studies of FGD and soil (spoil) mixtures for agronomic and engineering applications, (2) to initiate field studies related to high volume agronomic and engineering uses, and (3) to develop the basic methodological framework for estimation of the financial and economic costs and benefits to society of several FGD reuse options and to make some preliminary runs of economic models. High volume beneficial reuses of dry FGD by-products have been successfully demonstrated. Adverse environmental impacts have been negligible. Although few sources of dry FGD by-products currently exist in Ohio and the United States there is potential for smaller coal-fired facilities to adopt S0{sub 2} scrubbing technologies that produce dry FGD material. Also much of what we have learned from studies on dry FGD by-products is applicable to the more prevalent wet FGD by-products. The adaptation of the technologies demonstrated in this project seem to be not only limited by economic constraints, but even more so, by the need to create awareness of the market potential of using these FGD by-products.

  9. Gas- and Particle-Phase Products from the Chlorine-Initiated Oxidation of Polycyclic Aromatic Hydrocarbons.

    PubMed

    Riva, Matthieu; Healy, Robert M; Flaud, Pierre-Marie; Perraudin, Emilie; Wenger, John C; Villenave, Eric

    2015-11-12

    The chlorine atom (Cl)-initiated oxidation of three polycyclic aromatic hydrocarbons (PAHs; namely, naphthalene, acenaphthylene, and acenaphthene) was investigated. Experiments were performed in an atmospheric simulation chamber using a proton transfer reaction time-of-flight mass spectrometer (TOF-MS) and an aerosol TOF-MS to characterize the oxidation products in the gas and particle phases, respectively. The major products identified from the reaction of Cl atoms with naphthalene were phthalic anhydride and chloronaphthalene, indicating that H atom abstraction and Cl addition reaction pathways are both important. Acenaphthenone was the principal product arising from reaction of Cl with acenaphthene, while 1,8-naphthalic anhydride, acenaphthenone, acenaphthenequinone, and chloroacenaphthenone were all identified as products of acenaphthylene oxidation, confirming that the cylcopenta-fused ring controls the reactivity of these PAHs toward Cl atoms. Possible reaction mechanisms are proposed for the formation of these products, and favored pathways have been suggested. Large yields of secondary organic aerosol (SOA) were also observed in all experiments, and the major products were found to undergo significant partitioning to the particle-phase. This work suggests that Cl-initiated oxidation could play an important role in SOA formation from PAHs under specific atmospheric conditions where the Cl atom concentration is high, such as the marine boundary layer. PMID:26472257

  10. Production of heralded pure single photons from imperfect sources using cross-phase-modulation

    SciTech Connect

    Konrad, Thomas; Nock, Michael; Scherer, Artur; Audretsch, Juergen

    2006-09-15

    Realistic single-photon sources do not generate single photons with certainty. Instead they produce statistical mixtures of photons in Fock states |1> and vacuum (noise). We describe how to eliminate the noise in the output of the sources by means of another noisy source or a coherent state and cross-phase-modulation (XPM). We present a scheme that announces the production of pure single photons and thus eliminates the vacuum contribution. This is done by verifying a XPM-related phase shift with a Mach-Zehnder interferometer.

  11. 30 CFR 203.34 - To which production may an RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false To which production may an RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my lease not be applied? 203.34 Section 203.34 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT RELIEF OR REDUCTION IN ROYALTY...

  12. Phase distribution and removal of pharmaceuticals and personal care products during anaerobic sludge digestion.

    PubMed

    Narumiya, Masanori; Nakada, Norihide; Yamashita, Naoyuki; Tanaka, Hiroaki

    2013-09-15

    The fate and removal of 48 pharmaceuticals and personal care products (PPCPs) during anaerobic digestion of sewage sludge were investigated in four full-scale sewage treatment plants (STPs). We measured concentrations in both the liquid and solid phases of the sludge to compare the distribution ratios (Kd) between phases before and after digestion. The results showed changes in Kd values of PPCPs with carboxyl or amino functional groups, probably due to a shift of dissociation equilibrium with the increase in pH. Sulfamethoxazole and trimethoprim were almost completely degraded (>90%); triclosan, triclocarban, and ofloxacin were moderately degraded (around 30-50%); but carbamazepine was not eliminated. To our knowledge, this is the first report that shows (i) the occurrence and removal of several tens of PPCPs by anaerobic sludge digestion in full-scale municipal STPs and (ii) the change of distribution between the liquid and solid phases during digestion. PMID:23774781

  13. Applications of liquid-phase microextraction techniques in natural product analysis: a review.

    PubMed

    Yan, Yunyan; Chen, Xuan; Hu, Shuang; Bai, Xiaohong

    2014-11-14

    Over the last years, liquid-phase microextraction (LPME) as a simple, rapid, practical and effective sample-preparation technique, coupled with various instrumental analytical methods, has been increasingly and widely used to research and determine trace or ultra-micro-levels of both inorganic and organic analytes from different matrix-complex samples. In this review, different kinds of LPMEs such as single drop liquid-phase microextraction, dispersive liquid-liquid microextraction, and hollow fibre liquid-phase microextraction are summarized and recent applications of LPMEs in trace compounds in vivo and in vitro from different natural product matrice analysis such as tea, vegetables, seeds, herbs, and galenical are also discussed. Finally, future developments and applications of LPMEs in complex sample analysis are prospected. PMID:25441339

  14. Novel module production methods for the CMS pixel detector, upgrade phase I

    NASA Astrophysics Data System (ADS)

    Blank, T.; Caselle, M.; Weber, M.; Kudella, S.; Colombo, F.; Hansen, K.; Arab, S.

    2015-02-01

    For the High-Luminosity upgrade of the LHC (HL-LHC), phase I, the CMS pixel detector needs to be replaced. In order to improve the tracking resolution even at high luminosity the pixel detector is upgraded by a fourth barrel layer. This paper describes the production process and results for the fourth barrel layer for the CMS silicon pixel detector, upgrade phase I. The additional barrel layer will be produced by KIT and DESY. Both research centers have commonly developed and investigated new production processes, including SAC solder bump jetting, gold stud bumping and "Precoat by Powder Processes" (PPS) to bump the sensor tiles and prepare them for the flip-chip process. First bare modules have been produced with the new digital ROC.

  15. Improved electroacoustic dewatering (EAD) belt press for food products. Phase 3, Technical progress report

    SciTech Connect

    Not Available

    1994-02-01

    Battelle`s electroacoustic dewatering (EAD) process improves the performance of mechanical dewatering processes for several food products (such as corn fiber) by superimposing electric and ultrasonic fields. EAD has the potential to save 0.027 to 0.035 quad/yr energy by 1995 in the food processing industry, which consumed 0.15 to 0.18 quad in 1986. This report covers Phase III for demonstrating the EAD prototype on corn wet milling products (corn fiber and gluten); only Task 1 (prototype preparation and planning) was completed. EAD performance was examined in the laboratory; availability of a test site was examined. The single-roll, postdewatering EAD belt press prototype can accept material predewatered by a screw press, centrifuge, or any other mechanical dewatering device. The two-belt system, utilizing a copper-polymer cathode belt, performed as well as the three-belt system used in Phase II.

  16. piRNA-Guided Transposon Cleavage Initiljates Zucchini-Dependent, Phased piRNA Production

    PubMed Central

    Han, Bo W; Wang, Wei; Li, Chengjian; Weng, Zhiping; Zamore, Phillip D.

    2015-01-01

    PIWI-interacting RNAs (piRNAs) protect the animal germline by silencing transposons. Primary piRNAs, generated from transcripts of genomic transposon ‘junkyards’ (piRNA clusters), are amplified by the “Ping-Pong” pathway, yielding secondary piRNAs. We report that secondary piRNAs, bound to the PIWI protein Ago3, can initiate primary piRNA production from cleaved transposon RNAs. The first ~26 nt of each cleaved RNA becomes a secondary piRNA, but the subsequent ~26 nt becomes the first in a series of phased primary piRNAs that bind Piwi, allowing piRNAs to spread beyond the site of RNA cleavage. The Ping-Pong pathway increases only the abundance of piRNAs, whereas production of phased primary piRNAs from cleaved transposon RNAs adds sequence diversity to the piRNA pool, allowing adaptation to changes in transposon sequence. PMID:25977554

  17. Yeast fermentation of carboxylic acids obtained from pyrolytic aqueous phases for lipid production.

    PubMed

    Lian, Jieni; Garcia-Perez, Manuel; Coates, Ralph; Wu, Hongwei; Chen, Shulin

    2012-08-01

    The presence of very reactive C1-C4 molecules adversely affects the quality bio-oils produced from the pyrolysis of lignocellulosic materials. In this paper a scheme to produce lipids with Cryptococcus curvatus from the carboxylic acids in the pyrolytic aqueous phase collected in fractional condensers is proposed. The capacities of three oleaginous yeasts C. curvatus, Rhodotorula glutinis, Lipomyces starkeyi to ferment acetate, formate, hydroxylacat-aldehyde, phenol and acetol were investigated. While acetate could be a good carbon source for lipid production, formate provides additional energy and contributes to yeast growth and lipid production as auxiliary energy resource. Acetol could slightly support yeast growth, but it inhibits lipid accumulation. Hydroxyacetaldehyde and phenols showed high yeast growth and lipid accumulation inhibition. A pyrolytic aqueous phase with 20 g/L acetate was fermented with C. curvatus, after neutralization and detoxification to produce 6.9 g/L dry biomass and 2.2 g/L lipid. PMID:22705522

  18. The Stability of CI02 as a Product of Gas Phase Decontamination Treatments

    SciTech Connect

    D. W. Simmons

    1994-09-01

    The gas phase decontamination project is investigating the use of chlorine trifluoride (ClF{sub 3}) to fluorinate nonvolatile uranium deposits to produce uranium hexafluoride (UF{sub 6}) gas. The potential existence of chlorine dioxide (ClO{sub 2}) during gas phase decontamination with ClF{sub 3} has been the subject of recent safety discussions. Some of the laboratory data collected during feasibility studies of the gas phase process has been evaluated for the presence of ClO{sub 2} in the product gas stream. The preliminary evidence to date can be summarized as follows: (1) ClO{sub 2} was not detected in the flow loop in the absence of ClF{sub 3}; (2) ClO{sub 2} was not detected in the static reactors in the absence of both ClF{sub 3} and ClF; and (3) ClO{sub 2} was detected in a static reactor in the absence of all fluorinating gases. The experimental evidence suggests that ClO{sub 2} will not exist in the presence of ClF{sub 3}, ClF, or UF{sub 6}. The data analyzed to date is insufficient to determine the stability of ClO{sub 2} in the presence of ClO{sub 2}F. Thermodynamic calculations of the ClF{sub 3} + H{sub 2}O system support the experimental evidence, and suggest that ClO{sub 2} will not exist in the presence of ClO{sub 2}F. Additional experimental efforts are needed to provide a better understanding of the gas phase ClF{sub 3} treatments and the product gases. However, preliminary evidence to date suggests that ClO{sub 2} should not be present as a product during the normal operations of the gas phase decontamination project.

  19. One-, two-, and three-phase flow during free-product recovery

    SciTech Connect

    Baker, R.S.

    1995-12-31

    An increasing variety of options is becoming available for recovering organic liquids from the subsurface following releases from leaking underground storage tanks, buried pipelines, and surface spills. Multiphase fluid flow in porous media during product recovery must be considered to optimize desired effects and minimize unintended consequences. Free-product recovery commonly focuses first on soils that are saturated with respect to nonaqueous-phase liquid (NAPL), especially when a substantial thickness of floating product is apparent in monitoring wells. This paper also addresses product recovery from soils that are unsaturated with respect to NAPL, such as in the transition zone between the water table and the capillary fringe. Considering both saturated and unsaturated soils, the available product recovery methods can generally be classified as those that aim to recover NAPL only; NAPL and water; and NAPL, water, and vapor. The corresponding flow processes, respectively, involve one, two, and three phases. Examples of these distinctly different approaches are presented, along with their applicability, advantages, and disadvantages.

  20. Microbial and sponge loops modify fish production in phase-shifting coral reefs.

    PubMed

    Silveira, Cynthia B; Silva-Lima, Arthur W; Francini-Filho, Ronaldo B; Marques, Jomar S M; Almeida, Marcelo G; Thompson, Cristiane C; Rezende, Carlos E; Paranhos, Rodolfo; Moura, Rodrigo L; Salomon, Paulo S; Thompson, Fabiano L

    2015-10-01

    Shifts from coral to algae dominance of corals reefs have been correlated to fish biomass loss and increased microbial metabolism. Here we investigated reef benthic and planktonic primary production, benthic dissolved organic carbon (DOC) release and bacterial growth efficiency in the Abrolhos Bank, South Atlantic. Benthic DOC release rates are higher while water column bacterial growth efficiency is lower at impacted reefs. A trophic model based on the benthic and planktonic primary production was able to predict the observed relative fish biomass in healthy reefs. In contrast, in impacted reefs, the observed omnivorous fish biomass is higher, while that of the herbivorous/coralivorous fish is lower than predicted by the primary production-based model. Incorporating recycling of benthic-derived carbon in the model through microbial and sponge loops explains the difference and predicts the relative fish biomass in both reef types. Increased benthic carbon release rates and bacterial carbon metabolism, but decreased bacterial growth efficiency could lead to carbon losses through respiration and account for the uncoupling of benthic and fish production in phase-shifting reefs. Carbon recycling by microbial and sponge loops seems to promote an increase of small-bodied fish productivity in phase-shifting coral reefs. PMID:25817914

  1. Clinical Development of a Cytomegalovirus DNA Vaccine: From Product Concept to Pivotal Phase 3 Trial

    PubMed Central

    Smith, Larry R.; Wloch, Mary K.; Chaplin, Jennifer A.; Gerber, Michele; Rolland, Alain P.

    2013-01-01

    2013 marks a milestone year for plasmid DNA vaccine development as a first-in-class cytomegalovirus (CMV) DNA vaccine enters pivotal phase 3 testing. This vaccine consists of two plasmids expressing CMV antigens glycoprotein B (gB) and phosphoprotein 65 (pp65) formulated with a CRL1005 poloxamer and benzalkonium chloride (BAK) delivery system designed to enhance plasmid expression. The vaccine’s planned initial indication under investigation is for prevention of CMV reactivation in CMV-seropositive (CMV+) recipients of an allogeneic hematopoietic stem cell transplant (HCT). A randomized, double-blind placebo-controlled phase 2 proof-of-concept study provided initial evidence of the safety of this product in CMV+ HCT recipients who underwent immune ablation conditioning regimens. This study revealed a significant reduction in viral load endpoints and increased frequencies of pp65-specific interferon-γ-producing T cells in vaccine recipients compared to placebo recipients. The results of this endpoint-defining trial provided the basis for defining the primary and secondary endpoints of a global phase 3 trial in HCT recipients. A case study is presented here describing the development history of this vaccine from product concept to initiation of the phase 3 trial. PMID:26344340

  2. Lignin solubilization and aqueous phase reforming for the production of aromatic chemicals and hydrogen.

    PubMed

    Zakzeski, Joseph; Weckhuysen, Bert M

    2011-03-21

    The solubilization and aqueous phase reforming of lignin, including kraft, soda, and alcell lignin along with sugarcane bagasse, at low temperatures (T≤498 K) and pressures (P≤29 bar) is reported for the first time for the production of aromatic chemicals and hydrogen. Analysis of lignin model compounds and the distribution of products obtained during the lignin aqueous phase reforming revealed that lignin was depolymerized through disruption of the abundant β-O-4 linkages and, to a lesser extent, the 5-5' carbon-carbon linkages to form monomeric aromatic compounds. The alkyl chains contained on these monomeric compounds were readily reformed to produce hydrogen and simple aromatic platform chemicals, particularly guaiacol and syringol, with the distribution of each depending on the lignin source. The methoxy groups present on the aromatic rings were subject to hydrolysis to form methanol, which was also readily reformed to produce hydrogen and carbon dioxide. The composition of the isolated yields of monomeric aromatic compounds and overall lignin conversion based on these isolated yields varied from 10-15% depending on the lignin sample, with the balance consisting of gaseous products and residual solid material. Furthermore, we introduce the use of a high-pressure autoclave with optical windows and an autoclave with ATR-IR sentinel for on-line in situ spectroscopic monitoring of biomass conversion processes, which provides direct insight into, for example, the solubilization process and aqueous phase reforming reaction of lignin. PMID:21246746

  3. Long-Term Column Leaching of Phase II Mercury Control Technology By-Products

    SciTech Connect

    Schroeder, K.T.; Cardone, C.R.; White, Fredrick; Rohar, P.C.; Kim, A.G

    2007-07-01

    An NETL research, development and demonstration program under DOE/Fossil Energy Innovations for Existing Plants is directed toward the improvement of the performance and economics of mercury control from coal-fired plants. The current Phase II of the RD&D program emphasizes the evaluation of performance and cost of control technologies through slip-stream and full scale field testing while continuing the development of novel concepts. One of the concerns of the NETL program is the fate of the captured flue gas mercury which is transferred to the condensed phase by-product stream. The stability of mercury and any co-captured elements in the by-products could have a large economic impact if it reduced by-product sales or increasing their disposal costs. As part of a greater characterization effort of Phase II facility baseline and control technology sample pairs, NETL in-house laboratories have performed continuous leaching of a select subset of the available sample pairs using four leachants: water (pH=5.7), dilute sulfuric acid (pH=1.2), dilute acetic acid (pH=2.9), and sodium carbonate (pH=11.1). This report describes results obtained for mercury, arsenic, and selenium during the 5-month leaching experiments.

  4. Validation of models for predicting formaldehyde concentrations in residences due to pressed wood products. Phase 1

    SciTech Connect

    Grot, R.A.; Silberstein, S.; Ishiguro, K.

    1985-09-01

    The interim report describes procedures and presents results of the first phase of a laboratory project undertaken at the National Bureau of Standards for the Consumer Product Safety Commission (CPSC). The purpose of the project is to assess the accuracy of emission and indoor-air-quality models to be used by CPSC in predicting formaldehyde (HCHO) concentrations in residences due to pressed-wood products made with urea-formaldehyde bonding resins, namely particleboard underlayment, hardwood-plywood paneling and medium-density fiberboard (MDF). In phase I, these products were characterized in medium-size dynamic measuring chambers by measuring their HCHO surface emission rates over a range of HCHO concentrations, at 23C and 50% RH. They were then installed in a two-room prototype house and the equilibrium HCHO concentrations were monitored as a function of air exchange rate. Excellent agreement was obtained between measured HCHO concentrations and those predicted by a mass-balance indoor air quality model. In the next phase, the study will be repeated at various different temperatures and relative humidities so that models predicting HCHO surface emission rate as a function of temperature and humidity can be tested.

  5. Gas-phase products and secondary organic aerosol formation from the ozonolysis and photooxidation of myrcene

    NASA Astrophysics Data System (ADS)

    Böge, Olaf; Mutzel, Anke; Iinuma, Yoshiteru; Yli-Pirilä, Pasi; Kahnt, Ariane; Joutsensaari, Jorma; Herrmann, Hartmut

    2013-04-01

    Terrestrial vegetation releases a great variety of volatile organic compounds (VOC) into the atmosphere. Monoterpenes, like myrcene, contribute significantly to this global biogenic VOC emission. In the atmosphere, monoterpenes rapidly undergo oxidation reactions by OH radicals (mainly during the daytime), NO3 radicals (mainly during the nighttime) and O3 to form multifunctional oxidation products. The products of these reactions are likely to be of low volatility and hence might lead to secondary organic aerosol (SOA) formation. In the present study, we report results from a series of chamber experiments performed in the LEAK chamber at TROPOS in which the gas-phase products and SOA yields obtained from myrcene O3 reactions with and without an OH radical scavenger as well as from the myrcene OH radical reaction in the presence of NOx have been measured. During the experiments the consumption of myrcene as well as the formation of gas-phase products was monitored using a proton transfer reaction mass spectrometer (PTR-MS). Ozone concentration was measured by an O3 monitor and the mixing ratios of nitrogen oxides were measured by a NOx monitor. Particle size distributions between 3-900 nm were monitored every 11 min using a differential mobility particle sizer (DMPS) system. In addition to the products observed by means of the PTR-MS by their m/z values, an identification of carbonylic compounds by their DNPH derivatives was performed. Beside low molecular mass products the formation of 4-vinyl-4-pentenal with a yield of 55 % in myrcene ozonolysis has been observed. The further oxidation of this major first generation product lead to the formation of two dicarbonylic products with m/z 113 and to SOA formation. The influence of the continuing oxidation of 4-vinyl-4-pentenal on SOA formation will be discussed in detail. The emergence of the gas-phase product hydroxyacetone as direct result of the myrcene ozone reaction will be mooted, because hydroxyacetone seems to

  6. Product energy deposition of CN + alkane H abstraction reactions in gas and solution phases

    NASA Astrophysics Data System (ADS)

    Glowacki, David R.; Orr-Ewing, Andrew J.; Harvey, Jeremy N.

    2011-06-01

    In this work, we report the first theoretical studies of post-transition state dynamics for reaction of CN with polyatomic organic species. Using electronic structure theory, a newly developed analytic reactive PES, a recently implemented rare-event acceleration algorithm, and a normal mode projection scheme, we carried out and analyzed quasi-classical and classical non-equilibrium molecular dynamics simulations of the reactions CN + propane (R1) and CN + cyclohexane (R2). For (R2), we carried out simulations in both the gas phase and in a CH2Cl2 solvent. Analysis of the results suggests that the solvent perturbations to the (R2) reactive free energy surface are small, leading to product energy partitioning in the solvent that is similar to the gas phase. The distribution of molecular geometries at the respective gas and solution phase variational association transition states is very similar, leading to nascent HCN which is vibrationally excited in both its CH stretching and HCN bending coordinates. This study highlights the fact that significant non-equilibrium energy distributions may follow in the wake of solution phase bimolecular reactions, and may persist for hundreds of picoseconds despite frictional damping. Consideration of non-thermal distributions is often neglected in descriptions of condensed-phase reactivity; the extent to which the present intriguing observations are widespread remains an interesting question.

  7. The early phase of /see symbol/ production development in adult Japanese learners of English.

    PubMed

    Saito, Kazuya; Munro, Murray J

    2014-12-01

    Although previous research indicates that Japanese speakers' second language (L2) perception and production of English /see symbol/ may improve with increased L2 experience, relatively little is known about the fine phonetic details of their /see symbol/ productions, especially during the early phase of L2 speech learning. This cross-sectional study examined acoustic properties of word-initial /see symbol/ from 60 Japanese learners with a length of residence of between one month and one year in Canada. Their performance was compared to that of 15 native speakers of English and 15 low-proficiency Japanese learners of English. Formant frequencies (F2 and F3) and F1 transition durations were evaluated under three task conditions--word reading, sentence reading, and timed picture description. Learners with as little as two to three months of residence demonstrated target-like F2 frequencies. In addition, increased LOR was predictive of more target-like transition durations. Although the learners showed some improvement in F3 as a function of LOR, they did so mainly at a controlled level of speech production. The findings suggest that during the early phase of L2 segmental development, production accuracy is task-dependent and is influenced by the availability of L1 phonetic cues for redeployment in L2. PMID:25536843

  8. Entropy Production in Collisionless Systems. II. Arbitrary Phase-space Occupation Numbers

    NASA Astrophysics Data System (ADS)

    Barnes, Eric I.; Williams, Liliya L. R.

    2012-04-01

    We present an analysis of two thermodynamic techniques for determining equilibria of self-gravitating systems. One is the Lynden-Bell (LB) entropy maximization analysis that introduced violent relaxation. Since we do not use the Stirling approximation, which is invalid at small occupation numbers, our systems have finite mass, unlike LB's isothermal spheres. (Instead of Stirling, we utilize a very accurate smooth approximation for ln x!.) The second analysis extends entropy production extremization to self-gravitating systems, also without the use of the Stirling approximation. In addition to the LB statistical family characterized by the exclusion principle in phase space, and designed to treat collisionless systems, we also apply the two approaches to the Maxwell-Boltzmann (MB) families, which have no exclusion principle and hence represent collisional systems. We implicitly assume that all of the phase space is equally accessible. We derive entropy production expressions for both families and give the extremum conditions for entropy production. Surprisingly, our analysis indicates that extremizing entropy production rate results in systems that have maximum entropy, in both LB and MB statistics. In other words, both thermodynamic approaches lead to the same equilibrium structures.

  9. ENTROPY PRODUCTION IN COLLISIONLESS SYSTEMS. II. ARBITRARY PHASE-SPACE OCCUPATION NUMBERS

    SciTech Connect

    Barnes, Eric I.; Williams, Liliya L. R. E-mail: llrw@astro.umn.edu

    2012-04-01

    We present an analysis of two thermodynamic techniques for determining equilibria of self-gravitating systems. One is the Lynden-Bell (LB) entropy maximization analysis that introduced violent relaxation. Since we do not use the Stirling approximation, which is invalid at small occupation numbers, our systems have finite mass, unlike LB's isothermal spheres. (Instead of Stirling, we utilize a very accurate smooth approximation for ln x{exclamation_point}.) The second analysis extends entropy production extremization to self-gravitating systems, also without the use of the Stirling approximation. In addition to the LB statistical family characterized by the exclusion principle in phase space, and designed to treat collisionless systems, we also apply the two approaches to the Maxwell-Boltzmann (MB) families, which have no exclusion principle and hence represent collisional systems. We implicitly assume that all of the phase space is equally accessible. We derive entropy production expressions for both families and give the extremum conditions for entropy production. Surprisingly, our analysis indicates that extremizing entropy production rate results in systems that have maximum entropy, in both LB and MB statistics. In other words, both thermodynamic approaches lead to the same equilibrium structures.

  10. Hydrothermal transformation of Chinese privet seed biomass to gas-phase and semi-volatile products.

    PubMed

    Eberhardt, Thomas L; Catallo, W James; Shupe, Todd F

    2010-06-01

    Hydrothermal (HT) treatment of seeds from Chinese privet (Ligustrum sinense), a non-native and invasive species in the southeastern United States, was examined with respect to the generation of gas-phase and semi-volatile organic chemicals of industrial importance from a lipid-rich biomass resource. Aqueous seed slurries were transformed into biphasic liquid systems comprised of a milky aqueous phase overlain by a black organic layer. Present in the headspace were elevated levels of CO(2) and acetic acid. Analysis of the semi-volatiles by GC-MS showed the formation of alkyl substituted benzenes, oxygenated cyclic alkenes, phenol, substituted phenolics, and alkyl substituted pyridines. Compared to immature seeds, mature seeds gave high relative amounts of oxygenated cyclic alkenes (cyclopentenones) and alkyl pyridines. The presence of fatty acids in the HT products likely resulted from both lipid hydrolysis reactions and the inherent stability of fatty acids under HT treatment conditions. Estimates of lignin and protein contents showed no definite trend that could be linked to the HT data. The proportion of aromatic HT products appeared to derive primarily from the proportion of extractives. Thus, variations in extractives yields impact HT product yields and thereby demonstrate the importance of timing in feedstock collection to favor targeted HT products. PMID:20149648

  11. Repair, sidetrack, drilling, and completion of EE-2A for Phase 2 reservoir production service

    SciTech Connect

    Dreesen, D.S.; Cocks, G.G.; Nicholson, R.W.; Thomson, J.C.

    1989-08-01

    Hot Dry Rock (HDR) geothermal energy well EE-2 at Fenton Hill, New Mexico, was sidetracked and redrilled into the HDR Phase II reservoir after two unsuccessful attempts to repair damage in the lower wellbore. Before sidetracking was begun, six cement slurries were pumped to plug the abandoned lower wellbore and to support the production casing where drilling wear was predicted and where sidetracking was to occur. This work and the redrill of EE-2A were completed in November 1987. Specifications were prepared for a state-of-the-art tie-back casing, which was procured, manufactured, and delivered to Fenton Hill in May 1988. The well was then completed in June 1988 for hot-water production service by cementing in a liner and the upper section of production casing and installing and cementing a tie-back casing string. 24 refs., 17 figs., 5 tabs.

  12. Production-data analysis of single-phase (gas) coalbed-methane wells

    SciTech Connect

    Clarkson, C.R.; Bustin, R.M.; Seidle, J.P.

    2007-06-15

    The current work illustrates how single-well production-data-analysis (PDA) techniques, such as type curve, flowing material balance (FMB), and pressure-transient (PT) analysis, may be altered to analyze single-phase CBM wells. Examples of how reservoir inputs to the PDA techniques and subsequent calculations are modified to account for CBM-reservoir behavior are given. This paper demonstrates, by simulated and field examples, that reasonable reservoir and stimulation estimates can be obtained from PDA of CBM reservoirs only if appropriate reservoir inputs (i.e., desorption compressibility, fracture porosity) are used in the analysis. As the field examples demonstrate, type-curve, FMB, and PT analysis methods for PDA are not used in isolation for reservoir-property estimation, but rather as a starting point for single-well and multiwell reservoir simulation, which is then used to history match and forecast CBM-well production (e.g., for reserves assignment). To study the effects of permeability anisotropy upon production, a 2D, single-phase, numerical CBM-reservoir simulator was constructed to simulate single-well production assuming various permeability-anisotropy ratios. Only large permeability ratios ({lt} 16:1) appear to have a significant effect upon single-well production characteristics. Multilayer reservoir characteristics may also be observed with CBM reservoirs because of vertical heterogeneity, or in cases where the coals are commingled with conventional (sandstone) reservoirs. In these cases, the type-curve, FMB, and PT analysis techniques are difficult to apply with confidence. Methods and tools for analyzing multilayer CBM (plus sand) reservoirs are presented. Using simulated and field examples, it is demonstrated that unique reservoir properties may be assigned to individual layers from commingled (multilayer) production in the simple two-layer case.

  13. Dilepton and/or photon production in heavy ion collisions and the QCD phase transition

    SciTech Connect

    Hung, C.M.; Shuryak, E.V.

    1997-07-01

    We study the electromagnetic production from highly excited hadronic matter created in heavy ion collisions. The rates include the usual lowest order processes in quark-gluon plasma plus the usual reactions in the hadronic phase, related with {rho},a{sub 1} mesons. The space-time integration is done using a hydrodynamical model. Conventional {bar q}q ({pi}{sup +}{pi}{sup {minus}}) annihilation in quark-gluon plasma and hadronic phase cannot explain the observed dilepton spectrum, especially that by the CERES experiment at CERN. A decreased {rho} mass can account for the observed effect, provided it shifts into the region of 0.4{endash}0.5 GeV near the phase transition. In order to test this hypothesis one should also look at the chiral partner of {rho}, the axial a{sub 1} meson: its mass must then behave similarly. Its decay a{sub 1}{r_arrow}{pi}e{sup +}e{sup {minus}} populates the low mass region seen in the same experiment. The results for direct photon production are below the current WA80 experimental bounds, for all variants considered. {copyright} {ital 1997} {ital The American Physical Society}

  14. Secondary organic aerosol (trans)formation through aqueous phase guaiacol photonitration: chemical characterization of the products

    NASA Astrophysics Data System (ADS)

    Grgić, Irena; Kitanovski, Zoran; Kroflič, Ana; Čusak, Alen

    2014-05-01

    One of the largest primary sources of organic aerosol in the atmosphere is biomass burning (BB) (Laskin et al. 2009); in Europe its contribution to annual mean of PM10 is between 3 and 14 % (Maenhaut et al. 2012). During the process of wood burning many different products are formed via thermal degradation of wood lignin. Hardwood burning produces mainly syringol (2,6-dimetoxyphenol) derivatives, while softwood burning exclusively guaiacol (2-methoxyphenol) and its derivatives. Taking into account physical properties of methoxyphenols only, their concentrations in atmospheric waters might be underestimated. So, their aqueous phase reactions can be an additional source of SOA, especially in regions under significant influence of wood combustion. An important class of compounds formed during physical and chemical aging of the primary BBA in the atmosphere is nitrocatechols, known as strong absorbers of UV and Vis light (Claeys et al. 2012). Very recently, methyl-nitrocatechols were proposed as suitable markers for highly oxidized secondary BBA (Iinuma et al. 2010, Kitanovski et al. 2012). In the present work, the formation of SOA through aqueous phase photooxidation and nitration of guaiacol was examined. The key objective was to chemically characterize the main low-volatility products and further to check their possible presence in the urban atmospheric aerosols. The aqueous phase reactions were performed in a thermostated reactor under simulated sunlight in the presence of H2O2 and nitrite. Guaiacol reaction products were first concentrated by solid-phase extraction (SPE) and then subjected to semi-preparative liquid chromatography.The main product compounds were fractionated and isolated as pure solids and their structure was further elucidated by using nuclear magnetic resonance spectroscopy (1H, 13C and 2D NMR) and direct infusion negative ion electro-spray ionization tandem mass spectrometry (( )ESI-MS/MS). The main photonitration products of guaiacol (4

  15. Re-utilization of Industrial CO2 for Algae Production Using a Phase Change Material

    SciTech Connect

    Joseph, Brian

    2013-12-31

    This is the final report of a 36-month Phase II cooperative agreement. Under this project, Touchstone Research Laboratory (Touchstone) investigated the merits of incorporating a Phase Change Material (PCM) into an open-pond algae production system that can capture and re-use the CO2 from a coal-fired flue gas source located in Wooster, OH. The primary objective of the project was to design, construct, and operate a series of open algae ponds that accept a slipstream of flue gas from a coal-fired source and convert a significant portion of the CO2 to liquid biofuels, electricity, and specialty products, while demonstrating the merits of the PCM technology. Construction of the pilot facility and shakedown of the facility in Wooster, OH, was completed during the first two years, and the focus of the last year was on operations and the cultivation of algae. During this Phase II effort a large-scale algae concentration unit from OpenAlgae was installed and utilized to continuously harvest algae from indoor raceways. An Algae Lysing Unit and Oil Recovery Unit were also received and installed. Initial parameters for lysing nanochloropsis were tested. Conditions were established that showed the lysing operation was effective at killing the algae cells. Continuous harvesting activities yielded over 200 kg algae dry weight for Ponds 1, 2 and 4. Studies were conducted to determine the effect of anaerobic digestion effluent as a nutrient source and the resulting lipid productivity of the algae. Lipid content and total fatty acids were unaffected by culture system and nutrient source, indicating that open raceway ponds fed diluted anaerobic digestion effluent can obtain similar lipid productivities to open raceway ponds using commercial nutrients. Data were also collected with respect to the performance of the PCM material on the pilot-scale raceway ponds. Parameters such as evaporative water loss, temperature differences, and growth/productivity were tracked. The pond with the

  16. Milk cow feed intake and milk production and distribution estimates for Phase 1

    SciTech Connect

    Beck, D.M.; Darwin, R.F.; Erickson, A.R.; Eckert, R.L.

    1992-04-01

    This report provides initial information on milk production and distribution in the Hanford Environmental Dose Reconstruction (HEDR) Project Phase I study area. The Phase I study area consists of eight countries in central Washington and two countries in northern Oregon. The primary objective of the HEDR Project is to develop estimates of the radiation doses populations could have received from Hanford operations. The objective of Phase I of the project was to determine the feasibility of reconstructing data, models, and development of preliminary dose estimates received by people living in the ten countries surrounding Hanford from 1944 to 1947. One of the most important contributors to radiation doses from Hanford during the period of interest was radioactive iodine. Consumption of milk from cows that ate vegetation contaminated with iodine is likely the dominant pathway of human exposure. To estimate the doses people could have received from this pathway, it is necessary to estimate the amount of milk that the people living in the Phase I area consumed, the source of the milk, and the type of feed that the milk cows ate. The objective of the milk model subtask is to identify the sources of milk supplied to residents of each community in the study area as well as the sources of feeds that were fed to the milk cows. In this report, we focus on Grade A cow's milk (fresh milk used for human consumption).

  17. Production of Stabilized Virulence Factor-Negative Variants by Group A Streptococci during Stationary Phase

    PubMed Central

    Leonard, B. A. B.; Woischnik, M.; Podbielski, A.

    1998-01-01

    Many of the virulence factors associated with fulminant group A streptococci (GAS) infection are expressed under in vitro exponential growth conditions. However, the survival of GAS in tissue and intracellularly, as well as colonization of asymptomatic carriers, has been reported for GAS. The bacteria associated with these niches may encounter high-density, low-nutrient-flowthrough conditions that may more closely mimic in vitro stationary-phase conditions than exponential growth. Therefore, the behavior of GAS in stationary-phase culture was examined. We observed that after 24 h in stationary phase, GAS serotypes M49 and M2 developed a unstable colony dimorphism of typical large and atypical small colonies. Between days 4 and 5, we isolated stabilized atypical small colonies which remained stable for up to nine passages (approximately 200 generations) on fresh medium before fully reverting to the large-colony phenotype. Upon analysis, the small colonies showed no difference in cell number per colony, growth rate, survival in prolonged stationary-phase culture, or antibiotic sensitivity. However, the small colonies showed decreased transcription of hyaluronic acid capsule, the global positive virulence factor regulator gene mga, the mga-regulated emm mRNA (M-protein structural gene), and speB (cysteine protease). Accordingly, the small colonies were completely sensitive in a traditional phagocytosis assay. The production of virulence factors and phagocytosis resistance of the small-colony isolates was recovered when, after several passages on fresh medium, the colony morphology began to revert. PMID:9673270

  18. Production of stabilized virulence factor-negative variants by group A streptococci during stationary phase.

    PubMed

    Leonard, B A; Woischnik, M; Podbielski, A

    1998-08-01

    Many of the virulence factors associated with fulminant group A streptococci (GAS) infection are expressed under in vitro exponential growth conditions. However, the survival of GAS in tissue and intracellularly, as well as colonization of asymptomatic carriers, has been reported for GAS. The bacteria associated with these niches may encounter high-density, low-nutrient-flowthrough conditions that may more closely mimic in vitro stationary-phase conditions than exponential growth. Therefore, the behavior of GAS in stationary-phase culture was examined. We observed that after 24 h in stationary phase, GAS serotypes M49 and M2 developed a unstable colony dimorphism of typical large and atypical small colonies. Between days 4 and 5, we isolated stabilized atypical small colonies which remained stable for up to nine passages (approximately 200 generations) on fresh medium before fully reverting to the large-colony phenotype. Upon analysis, the small colonies showed no difference in cell number per colony, growth rate, survival in prolonged stationary-phase culture, or antibiotic sensitivity. However, the small colonies showed decreased transcription of hyaluronic acid capsule, the global positive virulence factor regulator gene mga, the mga-regulated emm mRNA (M-protein structural gene), and speB (cysteine protease). Accordingly, the small colonies were completely sensitive in a traditional phagocytosis assay. The production of virulence factors and phagocytosis resistance of the small-colony isolates was recovered when, after several passages on fresh medium, the colony morphology began to revert. PMID:9673270

  19. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  20. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  1. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  2. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  3. 40 CFR 82.7 - Grant and phase reduction of baseline production and consumption allowances for class I...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... production and consumption allowances for class I controlled substances. 82.7 Section 82.7 Protection of... OZONE Production and Consumption Controls § 82.7 Grant and phase reduction of baseline production and consumption allowances for class I controlled substances. For each control period specified in the...

  4. Phase 1 of the North Site cleanup: Definition of product streams. Volume 1

    SciTech Connect

    Sorini, S.; Merriam, N.

    1994-03-01

    Various materials and equipment have accumulated at the Western Research Institute (WRI) North Site Facility since its commissioning in 1968. This facility was built by the US Bureau of Mines, transferred to the US Energy Research Development Administration (ERDA) in 1976, and transferred once again to the US Department of Energy (DOE) shortly thereafter. In 1983, the North Site Facility became part of WRI. The materials that have accumulated over the years at the site have been stored in drums, tanks, and open piles. They vary from oil shale, tar sand, and coal feedstocks to products and materials associated with in situ simulation and surface process developments associated with these feedstocks. The majority of these materials have been associated with DOE North Site activities and work performed at the North Site under DOE-WRI cooperative agreement contracts. In phase I of the North Site Facility cleanup project, these materials were sampled and evaluated to determine their chemical characteristics for proper disposal or use in accordance with current local, state, and federal regulations. Phase I of the North Site Facility cleanup project involved dividing the stored materials into product streams and dividing each product stream into composite groups. Composite groups contain materials known to be similar in composition, source, and process exposure. For each composite group, materials, which are representative of the composite, were selected for sampling, compositing, and analysis.

  5. Effect of DMMP on the pyrolysis products of polyurethane foam materials in the gaseous phase

    NASA Astrophysics Data System (ADS)

    Liu, W.; Li, F.; Ge, X. G.; Zhang, Z. J.; He, J.; Gao, N.

    2016-07-01

    Dimethyl methylphosphonate (DMMP) has been used as a flame retardant containing phosphorus to decrease the flammability of the polyurethane foam material (PUF). Flame retardancy and thermal degradation of PUF samples have been investigated by the LOI tests and thermal analysis. The results show that LOI values of all PUF/DMMP samples are higher than that of the neat PUF sample and the LOI value of the samples increases with both DMMP concentration and the %P value. Thermal analysis indicates that flame retardant PUF shows a dominant condensed flame retardant activity during combustion. Thermogravimetric analysis-infrared spectrometry (TG-FTIR) has been used to study the influence of DMMP on the pyrolysis products in the gaseous phase during the thermal degradation of the PUF sample. Fourier transform infrared spectrometry (FTIR) spectra of the PUF sample at the maximum evolution rates and the generated trends of water and the products containing -NCO have been examined to obtain more information about the pyrolysis product evolutions of the samples at high temperature. These results reveal that although DMMP could improve the thermal stability of PUF samples through the formation of the residual char layer between fire and the decomposed materials, the influence of DMMP on the gaseous phase can be also observed during the thermal degradation process of materials.

  6. Mass spectrometry studies of fission product behavior: 2, Gas phase species

    SciTech Connect

    Blackburn, P.E.; Johnson, C.E.

    1987-01-01

    Revaporization of fission products from reactor system surfaces has become a complicating factor in source term definition. Critical to this phenomena is understanding the nature and behavior of the vapor phase species. This study characterizes the stability of the CsI . CsOH vapor phase complex. Vapor pressures were measured with a mass spectrometer. Thermodynamic data were obtained for CsOH(g), Cs/sub 2/(OH)/sub 2/(g), CsI(g), Cs/sub 2/I/sub 2/(g) and CsI . CsOH(g). Activity coefficients were derived for the CsI-CsOH system. The relative ionization cross section of CsOH is about ten times the cross section of CsI(g). CsI . CsOH fragments to Cs/sub 2/OH/sup +/ and an iodine atom. 17 refs., 4 figs., 6 tabs.

  7. Tracer dilution measurements for two-phase geothermal production: Comparative testing and operating experience

    SciTech Connect

    Hirtz, P.; Lovekin, J.

    1995-12-31

    The tracer dilution technique for the measurement of steam and water mass flowrates and total enthalpy of two-phase geothermal fluids has been in routine use in the U.S.A. for almost three years. The tracer technique was first tested and adopted on a field-wide basis at the Coso geothermal field in California. Validation of the method was performed at the Roosevelt Hot Springs geothermal project in Utah and the Salton Sea and Heber geothermal projects in California by direct comparison to orifice-plate flowmeter measurements of the separated phases. Production well mass flowrates and total enthalpy are now regularly measured by this technique in the Coso, Salton Sea and Heber geothermal fields. Implementation of the tracer method is currently underway for the Tiwi and Bulalo geothermal fields in the Philippines. This paper presents the conceptual design of the measurement process, the results of field validations, and operating experience during field-wide testing in Coso.

  8. Gas-Phase Reactions of Methoxyphenols with NO3 Radicals: Kinetics, Products, and Mechanisms.

    PubMed

    Zhang, Haixu; Yang, Bo; Wang, Youfeng; Shu, Jinian; Zhang, Peng; Ma, Pengkun; Li, Zhen

    2016-03-01

    Methoxyphenols, a group of important tracers for wood smoke, are emitted to the atmosphere in large quantities, but their transformations are rarely studied. In this study, the kinetics and products of the gas-phase reactions of eugenol and 4-ethylguaiacol with NO3 radicals were investigated online using a vacuum ultraviolet photoionization gas time-of-flight mass spectrometer. The rate coefficients of the gaseous reactions of eugenol and 4-ethylguaiacol with NO3 radicals were (1.6 ± 0.4) × 10(-13) and (1.1 ± 0.2) × 10(-12) cm(3) molecule(-1) s(-1) (at 298 K), indicating that the atmospheric lifetimes of the NO3 radicals were 3.5 and 0.5 h, respectively. With the aid of gas-chromatography-mass-spectrometry analysis, several types of degradation products were identified with nitro derivatives as the major products. The configurations of the nitro-product isomers and their formation mechanisms were determined via theoretical calculations. On the basis of these products, degradation pathways of the methoxyphenols with NO3 radicals were proposed. This study determines the degradation rates and mechanisms of the methoxyphenols at night and implies the significant NO3 nighttime chemistry. PMID:26845070

  9. Mechanisms of zinc incorporation in aluminosilicate crystalline structures and the leaching behaviour of product phases.

    PubMed

    Tang, Yuanyuan; Shih, Kaimin

    2015-01-01

    This study quantitatively evaluates a waste-to-resource strategy of blending zinc-laden sludge and clay material for low-cost ceramic products. Using ZnO as the simulated zinc-laden sludge to sinter with kaolinite, both zinc aluminate spinel (ZnAl₂O₄) and willemite (Zn₂SiO₄) phases were formed during the sintering process. To analyse the details of zinc incorporation reactions, γ-Al₂O₃and quartz were further used as precursors to observe ZnAl₂O₄and Zn₂SiO₄formations. By firing the ZnO mixtures and their corresponding precursors at 750-1350°C for 3 h, the efficiency of zinc transformation was determined through Rietveld refinement analyses of X-ray diffraction data. The results also show different incorporation behaviour for kaolinite and mullite precursors during the formation of ZnAl2O₄and Zn2SiO₄in the system. In addition, with a competitive formation between ZnAl₂O₄and Zn₂SiO₄, the ZnAl₂O₄spinel phase is predominant at temperatures higher than 1050°C. This study used a prolonged leaching test modified from the US Environmental Protection Agency's toxicity characteristic leaching procedure to evaluate ZnO, ZnAl₂O₄, and Zn₂SiO₄product phases. The zinc concentrations in ZnO and Zn₂SiO₄leachates were about two orders of magnitude higher than that of ZnAl₂O₄ leachate at the end of the experiment, indicating that ZnAl₂O₄formation is the preferred stabilization mechanism for incorporating zinc in ceramic products. PMID:25399963

  10. A New Process for Hot Metal Production at Low Fuel Rate - Phase 1 Feasibility Study

    SciTech Connect

    Dr. Wei-Kao Lu

    2006-02-01

    The project is part of the continuing effort by the North American steel industry to develop a coal-based, cokeless process for hot metal production. The objective of Phase 1 is to determine the feasibility of designing and constructing a pilot scale facility with the capacity of 42,000 mtpy of direct reduced iron (DRI) with 95% metallization. The primary effort is performed by Bricmont, Inc., an international engineering firm, under the supervision of McMaster University. The study focused on the Paired Straight Hearth furnace concept developed previously by McMaster University, The American Iron and Steel Institute and the US Department of Energy.

  11. Liquid phase methanol reactor staging process for the production of methanol

    DOEpatents

    Bonnell, Leo W.; Perka, Alan T.; Roberts, George W.

    1988-01-01

    The present invention is a process for the production of methanol from a syngas feed containing carbon monoxide, carbon dioxide and hydrogen. Basically, the process is the combination of two liquid phase methanol reactors into a staging process, such that each reactor is operated to favor a particular reaction mechanism. In the first reactor, the operation is controlled to favor the hydrogenation of carbon monoxide, and in the second reactor, the operation is controlled so as to favor the hydrogenation of carbon dioxide. This staging process results in substantial increases in methanol yield.

  12. Hydrogen and dry ice production through phase equilibrium separation and methane reforming

    NASA Astrophysics Data System (ADS)

    Posada, Alberto; Manousiouthakis, Vasilios

    A clean hydrogen (99.9999%) and dry ice production process is proposed, which is based on phase equilibrium (PE) separation and methane reforming. Heat and power integration studies are carried out for the proposed process, by formulating and solving the minimum hot/cold/electric utility cost problem for the associated heat exchange network. The optimum operating cost of the proposed process is shown to be lower than the corresponding cost of the conventional PSA (pressure swing adsorption) based process, if the produced dry ice is sold for as low as 2 cents kg-dry-ice -1 or if an equivalent CO 2 sequestration credit is conceded.

  13. 30 CFR 203.33 - To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my lease or in my unit? 203.33 Section 203.33 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT RELIEF OR REDUCTION IN...

  14. Quantum phase transitions in composite matrix product states of one-dimensional spin-1/2 chains

    NASA Astrophysics Data System (ADS)

    Zhu, Jing-Min

    2015-02-01

    For matrix product states of one-dimensional spin-1/2 chains, we investigate the properties of quantum phase transition of the proposed composite system. We find that the system has three different ferromagnetic phases, one line of the two ferromagnetic phases coexisting equally describes the paramagnetic state, and the other two lines of two ferromagnetic phases coexisting equally describe the ferrimagnetic states, while the three phases coexisting equally point describes the ferromagnetic state. Whether on phase transition lines or at the phase transition point, the system is always in an isolated mediate-coupling state, the physical quantities are discontinuous and the system has long-range correlation and has long-range classical correlation and long-range quantum correlation. We believe that our work is helpful for comprehensively and profoundly understanding the quantum phase transitions, and of some certain guidance and enlightening on the classification and measure of quantum correlation of quantum many-body systems.

  15. Aqueous Phase Photo-Oxidation of Succinic Acid: Changes in Hygroscopic Properties and Reaction Products

    NASA Astrophysics Data System (ADS)

    Hudson, P. K.; Ninokawa, A.; Hofstra, J.; de Lijser, P.

    2013-12-01

    Atmospheric aerosol particles have been identified as important factors in understanding climate change. The extent to which aerosols affect climate is determined, in part, by hygroscopic properties which can change as a result of atmospheric processing. Dicarboxylic acids, components of atmospheric aerosol, have a wide range of hygroscopic properties and can undergo oxidation and photolysis reactions in the atmosphere. In this study, the hygroscopic properties of succinic acid aerosol, a non-hygroscopic four carbon dicarboxylic acid, were measured with a humidified tandem differential mobility analyzer (HTDMA) and compared to reaction products resulting from the aqueous phase photo-oxidation reaction of hydrogen peroxide and succinic acid. Reaction products were determined and quantified using gas chromatography-flame ionization detection (GC-FID) and GC-mass spectrometry (GC-MS) as a function of hydrogen peroxide:succinic acid concentration ratio and photolysis time. Although reaction products include larger non-hygroscopic dicarboxylic acids (e.g. adipic acid) and smaller hygroscopic dicarboxylic acids (e.g. malonic and oxalic acids), comparison of hygroscopic growth curves to Zdanovskii-Stokes-Robinson (ZSR) predictions suggests that the hygroscopic properties of many of the product mixtures are largely independent of the hygroscopicity of the individual components. This study provides a framework for future investigations to fully understand and predict the role of chemical reactions in altering atmospheric conditions that affect climate.

  16. Valorisation of wastewater from two-phase olive oil extraction in fired clay brick production.

    PubMed

    de la Casa, José A; Lorite, Miguel; Jiménez, Juan; Castro, Eulogio

    2009-09-30

    Wastewater issued from oil-washing stage (OWW) in the two-phase olive oil extraction method was used to replace fresh water in clay brick manufacture. The extrusion trials were performed with one of the ceramic bodies currently being used in a local brick factory for red facing bricks (RB) production. Fresh water or OWW was added to a final consistency of 2.4 kg/cm(2), the same value as used at industrial scale for this kind of clay mixture. Comparative results of technological properties of facing bricks are presented. Results show that the products obtained with olive oil wastewater are comparable to traditional ones in terms of extrusion performance and technological properties of end products. Even dry-bending strength of the body formed by wastewater improves by 33% compared to fresh water body. In addition, heating requirements can be reduced in the range 2.4-7.3% depending on the final product. This application can alleviate environmental impacts from the olive oil extraction industry and, at the same time, result in economic savings for the brick manufacturing industry. PMID:19395170

  17. Greater Green River Basin production improvement project, Phase 1: Site characterization report

    SciTech Connect

    DeJarnett, B.B.; Krystinik, L.F.; Mead, R.H.; Poe, S.C.

    1996-05-01

    Several tight, naturally-fractured, gas-productive formations in the Greater Green River Basin (GGRB) in Wyoming have been exploited using conventional vertical well technology. Typically, hydraulic fracture treatments must be performed in completing these wells to increase gas production rates to economic levels. However, with the maturation of horizontal drilling technology hydraulic fracture treatments may not be the most effective method for improving gas production from these tight reservoirs. Two of the most prolific tight gas reservoirs in the Green River Basin, the Frontier and the Mesaverde, are candidates for the application of horizontal well completion technology. The objective of the proposed project is to apply the DOE`s technical concept to the Second Frontier Formation on the western flank of the Rock Springs Uplift. Previous industry attempts to produce in commercial quantities from the Second Frontier Formation have been hampered by lack of understanding of both the in-situ natural fracture system and lack of adequate stimulation treatments. The proposed technical approach involves drilling a vertical characterization well to the Second Frontier Formation at a depth of approximately 16,000 ft. from a site located about 18 miles northwest of Rock Springs, Wyoming. Logging, coring, and well testing information from the vertical well will be used to design a hydraulic fracturing treatment and to assess the resulting production performance. Data from the vertical drilling phase will be used to design a 2,500 to 3,000-ft lateral wellbore which will be kicked off from the vertical hole and extend into the blanket marine sandstone bench of the Second Frontier Formation. The trajectory of this wellbore will be designed to intersect the maximum number of natural fractures to maximize production rates. Production testing of the resulting completion will provide an assessment of reserve potential related to horizontal lateral completions.

  18. Renewable stationary phase liquid magnetochromatography: determining aspartame and its hydrolysis products in diet soft drinks.

    PubMed

    Barrado, E; Rodríguez, J A; Castrillejo, Y

    2006-08-01

    A new chromatographic modality that does not require high pressures and also allows renewal of the stationary phase as desired is reported. The technique is based on a thin layer paramagnetic stationary phase (Fe3O4-SiO2) retained on the inner wall of a minicolumn through the action of an external magnetic field, which also plays an important role in separating the analytes. Accordingly, the name "renewable stationary phase liquid magnetochromatography", or RSP-LMC, has been proposed for it. The technique was used to separate and quantify the sugar substitute alpha-aspartame and its constituent amino acids (hydrolysis products), L-aspartic acid and L-phenylalanine, in diet fizzy soft drinks. When the results obtained for alpha-aspartame were compared with those obtained using HPLC as a reference method, no significant differences were observed. The system proposed is fully automated, making it an economic, competitive alternative to conventional methods of determining alpha-aspartame and its amino acid components. PMID:16633788

  19. Major Effects in the Thermodynamics of Detonation Products: Phase Segregation versus Ionic Dissociation

    SciTech Connect

    Bastea, S; Fried, L E

    2010-03-09

    Water (H{sub 2}O) and nitrogen (N{sub 2}) are major detonation products of high explosives and it has long been conjectured that they may phase segregate at high enough temperatures and pressures to influence detonation properties of common explosives. We analyze the phase diagram of H{sub 2}O-N{sub 2} mixtures using a thermodynamic theory for polar-nonpolar mixtures and find that phase segregation is unlikely to occur above approximately 1600K. Therefore, H{sub 2}O-N{sub 2} immiscibility is not likely to be relevant for detonation predictions. We propose instead that the high pressure ionic dissociation of water plays an important role in detonation, and model it using a new ionic thermodynamics. We employ this model in chemical equilibrium calculations of standard high explosives, e.g. PETN, HMX and RDX, and find that it performs very well under a wide range of conditions. Thus, although it may require further development, it is likely that explicitly ionic thermodynamics will become a standard tool for explosives modeling.

  20. GERDA phase II detectors: Behind the production and characterisation at low background conditions

    NASA Astrophysics Data System (ADS)

    Maneschg, Werner; Gerda Collaboration

    2013-08-01

    The low background GERmanium Detector Array (GERDA) at Laboratori Nazionali del Gran Sasso (LNGS) is designed to search for the rare neutrinoless double beta decay (0νββ) in 76Ge. Bare germanium diodes are operated in liquid argon which is used as coolant, as passive and soon active as well shield against external radiation. Currently, Phase I of the experiment is running using ˜15 kg of co-axial High Purity Germanium diodes. In order to increase the sensitivity of the experiment 30 Broad Energy Germanium (BEGe) diodes will be added within 2013. This presentation reviews the production chain of the new BEGe detectors from isotopic enrichment to diode production and testing. As demonstrated all steps were carefully planned in order to minimize the exposure of the enriched germanium to cosmic radiation. Following this premise, acceptance and characterisation measurement of the newly produced diodes have been performed within the HEROICA project in the Belgian underground laboratory HADES close to the diode manufacturer. The test program and the results from a subset of the recently terminated GERDA Phase II BEGe survey will be presented.

  1. Toxicity of Fatty Acid autoxidation products: highest anti-microbial toxicity in the initial oxidative phase.

    PubMed

    Matikainen, Jorma; Lehtinen, Markku; Pelttari, Eila; Elo, Hannu

    2015-01-01

    The autoxidation-degradation processes of polyunsaturated fatty acids give rise to toxic products, and the relative toxicity at different stages of the process is of great interest. We report here that when methyl α-linolenate is exposed to sunlight and air, its antimicrobial activity against yeasts and bacteria (as measured by agar diffusion) reaches its maximum during the early oxidative phase when addition of oxygen occurs and the mass increases drastically. Before exposure, the activity is minimal or zero, but it increases rapidly during the first days of the test, simultaneously with the increase of the mass of the material, and begins to decrease while the mass is still increasing and before the mass begins to decrease due to degradation and formation of volatile compounds. Thus, the products formed during the degradation phase of the process are far less toxic to the test organisms than the compounds formed at the early stages when addition of oxygen occurs with maximal rate. PMID:25546619

  2. Kinetic and Product Yields of the Gas-Phase Reactions of Isoprene Hydroperoxides with Atmospheric Oxidants

    NASA Astrophysics Data System (ADS)

    Kumar, V.; Lozano, E. I.; Maitra, S.; Manning, D. M.; Cervantes, R.; Hasson, A. S.

    2015-12-01

    Isoprene is a volatile organic compound (VOC) that is emitted into the atmosphere by plants and trees. It has the largest emission rate of any non-methane VOC and is very reactive, and therefore has a major impact on the chemical composition of the atmosphere. Isoprene Hydroperoxides (IHP) are formed in the atmosphere from the chemical degradation of isoprene. These compounds can then potentially react in the atmosphere with atmospheric oxidants (ozone, OH, NO3) to produce secondary products. This chemistry is potentially important as it may contribute to particle growth and to mediation of ozone concentrations. In this work, the kinetics and mechanisms of the reactions of two IHPs with ozone were investigated. IHPs were synthesized and purified, and were characterized by NMR and HPLC. The gas phase chemistry of these compounds was then studied in chamber experiments using PTRMS as the primary analytical tool. The rate coefficients for reaction with ozone were measured at room temperature and 1 atmosphere using the relative rate technique, and yields of major gas phase reaction products were measured. Implications of these results will be discussed.

  3. A study of the phase composition of the slag from ferrotitanium production

    SciTech Connect

    Donets, I.G.; Kir'yakova, I.E.; Parkhomenko, N.M.

    1985-07-01

    Today, in accordance with the plan for Soviet economic and social development, attention is being paid to the development of no-waste and low-waste technologies for the treatment of mineral raw materials and, in particular, to the problems of utilizing the waste from the metallurgical industry. From this point of view there is significant interest in the treatment of slag from ferrotitanium production whose output from the Novolipetsk Metallurgical Combine alone is many thousands of tons per year. This paper reports some results of a study of the phase composition of these slags using petrographic and x-ray phase methods with the aim of establishing possible ways of treating and utilizing these slags. The chemical composition (%) of the slags is as follows: SiO/sub 2/, 0/08-1.6; CaO, 10-17; Al/sub 2/O/sub 3/, 62-75; MgO, 1.0-3.5; FeO, 0.1-2.5; and TiO/sub 2/, 15-21. The data on the chemical composition are averaged for single types of slags from ferrotitanium production at the Aktyubinsk and Kuznets Ferro-Alloy Plants and the Novolipetsk Metallurgical Combine.

  4. TEC Fluctuations Map - pilot phase of the new IGS Ionospheric Product

    NASA Astrophysics Data System (ADS)

    Sieradzki, Rafal; Krankowski, Andrzej

    2013-04-01

    Since 1998 Ionospheric Working Group of the International GNSS Service has been creating the reliable global VTEC maps. Currently the ionospheric maps are generated with 2 hour time resolution and show the mean state of the Total Electron Content for this period.They cannot demonstrate the whole dynamic of the electron concentration especially during the storm-time periods for the equatorial region and at high latitudes. However, in the last few years the number of the permanent GNSS station around North Geomagnetic Pole increased systematically and nowadays it is possible to create the map of ionospheric variability for this region. Importance of this topic has turned up in the latest IGS Ionosphere Working Group resolution passed during the International GNSS Service Workshop 2012. At the beginning 2013 the IGS is planning to start the pilot phase of the new ionospheric product - TEC Fluctuations map, which are generated at GRL/UWM Center in Olsztyn. The maps are created based on phase observations from over 150 permanent GNSS stations belong to IGS/EPN, PBO and POLENET Networks located over 45th degree of the north geomagnetic latitude. In order to estimate the level of the ionospheric variability ROT Index is used. The presentation shows the applied algorithm, the example maps for different ionospheric conditions and plans. In the future other IGS Ionosphere Associate Analysis Centers will also create maps of ionospheric variability for routine generation IGS combined product.

  5. Coral–algal phase shifts alter fish communities and reduce fisheries production

    PubMed Central

    Ainsworth, Cameron H; Mumby, Peter J

    2015-01-01

    Anthropogenic stress has been shown to reduce coral coverage in ecosystems all over the world. A phase shift towards an algae-dominated system may accompany coral loss. In this case, the composition of the reef-associated fish assemblage will change and human communities relying on reef fisheries for income and food security may be negatively impacted. We present a case study based on the Raja Ampat Archipelago in Eastern Indonesia. Using a dynamic food web model, we simulate the loss of coral reefs with accompanied transition towards an algae-dominated state and quantify the likely change in fish populations and fisheries productivity. One set of simulations represents extreme scenarios, including 100% loss of coral. In this experiment, ecosystem changes are driven by coral loss itself and a degree of habitat dependency by reef fish is assumed. An alternative simulation is presented without assumed habitat dependency, where changes to the ecosystem are driven by historical observations of reef fish communities when coral is lost. The coral–algal phase shift results in reduced biodiversity and ecosystem maturity. Relative increases in the biomass of small-bodied fish species mean higher productivity on reefs overall, but much reduced landings of traditionally targeted species. PMID:24953835

  6. Coral-algal phase shifts alter fish communities and reduce fisheries production.

    PubMed

    Ainsworth, Cameron H; Mumby, Peter J

    2015-01-01

    Anthropogenic stress has been shown to reduce coral coverage in ecosystems all over the world. A phase shift towards an algae-dominated system may accompany coral loss. In this case, the composition of the reef-associated fish assemblage will change and human communities relying on reef fisheries for income and food security may be negatively impacted. We present a case study based on the Raja Ampat Archipelago in Eastern Indonesia. Using a dynamic food web model, we simulate the loss of coral reefs with accompanied transition towards an algae-dominated state and quantify the likely change in fish populations and fisheries productivity. One set of simulations represents extreme scenarios, including 100% loss of coral. In this experiment, ecosystem changes are driven by coral loss itself and a degree of habitat dependency by reef fish is assumed. An alternative simulation is presented without assumed habitat dependency, where changes to the ecosystem are driven by historical observations of reef fish communities when coral is lost. The coral-algal phase shift results in reduced biodiversity and ecosystem maturity. Relative increases in the biomass of small-bodied fish species mean higher productivity on reefs overall, but much reduced landings of traditionally targeted species. PMID:24953835

  7. Production of ethanol from refinery waste gases. Phase 2, technology development, annual report

    SciTech Connect

    Arora, D.; Basu, R.; Phillips, J.R.; Wikstrom, C.V.; Clausen, E.C.; Gaddy, J.L.

    1995-07-01

    Oil refineries discharge large volumes of H{sub 2}, CO, and CO{sub 2} from cracking, coking, and hydrotreating operations. This program seeks to develop a biological process for converting these waste gases into ethanol, which can be blended with gasoline to reduce emissions. Production of ethanol from all 194 US refineries would save 450 billion BTU annually, would reduce crude oil imports by 110 million barrels/year and emissions by 19 million tons/year. Phase II efforts has yielded at least 3 cultures (Clostridium ljungdahlii, Isolate O-52, Isolate C-01) which are able to produce commercially viable concentrations of ethanol from CO, CO{sub 2}, and H{sub 2} in petroleum waste gas. Single continuous stirred tank reactor studies have shown that 15-20 g/L of ethanol can be produced, with less than 5 g/L acetic acid byproduct. Culture and reactor optimization in Phase III should yield even higher ethanol concentrations and minimal acetic acid. Product recovery studies showed that ethanol is best recovered in a multi-step process involving solvent extraction/distillation to azeotrope/azeotropic distillation or pervaporation, or direct distillation to the azeotrope/azeotropic distillation or pervaporation. Projections show that the ethanol facility for a typical refinery would require an investment of about $30 million, which would be returned in less than 2 years.

  8. GERDA phase II detectors: Behind the production and characterisation at low background conditions

    SciTech Connect

    Maneschg, Werner; Collaboration: GERDA Collaboration; and others

    2013-08-08

    The low background GERmanium Detector Array (GERDA) at Laboratori Nazionali del Gran Sasso (LNGS) is designed to search for the rare neutrinoless double beta decay (0νββ) in {sup 76}Ge. Bare germanium diodes are operated in liquid argon which is used as coolant, as passive and soon active as well shield against external radiation. Currently, Phase I of the experiment is running using ∼15 kg of co-axial High Purity Germanium diodes. In order to increase the sensitivity of the experiment 30 Broad Energy Germanium (BEGe) diodes will be added within 2013. This presentation reviews the production chain of the new BEGe detectors from isotopic enrichment to diode production and testing. As demonstrated all steps were carefully planned in order to minimize the exposure of the enriched germanium to cosmic radiation. Following this premise, acceptance and characterisation measurement of the newly produced diodes have been performed within the HEROICA project in the Belgian underground laboratory HADES close to the diode manufacturer. The test program and the results from a subset of the recently terminated GERDA Phase II BEGe survey will be presented.

  9. [Determination of main degradation products of lignin using reversed-phase high performance liquid chromatography].

    PubMed

    Jiang, Zhijing; Zhu, Junjun; Li, Xin; Lian, Zhina; Yu, Shiyuan; Yong, Qiang

    2011-01-01

    An analytical method using reversed-phase high performance liquid chromatography (RP-HPLC) was developed for the separation and quantitative determination of main degradation products of lignin (4-hydroxybenzoic acid, vanillic acid, syringic acid, 4-hydroxybenzaldehyde, vanillin and syringaldehyde) during the steam exploded pretreatment for corn stovers. The separation was carried out on a C18 column with the mobile phase of acetonitrile-water (containing 1.5% acetic acid) at 30 degrees C at a flow rate of 0.8 mL/min and the detection wavelengths of 254 and 280 nm. Under the optimized conditions, the correlation coefficients of the 6 compounds were between 0.999 9 and 1.000 0. The recoveries of the 6 compounds were all above 96% and the relative standard deviations (n = 6) were less than 2.5%. This method is suitable for the determination of the main degradation products of lignin during the steam exploded pretreatment of lignocellulosics. PMID:21574401

  10. Phase space matching and finite lifetime effects for top-pair production close to threshold

    SciTech Connect

    Hoang, Andre H.; Reisser, Christoph J.; Ruiz-Femenia, Pedro

    2010-07-01

    The top-pair tt production cross section close to threshold in e{sup +}e{sup -} collisions is strongly affected by the small lifetime of the top quark. Since the cross section is defined through final states containing the top decay products, a consistent definition of the cross section depends on prescriptions of how these final states are accounted for the cross section. Experimentally, these prescriptions are implemented, for example, through cuts on kinematic quantities such as the reconstructed top quark invariant masses. As long as these cuts do not reject final states that can arise from the decay of a top and an antitop quark with a small off-shellness compatible with the nonrelativistic power counting, they can be implemented through imaginary phase space matching conditions in nonrelativistic QCD. The prescription-dependent cross section can then be determined from the optical theorem using the e{sup +}e{sup -} forward scattering amplitude. We compute the phase space matching conditions associated to cuts on the top and antitop invariant masses at next-to-next-to-leading logarithmic order and partially at next-to-next-to-next-to-leading logarithmic order in the nonrelativistic expansion accounting also for higher order QCD effects. Together with finite lifetime and electroweak effects known from previous work, we analyze their numerical impact on the tt cross section. We show that the phase space matching contributions are essential to make reliable nonrelativistic QCD predictions, particularly for energies below the peak region, where the cross section is small. We find that irreducible background contributions associated to final states that do not come from top decays are strongly suppressed and can be neglected for the theoretical predictions.

  11. A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1

    SciTech Connect

    Overbey, W.K. Jr.; Reeves, T.K.; Salamy, S.P.; Locke, C.D.; Johnson, H.R.; Brunk, R.; Hawkins, L. )

    1991-05-01

    This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The research has been conducted by Beckley College, Inc. (Beckley) and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center. Phase 1 of the project consisted of compiling and analyzing relevant geological and gas production information in selected areas of Raleigh County, West Virginia, ultimately narrowed to the Eccles, West Virginia, 7 {1/2} minute Quadrangle. The Phase 1 analysis identified key parameters contributing to the accumulation and production of natural gas in Raleigh County, developed analog models relating geological factors to gas production, and identified specific sites to test and verify the analysis methodologies by drilling. Based on the Phase 1 analysis, five sites have been identified with high potential for economic gas production. Phase 2 will consist of drilling, completing, and producing one or more wells at the sites identified in the Phase 1 analyses. The initial well is schedules to the drilled in April 1991. This report summarizes the results of the Phase 1 investigations. For clarity, the report has been prepared in two volumes. Volume 1 presents the Phase 1 overview; Volume 2 contains the detailed geological and production information collected and analyzed for this study.

  12. Phase analysis in single-chain variable fragment production by recombinant Pichia pastoris based on proteomics combined with multivariate statistics.

    PubMed

    Fujiki, Yuya; Kumada, Yoichi; Kishimoto, Michimasa

    2015-08-01

    The proteomics technique, which consists of two-dimensional gel electrophoresis (2-DE), peptide mass fingerprinting (PMF), gel image analysis, and multivariate statistics, was applied to the phase analysis of a fed-batch culture for the production of a single-chain variable fragment (scFv) of an anti-C-reactive protein (CRP) antibody by Pichia pastoris. The time courses of the fed-batch culture were separated into three distinct phases: the growth phase of the batch process, the growth phase of the fed-batch process, and the production phase of the fed-batch process. Multivariate statistical analysis using 2-DE gel image analysis data clearly showed the change in the culture phase and provided information concerning the protein expression, which suggested a metabolic change related to cell growth and production during the fed-batch culture. Furthermore, specific proteins, such as alcohol oxidase, which is strongly related to scFv expression, and proteinase A, which could biodegrade scFv in the latter phases of production, were identified via the PMF method. The proteomics technique provided valuable information about the effect of the methanol concentration on scFv production. PMID:25636980

  13. Products from the reaction of monoterpenes with ozone and their distribution between the gas- and particle-phase

    NASA Astrophysics Data System (ADS)

    Winterhalter, R.; Römpp, A.; Kavouras, I. G.; Moortgat, G. K.

    2003-04-01

    The monoterpene-ozone reaction is an important source of tropospheric aerosols, yet the formation mechanism and physico-chemical properties of the organic aerosol particles are not well understood. In this paper a detailed product study of the gas-phase ozonolysis of various monoterpenes (alpha-pinene, beta-pinene, sabinene, limonene, and 3-carene) is presented, with special focus on the distribution of the products between the gas- and aerosol phase. The reactions were performed in a 570 l glass reactor at 730 Torr and room temperature in synthetic air in the presence and absence of cyclohexane as OH-radical scavenger. The reaction was monitored by FTIR-spectroscopy (ozone, monoterpenes and gas-phase products) and by a Scanning Mobility Particle Sizer (Size distribution, aerosol volume and number concentration). The separation of gas-phase and particulate products was achieved by a combination of gas-phase denuder and filter sampling. Particles were collected with quartz fiber filter coated with 1M NaOH and additionally with teflon filters, while gaseous products were sampled with a diffusion denuder coated with 1M NaOH. The reaction products have been extracted with water, and the extracts have been analysed by LC-MS-MS-TOF using ESI (-) and APCI (+) ionisation. Furthermore the samples have been also analysed by GC-MS after derivatization of the organic acids. The products and their gas-particle partitioning will be presented, and the possible reaction mechanisms will be discussed.

  14. Effect of biochar addition on hydrogen and methane production in two-phase anaerobic digestion of aqueous carbohydrates food waste.

    PubMed

    Sunyoto, Nimas M S; Zhu, Mingming; Zhang, Zhezi; Zhang, Dongke

    2016-11-01

    Effect of biochar addition on hydrogen and methane production in two-phase anaerobic digestion of aqueous carbohydrates was studied using bench-scale bioreactors. The cultures with biochar additions were placed in 100ml reactors and incubated at 35°C and pH 5 for hydrogen production. The residual cultures were then used for methane production, incubated at 35°C and pH 7. Daily yields of hydrogen and methane and weekly yield of volatile fatty acids (VFA) were measured. The hydrogen and methane production potentials, rate and lag phases of the two phases were analysed using the Gompertz model. The results showed that biochar addition increased the maximum production rates of hydrogen by 32.5% and methane 41.6%, improved hydrogen yield by 31.0% and methane 10.0%, and shortened the lag phases in the two phases by 36.0% and 41.0%, respectively. Biochar addition also enhanced VFA generation during hydrogen production and VFA degradation in methane production. PMID:27474855

  15. Enhancement of butanol production in Clostridium acetobutylicum SE25 through accelerating phase shift by different phases pH regulation from cassava flour.

    PubMed

    Li, Han-guang; Zhang, Qing-hua; Yu, Xiao-bin; Wei, Luo; Wang, Qiang

    2016-02-01

    A prominent delay with 12h was encountered in the phase shift from acidogenesis to solventogenesis in butanol production when the substrate-glucose was replaced by cassava flour. To solve this problem, different phase of pH regulation strategies were performed to shorten this delay time. With this effort, the phase shift occurred smoothly and the fermentation time was shortened. Under the optimal conditions, 16.24g/L butanol and 72h fermentation time were achieved, which were 25.3% higher and 14.3% shorter than those in the case of without pH regulation. Additionally, the effect of CaCO3 on "acid crash" and butanol production was also investigated. It was found that organic acids reassimilation would be of benefit to enhance butanol production. These results indicated that the simple but effective approach for acceleration of phase shift is a promising technique for shortening the fermentation time and improvement of butanol production. PMID:26642220

  16. Mineralogical composition and phase-to-phase relationships in natural hydraulic lime and/or natural cement - raw materials and burnt products revealed by scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Kozlovcev, Petr; Přikryl, Richard; Racek, Martin; Přikrylová, Jiřina

    2016-04-01

    In contrast to modern process of production of cement clinker, traditional burning of natural hydraulic lime below sintering temperature relied on the formation of new phases from ion migration between neighbouring mineral grains composing raw material. The importance of the mineralogical composition and spatial distribution of rock-forming minerals in impure limestones used as a raw material for natural hydraulic lime presents not well explored issue in the scientific literature. To fill this gap, the recent study focuses in detailed analysis of experimentally burnt impure limestones (mostly from Barrandian area, Bohemian Massif). The phase changes were documented by optical microscopy, X-ray diffraction, and scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS) coupled with x-ray elemental mapping. The latest allowed for visualization of distribution of elements within raw materials and burnt products. SEM/EDS study brought valuable data on the presence of transitional and/or minor phases, which were poorly detectable by other methods.

  17. Bioethanol production from raffinate phase of supercritical CO2 extracted Stevia rebaudiana leaves.

    PubMed

    Coban, Isik; Sargin, Sayit; Celiktas, Melih Soner; Yesil-Celiktas, Ozlem

    2012-09-01

    The extracts of Stevia rebaudiana are marketed as dietary supplements and utilized as natural sweetening agent in food products. Subsequent to extraction on industrial scale, large quantities of solid wastes are produced. The aim of this study was to investigate the bioconversion efficiency of supercritical CO(2) extracted S. rebaudiana residues. Therefore, leaves were extracted with supercritical CO(2) and ethanol mixture in order to obtain glycosides, then the raffinate phase was hydrolyzed by both dilute acid and various concentrations of cellulase and β-glucosidase cocktail. The maximum yield of reducing sugars reached 25.67 g/L under the optimal conditions of enzyme pretreatment, whereas 32.00 g/L was reached by consecutive enzymatic and acid hydrolyses. Bioethanol yield (20 g/L, 2.0% inoculum, 2 days) based on the sugar consumed was 45.55% corresponding to a productivity of 0.19 kg/m(3)h which demonstrates challenges to be utilized as a potential feedstock for the production of bioethanol. PMID:22784953

  18. Novel two-phase upflow digestion of wet-carbonized peat product water

    SciTech Connect

    Sajjad, A.; Henry, M.P.; Srivastava, V.J.; Mensinger, J.

    1987-01-01

    This paper presents the development and operating results of a novel two-phase upflow anaerobic digestion process for the conversion of organic matter present in the process effluent generated during the wet-carbonization processing of peat. It exhibited a methane yield of 3.0 SCF/lb chemical oxygen demand (COD) added during thermophilic (55/degree/C) digestion at a short hydraulic retention time of (HRT) 3 days. This yield represents approximately 90% of the ultimate methane yield for this process effluent. About 80% of the feed biological oxygen demand (BOD) and 65% of COD was converted during the anaerobic digestion process. This innovative process has a substantive beneficial impact on the production of net energy and availability of surplus digester methane for conversion to other energy forms such as hot water or low-pressure steam for in-process use. 12 refs., 6 figs., 7 tabs.

  19. Production of phloroglucinol by Escherichia coli using a stationary-phase promoter.

    PubMed

    Cao, Yujin; Xian, Mo

    2011-09-01

    Escherichia coli was metabolically engineered using a new host-vector system to produce phloroglucinol. The key biosynthetic gene phlD (encoding a type III polyketide synthase) from Pseudomonas fluorescens was expressed in E. coli using the stationary-phase promoter of the fic gene and a high-copy plasmid. In shake-flasks, the engineered strain produced phloroglucinol up to 0.28 g/l with a productivity of 0.014 g/l h. About 9.2% of the glucose consumed was converted to phloroglucinol after 20 h. Compared with the widely used inducible T7 promoter system, this strain did not require IPTG induction and the final titer of phloroglucinol was 22% higher. PMID:21544607

  20. NOAA GCOM-W1/AMSR2 Oceanic Environmental Products: Phase-2

    NASA Astrophysics Data System (ADS)

    Jelenak, Z.; Alsweiss, S.; Chang, P.; Park, J. Y.

    2014-12-01

    Passive microwave radiometry is a special application of microwave communications technology for the purpose of collecting Earth's electromagnetic radiation. With the use of radiometers onboard earth orbiting satellites, scientists are able to monitor the Earth's environment and climate system on both short- and long-term temporal scales with near global coverage. The Global Change Observation Mission (GCOM) is part of the Japanese Aerospace Exploration Agency (JAXA) broader commitment toward global and long-term observation of the Earth's environment. GCOM consists of two polar orbiting satellite series, GCOM-W (Water) and GCOM-C (Climate), with 1-year overlap between them for inter-calibration. AMSR2 onboard GCOM-W1 is a microwave radiometer system that measures dual polarized radiances at 6.9, 7.3, 10.65, 18.7, 23.8, 36.5, and 89.0 GHz. It is a sun-synchronous orbiter that acquires microwave radiances by conically scanning the Earth's surface at a nominal earth incidence angle of 55 degrees that results in a wide swath of 1450 km. As a part of Joint Polar Satellite System (JPSS) program the National Oceanic and Atmospheric Administration (NOAA) GCOM-W1 product development and validation project will provide NOAA's users access to critical geophysical products derived from AMSR-2. These products, which are detailed in NOAA's JPSS Level 1 Requirements Document Supplement, include: microwave brightness temperature, total precipitable water, cloud liquid water, precipitation type/rate, sea surface temperature, and Sea Surface Wind Speed. Phase-1 of the AMSR-2 project at NOAA included inter-calibration of AMSR-2 measured brightness temperatures with the Tropical Rainfall Measuring Mission Microwave Imager as the reference radiometer. The second phase of the project utilized the calibrated brightness temperatures in a robust Bayesian network to retrieve more accurate geophysical parameters over the ocean surface. It can handle retrievals even with missing channels and

  1. Hydrogen production through aqueous-phase reforming of ethylene glycol in a washcoated microchannel.

    PubMed

    D'Angelo, M Fernanda Neira; Ordomsky, Vitaly; Paunovic, Violeta; van der Schaaf, John; Schouten, Jaap C; Nijhuis, T Alexander

    2013-09-01

    Aqueous-phase reforming (APR) of biocarbohydrates is conducted in a catalytically stable washcoated microreactor where multiphase hydrogen removal enhances hydrogen efficiency. Single microchannel experiments are conducted following a simplified model based on the microreactor concept. A coating method to deposit a Pt-based catalyst on the microchannel walls is selected and optimized. APR reactivity tests are performed by using ethylene glycol as the model compound. Optimum results are achieved with a static washcoating technique; a highly uniform and well adhered 5 μm layer is deposited on the walls of a 320 μm internal diameter (ID) microchannel in one single step. During APR of ethylene glycol, the catalyst layer exhibits high stability over 10 days after limited initial deactivation. The microchannel presents higher conversion and selectivity to hydrogen than a fixed-bed reactor. The benefits of using a microreactor for APR can be further enhanced by utilizing increased Pt loadings, higher reaction temperatures, and larger carbohydrates (e.g., glucose). The use of microtechnology for aqueous-phase reforming will allow for a great reduction in the reformer size, thus rendering it promising for distributed hydrogen production. PMID:23592593

  2. Contralateral acoustic stimulation alters the magnitude and phase of distortion product otoacoustic emissions

    PubMed Central

    Deeter, Ryan; Abel, Rebekah; Calandruccio, Lauren; Dhar, Sumitrajit

    2009-01-01

    Activation of medial olivocochlear efferents through contralateral acoustic stimulation (CAS) has been shown to modulate distortion product otoacoustic emission (DPOAE) level in various ways (enhancement, reduction, or no change). The goal of this study was to investigate the effect of a range of CAS levels on DPOAE fine structure. The 2f1-f2 DPOAE was recorded (f2∕f1=1.22, L1=55 dB, and L2=40 dB) from eight normal-hearing subjects, using both a frequency-sweep paradigm and a fixed frequency paradigm. Contamination due to the middle ear muscle reflex was avoided by monitoring the magnitude and phase of a probe in the test ear and by monitoring DPOAE stimulus levels throughout testing. Results show modulations in both level and frequency of DPOAE fine structure patterns. Frequency shifts observed at DPOAE level minima could explain reports of enhancement in DPOAE level due to efferent activation. CAS affected the magnitude and phase of the DPOAE component from the characteristic frequency region to a greater extent than the component from the overlap region between the stimulus tones. This differential effect explains the occasional enhancement observed in DPOAE level as well as the frequency shift in fine structure patterns. PMID:19894823

  3. Comparison of transient and distortion-product otoacoustic emissions during the luteal and follicular phases of the menstrual cycle.

    PubMed

    Gurbuzler, Levent; Yelken, Kursat; Aladag, Ibrahim; Eyibilen, Ahmet; Koc, Sema

    2012-08-01

    We conducted a study to examine cochlear activity in women with a naturally occurring menstrual cycle by measuring transient otoacoustic emissions (TOAEs) and distortion-product otoacoustic emissions (DPOAEs). Our study population was made up of 11 women aged 20 to 40 years (mean: 35.6) who were not taking a contraceptive medication or hormone therapy. Measurements of TOAEs and DPOAEs were made during both the follicular phase and the luteal phase of the menstrual cycle. We found no statistically significant difference in any of the TOAE amplitude values between the two phases. Although a sharp decrease at the 0.75 kHz frequency was seen in DPOAEs during both phases, none of the amplitude values in the tested frequencies were significantly different between the two phases. The absence of TOAE and DPOAE amplitude changes suggests that it is unnecessary to take into account the phase of the menstrual cycle when interpreting the results of otoacoustic emissions testing. PMID:22930081

  4. A novel anaerobic two-phase system for biohydrogen production and in situ extraction of organic acid byproducts.

    PubMed

    Sarma, Saurabh Jyoti; Brar, Satinder Kaur; Le Bihan, Yann; Buelna, Gerardo

    2015-06-01

    Owing to CO2-free emission, hydrogen is considered as a potential green alternative of fossil fuels. Water is the major emission of hydrogen combustion process and gravimetric energy density of hydrogen is nearly three times more than that of gasoline and diesel fuel. Biological hydrogen production, therefore, has commercial significance; especially, when it is produced from low-cost industrial waste-based feedstock. Light independent anaerobic fermentation is simple and mostly studied method of biohydrogen production. During hydrogen production by this method, a range of organic acid byproducts are produced. Accumulation of these byproducts is inhibitory for hydrogen production as it may result in process termination due to sharp decrease in medium pH or by possible metabolic shift. For the first time, therefore, a two-phase anaerobic bioreactor system has been reported for biohydrogen production which involves in situ extraction of different organic acids. Among different solvents, based on biocompatibility oleyl alcohol has been chosen as the organic phase of the two-phase system. An organic:aqueous phase ratio of 1:50 has been found to be optimum for hydrogen production. The strategy was capable of increasing the hydrogen production from 1.48 to 11.65 mmol/L-medium. PMID:25575763

  5. Products of the gas-phase reactions of O{sub 3} with alkenes

    SciTech Connect

    Atkinson, R.; Tuazon, E.C.; Aschmann, S.M.

    1995-12-01

    Selected products of the gas-phase reactions of a series of alkenes (1-pentene, 1-hexene, 1-heptene, 1-octene, 2,3-dimethyl-l-butene, cyclopentene and 1-methylcyclohexene) with O{sub 3} have been identified and quantified by gas chromatography and in situ Fourier transform infrared absorption spectroscopy. Because OH radicals are formed in these O{sub 3} reactions, experiments were carried out in the presence of sufficient cyclohexane or n-octane to scavenge > 90 % of the OH radicals formed. OH radical formation yields from the O{sub 3}-alkene reactions were derived from the amounts of cyclohexanone and cyclohexanol formed in O{sub 3}-alkene-cyclohexane-air mixtures. The molar yields of the carbonyls products R{sub 1}C(O)R{sub 2} plus HCHO from the O{sub 3} reactions with the five 1-alkenes (R{sub 1}R{sub 2}C=CH{sub 2}) studied were 1.1 {plus_minus} 0.1, as expected from the presently accepted reaction mechanism.

  6. Entanglement and quantum phase transitions in matrix-product spin-1 chains

    SciTech Connect

    Alipour, S.; Karimipour, V.; Memarzadeh, L.

    2007-05-15

    We consider a one-parameter family of matrix-product states of spin-1 particles on a periodic chain and study in detail the entanglement properties of such a state. In particular, we calculate exactly the entanglement of one site with the rest of the chain, and the entanglement of two distant sites with each other, and show that the derivative of both these properties diverge when the parameter g of the states passes through a critical point. Such a point can be called a point of quantum phase transition, since at this point the character of the matrix-product state, which is the ground state of a Hamiltonian, changes discontinuously. We also study the finite size effects and show how the entanglement depends on the size of the chain. This later part is relevant to the field of quantum computation where the problem of initial state preparation in finite arrays of qubits or qutrits is important. It is also shown that the entanglement of two sites have scaling behavior near the critical point.

  7. Influence of product phase separation on phospholipase A(2) hydrolysis of supported phospholipid bilayers studied by force microscopy.

    PubMed Central

    Nielsen, Lars K; Balashev, Konstatin; Callisen, Thomas H; Bjørnholm, Thomas

    2002-01-01

    In situ atomic force microscopy studies reveal a marked influence of the initial presence of hydrolysis products on the hydrolysis of supported phospholipid bilayers by phospholipase A(2). By analysis of the nano-scale topography of a number of supported bilayers with different initial product concentrations, made by Langmuir-Blodgett deposition, we show that small depressions enriched in products are efficiently promoting enzyme degradation of the bilayer. These small depressions, which are indicative of phase separation, are initially present in samples with 75% products. The kinetics of phospholipase A(2) exhibit under certain conditions an initial phase of slow hydrolysis, termed the latency phase, followed by a marked increase in the hydrolysis rate. The appearance of the phase-separated bilayer is strikingly similar to that of bilayers at the end of the latency phase. By analysis of individual nano-scale defects we illustrate a quantitative difference in the growth rates of defects caused by product aggregation and other structural defects. This difference shows for the first time how the enzyme prefers one type of defect to another. PMID:12414695

  8. Partition of actinides and fission products between metal and molten salt phases: Theory, measurement, and application to IFR pyroprocess development

    SciTech Connect

    Ackerman, J.P.; Johnson, T.R.

    1993-10-01

    The chemical basis of Integral Fast Reactor fuel reprocessing (pyroprocessing) is partition of fuel, cladding, and fission product elements between molten LiCl-KCl and either a solid metal phase or a liquid cadmium phase. The partition reactions are described herein, and the thermodynamic basis for predicting distributions of actinides and fission products in the pyroprocess is discussed. The critical role of metal-phase activity coefficients, especially those of rare earth and the transuranic elements, is described. Measured separation factors, which are analogous to equilibrium constants but which involve concentrations rather than activities, are presented. The uses of thermodynamic calculations in process development are described, as are computer codes developed for calculating material flows and phase compositions in pyroprocessing.

  9. Variations in short term products of inorganic carbon fixation in exponential and stationary phase cultures of Aphanocapsa 6308.

    PubMed

    Weathers, P J; Allen, M M

    1978-03-01

    Aphanocapsa 6308 metabolizes both NaHCO3 and Na2CO3. The short term incorporation (5-s) metabolic pattern and the patterns of incorporation of bicarbonate for exponential versus stationary phase cultures differ, however. Cells were equilibrated for 10 min in air and distilled water prior to injection of either NaH14CO3 at pH 8.0, or Na214CO3 at pH 11.0. Hot ethanol extracts were analyzed via paper chromatography and autoradiography for products of CO2 fixation. At 5 s, malate (51.5%) predominates slightly as a primary bicarbonate fixation product over 3-phosphoglycerate (40.3%); 3-phosphoglycerate is the primary product of carbonate fixation. At 60 s, the carbonate and bicarbonate labelling patterns are similar. Cells in stationary phase fix in 5 s a greater proportion of bicarbonate into malate (36% vs. 14% for 3-phosphoglycerate) than do cells in exponential growth. Likewise, 60 s incorporations show a large amount of bicarbonate fixed into aspartate (30.9%) in stationary phase cells over that of exponential phase (11.6%). These data suggest an operative C4 pathway for purposes not related to carbohydrate synthesis but rather as compensation for the incomplete tricarboxylic acid cycle in cyanobacteria. The enhancement of both aspartate fixation and CO2 fixation into citrulline in stationary phase correlates with an increase in cyanophycin granule production which requires both aspartate and arginine. PMID:417691

  10. Direct observation of single stationary-phase bacteria reveals a surprisingly long period of constant protein production activity

    PubMed Central

    Gefen, Orit; Fridman, Ofer; Ronin, Irine; Balaban, Nathalie Q.

    2014-01-01

    Exponentially growing bacteria are rarely found in the wild, as microorganisms tend to spend most of their lifetime at stationary phase. Despite this general prevalence of stationary-phase bacteria, they are as yet poorly characterized. Our goal was to quantitatively study this phase by direct observation of single bacteria as they enter into stationary phase and by monitoring their activity over several days during growth arrest. For this purpose, we devised an experimental procedure for starving single Escherichia coli bacteria in microfluidic devices and measured their activity by monitoring the production rate of fluorescent proteins. When amino acids were the sole carbon source, the production rate decreased by an order of magnitude upon entry into stationary phase. We found that, even while growth-arrested, bacteria continued to produce proteins at a surprisingly constant rate over several days. Our identification of this newly observed period of constant activity in nongrowing cells, designated as constant activity stationary phase, makes possible the conduction of assays that require constant protein expression over time, and are therefore difficult to perform under exponential growth conditions. Moreover, we show that exogenous protein expression bears no fitness cost on the regrowth of the population when starvation ends. Further characterization of constant activity stationary phase—a phase where nongrowing bacteria can be quantitatively studied over several days in a reproducible manner—should contribute to a better understanding of this ubiquitous but overlooked physiological state of bacteria in nature. PMID:24344288

  11. Ethanol production via fungal decomposition and fermentation of biomass. Phase II (FY 1981) annual progress report

    SciTech Connect

    Antonopoulos, A. A.; Wene, E. G.

    1981-10-01

    This program has as its main goal the isolation and development of Fusarium strains that can efficiently and economically decompose plant polysaccharides to pentoses and hexoses and ferment them to ethanol for fuel purposes. During Phase II (FY 1981) of this program, more than 800 new Fusarium isolates were isolated and screened. All showed cellulolytic activity. The Fusarium mutant ANL 3-72181 (derived after uv exposure of ANL 22 isolate) produced 2.45 iu cellulase after 14 days. This cellulase activity was achieved in the presence of 0.7 mg/mL extracellular protein. In separate tests, the use of both proteose peptone and yeast extract with 1% cellulose increased the production of extracellular protein three times over that on cellulose alone. Initial fermentation by Fusarium strains on 1% glucose produced up to 4.2 mg/mL ethanol in 48 hours. All Fusarium isolates and mutants found during this period were screened for xylose fermentation. Ethanol production during early experimentation required from 120 to 144 hours to yield 4.0 to 4.5 mg/mL ethanol from 1% xylose solutions. Through continuous selection of isolates, this time was reduced to 66 hours. By recycling Fusarium cell mass, fermentations of 1% xylose yielded 4.0 to 4.3 mg/mL ethanol in 48 hours. Consecutive fermentations of 2% xylose produced an average of 8.1 mg/mL ethanol in 48 hours. Fermentation of a 4.5% xylose + 2% glucose solution produced 21 mg/mL ethanol and 0.8 mg/mL acetic acid, while fermentation of a 7% xylose + 2% glucose solution yielded 25.5 mg/mL ethanol and 0.85 mg/mL acetic acid; these fermentations were aerated at a rate of 0.03 v/v-min.

  12. Gas-phase transfer of polymer cross-linking agents and by-products to solid oral pharmaceuticals.

    PubMed

    Maus, Russell G; Li, Min; Clement, Christopher M; Kinzer, Jeffery A

    2007-11-01

    In the pharmaceutical industry, solid oral compressed tablets (OCT) are frequently transported in bulk containers prior to packaging. While in this state, the product is generally protected from interaction with liquid and solid contaminants by physical barriers (e.g., polyethylene bags, drums, etc.). Vapor phase contamination, although generally less frequently observed, is possible. A specific example of the detection and identification of volatile by-products (acetophenone and 2-phenyl-2-propanol) of a common polymer cross-linking agent (dicumyl peroxide) is presented. The product tablets were compressed, placed into double polyethylene bags, and subsequently placed into a polyethylene drum for shipment overseas. To cushion the product during transit, a cross-linked polyethylene foam disk (designed to fit into the bottom of the drum) was placed below the bag of tablets. Initially, these contaminants were detected by HPLC with UV detection at the receiving laboratory, and assumed to be degradates of the active components of the product. Further analysis showed that neither the collected UV absorbance data nor the observed levels of the contaminants were consistent with known degradates of the product. Liquid extraction followed by GC-MS analysis of the product as well as the cross-linked foam disk exhibited measurable quantities of the contaminants in question. Vapor phase transfer of these cross-linking agent by-products, originating in the cross-linked foam pads, was determined to be the root cause for the presence of these compounds in the product. PMID:17686599

  13. Single-step gas-phase polyperfluoroalkylation of naphthalene leads to thermodynamic products.

    PubMed

    San, Long K; Bukovsky, Eric V; Kuvychko, Igor V; Popov, Alexey A; Strauss, Steven H; Boltalina, Olga V

    2014-04-01

    High-temperature gas-phase, solvent- and catalyst-free reaction of naphthalene with an excess of RF I reagent (RF CF3 , C2 F5 , n-C3 F7 , and n-C4 F9 ) was used for the first time to produce a series of highly perfluoroalkylated naphthalene products NAPH(RF )n with n=2-5. Four 95+ % pure 1,3,5,7-NAPH(RF )4 with RF CF3 , C2 F5 , n-C3 F7 , and n-C4 F9 were isolated using a simple chromatography-free procedure. These new compounds were fully characterized by (19) F and (1) H NMR spectroscopy, X-ray crystallography (for RF CF3 and C2 F5 ), atmospheric-pressure chemical ionization mass spectrometry, and cyclic and square-wave voltammetry. DFT calculations confirm that the proposed synthesis yields the most stable isomers that have not been accessed by alternative preparation techniques. PMID:24591166

  14. High-yield production of graphene by liquid-phase exfoliation of graphite

    NASA Astrophysics Data System (ADS)

    Hernandez, Yenny; Nicolosi, Valeria; Lotya, Mustafa; Blighe, Fiona M.; Sun, Zhenyu; de, Sukanta; McGovern, I. T.; Holland, Brendan; Byrne, Michele; Gun'ko, Yurii K.; Boland, John J.; Niraj, Peter; Duesberg, Georg; Krishnamurthy, Satheesh; Goodhue, Robbie; Hutchison, John; Scardaci, Vittorio; Ferrari, Andrea C.; Coleman, Jonathan N.

    2008-09-01

    Fully exploiting the properties of graphene will require a method for the mass production of this remarkable material. Two main routes are possible: large-scale growth or large-scale exfoliation. Here, we demonstrate graphene dispersions with concentrations up to ~0.01 mg ml-1, produced by dispersion and exfoliation of graphite in organic solvents such as N-methyl-pyrrolidone. This is possible because the energy required to exfoliate graphene is balanced by the solvent-graphene interaction for solvents whose surface energies match that of graphene. We confirm the presence of individual graphene sheets by Raman spectroscopy, transmission electron microscopy and electron diffraction. Our method results in a monolayer yield of ~1 wt%, which could potentially be improved to 7-12 wt% with further processing. The absence of defects or oxides is confirmed by X-ray photoelectron, infrared and Raman spectroscopies. We are able to produce semi-transparent conducting films and conducting composites. Solution processing of graphene opens up a range of potential large-area applications, from device and sensor fabrication to liquid-phase chemistry.

  15. Specific growth rate observer for the growing phase of a Polyhydroxybutyrate production process.

    PubMed

    Jamilis, Martín; Garelli, Fabricio; Mozumder, Md Salatul Islam; Volcke, Eveline; De Battista, Hernán

    2015-03-01

    This paper focuses on the specific growth rate estimation problem in a Polyhydroxybutyrate bioplastic production process by industrial fermentation. The kinetics of the process are unknown and there are uncertainties in the model parameters and inputs. During the first hours of the growth phase of the process, biomass concentration can be measured online by an optical density sensor, but as cell density increases this method becomes ineffective and biomass measurement is lost. An asymptotic observer is developed to estimate the growth rate for the case without biomass measurement based on corrections made by a pH control loop. Furthermore, an exponential observer based on the biomass measurement is developed to estimate the growth rate during the first hours, which gives the initial condition to the asymptotic observer. Error bounds and robustness to uncertainties in the models and in the inputs are found. The estimation is independent of the kinetic models of the microorganism. The characteristic features of the observer are illustrated by numerical simulations and validated by experimental results. PMID:25307471

  16. Kinetics, Mechanism, and Secondary Organic Aerosol Yield of Aqueous Phase Photo-oxidation of α-Pinene Oxidation Products.

    PubMed

    Aljawhary, Dana; Zhao, Ran; Lee, Alex K Y; Wang, Chen; Abbatt, Jonathan P D

    2016-03-10

    Formation of secondary organic aerosol (SOA) involves atmospheric oxidation of volatile organic compounds (VOCs), the majority of which are emitted from biogenic sources. Oxidation can occur not only in the gas-phase but also in atmospheric aqueous phases such as cloudwater and aerosol liquid water. This study explores for the first time the aqueous-phase OH oxidation chemistry of oxidation products of α-pinene, a major biogenic VOC species emitted to the atmosphere. The kinetics, reaction mechanisms, and formation of SOA compounds in the aqueous phase of two model compounds, cis-pinonic acid (PIN) and tricarballylic acid (TCA), were investigated in the laboratory; TCA was used as a surrogate for 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), a known α-pinene oxidation product. Aerosol time-of-flight chemical ionization mass spectrometry (Aerosol-ToF-CIMS) was used to follow the kinetics and reaction mechanisms at the molecular level. Room-temperature second-order rate constants of PIN and TCA were determined to be 3.3 (±0.5) × 10(9) and 3.1 (±0.2) × 10(8) M(-1) s(-1), respectively, from which were estimated their condensed-phase atmospheric lifetimes. Aerosol-ToF-CIMS detected a large number of products leading to detailed reaction mechanisms for PIN and MBTCA. By monitoring the particle size distribution after drying, the amount of SOA material remaining in the particle phase was determined. An aqueous SOA yield of 40 to 60% was determined for PIN OH oxidation. Although recent laboratory studies have focused primarily on aqueous-phase processing of isoprene-related compounds, we demonstrate that aqueous formation of SOA materials also occurs from monoterpene oxidation products, thus representing an additional source of biogenically driven aerosol formation. PMID:26299576

  17. Identification of unwanted photoproducts of cosmetic preservatives in personal care products under ultraviolet-light using solid-phase microextraction and micro-matrix solid-phase dispersion.

    PubMed

    Alvarez-Rivera, Gerardo; Llompart, Maria; Garcia-Jares, Carmen; Lores, Marta

    2015-04-17

    The photochemical transformation of widely used cosmetic preservatives including benzoates, parabens, BHA, BHT and triclosan has been investigated in this work applying an innovative double-approach strategy: identification of transformation products in aqueous photodegradation experiments (UV-light, 254nm), followed by targeted screening analysis of such photoproducts in UV-irradiated cosmetic samples. Solid-phase microextraction (SPME) was applied, using different fiber coatings, in order to widen the range of detectable photoproducts in water, whereas UV-irradiated personal care products (PCPs) containing the target preservatives were extracted by micro-matrix solid-phase dispersion (micro-MSPD). Both SPME and micro-MSPD-based methodologies were successfully optimized and validated. Degradation kinetics of parent species, and photoformation of their transformation by-products were monitored by gas chromatography coupled to mass spectrometry (GC-MS). Thirty nine photoproducts were detected in aqueous photodegradation experiments, being tentatively identified based on their mass spectra. Transformation pathways between structurally related by-products, consistent with their kinetic behavior were postulated. The photoformation of unexpected photoproducts such as 2- and 4-hydroxybenzophenones, and 2,8-dichlorodibenzo-p-dioxin in PCPs are reported in this work for the first time. PMID:25757820

  18. Chemical characterization of the main secondary organic aerosol (SOA) products formed through aqueous-phase photonitration of guaiacol

    NASA Astrophysics Data System (ADS)

    Kitanovski, Z.; Čusak, A.; Grgić, I.; Claeys, M.

    2014-04-01

    Guaiacol (2-methoxyphenol) and its derivatives can be emitted into the atmosphere by thermal degradation (i.e. burning) of wood lignins. Due to its volatility, guaiacol is predominantly distributed in the atmospheric gaseous phase. Recent studies have shown the importance of aqueous-phase reactions in addition to the dominant gas-phase and heterogeneous reactions of guaiacol, in the formation of secondary organic aerosol (SOA) in the atmosphere. The main objectives of the present study were to chemically characterize the low-volatility SOA products of the aqueous-phase photonitration of guaiacol and examine their possible presence in urban atmospheric aerosols. The aqueous-phase reactions were carried out under simulated sunlight and in the presence of H2O2 and nitrite. The formed guaiacol reaction products were concentrated by using solid-phase extraction (SPE) and then purified by means of semi-preparative high-performance liquid chromatography (HPLC). The fractionated individual compounds were isolated as pure solids and further analyzed with liquid-state 1H, 13C and 2D nuclear magnetic resonance (NMR) spectroscopy and direct infusion negative ion electrospray ionization tandem mass spectrometry ((-)ESI-MS/MS). The NMR and product ion (MS2) spectra were used for unambiguous product structure elucidation. The main products of guaiacol photonitration are 4-nitroguaiacol (4NG), 6-nitroguaiacol (6NG), and 4,6-dinitroguaiacol (4,6DNG). Using the isolated compounds as standards, 4NG and 4,6DNG were unambiguously identified in winter PM10 aerosols from the city of Ljubljana (Slovenia) by means of HPLC/(-)ESI-MS/MS. Owing to the strong absorption of UV and visible light, 4,6DNG could be an important constituent of atmospheric "brown" carbon, especially in regions affected by biomass burning.

  19. Energy Efficient Aluminum Production - Pilot-Scale Cell Tests - Final Report for Phase I and Phase II

    SciTech Connect

    R. A. Christini

    1999-12-30

    A cermet anode that produces oxygen and a cathode material that is wetted by aluminum can provide a dimensionally stable inter-electrode distance in the Hall-Heroult cell. This can be used to greatly improve the energy and/or productivity efficiencies. The concept, which was developed and tested, uses a system of vertically interleaved anodes and cathodes. The major advantage of this concept is the significant increase in electrochemical surface area compared to a horizontal orientation of anode and cathode that is presently used in the Hall-Heroult process. This creates an additional advantage for energy reduction of 1.3 kWh/lb or a 20% productivity improvement. The voltages obtained in an optimized cell test met the energy objectives of the project for at least two weeks. An acceptable current efficiency was never proven, however, during either pilot scale or bench scale tests with the vertical plate configuration. This must be done before a vertical cell can be considered viab le. Anode corrosion rate must be reduced by at least a factor of three in order to produce commercial purity aluminum. It is recommended that extensive theoretical and bench scale investigations be done to improve anode materials and to demonstrate acceptable current efficiencies in a vertical plate cell before pilot scale work is continued.

  20. The gas chromatographic analysis of the reaction products of the partial isobutane oxidation as a two phase process.

    PubMed

    Willms, Thomas; Kryk, Holger; Hampel, Uwe

    2016-08-01

    The partial oxidation of isobutane to t-butyl hydroperoxide (TBHP) has been studied analytically for the first time as a two-phase process in a capillary micro reactor. In order to obtain detailed information on products, yields, selectivities and reaction pathways, the products have been investigated by GC/MS. An Rxi-5ms column and a PTV-injector have been used to analyze the liquid products. TBHP, di-t-butyl peroxide (DTBP), t-butanol (TBA), and propanone as main products as well as further by-products e.g. methanal, isopropanol, isobutanol and isobutanal in minor quantities have been identified by MS. The liquid products have been obtained by quenching the reaction and vaporizing the isobutane afterwards by pressure reduction using a mass flow controller allowing a constant mass flow. For all liquid reaction products calibrations, a validation of the method including limits of quantification and detection as well as calculation of uncertainties has been performed. The results have been applied successfully for the investigation of the selectivities of the main products (TBHP, DTBP, TBA, propanone) of the isobutane oxidation. In the frame of the analytical investigation of this reaction a correlation coefficient of r(2)>0.999 for TBHP and DTBP, which is necessary to perform a validation, has been obtained for the first time. The gaseous phase has been analyzed using a GASPRO column, a DEANS switch, a mole sieve column and a TCD detector. Apart from the gaseous reactants, isobutene has been found. PMID:27378248

  1. Mixing in a three-phase system: Enhanced production of oil-wet reservoirs by CO2 injection

    NASA Astrophysics Data System (ADS)

    Jiménez-Martínez, Joaquín.; Porter, Mark L.; Hyman, Jeffrey D.; Carey, J. William; Viswanathan, Hari S.

    2016-01-01

    We recreate three-phase reservoir conditions (high-pressure/temperature) using a microfluidics system and show that the use of scCO2 for restimulation operations, such as hydraulic fracturing, can enhance mixing and production. The results inform hydrocarbon extraction from deep shale formations, which has recently generated an energy boom that has lowered hydrocarbon costs. However, production decreases rapidly and methods to increase efficiency or allow restimulation of wells are needed. In our experiments, the presence of residual brine from initial production creates spatiotemporal variability in the system that causes the injected scCO2 to more effectively interact-mix with trapped hydrocarbon, thereby increasing recovery. We apply volume-averaging techniques to upscale brine saturation, which allows us to analyze the complex three-phase system in the framework of well characterized two-phase systems. The upscaled three-phase system behaves like a two-phase system: greater mixing with larger non-wetting content and higher heterogeneity. The results are contrary to previous observations in water-wet systems.

  2. Supplementation of Lactobacillus acidophilus fermentation product can attenuate the acute phase response following a lipopolysaccharide challenge in pigs.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to determine if feeding a Lactobacillus acidophilus fermentation product to weaned pigs would reduce stress and acute phase responses (APR) following a lipopolysaccharide (LPS) challenge. Pigs (n=30; 6.4±0.1 kilograms body weight) were housed individually in pens with ad libi...

  3. Land application uses for dry FGD by-products. Phase 1, [Annual report], December 1, 1991--November 30, 1992

    SciTech Connect

    Bigham, J.; Dick, W.; Forster, L.; Hitzhusen, F.; McCoy, E.; Stehouwer, R.; Traina, S.; Wolfe, W.; Haefner, R.

    1993-04-01

    The 1990 amendments to the Clean Air Act have spurred the development of flue gas desulfurization (FGD) processes, several of which produce a dry, solid by-product material consisting of excess sorbent, reaction products containing sulfates and sulfites, and coal fly ash. Presently FGD by-product materials are treated as solid wastes and must be landfilled. However, landfill sites are becoming more scarce and tipping fees are constantly increasing. It is, therefore, highly desirable to find beneficial reuses for these materials provided the environmental impacts are minimal and socially acceptable. Phase 1 results of a 4 and 1/2 year study to demonstrate large volume beneficial uses of FGD by-products are reported. The purpose of the Phase 1 portion of the project was to characterize the chemical, physical, mineralogical and engineering properties of the FGD by-product materials obtained from various FGD technologies being developed in the state of Ohio. Phase 1 also involved the collection of baseline economic data related to the beneficial reuse of these FGD materials. A total of 58 samples were collected and analyzed. In summary Phase 1 results revealed that FGD by-product materials are essentially coal fly ash materials diluted with unreacted sorbent and reaction products. High volume beneficial reuses will depend on the economics of their substituting for existing materials for various types of applications (e.g. as an agricultural liming material, soil borrow for highway embankment construction, and reclamation of active and abandoned surface coal mines). Environmental constraints to the beneficial reuse of dry FGD byproduct materials, based on laboratory and leachate studies, seem to be less than for coal fly ash.

  4. Insights into gas-phase reaction mechanisms of small carbon radicals using isomer-resolved product detection.

    PubMed

    Trevitt, Adam J; Goulay, Fabien

    2016-02-17

    For reactive gas-phase environments, including combustion, extraterrestrials atmospheres and our Earth's atmosphere, the availability of quality chemical data is essential for predictive chemical models. These data include reaction rate coefficients and product branching fractions. This perspective overviews recent isomer-resolved production detection experiments for reactions of two of the most reactive gas phase radicals, the CN and CH radicals, with a suite of small hydrocarbons. A particular focus is given to flow-tube experiments using synchrotron photoionization mass spectrometry. Coupled with computational studies and other experiment techniques, flow tube isomer-resolved product detection have provided significant mechanistic details of these radical + neutral reactions with some general patterns emerging. PMID:26841339

  5. The Phase Behavior Effect on the Reaction Engineering of Transesterification Reactions and Reactor Design for Continuous Biodiesel Production

    NASA Astrophysics Data System (ADS)

    Csernica, Stephen N.

    transitions from two phases to a single phase, or pseudo-single phase. The transition to a single phase or pseudo-single phase is a function of the methanol content. Regardless, the maximum observed reaction rate occurs at the point of the phase transition, when the concentration of triglycerides in the methanol phase is largest. The phase transition occurs due to the accumulation of the primary product, biodiesel methyl esters. Through various experiments, it was determined that the rate of the triglyceride mass transfer into the methanol phase, as well as the solubility of triglycerides in methanol, increases with increasing methyl ester concentration. Thus, there exists some critical methyl ester concentration which favors the formation of a single or pseudo-single phase system. The effect of the by-product glycerol on the reaction kinetics was also investigated. It was determined that at low methanol to triglyceride molar ratios, glycerol acts to inhibit the reaction rate and limit the overall triglyceride conversion. This occurs because glycerol accumulates in the methanol phase, i.e. the primary reaction volume. When glycerol is at relatively high concentrations within the methanol phase, triglycerides become excluded from the reaction volume. This greatly reduces the reaction rate and limits the overall conversion. As the concentration of methanol is increased, glycerol becomes diluted and the inhibitory effects become dampened. Assuming pseudo-homogeneous phase behavior, a simple kinetic model incorporating the inhibitory effects of glycerol was proposed based on batch reactor data. The kinetic model was primarily used to theoretically compare the performance of different types of continuous flow reactors for continuous biodiesel production. It was determined that the inhibitory effects of glycerol result in the requirement of very large reactor volumes when using continuous stirred tank reactors (CSTR). The reactor volume can be greatly reduced using tubular style

  6. Neddylation is required for herpes simplex virus type I (HSV-1)-induced early phase interferon-beta production.

    PubMed

    Zhang, Xueying; Ye, Zhenjie; Pei, Yujun; Qiu, Guihua; Wang, Qingyang; Xu, Yunlu; Shen, Beifen; Zhang, Jiyan

    2016-09-01

    Type I interferons such as interferon-beta (IFN-β) play essential roles in the host innate immune response to herpes simplex virus type I (HSV-1) infection. The transcription of type I interferon genes is controlled by nuclear factor-κB (NF-κB) and interferon regulatory factor (IRF) family members including IRF3. NF-κB activation depends on the phosphorylation of inhibitor of κB (IκB), which triggers its ubiqitination and degradation. It has been reported that neddylation inhibition by a pharmacological agent MLN4924 potently suppresses lipopolysaccharide (LPS)-induced proinflammatory cytokine production with the accumulation of phosphorylated IκBα. However, the role of neddylation in type I interferon expression remains unknown. Here, we report that neddylation inhibition with MLN4924 or upon UBA3 deficiency led to accumulation of phosphorylated IκBα, impaired IκBα degradation, and impaired NF-κB nuclear translocation in the early phase of HSV-1 infection even though phosphorylation and nuclear translocation of IRF3 were not affected. The blockade of NF-κB nuclear translocation by neddylation inhibition becomes less efficient at the later time points of HSV-1 infection. Consequently, HSV-1-induced early phase IFN-β production significantly decreased upon MLN4924 treatment and UBA3 deficiency. NF-κB inhibitor JSH-23 mimicked the effects of neddylation inhibition in the early phase of HSV-1 infection. Moreover, the effects of neddylation inhibition on HSV-1-induced early phase IFN-β production diminished in the presence of NF-κB inhibitor JSH-23. Thus, neddylation contributes to HSV-1-induced early phase IFN-β production through, at least partially, promoting NF-κB activation. PMID:27593482

  7. Modeling and estimation of production rate for the production phase of non-growth-associated high cell density processes.

    PubMed

    Jamilis, Martín; Garelli, Fabricio; Mozumder, Md Salatul Islam; Castañeda, Teresita; De Battista, Hernán

    2015-10-01

    This paper addresses the estimation of the specific production rate of intracellular products and the modeling of the bioreactor volume dynamics in high cell density fed-batch reactors. In particular, a new model for the bioreactor volume is proposed, suitable to be used in high cell density cultures where large amounts of intracellular products are stored. Based on the proposed volume model, two forms of a high-order sliding mode observer are proposed. Each form corresponds to the cases with residual biomass concentration or volume measurement, respectively. The observers achieve finite time convergence and robustness to process uncertainties as the kinetic model is not required. Stability proofs for the proposed observer are given. The observer algorithm is assessed numerically and experimentally. PMID:26149912

  8. Occurrence assessment for disinfectants and disinfection by-products (phase 6A) in public drinking water. Final report

    SciTech Connect

    Not Available

    1992-08-03

    The EPA Office of Ground Water and Drinking Water is developing national primary drinking water regulations for disinfectant and disinfection by-product contaminants. Thirteen contaminants are being considered to be regulated under Phase 6. These contaminants, referred to as Phase 6a, are the subject of the report. The information is important for setting the Maximum Contaminant Level Goal for a contaminant. The exposure information also is used to estimate the baseline health impact assessment of current levels and for evaluation of the health benefits of the regulatory alternatives.

  9. NATO CCMS PILOT STUDY: CLEAN PRODUCTS AND PROCESSES - PHASE I: AN ASSESSMENT

    EPA Science Inventory

    Clean Products and Processes - promote cooperation for improving the common pollution landscape by stimulating cross-national dialogues and collaboration. Share knowledge on the methods, tools, and technologies for making cleaner products and processes possible.

  10. Exploring the Possible Role That Solid Phase LNAPL Biodegradation End Products Have on Electrical Biogeophysical Signatures

    NASA Astrophysics Data System (ADS)

    Samuel, A. L.; McGuffy, C.; Slater, L. D.; Bekins, B. A.; Herkelrath, W. N.; Ntarlagiannis, D.; Atekwana, E. A.

    2013-12-01

    Prior biogeophysical research at sites contaminated by Light Non Aqueous Phase Liquid (LNAPL) has attributed electrical conductivity anomalies in the smear zone to increases in pore fluid specific conductance driven by the production of inorganic acids and associated mineral dissolution. However, data to support this interpretation are lacking and research at the Bemidji site suggests an alternative interpretation. Ongoing research at the National Crude Oil Spill Fate and Natural Attenuation Research Site in Bemidji, MN, provides an opportunity to study the biogeophysical signatures of a mature hydrocarbon spill with a unique supporting inventory of geochemical and hydrological data. Previous biogeophysical research at this site identified a strong magnetic susceptibility (MS) signal in the smear zone, primarily due to the presence of magnetite, which is presumably driven by biotic iron reduction processes associated with long-term natural attenuation. We hypothesize that it is possible that the conductivity enhancement previously observed at hydrocarbon sites is, at least in part driven by precipitation of metallic minerals in the smear zone. This process could also explain recently reported induced polarization anomalies observed in the smear zone at other sites. In order to test our hypothesis, a dense array of electrodes spanning a 5 m interval was installed in boreholes at two locations: [1] centered on the smear zone at a contaminated location (where oil pooling is known to be thickest); [2] centered on the water table at an uncontaminated location for control. We constructed arrays composed of 66 electrodes spaced between 7.5 and 10 cm apart in order to examine fine-scale resistivity and induced polarization structure of the smear zone. Electrical measurements were acquired using a Wenner-type configuration with multiple unit electrode spacings. Results from these arrays were compared with MS and magnetite concentration data from both borehole logs and cores

  11. Gas phase emissions from cooking processes and their secondary aerosol production potential

    NASA Astrophysics Data System (ADS)

    Klein, Felix; Platt, Stephen; Bruns, Emily; Termime-roussel, Brice; Detournay, Anais; Mohr, Claudia; Crippa, Monica; Slowik, Jay; Marchand, Nicolas; Baltensperger, Urs; Prevot, Andre; El Haddad, Imad

    2014-05-01

    -ToF-MS) were used to quantify OA and VOC emissions, respectively. SOA production potential of the different emissions was quantified by introducing them into the PSI mobile smog chamber and a potential aerosol chamber (PAM) where they were photochemically aged. The measurements of primary emissions suggest that the COA factor identified in ambient atmospheric aerosols is mostly related to fat release from frying with vegetable oils or grilling fatty-meats. In contrast, vegetable cooking (boiling and frying) was associated with significant VOC emissions. The VOC emissions from frying consist mainly of aldehydes which are formed through breaking of fatty acids. Gas phase composition, emission factors and SAPP from all these processes will be presented. This work was supported by the Swiss National Science Foundation as well as the Swiss Federal Office for the Environment. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n.° 290605 (COFUND: PSI-FELLOW). J. Allan et al, Atmos. Chem. Phys. 10, 647-668 (2010) X.-F. Huang et al, Atmos. Chem. Phys. 10, 8933-8945 (2010) Y.-L. Sun et al, Atmos. Chem. Phys. 11, 1581-1602 (2011)

  12. Subpicosecond electron bunch train production using a phase-space exchange technique

    SciTech Connect

    Sun, Y.-E.; Piot, P.; Johnson, A.S.; Lumpkin, A.H.; Maxwell, T.J.; Ruan, J.; Thurman-Keup, R.M.; /Fermilab

    2011-03-01

    Our recent experimental demonstration of a photoinjector electron bunch train with sub-picosecond structures is reported in this paper. The experiment is accomplished by converting an initially horizontal beam intensity modulation into a longitudinal phase space modulation, via a beamline capable of exchanging phase-space coordinates between the horizontal and longitudinal degrees of freedom. The initial transverse modulation is produced by intercepting the beam with a multislit mask prior to the exchange. We also compare our experimental results with numerical simulations.

  13. Methane production improvement by modulation of solid phase immersion in dry batch anaerobic digestion process: Dynamic of methanogen populations.

    PubMed

    André, L; Ndiaye, M; Pernier, M; Lespinard, O; Pauss, A; Lamy, E; Ribeiro, T

    2016-05-01

    Several 60L dry batch anaerobic digestion (AD) reactors were implemented with or without liquid reserve on cattle manure. The immersed part modulation of cattle manure increased the methane flow of about 13%. The quantitative real time PCR and the optimized DNA extraction were implemented and validated to characterize and quantify the methanogen dynamic in dry batch AD process. Final quantities of methanogens converged toward the same level in several inocula at the end of AD. Methanogen dynamic was shown by dominance of Methanosarcinaceae for acetotrophic methanogens and Methanobacteriales for the hydrogenotrophic methanogens. Overall, methanogens populations were stabilized in liquid phase, except Methanosaetaceae. Solid phase was colonized by Methanomicrobiales and Methanosarcinaceae populations giving a support to biofilm development. The methane increase could be explained by a raise of Methanosarcinaceae population in presence of a total contact between solid and liquid phases. Methanosarcinaceae was a bio-indicator of the methane production. PMID:26897414

  14. Selective enrichment of the degradation products of organophosphorus nerve agents by zirconia based solid-phase extraction.

    PubMed

    Kanaujia, Pankaj K; Pardasani, Deepak; Tak, Vijay; Purohit, Ajay K; Dubey, D K

    2011-09-23

    Selective extraction and enrichment of nerve agent degradation products has been achieved using zirconia based commercial solid-phase extraction cartridges. Target analytes were O-alkyl alkylphosphonic acids and alkylphosphonic acids, the environmental markers of nerve agents such as sarin, soman and VX. Critical extraction parameters such as modifier concentration, nature and volume of washing and eluting solvents were investigated. Amongst other anionic compounds, selectivity in extraction was observed for organophosphorus compounds. Recoveries of analytes were determined by GC-MS which ranged from 80% to 115%. Comparison of zirconia based solid-phase extraction method with anion-exchange solid-phase extraction revealed its selectivity towards phosphonic acids. The limits of detection (LOD) and limit of quantification (LOQ) with selected analytes were achieved down to 4.3 and 8.5 ng mL(-1), respectively, in selected ion monitoring mode. PMID:21862029

  15. Noncoding RNA. piRNA-guided transposon cleavage initiates Zucchini-dependent, phased piRNA production.

    PubMed

    Han, Bo W; Wang, Wei; Li, Chengjian; Weng, Zhiping; Zamore, Phillip D

    2015-05-15

    PIWI-interacting RNAs (piRNAs) protect the animal germ line by silencing transposons. Primary piRNAs, generated from transcripts of genomic transposon "junkyards" (piRNA clusters), are amplified by the "ping-pong" pathway, yielding secondary piRNAs. We report that secondary piRNAs, bound to the PIWI protein Ago3, can initiate primary piRNA production from cleaved transposon RNAs. The first ~26 nucleotides (nt) of each cleaved RNA becomes a secondary piRNA, but the subsequent ~26 nt become the first in a series of phased primary piRNAs that bind Piwi, allowing piRNAs to spread beyond the site of RNA cleavage. The ping-pong pathway increases only the abundance of piRNAs, whereas production of phased primary piRNAs from cleaved transposon RNAs adds sequence diversity to the piRNA pool, allowing adaptation to changes in transposon sequence. PMID:25977554

  16. Production and associated economics of fingerling to stocker to growout modular phases for farming channel catfish, Ictalurus punctatus, in commercial size ponds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 2-year study was conducted to evaluate fingerling to stocker (phase 2) and stocker to growout (phase 3) of three phases of a modular production system for channel catfish in commercial-scale ponds. Fingerlings (mean = 14.3 kg/1000, 11.9 cm) were stocked into each of six earthen ponds (1.62 ha) at ...

  17. Production of biohydrogen by aqueous phase reforming of polyols over platinum catalysts supported on three-dimensionally bimodal mesoporous carbon.

    PubMed

    Park, Hyun Ju; Kim, Ho-Dong; Kim, Tae-Wan; Jeong, Kwang-Eun; Chae, Ho-Jeong; Jeong, Soon-Yong; Chung, Young-Min; Park, Young-Kwon; Kim, Chul-Ung

    2012-04-01

    Now in 3D! Three-dimensionally bimodal carbons (3D-BMC) with mesopores of tunable size (controlled through the polymerization of the carbon precursor) are synthesized. After loading with platinum, the catalysts are used in aqueous phase reforming of polyols, and show superior performance in terms of carbon conversion, hydrogen yield, selectivity, and hydrogen production rate compared to platinum catalysts supported on activated carbon or two-dimensional CMK-3. PMID:22415941

  18. Reactive uptake of ozone by proxies for organic aerosols: Surface-bound and gas-phase products

    NASA Astrophysics Data System (ADS)

    Thomas, Elan R.; Frost, Gregory J.; Rudich, Yinon

    2001-02-01

    Gas-phase and surface-bound products were determined for the reaction of ozone with self assembled monolayers of alkanes and terminal alkenes serving as proxies for atmospheric organic aerosols. The organic surfaces were characterized using infrared (IR) spectroscopy (direct absorption and attenuated total reflection) as well as contact angle measurements with water before and after the reaction with ozone. The contact angle of the organic surfaces was reduced by ˜20° owing to the reaction. Following the reaction, IR absorption due to the presence of carbonyls and carboxylic acids was observed on the surface. Gas-phase products were determined using infrared spectroscopy immediately above the reaction surface. Under dry conditions, gas-phase formaldehyde yields of 0.5±0.1 for organic monolayers of allyltrichlorosilane (C3=) and octenyltrichlorosilane (C8=) terminal alkenes were observed, in good agreement with the yields observed for gas phase ozonolysis of terminal alkenes. Surfaces of n-octane (C8) as well as processed alkene surfaces were nonreactive toward ozone. The reaction mechanism of ozone with the surface alkenes is discussed. Finally, the possible implications for the chemistry of organic aerosols are discussed and studied using a box model and realistic atmospheric scenarios.

  19. Production method of carbamazepine/saccharin cocrystal particles by using two solution mixing based on the ternary phase diagram

    NASA Astrophysics Data System (ADS)

    Kudo, Shoji; Takiyama, Hiroshi

    2014-04-01

    In the pharmaceutical field, improvement of drug solubility is required, and an interest in cocrystals is growing. Crystallization methods for industrial production of cocrystals have not been developed enough whereas many cocrystals have been prepared in order to find a new crystal form by screening in the laboratory. The objective of this study was the development of the crystallization method which is useful for the industrial production of cocrystal particles based on the phase diagram. A cocrystal of carbamazepine and saccharin was selected as a model substance. The ternary phase diagram of carbamazepine and saccharin in methanol at 303 K was measured. A cocrystallization method of mixing two kinds of different eutectic solutions was designed based on the ternary phase diagram. In order to adjust the cocrystallization conditions, the determination method of the driving force for cocrystal deposition such as supersaturation based on mass balance was proposed. The cocrystal particles were obtained under all the conditions of the five mixing ratios. From these experimental results, the relationship between the supersaturation and the induction time for nucleation was confirmed as well as conventional crystallization. In conclusion, the crystallization method for industrial production of cocrystal particles including the determination of the supersaturation was suggested.

  20. Unlocking the potential of supported liquid phase catalysts with supercritical fluids: low temperature continuous flow catalysis with integrated product separation

    PubMed Central

    Franciò, Giancarlo; Hintermair, Ulrich; Leitner, Walter

    2015-01-01

    Solution-phase catalysis using molecular transition metal complexes is an extremely powerful tool for chemical synthesis and a key technology for sustainable manufacturing. However, as the reaction complexity and thermal sensitivity of the catalytic system increase, engineering challenges associated with product separation and catalyst recovery can override the value of the product. This persistent downstream issue often renders industrial exploitation of homogeneous catalysis uneconomical despite impressive batch performance of the catalyst. In this regard, continuous-flow systems that allow steady-state homogeneous turnover in a stationary liquid phase while at the same time effecting integrated product separation at mild process temperatures represent a particularly attractive scenario. While continuous-flow processing is a standard procedure for large volume manufacturing, capitalizing on its potential in the realm of the molecular complexity of organic synthesis is still an emerging area that requires innovative solutions. Here we highlight some recent developments which have succeeded in realizing such systems by the combination of near- and supercritical fluids with homogeneous catalysts in supported liquid phases. The cases discussed exemplify how all three levels of continuous-flow homogeneous catalysis (catalyst system, separation strategy, process scheme) must be matched to locate viable process conditions. PMID:26574523

  1. Unlocking the potential of supported liquid phase catalysts with supercritical fluids: low temperature continuous flow catalysis with integrated product separation.

    PubMed

    Franciò, Giancarlo; Hintermair, Ulrich; Leitner, Walter

    2015-12-28

    Solution-phase catalysis using molecular transition metal complexes is an extremely powerful tool for chemical synthesis and a key technology for sustainable manufacturing. However, as the reaction complexity and thermal sensitivity of the catalytic system increase, engineering challenges associated with product separation and catalyst recovery can override the value of the product. This persistent downstream issue often renders industrial exploitation of homogeneous catalysis uneconomical despite impressive batch performance of the catalyst. In this regard, continuous-flow systems that allow steady-state homogeneous turnover in a stationary liquid phase while at the same time effecting integrated product separation at mild process temperatures represent a particularly attractive scenario. While continuous-flow processing is a standard procedure for large volume manufacturing, capitalizing on its potential in the realm of the molecular complexity of organic synthesis is still an emerging area that requires innovative solutions. Here we highlight some recent developments which have succeeded in realizing such systems by the combination of near- and supercritical fluids with homogeneous catalysts in supported liquid phases. The cases discussed exemplify how all three levels of continuous-flow homogeneous catalysis (catalyst system, separation strategy, process scheme) must be matched to locate viable process conditions. PMID:26574523

  2. The production of hydrogen by dark fermentation of municipal solid wastes and slaughterhouse waste: A two-phase process

    NASA Astrophysics Data System (ADS)

    Gómez, X.; Morán, A.; Cuetos, M. J.; Sánchez, M. E.

    A two-phase fermentation process for the treatment of waste, intended for the recovery of hydrogen for energy use, was investigated in its initial fermentation phase. Hydrogen production was obtained from a mixed culture based on an active mesophilic inoculum without any selective treatment being applied. The liquid stream generated by the hydrogen fermentation process was stabilized in the following, methanogenic, phase for the recovery of methane and further breaking down of the waste stream. The whole process was carried out at a temperature in the mesophilic range (34 °C). The substrate used was an unsterilized mixture of the organic fraction of municipal solid wastes (OFMSW) and slaughterhouse waste from a poultry-processing plant. The hydrogen-producing phase was capable of stable performance under the hydraulic retention times (HRTs) evaluated (3 and 5 days). No methane was detected in the first phase at any point during the whole period of the experiment and the hydrogen yield showed no symptoms of declining as time elapsed. The amount of hydrogen obtained from the fermentation process was in the range of 52.5-71.3 N L kg -1 VS rem.

  3. The photochemical production of organic nitrates from α-pinene and loss via acid-dependent particle phase hydrolysis

    NASA Astrophysics Data System (ADS)

    Rindelaub, Joel D.; McAvey, Kevin M.; Shepson, Paul B.

    2015-01-01

    The hydroxyl radical oxidation of α-pinene under high NOx conditions was studied in a photochemical reaction chamber to investigate organic nitrate (RONO2) production and fate between the gas and particle phases. We report an organic nitrate yield of 26 ± 7% from the oxidation of this monoterpene in the presence of nitric oxide (NO). However, the apparent organic nitrate yield was found to be highly dependent on both chamber relative humidity (RH) and seed aerosol acidity, likely as a result of particle phase hydrolysis. The particle phase loss of organic nitrates is believed to increase the gas to particle partitioning within the system, leading to decreased RONO2 yields in both the gas and particle phases at elevated RH and an apparent non-equilibrium partitioning mechanism. The hydrolysis of particle phase organic nitrates in this study, starting at low chamber relative humidity, implies that aerosol partitioning of organic nitrates may be an important sink for atmospheric NOx and may have a significant impact on regional air quality.

  4. Pre-Launch Phase 1 Calibration and Validation Rehearsal of Geophysical Data Products of Soil Moisture Active Passive (SMAP) Mission

    NASA Astrophysics Data System (ADS)

    Colliander, A.; Jackson, T. J.; Chan, S.; Dunbar, R.; Das, N. N.; Kim, S.; Reichle, R. H.; De Lannoy, G. J.; Liu, Q.; Kimball, J. S.; Yi, Y.; Cosh, M. H.; Bindlish, R.; Crow, W. T.; Dang, L.; Yueh, S. H.; Njoku, E. G.

    2013-12-01

    NASA's Soil Moisture Active Passive (SMAP) Mission is scheduled for launch in October 2014. The objective of the mission is global mapping of soil moisture and freeze/thaw state. SMAP utilizes an L-band radar and radiometer sharing a rotating 6-meter mesh reflector antenna. The instruments will operate onboard the SMAP spacecraft in a 685-km Sun-synchronous near-polar orbit, viewing the surface at a constant 40-degree incidence angle with a 1000-km swath width. Merging of active and passive L-band observations of the mission will enable an unprecedented combination of accuracy, resolution, coverage and revisit-time for soil moisture and freeze/thaw state retrieval. SMAP measurements will enable significantly improved estimates of water, energy and carbon transfers between the land and atmosphere. The SMAP science data product suite of geophysical parameters will include estimates of surface (top 5 cm) and root-zone (down to 1-m depth) soil moisture, net ecosystem exchange, and classification of the frozen/non-frozen state of the landscape. The primary validation reference of the data products will be ground-based measurements. Other remote sensing and model-based products will be used as additional resources. The post-launch timeline of the mission requires that the geophysical data products are validated (with respect to the mission requirements) within 12 months after a 3-month in-orbit check-out phase. SMAP is taking several preparatory steps in order to meet this schedule. One of the main steps consists of running a rehearsal to exercise calibration and validation procedures planned for the Cal/Val Phase. The rehearsal is divided into two stages. Phase 1, which was conducted in June-August 2013, focused on validation methodologies for the geophysical data products. Phase 2, which will be conducted in May-June 2014, includes operational aspects including a fully functioning SMAP Science Data System. (Note that the rehearsals do not include an airborne field

  5. Lyotropic liquid crystalline L3 phase silicated nanoporous monolithic composites and their production

    DOEpatents

    McGrath, Kathryn M.; Dabbs, Daniel M.; Aksay, Ilhan A.; Gruner, Sol M.

    2003-10-28

    A mesoporous ceramic material is provided having a pore size diameter in the range of about 10-100 nanometers produced by templating with a ceramic precursor a lyotropic liquid crystalline L.sub.3 phase consisting of a three-dimensional, random, nonperiodic network packing of a multiple connected continuous membrane. A preferred process for producing the inesoporous ceramic material includes producing a template of a lyotropic liquid crystalline L.sub.3 phase by mixing a surfactant, a co-surfactant and hydrochloric acid, coating the template with an inorganic ceramic precursor by adding to the L.sub.3 phase tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS) and then converting the coated template to a ceramic by removing any remaining liquids.

  6. NATO CCMS PILOT STUDY ON CLEAN PRODUCTS AND PROCESSES -(PHASE I) - 2002 ANNUAL REPORT

    EPA Science Inventory

    The annual report summarizes the activities of the NATO CCMS Pilot Study on clean products and processes for 2002, including the proceedings of the 2002 annual meeting held in Vilnius, Lithuania. The report presents a wealth of information on cleaner production activities in ove...

  7. The Role of Vocational Education in Productivity (Phase I). Final Report.

    ERIC Educational Resources Information Center

    Harrison, Lin; Griggs, Martha

    To determine the role of vocational education in enhancing private sector productivity in the Sedalia, Missouri area, the feasibility of a program to assist business and industry in productivity awareness, assessment, and improvement was evaluated. Based on data from six area business and industry representatives who agreed to complete a survey…

  8. Phase III Advanced Anodes and Cathodes Utilized in Energy Efficient Aluminum Production Cells

    SciTech Connect

    R.A. Christini; R.K. Dawless; S.P. Ray; D.A. Weirauch, Jr.

    2001-11-05

    During Phase I of the present program, Alcoa developed a commercial cell concept that has been estimated to save 30% of the energy required for aluminum smelting. Phase ii involved the construction of a pilot facility and operation of two pilots. Phase iii of the Advanced Anodes and Cathodes Program was aimed at bench experiments to permit the resolution of certain questions to be followed by three pilot cells. All of the milestones related to materials, in particular metal purity, were attained with distinct improvements over work in previous phases of the program. NiO additions to the ceramic phase and Ag additions to the Cu metal phase of the cermet improved corrosion resistance sufficiently that the bench scale pencil anodes met the purity milestones. Some excellent metal purity results have been obtained with anodes of the following composition: Further improvements in anode material composition appear to be dependent on a better understanding of oxide solubilities in molten cryolite. For that reason, work was commissioned with an outside consultant to model the MeO - cryolite systems. That work has led to a better understanding of which oxides can be used to substitute into the NiO-Fe2O3 ceramic phase to stabilize the ferrites and reduce their solubility in molten cryolite. An extensive number of vertical plate bench electrolysis cells were run to try to find conditions where high current efficiencies could be attained. TiB2-G plates were very inconsistent and led to poor wetting and drainage. Pure TiB2 did produce good current efficiencies at small overlaps (shadowing) between the anodes and cathodes. This bench work with vertical plate anodes and cathodes reinforced the importance of good cathode wetting to attain high current efficiencies. Because of those conclusions, new wetting work was commissioned and became a major component of the research during the third year of Phase III. While significant progress was made in several areas, much work needs to be

  9. The Post-Adolescent Phase: A By-Product and a Factor of Development.

    ERIC Educational Resources Information Center

    Planck, Ulrich

    Conducted in 1955 and 1980, random sample interview data of 17 to 28 year-old West Germans from places of less than 5,000 inhabitants are used to support the thesis that the post-adolescent phase has been prolonged in the countryside of West Germany during these years of increasing technical and economic development. Findings indicate occupational…

  10. Mineral phases and metals in baghouse dust from secondary aluminum production

    EPA Science Inventory

    Baghouse dust (BHD) is a solid waste generated by air pollution control systems during secondary aluminum processing (SAP). Management and disposal of BHD can be challenging in the U.S. and elsewhere. In this study, the mineral phases, metal content and metal leachability of 78...

  11. Probing aerosol formation by comprehensive measurements of gas phase oxidation products

    NASA Astrophysics Data System (ADS)

    Ehn, Mikael; Kleist, Einhard; Junninen, Heikki; Sipilä, Mikko; Petäjä, Tuukka; Pullinen, Iida; Springer, Monika; Andres, Stefanie; Rissanen, Matti; Kontkanen, Jenni; Schobesberger, Siegfried; Rubach, Florian; Tillman, Ralf; Lee, Ben H.; Lopez-Hilfiker, Felipe; Kerminen, Veli-Matti; Kulmala, Markku; Worsnop, Douglas R.; Thornton, Joel; Wildt, Jürgen; Mentel, Thomas F.

    2013-05-01

    A comprehensive suite of chemical ionization mass spectrometers (CIMS) were deployed for chamber studies of monoterpene oxidation. The CIMS instruments were able to detect several different groups of compounds ranging from volatile to practically non-volatile. The compound groups showed very different behavior and correlations with aerosol number and mass. Results suggest that major gas phase contributors are not considered in current models.

  12. GAS-PHASE OXIDATION PRODUCTS OF BIPHENYL AND POLYCHLORINATED BIPHENYLS (R825377)

    EPA Science Inventory

    Our laboratory recently measured the gas-phase reaction rate constants of
    polychlorinated biphenyls (PCBs) with the hydroxyl radical (OH) and concluded
    that OH reactions are the primary removal pathway of PCBs from the atmosphere.
    With the reaction system previousl...

  13. THE USE OF RECYCLED SOLID AUTOMOTIVE PAINT WASTES AS INGREDIENTS IN AUTOMOTIVE SEALANT PRODUCTS - PHASE II

    EPA Science Inventory

    About 75,000,000 lbs of paint sludge is generated by the U.S. automotive industry each year. This type of waste and (similar streams from other industries) make significant contributions to landfills. The solution proposed by ASTER, Inc., proven feasible during the Phase I of thi...

  14. A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1

    SciTech Connect

    Overbey, W.K. Jr.; Reeves, T.K.; Salamy, S.P.; Locke, C.D.; Johnson, H.R.; Brunk, R.; Hawkins, L. )

    1991-05-01

    This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The project has been conducted by Beckley College, Inc., and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center (METC). This section, Volume II, contains a detailed discussion of the methodology used and the geological and production information collected and analyzed for this study. A companion document, Volume 1, provides an overview of the program, technique and results of the study. In combination, Volumes I and II cover the completion of the research undertaken under Phase I of this DOE project, which included the identification of five high-potential sites for natural gas production on the Eccles Quadrangle, Raleigh County, West Virginia. Each of these sites was selected for its excellent potential for gas production from both relatively shallow coalbeds and the deeper, conventional reservoir formations.

  15. Reliability prediction for evolutionary product in the conceptual design phase using neural network-based fuzzy synthetic assessment

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Huang, Hong-Zhong; Ling, Dan

    2013-03-01

    Reliability prediction plays an important role in product lifecycle management. It has been used to assess various reliability indices (such as reliability, availability and mean time to failure) before a new product is physically built and/or put into use. In this article, a novel approach is proposed to facilitate reliability prediction for evolutionary products during their early design stages. Due to the lack of sufficient data in the conceptual design phase, reliability prediction is not a straightforward task. Taking account of the information from existing similar products and knowledge from domain experts, a neural network-based fuzzy synthetic assessment (FSA) approach is proposed to predict the reliability indices that a new evolutionary product could achieve. The proposed approach takes advantage of the capability of the back-propagation neural network in terms of constructing highly non-linear functional relationship and combines both the data sets from existing similar products and subjective knowledge from domain experts. It is able to reach a more accurate prediction than the conventional FSA method reported in the literature. The effectiveness and advantages of the proposed method are demonstrated via a case study of the fuel injection pump and a comparative study.

  16. Chemical composition of gas-phase organic carbon emissions from motor vehicles and implications for ozone production.

    PubMed

    Gentner, Drew R; Worton, David R; Isaacman, Gabriel; Davis, Laura C; Dallmann, Timothy R; Wood, Ezra C; Herndon, Scott C; Goldstein, Allen H; Harley, Robert A

    2013-10-15

    Motor vehicles are major sources of gas-phase organic carbon, which includes volatile organic compounds (VOCs) and other compounds with lower vapor pressures. These emissions react in the atmosphere, leading to the formation of ozone and secondary organic aerosol (SOA). With more chemical detail than previous studies, we report emission factors for over 230 compounds from gasoline and diesel vehicles via two methods. First we use speciated measurements of exhaust emissions from on-road vehicles in summer 2010. Second, we use a fuel composition-based approach to quantify uncombusted fuel components in exhaust using the emission factor for total uncombusted fuel in exhaust together with detailed chemical characterization of liquid fuel samples. There is good agreement between the two methods except for products of incomplete combustion, which are not present in uncombusted fuels and comprise 32 ± 2% of gasoline exhaust and 26 ± 1% of diesel exhaust by mass. We calculate and compare ozone production potentials of diesel exhaust, gasoline exhaust, and nontailpipe gasoline emissions. Per mass emitted, the gas-phase organic compounds in gasoline exhaust have the largest potential impact on ozone production with over half of the ozone formation due to products of incomplete combustion (e.g., alkenes and oxygenated VOCs). When combined with data on gasoline and diesel fuel sales in the U.S., these results indicate that gasoline sources are responsible for 69-96% of emissions and 79-97% of the ozone formation potential from gas-phase organic carbon emitted by motor vehicles. PMID:24011064

  17. BIOWINOL TECHNOLOGIES: A HYBRID GREEN PROCESS FOR BIOFUEL PRODUCTIONPHASE 2

    EPA Science Inventory

    The development of hollow fiber membrane (HFM) reactor will result in improved gas utilization that will positively impact overall process efficiencies. Successful completion of this project could result in the development of many decentralized biofuel production systems near ...

  18. Limonene ozonolysis in the presence of nitric oxide: Gas-phase reaction products and yields

    NASA Astrophysics Data System (ADS)

    Ham, Jason E.; Harrison, Joel C.; Jackson, Stephen R.; Wells, J. R.

    2016-05-01

    The reaction products from limonene ozonolysis were investigated using the new carbonyl derivatization agent, O-tert-butylhydroxylamine hydrochloride (TBOX). With ozone (O3) as the limiting reagent, five carbonyl compounds were detected. The yields of the carbonyl compounds are discussed with and without the presence of a hydroxyl radical (OHrad) scavenger, giving insight into the influence secondary OH radicals have on limonene ozonolysis products. The observed reaction product yields for limonaketone (LimaKet), 7-hydroxyl-6-oxo-3-(prop-1-en-2-yl)heptanal (7H6O), and 2-acetyl-5-oxohexanal (2A5O) were unchanged suggesting OHrad generated by the limonene + O3 reaction does not contribute to their formation. The molar yields of 3-isopropenyl-6-oxo-heptanal (IPOH) and 3-acetyl-6-oxoheptanal (3A6O) decreased by 68% and >95%; respectively, when OHrad was removed. This suggests that OHrad radicals significantly impact the formation of these products. Nitric oxide (NO) did not significantly affect the molar yields of limonaketone or IPOH. However, NO (20 ppb) considerably decreased the molar reaction product yields of 7H6O (62%), 2A5O (63%), and 3A6O (47%), suggesting NO reacted with peroxyl intermediates, generated during limonene ozonolysis, to form other carbonyls (not detected) or organic nitrates. These studies give insight into the transformation of limonene and its reaction products that can lead to indoor exposures.

  19. Limonene ozonolysis in the presence of nitric oxide: Gas-phase reaction products and yields

    PubMed Central

    Ham, Jason E.; Harrison, Joel C.; Jackson, Stephen R.; Wells, J.R.

    2016-01-01

    The reaction products from limonene ozonolysis were investigated using the new carbonyl derivatization agent, O-tert-butylhydroxylamine hydrochloride (TBOX). With ozone (O3) as the limiting reagent, five carbonyl compounds were detected. The yields of the carbonyl compounds are discussed with and without the presence of a hydroxyl radical (OH•) scavenger, giving insight into the influence secondary OH radicals have on limonene ozonolysis products. The observed reaction product yields for limonaketone (LimaKet), 7-hydroxyl-6-oxo-3-(prop-1-en-2-yl)heptanal (7H6O), and 2-acetyl-5-oxohexanal (2A5O) were unchanged suggesting OH• generated by the limonene + O3 reaction does not contribute to their formation. The molar yields of 3-isopropenyl-6-oxo-heptanal (IPOH) and 3-acetyl-6-oxoheptanal (3A6O) decreased by 68% and >95%; respectively, when OH• was removed. This suggests that OH• radicals significantly impact the formation of these products. Nitric oxide (NO) did not significantly affect the molar yields of limonaketone or IPOH. However, NO (20 ppb) considerably decreased the molar reaction product yields of 7H6O (62%), 2A5O (63%), and 3A6O (47%), suggesting NO reacted with peroxyl intermediates, generated during limonene ozonolysis, to form other carbonyls (not detected) or organic nitrates. These studies give insight into the transformation of limonene and its reaction products that can lead to indoor exposures. PMID:27346977

  20. A (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer)-dispersed sustained-release tablet for imperialine to simultaneously prolong the drug release and improve the oral bioavailability.

    PubMed

    Lin, Qing; Fu, Yu; Li, Jia; Qu, Mengke; Deng, Li; Gong, Tao; Zhang, Zhirong

    2015-11-15

    Imperialine, extracted from Bulbus Fritillariae Cirrhosae, is an efficient antitussive and expectorant medicine. However, its short half-life and stomach degradation limited imperialine from further clinical use. The current study was conducted to develop a sustained-release tablet for imperialine both to prolong absorption time and to improve the oral bioavailability of the drug. The tablets were prepared by a direct compression method formulated on optimized solid dispersion (SD) for imperialine based on polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus(®)) with imperialine/Soluplus(®) ratio of 1:8 (w/w). In order to obtain the optimized formulation, factors that affected the drug release were investigated by in vitro dissolution studies in the media of pH1.2, 5.8, 7.0 and 7.4. Powder X-ray diffraction and scanning electron microscope confirmed that the imperialine in SD was amorphous instead of crystalline, and still stayed amorphous even after the direct compression. And besides, pharmacokinetic study in Beagle dogs was performed to inspect the in vivo sustained release. Plasma concentration-time curves and pharmacokinetic parameters were gained. As a result, the Cmax of imperialine was one-fold reduced and Tmax was two-fold prolonged, and the mean AUC0-24 was expressed as 89.581±21.243μgh/L, which showed that the oral bioavailability of imperialine was 2.46-fold improved. Moreover, the in vitro-in vivo correlation was recommended to carry out, demonstrating the percentages of drug release in vitro were well-correlated with the absorptive fraction in vivo with the correlation coefficients above 0.9900. By mathematically modeling and moment imaging of the drug release, Peppas equation was selected as the most fitted model for the sustained-release tablets with the diffusional coefficient in the range of 0.59-0.62, indicating the release of imperialine from the sustained-release tablets was an anomalous process involving

  1. Production of non-gaussianities through a positive spatial curvature bouncing phase

    SciTech Connect

    Gao, Xian; Lilley, Marc; Peter, Patrick E-mail: marc.lilley@uct.ac.za

    2014-07-01

    We compute the level of non-gaussianities produced by a cosmological bouncing phase in the minimal non-singular setup that lies within the context of General Relativity when the matter content consists of a simple scalar field with a standard kinetic term. Such a bouncing phase is obtained by requiring that the spatial sections of the background spacetime be positively curved. We restrict attention to the close vicinity of the bounce by Taylor expanding the scale factor a(η), the scalar field φ(η) and the potential V(φ) in powers of the conformal time η around the bounce. We find that possibly large non-gaussianities are generically produced at the bounce itself and also discuss which shapes of non-gaussianities are most likely to be produced.

  2. Germanium x-ray phase plates for the production of circularly polarized x-rays

    SciTech Connect

    Yahnke, C.J.; Srajer, G.; Haeffner, D.R.; Mills, D.M.; Assoufid, L.

    1993-10-01

    The authors have constructed an x-ray phase plate to produce both linearly and circularly polarized x-rays at discrete energies between 20 keV and 88 keV. The plate is a monolithic two-crystal design, constructed from germanium, which increases the resultant degree of circular polarization of the output beam. They have measured the degree of circular polarization at 65 keV to be 90% {+-} 4%, significantly better than that produced by silicon phase plates. This radiation was used to measure the magnetic Compton profile for Fe, which was found to be in good agreement with theory and previous work. The underlying x-ray optics and the characterization of the device between 62 keV and 93 keV at the Cornell High Energy Synchrotron Source are presented.

  3. Chemical and Phase Evolution of Amorphous Molybdenum Sulfide Catalysts for Electrochemical Hydrogen Production.

    PubMed

    Lee, Sang Chul; Benck, Jesse D; Tsai, Charlie; Park, Joonsuk; Koh, Ai Leen; Abild-Pedersen, Frank; Jaramillo, Thomas F; Sinclair, Robert

    2016-01-26

    Amorphous MoSx is a highly active, earth-abundant catalyst for the electrochemical hydrogen evolution reaction. Previous studies have revealed that this material initially has a composition of MoS3, but after electrochemical activation, the surface is reduced to form an active phase resembling MoS2 in composition and chemical state. However, structural changes in the MoSx catalyst and the mechanism of the activation process remain poorly understood. In this study, we employ transmission electron microscopy (TEM) to image amorphous MoSx catalysts activated under two hydrogen-rich conditions: ex situ in an electrochemical cell and in situ in an environmental TEM. For the first time, we directly observe the formation of crystalline domains in the MoSx catalyst after both activation procedures as well as spatially localized changes in the chemical state detected via electron energy loss spectroscopy. Using density functional theory calculations, we investigate the mechanisms for this phase transformation and find that the presence of hydrogen is critical for enabling the restructuring process. Our results suggest that the surface of the amorphous MoSx catalyst is dynamic: while the initial catalyst activation forms the primary active surface of amorphous MoS2, continued transformation to the crystalline phase during electrochemical operation could contribute to catalyst deactivation. These results have important implications for the application of this highly active electrocatalyst for sustainable H2 generation. PMID:26624225

  4. Rapid purification of fumonisins and their hydrolysis products with solid-phase extraction columns.

    PubMed

    Poling, S M; Plattner, R D

    1999-06-01

    Fumonisins B(3) and B(4) (FB(3) and FB(4)) were recovered from the 50:50 acetonitrile/water extract of corn cultures of a strain of Fusarium moniliforme that does not make FB(1) or FB(2) by stirring the extract with IRA-68, a weak anion-exchange resin. The fumonisins were desorbed with 5% acetic acid in the same solvent. After dilution with water, the desorbed fumonisins were separated into FB(3) (FB(3) and FA(3)) and FB(4) (FB(4), FC(4), and FA(4)) fractions with a tC(18) solid-phase extraction (SPE) cartridge. The FB(3) fraction was then separated into FB(3) and FA(3) by using an NH(2) SPE cartridge and eluting with 5% acetic acid and increasing amounts of acetonitrile in water. Finally, FB(1) and FA(3) were hydrolyzed with calcium hydroxide. After recovery from the reaction mixture using a tC(18) cartridge, the hydrolyzed and partially hydrolyzed analogues were separated and the unreacted fumonisins recovered by using an NH(2) cartridge, initially in the normal-phase mode with increasing amounts of water in acetonitrile and then in the reversed-phase mode after the addition of 5% acetic acid to the solvent and eluting in the reverse order. PMID:10794634

  5. Microfluidic Production of Semipermeable Microcapsules by Polymerization-Induced Phase Separation.

    PubMed

    Kim, Bomi; Jeon, Tae Yoon; Oh, You-Kwan; Kim, Shin-Hyun

    2015-06-01

    Semipermeable microcapsules are appealing for controlled release of drugs, study of cell-to-cell communication, and isolation of enzymes or artificial catalysts. Here, we report a microfluidic strategy for creating monodisperse microcapsules with size-selective permeability using polymerization-induced phase separation. Monodisperse water-in-oil-in-water (W/O/W) double-emulsion drops, whose ultrathin middle layer is composed of photocurable resin and inert oil, are generated in a capillary microfluidic device, and irradiated by UV light. Upon UV illumination, the monomers are photopolymerized, which leads to phase separation between the polymerized resin and the oil within the ultrathin shell. Subsequent dissolution of the oil leaves behind regular pores in the polymerized membrane that interconnect the interior and exterior of the microcapsules, thereby providing size-selective permeability. The degree of phase separation can be further tuned by adjusting the fraction of oil in the shell or the affinity of the oil to the monomers, thereby enabling the control of the cutoff value of permeation. High mechanical stability and chemical resistance of the microcapsules, as well as controllable permeability and high encapsulation efficiency, will provide new opportunity in a wide range of applications. PMID:26020458

  6. The Phase Behavior Effect on the Reaction Engineering of Transesterification Reactions and Reactor Design for Continuous Biodiesel Production

    NASA Astrophysics Data System (ADS)

    Csernica, Stephen N.

    transitions from two phases to a single phase, or pseudo-single phase. The transition to a single phase or pseudo-single phase is a function of the methanol content. Regardless, the maximum observed reaction rate occurs at the point of the phase transition, when the concentration of triglycerides in the methanol phase is largest. The phase transition occurs due to the accumulation of the primary product, biodiesel methyl esters. Through various experiments, it was determined that the rate of the triglyceride mass transfer into the methanol phase, as well as the solubility of triglycerides in methanol, increases with increasing methyl ester concentration. Thus, there exists some critical methyl ester concentration which favors the formation of a single or pseudo-single phase system. The effect of the by-product glycerol on the reaction kinetics was also investigated. It was determined that at low methanol to triglyceride molar ratios, glycerol acts to inhibit the reaction rate and limit the overall triglyceride conversion. This occurs because glycerol accumulates in the methanol phase, i.e. the primary reaction volume. When glycerol is at relatively high concentrations within the methanol phase, triglycerides become excluded from the reaction volume. This greatly reduces the reaction rate and limits the overall conversion. As the concentration of methanol is increased, glycerol becomes diluted and the inhibitory effects become dampened. Assuming pseudo-homogeneous phase behavior, a simple kinetic model incorporating the inhibitory effects of glycerol was proposed based on batch reactor data. The kinetic model was primarily used to theoretically compare the performance of different types of continuous flow reactors for continuous biodiesel production. It was determined that the inhibitory effects of glycerol result in the requirement of very large reactor volumes when using continuous stirred tank reactors (CSTR). The reactor volume can be greatly reduced using tubular style

  7. Gas-phase chemistry of transition-metal ions with alkanes: do initial electrostatic interaction control final product distributions

    SciTech Connect

    Hankinson, D.J.; Allison, J.

    1987-09-24

    There are features of the dynamics of gas-phase ion/molecule reactions that make them unique when compared to neutral/neutral reactions and solution processes. Exceedingly rich and complex chemistry can be observed in gas-phase systems in which a reactant is charged, due, in part, to the relatively long lifetime of the ion/molecule complex that is initially formed. Here possible correlations between final reaction products and geometry-specific complexes that are initially formed are discussed. The chemistry under study is that for univalent first-row transition-metal ions with n-butane, in which cleavage of C-H and C-C bonds is observed for some metals.

  8. The inclusion of ergonomic tools in the informational, conceptual and preliminary phases of the product design methodology.

    PubMed

    Medeiros, Ivan Luiz de; Batiz, Eduardo Concepción

    2012-01-01

    The process of product development has received special attention as it is being recognized as a source of competitive gain. Through its systematic use companies reduce costs, increase quality and decrease development time. However, one can find products being launched on the market that cause dissatisfaction to its users, and in consequence if the customer feels harmed or injured he will no longer purchase a product from the same brand. This in regard only to the commercial aspect; usually the danger of an accident or injury is not even thought about. This paper is the basis of the dissertation master's degree and used a literature research to build the repertoire, analyzing the methodologies applied by product design engineers, designers and ergonomists. The analysis results demonstrate the inefficiency of the design methodologies ergonomic issues. The contribution of this work lies in the suggestion to include ergonomic tools in all phases of product development and the presentation of a table with the tools that points out its most suitable time of application and results. PMID:22316854

  9. Ultraviolet-gas phase and -photocatalytic synthesis from CO and NH3. [photolysis products

    NASA Technical Reports Server (NTRS)

    Hubbard, J. S.; Voecks, G. E.; Hobby, G. L.; Ferris, J. P.; Williams, E. A.; Nicodem, D. E.

    1975-01-01

    Ammonium cyanate is identified as the major product of the photolysis of gaseous NH3-CO mixtures at 206.2 or 184.9 nm. Lesser amounts of urea, biurea, biuret semicarbazide, formamide and cyanide are observed. A series of 18 reactions underlying the formation of photolysis products is presented and discussed. Photocatalytic syntheses of C-14-urea, -formamide, and -formaldehyde are carried out through irradiation of (C-14)O and NH3 in the presence of Vycor, silica gel, or volcanic ash shale surfaces. The possible contributions of the relevant reactions to the abiotic synthesis of organic nitrogen compounds on Mars, the primitive earth, and in interstellar space are examined.

  10. NATO/CCMS PILOT STUDY - CLEAN PRODUCTS AND PROCESSES (PHASE I) 2000 ANNUAL REPORT, NUMBER 242

    EPA Science Inventory

    This annual report presents the proceedings of the Third Annual NATO/CCMS pilot study meeting in Copenhagen, Denmark. Guest speakers focused on efforts in the area of research of clean products and processes, life cycle analysis, computer tools and pollution prevention.

  11. Particulate and gas-phase products from the atmospheric degradation of chlorpyrifos and chlorpyrifos-oxon

    NASA Astrophysics Data System (ADS)

    Borrás, Esther; Ródenas, Milagros; Vázquez, Mónica; Vera, Teresa; Muñoz, Amalia

    2015-12-01

    The phosphorothioate structure is highly present in several pesticides. However, there is a lack of information about its degradation process in air and the secondary pollutants formed. Herein, the atmospheric reactions of chlorpyrifos, one of the most world-used insecticide, and its main degradation product - chlorpyrifos-oxon - are described. The photo-oxidation under the presence of NOx was studied in a large outdoor simulation chamber for both chlorpyrifos and chlorpyrifos-oxon, observing a rapid degradation (Half lifetime < 3.5 h for both compounds). Also, the photolysis reactions of both were studied. The formation of particulate matter (aerosol mass yield ranged 6-59%) and gaseous products were monitored. The chemical composition of minor products was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as 3,5,6-trichloropyridin-2-ol and ethyl 3,5,6-trichloropyridin-2-yl hydrogen phosphate. An atmospheric degradation mechanism has been amplified based on an oxidation started with OH-nucleophilic attack to Pdbnd S bond.

  12. Gas-Phase Oxidation Kinetics and Organic Aerosol Products of Ethanolamine

    NASA Astrophysics Data System (ADS)

    Borduas, N.; Abbatt, J.; Murphy, J. G.

    2012-12-01

    Ethanolamine is currently the solvent of choice in carbon capture and storage technology (CCS) which aims to reduce CO2 emissions to the atmosphere in coal powered pilot plants. CCS technology represents an unprecedented large scale application of ethanolamine and little is known of its fate if it was unintentionally released into the atmosphere. Relative kinetic experiments were conducted in a 1m3 smog chamber using online proton-transfer-reaction mass spectrometry. The kinetics of oxidation with hydroxyl radicals from light and dark sources converge to a value of (7.6 ± 1.1) x 10-11 cm3 molec-1 s-1. The reaction of ethanolamine with ozone was determined to be (1.05 ± 0.08) x 10-18 cm3 molec-1 s-1. We find that ethanolamine has a short lifetime in the atmosphere and readily deposits onto wall and particle surfaces, as observed by considerable formation of organonitrogen aerosol products. An investigation into the oxidation product formation using a combination of reagent ions with online chemical ionization mass spectrometry approaches lead to the detection of higher order products. The formation of these high molecular weight products is simultaneous with the oxidation of ethanolamine and implies substantial organic aerosol chemistry.

  13. AMMONIA REMOVAL AND NITROUS OXIDE PRODUCTION IN GAS-PHASE COMPOST BIOFILTERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofiltration technology is widely utilized for treating ammonia gas (NH3), with one of its potential detrimental by-products being nitrous oxide (N2O), a greenhouse gas approximately 300 times more reactive to infrared than CO2. The present work intends to provide the relation between NH3 removal d...

  14. NOVEL CHROMATOGRAPHIC SEPARATION AND CARBON SOLID PHASE EXTRACTION OF ACETANILIDE HERBICIDE DEGRADATION PRODUCTS

    EPA Science Inventory

    Six acetanilide herbicides are currently registered for use in the U.S. Over the past several years, ethanesufonic acid (ESA) and oxanilic acid (OA) degradatoin products of these acetanilide herbicides have been found in U.S. ground waters and surface waters. "Alachlor ESA and ...

  15. Analysis of Historic Data for Juvenile and Adult Salmonid Production. Phase 1, Final Report.

    SciTech Connect

    Hilborn, Ray; Pascual, Miguel; Donnelly, Robert; Coronado-Hernadez, Claribel

    1993-11-01

    Survival of hatchery reared Columbia River chinook (Oncorhynchus tshawytscha) salmon from release to return is highly variable and thought to be related to river flow during juvenile outmigration in the spring. The purpose of this project is to examine the relationship between survival of coded-wire-tagged (CWT) Columbia River salmonids and in-river flow and other freshwater factors. This report covers Phase 1, in which two methods to estimate survival were developed and evaluated, and criteria for data selection were established.

  16. Gas-phase molecular halogen production from sea-salt particles via interface reactions

    NASA Astrophysics Data System (ADS)

    Jimenez-Aranda, A.; Thomas, J.; Finlayson-Pitts, B. J.; Dabdub, D.

    2005-12-01

    Interface reactions at the surface of sea-salt particles have been suggested as an important source of photolyzable gas-phase halogen species in the troposphere. Such reactions are plausible, given theoretical evidence for ions at interfaces, predicted enhancements of some gases at the air-water interface, and the results of a number of experiments in which interface reactions had to be invoked to explain the data. Because of the contributions of halogen chemistry in determining ozone and other trace species in the troposphere, elucidating the roles of interface and bulk chemistry in generating photolyzable halogen gases is important. A revised version of the model of aerosol, gas and interfacial chemistry (MAGIC 2.0) is used in this work to examine the reactions of chloride and bromide ions with OH and O3. The goal is to understand the factors that determine the relative importance of bulk compared to interface chemistry in the most simple chloride and bromide systems represented by deliquesced aerosols of NaCl or NaBr. Results show the interface process involving Cl- and OH(g) is the main source of Cl2(g). For the analogous oxidation of bromide by OH, gaseous Br2 is formed mainly in the bulk aqueous phase and transferred across the interface. However, the reaction of Br- with O3(g) at the interface is the primary source of Br2(g) under dark conditions.

  17. The gas-phase on-line production of vanadium oxytrihalides, VOX 3 and their identification by infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Zidan, Mohammed D.; Allaf, Abdul W.

    2000-12-01

    A new route has been devised, leading to the production of VOX 3 molecules where XF, Br and I by an on-line process using vanadium oxytrichloride, VOCl 3 as a starting compound passed over the following heated salts NaF, KBr and KI at 375, 700 and 550°C, respectively. The products have been characterized by the IR spectra of their vapors. The low resolution gas phase on-line Fourier transform infrared spectra reported for the first time show strong bands with PQR type structure, centered at 1058, 1035, 1030 and 1025 cm -1 assigned to the ν1( a1), the OV stretching fundamental mode of VOF 3, VOCl 3, VOBr 3 and VOI 3, respectively.

  18. Aqueous Phase Glycerol Reforming by PtMo Bimetallic Nano-Particle Catalyst: Product Selectivity and Structural Characterization

    SciTech Connect

    Stach E. A.; Dietrich, P.J.; Lobo-Lapidus, R.J.; Wu, T.; Sumer, A.; Akatay, M.C.; Fingland, B.R.; Guo, N.; Dumesic, J.A.; Marshall, C.L.; Jellinek, J.; Delgass, W.N.; Ribeiro, F.H.; Miller, J.T.

    2012-03-01

    A carbon supported PtMo aqueous phase reforming catalyst for producing hydrogen from glycerol was characterized by analysis of the reaction products and pathway, TEM, XPS and XAS spectroscopy. Operando X-ray absorption spectroscopy (XAS) indicates the catalyst consists of bimetallic nano-particles with a Pt rich core and a Mo rich surface. XAS of adsorbed CO indicates that approximately 25% of the surface atoms are Pt. X-ray photoelectron spectroscopy indicates that there is unreduced and partially reduced Mo oxide (MoO{sub 3} and MoO{sub 2}), and Pt-rich PtMo bimetallic nano-particles. The average size measured by transmission electron microscopy of the fresh PtMo nano-particles is about 2 nm, which increases in size to 5 nm after 30 days of glycerol reforming at 31 bar and 503 K. The catalyst structure differs from the most energetically stable structure predicted by density functional theory (DFT) calculations for metallic Pt and Mo atoms. However, DFT indicates that for nano-particles composed of metallic Pt and Mo oxide, the Mo oxide is at the particle surface. Subsequent reduction would lead to the experimentally observed structure. The aqueous phase reforming reaction products and intermediates are consistent with both C-C and C-OH bond cleavage to generate H{sub 2}/CO{sub 2} or the side product CH{sub 4}. While the H{sub 2} selectivity at low conversion is about 75%, cleavage of C-OH bonds leads to liquid products with saturated carbon atoms. At high conversions (to gas), these will produced additional CH{sub 4} reducing the H{sub 2} yield and selectivity.

  19. Experimental productivity rate optimization of rare earth element separation through preparative solid phase extraction chromatography.

    PubMed

    Knutson, Hans-Kristian; Max-Hansen, Mark; Jönsson, Christian; Borg, Niklas; Nilsson, Bernt

    2014-06-27

    Separating individual rare earth elements from a complex mixture with several elements is difficult and this is emphasized for the middle elements: Samarium, Europium and Gadolinium. In this study we have accomplished an overloaded one-step separation of these rare earth elements through preparative ion-exchange high-performance liquid chromatography with an bis (2-ethylhexyl) phosphoric acid impregnated column and nitric acid as eluent. An inductively coupled plasma mass spectrometry unit was used for post column element detection. The main focus was to optimize the productivity rate, subject to a yield requirement of 80% and a purity requirement of 99% for each element, by varying the flow rate and batch load size. The optimal productivity rate in this study was 1.32kgSamarium/(hmcolumn(3)), 0.38kgEuropium/(hmcolumn(3)) and 0.81kgGadolinium/(hmcolumn(3)). PMID:24835593

  20. Comparing the environmental footprints of home-care and personal-hygiene products: the relevance of different life-cycle phases.

    PubMed

    Koehler, Annette; Wildbolz, Caroline

    2009-11-15

    An in-depth life-cycle assessment of nine home-care and personal-hygiene products was conducted to determine the ecological relevance of different life-cycle phases and compare the environmental profiles of products serving equal applications. Using detailed data from industry and consumer-behavior studies a broad range of environmental impacts were analyzed to identify the main drivers in each life-cycle stage and potentials for improving the environmental footprints. Although chemical production significantly adds to environmental burdens, substantial impacts are caused in the consumer-use phase. As such, this research provides recommendations for product development, supply chain management, product policies, and consumer use. To reduce environmental burdens products should, for instance, be produced in concentrated form, while consumers should apply correct product dosages and low water temperatures during product application. PMID:20028065

  1. Liquid phase products and solid deposit formation from thermally stressed model jet fuels

    NASA Technical Reports Server (NTRS)

    Kim, W. S.; Bittker, D. A.

    1984-01-01

    The relationship between solid deposit formation and liquid degradation product concentration was studied for the high temperature (400 C) stressing of three hydrocarbon model fuels. A Jet Fuel Thermal Oxidation Tester was used to simulate actual engine fuel system conditions. The effects of fuel type, dissolved oxygen concentration, and hot surface contact time (reaction time) were studied. Effects of reaction time and removal of dissolved oxygen on deposit formation were found to be different for n-dodecane and for 2-ethylnaphthalene. When ten percent tetralin is added to n-dodecane to give a simpler model of an actual jet fuel, the tetralin inhibits both the deposit formation and the degradation of n-dodecane. For 2-ethylnaphthalene primary product analyses indicate a possible self-inhibition at long reaction times of the secondary reactions which form the deposit precursors. The mechanism of the primary breakdown of these fuels is suggested and the primary products which participate in these precursor-forming reactions are identified. Some implications of the results to the thermal degradation of real jet fuels are given.

  2. Sorption enhanced reaction process for production of hydrogen. Phase 1 final report

    SciTech Connect

    Mayorga, S.G.; Hufton, J.R.; Sircar, S.; Gaffney, T.R.

    1997-07-01

    Hydrogen is one of the most suitable energy sources from both technological and environmental perspectives for the next century, especially in the context of a sustainable global energy economy. The most common industrial process to produce high-purity (99.99+ mol%) hydrogen is to reform natural gas by a catalytic reaction with steam at a high temperature. Conventional steam-methane reforming (SMR) contributed to approximately 2.4 billion standard cubic feet per day (SCFD) of hydrogen production in the US. By 1998, the growth of SMR-produced hydrogen in the US is expected to reach 3.4 billion SCFD, with the increased demand attributed to hydrogen`s use in reformulated gasolines required by the Clean Air Act. The goal of this work is to develop an even more efficient process for reforming steam and methane to hydrogen product than the conventional SMR process. The application of Sorption Enhanced Reaction (SER) technology to SMR has the potential to markedly reduce the cost of hydrogen through lower capital and energy requirements. The development of a more cost-effective route to hydrogen production based on natural gas as the primary energy source will accelerate the transition to a more hydrogen-based economy in the future. The paper describes the process, which includes a sorbent for CO{sub 2} removal, and the various tasks involved in its development.

  3. COMMERCIALIZATION OF AN ATMOSPHERIC IRON-BASED CDCL PROCESS FOR POWER PRODUCTION. PHASE I: TECHNOECONOMIC ANALYSIS

    SciTech Connect

    Vargas, Luis

    2013-11-01

    Coal Direct Chemical Looping (CDCL) is an advanced oxy-combustion technology that has potential to enable substantial reductions in the cost and energy penalty associated with carbon dioxide (CO2) capture from coal-fired power plants. Through collaborative efforts, the Babcock & Wilcox Power Generation Group (B&W) and The Ohio State University (OSU) developed a conceptual design for a 550 MWe (net) supercritical CDCL power plant with greater than 90% CO2 capture and compression. Process simulations were completed to enable an initial assessment of its technical performance. A cost estimate was developed following DOE’s guidelines as outlined in NETL’s report “Quality Guidelines for Energy System Studies: Cost Estimation Methodology for NETL Assessments of Power Plant Performance”, (2011/1455). The cost of electricity for the CDCL plant without CO2 Transportation and Storage cost resulted in $ $102.67 per MWh, which corresponds to a 26.8 % increase in cost of electricity (COE) when compared to an air-fired pulverized-coal supercritical power plant. The cost of electricity is strongly depending on the total plant cost and cost of the oxygen carrier particles. The CDCL process could capture further potential savings by increasing the performance of the particles and reducing the plant size. During the techno-economic analysis, the team identified technology and engineering gaps that need to be closed to bring the technology to commercialization. The technology gaps were focused in five critical areas: (i) moving bed reducer reactor, (ii) fluidized bed combustor, (iii) particle riser, (iv) oxygen-carrier particle properties, and (v) process operation. The key technology gaps are related to particle performance, particle manufacturing cost, and the operation of the reducer reactor. These technology gaps are to be addressed during Phase II of project. The project team is proposing additional lab testing to be completed on the particle and a 3MWth pilot facility

  4. Production of Liquid Alkanes by Aqueous-Phase Processing of Biomass-Derived Carbohydrates

    NASA Astrophysics Data System (ADS)

    Huber, George W.; Chheda, Juben N.; Barrett, Christopher J.; Dumesic, James A.

    2005-06-01

    Liquid alkanes with the number of carbon atoms ranging from C7 to C15 were selectively produced from biomass-derived carbohydrates by acid-catalyzed dehydration, which was followed by aldol condensation over solid base catalysts to form large organic compounds. These molecules were then converted into alkanes by dehydration/hydrogenation over bifunctional catalysts that contained acid and metal sites in a four-phase reactor, in which the aqueous organic reactant becomes more hydrophobic and a hexadecane alkane stream removes hydrophobic species from the catalyst before they go on further to form coke. These liquid alkanes are of the appropriate molecular weight to be used as transportation fuel components, and they contain 90% of the energy of the carbohydrate and H2 feeds.

  5. Declines in polybrominated diphenyl ether contamination of San Francisco Bay following production phase-outs and bans.

    PubMed

    Sutton, Rebecca; Sedlak, Margaret D; Yee, Donald; Davis, Jay A; Crane, David; Grace, Richard; Arsem, Nirmela

    2015-01-20

    California has implemented unique consumer product flammability standards. Polybrominated diphenyl ether (PBDE) flame retardants were once widely incorporated into products to meet these standards, but concerns regarding toxicity and accumulation in humans and biota led to nationwide phase-outs and state bans. A decade of PBDE monitoring in San Francisco Bay has resulted in a data set that covers periods during and after PBDE use and consists of hundreds of measurements of water, sediment, and biota. While PBDEs remain widely detected in biota, levels have declined by nearly half in sport fish and 74-95% in bivalves and bird eggs. Concentrations of BDE-47 in sediment have dropped by over one-third from 2002 to 2012; in water, a decline is not yet evident. The dominant congener in sediment, DecaBDE component BDE-209, showed no temporal trend. U.S. production of DecaBDE ended in 2013; future monitoring may reveal declines. Overall, the data indicate that reduced production can result in relatively rapid reductions in the concentrations of some hydrophobic contaminants in biota and sediment, particularly when implemented after only a few decades of heavy use. Recent changes to California's flammability standards may lessen the use of other flame retardants and similarly reduce Bay contamination. PMID:25544014

  6. Biohydrogen production in a three-phase fluidized bed bioreactor using sewage sludge immobilized by ethylene-vinyl acetate copolymer.

    PubMed

    Lin, Chi-Neng; Wu, Shu-Yii; Chang, Jian-Sheng; Chang, Jo-Shu

    2009-07-01

    Ethylene-vinyl acetate (EVA) copolymer was used to immobilize H(2)-producing sewage sludge for H(2) production in a three-phase fluidized bed reactor (FBR). The FBR with an immobilized cell packing ratio of 10% (v/v) and a liquid recycle rate of 5l/min (23% bed expansion) was optimal for dark H(2) fermentation. The performance of the FBR reactor fed with sucrose-based synthetic medium was examined under various sucrose concentration (C(so)) and hydraulic retention time (HRT). The best volumetric H(2) production rate of 1.80+/-0.02 H(2) l/h/l occurred at C(so)=40 g COD/l and 2h HRT, while the optimal H(2) yield (4.26+/-0.04 mol H(2)/mol sucrose) was obtained at C(so)=20 g COD/l and 6h HRT. The H(2) content in the biogas was stably maintained at 40% or above. The primary soluble metabolites were butyric acid and acetic acid, as both products together accounted for 74-83% of total soluble microbial products formed during dark H(2) fermentation. PMID:19318247

  7. SEPARATION AND QUANTITATION OF NITROBENZENES AND THEIR REDUCTION PRODUCTS NITROANILINES AND PHENYLENEDIAMINES BY REVERSED=PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

    EPA Science Inventory

    A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of a mixture consisting of nitrobenzene, dinitrobenzene isomers, 1,3,5-trinitrobenzene and their reduction products: aniline, nitroanilines and phenylenediamines has been developed...

  8. Comparison of the MODIS Multilayer Cloud Detection and Thermodynamic Phase Products with CALIPSO and CloudSat

    NASA Technical Reports Server (NTRS)

    Platnick, Steven; King, Michael D.; Wind, Gala; Holz, Robert E.; Ackerman, Steven A.; Nagle, Fred W.

    2008-01-01

    CALIPSO and CloudSat, launched in June 2006, provide global active remote sensing measurements of clouds and aerosols that can be used for validation of a variety of passive imager retrievals derived from instruments flying on the Aqua spacecraft and other A-Train platforms. The most recent processing effort for the MODIS Atmosphere Team, referred to as the "Collection 5" stream, includes a research-level multilayer cloud detection algorithm that uses both thermodynamic phase information derived from a combination of solar and thermal emission bands to discriminate layers of different phases, as well as true layer separation discrimination using a moderately absorbing water vapor band. The multilayer detection algorithm is designed to provide a means of assessing the applicability of 1D cloud models used in the MODIS cloud optical and microphysical product retrieval, which are generated at a 1 h resolution. Using pixel-level collocations of MODIS Aqua, CALIOP, and CloudSat radar measurements, we investigate the global performance of the thermodynamic phase and multilayer cloud detection algorithms.

  9. Production of a Biomimetic Fe(I)-S Phase on Pyrite by Atomic-Hydrogen Beam-Surface Reactive Scattering

    PubMed Central

    Che, Li; Gardenghi, David J.; Szilagyi, Robert K.; Minton, Timothy K.

    2011-01-01

    Molecular beam-surface scattering and X-ray absorption spectroscopic experiments were employed to study the reaction of deuterium atoms with a pyrite, FeS2 (100), surface and to investigate the electronic and geometric structures of the resulting Fe-S phases. Incident D atoms, produced by a radio frequency plasma and expanded in an effusive beam, were directed at a pyrite surface held at various temperatures from ambient up to 200 °C. During exposure to the D-atom beam, D2S products were released with a thermal distribution of molecular speeds, indicating that the D atoms likely reacted in thermal equilibrium with the surface. The yield of D2S from the surface decreased approximately exponentially with exposure duration, suggesting that the surface accessible sulfur atoms were depleted, thus leaving an iron-rich surface. This conclusion is consistent with X-ray absorption measurements of the exposed surfaces, which indicated the formation of a layered structure, with elemental iron as the outermost layer on top of a formally Fe(I)-S phase as an intermediate layer and a formally Fe(II)-S2 bulk pyrite layer at lower depths. The reduced Fe(I)-S phase is particularly remarkable because of its similarity to the catalytically active sites of small molecule metalloenzymes, such as FeFe-hydrogenases and MoFe-nitrogenases. PMID:21526811

  10. Hydrogen production by supercritical water gasification of biomass. Phase 1 -- Technical and business feasibility study, technical progress report

    SciTech Connect

    1997-12-01

    The nine-month Phase 1 feasibility study was directed toward the application of supercritical water gasification (SCWG) for the economical production and end use of hydrogen from renewable energy sources such as sewage sludge, pulp waste, agricultural wastes, and ultimately the combustible portion of municipal solid waste. Unique in comparison to other gasifier systems, the properties of supercritical water (SCW) are ideal for processing biowastes with high moisture content or contain toxic or hazardous contaminants. During Phase I, an end-to-end SCWG system was evaluated. A range of process options was initially considered for each of the key subsystems. This was followed by tests of sewage sludge feed preparation, pumping and gasification in the SCW pilot plant facility. Based on the initial process review and successful pilot-scale testing, engineering evaluations were performed that defined a baseline system for the production, storage and end use of hydrogen. The results compare favorably with alternative biomass gasifiers currently being developed. The results were then discussed with regional wastewater treatment facility operators to gain their perspective on the proposed commercial SCWG systems and to help define the potential market. Finally, the technical and business plans were developed based on perceived market needs and the projected capital and operating costs of SCWG units. The result is a three-year plan for further development, culminating in a follow-on demonstration test of a 5 MT/day system at a local wastewater treatment plant.

  11. Evaluation of Selected Chemical Processes for Production of Low-cost Silicon, Phase 3

    NASA Technical Reports Server (NTRS)

    Blocher, J. M., Jr.; Browning, M. F.

    1979-01-01

    The construction of the 50 MT Si/year experimental process system development unit was deferred until FY 1980, and the fluidized bed, zinc vaporizer, by-product condenser, and electrolytic cell were combined with auxiliary units, capable of supporting 8-hour batchwise operation, to form the process development unit (PDU), which is scheduled to be in operation by October 1, 1979. The design of the PDU and objectives of its operation are discussed. Experimental program support activities described relate to: (1) a wetted-wall condensor; (2) fluidized-bed modeling; (3) zinc chloride electrolysis; and (4) zinc vaporizer.

  12. Liquid phase low temperature method for production of methanol from synthesis gas and catalyst formulations therefor

    DOEpatents

    Mahajan, Devinder

    2005-07-26

    The invention provides a homogenous catalyst for the production of methanol from purified synthesis gas at low temperature and low pressure which includes a transition metal capable of forming transition metal complexes with coordinating ligands and an alkoxide, the catalyst dissolved in a methanol solvent system, provided the transition metal complex is not transition metal carbonyl. The coordinating ligands can be selected from the group consisting of N-donor ligands, P-donor ligands, O-donor ligands, C-donor ligands, halogens and mixtures thereof.

  13. Gas phase formation of extremely oxidized pinene reaction products in chamber and ambient air

    NASA Astrophysics Data System (ADS)

    Ehn, M.; Kleist, E.; Junninen, H.; Petäjä, T.; Lönn, G.; Schobesberger, S.; Dal Maso, M.; Trimborn, A.; Kulmala, M.; Worsnop, D. R.; Wahner, A.; Wildt, J.; Mentel, Th. F.

    2012-06-01

    High molecular weight (300-650 Da) naturally charged negative ions have previously been observed at a boreal forest site in Hyytiälä, Finland. The long-term measurements conducted in this work showed that these ions are observed practically every night between spring and autumn in Hyytiälä. The ambient mass spectral patterns could be reproduced in striking detail during additional measurements of α-pinene (C10H16) oxidation at low-OH conditions in the Jülich Plant Atmosphere Chamber (JPAC). The ions were identified as clusters of the nitrate ion (NO3-) and α-pinene oxidation products reaching oxygen to carbon ratios of 0.7-1.3, while retaining most of the initial ten carbon atoms. Attributing the ions to clusters instead of single molecules was based on additional observations of the same extremely oxidized organics in clusters with HSO4- (Hyytiälä) and C3F5O2- (JPAC). The most abundant products in the ion spectra were identified as C10H14O7, C10H14O9, C10H16O9, and C10H14O11. The mechanism responsible for forming these molecules is still not clear, but the initial reaction is most likely ozone attack at the double bond, as the ions are mainly observed under dark conditions. β-pinene also formed highly oxidized products under the same conditions, but less efficiently, and mainly C9 compounds which were not observed in Hyytiälä, where β-pinene on average is 4-5 times less abundant than α-pinene. Further, to explain the high O/C together with the relatively high H/C, we propose that geminal diols and/or hydroperoxide groups may be important. We estimate that the night-time concentration of the sum of the neutral extremely oxidized products is on the order of 0.1-1 ppt (~106-107 molec cm-3). This is in a similar range as the amount of gaseous H2SO4 in Hyytiälä during day-time. As these highly oxidized organics are roughly 3 times heavier, likely with extremely low vapor pressures, their role in the initial steps of new aerosol particle formation and

  14. Gas phase formation of extremely oxidized pinene reaction products in chamber and ambient air

    NASA Astrophysics Data System (ADS)

    Ehn, M.; Kleist, E.; Junninen, H.; Petäjä, T.; Lönn, G.; Schobesberger, S.; Dal Maso, M.; Trimborn, A.; Kulmala, M.; Worsnop, D. R.; Wahner, A.; Wildt, J.; Mentel, Th. F.

    2012-02-01

    High molecular weight (300-650 Da) naturally charged negative ions have previously been observed at a boreal forest site in Hyytiälä, Finland. The long-term measurements conducted in this work showed that these ions are observed practically every night during spring and summer in Hyytiälä. The ambient mass spectral patterns could be reproduced in striking detail during additional measurements of α-pinene (C10H16) oxidation at low-OH conditions in the Jülich Plant Atmosphere Chamber (JPAC). The ions were identified as clusters of the nitrate ion (NO3-) and α-pinene oxidation products reaching oxygen to carbon ratios of 0.7-1.3, while retaining most of the initial ten carbon atoms. Attributing the ions to clusters instead of single molecules was based on additional observations of the same extremely oxidized organics in clusters with HSO4- (Hyytiälä) and C3F5O2- (JPAC). The most abundant products in the ion spectra were identified as C105H14O7, C10H14O9, C10H16O9, and C10H14O11. The mechanism responsible for forming these molecules is still not clear, but the initial reaction is most likely ozone attack at the double bond, as the ions are mainly observed under dark conditions. β-pinene also formed highly oxidized products under the same conditions, but less efficiently, and mainly C9 compounds which were not observed in Hyytiälä, where β-pinene on average is 4-5 times less abundant than α-pinene. Further, to explain the high O/C together with the relatively high H/C, we propose that geminal diols and/or hydroperoxide groups may be important. We estimate that the night-time concentration of the sum of the neutral extremely oxidized products is on the order of 0.1-1 ppt (~106-107 molec cm-3). This is in a similar range as the amount of gaseous H2SO4 in Hyytiälä during day-time. As these highly oxidized organics are roughly 3 times heavier, likely with extremely low vapor pressures, their role in the initial steps of new aerosol particle formation and

  15. A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1. Volume 1, Overview

    SciTech Connect

    Overbey, W.K. Jr.; Reeves, T.K.; Salamy, S.P.; Locke, C.D.; Johnson, H.R.; Brunk, R.; Hawkins, L.

    1991-05-01

    This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The research has been conducted by Beckley College, Inc. (Beckley) and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center. Phase 1 of the project consisted of compiling and analyzing relevant geological and gas production information in selected areas of Raleigh County, West Virginia, ultimately narrowed to the Eccles, West Virginia, 7 {1/2} minute Quadrangle. The Phase 1 analysis identified key parameters contributing to the accumulation and production of natural gas in Raleigh County, developed analog models relating geological factors to gas production, and identified specific sites to test and verify the analysis methodologies by drilling. Based on the Phase 1 analysis, five sites have been identified with high potential for economic gas production. Phase 2 will consist of drilling, completing, and producing one or more wells at the sites identified in the Phase 1 analyses. The initial well is schedules to the drilled in April 1991. This report summarizes the results of the Phase 1 investigations. For clarity, the report has been prepared in two volumes. Volume 1 presents the Phase 1 overview; Volume 2 contains the detailed geological and production information collected and analyzed for this study.

  16. Kinetics and Product Yields of the Gas-Phase Reactions of Isoprene Hydroxynitrates and Isoprene Carbonynitrates

    NASA Astrophysics Data System (ADS)

    Abdelhamid, A.; Addala, R.; Vizenor, N.; Scruggs, A.; Tyndall, G. S.; Orlando, J. J.; Le, T.; Cardenas, E.; Maitra, S.; Hasson, A. S.

    2013-12-01

    Isoprene nitrates are formed in the troposphere from the reactions of isoprene with OH in the presence of NOx during the day and with NO3 during the night. Depending on their subsequent reactions, these compounds may be reservoirs or sinks for NOx, and may contribute to secondary organic aerosol formation. In this work, two isoprene hydroxynitrates (CH2=CHC(ONO2)(CH3)CH2OH, 1,2-IHN and CH2OHCH(ONO2)C(CH3)=CH2, 4,3-IHN ) and one isoprene carbonyl nitrate (CH2=CHC(ONO2)(CH3)CHO, ICN)) were synthesized. The kinetics and product yields from their reaction with O3, OH, NO3 and Cl were then investigated in a photochemical reactor using a combination of long-path Fourier transform infra-red spectroscopy, proton transfer reaction mass spectrometry and gas chromatography with flame ionization detection. Measured rate coefficients are consistent with reaction with OH and NO3 as the major chemical sinks for these compounds. Measured product yields imply that NOx is not released from these compounds in their reactions with atmospheric oxidants.

  17. City of North Bonneville, Washington: Geothermal Exploration Project, production test well, Phase II. Final report

    SciTech Connect

    Not Available

    1982-06-01

    Based on discussions with the City of North Bonneville, the production test well was drilled to a depth that would also explore for ground water temperatures near 130/sup 0/F (54.4/sup 0/C). Depth projections to a 130/sup 0/F bottom hole temperature were made by assuming a constant ground water temperature rise greater than 50/sup 0/C per kilometer, and by assuming that essentially homogeneous or equivalent conductive rock units would be encountered. Minimum water production requirements were not set, although the City determined that about 800 gpm would be acceptable. Large upper casing diameters of 16 and 12 inches were installed in order to provide the future use of either a vertical turbine or submersible pump, as desired by the city. The scope of work included interpretation of well characteristics, evaluation of ground water as a geothermal resource, geologic analysis of data from drilling and testing, drilling supervision, daily drilling cost accounting, and preparation of a final report. The report includes geologic evaluation of the drilling and test data, ground water and geothermal potential.

  18. Biogas production from anaerobic co-digestion of food waste with dairy manure in a two-phase digestion system.

    PubMed

    Li, Rongping; Chen, Shulin; Li, Xiujiu

    2010-01-01

    Co-digestion of food waste and dairy manure in a two-phase digestion system was conducted in laboratory scale. Four influents of R0, R1, R2, and R3 were tested, which were made by mixing food waste with dairy manure at different ratios of 0:1, 1:1, 3:1, and 6:1, respectively. For each influent, three runs of experiments were performed with the same overall hydraulic retention time (HRT) of 13 days but different HRT for acidification (1, 2, and 3 days) and methanogenesis (12, 11, and 10 days) in two-phase digesters. The results showed that the gas production rate (GPR) of co-digestion of food waste with dairy manure was enhanced by 0.8-5.5 times as compared to the digestion with dairy manure alone. Appropriate HRT for acidification was mainly determined by the biodegradability of the substrate digested. Three-, 2-, and 1-day HRT for acidification were found to be optimal for the digestion of R0, R1, and R2/R3, respectively, when overall HRT of 13 days was used. The highest GPR of 3.97 L/L.day was achieved for R3(6:1) in Run 1 (1 + 12 days), therefore, the mixing ratio of 6:1 and HRT of 1 day for acidification were considered to be the optimal ones and thus recommended for co-digestion of food waste and dairy manure. There were close correlations between degradation of organic matters and GPR. The highest VS removal rate was achieved at the same HRT for acidification and mixing ratio of food waste and dairy manure as GPR in the co-digestion. The two-phase digestion system showed good stability, which was mainly attributed to the strong buffering capacity with two-phase system and the high alkalinity from dairy manure when co-digested with food waste. PMID:19214795

  19. Maggot excretion products from the blowfly Lucilia sericata contain contact phase/intrinsic pathway-like proteases with procoagulant functions.

    PubMed

    Kahl, M; Gökçen, A; Fischer, S; Bäumer, M; Wiesner, J; Lochnit, G; Wygrecka, M; Vilcinskas, A; Preissner, K T

    2015-08-01

    For centuries, maggots have been used for the treatment of wounds by a variety of ancient cultures, as part of their traditional medicine. With increasing appearance of antimicrobial resistance and in association with diabetic ulcers, maggot therapy was revisited in the 1980s. Three mechanisms by which sterile maggots of the green bottle fly Lucilia sericata may improve healing of chronic wounds have been proposed: Biosurgical debridement, disinfecting properties, and stimulation of the wound healing process. However, the influence of maggot excretion products (MEP) on blood coagulation as part of the wound healing process has not been studied in detail. Here, we demonstrate that specific MEP-derived serine proteases from Lucilia sericata induce clotting of human plasma and whole blood, particularly by activating contact phase proteins factor XII and kininogen as well as factor IX, thereby providing kallikrein-bypassing and factor XIa-like activities, both in plasma and in isolated systems. In plasma samples deficient in contact phase proteins, MEP restored full clotting activity, whereas in plasma deficient in either factor VII, IX, X or II no effect was seen. The observed procoagulant/intrinsic pathway-like activity was mediated by (chymo-) trypsin-like proteases in total MEP, which were significantly blocked by C1-esterase inhibitor or other contact phase-specific protease inhibitors. No significant influence of MEP on platelet activation or fibrinolysis was noted. Together, MEP provides contact phase bypassing procoagulant activity and thereby induces blood clotting in the context of wound healing. Further characterisation of the active serine protease(s) may offer new perspectives for biosurgical treatment of chronic wounds. PMID:25948398

  20. Aqueous polymer two-phase systems formed by new thermoseparating polymers.

    PubMed

    Persson, J; Johansson, H O; Galaev, I; Mattiasson, B; Tjerneld, F

    2000-01-01

    A set of new polymers that can be used as phase forming components in aqueous two-phase systems is presented. All polymers studied have thermoseparating properties i.e. form one separate polymer enriched phase and one aqueous solution when heated above the critical temperature. This property makes the polymers attractive alternatives to the polymers used in traditional aqueous two-phase systems such as poly(ethylene glycol) (PEG) and dextran. The thermal phase separation simplifies recycling of the polymers, thus making the aqueous two-phase systems more cost efficient and suitable for use in large scale. Thermoseparating polymers studied have been copolymers of ethylene oxide and propylene oxide (EO-PO), poly (N-isopropylacrylamide) (poly-NIPAM), poly vinyl caprolactam (poly-VCL) and copolymers of N-isopropylacrylamide and vinyl caprolactam with vinyl imidazole (poly(NIPAM-VI) and poly(VCL-VI), respectively). In addition, the copolymer poly(NIPAM-VI) has the property to be uncharged at pH above 7.0 and positively charged at lower pH. This allows the partitioning of protein to be directed by changing the pH in the system instead of the traditional addition of salt to direct the partitioning. Hydrophobically modified EO-PO copolymer (HM-(EO-PO)) with alkyl groups (C14) at both ends forms two-phase system with for example poly(NIPAM-VI). The phase diagram for poly(NIPAM-VI)/HM-(EO-PO) was determined and the model proteins lysozyme and BSA were partitioned in this system. For BSA in poly(NIPAM-VI)/HM-(EO-PO) system a change in pH from 8.0 to 5.4 results in a change of partition coefficient from K = 0.8 to K = 5.1, i.e. BSA could be transferred from the HM-(EO-PO) phase to the poly(NIPAM-VI) phase. BSA partitioning in poly(NIPAM-VI)/HM-(EO-PO) system allows quantitative BSA recovery, and recoveries of poly(NIPAM-VI) and HM-(EO-PO) were 53% and 92%, respectively, after the thermoseparation step. PMID:10892544

  1. Ethanol production via fungal decomposition and fermentation of biomass, Phase 1. Progress report, FY 1980

    SciTech Connect

    Antonopoulos, A.A.; Wene, E.G.

    1980-09-01

    This work was motivated by recorded evidence that Fusarium strains decompose cellulose, hemicelluloses, pectic substances, and lignin, and also ferment both pentoses and hexoses to ethanol. During FY 1980, research efforts in this program's Phase I focused on: (a) collecting and reviewing relevant bibliographic materials for a forthcoming publication; (b) isolating, culturing, and maintaining Fusarium, Trichoderma, and actinomycetous strains for biochemical screening and evaluation; (c) manipulating the genetic constitution of promising Fusarium strains to develop more effective strains for the decomposition and fermentation of biomass; (d) screening for potentially cellulolytic Fusarium and Trichoderma strains; (e) searching for lignolytic and hemicellulolytic Fusarium strains; and (f) screening for effective pentose- and hexose-fermenting Fusarium strains. By September 1980, more than 500 Fusarium strains and about 150 Trichoderma strains had been isolated and screened; all showed cellulolytic activity, with forty-five of the Fusarium strains being exceptionally potent. Several Fusarium strains grown on xylan show a dimorphism (formation of fusoid cells) that may increase their fermenting ability. Several isolated Fusarium strains were active in fermenting pentose and hexose.

  2. Mineral phases and metals in baghouse dust from secondary aluminum production.

    PubMed

    Huang, Xiao-Lan; El Badawy, Amro M; Arambewela, Mahendranath; Adkins, Renata; Tolaymat, Thabet

    2015-09-01

    Baghouse dust (BHD) is a solid waste generated by air pollution control systems during secondary aluminum processing (SAP). Management and disposal of BHD can be challenging in the U.S. and elsewhere. In this study, the mineral phases, metal content and metal leachability of 78 BHD samples collected from 13 different SAP facilities across the U.S. were investigated. The XRD semi-quantitative analysis of BHD samples suggests the presence of metallic aluminum, aluminum oxide, aluminum nitride and its oxides, spinel, elpasolite as well as diaspora. BHD also contains halite, sylvite and fluorite, which are used as fluxes in SAP activities. Total aluminum (Al) in the BHD samples averaged 18% by weight. Elevated concentrations of trace metals (>100 μg L(-1) As; >1000 μg L(-1) Cu, Mn, Se, Pb, Mn and Zn) were also detected in the leachate. The U.S. toxicity characteristic leaching procedure (TCLP) results showed that some samples leached above the toxicity limit for Cd, Pb and Se. Exceeding the TCLP limits in all sample is independent of facilities generating the BHD. From the metal content perspective only, it appears that BHD has a higher potential to exhibit toxicity characteristics than salt cake (the largest waste stream generated by SAP facilities). PMID:25898346

  3. Characterization of U(VI)-phases in corroded cement products by micro(μ)-spectroscopic methods

    NASA Astrophysics Data System (ADS)

    Rothe, J.; Brendebach, B.; Bube, C.; Dardenne, K.; Denecke, M. A.; Kienzler, B.; Metz, V.; Prüßmann, T.; Rickers-Appel, K.; Schild, D.; Soballa, E.; Vitova, T.

    2013-04-01

    Cementation is an industrial scale conditioning method applied to fix and solidify liquid low and intermediate level radioactive wastes (LLW/ILW) prior to underground disposal in geological formations.To assist prognosis of the long-term safety of cemented waste, alteration of uranium doped cement productswas studied in chloride-rich solutions relevant for final LLW/ILW disposal in rock salt. After long-time exposure of the full-scale LLW/ILW simulates to concentrated NaCl and MgCl2 brines, solid samples were retrieved for chemical and mineralogical analysis with an emphasis on uranium speciation in the corroded cement matrix.Bulk and recent spatially resolved micro(μ) U L3-XAFS measurements point to the occurrence of a diuranate type U(VI) phase forming throughout the corroded cement monoliths. U-enriched hot spots with dimensions up to several tens of μm turn out to be generally X-ray amorphous.

  4. Production, Organic Characterization, and Phase Transformations of Marine Particles Aerosolized from a Laboratory Mesocosm Phytoplankton Bioreactor

    NASA Astrophysics Data System (ADS)

    Alpert, P. A.; Knopf, D. A.; Aller, J. Y.; Radway, J.; Kilthau, W.

    2012-12-01

    Previous studies have shown that particles emitted from bubble bursting and wave breaking of ocean waters with high biological activity can contain sea salts associated with organic material, with smaller particles containing a larger mass fraction of organics than larger particles. This likely indicates a link between phytoplankton productivity in oceans and particulate organic material in marine air. Once aerosolized, particles with significant amount of organic material can affect cloud activation and formation of ice crystals, among other atmospheric processes, thus influencing climate. This is significant for clouds and climate particularly over nutrient rich polar seas, in which concentrations of biological organisms can reach up to 109 cells per ml during spring phytoplankton blooms. Here we present results of bubble bursting aerosol production from a seawater mesocosm containing artificial seawater, natural seawater and unialgal cultures of three representative phytoplankton species. These phytoplankton (Thalassiosira pseudonana, Emilianaia huxleyi, and Nannochloris atomus), possessed siliceous frustules, calcareous frustules and no frustules, respectively. Bubbles were generated employing recirculating impinging water jets or glass frits. Dry and humidified aerosol size distributions and bulk aerosol organic composition were measured as a function of phytoplankton growth, and chlorophyll composition and particulate and dissolved organic carbon in the water were determined. Finally, particles were collected on substrates for ice nucleation and water uptake experiments, their elemental compositions were determined using computer controlled scanning electron microscopy and energy dispersive analysis of X-rays (CCSEMEDAX), and their carbon speciation was determined using scanning transmission X-ray microscopy and near-edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). Particle size distributions exposed to dry and humidified air employing

  5. Evaluation of selected chemical processes for production of low-cost silicon, phase 3

    NASA Technical Reports Server (NTRS)

    Blocher, J. M., Jr.; Browning, M. F.; Seifert, D. A.

    1981-01-01

    A Process Development Unit (PDU), which consisted of the four major units of the process, was designed, installed, and experimentally operated. The PDU was sized to 50MT/Yr. The deposition took place in a fluidized bed reactor. As a consequences of the experiments, improvements in the design an operation of these units were undertaken and their experimental limitations were partially established. A parallel program of experimental work demonstrated that Zinc can be vaporized for introduction into the fluidized bed reactor, by direct induction-coupled r.f. energy. Residual zinc in the product can be removed by heat treatment below the melting point of silicon. Current efficiencies of 94 percent and above, and power efficiencies around 40 percent are achievable in the laboratory-scale electrolysis of ZnCl2.

  6. Evaluation of selected chemical processes for production of low-cost silicon, phases 1 and 2

    NASA Technical Reports Server (NTRS)

    Blocher, J. M.; Browning, M. F.

    1978-01-01

    A miniplant, consisting of a 5 cm-diameter fluidized-bed reactor and associated equipment was used to study the deposition parameters, temperature, reactant composition, seed particle size, bed depth, reactant throughput, and methods of reactant introduction. It was confirmed that the permissible range of fluidized-bed temperature was limited at the lower end by zinc condensation (918 C) and at higher temperatures by rapidly decreasing conversion efficiency. Use of a graded bed temperature was shown to increase the conversion efficiency over that obtained in an isothermal bed. Other aspects of the process such as the condensation and fused-salt electrolysis of the ZnCl2 by-product for recycle of zinc and chlorine were studied to provide information required for design of a 50 MT/year experimental facility. In view of the favorable technical and economic indications obtained, it was recommended that construction and operation of the 50 MT/year experimental facility be implemented.

  7. Evaluation of selected chemical processes for production of low-cost silicon, phase 3

    NASA Astrophysics Data System (ADS)

    Blocher, J. M., Jr.; Browning, M. F.; Seifert, D. A.

    1981-03-01

    A Process Development Unit (PDU), which consisted of the four major units of the process, was designed, installed, and experimentally operated. The PDU was sized to 50MT/Yr. The deposition took place in a fluidized bed reactor. As a consequences of the experiments, improvements in the design an operation of these units were undertaken and their experimental limitations were partially established. A parallel program of experimental work demonstrated that Zinc can be vaporized for introduction into the fluidized bed reactor, by direct induction-coupled r.f. energy. Residual zinc in the product can be removed by heat treatment below the melting point of silicon. Current efficiencies of 94 percent and above, and power efficiencies around 40 percent are achievable in the laboratory-scale electrolysis of ZnCl2.

  8. Statistical modeling of phenological phases in Poland based on coupling satellite derived products and gridded meteorological data

    NASA Astrophysics Data System (ADS)

    Czernecki, Bartosz; Jabłońska, Katarzyna; Nowosad, Jakub

    2016-04-01

    The aim of the study was to create and evaluate different statistical models for reconstructing and predicting selected phenological phases. This issue is of particular importance in Poland where national-wide phenological monitoring was abandoned in the middle of 1990s and the reactivated network was established in 2006. Authors decided to evaluate possibilities of using a wide-range of statistical modeling techniques to create synthetic archive dataset. Additionally, a robust tool for predicting the most distinguishable phenophases using only free of charge data as predictors was created. Study period covers the years 2007-2014 and contains only quality-controlled dataset of 10 species and 14 phenophases. Phenological data used in this study originates from the manual observations network run by the Institute of Meteorology and Water Management - National Research Institute (IMGW-PIB). Three kind of data sources were used as predictors: (i) satellite derived products, (ii) preprocessed gridded meteorological data, and (iii) spatial properties (longitude, latitude, altitude) of the monitoring site. Moderate-Resolution Imaging Spectroradiometer (MODIS) level-3 vegetation products were used for detecting onset dates of particular phenophases. Following indices were used: Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), Leaf Area Index (LAI), and Fraction of Photosynthetically Active Radiation (fPAR). Additionally, Interactive Multisensor Snow and Ice Mapping System (IMS) products were chosen to detect occurrence of snow cover. Due to highly noisy data, authors decided to take into account pixel reliability information. Besides satellite derived products (NDVI, EVI, FPAR, LAI, Snow cover), a wide group of observational data and agrometeorological indices derived from the European Climate Assessment & Dataset (ECA&D) were used as a potential predictors: cumulative growing degree days (GDD), cumulative growing precipitation days (GPD

  9. Nucleation field and energy product of aligned two-phase magnets -- Progress towards the '1 MJ/m[sup 3]' magnet

    SciTech Connect

    Skomski, R.; Coey, J.M.D. . Dept. of Pure and Applied Physics)

    1993-11-01

    Exchange hardening of nanostructured two-phase systems composed of an aligned hard phase and a soft phase with high magnetization is Investigated using a micromagnetic approach which accounts for interactions between the soft regions. For Sm[sub 2]Fe[sub 17]N[sub 3](2.5nm)/Fe[sub 65]Co[sub 35](9nm) multilayers an energy product as high as 1 MJ/m[sup 3] (120 MGOe) is predicted, with a rare-earth content of only 5wt%. Giant energy products may also be achieved In suitable cellular and disordered structures.

  10. Analysis of malachite green in aquatic products by carbon nanotube-based molecularly imprinted - matrix solid phase dispersion.

    PubMed

    Wang, Yu; Chen, Ligang

    2015-10-01

    A simple method based on matrix solid phase dispersion (MSPD) using molecularly imprinted polymers (MIPs) as sorbents for selective extraction of malachite green (MG) from aquatic products was developed. The MIPs were prepared by using carbon nanotube as support, MG as template, methacrylic acid as functional monomer, ethyleneglycol dimethacrylate as crosslinker and methylene chloride as solvent. The MIPs were characterized by Fourier transform infrared spectrometry and transmission electron microscopy. The isothermal adsorption, kinetics absorption and selective adsorption experiments were carried out. We optimized the extraction conditions as follows: the ratio of MIPs to sample was 2:3, the dispersion time was 15min, washing solvent was 4mL 50% aqueous methanol and elution solvent was 3mL methanol-acetic acid (98: 2, v/v). Once the MSPD process was completed, the MG extracted from aquatic products was determined by high performance liquid chromatography. The detection limit of MG was 0.7μgkg(-1). The relative standard deviations of intra-day and inter-day were obtained in the range of 0.9%-4.7% and 3.4%-9.8%, respectively. In order to evaluate the applicability and reliability of the proposed method, it was applied to determine MG in different aquatic products samples including fish, shrimp, squid and crabs. The satisfied recoveries were in the range of 89.2%-104.6%. The results showed that this method is faster, simpler and makes extraction and purification in the same system. PMID:26319302

  11. An assessment of potential degradation products in the gas-phase reactions of alternative fluorocarbons in the troposphere

    NASA Technical Reports Server (NTRS)

    Niki, Hiromi

    1990-01-01

    Tropospheric chemical transformations of alternative hydrofluorocarbons (HCF's) and hydrochlorofluorocarbons (HCFC's) are governed by hydroxyl radical initiated oxidation processes, which are likely to be analogous to those known for alkanes and chloroalkanes. A schematic diagram is used to illustrate plausible reaction mechanisms for their atmospheric degradation, where R, R', and R'' denote the F- and/or Cl-substituted alkyl groups derived from HCF's and HCFC's subsequent th the initial H atom abstraction by HO radicals. At present, virtually no kinetic data exist for the majority of these reactions, particularly for those involving RO. Potential degradation intermediates and final products include a large variety of fluorine- and/or chlorine-containing carbonyls, acids, peroxy acids, alcohols, hydrogen peroxides, nitrates and peroxy nitrates, as summarized in the attached table. Probably atmospheric lifetimes of these compounds were also estimated. For some carbonyl and nitrate products shown in this table, there seem to be no significant gas-phase removal mechanisms. Further chemical kinetics and photochemical data are needed to quantitatively assess the atmospheric fate of HCF's and HCFC's, and of the degradation products postulated in this report.

  12. Products and mechanisms of the reaction of gas phase ozone with organic colorants

    SciTech Connect

    Grosjean, D. ); Druzik, J.R. ); Sensharma, D.K. ); Whitmore, P.M.; DeMoor, C.P.; Cass, G.R. )

    1988-09-01

    Studies carried out in this laboratory have shown that many artists organic colorants fade substantially when exposed to ozone in the dark. These studies typically involved pigment exposure for 12 weeks to purified air containing 0.3-0.4 ppm of ozone at ambient temperature and humidity. These laboratory conditions are equivalent to about six years of exposure inside a typical air-conditioned building in Los Angeles, and the observed fading is therefore directly relevant to possible damage to works of arts in museum settings. Organic colorants that were most ozone-fugitive included natural colorants, such as curcumin and indigo, as well as modern synthetic colorants such as alizarin lakes and triphenylmethane dyes. Thus, these colorants were selected for further study with emphasis on the nature of the reaction products. Exposures were carried out on different substrates including watercolor paper, cellulose, silica gel, and Teflon. The experiments involved long-term exposure to low levels of ozone (e.g. {approximately} 0.3 ppm for 90 days) or shorter-term exposure to higher ozone concentrations (e.g. 10 ppm for 24 hours). Exposed and control samples, along with solvent and substrate blanks, were analyzed by mass spectrometry using a Kratos Scientific Instruments MS25 hexapole mass spectrometer operated in either methane chemical ionization (CI) or electron impact (EI) modes.

  13. Pixel module production and qualification for the phase I upgrade of CMS

    NASA Astrophysics Data System (ADS)

    Miñano Moya, M.

    2015-01-01

    The instantaneous luminosity of the Large Hadron Collider (LHC) is being increased in several steps over the next 10 years to maximize its discovery potential for new physics. However, at a luminosity of twice the design luminosity of the LHC of 1034 cm-2 s-1, the performance of the current CMS pixel detector is degraded by substantial deadtime caused by the readout chip (ROC). To make full use of the proton-proton collisions being provided by the LHC, CMS will replace its pixel detector during the extended winter shutdown in 2016-2017 with a new detector with four barrel layers and three disks in each endcap. Module production includes bump bonding, wire bonding, and gluing processes, as well as a series of functionality tests, calibrations and thermal cycling. One of the calibration steps is the X-ray calibration, which provides an absolute energy calibration of an internal calibration circuit. This circuit injects charge into the preamplifier to simulate a signal, and is used to define several parameters of the readout chip, including the threshold. Therefore, an absolute calibration is required in order to know the threshold in units of electrons. In this article, the barrel module assembly is explained, with a special focus on the X-ray calibration of the pixel detector.

  14. Consumer-phase Salmonella enterica serovar enteritidis risk assessment for egg-containing food products.

    PubMed

    Mokhtari, Amirhossein; Moore, Christina M; Yang, Hong; Jaykus, Lee-Ann; Morales, Roberta; Cates, Sheryl C; Cowen, Peter

    2006-06-01

    We describe a one-dimensional probabilistic model of the role of domestic food handling behaviors on salmonellosis risk associated with the consumption of eggs and egg-containing foods. Six categories of egg-containing foods were defined based on the amount of egg contained in the food, whether eggs are pooled, and the degree of cooking practiced by consumers. We used bootstrap simulation to quantify uncertainty in risk estimates due to sampling error, and sensitivity analysis to identify key sources of variability and uncertainty in the model. Because of typical model characteristics such as nonlinearity, interaction between inputs, thresholds, and saturation points, Sobol's method, a novel sensitivity analysis approach, was used to identify key sources of variability. Based on the mean probability of illness, examples of foods from the food categories ranked from most to least risk of illness were: (1) home-made salad dressings/ice cream; (2) fried eggs/boiled eggs; (3) omelettes; and (4) baked foods/breads. For food categories that may include uncooked eggs (e.g., home-made salad dressings/ice cream), consumer handling conditions such as storage time and temperature after food preparation were the key sources of variability. In contrast, for food categories associated with undercooked eggs (e.g., fried/soft-boiled eggs), the initial level of Salmonella contamination and the log10 reduction due to cooking were the key sources of variability. Important sources of uncertainty varied with both the risk percentile and the food category under consideration. This work adds to previous risk assessments focused on egg production and storage practices, and provides a science-based approach to inform consumer risk communications regarding safe egg handling practices. PMID:16834632

  15. Production of clinical-grade plasmid DNA for human Phase I clinical trials and large animal clinical studies.

    PubMed

    Przybylowski, Mark; Bartido, Shirley; Borquez-Ojeda, Oriana; Sadelain, Michel; Rivière, Isabelle

    2007-06-28

    The use of plasmid DNA as vaccines for the treatment of cancer and infectious diseases is on the rise. In order to facilitate the manufacture of clinical-grade plasmid DNA for Phase I clinical trials, we developed a process whereby >200 mg plasmid could be produced in a single production run under Good Manufacturing Practices. A dedicated cleanroom (Class 10,000 with Class 100 biosafety cabinet) is utilized for production of the bacterial cell bank, fermentation, harvest/lysis of the biomass, and downstream purification. Fermentation requires three 16-18 h runs (approximately 12 L each) in shaker-flasks, yielding approximately 60 g bacterial paste following batch centrifugation. The biomass is alkaline-lysed, pooled, and the resulting flocculent precipitate is separated by a novel vacuum step, followed by depth-filtration. Downstream processing includes anion-exchange chromatography, utilizing Qiagen silica-based resin, and precipitation with isopropanol. Following precipitation, the DNA is harvested by centrifugation, dried, formulated, and sterile-filtered using a Sartorius Sartobran 150 filter prior to Final-Filling. All processing steps utilize sterilized, single-use components. This process results in a product manufactured according to regulatory guidelines. The plasmid DNA is sterile with >or=95% supercoiled DNA, an A260/A280 ratio>or=1.9, undetectable or extremely low residual endotoxin, RNA, genomic DNA, protein, and antibiotic. Residual solvent levels are negligible. The product yields the predicted profile upon restriction-enzyme digestion, is biologically active upon transfection and remains stable for several years at -20 degrees C. We have therefore developed a reproducible and cost effective process to manufacture clinical-grade plasmid DNA. This process can be adapted by other academic centers for human or large animal clinical trials. PMID:17537555

  16. Combined crystal plasticity and phase-field method for recrystallization in a process chain of sheet metal production

    NASA Astrophysics Data System (ADS)

    Vondrous, Alexander; Bienger, Pierre; Schreijäg, Simone; Selzer, Michael; Schneider, Daniel; Nestler, Britta; Helm, Dirk; Mönig, Reiner

    2015-02-01

    In sheet metal production, a typical process chain contains hot rolling, cold rolling and annealing as a sequence of consecutive processing steps. We investigate the grain structure evolution of body centered cubic low carbon steel and focus on recrystallization, by employing different computational methods which operate across the process chain and across length scales. In particular, we combine finite element crystal plasticity with phase-field simulations to study the effect of deformation of the grain structure by hot and cold rolling on recrystallization during annealing. The overall goal is to represent the most important technological quantities such as texture evolution and the fraction of recrystallization. The results of grain quantities are validated by a comparison of the orientation distribution functions with experimental electron backscatter measurements. The coupling of the simulation methods has shown that the effects of recrystallization can be recovered well, depending on the preceding processing conditions.

  17. Reliability of the Solar One plant during the power production phase: August 1, 1984--July 31, 1987

    SciTech Connect

    Kolb, G.J.; Lopez, C.W.

    1988-10-01

    The power production phase at Solar One spanned three years from August 1, 1984 through July 31, 1987. In that period the plant achieved an average availability, during hours of sunshine, of 81.7%. This report presents the frequencies and causes of the plant outages that occurred. The eleven most important causes composed 75% of the total outage time. Qualitative insights related to the origin and mitigation of these causes are provided. Also presented are insights and statistics regarding the reliability of the heliostat field. The quantitative and qualitative information presented in this report will be useful to studies aimed at improving the reliability of future solar central receiver power plants. 20 refs., 11 figs., 3 tabs.

  18. Heterogeneous oxidation of saturated organic aerosols by hydroxyl radicals: uptake kinetics, condensed-phase products, and particle size change

    NASA Astrophysics Data System (ADS)

    George, I. J.; Vlasenko, A.; Slowik, J. G.; Broekhuizen, K.; Abbatt, J. P. D.

    2007-08-01

    The kinetics and reaction mechanism for the heterogeneous oxidation of saturated organic aerosols by gas-phase OH radicals were investigated under NOx-free conditions. The reaction of 150 nm diameter Bis(2-ethylhexyl) sebacate (BES) particles with OH was studied as a proxy for chemical aging of atmospheric aerosols containing saturated organic matter. An aerosol reactor flow tube combined with an Aerodyne time-of-flight aerosol mass spectrometer (ToF-AMS) and scanning mobility particle sizer (SMPS) was used to study this system. Hydroxyl radicals were produced by 254 nm photolysis of O3 in the presence of water vapour. The kinetics of the heterogeneous oxidation of the BES particles was studied by monitoring the loss of a mass fragment of BES with the ToF-AMS as a function of OH exposure. We measured an initial OH uptake coefficient of γ0=1.3 (±0.4), confirming that this reaction is highly efficient. The density of BES particles increased by up to 20% of the original BES particle density at the highest OH exposure studied, consistent with the particle becoming more oxidized. Electrospray ionization mass spectrometry analysis showed that the major particle-phase reaction products are multifunctional carbonyls and alcohols with higher molecular weights than the starting material. Volatilization of oxidation products accounted for a maximum of 17% decrease of the particle volume at the highest OH exposure studied. Tropospheric organic aerosols will become more oxidized from heterogeneous photochemical oxidation, which may affect not only their physical and chemical properties, but also their hygroscopicity and cloud nucleation activity.

  19. Chemical Composition of Gas-Phase Oxidation Products from Biogenic Sources in the Southeast US during SOAS

    NASA Astrophysics Data System (ADS)

    Stark, H.; Massoli, P.; Thompson, S.; Yatavelli, L. R.; Mohr, C.; Brophy, P.; Murschell, T.; Hu, W.; Canagaratna, M.; Krechmer, J.; Junninen, H.; Hakala, J. P.; Day, D. A.; Campuzano Jost, P.; Palm, B. B.; Ortega, A. M.; Kimmel, J.; Cubison, M.; Lopez-Hilfiker, F.; Thornton, J. A.; Baumann, K.; Edgerton, E.; Farmer, D.; Jimenez, J. L.; Jayne, J. T.; Worsnop, D. R.

    2013-12-01

    Reduced species emitted to the atmosphere are chemically transformed by atmospheric oxidants. The measurement of the large number of resulting oxidized compounds is crucial to understand and quantify these transformation processes. We analyzed datasets from four high-resolution time-of-flight chemical ionization mass spectrometers (HRToF-CIMS) during the Southern Oxidant and Aerosol Study (SOAS) in June and July 2013 at the Alabama Supersite in the Southeast U.S. These datasets allow specification and quantification of the multiple gas-phase compounds produced by chemical oxidation. The mass spectrometers used different reagent ions, nitrate (NO3-), acetate (CH3COO-), and iodide (I-). In this study, we will present the chemical composition of isoprene and terpene oxidation products as measured by the different techniques. When comparing the concentration and composition at different conditions (e.g., time of day, NOx levels, aerosol loading, RH), differences in gas-phase composition provide indications of both the changes in chemical processing arising from the different conditions as well as different sensitivities of the reagent ions. We will discuss these differences in terms of bulk chemical parameters such as carbon oxidation state, carbon number and oxygen-to-carbon ratio.

  20. "Brief report: increase in production of spoken words in some children with autism after PECS teaching to Phase III".

    PubMed

    Carr, Deborah; Felce, Janet

    2007-04-01

    The context for this work was an evaluation study [Carr, D., & Felce, J. A. (in press)] of the early phases of the Picture Exchange Communication System (PECS) [Frost, L. A., & Bondy, A. S. (1994). The picture exchange communication system training manual. Cherry Hill, NJ: Pyramid Educational Consultants, Inc.; Frost, L. A., & Bondy, A. S. (2004). The picture exchange communication system training manual, 2nd edn. Newark, DE: Pyramid Educational Consultants, Inc.]. This paper reports that five of 24 children who received 15 h of PECS teaching towards Phase III over a period of 4-5 weeks, showed concomitant increases in speech production, either in initiating communication with staff or in responding, or both. No children in the PECS group demonstrated a decrease in spoken words after receiving PECS teaching. In the control group, only one of 17 children demonstrated a minimal increase and four of 17 children demonstrated a decrease in use of spoken words after a similar period without PECS teaching. PMID:17048094

  1. Biological treatment of two-phase olive mill wastewater (TPOMW, alpeorujo): polyhydroxyalkanoates (PHAs) production by Azotobacter strains.

    PubMed

    Cerrone, Federico; Sánchez-Peinado, Maria del Mar; Juárez-Jimenez, Belén; González-López, Jesús; Pozo, Clementina

    2010-03-01

    Azotobacter chroococcum H23 (CECT 4435), Azotobacter vinelandii UWD, and Azotobacter vinelandii (ATCC 12837), members of the family Pseudomonadaceae, were used to evaluate their capacity to grow and accumulate polyhydroxyalkanoates (PHAs) using two-phase olive mill wastewater (TPOMW, alpeorujo) diluted at different concentrations as the sole carbon source. The PHAs amounts (g/l) increased clearly when the TPOMW samples were previously digested under anaerobic conditions. The MNR analysis demonstrated that the bacterial strains formed only homopolymers containing beta-hydroxybutyrate, either when grown in diluted TPOMW medium or diluted anaerobically digested TPOMW medium. COD values of the diluted anaerobically digested waste were measured before and after the aerobic PHA-storing phase, and a clear reduction (72%) was recorded after 72 h of incubation. The results obtained in this study suggest the perspectives for using these bacterial strains to produce PHAs from TPOMW, and in parallel, contribute efficiently to the bioremediation of this waste. This fact seems essential if bioplastics are to become competitive products. PMID:20372033

  2. Dynamic fabric phase sorptive extraction for a group of pharmaceuticals and personal care products from environmental waters.

    PubMed

    Lakade, Sameer S; Borrull, Francesc; Furton, Kenneth G; Kabir, Abuzar; Marcé, Rosa Maria; Fontanals, Núria

    2016-07-22

    This paper describes for the first time the use of a new extraction technique, based on fabric phase sorptive extraction (FPSE). This new mode proposes the extraction of the analytes in dynamic mode in order to reduce the extraction time. Dynamic fabric phase sorptive extraction (DFPSE) followed by liquid chromatography-tandem mass spectrometry was evaluated for the extraction of a group of pharmaceuticals and personal care products (PPCPs) from environmental water samples. Different parameters affecting the extraction were optimized and best conditions were achieved when 50mL of sample at pH 3 was passed through 3 disks and analytes retained were eluted with 10mL of ethyl acetate. The recoveries were higher than 60% for most of compounds with the exception of the most polar ones (between 8% and 38%). The analytical method was validated with environmental samples such as river water and effluent and influent wastewater, and good performance was obtained. The analysis of samples revealed the presence of some PPCPs at low ngL(-1) concentrations. PMID:27295962

  3. Gas-phase production of single-walled carbon nanotubes from carbon monoxide: a review of the hipco process.

    PubMed

    Nikolaev, Pavel

    2004-04-01

    The latest process for producing large quantities of single-walled carbon nanotubes (SWNTs) to emerge from the Rice University, dubbed HiPco, is living up to its promise. The current production rates approach 450 mg/h (or 10 g/day), and nanotubes typically have no more than 7 mol % of iron impurities. Second-generation HiPco apparatus can run continuously for 7-10 days at a time. In the HiPco process nanotubes grow in high-pressure, high-temperature flowing CO on catalytic clusters of iron. Catalyst is formed in situ by thermal decomposition of iron pentacarbonyl, which is delivered intact within a cold CO flow and then rapidly mixed with hot CO in the reaction zone. Upon heating, the Fe(CO)5 decomposes into atoms that condense into larger clusters. SWNTs nucleate and grow on these particles in the gas phase via CO disproportionation: CO + CO --> CO2 + C (SWNT), catalyzed by the Fe surface. The concentration of CO2 produced in this reaction is equal to that of carbon and can therefore serve as a useful real-time feedback parameter. It was used to study and optimize SWNT production as a function of temperature, pressure, and Fe(CO)5 concentration. The results of the parametric study are in agreement with current understanding of the nanotube formation mechanism. PMID:15296221

  4. Gas-phase production of single-walled carbon nanotubes from carbon monoxide: a review of the hipco process

    NASA Technical Reports Server (NTRS)

    Nikolaev, Pavel

    2004-01-01

    The latest process for producing large quantities of single-walled carbon nanotubes (SWNTs) to emerge from the Rice University, dubbed HiPco, is living up to its promise. The current production rates approach 450 mg/h (or 10 g/day), and nanotubes typically have no more than 7 mol % of iron impurities. Second-generation HiPco apparatus can run continuously for 7-10 days at a time. In the HiPco process nanotubes grow in high-pressure, high-temperature flowing CO on catalytic clusters of iron. Catalyst is formed in situ by thermal decomposition of iron pentacarbonyl, which is delivered intact within a cold CO flow and then rapidly mixed with hot CO in the reaction zone. Upon heating, the Fe(CO)5 decomposes into atoms that condense into larger clusters. SWNTs nucleate and grow on these particles in the gas phase via CO disproportionation: CO + CO --> CO2 + C (SWNT), catalyzed by the Fe surface. The concentration of CO2 produced in this reaction is equal to that of carbon and can therefore serve as a useful real-time feedback parameter. It was used to study and optimize SWNT production as a function of temperature, pressure, and Fe(CO)5 concentration. The results of the parametric study are in agreement with current understanding of the nanotube formation mechanism.

  5. Singular Values for Products of Complex Ginibre Matrices with a Source: Hard Edge Limit and Phase Transition

    NASA Astrophysics Data System (ADS)

    Forrester, Peter J.; Liu, Dang-Zheng

    2016-05-01

    The singular values squared of the random matrix product {Y = {Gr G_{r-1}} ldots G1 (G0 + A)}, where each {Gj} is a rectangular standard complex Gaussian matrix while A is non-random, are shown to be a determinantal point process with the correlation kernel given by a double contour integral. When all but finitely many eigenvalues of A* A are equal to bN, the kernel is shown to admit a well-defined hard edge scaling, in which case a critical value is established and a phase transition phenomenon is observed. More specifically, the limiting kernel in the subcritical regime of {0 < b < 1} is independent of b, and is in fact the same as that known for the case b = 0 due to Kuijlaars and Zhang. The critical regime of b = 1 allows for a double scaling limit by choosing {{b = (1 - τ/√{N})^{-1}}}, and for this the critical kernel and outlier phenomenon are established. In the simplest case r = 0, which is closely related to non-intersecting squared Bessel paths, a distribution corresponding to the finite shifted mean LUE is proven to be the scaling limit in the supercritical regime of {b > 1} with two distinct scaling rates. Similar results also hold true for the random matrix product {Tr T_{r-1} ldots T1 (G0 + A)}, with each {Tj} being a truncated unitary matrix.

  6. An investigation of low ergonomics risk awareness, among staffs at early product development phase in Malaysia automotive industries

    NASA Astrophysics Data System (ADS)

    Aziz, Fazilah Abdul; Razali, Noraini; Najmiyah Jaafar, Nur

    2016-02-01

    Currently there are many automotive companies still unable to effectively prevent consequences of poor ergonomics in their manufacturing processes. This study purpose is to determine the surrounding factors that influence low ergonomics risk awareness among staffs at early product development phase in Malaysia automotive industry. In this study there are four variables, low ergonomic risk awareness, inappropriate method and tools, tight development schedule and lack of management support. The survey data were gathered from 245 respondents of local automotive companies in Malaysia. The data was analysed through multiple regression and moderated regression using the IBM SPSS software. Study results revealed that low ergonomic risk awareness has influenced by inappropriate method and tool, and tight development schedule. There were positive linear relationships between low ergonomic risk awareness and inappropriate method and tools, and tight development schedule. The more inappropriate method and tools applied; the lower their ergonomic risk awareness. The more tight development schedule is the lower ergonomic risk awareness. The relationship between low ergonomic risk awareness and inappropriate method and tools depends on staff's age, and education level. Furthermore the relationship between low ergonomic risk awareness and tight development schedule depends on staff's working experience and number of project involvement. The main contribution of this paper was identified the number of factors of low ergonomics risk awareness and offers better understanding on ergonomics among researchers and automotive manufacturer's employees during product development process.

  7. 30 CFR 203.34 - To which production may an RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... perforated deeper than 15,000 feet TVD SS; (b) To production from a deep well or ultra-deep well on any other... condensate) volumes; or (d) To production from a deep well or ultra-deep well that commenced drilling before... 30 Mineral Resources 2 2012-07-01 2012-07-01 false To which production may an RSV earned...

  8. 30 CFR 203.34 - To which production may an RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... perforated deeper than 15,000 feet TVD SS; (b) To production from a deep well or ultra-deep well on any other... condensate) volumes; or (d) To production from a deep well or ultra-deep well that commenced drilling before... 30 Mineral Resources 2 2014-07-01 2014-07-01 false To which production may an RSV earned...

  9. 30 CFR 203.33 - To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... lease under 30 CFR 1210.102. All gas production from qualified wells reported on the OGOR-A, including... produces 18 BCF, and the qualified well on lease B produces 37 BCF, then the production volume from and... 30 Mineral Resources 2 2014-07-01 2014-07-01 false To which production do I apply the RSV...

  10. 30 CFR 203.34 - To which production may an RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... feet TVD SS; (b) To production from a deep well or ultra-deep well on any other lease, except as...) To production from a deep well or ultra-deep well that commenced drilling before: (1) March 26, 2003... 30 Mineral Resources 2 2010-07-01 2010-07-01 false To which production may an RSV earned...

  11. 30 CFR 203.34 - To which production may an RSV earned by qualified phase 2 and phase 3 ultra-deep wells on my...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... perforated deeper than 15,000 feet TVD SS; (b) To production from a deep well or ultra-deep well on any other... condensate) volumes; or (d) To production from a deep well or ultra-deep well that commenced drilling before... 30 Mineral Resources 2 2011-07-01 2011-07-01 false To which production may an RSV earned...

  12. 30 CFR 203.33 - To which production do I apply the RSV earned by qualified phase 2 and phase 3 ultra-deep wells...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... lease under 30 CFR 1210.102. All gas production from qualified wells reported on the OGOR-A, including... produces 18 BCF, and the qualified well on lease B produces 37 BCF, then the production volume from and... 30 Mineral Resources 2 2012-07-01 2012-07-01 false To which production do I apply the RSV...

  13. Integrated two-liquid phase bioconversion and product-recovery processes for the oxidation of alkanes: Process design and economic evaluation

    SciTech Connect

    Mathys, R.G.; Schmid, A.; Witholt, B.

    1999-08-20

    Pseudomonas oleovorans and recombinant strains containing the alkane oxidation genes can product alkane oxidation genes can produce alkane oxidation products in two-liquid phase bioreactor systems. In these bioprocesses the cells, which grow in the aqueous phase, oxidize apolar, non-water soluble substrates. The apolar products typically accumulate in the emulsified apolar phase. The authors have studied both the bioconversion systems and several downstream processing systems to separate and purify alkanols from these two-liquid phase media. Based on the information generated in these studies, the authors have now designed bioconversion and downstream processing systems for the production of 1-alkanols from n-alkanes on a 10 kiloton/yr scale, taking the conversion of n-octane to 1-octanol as a model system. Here, the authors describe overall designs of fed-batch and continuous-fermentation processes for the oxidation of octane to 1-octanol by Pseudomonas oleovoran, and the authors discuss the economics of these processes. The overall performance of each of these two systems has been modeled with Aspen software. Although the continuous process is about 10% more expensive than the fed-batch process, improvements to reduce overall cost can be achieved more easily for continuous than for fed-batch fermentation by decreasing the dilution rate while maintaining near constant productivity. Improvements relevant to both processes can be achieved by increasing the biocatalyst performance, which results in improved overall efficiency, decreased capital investment, and hence, decreased production cost.

  14. Phase 2a Study of Ataluren-Mediated Dystrophin Production in Patients with Nonsense Mutation Duchenne Muscular Dystrophy

    PubMed Central

    Finkel, Richard S.; Flanigan, Kevin M.; Wong, Brenda; Bönnemann, Carsten; Sampson, Jacinda; Sweeney, H. Lee; Reha, Allen; Northcutt, Valerie J.; Elfring, Gary; Barth, Jay; Peltz, Stuart W.

    2013-01-01

    Background Approximately 13% of boys with Duchenne muscular dystrophy (DMD) have a nonsense mutation in the dystrophin gene, resulting in a premature stop codon in the corresponding mRNA and failure to generate a functional protein. Ataluren (PTC124) enables ribosomal readthrough of premature stop codons, leading to production of full-length, functional proteins. Methods This Phase 2a open-label, sequential dose-ranging trial recruited 38 boys with nonsense mutation DMD. The first cohort (n = 6) received ataluren three times per day at morning, midday, and evening doses of 4, 4, and 8 mg/kg; the second cohort (n = 20) was dosed at 10, 10, 20 mg/kg; and the third cohort (n = 12) was dosed at 20, 20, 40 mg/kg. Treatment duration was 28 days. Change in full-length dystrophin expression, as assessed by immunostaining in pre- and post-treatment muscle biopsy specimens, was the primary endpoint. Findings Twenty three of 38 (61%) subjects demonstrated increases in post-treatment dystrophin expression in a quantitative analysis assessing the ratio of dystrophin/spectrin. A qualitative analysis also showed positive changes in dystrophin expression. Expression was not associated with nonsense mutation type or exon location. Ataluren trough plasma concentrations active in the mdx mouse model were consistently achieved at the mid- and high- dose levels in participants. Ataluren was generally well tolerated. Interpretation Ataluren showed activity and safety in this short-term study, supporting evaluation of ataluren 10, 10, 20 mg/kg and 20, 20, 40 mg/kg in a Phase 2b, double-blind, long-term study in nonsense mutation DMD. Trial Registration ClinicalTrials.gov NCT00264888 PMID:24349052

  15. Reservoir analysis study, Naval Petroleum Reserve No. 1, Elk Hills Field, Kern County, California: Phase 3 report, economic development and production plan

    SciTech Connect

    Not Available

    1988-07-01

    Jerry R. Bergeson and Associates, Inc. (Bergeson) has completed Phase 3 of the Reservoir Analysis, Naval Petroleum Reserve Number 1, Elk Hills Oilfield, California. The objective of this phase of the study was to establish the economic potential for the field by determining the optimum economic plan for development and production. The optimum economic plan used net cash flow analysis to evaluate future expected Department of Energy revenues less expenses and investments for proved developed, proved undeveloped, probable, possible and possible-enhanced oil recovery (EOR) reserves assigned in the Phase 2 study. The results of the Phase 2 study were used to define future production flowstreams. Additional production scheduling was carried out to evaluate accelerated depletion of proved developed reserves in the 29R, 31 C/D Shale and Northwest Stevens T Sand/N Shale Reservoirs. Production, cost and investment schedules were developed for the enhanced oil recovery projects identified in Phase 2. Price forecasts were provided by the Department of Energy. Operating costs and investment requirements were estimated by Bergeson. 4 figs., 48 tabs.

  16. Enzymatic hydrolysis of penicillin and in situ product separation in thermally induced reversible phase-separation of ionic liquids/water mixture.

    PubMed

    Mai, Ngoc Lan; Koo, Yoon-Mo

    2014-09-01

    Enzymatic hydrolysis of penicillin G to produce 6-aminopenicillanic acid, key intermediate for the production of semisynthetic β-lactam antibiotics, is one of the most relevant example of industrial implementation of biocatalysts. The hydrolysis reaction is traditionally carried out in aqueous buffer at pH 7.5-8. However, the aqueous rout exhibits several drawbacks in enzyme stability and product recovery. In this study, several ionic liquids (ILs) have been used as media for enzymatic hydrolysis of penicillin G. The results indicated that hydrophobic ILs/water two-phase system were good media for the reaction. In addition, a novel aqueous two-phase system based on the lower critical solution temperature type phase changes of amino acid based ILs/water mixture was developed for in situ penicillin G hydrolysis and product separation. For instance, hydrolysis yield of 87.13% was obtained in system containing 30 wt% [TBP][Tf-ILe] with pH control (pH 7.6). Since the phase-separation of this medium system can be reversible switched from single to two phases by slightly changing the solution temperature, enzymatic hydrolytic reaction and product recovery were more efficient than those of aqueous system. In addition, the ILs could be reused for at least 5 cycles without significant loss in hydrolysis efficiency. PMID:25039057

  17. Aqueous-phase oxidation of green leaf volatiles by hydroxyl radical as a source of SOA: Product identification from methyl jasmonate and methyl salicylate oxidation

    NASA Astrophysics Data System (ADS)

    Hansel, Amie K.; Ehrenhauser, Franz S.; Richards-Henderson, Nicole K.; Anastasio, Cort; Valsaraj, Kalliat T.

    2015-02-01

    Green leaf volatiles (GLVs) are a group of biogenic volatile organic compounds (BVOCs) released into the atmosphere by vegetation. BVOCs produce secondary organic aerosol (SOA) via gas-phase reactions, but little is known of their aqueous-phase oxidation as a source of SOA. GLVs can partition into atmospheric water phases, e.g., fog, mist, dew or rain, and be oxidized by hydroxyl radicals (˙OH). These reactions in the liquid phase also lead to products that have higher molecular weights, increased polarity, and lower vapor pressures, ultimately forming SOA after evaporation of the droplet. To examine this process, we investigated the aqueous, ˙OH-mediated oxidation of methyl jasmonate (MeJa) and methyl salicylate (MeSa), two GLVs that produce aqueous-phase SOA. High performance liquid chromatography/electrospray ionization mass spectrometry (HPLC-ESI-MS) was used to monitor product formation. The oxidation products identified exhibit higher molecular mass than their parent GLV due to either dimerization or the addition of oxygen and hydroxyl functional groups. The proposed structures of potential products are based on mechanistic considerations combined with the HPLC/ESI-MS data. Based on the structures, the vapor pressure and the Henry's law constant were estimated with multiple methods (SPARC, SIMPOL, MPBPVP, Bond and Group Estimations). The estimated vapor pressures of the products identified are significantly (up to 7 orders of magnitude) lower than those of the associated parent compounds, and therefore, the GLV oxidation products may remain as SOA after evaporation of the water droplet. The contribution of the identified oxidation products to SOA formation is estimated based on measured HPLC-ESI/MS responses relative to previous aqueous SOA mass yield measurements.

  18. Biogas production from municipal solid wastes using an integrated rotary drum and anaerobic-phased solids digester system.

    PubMed

    Zhu, Baoning; Zhang, Ruihong; Gikas, Petros; Rapport, Joshua; Jenkins, Bryan; Li, Xiujin

    2010-08-01

    This research was conducted to develop an integrated rotary drum reactor (RDR)-anaerobic-phased solids (APS) digester system for the treatment of municipal solid waste (MSW) to produce biogas energy and achieve waste reduction. A commercial RDR facility was used to provide a 3-d pretreatment and sufficient separation of the organics from MSW and then the organics were digested in a laboratory APS-digester system for biogas production. The organics generated from the RDR contained 50% total solids (TS) and 36% volatile solids (VS) on wet basis. The APS-digester was started at an organic loading rate (OLR) of 3.1 gVS L(-1) d(-1) and operated at three higher OLRs of 4.6, 7.7 and 9.2 gVS L(-1) d(-1). At the OLR of 9.2 gVS L(-1) d(-1) the system biogas production rate was 3.5 L L(-1) d(-1) and the biogas and methane yields were 0.38 and 0.19 L gVS(-1), respectively. Anaerobic digestion resulted in 38% TS reduction and 53% VS reduction in the organic solids. It was found that the total VFA concentration reached a peak value of 15,000 mg L(-1) as acetic acid in the first 3d of batch digestion and later decreased to about 500 mg L(-1). The APS-digester system remained stable at each OLRs for over 100d with the pH in the hydrolysis reactors in the range of 7.3-7.8 and the pH in the biogasification reactor in 7.9-8.1. The residual solids after the digestion had a high heating value of 14.7 kJ gTS(-1). PMID:20409703

  19. Primary gas- and particle-phase emissions and secondary organic aerosol production from gasoline and diesel off-road engines.

    PubMed

    Gordon, Timothy D; Tkacik, Daniel S; Presto, Albert A; Zhang, Mang; Jathar, Shantanu H; Nguyen, Ngoc T; Massetti, John; Truong, Tin; Cicero-Fernandez, Pablo; Maddox, Christine; Rieger, Paul; Chattopadhyay, Sulekha; Maldonado, Hector; Maricq, M Matti; Robinson, Allen L

    2013-12-17

    Dilution and smog chamber experiments were performed to characterize the primary emissions and secondary organic aerosol (SOA) formation from gasoline and diesel small off-road engines (SOREs). These engines are high emitters of primary gas- and particle-phase pollutants relative to their fuel consumption. Two- and 4-stroke gasoline SOREs emit much more (up to 3 orders of magnitude more) nonmethane organic gases (NMOGs), primary PM and organic carbon than newer on-road gasoline vehicles (per kg of fuel burned). The primary emissions from a diesel transportation refrigeration unit were similar to those of older, uncontrolled diesel engines used in on-road vehicles (e.g., premodel year 2007 heavy-duty diesel trucks). Two-strokes emitted the largest fractional (and absolute) amount of SOA precursors compared to diesel and 4-stroke gasoline SOREs; however, 35-80% of the NMOG emissions from the engines could not be speciated using traditional gas chromatography or high-performance liquid chromatography. After 3 h of photo-oxidation in a smog chamber, dilute emissions from both 2- and 4-stroke gasoline SOREs produced large amounts of semivolatile SOA. The effective SOA yield (defined as the ratio of SOA mass to estimated mass of reacted precursors) was 2-4% for 2- and 4-stroke SOREs, which is comparable to yields from dilute exhaust from older passenger cars and unburned gasoline. This suggests that much of the SOA production was due to unburned fuel and/or lubrication oil. The total PM contribution of different mobile source categories to the ambient PM burden was calculated by combining primary emission, SOA production and fuel consumption data. Relative to their fuel consumption, SOREs are disproportionately high total PM sources; however, the vastly greater fuel consumption of on-road vehicles renders them (on-road vehicles) the dominant mobile source of ambient PM in the Los Angeles area. PMID:24261886

  20. Depsidones from Lichens as Natural Product Inhibitors of M-Phase Phosphoprotein 1, a Human Kinesin Required for Cytokinesis.

    PubMed

    Talapatra, Sandeep K; Rath, Oliver; Clayton, Eddie; Tomasi, Sophie; Kozielski, Frank

    2016-06-24

    M-Phase Phosphoprotein 1 (MPP1), a microtubule plus end directed kinesin, is required for the completion of cytokinesis. Previous studies have shown that MPP1 is upregulated in various types of bladder cancer. This article describes inhibitor screening leading to the identification of a new class of natural product inhibitors of MPP1. Two compounds with structural similarity, norlobaridone (1) and physodic acid (2), were found to inhibit MPP1. Physodic acid is not competitive with ATP, indicating the presence of an allosteric inhibitor-binding pocket. Initial drug-like property screening indicates that physodic acid is more soluble than norlobaridone and has more favorable lipophilicity. However, both suffer from high clearance in human microsomal stability assays mediated by the lability of the lactone ring as well as hydroxylation of the alkyl chains as shown by metabolite identification studies. In cell-based assays physodic acid is a weak inhibitor with EC50 values of about 30 μM in a range of tumor cell lines. The two depsidones identified and characterized here could be used for future improvement of their activity against MPP1 and will be useful chemical probes for studying this unique molecular motor in more depth. PMID:27300079

  1. Intermediate-scale, semicontinuous solid-phase fermentation process for production of fuel ethanol from sweet sorghum. [Saccharomyces cerevisiae

    SciTech Connect

    Gibbons, W.R.; Westby, C.A.; Dobbs, T.L.

    1986-01-01

    A novel, semicontinuous solid-phase fermentation system was used to produce fuel ethanol from sweet sorghum. The process was at an intermediate scale. In the process, dried and shredded sweet sorghum was rehydrated to 70% moisture, acidified to pH 2.0 to 3.0, and either pasteurized (12 h at 70 to 80/sup 0/C) or not pasteurized before spray inoculation with a broth culture of Saccharomyces cerevisiae. Fermented pulp exited the semicontinuous fermentor after a retention time of 72 h and contained approximately 6% (vol/vol) ethanol. Ethanol yields from dry sweet sorghum were 176 to 179 liters/10/sup 3/kg (85% of theoretical). Production costs for a greatly scaled-up (x1400) conceptual version of this system were projected by calculation to average $0.47/liter for 95% ethanol. The calculated energy balance (energy output/energy input ratio) was estimated to be 1.05 when pasteurization was included and 1.31 when pasteurization was omitted. In calculating the energy balances, the output energy of the protein feed byproduct and the input energy for growing the sweet sorghum were not considered. A design for the scaled-up plant (farm scale) is provided.

  2. Continuous, farm-scale, solid-phase fermentation process for fuel ethanol and protein feed production from fodder beets

    SciTech Connect

    Gibbons, W.R.; Westby, C.A.; Dobbs, T.L.

    1984-01-01

    Fuel ethanol (95%) was produced from fodder beets in two farm-scale processes. In the first process, involving conventional submerged fermentation of the fodder beets in a mash, ethanol and a feed (PF) rich in protein, fat, and fiber were produced. Ethanol yields of 70 L/metric ton (17 gal/ton) were obtained; however, resulting beers had low ethanol concentrations )3-5% (v/v)). The high viscosity of medium and low sugar, beet mashes caused mixing problems which prevented any further increase of beet sugar in the mash. This severely limited the maximum attainable ethanol concentration during fermentation, thereby making the beer costly to distill into fuel ethanol and the process energy inefficient. In order to achieve distillably worthwhile ethanol concentrations of 8-10% (v/v), a solid phase fermentation process (continuous) was developed and tested. In preliminary trials, this system produced fermented pulp with over 8% (v/v) ethanol corresponding to an ethanol yield of 87 L/metric ton (21 gal/ton). Production costs with this novel process are $0.47/L ($1.77/gal) and the energy balance is 2.11. These preliminary cost estimates indicate that fodder beets are potentially competitive with corn as an ethanol feedstock. Additional research, however, is warranted to more precisely refine individual costs, energy balances and the actual value of the PF.

  3. Sulfonated nanocellulose for the efficient dispersive micro solid-phase extraction and determination of silver nanoparticles in food products.

    PubMed

    Ruiz-Palomero, Celia; Soriano, M Laura; Valcárcel, Miguel

    2016-01-01

    This paper reports a simple approach to Analytical Nanoscience and Nanotechnology (AN&N) that integrates the nanotool, sulfonated nanocellulose (s-NC), and nanoanalyte, silver nanoparticles (AgNPs), in the same analytical process by using an efficient, environmentally friendly dispersive micro solid-phase extraction (D-μSPE) capillary electrophoresis (CE) method with s-NC as sorbent material. Introducing negatively charged sulfate groups onto the surface of cellulose enhances its surface chemistry and enables the extraction and preconcentration of AgNPs of variable diameter (10, 20 and 60nm) and shell composition (citrate and polyvinylpyrrolidone coatings) from complex matrices into a cationic surfactant. In this way, AgNPs of diverse nature were successfully extracted onto the s-NC sorbent and then desorbed into an aqueous solution containing thiotic acid (TA) prior to CE without the need for any labor-intensive cleanup. The ensuing eco-friendly D-μSPE method exhibited a linear response to AgNPs with a limit of detection (LOD) of 20μg/L. Its ability to specifically recognize AgNPs of different sizes was checked in orange juice and mussels, which afforded recoveries of 70.9-108.4%. The repeatability of the method at the limit of quantitation (LOQ) level was 5.6%. Based on the results, sulfonated nanocellulose provides an efficient, cost-effective analytical nanotool for the extraction of AgNPs from food products. PMID:26116191

  4. Separation of aromatic carboxylic acids using quaternary ammonium salts on reversed-phase HPLC. 2. Application for the analysis of Loy Yang coal oxidation products

    SciTech Connect

    Kawamura, K.; Okuwaki, A.; Verheyen, T.V.; Perry, G.J.

    2006-07-01

    In order to develop separation processes and analytical methods for aromatic carboxylic acids for the coal oxidation products, the separation behavior of aromatic carboxylic acids on a reversed-phase HPLC using eluent containing quaternary ammonium salt was optimized using the solvent gradient method. This method was applied for the analysis of Loy Yang coal oxidation products. It was confirmed that the analytical data using this method were consistent with those determined using gas chromatography.

  5. PRODUCTS OF THE GAS-PHASE REACTIONS OF THE OH RADICAL WITH N-BUTYL METHYL ETHER AND 2-ISOPROPOXYETHANOL: REACTIONS OF ROC(O)< RADICALS. (R825252)

    EPA Science Inventory

    The products of the gas-phase reactions of the OH radical with n-butyl methyl ether and 2-isopropoxyethanol in the presence of NO have been investigated at 298 ? 2 K and 740 Torr total pressure of air by gas chromatography and in situ atmospheric pressure ionization...

  6. Investigation of the formation of benzoyl peroxide, benzoic anhydride, and other potential aerosol products from gas-phase reactions of benzoylperoxy radicals

    NASA Astrophysics Data System (ADS)

    Strollo, Christen M.; Ziemann, Paul J.

    2016-04-01

    The secondary organic aerosol (SOA) products of the reaction of benzaldehyde with Cl atoms and with OH radicals in air in the absence of NOx were investigated in an environmental chamber in order to better understand the possible role of organic peroxy radical self-reactions in SOA formation. SOA products and authentic standards were analyzed using mass spectrometry and liquid chromatography, and results show that the yields of benzoyl peroxide (C6H5C(O)OO(O)CC6H5) and benzoic anhydride (C6H5C(O)O(O)CC6H5), two potential products from the gas-phase self-reaction of benzoylperoxy radicals (C6H5C(O)OO·), were less than 0.1%. This is in contrast to results of recent studies that have shown that the gas-phase self-reactions of β-nitrooxyperoxy radicals formed from reactions of isoprene with NO3 radicals form dialkyl peroxides that contribute significantly to gas-phase and SOA products. Such reactions have also been proposed to explain the gas-phase formation of extremely low volatility dimers from autooxidation of terpenes. The results obtained here indicate that, at least for benzoylperoxy radicals, the self-reactions form only benzoyloxy radicals. Analyses of SOA composition and volatility were inconclusive, but it appears that the SOA may consist primarily of oligomers formed through heterogeneous/multiphase reactions possibly involving some combination of phenol, benzaldehyde, benzoic acid, and peroxybenzoic acid.

  7. 30 CFR 203.43 - To which production do I apply the RSV earned from qualified deep wells or qualified phase 1...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false To which production do I apply the RSV earned from qualified deep wells or qualified phase 1 ultra-deep wells on my lease? 203.43 Section 203.43 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT RELIEF OR REDUCTION IN...

  8. The use of a housecleaning product in an indoor environment leading to oxygenated polar compounds and SOA formation: Gas and particulate phase chemical characterization

    NASA Astrophysics Data System (ADS)

    Rossignol, S.; Rio, C.; Ustache, A.; Fable, S.; Nicolle, J.; Même, A.; D'Anna, B.; Nicolas, M.; Leoz, E.; Chiappini, L.

    2013-08-01

    This work investigates Secondary Organic Aerosol (SOA) formed by limonene ozonolysis using a housecleaning product in indoor environment. This study combines simulation chamber ozonolysis experiments and field studies in an experimental house allowing different scenarios of housecleaning product use in real conditions. Chemical speciation has been performed using a new method based on simultaneous sampling of both gas and particulate phases on sorbent tubes and filters. This method allowed the identification and quantification of about 35 products in the gas and particulate phases. Among them, products known to be specific from limonene ozonolysis such as limononaldehyde, ketolimonene and ketolimonic acid have been detected. Some other compounds such as 2-methylbutanoic acid had never been detected in previous limonene ozonolysis studies. Some compounds like levulinic acid had already been detected but their formation remained unexplained. Potential reaction pathways are proposed in this study for these compounds. For each experiment, chemical data are coupled together with physical characterization of formed particles: mass and size and number distribution evolution which allowed the observation of new particles formation (about 87,000 particle cm-3). The chemical speciation associated to aerosol size distribution results confirmed that limonene emitted by the housecleaning product was responsible for SOA formation. To our knowledge, this work provides the most comprehensive analytical study of detected compounds in a single experiment for limonene ozonolysis in both gaseous and particulate phases in real indoor environment.

  9. Experience from design, prototyping and production of a DC-DC conversion powering scheme for the CMS Phase-1 Pixel Upgrade

    NASA Astrophysics Data System (ADS)

    Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Preuten, M.; Rauch, M.; Schmitz, S.; Wlochal, M.

    2016-02-01

    The CMS collaboration has adopted a DC-DC conversion powering scheme for the Phase-1 Upgrade of its pixel detector. DC-DC buck converters with a conversion ratio of around 3 are installed on the support structures, outside of the sensitive tracking region, requiring a re-design of the low and high voltage distribution to the pixel modules. After several years of R&D, the project has entered the production phase. A total of 1800 DC-DC converters are being produced, and rigorous quality assurance and control is being employed during the production process. The testing program is outlined, results from mass production are presented and issues that have been encountered are described. In addition, two system level challenges, namely the choice of output voltage in the presence of large, load-dependent voltage drops, and the thermal management required to remove the heat load caused by the DC-DC converters, are discussed.

  10. Integrated two-liquid phase bioconversion and product-recovery processes for the oxidation of alkanes: process design and economic evaluation

    PubMed

    Mathys; Schmid; Witholt

    1999-08-20

    Pseudomonas oleovorans and recombinant strains containing the alkane oxidation genes can produce alkane oxidation products in two-liquid phase bioreactor systems. In these bioprocesses the cells, which grow in the aqueous phase, oxidize apolar, non-water soluble substrates. The apolar products typically accumulate in the emulsified apolar phase. We have studied both the bioconversion systems and several downstream processing systems to separate and purify alkanols from these two-liquid phase media. Based on the information generated in these studies, we have now designed bioconversion and downstream processing systems for the production of 1-alkanols from n-alkanes on a 10 kiloton/yr scale, taking the conversion of n-octane to 1-octanol as a model system. Here, we describe overall designs of fed-batch and continuous-fermentation processes for the oxidation of octane to 1-octanol by Pseudomonas oleovorans, and we discuss the economics of these processes. In both systems the two-liquid phase system consists of an apolar phase with hexadecene as the apolar carrier solvent into which n-octane is dissolved, while the cells are present in the aqueous phase. In one system, multiple-batch fermentations are followed by continuous processing of the product from the separated apolar phase. The second system is based on alkane oxidation by continuously growing cultures, again followed by continuous processing of the product. Fewer fermentors were required and a higher space-time-yield was possible for production of 1-octanol in a continuous process. The overall performance of each of these two systems has been modeled with Aspen software. Investment and operating costs were estimated with input from equipment manufacturers and bulk-material suppliers. Based on this study, the production cost of 1-octanol is about 7 US$kg-1 when produced in the fed-batch process, and 8 US$kg-1 when produced continuously. The comparison of upstream and downstream capital costs and production

  11. Simple Heat Treatment for Production of Hot-Dip Galvanized Dual Phase Steel Using Si-Al Steels

    NASA Astrophysics Data System (ADS)

    Equihua-Guillén, F.; García-Lara, A. M.; Muñíz-Valdes, C. R.; Ortíz-Cuellar, J. C.; Camporredondo-Saucedo, J. E.

    2014-01-01

    This work presents relevant metallurgical considerations to produce galvanized dual phase steels from low cost aluminum-silicon steels which are produced by continuous strip processing. Two steels with different contents of Si and Al were austenized in the two-phase field ferrite + austenite (α + γ) in a fast manner to obtain dual phase steels, suitable for hot-dip galvanizing process, under typical parameters of continuous annealing processing line. Tensile dual phase properties were obtained from specimens cooled from temperature below Ar3, held during 3 min, intermediate cooling at temperature above Ar1 and quenching in Zn bath at 465 °C. The results have shown typical microstructure and tensile properties of galvanized dual phase steels. Finally, the synergistic effect of aluminum, silicon, and residual chromium on martensite start temperature ( M s), critical cooling rate ( C R), volume fraction of martensite, and tensile properties has been studied.

  12. An induction Linac approach to phase rotation of a muon bunch in the production region of {mu}{sup +}-{mu}{sup {minus}} colliders

    SciTech Connect

    Turner, W.C.

    1995-11-22

    The possibility of using an induction linac for phase rotation, or equivalently flattening the head to tail mean energy sweep, of a muon bunch in the production region of a {mu}{sup +} {minus} {mu}{sup {minus}} is examined. Axial spreading of an accelerating bunch is analyzed and the form of appropriate induction cell voltage waveforms is derived. A set of parametric equations for the induction accelerator structure is given and specific solutions are presented which demonstrate the technological feasibility of the induction linac approach to phase rotation.

  13. Extractive fermentation for improved production and recovery of lipase derived from Burkholderia cepacia using a thermoseparating polymer in aqueous two-phase systems.

    PubMed

    Show, Pau Loke; Tan, Chin Ping; Shamsul Anuar, Mohd; Ariff, Arbakariya; Yusof, Yus Aniza; Chen, Soo Kien; Ling, Tau Chuan

    2012-07-01

    An extractive fermentation technique was developed using a thermoseparating reagent to form a two-phase system for simultaneous cell cultivation and downstream processing of extracellular Burkholderia cepacia lipase. A 10% (w/w) solution of ethylene oxide-propylene oxide (EOPO) with a molecular mass of 3900 g/mol and pH 8.5, a 200 rpm speed, and 30 °C were selected as the optimal conditions for lipase production (55 U/ml). Repetitive batch fermentation was performed by continuous replacement of the top phase every 24h, which resulted in an average cell growth mass of 4.7 g/L for 10 extractive batches over 240 h. In scaling-up the process, a bench-scale bioreactor was tested under the conditions that had been optimized in flasks. The production rate and recovery yield were higher in the bioreactor compared to fermentation performed in flasks. PMID:22061444

  14. Direct stereochemical resolution of aspartame stereoisomers and their degradation products by high-performance liquid chromatography on a chiral crown ether based stationary phase.

    PubMed

    Motellier, S; Wainer, I W

    1990-09-21

    The direct stereochemical resolution of the four stereoisomers of aspartame (N-DL-alpha-aspartyl-DL-phenylalanine methyl ester) and their degradation products was achieved on a high-performance liquid chromatography chiral stationary phase based upon a chiral crown ether. The chromatographic conditions included a mobile phase composed of aqueous perchloric acid adjusted to a pH of 2.8 and modified with 1.5% of 2-propanol and a temperature gradient. The active L,L-isomer (sold under the brand name NutraSweet) was measured in a diet cola and coffee sweetened with NutraSweet. Degradation products of NutraSweet were also detected but no racemization of stereochemical contamination was observed. PMID:2150410

  15. Determination of benzalkonium chloride in eye care products by high-performance liquid chromatography and solid-phase extraction or on-line column switching.

    PubMed

    Elrod, L; Golich, T G; Morley, J A

    1992-11-20

    Benzalkonium chloride (BAK) is a mixture of alkylbenzyldimethylammonium chlorides, which is commonly used as a bacteriostat. In this work, the three major homologues of BAK are quantitated in the over-the-counter eye care products Murine and Murine Plus using high-performance liquid chromatography (HPLC). The analytes are separated from various product excipients and concentrated by either solid-phase extraction onto Sep-Pak C18 cartridges or by an on-line column-switching technique using 1-cm reversed-phase precolumns. Absolute recoveries of BAK homologues by the solid-phase extraction technique ranged from 97.2 to 98.7% for standards and from 98.0 to 98.4% for samples. Absolute recovery of the BAK homologues by the column-switching technique was 101.3% for standards and ranged from 99.9 to 103.7% for samples. Relative recoveries were quantitative by both techniques. Assay precision (R.S.D. values) were +/- 2.2% to +/- 2.6% and +/- 0.4% to +/- 0.8% by solid-phase extraction and column-switching techniques, respectively. The method provides advantages of high sample throughput, excellent column life and automation. PMID:1474126

  16. Quantitative determination of usnic acid in Usnea lichen and its products by reversed-phase liquid chromatography with photodiode array detector.

    PubMed

    Ji, Xiuhong; Khan, Ikhlas A

    2005-01-01

    Usnic acid, a lichen substance, has a wide range of pharmaceutical applications, including antibiotic, antimycotic, antifeedant, antitubercular, antitumor, and analgesic activities. Some products containing usnic acid are marketed as weight control supplements; however, hepatotoxicity and acute liver failures were reported as severe side effects. The usnic acid content present in the plant materials and market products was analyzed by reversed-phase high-pressure liquid chromatography with a photodiode array detector at 233 nm. A Waters XTerra RP18 (150 x 4.6 mm; 5 microm particle size) column was the stationary phase; mobile phase was aqueous 0.1% acetic acid and acetonitrile gradient at flow rate of 1.0 mL/min. The temperature was held constant at 30 degrees C. The retention time of usnic acid was approximately 13.3 min. Acetone extraction of the samples took place with sonication. The precision of the method was confirmed by a standard deviation below 3.0% (n=3) and usnic acid recovery was 99.0%. Limit of detection was 0.4 microg/mL and the response was linear from 1.4 to 570.0 microg/mL with a correlation coefficient (R2) of 0.9991. The content of usnic acid in 4 raw materials and 22 finished products was analyzed. PMID:16385974

  17. [Contribution of different processes in wetland soil N2O production in different restoration phases of the Yellow River estuary, China].

    PubMed

    Sun, Wen-Guang; Sun, Zhi-Gao; Gan, Zhuo-Ting; Sun, Wan-Long; Wang, Wei

    2014-08-01

    By using the method of time-space mutual substitution, the contribution of different processes in wetland soil N2O production was studied in the un-restoration wetland (R0), restoration wetland since 2007 (R2007) and restoration wetland since 2002 (R2002) of the Yellow River estuary to evaluate the effectiveness of the restoration projects. Results showed wetland soil total N2O production had a significant difference in different restoration phases, but the N2O release was the main source. The N2O production in restoration wetland was higher than that in un-restoration wetland. The N2O production wss mainly due to the nitrification and nitrifier denitrification processes, while the denitrification process had great weakening effects on N2O production, which was closely related to the physical and chemical properties of wetland soils in different restoration phases. The non-biological processes made greater contributions to N2O production and these were mainly due to that iron was reductive, while the Yellow River estuary was an area of highly active iron. Although N2O production in wetland soils was the results of biological processes combined with non-biological processes in different restoration phases, non-biological processes had larger influences and should be paid a special attention. There were different influences on wetland soil processes generating N2O between temperature and water content, indicating responses of soil microbial activities to temperature and water content were different. In addition, the N2O production contents ranged from 0.37 +/- 0.08 nmol x (kg x h) (-1) to 9.75 +/- 7.64 nmol x (kg x h) (-1) in marshes of the Yellow River estuary, which was slightly higher than those in the S. alterniflora wetland soils of the Min River estuary, but significantly lower than those in the C. malaccensis wetland soils of the Min River estuary, the grassland soils and the aerobic forest soils. We found that the long-term implements of ecological

  18. Multi-phase glass-ceramics as a waste form for combined fission products: alkalis, alkaline earths, lanthanides, and transition metals

    SciTech Connect

    Crum, Jarrod V.; Turo, Laura A.; Riley, Brian J.; Tang, Ming; Kossoy, Anna

    2012-04-01

    In this study, multi-phase silicate-based glass-ceramics were investigated as an alternate waste form for immobilizing non-fissionable products from used nuclear fuel. Currently, borosilicate glass is the waste form selected for immobilization of this waste stream, however, the low thermal stability and solubility of MoO{sub 3} in borosilicate glass translates into a maximum waste loading in the range of 15-20 mass%. Glass-ceramics provide the opportunity to target durable crystalline phases, e.g., powellite, oxyapatite, celsian, and pollucite, that will incorporate MoO{sub 3} as well as other waste components such as lanthanides, alkalis, and alkaline earths at levels 2X the solubility limits of a single-phase glass. In addition a glass-ceramic could provide higher thermal stability, depending upon the properties of the crystalline and amorphous phases. Glass-ceramics were successfully synthesized at waste loadings of 42, 45, and 50 mass% with the following glass additives: B{sub 2}O{sub 3}, Al{sub 2}O{sub 3}, CaO and SiO{sub 2} by slow cooling form from a glass melt. Glass-ceramics were characterized in terms of phase assemblage, morphology, and thermal stability. The targeted phases: powellite and oxyapatite were observed in all of the compositions along with a lanthanide borosilicate, and cerianite. Results of this initial investigation of glass-ceramics show promise as a potential waste form to replace single-phase borosilicate glass.

  19. INCORPORATION OF PENTAVALENT NEPTUNIUM INTO URANYL PHASES THAT MAY FORM AS ALTERATION PRODUCTS OF SPENT NUCLEAR FUEL

    SciTech Connect

    NA

    2005-06-21

    Laboratory-scale simulations and studies of natural analogues have shown that alteration of spent nuclear fuel in a moist, oxidizing environment results in the formation of a variety of uranyl phases. Neptunium-237 has a half-life of 2.14 million years, and the pentavalent oxidation state is soluble in groundwater. Release of Np-237 from spent nuclear fuel in a geological repository may significantly impact the long-term performance of such a repository. Incorporation of Np, in the pentavalent oxidation state, into uranyl phases by substitution for hexavalent U is likely because of the similarity of the coordination environments of these two cations, but a charge-balance mechanism is required for substitution. A preliminary study has shown incorporation of pentavalent Np into powders of the uranyl silicate uranophane, and Na-compreignacite, a uranyl oxyhydrate [1]. Using synthesis experiments under mild hydrothermal conditions, we are examining the incorporation of pentavalent Np into selected uranyl oxyhydrates and silicates as a function of temperature and the pH of the mother solution. Analyses of powders of these uranyl phases has demonstrated both temperature and pH dependences for incorporation. Experiments are underway directed at the synthesis of single crystals of uranyl phases in the presence of 500-750 ppm pentavalent Np. The intent is to develop a basic understanding of the crystallographic and crystal chemical factors that impact incorporation of pentavalent Np into uranyl phases. Following synthesis, crystals are analyzed for Np using laser ablation ICP-MS. Preliminary results for Na-substituted metaschoepite indicate significant Np has been incorporated into the crystals. Additional phases under study include compreignacite, becquerelite, soddyite, zippeite, and (UO{sub 2}){sub 3}(PO{sub 4}){sub 2}(H{sub 2}O){sub 4}.

  20. Are You Ready Phase Two? Pricing Changes and Commercial Products Added to DOE High-Performance Windows Program

    SciTech Connect

    Mapes, Terry S.

    2011-05-01

    This article, for publication in Door and Window Manufacturer magazine, describes DOE's High Performance Windows Volume Purchase Program, WVPP, and how PNNL, which manages the program for DOE, is assisting DOE in the transition to the next phase (Phase II), which begins in May. While the foundation of the program will remain relatively unchanged, PNNL is employing several new strategies to continue the momentum built during the program's first full year of implementation. The program helps buyers and manufacturers to develop a market for highly insulating windows and low-E storm windows at affordable prices and thereby overcome the principal barrier of cost.

  1. TVA/DOE integrated onfarm alcohol production system. Phase II. Progress report, October 1981-February 1982. Circular Z-134

    SciTech Connect

    Badger, P.C.; Pile, R.S.; Burch, D.W.; Mays, D.A.; Lewis, J.M.

    1982-03-01

    Equipment and procedures necessary for using a grain (corn) feedstock for onfarm alcohol production were refined and documented to provide benchmark data. Also, significant progress was made in developing technology to convert other agricultural crops into 190-proof alcohol with the farm-sized alcohol production facility. This was achieved by modifying the base alcohol-from-grain facility to process the nongrain feedstocks (Irish potatoes, sweet sorghum, sweet potatoes, sugar beets, fodder beets, and Jerusalem artichokes) being evaluated in field production trials by TVA. Alcohol production capacities of cull potatoes, water chestnuts, and cull apples were also tested. A computerized investment model was refined to predict rapidly the economic implications for alcohol production levels, feedstocks, and various system components.

  2. Detection of aqueous phase chemical warfare agent degradation products by negative mode ion mobility time-of-flight mass spectrometry [IM(tof)MS].

    PubMed

    Steiner, Wes E; Harden, Charles S; Hong, Feng; Klopsch, Steve J; Hill, Herbert H; McHugh, Vincent M

    2006-02-01

    The use of negative ion monitoring mode with an atmospheric pressure ion mobility orthogonal reflector time-of-flight mass spectrometer [IM(tof)MS] to detect chemical warfare agent (CWA) degradation products from aqueous phase samples has been determined. Aqueous phase sampling used a traditional electrospray ionization (ESI) source for sample introduction and ionization. Certified reference materials (CRM) of CWA degradation products for the detection of Schedule 1, 2, or 3 toxic chemicals or their precursors as defined by the chemical warfare convention (CWC) treaty verification were used in this study. A mixture of six G-series nerve related CWA degradation products (EMPA, IMPA, EHEP, IHEP, CHMPA, and PMPA) and their related collision induced dissociation (CID) fragment ions (MPA and EPA) were found in each case to be clearly resolved and detected using the IM(tof)MS instrument in negative ion monitoring mode. Corresponding ions, masses, drift times, K(o) values, and signal intensities for each of the CWA degradation products are reported. PMID:16413205

  3. Effect of high-temperature stress on microalgae at the end of the logarithmic phase for the efficient production of lipid.

    PubMed

    Han, Fei; Pei, Haiyan; Hu, Wenrong; Han, Lin; Zhang, Shuo; Ma, Guixia

    2016-10-01

    Efficient production of microalgae lipid is significant for the production of renewable biodiesel. In the present study, the high temperature of 40°C as stress environment was tested for stimulating lipid accumulation after the microalgae (Scenedesmus quadricauda) cells in suitable conditions grew to the end of the logarithmic phase. Different stress cultivation times of 1, 2, 3, 4, 5 and 6 days were studied. Interestingly, the lipid content and productivity reached 33.5% and 23.2 mg/L d after one day stress cultivation, showing substantial improvements of 39.6% and 33.3% compared with that in the untreated (day 0) microalgae cells, respectively. Longer stress time led to the decrease of biomass and lipid content compared with the untreated microalgae. However, a maximum protein content of 58.7% was obtained after six days. The stress cultivation at the end of the microalgae exponential phase for one day at a high temperature of 40°C could be a very useful industrial approach for efficiently promoting lipid content and biodiesel production. PMID:26930246

  4. Phase partitioning and volatility of secondary organic aerosol components formed from α-pinene ozonolysis and OH oxidation: the importance of accretion products and other low volatility compounds

    NASA Astrophysics Data System (ADS)

    Lopez-Hilfiker, F. D.; Mohr, C.; Ehn, M.; Rubach, F.; Kleist, E.; Wildt, J.; Mentel, Th. F.; Carrasquillo, A.; Daumit, K.; Hunter, J.; Kroll, J. H.; Worsnop, D.; Thornton, J. A.

    2015-02-01

    We measured a large suite of gas and particle phase multi-functional organic compounds with a Filter Inlet for Gases and AEROsols (FIGAERO) coupled to a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) developed at the University of Washington. The instrument was deployed on environmental simulation chambers to study monoterpene oxidation as a secondary organic aerosol (SOA) source. We focus here on results from experiments utilizing an ionization method most selective towards acids (acetate negative ion proton transfer), but our conclusions are based on more general physical and chemical properties of the SOA. Hundreds of compounds were observed in both gas and particle phases, the latter being detected upon temperature programmed thermal desorption of collected particles. Particulate organic compounds detected by the FIGAERO HR-ToF-CIMS are highly correlated with, and explain at least 25-50% of, the organic aerosol mass measured by an Aerodyne Aerosol Mass Spectrometer (AMS). Reproducible multi-modal structures in the thermograms for individual compounds of a given elemental composition reveal a significant SOA mass contribution from large molecular weight organics and/or oligomers (i.e. multi-phase accretion reaction products). Approximately 50% of the HR-ToF-CIMS particle phase mass is associated with compounds having effective vapor pressures 4 or more orders of magnitude lower than commonly measured monoterpene oxidation products. The relative importance of these accretion-type and other extremely low volatility products appears to vary with photochemical conditions. We present a desorption temperature based framework for apportionment of thermogram signals into volatility bins. The volatility-based apportionment greatly improves agreement between measured and modeled gas-particle partitioning for select major and minor components of the SOA, consistent with thermal decomposition during desorption causing the conversion of

  5. Phase partitioning and volatility of secondary organic aerosol components formed from α-pinene ozonolysis and OH oxidation: the importance of accretion products and other low volatility compounds

    NASA Astrophysics Data System (ADS)

    Lopez-Hilfiker, F. D.; Mohr, C.; Ehn, M.; Rubach, F.; Kleist, E.; Wildt, J.; Mentel, Th. F.; Carrasquillo, A. J.; Daumit, K. E.; Hunter, J. F.; Kroll, J. H.; Worsnop, D. R.; Thornton, J. A.

    2015-07-01

    We measured a large suite of gas- and particle-phase multi-functional organic compounds with a Filter Inlet for Gases and AEROsols (FIGAERO) coupled to a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) developed at the University of Washington. The instrument was deployed on environmental simulation chambers to study monoterpene oxidation as a secondary organic aerosol (SOA) source. We focus here on results from experiments utilizing an ionization method most selective towards acids (acetate negative ion proton transfer), but our conclusions are based on more general physical and chemical properties of the SOA. Hundreds of compounds were observed in both gas and particle phases, the latter being detected by temperature-programmed thermal desorption of collected particles. Particulate organic compounds detected by the FIGAERO-HR-ToF-CIMS are highly correlated with, and explain at least 25-50 % of, the organic aerosol mass measured by an Aerodyne aerosol mass spectrometer (AMS). Reproducible multi-modal structures in the thermograms for individual compounds of a given elemental composition reveal a significant SOA mass contribution from high molecular weight organics and/or oligomers (i.e., multi-phase accretion reaction products). Approximately 50 % of the HR-ToF-CIMS particle-phase mass is associated with compounds having effective vapor pressures 4 or more orders of magnitude lower than commonly measured monoterpene oxidation products. The relative importance of these accretion-type and other extremely low volatility products appears to vary with photochemical conditions. We present a desorption-temperature-based framework for apportionment of thermogram signals into volatility bins. The volatility-based apportionment greatly improves agreement between measured and modeled gas-particle partitioning for select major and minor components of the SOA, consistent with thermal decomposition during desorption causing the conversion of

  6. Phase partitioning and volatility of secondary organic aerosol components formed from α-pinene ozonolysis and OH oxidation: the importance of accretion products and other low volatility compounds

    DOE PAGESBeta

    Lopez-Hilfiker, F. D.; Mohr, C.; Ehn, M.; Rubach, F.; Kleist, E.; Wildt, J.; Mentel, Th. F.; Carrasquillo, A. J.; Daumit, K. E.; Hunter, J. F.; et al

    2015-07-16

    We measured a large suite of gas- and particle-phase multi-functional organic compounds with a Filter Inlet for Gases and AEROsols (FIGAERO) coupled to a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) developed at the University of Washington. The instrument was deployed on environmental simulation chambers to study monoterpene oxidation as a secondary organic aerosol (SOA) source. We focus here on results from experiments utilizing an ionization method most selective towards acids (acetate negative ion proton transfer), but our conclusions are based on more general physical and chemical properties of the SOA. Hundreds of compounds were observed in both gas andmore » particle phases, the latter being detected by temperature-programmed thermal desorption of collected particles. Particulate organic compounds detected by the FIGAERO–HR-ToF-CIMS are highly correlated with, and explain at least 25–50 % of, the organic aerosol mass measured by an Aerodyne aerosol mass spectrometer (AMS). Reproducible multi-modal structures in the thermograms for individual compounds of a given elemental composition reveal a significant SOA mass contribution from high molecular weight organics and/or oligomers (i.e., multi-phase accretion reaction products). Approximately 50 % of the HR-ToF-CIMS particle-phase mass is associated with compounds having effective vapor pressures 4 or more orders of magnitude lower than commonly measured monoterpene oxidation products. The relative importance of these accretion-type and other extremely low volatility products appears to vary with photochemical conditions. We present a desorption-temperature-based framework for apportionment of thermogram signals into volatility bins. The volatility-based apportionment greatly improves agreement between measured and modeled gas-particle partitioning for select major and minor components of the SOA, consistent with thermal decomposition during desorption causing the

  7. Phase partitioning and volatility of secondary organic aerosol components formed from α-pinene ozonolysis and OH oxidation: the importance of accretion products and other low volatility compounds

    DOE PAGESBeta

    Lopez-Hilfiker, F. D.; Mohr, C.; Ehn, M.; Rubach, F.; Kleist, E.; Wildt, J.; Mentel, Th. F.; Carrasquillo, A.; Daumit, K.; Hunter, J.; et al

    2015-02-18

    We measured a large suite of gas and particle phase multi-functional organic compounds with a Filter Inlet for Gases and AEROsols (FIGAERO) coupled to a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) developed at the University of Washington. The instrument was deployed on environmental simulation chambers to study monoterpene oxidation as a secondary organic aerosol (SOA) source. We focus here on results from experiments utilizing an ionization method most selective towards acids (acetate negative ion proton transfer), but our conclusions are based on more general physical and chemical properties of the SOA. Hundreds of compounds were observed in both gasmore » and particle phases, the latter being detected upon temperature programmed thermal desorption of collected particles. Particulate organic compounds detected by the FIGAERO HR-ToF-CIMS are highly correlated with, and explain at least 25–50% of, the organic aerosol mass measured by an Aerodyne Aerosol Mass Spectrometer (AMS). Reproducible multi-modal structures in the thermograms for individual compounds of a given elemental composition reveal a significant SOA mass contribution from large molecular weight organics and/or oligomers (i.e. multi-phase accretion reaction products). Approximately 50% of the HR-ToF-CIMS particle phase mass is associated with compounds having effective vapor pressures 4 or more orders of magnitude lower than commonly measured monoterpene oxidation products. The relative importance of these accretion-type and other extremely low volatility products appears to vary with photochemical conditions. We present a desorption temperature based framework for apportionment of thermogram signals into volatility bins. The volatility-based apportionment greatly improves agreement between measured and modeled gas–particle partitioning for select major and minor components of the SOA, consistent with thermal decomposition during desorption causing the

  8. Preparation and application of reversed phase chromatorotor for the isolation of natural products by centrifugal preparative chromatography

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method of preparation of Chromatorotor or plates with a reversed phase (RP) solid silica gel sorbent layer has been developed for preparative centrifugal chromatography. The RP-rotor plates consist of binder free RP solid SiO2 sorbent layers of different thicknesses paked between two supported cir...

  9. "Brief Report: Increase in Production of Spoken Words in Some Children with Autism after PECS Teaching to Phase III"

    ERIC Educational Resources Information Center

    Carr, Deborah; Felce, Janet

    2007-01-01

    The context for this work was an evaluation study [Carr, D., & Felce, J. A. (in press)] of the early phases of the Picture Exchange Communication System (PECS) [Frost, L. A., & Bondy, A. S. (1994). "The picture exchange communication system training manual." Cherry Hill, NJ: Pyramid Educational Consultants, Inc.; Frost, L. A., & Bondy, A. S.…

  10. Rocket motor exhaust products generated by the space shuttle vehicle during its launch phase (1976 design data)

    NASA Technical Reports Server (NTRS)

    Bowyer, J. M.

    1977-01-01

    The principal chemical species emitted and/or entrained by the rocket motors of the space shuttle vehicle during the launch phase of its trajectory are considered. Results are presented for two extreme trajectories, both of which were calculated in 1976.

  11. A high energy phase retarder for the simultaneous production of right- and left-handed circularly polarized x-rays

    SciTech Connect

    Venkataraman, C.T.; Lang, J.C.; Nelson, C.S.; Srajer, G.; Haeffner, D.R.; Shastri, S.D.

    1997-09-01

    The authors have fabricated and characterized the performance of a monolithic Ge Bragg-Laue phase retarder capable of simultaneously producing both right- and left-handed circularly polarized x rays. The energy range of operation of the phase retarder is between 50 and 100 keV making it well suited to the measurement of spin-dependent Compton profiles within the impulse approximation, primarily because of the increased momentum resolution and larger Compton scattering cross section available at these higher incident energies. Although the phase retarder was optimized for operation at 86 keV, it can produce highly circularly polarized x rays over a substantial energy range. The performance of the phase retarder was tested via magnetic Compton scattering measurements on an Fe sample at the undulator A of the Advanced Photon Source. It was found to perform well in terms of flux and degree of circular polarization thereby greatly reducing the data collection times required for this inherently weak scattering process.

  12. A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1. Volume 2, Geology and engineering

    SciTech Connect

    Overbey, W.K. Jr.; Reeves, T.K.; Salamy, S.P.; Locke, C.D.; Johnson, H.R.; Brunk, R.; Hawkins, L.

    1991-05-01

    This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The project has been conducted by Beckley College, Inc., and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center (METC). This section, Volume II, contains a detailed discussion of the methodology used and the geological and production information collected and analyzed for this study. A companion document, Volume 1, provides an overview of the program, technique and results of the study. In combination, Volumes I and II cover the completion of the research undertaken under Phase I of this DOE project, which included the identification of five high-potential sites for natural gas production on the Eccles Quadrangle, Raleigh County, West Virginia. Each of these sites was selected for its excellent potential for gas production from both relatively shallow coalbeds and the deeper, conventional reservoir formations.

  13. Product study of the gas-phase reactions of monoterpenes with the OH radical in the presence of NO(x)

    NASA Astrophysics Data System (ADS)

    Arey, Janet; Atkinson, Roger; Aschmann, Sara M.

    1990-10-01

    Hydroxyl radical reactions play an important role in the removal of monoterpenes from the troposphere during daytime hours, but there are few data available to date concerning the products of these reactions. From the gas-phase reactions of B-pinene and d-limonene with the OH radical in the presence of NO(x), the predicted products, 6,6-dimethylbicyclo(3.1.1)-heptan-2-one and 4-acetyl-1-methylcyclohexene, respectively, were observed with formation yields of 30.0 + or - 4.5 percent and 17.4 + or - 2.8 percent. On the basis of mass spectral data a number of ketone and keto-aldehyde products were tentatively identified in irradiated CH3ONO-NO-air-monoterpene mixtures of d-limonene, alpha-pinene, Delta(3)-carene, sabinene, and terpinolene.

  14. Solid phase bio-electrofermentation of food waste to harvest value-added products associated with waste remediation.

    PubMed

    Chandrasekhar, K; Amulya, K; Mohan, S Venkata

    2015-11-01

    A novel solid state bio-electrofermentation system (SBES), which can function on the self-driven bioelectrogenic activity was designed and fabricated in the laboratory. SBES was operated with food waste as substrate and evaluated for simultaneous production of electrofuels viz., bioelectricity, biohydrogen (H2) and bioethanol. The system illustrated maximum open circuit voltage and power density of 443 mV and 162.4 mW/m(2), respectively on 9 th day of operation while higher H2 production rate (21.9 ml/h) was observed on 19th day of operation. SBES system also documented 4.85% w/v bioethanol production on 20th day of operation. The analysis of end products confirmed that H2 production could be generally attributed to a mixed acetate/butyrate-type of fermentation. Nevertheless, the presence of additional metabolites in SBES, including formate, lactate, propionate and ethanol, also suggested that other metabolic pathways were active during the process, lowering the conversion of substrate into H2. SBES also documented 72% substrate (COD) removal efficiency along with value added product generation. Continuous evolution of volatile fatty acids as intermediary metabolites resulted in pH drop and depicted its negative influence on SBES performance. Bio-electrocatalytic analysis was carried out to evaluate the redox catalytic capabilities of the biocatalyst. Experimental data illustrated that solid-state fermentation can be effectively integrated in SBES for the production of value added products with the possibility of simultaneous solid waste remediation. PMID:26117418

  15. Kinetic and products study of the gas-phase reaction of Lewisite with ozone under atmospheric conditions.

    PubMed

    Wang, Haitao; Zhang, Yuanpeng; Guo, Xiaodi; Shao, Yusheng; Gao, Runli; Liang, Dejian; Sun, Hao

    2016-02-01

    The rate constant for the gas-phase reaction of O3 and Lewisite was studied in air using the smog chamber technique. The experiments were carried out under pseudo-first-order reaction conditions with [O3]≪[Lewisite]. The observed rate constant of O3 with Lewisite was (7.83 ± 0.38) × 10(-19)cm(3)/(molecule·sec) at 298 ± 2K. Lewisite was discussed in terms of reactivity with O3 and its relationship with the ionization potential. Our results show that the rate constant for the gas-phase reaction of O3 with Lewisite is in line with the trend of the rate constants of O3 with haloalkenes. PMID:26969539

  16. Feed Materials Production Center. Final phase-in report volume 12 of 15, productivity retention program, October 25, 1985--December 31, 1985

    SciTech Connect

    Elikan, L.

    1986-01-17

    This transition task focused on a review of the Productivity & Radiological Improvements Line Item Program (Package 1) and the Productivity Retention Programs (Packages 2, 3 & 4). Specific objectives include: (1) Understanding the status of the programs. (2) Identifying critical path projects. (3) Identifying current and potential problems. (4) Reviewing the process and procedures employed by NLO for Line Item projects, covering the planning, estimating, justifying, approving, and acquisition and construction of facilities. (5) Preparing recommendations. Primary effort in this study was focused on Packages 1 and 2, since this is where current NLO activity is concentrated. This allowed the authors to proceed with a minimum of interruptions to on-going work effort. This report will cover findings and recommendations for all four subtasks which were defined to address the completion of the four packages.

  17. Anthropogenic Sulfur Perturbations on Biogenic Oxidation: SO2 Additions Impact Gas-Phase OH Oxidation Products of α- and β-Pinene.

    PubMed

    Friedman, Beth; Brophy, Patrick; Brune, William H; Farmer, Delphine K

    2016-02-01

    In order to probe how anthropogenic pollutants can impact the atmospheric oxidation of biogenic emissions, we investigated how sulfur dioxide (SO2) perturbations impact the oxidation of two monoterpenes, α-and β-pinene. We used chemical ionization mass spectrometry to examine changes in both individual molecules and gas-phase bulk properties of oxidation products as a function of SO2 addition. SO2 perturbations impacted the oxidation systems of α-and β-pinene, leading to an ensemble of products with a lesser degree of oxygenation than unperturbed systems. These changes may be due to shifts in the OH:HO2 ratio from SO2 oxidation and/or to SO3 reacting directly with organic molecules. Van Krevelen diagrams suggest a shift from gas-phase functionalization by alcohol/peroxide groups to functionalization by carboxylic acid or carbonyl groups, consistent with a decreased OH:HO2 ratio. Increasing relative humidity dampens the impact of the perturbation. This decrease in oxygenation may impact secondary organic aerosol formation in regions dominated by biogenic emissions with nearby SO2 sources. We observed sulfur-containing organic compounds following SO2 perturbations of monoterpene oxidation; whether these are the result of photochemistry or an instrumental artifact from ion-molecule clustering remains uncertain. However, our results demonstrate that the two monoterpene isomers produce unique suites of oxidation products. PMID:26735899

  18. Design of a surface-based factory for the production of life support and technology support products. Phase 2: Integrated water system for a space colony

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Phase 2 of a conceptual design of an integrated water treatment system to support a space colony is presented. This includes a breathable air manufacturing system, a means of drilling for underground water, and storage of water for future use. The system is to supply quality water for biological consumption, farming, residential and industrial use and the water source is assumed to be artesian or subsurface and on Mars. Design criteria and major assumptions are itemized. A general block diagram of the expected treatment system is provided. The design capacity of the system is discussed, including a summary of potential users and the level of treatment required; and, finally, various treatment technologies are described.

  19. Offline solid-phase extraction for preconcentration of pharmaceuticals and personal care products in environmental water and their simultaneous determination using the reversed phase high-performance liquid chromatography method.

    PubMed

    G Archana; Dhodapkar, Rita; Kumar, Anupama

    2016-09-01

    The present study reports a precise and simple offline solid-phase extraction (SPE) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous determination of five representative and commonly present pharmaceuticals and personal care products (PPCPs), a new class of emerging pollutants in the aquatic environment. The target list of analytes including ciprofloxacin, acetaminophen, caffeine benzophenone and irgasan were separated by a simple HPLC method. The column used was a reversed-phase C18 column, and the mobile phase was 1 % acetic acid and methanol (20:80 v/v) under isocratic conditions, at a flow rate of 1 mL min(-1). The analytes were separated and detected within 15 min using the photodiode array detector (PDA). The linearity of the calibration curves were obtained with correlation coefficients 0.98-0.99.The limit of detection (LOD), limit of quantification (LOQ), precision, accuracy and ruggedness demonstrated the reproducibility, specificity and sensitivity of the developed method. Prior to the analysis, the SPE was performed using a C18 cartridge to preconcentrate the targeted analytes from the environmental water samples. The developed method was applied to evaluate and fingerprint PPCPs in sewage collected from a residential engineering college campus, polluted water bodies such as Nag river and Pili river and the influent and effluent samples from a sewage treatment plant (STP) situated at Nagpur city, in the peak summer season. This method is useful for estimation of pollutants present in microquantities in the surface water bodies and treated sewage as compared to nanolevel pollutants detected by mass spectrometry (MS) detectors. PMID:27502523

  20. Evaluation of Selected Chemical Processes for Production of Low-cost Silicon, Phase 3. [using a fluidized bed reactor

    NASA Technical Reports Server (NTRS)

    Blocher, J. M., Jr.; Browning, M. F.

    1979-01-01

    The construction and operation of an experimental process system development unit (EPSDU) for the production of granular semiconductor grade silicon by the zinc vapor reduction of silicon tetrachloride in a fluidized bed of seed particles is presented. The construction of the process development unit (PDU) is reported. The PDU consists of four critical units of the EPSDU: the fluidized bed reactor, the reactor by product condenser, the zinc vaporizer, and the electrolytic cell. An experimental wetted wall condenser and its operation are described. Procedures are established for safe handling of SiCl4 leaks and spills from the EPSDU and PDU.

  1. Purine biosynthesis, riboflavin production, and trophic-phase span are controlled by a Myb-related transcription factor in the fungus Ashbya gossypii.

    PubMed

    Mateos, Laura; Jiménez, Alberto; Revuelta, José L; Santos, María A

    2006-07-01

    Ashbya gossypii is a natural riboflavin overproducer used in the industrial production of the vitamin. We have isolated an insertional mutant exhibiting higher levels of riboflavin production than the wild type. DNA analysis of the targeted locus in the mutant strain revealed that a syntenic homolog of the Saccharomyces cerevisiae BAS1 gene, a member of the Myb family of transcription factors, was inactivated. Directed gene disruption of AgBAS1 confirmed the phenotype observed for the insertional mutant, and the Deltabas1 mutant also showed auxotrophy for adenine and several growth defects, such as a delay in the germination of the spores and an abnormally prolonged trophic phase. Additionally, we demonstrate that the DNA-binding domain of AgBas1p is able to bind to the Bas1-binding motifs in the AgADE4 promoter; we also show a clear nuclear localization of a green fluorescent protein-Bas1 fusion protein. Real-time quantitative PCR analyses comparing the wild type and the Deltabas1 mutant revealed that AgBAS1 was responsible for the adenine-mediated regulation of the purine and glycine pathways, since the transcription of the ADE4 and SHM2 genes was virtually abolished in the Deltabas1 mutant. Furthermore, the transcription of ADE4 and SHM2 in the Deltabas1 mutant did not diminish during the transition from the trophic to the productive phase did not diminish, in contrast to what occurred in the wild-type strain. A C-terminal deletion in the AgBAS1 gene, comprising a hypothetical regulatory domain, caused constitutive activation of the purine and glycine pathways, enhanced riboflavin overproduction, and prolonged the trophic phase. Taking these results together, we propose that in A. gossypii, AgBAS1 is an important transcription factor that is involved in the regulation of different physiological processes, such as purine and glycine biosynthesis, riboflavin overproduction, and growth. PMID:16820505

  2. Determination of isothiazolinone preservatives in cosmetics and household products by matrix solid-phase dispersion followed by high-performance liquid chromatography-tandem mass spectrometry.

    PubMed

    Alvarez-Rivera, Gerardo; Dagnac, Thierry; Lores, Marta; Garcia-Jares, Carmen; Sanchez-Prado, Lucia; Lamas, J Pablo; Llompart, Maria

    2012-12-28

    In this work, the development of a new efficient methodology applying, for the first time, matrix solid phase dispersion (MSPD) for the determination of sensitizer isothiazolinone biocides in cosmetics and household products - 2-methyl-3-isothiazolinone (MI), 5-chloro-2-methyl-3-isothiazolinone (CMI), 1,2-benzisothiazolinone (BzI) and 2-octyl-3-isothiazolinone (OI) - is described. The main factors affecting the MSPD extraction procedure, the dispersive phase and the elution solvent, are assessed and optimized through a multicategorical experimental design, using a real cosmetic sample. The most suitable extraction conditions comprise the use of 2g of florisil as dispersive phase and 5 mL of methanol as elution solvent. Subsequently, the extract is readily analyzed by HPLC-MS/MS without any further clean-up or concentration steps. Method performance was evaluated demonstrating to have a broad linear range (R(2)>0.9980) and limits of detection (LOD) and quantification (LOQ) at the low nanogram per gram level, which are well below the required limits for UE regulation compliance. Satisfactory recoveries above 80%, except for MI (mean values close to 60%), were obtained. In all cases, the method precision (% RSD) was lower than 7%, making this low cost extraction method reliable for routine control. The validated methodology was finally applied to the analysis of a wide variety of cosmetics and household products. Most of the real samples analyzed have been shown to comply with the current European Cosmetic Regulation, although the results obtained for some rinse-off cosmetics (e.g. baby care products) revealed high isothiazolinone content. PMID:23182288

  3. NATO/CCMS PILOT STUDY CLEAN PRODUCTS AND PROCESSES (PHASE 1) 1998 ANNUAL REPORT (EPA/600/R-98/065)

    EPA Science Inventory

    This annual report presents the proceedings of the first annual NATO/CCMS pilot study meeting in Cincinnati in March 1998. Guest speakers focused on efforts in the research arena of clean products, clean processes, life cycle analysis, ecolabeling, and pollution prevention tools.

  4. Final Report of NATO/SPS Pilot Study on Clean Products and Processes (Phase I and II)

    EPA Science Inventory

    Early in 1998 the NATO Committee for Challenges to Modern Society (SPS) (Science for Peace and Security) approved the Pilot Study on Clean Products and Processes for an initial period of five years. The pilot was to provide a forum for member country representatives to discuss t...

  5. Gas-phase and particulate products from the atmospheric degradation of the organothiophosphorus insecticide chlorpyrifos-methyl.

    PubMed

    Borrás, Esther; Tortajada-Genaro, Luis Antonio; Ródenas, Milagros; Vera, Teresa; Coscollá, Clara; Yusá, Vicent; Muñoz, Amalia

    2015-11-01

    The phosphorothioate structure is highly present in several organophosphorus pesticides. However, there is insufficient information about its degradation process after the release to the atmosphere and the secondary pollutants formed. Herein, the atmospheric reaction of chlorpyrifos-methyl (o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate), is described for semi-urban or rural locations. The photo-oxidation under low NOx conditions (5-55 ppbV) was reproduced in a large outdoor simulation chamber, observing a rapid degradation (lifetime<3.5 h). The formation of gaseous products and particulate matter (aerosol yield 2-8%) was monitored. The chemical composition of minor products (gaseous and particulate) was studied, identifying 15 multi-oxygenated derivatives. The most abundant products were ring-retaining molecules such as o,o-dimethyl o-(3,5,6-trichloropyridin-2-yl) phosphorothioate, dimethyl 3,5,6-trichloropyridin-2-yl phosphate, o-methyl o-(3,5,6-trichloropyridin-2-yl) hydrogen phosphorothioate, 3,5,6-trichloropyridin-2-yl dihydrogen phosphate, 3,5,6-trichloropyridin-2-ol, and 3,5,6-trichloropyridine-2,4-diol. An atmospheric degradation mechanism has been proposed based on an oxidation started with OH-nucleophilic attack to P=S bond. The results have been extrapolated to other organothiophosphorus molecules, such as malathion, parathion, diazinon and methidathion, among many others, to estimate their photo-oxidative degradation and the expected products. PMID:25548033

  6. THE GAS PHASE REACTION OF OZONE WITH 1,3-BUTADIENE: FORMATION YIELDS OF SOME TOXIC PRODUCTS. (R826236)

    EPA Science Inventory

    The formation yields of acrolein, 1,2-epoxy-3-butene and OH radicals have been measured from reaction of ozone with 1,3-butadiene at room temperature and atmosphere pressure. 1,3,5-Trimethyl benzene was added to scavenge OH radicals in measurements of product yields. In separa...

  7. APPLICATION OF SOLID PHASE MICROEXTRACTION GC/MS TO THE CHARACTERIZATION OF HYDROPHILIC DISINFECTION BY-PRODUCTS IN WATER

    EPA Science Inventory

    The U.S. Environmental Protection Agency has given high priority to research aimed at developing methods to extract hydrophilic disinfection by-products (DBPs) from drinking water. Public water supplies are treated with a variety of chemicals aimed at reducing or eliminating inf...

  8. Valeric acid induces cell cycle arrest at G1 phase in CHO cell cultures and improves recombinant antibody productivity.

    PubMed

    Park, Jin Hyoung; Noh, Soo Min; Woo, Ju Rang; Kim, Jong Won; Lee, Gyun Min

    2016-03-01

    To find a more effective chemical reagent for improved monoclonal antibody (mAb) production, eight chemical reagents (curcumin, quercein, DL-sulforaphane, thymidine, valeric acid, phenyl butyrate, valproic acid, and lithium chloride) known to induce cell cycle arrest were examined individually as chemical additives to recombinant CHO (rCHO) cell cultures producing mAb. Among these chemical additives, valeric acid showed the best production performance. Valeric acid decreased specific growth rate (μ), but increased culture longevity and specific mAb productivity (qmAb ) in a dose-dependent manner. The beneficial effect of valeric acid on culture longevity and qmAb outweighed its detrimental effect on μ, resulting in 2.9-fold increase in the maximum mAb concentration when 1.5 mM valeric acid was added to the cultures. Furthermore, valeric acid did not negatively affect the mAb quality attributes with regard to aggregation, charge variation, and galactosylation. Unexpectedly, galactosylation of the mAb increased by the 1.5 mM valeric acid addition. Taken together, the results obtained here demonstrate that valeric acid is an effective chemical reagent to increase mAb production in rCHO cells. PMID:26663903

  9. Characterization of currently marketed heparin products: reversed-phase ion-pairing liquid chromatography mass spectrometry of heparin digests.

    PubMed

    Brustkern, Adam M; Buhse, Lucinda F; Nasr, Moheb; Al-Hakim, Ali; Keire, David A

    2010-12-01

    Here we report results from the analyses by enzymatic digestion and reversed-phase ion-pairing liquid chromatography mass spectrometry (RPIP-LC-MS) of active pharmaceutical ingredient (API) unfractionated heparins (UFHs) from six different manufacturers and one USP standard sample. We employed a reverse phase ion-pairing chromatography method using a C(18) column and hexylamine as the ion-pairing reagent with acetonitrile gradient elution to separate disaccharides generated from the digestion of the heparins by lyase I and III (E.C. 4.2.2.7 and 4.2.2.8) before introduction into an ion-trap mass spectrometer by an electrospray ionization (ESI) interface. Extracted ion chromatograms (EICs) were used to determine the relative abundance of the disaccharides by mass spectrometry. Eight disaccharides were observed and a similar composition profile was observed from digests of 20 UFH samples. The compositional profile determined from these experiments provides a measure of the norm and range of variation in "good" heparin to which future preparations can be compared. Furthermore, the profile obtained in the RPIP-LC-MS assay is sensitive to the presence of the contaminant, oversulfated chondroitin sulfate A (OSCS), in heparin. PMID:21069966

  10. Comprehensive analysis of pharmaceutical products using simultaneous mixed-mode (ion-exchange/reversed-phase) and hydrophilic interaction liquid chromatography.

    PubMed

    Kazarian, Artaches A; Nesterenko, Pavel N; Soisungnoen, Phimpha; Burakham, Rodjana; Srijaranai, Supalax; Paull, Brett

    2014-08-01

    Liquid chromatographic assays were developed using a mixed-mode column coupled in sequence with a hydrophilic interaction liquid chromatography column to allow the simultaneous comprehensive analysis of inorganic/organic anions and cations, active pharmaceutical ingredients, and excipients (carbohydrates). The approach utilized dual sample injection and valve-mediated column switching and was based upon a single high-performance liquid chromatography gradient pump. The separation consisted of three distinct sequential separation mechanisms, namely, (i) ion-exchange, (ii) mixed-mode interactions under an applied dual gradient (reversed-phase/ion-exchange), and (iii) hydrophilic interaction chromatography. Upon first injection, the Scherzo SS C18 column (Imtakt) provided resolution of inorganic anions and cations under isocratic conditions, followed by a dual organic/salt gradient to elute active pharmaceutical ingredients and their respective organic counterions and potential degradants. At the top of the mixed-mode gradient (high acetonitrile content), the mobile phase flow was switched to a preconditioned hydrophilic interaction liquid chromatography column, and the standard/sample was reinjected for the separation of hydrophilic carbohydrates, some of which are commonly known excipients in drug formulations. The approach afforded reproducible separation and resolution of up to 23 chemically diverse solutes in a single run. The method was applied to investigate the composition of commercial cough syrups (Robitussin®), allowing resolution and determination of inorganic ions, active pharmaceutical ingredients, excipients, and numerous well-resolved unknown peaks. PMID:24890905

  11. Production of a metal-binding exopolysaccharide by Paenibacillus jamilae using two-phase olive-mill waste as fermentation substrate.

    PubMed

    Morillo, Jose Antonio; Aguilera, Margarita; Ramos-Cormenzana, Alberto; Monteoliva-Sánchez, Mercedes

    2006-09-01

    The present study investigated the use of two-phase olive mill waste (TPOMW) as substrate for the production of exopolysaccharide (EPS) by the endospore-forming bacilli Paenibacillus jamilae. This microorganism was able to grow and produce EPS in aqueous extracts of TPOMW as a unique source of carbon. The effects of substrate concentration and the addition of inorganic nutrients were investigated. Maximal polymer yield in 100-ml batch-culture experiments (2 g l(-1)) was obtained in cultures prepared with an aqueous extract of 20% TPOMW (w/v). An inhibitory effect was observed on growth and EPS production when TPOMW concentration was increased. Nutrient supplementation (nitrate, phosphate, and other inorganic nutrients) did not increase yield. Finally, an adsorption experiment of Pb (II), Cd (II), Cu (II), Zn (II), Co (II), and Ni (II) by EPS is reported. Lead was preferentially complexed by the polymer, with a maximal uptake of 230 mg/g EPS. PMID:16874549

  12. Performance of a novel two-phase continuously fed leach bed reactor for demand-based biogas production from maize silage.

    PubMed

    Linke, Bernd; Rodríguez-Abalde, Ángela; Jost, Carsten; Krieg, Andreas

    2015-02-01

    This study investigated the potential of producing biogas on demand from maize silage using a novel two-phase continuously fed leach bed reactor (LBR) which is connected to an anaerobic filter (AF). Six different feeding patterns, each for 1week, were studied at a weekly average of a volatile solids (VS) loading rate of 4.5 g L(-1) d(-1) and a temperature of 38°C. Methane production from the LBR and AF responded directly proportional to the VS load from the different daily feeding and resulted in an increase up to 50-60% per day, compared to constant feeding each day. The feeding patterns had no impact on VS methane yield which corresponded on average to 330 L kg(-1). In spite of some daily shock loadings, carried out during the different feeding patterns study, the reactor performance was not affected. A robust and reliable biogas production from stalky biomass was demonstrated. PMID:25479391

  13. Phase 2: Seminars to US industry of TDA feasibility study. US export potential for oil and gas suppliers to Russian production associations. Final report. Export trade information

    SciTech Connect

    Not Available

    1994-09-18

    The study was funded by the U.S. Trade and Development Agency on behalf of the Russian Production Association Varyeganneftegas Joint Stock Company (VNG JSC). It is a report Phase II of the Russian Oilfield Study, and it had two main objectives. The first was to enhance the competitiveness of the U.S. private sector in sales of oilfield equipment and services; the second goal was to assist the World Bank and VNG JSC in efforts to rehabilitate their oilfields by familiarizing VNG representatives with U.S. production and service capabilities in the petroleum sector. The report is divided into the following sections: (1) Background; (2) The Planning Stage; (3) The Implementation Stage; and (4) Conclusions.

  14. Atmospheric reactivity of hydroxyl radicals with guaiacol (2-methoxyphenol), a biomass burning emitted compound: Secondary organic aerosol formation and gas-phase oxidation products

    NASA Astrophysics Data System (ADS)

    Lauraguais, Amélie; Coeur-Tourneur, Cécile; Cassez, Andy; Deboudt, Karine; Fourmentin, Marc; Choël, Marie

    2014-04-01

    Methoxyphenols are low molecular weight semi-volatile polar aromatic compounds produced from the pyrolysis of wood lignin. The reaction of guaiacol (2-methoxyphenol) with hydroxyl radicals has been studied in the LPCA simulation chamber at (294 ± 2) K, atmospheric pressure, low relative humidity (RH < 1%) and under high-NOx conditions using CH3ONO as OH source. The aerosol production was monitored using a SMPS (Scanning Mobility Particle Sizer); the SOA yields were in the range from 0.003 to 0.87 and the organic aerosol formation can be expressed by a one-product gas/particle partitioning absorption model. Transmission (TEM) and Scanning (SEM) Electron Microscopy observations were performed to characterize the physical state of SOA produced from the OH reaction with guaiacol; they display both liquid and solid particles (in an amorphous state). GC-FID (Gas Chromatography - Flame Ionization Detection) and GC-MS (Gas Chromatography - Mass Spectrometry) analysis show the formation of nitroguaiacol isomers as main oxidation products in the gas- and aerosol-phases. In the gas-phase, the formation yields were (10 ± 2) % for 4-nitroguaiacol (1-hydroxy-2-methoxy-4-nitrobenzene; 4-NG) and (6 ± 2) % for 3- or 6-nitroguaiacol (1-hydroxy-2-methoxy-3-nitrobenzene or 1-hydroxy-2-methoxy-6-nitrobenzene; 3/6-NG; the standards are not commercially available so both isomers cannot be distinguished) whereas in SOA their yield were much lower (≤0.1%). To our knowledge, this work represents the first identification of nitroguaiacols as gaseous oxidation products of the OH reaction with guaiacol. As the reactivity of nitroguaiacols with atmospheric oxidants is probably low, we suggest using them as biomass burning emission gas tracers. The atmospheric implications of the guaiacol + OH reaction are also discussed.

  15. Direct thermal water splitting by concentrated solar radiation for hydrogen production. Phase O: Proof of concept experiment

    NASA Technical Reports Server (NTRS)

    Genequand, P.

    1980-01-01

    The direct production of hydrogen from water and solar energy concentrated into a high temperature aperture is described. A solar powered reactor able to dissociate water vapor and to separate the reaction product at high temperature was developed, and direct water splitting has been achieved in a laboratory reactor. Water vapor and radiative heating from a carbon dioxide laser are fed into the reactor, and water vapor enriched in hydrogen and water vapor enriched in oxygen are produced. The enriched water vapors are separated through a separation membrane, a small disc of zirconium dioxide heated to a range of 1800 k to 2800 k. To avoid water vapor condensation within the reactor, the total pressure within the reactor was limited to 0.15 torr. A few modifications would enable the reactor to be operated at an increased pressure of a few torrs. More substantial modifications would allow for a reaction pressure of 0.1 atmosphere.

  16. Feasibility study of wood-fired cogeneration at a Wood Products Industrial Park, Belington, WV. Phase II

    SciTech Connect

    Vasenda, S.K.; Hassler, C.C.

    1992-06-01

    Customarily, electricity is generated in a utility power plant while thermal energy is generated in a heating/cooling plant; the electricity produced at the power plant is transmitted to the heating/cooling plant to power equipments. These two separate systems waste vast amounts of heat and result in individual efficiencies of about 35%. Cogeneration is the sequential production of power (electrical or mechanical) and thermal energy (process steam, hot/chilled water) from a single power source; the reject heat of one process issued as input into the subsequent process. Cogeneration increases the efficiency of these stand-alone systems by producing these two products sequentially at one location using a small additional amount of fuel, rendering the system efficiency greater than 70%. This report discusses cogeneration technologies as applied to wood fuel fired system.

  17. Effect of straw on lamb welfare, production performance and meat quality during the finishing phase of fattening.

    PubMed

    Teixeira, D L; Miranda-de la Lama, G C; Villarroel, M; Garcia-Belenguer, S; Sañudo, C; Maria, G A

    2012-12-01

    The studies analyse the effect of straw on lamb welfare, production and meat quality in finishing lambs. Two studies were carried out. Study 1 included two treatments and two replicates with six lambs each (17.20±0.2 kg). One pen was provided with straw for forage and bedding while the other had none. Feeding with concentrate was ad libitum. Live weight and concentrate consumption were recorded and average daily gain and conversion index calculated. Stereotypes, agonistic and affiliative interactions and physiological indicators of stress were analysed. In study 2, 24 lambs were divided into two groups to analyse the effect of treatments on meat and carcass quality. No significant differences in production or meat quality traits were observed. Lambs housed without straw had higher levels of cortisol and stereotypes. Affiliative interactions were greater in lambs without straw. Results suggest that straw can be considered an effective environment-enriching tool to improve welfare. PMID:22871584

  18. Gas-phase reaction products and yields of terpinolene with ozone and nitric oxide using a new derivatization agent

    NASA Astrophysics Data System (ADS)

    Ham, Jason E.; Jackson, Stephen R.; Harrison, Joel C.; Wells, J. R.

    2015-12-01

    The new derivatization agent, O-tert-butylhydroxylamine hydrochloride (TBOX) was used to investigate the carbonyl reaction products from terpinolene ozonolysis. With ozone (O3) as the limiting reagent, four carbonyl compounds were detected: methylglyoxal (MG), 4-methylcyclohex-3-en-1-one, (4MCH), 6-oxo-3-(propan-2-ylidene) heptanal (6OPH), and 3,6-dioxoheptanal (36DOH). The tricarbonyl 36DOH has not been previously observed. Using cyclohexane as a hydroxyl radical (OHrad) scavenger, the yields of 6OPH and 36DOH were reduced indicating the influence secondary OHrad radicals have on terpinolene ozonolysis products. However, the MG yield increased and the 4MCH yield was unchanged when OHrad radicals were scavenged suggesting they are only made by the terpinolene + O3 reaction. The detection of 36DOH using TBOX highlights the advantages of a smaller molecular weight derivatization agent for the detection of multi-carbonyl compounds. The product yields from terpinolene ozonolysis experiments conducted in the presence of 20 ppb nitric oxide (NO) remained unchanged except for MG which decreased. However, in experiments where O3 was kept constant at 50 ppb and NO was varied (20, 50, 100 ppb) MG, 6OPH, 36DOH decreased with increasing NO while 4MCH increased with increasing NO. The use of TBOX derivatization if combined with other derivatization agents may address a recurring need to simply and accurately detect multi-functional oxygenated species in air.

  19. Production of stabilized Criegee intermediates and peroxides in the gas phase ozonolysis of alkenes: 2. Asymmetric and biogenic alkenes

    NASA Astrophysics Data System (ADS)

    Hasson, Alam S.; Ho, Andy W.; Kuwata, Keith T.; Paulson, Suzanne E.

    2001-12-01

    Organic hydroperoxide, hydrogen peroxide, and >C1 carbonyl yields have been measured from the reaction of a set of structurally diverse and atmospherically significant terminal and exocyclic alkenes with ozone. Product yields were investigated for 1-butene, 1-pentene, 1-octene, methylene cyclohexane, β-pinene, camphene and isoprene for humidities from 0 to 80% using gas chromatography with flame ionization detection and high-performance liquid chromatography with fluorescence detection. The yields of these products were used to estimate the following stabilized Criegee intermediate yields: 1-butene (0.27), 1-pentene (0.29), 1-octene (0.36), methylene cyclohexane (0.18), β-pinene (0.28), camphene (0.31), and isoprene (0.27). The reaction of stabilized Criegee intermediates with water produces primarily hydroxymethyl hydroperoxide from CH2OO, and H2O2 and a carbonyl compound for larger Criegee intermediates; acid formation is expected to be low. The exception is camphene, for which the large Criegee intermediate generates the corresponding hydroxyalkyl hydroperoxide in its reaction with water. These results were used to develop a structure activity relationship to estimate stabilized Criegee intermediate yields and to demonstrate that this model is consistent with literature values for OH yields from these ozone-alkene reactions. The mechanisms of the formation of these products are discussed and a hypothesis for the decrease in OH formation with increasing chain length for terminal alkenes is provided. Finally, a parameterization of the reactions for incorporation into atmospheric models is developed.

  20. Final report on the power production phase of the 10 MW/sub e/ Solar Thermal Central Receiver Pilot Plant

    SciTech Connect

    Radosevich, L.G.

    1988-03-01

    This report describes the evaluations of the power production testing of Solar One, the 10 MW/sub e/ Solar Thermal Central Receiver Pilot Plant near Barstow, California. The Pilot Plant, a cooperative project of the US Department of Energy and utility firms led by the Southern California Edison Company, began a three year period of power production operation in August 1984. During this period, plant performance indicators, such as capacity factor, system efficiency, and availability, were studied to assess the operational capability of the Pilot Plant to reliably supply electrical power. Also studied was the long-term performance of such key plant components as the heliostats and the receiver. During the three years of power production, the Pilot Plant showed an improvement in performance. Considerable increases in capacity factor, system efficiency, and availability were achieved. Heliostat operation was reliable, and only small amounts of mirror corrosion were observed. Receiver tube leaks did occur, however, and were the main cause of the plant's unscheduled outages. The Pilot Plant provided valuable lessons which will aid in the design of future solar central receiver plants. 53 refs., 46 figs., 4 tabs.

  1. Silicification of wood adopted for barrel production using pure silicon alkoxides in gas phase to avoid microbial colonisation.

    PubMed

    Guzzon, Raffaele; Widmann, Giacomo; Bertoldi, Daniela; Nardin, Tiziana; Callone, Emanuela; Nicolini, Giorgio; Larcher, Roberto

    2015-02-01

    The paper presents a new approach, covering wood with silica-based material in order to protect it from spoilage due to microbial colonisation and avoiding the loss of the natural features of the wood. Wood specimens derived from wine barrels were treated with methyltriethoxysilane in gas phase, leading to the deposition of a silica nanofilm on the surface. (29)Si and (13)C solid state Nuclear Magnetic Resonance and Scanning Electron Microscope-Energy Dispersive X-ray analysis observations showed the formation of a silica polymeric film on the wood samples, directly bonding with the wood constituents. Inductively Coupled Plasma-Mass Spectroscopy quantification of Si showed a direct correlation between the treatment time and silica deposition on the surface of the wood. The silica-coated wood counteracted colonisation by the main wine spoilage microorganisms, without altering the migration from wood to wine of 21 simple phenols measured using a HPLC-Electrochemical Coulometric Detection. PMID:25481070

  2. Production of low-density poly (4-methyl-1-pentene) foam via phase inversion from binary solvent/nonsovent systems

    SciTech Connect

    Simandl, R.F.; Robinson, D.N.; Bolinger, W.L.; Davis, W.E.

    1991-11-01

    Phase inversion from durene/naphthalene, durene/tmpdo, and durene/hexadecanol binary solvent/nonsolvent systems produced well interconnected, radiographically homogeneous, open-celled poly (4- methyl-1-pentene) or pmp foams. These foams ranged in density from 5 to 50 mg/cm{sup 2}. Foam homogeneity and casting efficiency were dependent on casting scheme, durene quality, solvent-to-nonsolvent ratio, and quench temperature. Foam density tracked linearly with dissolved-polymer content. Homogeneous, ultralow-density (5 to 6 mg/cm{sup 3}) foams were produced by using a 49/51 durene/naphthalene solvent eutectic. Foam hardness or firmness tracked somewhat linearly with foam density. Foams with densities above 20 mg/cm{sup 3} were too fragile to handle without damage.

  3. Efficient production of α-ketoglutarate in the gdh deleted Corynebacterium glutamicum by novel double-phase pH and biotin control strategy.

    PubMed

    Li, Yanjun; Sun, Lanchao; Feng, Jia; Wu, Ruifang; Xu, Qingyang; Zhang, Chenglin; Chen, Ning; Xie, Xixian

    2016-06-01

    Production of L-glutamate using a biotin-deficient strain of Corynebacterium glutamicum has a long history. The process is achieved by controlling biotin at suboptimal dose in the initial fermentation medium, meanwhile feeding NH4OH to adjust pH so that α-ketoglutarate (α-KG) can be converted to L-glutamate. In this study, we deleted glutamate dehydrogenase (gdh1 and gdh2) of C. glutamicum GKG-047, an L-glutamate overproducing strain, to produce α-KG that is the direct precursor of L-glutamate. Based on the method of L-glutamate fermentation, we developed a novel double-phase pH and biotin control strategy for α-KG production. Specifically, NH4OH was added to adjust the pH at the bacterial growth stage and NaOH was used when the cells began to produce acid; besides adding an appropriate amount of biotin in the initial medium, certain amount of additional biotin was supplemented at the middle stage of fermentation to maintain a high cell viability and promote the carbon fixation to the flux of α-KG production. Under this control strategy, 45.6 g/L α-KG accumulated after 30-h fermentation in a 7.5-L fermentor and the productivity and yield achieved were 1.52 g/L/h and 0.42 g/g, respectively. PMID:26946492

  4. Cloning of Toluene 4-Monooxygenase Genes and Application of Two-Phase System to the Production of the Anticancer Agent, Indirubin.

    PubMed

    Wongsaroj, Lampet; Sallabhan, Ratiboot; Dubbs, James M; Mongkolsuk, Skorn; Loprasert, Suvit

    2015-08-01

    Indirubin is a strong inhibitor of several eukaryotic cell signaling pathways and shows promise as a treatment for myelocytic leukemia and Alzheimer's disease. The tmoABCDEF operon, encoding the components of a novel toluene 4-monooxygenase from the paint factory soil isolate, Pseudomonas sp. M4, was cloned and expressed in Escherichia coli. E. coli::pKSR12 expressing the tmo genes was used to develop a two-phase [dioctyl phthalate (DOP)/aqueous medium] culture system that was optimized to obtain maximal yields of indirubin from the starting substrate, indole. DOP was used as the organic phase to solubilize and sequester the toxic indole substrate, making possible the use of high indole concentrations that would otherwise interfere with growth in aqueous media. A 50 % (v/v) DOP two-phase system using tryptophan medium containing 3 mM cysteine, 5 mM indole, and 1 mM isatin yielded 102.4 mg/L of indirubin with no conversion of indole to the less valuable alternate product, indigo. PMID:25779640

  5. Production of γ-cyclodextrin by Bacillus cereus cyclodextrin glycosyltransferase using extractive bioconversion in polymer-salt aqueous two-phase system.

    PubMed

    Lin, Yu Kiat; Show, Pau Loke; Yap, Yee Jiun; Ariff, Arbakariya B; Mohammad Annuar, Mohammad Suffian; Lai, Oi Ming; Tang, Teck Kim; Juan, Joon Ching; Ling, Tau Chuan

    2016-06-01

    Aqueous two-phase system (ATPS) extractive bioconversion provides a technique which integrates bioconversion and purification into a single step process. Extractive bioconversion of gamma-cyclodextrin (γ-CD) from soluble starch with cyclodextrin glycosyltransferase (CGTase, EC 2.4.1.19) enzyme derived from Bacillus cereus was evaluated using polyethylene glycol (PEG)/potassium phosphate based on ATPS. The optimum condition was attained in the ATPS constituted of 30.0% (w/w) PEG 3000 g/mol and 7.0% (w/w) potassium phosphate. A γ-CD concentration of 1.60 mg/mL with a 19% concentration ratio was recovered after 1 h bioconversion process. The γ-CD was mainly partitioned to the top phase (YT=81.88%), with CGTase partitioning in the salt-rich bottom phase (KCGTase=0.51). Repetitive batch processes of extractive bioconversion were successfully recycled three times, indicating that this is an environmental friendly and a cost saving technique for γ-CD production and purification. PMID:26702953

  6. Involvement of Pyruvate Oxidase Activity and Acetate Production in the Survival of Lactobacillus plantarum during the Stationary Phase of Aerobic Growth▿ †

    PubMed Central

    Goffin, Philippe; Muscariello, Lidia; Lorquet, Frederique; Stukkens, Aline; Prozzi, Deborah; Sacco, Margherita; Kleerebezem, Michiel; Hols, Pascal

    2006-01-01

    In addition to the previously characterized pyruvate oxidase PoxB, the Lactobacillus plantarum genome encodes four predicted pyruvate oxidases (PoxC, PoxD, PoxE, and PoxF). Each pyruvate oxidase gene was individually inactivated, and only the knockout of poxF resulted in a decrease in pyruvate oxidase activity under the tested conditions. We show here that L. plantarum has two major pyruvate oxidases: PoxB and PoxF. Both are involved in lactate-to-acetate conversion in the early stationary phase of aerobic growth and are regulated by carbon catabolite repression. A strain devoid of pyruvate oxidase activity was constructed by knocking out the poxB and poxF genes. In this mutant, acetate production was strongly affected, with lactate remaining the major end product of either glucose or maltose fermentation. Notably, survival during the stationary phase appeared to be dramatically improved in the poxB poxF double mutant. PMID:17012588

  7. Influences of TiO2 phase structures on the structures and photocatalytic hydrogen production of CuOx/TiO2 photocatalysts

    NASA Astrophysics Data System (ADS)

    Liu, Yuanxu; Wang, Zhonglei; Huang, Weixin

    2016-12-01

    CuOx/TiO2 photocatalysts employing TiO2 with different phase structures as well as P25 as supports were prepared, and their structures and activity for photocatalytic H2 production in methanol/water solution under simulated solar light were comparatively studied. Structural characterization results demonstrated that the TiO2 phase structure strongly affects the CuOx-TiO2 interaction and copper species in various CuOx/TiO2 photocatalysts. The Cu2O-rutile TiO2 interaction is much stronger than the Cu2O-anatase TiO2 interaction, facilitates the interfacial charge transfer process within the Cu2O-rutile TiO2 heterojunction but disables supported Cu2O to catalyze the hole-participated methanol oxidation. The Cu2O-anatase TiO2 heterojunction with the appropriate Cu2O-anatase TiO2 interaction and thus the balancing efficiencies between the interfacial charge transfer process and hole-participated methanol oxidation is most photocatalytic active, and CuOx/P25 with the largest population of Cu2O-anatase TiO2 heterojunction exhibits the highest photocatalytic H2 production. These results provide novel insights in the applied surface science of CuOx/TiO2 photocatalysts.

  8. Glycerol Overproduction by Engineered Saccharomyces cerevisiae Wine Yeast Strains Leads to Substantial Changes in By-Product Formation and to a Stimulation of Fermentation Rate in Stationary Phase

    PubMed Central

    Remize, F.; Roustan, J. L.; Sablayrolles, J. M.; Barre, P.; Dequin, S.

    1999-01-01

    Six commercial wine yeast strains and three nonindustrial strains (two laboratory strains and one haploid strain derived from a wine yeast strain) were engineered to produce large amounts of glycerol with a lower ethanol yield. Overexpression of the GPD1 gene, encoding a glycerol-3-phosphate dehydrogenase, resulted in a 1.5- to 2.5-fold increase in glycerol production and a slight decrease in ethanol formation under conditions simulating wine fermentation. All the strains overexpressing GPD1 produced a larger amount of succinate and acetate, with marked differences in the level of these compounds between industrial and nonindustrial engineered strains. Acetoin and 2,3-butanediol formation was enhanced with significant variation between strains and in relation to the level of glycerol produced. Wine strains overproducing glycerol at moderate levels (12 to 18 g/liter) reduced acetoin almost completely to 2,3-butanediol. A lower biomass concentration was attained by GPD1-overexpressing strains, probably due to high acetaldehyde production during the growth phase. Despite the reduction in cell numbers, complete sugar exhaustion was achieved during fermentation in a sugar-rich medium. Surprisingly, the engineered wine yeast strains exhibited a significant increase in the fermentation rate in the stationary phase, which reduced the time of fermentation. PMID:9872772

  9. SUBTASK 1.7 EVALUATION OF KEY FACTORS AFFECTING SUCCESSFUL OIL PRODUCTION IN THE BAKKEN FORMATION, NORTH DAKOTA PHASE II

    SciTech Connect

    Darren D. Schmidt; Steven A. Smith; James A. Sorensen; Damion J. Knudsen; John A. Harju; Edward N. Steadman

    2011-10-31

    Production from the Bakken and Three Forks Formations continues to trend upward as forecasts predict significant production of oil from unconventional resources nationwide. As the U.S. Geological Survey reevaluates the 3.65 billion bbl technically recoverable estimate of 2008, technological advancements continue to unlock greater unconventional oil resources, and new discoveries continue within North Dakota. It is expected that the play will continue to expand to the southwest, newly develop in the northeastern and northwestern corners of the basin in North Dakota, and fully develop in between. Although not all wells are economical, the economic success rate has been near 75% with more than 90% of wells finding oil. Currently, only about 15% of the play has been drilled, and recovery rates are less than 5%, providing a significant future of wells to be drilled and untouched hydrocarbons to be pursued through improved stimulation practices or enhanced oil recovery. This study provides the technical characterizations that are necessary to improve knowledge, provide characterization, validate generalizations, and provide insight relative to hydrocarbon recovery in the Bakken and Three Forks Formations. Oil-saturated rock charged from the Bakken shales and prospective Three Forks can be produced given appropriate stimulation treatments. Highly concentrated fracture stimulations with ceramic- and sand-based proppants appear to be providing the best success for areas outside the Parshall and Sanish Fields. Targeting of specific lithologies can influence production from both natural and induced fracture conductivity. Porosity and permeability are low, but various lithofacies units within the formation are highly saturated and, when targeted with appropriate technology, release highly economical quantities of hydrocarbons.

  10. SUPERGLASS. Engineering field tests - Phase 3. Production, market planning, and product evaluation for a high-thermal-performance insulating glass design utilizing HEAT MIRROR transparent insulation. Final report

    SciTech Connect

    Tilford, C L

    1982-11-01

    HEAT MIRROR transparent window insulation consists of a clear polyester film two mils (.002'') thick with a thin, clear low-emissivity (.15) coating deposited on one side by state-of-the-art vacuum deposition processes. This neutral-colored invisible coating reflects long-wave infrared energy (heat). When mounted by being stretched with a 1/2'' air-gap on each side of the film, the resulting unit reduces heat loss by 60% compared to dual insulating glass. Southwall Corporation produces HEAT MIRROR transparent insulation and markets it to manufacturers of sealed insulating glass (I.G.) units and window and building manufacturers who make their own I.G. These companies build and sell the SUPERGLASS sealed glazing units. Units made and installed in buildings by six customers were visited. These units were located in many geographic regions, including the Pacific Northwest, Rocky Mountains, New England, Southeast, and West Coast. As much as could be obtained of their history was recorded, as was their current condition and performance. These units had been in place from two weeks to over a year. All of the units were performing thermally very well, as measured by taking temperature profiles through them and through adjacent conventional I.G. units. Some units had minor visual defects (attributed to I.G. assembly techniques) which are discussed in detail. Overall occupant acceptance was enthusiastically positive. In addition to saving energy, without compromise of optical quality or appearance, the product makes rooms with large glazing areas comfortable to be in in cold weather. All defects observed were present when built; there appears to be no in-field degradation of quality at this time.

  11. DNA-polyfluorophore Chemosensors for Environmental Remediation: Vapor-phase Identification of Petroleum Products in Contaminated Soil†

    PubMed Central

    Jiang, Wei; Wang, Shenliang; Yuen, Lik Hang; Kwon, Hyukin; Ono, Toshikazu

    2013-01-01

    Contamination of soil and groundwater by petroleum-based products is an extremely widespread and important environmental problem. Here we have tested a simple optical approach for detecting and identifying such industrial contaminants in soil samples, using a set of fluorescent DNA-based chemosensors in pattern-based sensing. We used a set of diverse industrial volatile chemicals to screen and identify a set of five short oligomeric DNA fluorophores on PEG-polystyrene microbeads that could differentiate the entire set after exposure to their vapors in air. We then tested this set of five fluorescent chemosensor compounds for their ability to respond with fluorescence changes when exposed to headgas over soil samples contaminated with one of ten different samples of crude oil, petroleum distillates, fuels, lubricants and additives. Statistical analysis of the quantitative fluorescence change data (as Δ(R,G,B) emission intensities) revealed that these five chemosensors on beads could differentiate all ten product mixtures at 1000 ppm in soil within 30 minutes. Tests of sensitivity with three of the contaminant mixtures showed that they could be detected and differentiated in amounts at least as low as one part per million in soil. The results establish that DNA-polyfluorophores may have practical utility in monitoring the extent and identity of environmental spills and leaks, while they occur and during their remediation. PMID:23878719

  12. Engineering scale development of the vapor-liquid-solid (VLS) process for the production of silicon carbide fibrils. Phase 2

    SciTech Connect

    Ohnsorg, R.W.; Hollar, W.E. Jr.; Lau, S.K.; Ko, F.K.; Schatz, K.

    1995-04-01

    As reinforcements for composites, VLS SiC fibrils have attractive mechanical properties including high-strength, high modulus, and excellent creep resistance. To make use of their excellent mechanical properties in a composite, a significant volume fraction (>10%) of aligned, long fibrils (>2 mm) needs to be consolidated in the ceramic matrix. The fibrils must be processed into an assembly that will allow for composite fabrication while maintaining fibril alignment and length. With Advanced Product Development (APD) as the yam fabrication subcontractor, Carborundum investigated several approaches to achieve this goaL including traditional yam-forming processes such as carding and air-vortex spinning and nontraditional processes such as tape forming and wet casting. Carborundum additionally performed an economic analysis for producing 500 and 10,000 pounds of SiC fibrils annually using both conservative and more aggressive processing parameters. With the aggressive approach, the projected costs for SiC fibril production for 500 and 10,000 pounds per year are $1,340/pound and $340/pound, respectively.

  13. Assessment of underground coal gasification in bituminous coals: potential UCG products and markets. Final report, Phase I

    SciTech Connect

    1982-01-31

    The following conclusions were drawn from the study: (1) The US will continue to require new sources of energy fuels and substitutes for petrochemical feedstocks into the foreseeable future. Most of this requirement will be met using coal. However, the cost of mining, transporting, cleaning, and preparing coal, disposing of ash or slag and scrubbing stack gases continues to rise; particularly, in the Eastern US where the need is greatest. UCG avoids these pitfalls and, as such, should be considered a viable alternative to the mining of deeper coals. (2) Of the two possible product gases LBG and MBG, MBG is the most versatile. (3) The most logical use for UCG product in the Eastern US is to generate power on-site using a combined-cycle or co-generation system. Either low or medium Btu gas (LBG or MBG) can be used. (4) UCG should be an option whenever surface gasification is considered; particularly, in areas where deeper, higher sulfur coal is located. (5) There are environmental and social benefits to use of UCG over surface gasification in the Eastern US. (6) A site could be chosen almost anywhere in the Illinois and Ohio area where amenable UCG coal has been determined due to the existence of existing transportation or transmission systems. (7) The technology needs to be demonstrated and the potential economic viability determined at a site in the East-North-Central US which has commercial quantities of amenable bituminous coal before utilities will show significant interest.

  14. Reactivity of OH and CH3OH between 22 and 64 K: Modeling the Gas Phase Production of CH3O in Barnard 1b

    NASA Astrophysics Data System (ADS)

    Antiñolo, M.; Agúndez, M.; Jiménez, E.; Ballesteros, B.; Canosa, A.; El Dib, G.; Albaladejo, J.; Cernicharo, J.

    2016-05-01

    In recent years, ultra-low temperature chemical kinetic experiments have demonstrated that some gas-phase reactions are much faster than was previously thought. One example is the reaction between OH and CH3OH, which has recently been found to be accelerated at low temperatures yielding CH3O as its main product. This finding raised the question of whether or not the CH3O observed in the dense core Barnard 1b could be formed by the gas-phase reaction of CH3OH and OH. Several chemical models including this reaction and grain-surface processes have been developed to explain the observed abundance of CH3O, but they have met with little success. Here, we report for the first time the rate coefficients for the gas-phase reaction of OH and CH3OH down to a temperature of 22 K, which is very close to the temperature in cold interstellar clouds. Two independent experimental set-ups based on the supersonic gas expansion technique coupled to the pulsed laser photolysis laser-induced fluorescence technique were used to determine the rate coefficients in the temperature range 22–64 K. The temperature dependence obtained in this work can be expressed as k(22–64 K) = {(3.6+/- 0.1)× {10}-12(T/300{{K}})}-(1.0+/- 0.2) cm3 molecule‑1 s‑1. Implementing this expression in a chemical model of a cold, dense cloud results in CH3O/CH3OH abundance ratios similar to or slightly lower than the value of ∼3 × 10‑3 observed in Barnard 1b. This finding confirms that the gas-phase reaction between OH and CH3OH is an important contributor to the formation of interstellar CH3O. The role of grain-surface processes in the formation of CH3O, although it cannot be fully neglected, remains controversial.

  15. Reactivity of OH and CH3OH Between 22 and 64 K: Modelling the Gas Phase Production of CH3O in Barnard 1B

    PubMed Central

    Antiñolo, M.; Agúndez, M.; Jiménez, E.; Ballesteros, B.; Canosa, A.; Dib, G. El; Albaladejo, J.; Cernicharo, J.

    2016-01-01

    In the last years, ultra-low temperature chemical kinetic experiments have demonstrated that some gas-phase reactions are much faster than previously thought. One example is the reaction between OH and CH3OH, which has been recently found to be accelerated at low temperatures yielding CH3O as main product. This finding opened the question of whether the CH3O observed in the dense core Barnard 1b could be formed by the gas-phase reaction of CH3OH and OH. Several chemical models including this reaction and grain-surface processes have been developed to explain the observed abundance of CH3O with little success. Here we report for the first time rate coefficients for the gas-phase reaction of OH and CH3OH down to a temperature of 22 K, very close to those in cold interstellar clouds. Two independent experimental set-ups based on the supersonic gas expansion technique coupled to the pulsed laser photolysis-laser induced fluorescence technique were used to determine rate coefficients in the temperature range 22-64 K. The temperature dependence obtained in this work can be expressed as k(22-64 K) = (3.6 ± 0.1) × 10−12(T/300 K)−(1.0±0.2) cm3 molecule−1 s−1. Implementing this expression in a chemical model of a cold dense cloud results in CH3O/CH3OH abundance ratios similar or slightly lower than the value of ∼ 3 × 10−3 observed in Barnard 1b. This finding confirms that the gas-phase reaction between OH and CH3OH is an important contributor to the formation of interstellar CH3O. The role of grain-surface processes in the formation of CH3O, although it cannot be fully neglected, remains controversial. PMID:27279655

  16. Secondary limonene endo-ozonide: A major product from gas-phase ozonolysis of R-( +)-limonene at ambient temperature

    NASA Astrophysics Data System (ADS)

    Nørgaard, A. W.; Nøjgaard, J. K.; Larsen, K.; Sporring, S.; Wilkins, C. K.; Clausen, P. A.; Wolkoff, P.

    A 16 s old gas-phase ambient temperature and 1% relative humidity reaction mixture of ozone and R-limonene (ca. 1:10) was sampled on XAD-2 resin followed by pressurized liquid extraction with dichloromethane at ambient temperature. Low temperature on-column injection and gas chromatography (GC) revealed equal amounts of diastereomeric secondary endo-limonene ozonides, in addition to 4-acetyl-1-methyl-cyclohexene (AMCH), 3-isopropyl-6-oxo-heptanal (IPOH), and endo-limonene mono-epoxides. The secondary endo-limonene ozonides began to decrease at extraction temperature above 150C and were absent at 200C. Their formation was unaffected by an increase of the relative humidity to 15%. The identification of the secondary limonene ozonides was confirmed by (1) unique consecutive losses of OH and H2O2, respectively, from the protonated quasi-molecular ion in GC-chemical ionization mass spectrometry mode (isobutane), in addition to high resolution mass determination of [M-OH] and [M- H2O2] ions in EI mode; (2) comparison of mass spectral data to that of synthesized secondary endo-limonene ozonides; and (3) oxidation of dimethyl sulfide to dimethyl sulfoxide and subsequent increase of IPOH.

  17. Preparation and application of reversed phase Chromatorotor for the isolation of natural products by centrifugal preparative chromatography.

    PubMed

    Muhammad, Ilias; Samoylenko, Volodymyr; Machumi, Francis; Zakia, Mohamed Ahmed; Mohammed, Rabab; Hetta, Mona H; Gillum, Van

    2013-03-01

    A method of preparation of rotors with a reversed phase (RP) solid silica gel sorbent layer has been developed for centrifugal preparative chromatography (CPC), also known as rotational planar chromatography (RPC). The rotors consist of binder free RP solid SiO2 layers of different thicknesses packed between two supported circular glass discs and can be used in any appropriate device for centrifugal chromatography, like Chromatotron and CycloGraph. Polar and /or semi-polar compounds with close R(f) values, as well as extracts and column fractions were separated and/or purified in a preparative and/or semi-preparative scale using the RP rotors, eluted with mixtures of aqueous-based solvents. We herein report three examples of its application, using RP Chromatorotors, for the isolation of the diastereoisomeric alkaloids banistenosides I and II from Banisteriopsis caapi, saponins III and IV from Fagonia cretica, and the sesquiterpenes artemisinin (V) and artemisinic acid (VI) from Artemisia annua. PMID:23678798

  18. High-throughput downstream process development for cell-based products using aqueous two-phase systems.

    PubMed

    Zimmermann, Sarah; Gretzinger, Sarah; Schwab, Marie-Luise; Scheeder, Christian; Zimmermann, Philipp K; Oelmeier, Stefan A; Gottwald, Eric; Bogsnes, Are; Hansson, Mattias; Staby, Arne; Hubbuch, Jürgen

    2016-09-16

    As the clinical development of cell-based therapeutics has evolved immensely within the past years, downstream processing strategies become more relevant than ever. Aqueous two-phase systems (ATPS) enable the label-free, scalable, and cost-effective separation of cells, making them a promising tool for downstream processing of cell-based therapeutics. Here, we report the development of an automated robotic screening that enables high-throughput cell partitioning analysis in ATPS. We demonstrate that this setup enables fast and systematic investigation of factors influencing cell partitioning. Moreover, we examined and optimized separation conditions for the differentiable promyelocytic cell line HL-60 and used a counter-current distribution-model to investigate optimal separation conditions for a multi-stage purification process. Finally, we show that the separation of CD11b-positive and CD11b-negative HL-60 cells is possible after partial DMSO-mediated differentiation towards the granulocytic lineage. The modeling data indicate that complete peak separation is possible with 30 transfers, and >93% of CD11b-positive HL-60 cells can be recovered with >99% purity. The here described screening platform facilitates faster, cheaper, and more directed downstream process development for cell-based therapeutics and presents a powerful tool for translational research. PMID:27567679

  19. Solid-Phase Enrichment and Analysis of Azide-Labeled Natural Products: Fishing Downstream of Biochemical Pathways.

    PubMed

    Pérez, Alexander J; Wesche, Frank; Adihou, Hélène; Bode, Helge B

    2016-01-11

    Many methods have been devised over the decades to trace precursors of specific molecules in cellular environments as, for example, in biosynthesis studies. The advent of click chemistry has facilitated the powerful combination of tracing and at the same time sieving the highly complex metabolome for compounds derived from simple or complex starting materials, especially when the click reaction takes place on a solid support. While the principle of solid-phase click reactions has already been successfully applied for selective protein and peptide enrichment, the successful enrichment of much smaller primary and secondary metabolites, showing great structural diversity and undergoing many different biosynthetic steps, has seen only little development. For bacterial secondary metabolism, a far broader tolerance for "clickable" precursors was observed than in ribosomal proteinogenesis, thus making this method a surprisingly valuable tool for the tracking and discovery of compounds within the cellular biochemical network. The implementation of this method has led to the identification of several new compounds from the bacterial genera Photorhabdus and Xenorhabdus, clearly proving its power. PMID:26626278

  20. Experimental and theoretical understanding of the gas phase oxidation of atmospheric amides with OH radicals: kinetics, products, and mechanisms.

    PubMed

    Borduas, Nadine; da Silva, Gabriel; Murphy, Jennifer G; Abbatt, Jonathan P D

    2015-05-14

    Atmospheric amides have primary and secondary sources and are present in ambient air at low pptv levels. To better assess the fate of amides in the atmosphere, the room temperature (298 ± 3 K) rate coefficients of five different amides with OH radicals were determined in a 1 m(3) smog chamber using online proton-transfer-reaction mass spectrometry (PTR-MS). Formamide, the simplest amide, has a rate coefficient of (4.44 ± 0.46) × 10(-12) cm(3) molec(-1) s(-1) against OH, translating to an atmospheric lifetime of ∼1 day. N-methylformamide, N-methylacetamide and propanamide, alkyl versions of formamide, have rate coefficients of (10.1 ± 0.6) × 10(-12), (5.42 ± 0.19) × 10(-12), and (1.78 ± 0.43) × 10(-12) cm(3) molec(-1) s(-1), respectively. Acetamide was also investigated, but due to its slow oxidation kinetics, we report a range of (0.4-1.1) × 10(-12) cm(3) molec(-1) s(-1) for its rate coefficient with OH radicals. Oxidation products were monitored and quantified and their time traces were fitted using a simple kinetic box model. To further probe the mechanism, ab initio calculations are used to identify the initial radical products of the amide reactions with OH. Our results indicate that N-H abstractions are negligible in all cases, in contrast to what is predicted by structure-activity relationships. Instead, the reactions proceed via C-H abstraction from alkyl groups and from formyl C(O)-H bonds when available. The latter process leads to radicals that can readily react with O2 to form isocyanates, explaining the detection of toxic compounds such as isocyanic acid (HNCO) and methyl isocyanate (CH3NCO). These contaminants of significant interest are primary oxidation products in the photochemical oxidation of formamide and N-methylformamide, respectively. PMID:25019427

  1. Enteric methane production and greenhouse gases balance of diets differing in concentrate in the fattening phase of a beef production system.

    PubMed

    Doreau, M; van der Werf, H M G; Micol, D; Dubroeucq, H; Agabriel, J; Rochette, Y; Martin, C

    2011-08-01

    The purposes of this study were 1) to assess the effects of 3 high-concentrate diets on enteric CH(4) production, total tract digestibility, and rumen fermentation of beef cattle, and 2) to evaluate, by life cycle assessment, the potential effects of these feeding systems on the environment. Six bulls (age of 12.4 mo and BW of 417 kg at midexperiment) of the Blond d'Aquitaine breed were assigned to 3 dietary treatments in a replicated 3 × 3 Latin square design. Diets consisted of 1) 49% natural grassland hay, 41% ground corn grain, and 10% soybean meal (hay); 2) 63% corn silage, 21% ground corn grain, and 16% soybean meal (CS); and 3) 70% ground corn grain, 16% soybean meal, and 14% wheat straw (CG). Daily CH(4) emission (g/d), measured using the sulfur hexafluoride tracer technique, was similar for the hay and CS diets and was 56% greater than for the CG diet (P < 0.001). This difference between diets was maintained when CH(4) output was expressed by unit of feed intake (P < 0.001) or digested feed (P < 0.001). Gross energy intake loss as CH(4) averaged 6.9% for the hay and CS diets and 3.2% for the CG diet (P < 0.001). Organic matter intake and GE intake did not differ between diets. Organic matter digestibility was less for the hay diet than for the CS and CG diets (P=0.008). Digestibility of NDF was greatest for the hay diet, intermediate for the CS diet, and least for the CG diet (P=0.02), with ADF digestibility being similar between the hay and CS diets and greater than for the CG diet (P < 0.001). The rumen pH at 5 h postfeeding was less for animals fed the CG diet compared with those fed the other 2 diets (on average, 5.1 vs. 5.9, respectively; P < 0.001). Total CH(4) emission (enteric + manure) was least for the CG diet, whereas N(2)O and CO(2) emissions were greatest for the CG diet. Total greenhouse gas emissions were least for the CG diet when C sequestration by grasslands was not taken into account. PMID:21383032

  2. Production of hydrogen peroxide and organic peroxides in the gas phase reactions of ozone with natural alkenes

    SciTech Connect

    Simonaitis, R.; Olszyna, K.J.; Meagher, J.F.

    1991-01-01

    The formation of H{sub 2}O{sub 2} and organic peroxides in the reaction of O{sub 3} with trans-2-butene and naturally occurring alkenes has been studied using a 31 m{sup 3} reaction chamber. H{sub 2}O{sub 2} and organic peroxides were found to be products of the O{sub 3} reaction with trans-2-butene, isoprene, {alpha} and {beta}-pinene, and limonene. Water is necessary for the formation of H{sub 2}O{sub 2} and most of the H{sub 2}O{sub 2} is formed via a route that does not involve HO{sub 2} radicals. These results indicate that the reaction of O{sub 3} with natural alkenes may be a significant source of atmospheric H{sub 2}O{sub 2}, particularly in forest and rural areas.

  3. Evaporative light scattering detector in normal-phase high-performance liquid chromatography determination of FAME oxidation products.

    PubMed

    Morales, Arturo; Marmesat, Susana; Dobarganes, M Carmen; Márquez-Ruiz, Gloria; Velasco, Joaquín

    2012-09-01

    The use of an ELS detector in NP-HPLC for quantitative analysis of oxidation products in FAME obtained from oils is evaluated in this study. The results obtained have shown that the ELS detector enables the quantitative determination of the hydroperoxides of oleic and linoleic acid methyl esters as a whole, and connected in series with a UV detector makes it possible to determine both groups of compounds by difference, providing useful complementary information. The limits of detection (LOD) and quantification (LOQ) found for hydroperoxides were respectively 2.5 and 5.7 μg mL⁻¹ and precision of quantitation expressed as coefficient of variation was lower than 10%. Due to a low sensitivity the ELS detector shows limitations to determine the low contents of secondary oxidation products in the direct analysis of FAME oxidized at low or moderate temperature. Analysis of FAME samples obtained either from high linoleic sunflower oil (HLSO) or high oleic sunflower oil (HOSO) and oxidized at 80 °C showed that only ketodienes formed from methyl linoleate can be determined in samples with relatively high oxidation, being the LOD and LOQ 0.2 and 0.4 mg/g FAME, respectively, at the analytical conditions applied. The ELS detector also enabled the determination of methyl cis-9,10-epoxystearate and methyl trans-9,10-epoxystearate, which were resolved at the chromatographic conditions applied. Results showed that these compounds, which are formed from methyl oleate, were not detected in the high-linoleic sample, but occurred at non-negligible levels in the oxidized FAME obtained from HOSO. PMID:22840820

  4. Products of the gas-phase reactions of 1,3-butadiene with OH and NO{sub 3} radicals

    SciTech Connect

    Tuazon, E.C.; Alvarado, A.; Aschmann, S.M.; Atkinson, R.; Arey, J.

    1999-10-15

    1,3-Butadiene is emitted into the atmosphere from a number of sources including combustion sources and is listed in the US as a hazardous air pollutant. In the atmosphere, 1,3-butadiene reacts with OH radicals, NO{sub 3} radicals, and O{sub 3} with the dominant tropospheric removal processes being daytime reaction with the OH radical and nighttime reaction with the NO{sub 3} radical. The authors have used gas chromatography, in situ Fourier transform infrared (FT-IR) absorption spectroscopy, and in situ atmospheric pressure ionization tandem mass spectrometry (API-MS) to identify and quantify the products formed from the reactions of 1,3-butadiene with OH radicals (in the presence of NO) and NO{sub 3} radicals. Acrolein, formaldehyde, and furan were identified and quantified from the OH radical-initiated reaction, with formation yields of 0.58 {+-} 0.04, 0.62 {+-} 0.05, and 0.03--0.04, respectively. Organic nitrates were observed by FT-IR spectroscopy with an estimated yield of 0.07 {+-} 0.03, and the API-MS analyses indicated that these organic nitrates are mainly the hydroxynitrate HOCH{sub 2}CH=CHCH{sub 2}ONO{sub 2} and/or its isomers. API-MS analyses showed the formation of a hydroxycarbonyl with the formula C{sub 4}H{sub 6}O{sub 2}, attributed to HOCH{sub 2}CH=CHCHO and/or its isomers. The major products of the NO{sub 3} radical-initiated reaction were organic nitrates; the API-MS analyses indicated the formation of acrolein, 1,2-epoxy-3-butene, and unsaturated C{sub 4}-hydroxycarbonyls, hydroxynitrates, carbonyl nitrates, and nitrooxyhydroperoxides. Acrolein, HCHO, and furan were again quantified by gas chromatographic and FT-IR analyses. The data is compared with previous literature studies, and detailed reaction mechanisms are presented and discussed.

  5. A statistical model to allow the phasing out of the animal testing of demineralised bone matrix products.

    PubMed

    Murray, Samuel S; Brochmann, Elsa J; Harker, Judith O; King, Edward; Lollis, Ryan J; Khaliq, Sameer A

    2007-08-01

    Demineralised bone matrix (DBM) products are complex mixtures of proteins known to influence bone growth, turnover, and repair. They are used extensively in orthopaedic surgery, and are bioassayed in vivo prior to being used in clinical applications. Many factors contribute to the osteogenic potency of DBM, but the relative contributions of these factors, as well as the possibility of interactive effects, are not completely defined. The "gold standard" measure of the therapeutic value of DBM, the in vivo assay for ectopic bone formation, is costly, time-consuming, and involves the use of numerous animal subjects. We have measured the levels of five growth factors released by the collagenase digestion of DBM, and statistically related these levels with osteogenic potency as determined by a standard in vivo model, in order to determine which value or combination of values of growth factors best predict osteogenic activity. We conclude that the level of BMP-2 is the best single predictor of osteogenic potency, and that adding the values of other growth factors only minimally increases the predictive power of the BMP-2 measurement. A small, but significant, interactive effect between BMP-2 and BMP-7 was demonstrated. We present a statistical model based on growth factor (e.g. BMP-2) analysis that best predicts the in vivo assay score for DBM. This model allows the investigator to predict which lots of DBM are likely to exhibit in vivo bioactivity and which are not, thus reducing the need to conduct in vivo testing of insufficiently active lots of DBM. This model uses cut-point analysis to allow the user to assign an estimate of acceptable uncertainty with respect to the "gold standard" test. This procedure will significantly reduce the number of animal subjects used to test DBM products. PMID:17850186

  6. Solar production of intermediate temperature process heat. Phase I design. Final report. [For sugarcane processing plant in Hawaii

    SciTech Connect

    1980-08-01

    This report is the final effort in the Phase I design of a solar industrial process heat system for the Hilo Coast Processing Company (HCPC) in Pepeekeo, Hawaii. The facility is used to wash, grind and extract sugar from the locally grown sugarcane and it operates 24 hours a day, 305 days per year. The major steam requirements in the industrial process are for the prime movers (mill turbines) in the milling process and heat for evaporating water from the extracted juices. Bagasse (the fibrous residue of milled sugarcane) supplied 84% of the fuel requirement for steam generation in 1979, while 65,000 barrels of No. 6 industrial fuel oil made up the remaining 16%. These fuels are burned in the power plant complex which produces 825/sup 0/F, 1,250 psi superheated steam to power a turbogenerator set which, in addition to serving the factory, generates from 7 to 16 megawatts of electricity that is exported to the local utility company. Extracted steam from the turbo-generator set supplies the plant's process steam needs. The system consists of 42,420 ft./sup 2/ of parabolic trough, single axis tracking, concentrating solar collectors. The collectors will be oriented in a North-South configuration and will track East-West. A heat transfer fluid (Gulf Synfluid 4cs) will be circulated in a closed loop fashion through the solar collectors and a series of heat exchangers. The inlet and outlet fluid temperatures for the collectors are 370/sup 0/F and 450/sup 0/F respectively. It is estimated that the net useable energy delivered to the industrial process will be 7.2 x 10/sup 9/ Btu's per year. With an HCPC boiler efficiency of 78% and 6.2 x 10/sup 6/ Btu's per barrel of oil, the solar energy system will displace 1489 barrels of oil per year. (WHK)

  7. Production of Seamless Superconducting Radio Frequency Cavities from Ultra-fine Grained Niobium, Phase II Final Report

    SciTech Connect

    Roy Crooks, Ph.D., P.E.

    2009-10-31

    The positron and electron linacs of the International Linear Collider (ILC) will require over 14,000, nine-cell, one meter length, superconducting radio frequency (SRF) cavities [ILC Reference Design Report, 2007]. Manufacturing on this scale will benefit from more efficient fabrication methods. The current methods of fabricating SRF cavities involve deep drawing of the halves of each of the elliptical cells and joining them by high-vacuum, electron beam welding, with at least 19 circumferential welds per cavity. The welding is costly and has undesirable effects on the cavity surfaces, including grain-scale surface roughening at the weld seams. Hydroforming of seamless tubes avoids welding, but hydroforming of coarse-grained seamless tubes results in strain-induced surface roughening. Surface roughness limits accelerating fields, because asperities prematurely exceed the critical magnetic field and become normal conducting. This project explored the technical and economic feasibility of an improved processing method for seamless tubes for hydroforming. Severe deformation of bulk material was first used to produce a fine structure, followed by extrusion and flow-forming methods of tube making. Extrusion of the randomly oriented, fine-grained bulk material proceeded under largely steady-state conditions, and resulted in a uniform structure, which was found to be finer and more crystallographically random than standard (high purity) RRR niobium sheet metal. A 165 mm diameter billet of RRR grade niobium was processed into five, 150 mm I.D. tubes, each over 1.8 m in length, to meet the dimensions used by the DESY ILC hydroforming machine. Mechanical properties met specifications. Costs of prototype tube production were approximately twice the price of RRR niobium sheet, and are expected to be comparable with economies of scale. Hydroforming and superconducting testing will be pursued in subsequent collaborations with DESY and Fermilab. SRF Cavities are used to construct

  8. Stability of catechins in green tea nutraceutical products: application of solid phase extraction-thin layer chromatography densitometry.

    PubMed

    Abd-Elsalam, Heba-Alla H; Al-Ghobashy, Medhat A; Zaazaa, Hala E; Ibrahim, Mohamed A

    2014-08-01

    Epigallocatechin gallate (EGCG) is a powerful antioxidant and commonly used nutraceutical. Accelerated stability of EGCG in tablet formulations was investigated. LLE and SPE were employed for sample clean-up and enrichment of EGCG over caffeine. Samples were analysed after spiking with fixed concentration of gallic acid (GA), in order to verify reproducibility of analysis. A TLC-densitometric assay was developed and validated for determination of % loss EGCG. EGCG, GA and caffeine were resolved with Rf values 0.54, 0.69 and 0.80, respectively. LC-MS/MS was used to verify identity and purity of the EGCG band. Determination was carried out over a concentration range of 0.50-5.00μg/band and 0.20-2.40μg/band for GA and caffeine, respectively. Results showed significant reduction in EGCG content after one, three and six months: 24.00%, 28.00% and 52.00% respectively. Results continue to demonstrate that stability of nutraceutical products should be investigated in-depth using industry-oriented protocols before granting marketing authorisation. PMID:24629943

  9. Isomer-specific product detection of gas-phase xylyl radical rearrangement and decomposition using VUV synchrotron photoionization.

    PubMed

    Hemberger, Patrick; Trevitt, Adam J; Gerber, Thomas; Ross, Edward; da Silva, Gabriel

    2014-05-22

    Xylyl radicals are intermediates in combustion processes since their parent molecules, xylenes, are present as fuel additives. In this study we report on the photoelectron spectra of the three isomeric xylyl radicals and the subsequent decomposition reactions of the o-xylyl radical, generated in a tubular reactor and probed by mass selected threshold photoelectron spectroscopy and VUV synchrotron radiation. Franck-Condon simulations are applied to augment the assignment of elusive species. Below 1000 K, o-xylyl radicals decompose by hydrogen atom loss to form closed-shell o-xylylene, which equilibrates with benzocyclobutene. At higher temperatures relevant to combustion engines, o-xylylene generates styrene in a multistep rearrangement, whereas the p-xylylene isomer is thermally stable, a key point of difference in the combustion of these two isomeric fuels. Another striking result is that all three xylyl isomers can generate p-xylylene upon decomposition. In addition to C8H8 isomers, phenylacetylene and traces of benzocyclobutadiene are observed and identified as further reaction products of o-xylylene, while there is also some preliminary evidence for benzene and benzyne formation. The experimental results reported here are complemented by a comprehensive theoretical C8H8 potential energy surface, which together with the spectroscopic assignments can explain the complex high-temperature chemistry of o-xylyl radicals. PMID:24679132

  10. Effect of Production Phase on Growth, Enzyme Activities and Feed Selection of Broilers Raised on Vegetable Protein Diet

    PubMed Central

    Hossain, M. A.; Islam, A. F.; Iji, P. A.

    2014-01-01

    This study consisted of two experiments, conducted to assess the impact of phase at which vegetable protein (VP) diets are introduced to broiler chicks, and preference of birds for diets based on soybean or canola meal (CM). Two hundred and ten day-old Cobb 500 chicks were randomly distributed into five dietary groups in the main experiment. One group was fed on animal protein (AP) diet all through to 21 days of age; two other groups were started on AP diet for 7 days and then switched to diets containing soybean meal (AP-SBM) or AP-CM, while two other diets (SBM-AP and CM-AP) were started on one of the VP diets for 7 days and then switched to AP diet. A sub-experiment on thirty birds raised on a commercial diet to 7 days was used in a feed selection test to quantify the preference of birds for the diets containing mainly CM or SBM. Chicks were reared under similar care and management conditions and the diets were iso-caloric and iso-nitrogenous. Results of the main experiment showed that chicks on CM-AP diet ate more (p<0.05) than those on the other diets up to day 7. Body weight gain was highest (p<0.001) on the AP-SBM diet while birds on the CM-AP diet weighed the least at 7 d. Feed intake, body weight gain, feed conversion ratio, mortality, bone growth, visceral organ development, and activities of digestive enzymes were similar between the groups from hatch to 21 days of age. Results of the second sub-experiment showed that chicks preferred the CM-based diets to the SBM-based diets at 8 to 14 d (p<0.001) and 15 to 21 d (p<0.01) when given a choice. Overall, the birds were not affected by the nature of the starter diet although they tended to prefer the canola to soybean diets. PMID:25358319

  11. Monitoring Domoic Acid production by Solid Phase Adsorption Toxin Tracking off the Santa Cruz Municipal Warf, Santa Cruz, California

    NASA Astrophysics Data System (ADS)

    Nolan, M.; Ziccarelli, L.; Kudela, R. M.

    2013-12-01

    Certain species of the diatom genus Pseudo-nitzschia are producers of the neurotoxin, domoic acid (DA). DA is known to cause amnesic shellfish poisoning also known as domoic acid poisoning, which can lead to permanent brain damage in humans and marine mammals. DA accumulates at higher trophic levels, generally due to consumption of toxic cells or through trophic transfer, and can potentially cause death of both humans and marine wildlife. The Santa Cruz Municipal Warf experiences periodic rises in DA concentrations, which can reach toxic levels in shellfish, fish, and other marine organisms. While these increases in toxicity often occur during Pseudo-nitzschia blooms, several periods of elevated DA have occurred when diatom abundance is restricted and/or dominated by non-toxic species, and there is increasing evidence that DA dissolved in seawater may be prevalent. One theory suggests that senescent or dead Pseudo-nitzschia cells sink to the benthos while retaining their toxin and are buried in sediment following the death of a bloom. Therefore, DA may accumulate in the benthos, where it is eventually released during storms or wave and tide conditions that disturb the sediment. We sampled DA in situ using Solid Phase Adsorption Toxin Tracking (SPATT) bags SPATT uses a synthetic resin to capture dissolved DA, allowing for the determination of integrated DA concentrations at known time intervals. The alternative method is mussel biotoxin monitoring, but it is less accurate due to uncertainties in the time of DA accumulation within the mussel, and the lack of uptake of dissolved DA by the mussel. We deployed and collected SPATT off the Santa Cruz Municipal Wharf at multiple depths beginning in February 2013. We expect to see increasing DA following the death of a harmful algal bloom. Under pre-bloom conditions, little to no DA has been detected in mussels or surface SPATT, but DA from SPATT is frequently observed at depth, suggesting that the sediment is exposed to

  12. A tobacco-free world: a call to action to phase out the sale of tobacco products by 2040.

    PubMed

    Beaglehole, Robert; Bonita, Ruth; Yach, Derek; Mackay, Judith; Reddy, K Srinath

    2015-03-14

    The time has come for the world to acknowledge the unacceptability of the damage being done by the tobacco industry and work towards a world essentially free from the sale (legal and illegal) of tobacco products. A tobacco-free world by 2040, where less than 5% of the world's adult population use tobacco, is socially desirable, technically feasible, and could become politically practical. Three possible ways forward exist: so-called business-as-usual, with most countries steadily implementing the WHO Framework Convention on Tobacco Control (FCTC) provisions; accelerated implementation of the FCTC by all countries; and a so-called turbo-charged approach that complements FCTC actions with strengthened UN leadership, full engagement of all sectors, and increased investment in tobacco control. Only the turbo-charged approach will achieve a tobacco-free world by 2040 where tobacco is out of sight, out of mind, and out of fashion--yet not prohibited. The first and most urgent priority is the inclusion of an ambitious tobacco target in the post-2015 sustainable development health goal. The second priority is accelerated implementation of the FCTC policies in all countries, with full engagement from all sectors including the private sector--from workplaces to pharmacies--and with increased national and global investment. The third priority is an amendment of the FCTC to include an ambitious global tobacco reduction goal. The fourth priority is a UN high-level meeting on tobacco use to galvanise global action towards the 2040 tobacco-free world goal on the basis of new strategies, new resources, and new players. Decisive and strategic action on this bold vision will prevent hundreds of millions of unnecessary deaths during the remainder of this century and safeguard future generations from the ravages of tobacco use. PMID:25784348

  13. Comparison of production-phase environmental impact metrics derived at the farm- and national-scale for United States agricultural commodities

    NASA Astrophysics Data System (ADS)

    Costello, Christine; Xue, Xiaobo; Howarth, Robert W.

    2015-11-01

    Agricultural production is critical for human survival and simultaneously contributes to ecosystem degradation. There is a need for transparent, rapid methods for evaluating the environmental impacts of agricultural production at the system-level in order to develop sustainable food supplies. We have developed a method for estimating the greenhouse gas (GHG), land use and reactive nitrogen inputs associated with the agricultural production phase of major crop and livestock commodities produced in the United States (US). Materials flow analysis (MFA) and life cycle assessment (LCA) techniques were applied to national inventory datasets. The net anthropogenic nitrogen inputs (NANI) toolbox served as the primary accounting tool for LCA and MFA. NANI was updated to create links between nitrogen fertilizer and nitrogen fixation associated with feed crops and animal food commodities. Results for the functional units kilogram (kg) of product and kg of protein for 2002 data fall within ranges of published LCA results from farm-scale studies across most metrics. Exceptions include eutrophication potential for milk and GHGs for chicken and eggs, these exceptions arise due to differing methods and boundary assumptions; suggestions for increasing agreement are identified. Land use for livestock commodities are generally higher than reported by other LCA studies due to the inclusion of all land identified as pasture or grazing land in the US in this study and given that most of the estimates from other LCAs were completed in Europe where land is less abundant. The method provides a view of the entire US agricultural system and could be applied to any year using publically available data. Additionally, utilizing a top-down approach reduces data collection and processing time making it possible to develop environmental inventory metrics rapidly for system-level decision-making.

  14. Atmospheric deposition—Another source of nutrients enhancing primary productivity in the eastern tropical Indian Ocean during positive Indian Ocean Dipole phases

    NASA Astrophysics Data System (ADS)

    Siswanto, Eko

    2015-07-01

    This study used in situ and multisensor satellite data and combinations of various primary productivity (PP) and surface nitrate models to assess the contributions of upwelling and atmospheric deposition to modulating PP in the eastern tropical Indian Ocean (ETIO) during positive phases of the Indian Ocean Dipole (+IOD). Surprisingly, atmospheric deposition of nutrients from wildfires accounted for a higher portion of enhanced PP during +IODs than wind-driven nutrient upwelling. Substantial atmospheric nutrient deposition likely also maintains high PP postupwelling and postwildfire. Multiple regression analysis further supported the importance of atmospheric deposition in determining ETIO PP with a significantly large partial regression coefficient for aerosol optical thickness. It is possible that aerosols from major wildfire areas worldwide contribute nutrients that also nontrivially modulate PP in the oceans' main upwelling systems.

  15. Detection of VX contamination in soil through solid-phase microextraction sampling and gas chromatography/mass spectrometry of the VX degradation product bis(diisopropylaminoethyl)disulfide.

    PubMed

    Hook, Gary L; Kimm, Gregory; Koch, David; Savage, Paul B; Ding, Bangwei; Smith, Philip A

    2003-04-11

    A solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) sampling and analysis method was developed for bis(diisopropylaminoethyl)disulfide (a degradation product of the nerve agent VX) in soil. A 30-min sampling time with a polydimethylsiloxane-coated fiber and high temperature alkaline hydrolysis allowed detection with 1.0 microg of VX spiked per g of agricultural soil. The method was successfully used in the field with portable GC-MS instrumentation. This method is relatively rapid (less than 1 h), avoids the use of complex preparation steps, and enhances analyst safety through limited use of solvents and decontamination of the soil before sampling. PMID:12735457

  16. Fuel and fission product behaviour in early phases of a severe accident. Part II: Interpretation of the experimental results of the PHEBUS FPT2 test

    NASA Astrophysics Data System (ADS)

    Dubourg, R.; Barrachin, M.; Ducher, R.; Gavillet, D.; De Bremaecker, A.

    2014-10-01

    One objective of the FPT2 test of the PHEBUS FP Program was to study the degradation of an irradiated UO2 fuel bundle and the fission product behaviour under conditions of low steam flow. The results of the post-irradiation examinations (PIE) at the upper levels (823 mm and 900 mm) of the test section previously reported are interpreted in the present paper. Solid state interactions between fuel and cladding have been compared with the characteristics of interaction identified in the previous separate-effect tests. Corium resulting from the interaction between fuel and cladding was formed. The uranium concentration in the corium is compared to analytical tests and a scenario for the corium formation is proposed. The analysis showed that, despite the rather low fuel burn up, the conditions of temperature and oxygen potential reached during the starvation phase are able to give an early very significant release fraction of caesium. A significant part (but not all) of the molybdenum was segregated at grain boundaries and trapped in metallic inclusions from which they were totally removed in the final part of the experiment. During the steam starvation phase, the conditions of oxygen potential were favourable for the formation of simple Ba and BaO chemical forms but the temperature was too low to provoke their volatility. This is one important difference with out-of-pile experiments such as VERCORS for which only a combination of high temperature and low oxygen potential induced a significant barium release. Finally another significant difference with analytical out-of-pile experiments comes from the formation of foamy zones due to the fission gas presence in FPT2-type experiments which give an additional possibility for the formation of stable fission product compounds.

  17. A half-century of production-phase greenhouse gas emissions from food loss & waste in the global food supply chain.

    PubMed

    Porter, Stephen D; Reay, David S; Higgins, Peter; Bomberg, Elizabeth

    2016-11-15

    Research on loss & waste of food meant for human consumption (FLW) and its environmental impact typically focuses on a single or small number of commodities in a specific location and point in time. However, it is unclear how trends in global FLW and potential for climate impact have evolved. Here, by utilising the Food and Agriculture Organization's food balance sheet data, we expand upon existing literature. Firstly, we provide a differentiated (by commodity, country and supply chain stage) bottom-up approach; secondly, we conduct a 50-year longitudinal analysis of global FLW and its production-phase greenhouse gas (GHG) emissions; and thirdly, we trace food wastage and its associated emissions through the entire food supply chain. Between 1961 and 2011 the annual amount of FLW by mass grew a factor of three - from 540Mt to 1.6Gt; associated production-phase (GHG) emissions more than tripled (from 680Mt to 2.2Gt CO2e). A 44% increase in global average per capita FLW emissions was also identified - from 225kg CO2e in 1961 to 323kg CO2e in 2011. The regional weighting within this global average changing markedly over time; in 1961 developed countries accounted for 48% of FLW and less than a quarter (24%) in 2011. The largest increases in FLW-associated GHG emissions were from developing economies, specifically China and Latin America - primarily from increasing losses in fruit and vegetables. Over the period examined, cumulatively such emissions added almost 68Gt CO2e to the atmospheric GHG stock; an amount the rough equivalent of two years of emissions from all anthropogenic sources at present rates. Building up from the most granular data available, this study highlights the growth in the climate burden of FLW emissions, and thus the need to improve efficiency in food supply chains to mitigate future emissions. PMID:27432722

  18. Technical and economic assessment of processes for the production of butanol and acetone. Phase two: analysis of research advances. Energy Conversion and Utilization Technologies Program

    SciTech Connect

    1984-08-01

    The initial objective of this work was to develop a methodology for analyzing the impact of technological advances as a tool to help establish priorities for R and D options in the field of biocatalysis. As an example of a biocatalyzed process, butanol/acetone fermentation (ABE process) was selected as the specific topic of study. A base case model characterizing the technology and economics associated with the ABE process was developed in the previous first phase of study. The project objectives were broadened in this second phase of work to provide parametric estimates of the economic and energy impacts of a variety of research advances in the hydrolysis, fermentation and purification sections of the process. The research advances analyzed in this study were based on a comprehensive literature review. The six process options analyzed were: continuous ABE fermentaton; vacuum ABE fermentation; Baelene solvent extraction; HRI's Lignol process; improved prehydrolysis/dual enzyme hydrolysis; and improved microorganism tolerance to butanol toxicity. Of the six options analyzed, only improved microorganism tolerance to butanol toxicity had a significant positive effect on energy efficiency and economics. This particular process option reduced the base case production cost (including 10% DCF return) by 20% and energy consumption by 16%. Figures and tables.

  19. Effects of Nereis diversicolor on the transformation of 1-methylpyrene and pyrene: transformation efficiency and identification of phase I and II products.

    PubMed

    Malmquist, Linus M V; Christensen, Jan H; Selck, Henriette

    2013-05-21

    Transformation of nonsubstituted and alkyl-substituted polycyclic aromatic hydrocarbons (PAHs) by the benthic invertebrate Nereis diversicolor was compared in this study. Pyrene and 1-methylpyrene were used as model compounds for nonsubstituted and alkyl-substituted PAHs, respectively. Qualitative and quantitative analyses of metabolites and parent compounds in worm tissue, water, and sediment were performed. Transformation of 1-methylpyrene generated the benzylic hydroxylated phase I product, 1-pyrenecarboxylic acid that comprised 90% of the total metabolites of 1-methylpyrene, and was mainly found in water extracts. We tentatively identified 1-methylpyrene glucuronides and 1-carbonylpyrene glycine as phase II metabolites not previously reported in literature. Pyrene was biotransformed to 1-hydroxypyrene, pyrene-1-sulfate, pyrene-1-glucuronide, and pyrene glucoside sulfate, with pyrene-1-glucuronide as the most prominent metabolite. Transformation of 1-methylpyrene (21% transformed) was more than 3 times as efficient as pyrene transformation (5.6% transformed). Because crude oils contain larger amounts of C₁-C₄-substituted PAHs than nonsubstituted PAHs, the rapid and efficient transformation of sediment-associated 1-methylpyrene may result in a high exposure of water-living organisms to metabolites of alkyl-substituted PAHs, whose toxicities are unknown. This study demonstrates the need to consider fate and effects of substituted PAHs and their metabolites in risk assessments. PMID:23611659

  20. Development of a Commercial Process for the Production of Silicon Carbide Fibrils - Draft Phase II Final Report

    SciTech Connect

    Nixdorf, RD

    2002-10-24

    hydrochloric acid. Experimental results and scanning electron microscopy of the Fibril products are presented. Future work to improve on these results is discussed.

  1. The Production and Export of Bioavailable Iron from Ice Sheets - the Importance of Colloidal and Nanoparticulate Phases

    NASA Astrophysics Data System (ADS)

    Hawkings, J.; Wadham, J. L.; Tranter, M.; Raiswell, R.; Benning, L. G.; Statham, P. J.; Tedstone, A.; Nienow, P. W.; Telling, J.; Bagshaw, E.

    2013-12-01

    Glaciers cover approximately 10% of the world's land surface at present, but our knowledge of biogeochemical processes occurring beneath them is still limited, as is our understanding of their impact on downstream ecosystems via the export of nutrients in runoff. Recent work has suggested that glaciers are a primary source of nutrients to near coastal areas(1). For example, macronutrients, such as nitrogen and phosphorus, and micronutrients, such as iron, may support primary production(2,3). Nutrient limitation of primary producers is known to be prevalent in large sectors of the world's oceans and iron is a significant limiting nutrient in Polar waters(4,5). Significantly, large oceanic algal blooms have been observed in polar areas where glacial influence is large(6,7). Our knowledge of iron speciation, concentrations and export dynamics in glacial meltwater is limited due, in part, to problems associated with collecting trace measurements in remote field locations. For example, recent work has indicated large uncertainty in 'dissolved' meltwater iron concentrations (0.2 - 4000 μM(8,9)). There is currently a dearth of information about labile nanoparticulate iron in glacial meltwaters, as well as export dynamics from large ice sheet catchments. Existing research has focused on small catchment examples(8,10), which behave differently to larger catchments(11). Presented here is the first time series of daily variations in meltwater iron concentrations (dissolved, filterable colloidal/nanoparticulate and bioavailable suspended sediment bound) from two large contrasting glacial catchments in Greenland over the 2012 and 2013 summer melt seasons. We also present the first estimates of iron concentrations in Greenlandic icebergs, which have been identified as hot spots of biological activity in the open ocean(12,13). Budgets for ice sheets based on our data demonstrate the importance of glaciers in global nutrient cycles, and reveal a large and previously under

  2. Determination of dyes in cosmetic products by micro-matrix solid phase dispersion and liquid chromatography coupled to tandem mass spectrometry.

    PubMed

    Guerra, Eugenia; Celeiro, Maria; Lamas, J Pablo; Llompart, Maria; Garcia-Jares, Carmen

    2015-10-01

    A simple method based on micro-matrix solid phase dispersion (MSPD) followed by liquid chromatography-mass spectrometry (LC-MS/MS) has been developed for the rapid and simultaneous determination of nine regulated water-soluble dyes in personal care and decorative products. The proposed miniaturized extraction procedure was optimized by means of experimental designs in order to obtain the highest extraction efficiency. Under the optimal selected conditions, the method was validated showing satisfactory performance in terms of linearity, sensitivity, and intra-day and inter-day precision. Recoveries were evaluated in different cosmetic matrices and they can be considered quantitative with average values between 70 and 120% with relative standard deviations (RSD) lower than 15%. Finally, the validated method was applied to 24 samples of cosmetic and personal care products, including decorative makeup, lipsticks, lip gloss, toothpastes, regenerating creams, shampoos, and eye shadows, among others, to cover a broad range of commercial real samples. Seven of the analyzed dyes were detected, being declared all of them in the label list of ingredients. More than 50% of the samples contained at least two dyes. Tartrazine was the most frequently found (50% of the samples) at concentration levels of 0.243-79.9μgg(-1). Other targets were found in 1-9 samples, highlighting the presence of Quinoline at high concentration (>500μgg(-1)) in a toothpaste sample. PMID:26363949

  3. Production of xylitol and tetrahydrofurfuryl alcohol from xylan in napier grass by a hydrothermal process with phosphorus oxoacids followed by aqueous phase hydrogenation.

    PubMed

    Takata, Eri; Tsuruoka, Tatsushi; Tsutsumi, Ken; Tsutsumi, Yuji; Tabata, Kenji

    2014-09-01

    The production of xylitol and tetrahydrofurfuryl alcohol (THFA) from napier grass was studied using two steps: a hydrothermal process with phosphorus oxoacids followed by aqueous phase hydrogenation with Pd/C. Xylose obtained from the napier grass by the hydrothermal treatment with 3.0 wt% phosphorous acid was subsequently converted into xylitol at 51.6% yield of the xylan in napier grass by hydrogenation with 5.0 wt% Pd/C. The furfural produced from napier grass with a 3.0 wt% phosphoric acid treatment was also directly subjected to the hydrogenation as a hydrolysate to yield 41.4% THFA based on the xylan in napier grass. The yields of xylitol and THFA obtained by hydrogenation using the napier grass hydrolysate containing xylose or furfural were almost the same as those of hydrogenation using commercial materials. To our knowledge, this is the first report on the production of THFA in high yield by hydrogenation directly from biomass hydrolysate. PMID:24971947

  4. Magnetic Graphene-Dispersive Solid-Phase Extraction for Preconcentration and Determination of Lead and Cadmium in Dairy Products and Water Samples.

    PubMed

    Ezoddin, M; Majidi, B; Abdi, K; Lamei, N

    2015-12-01

    A magnetic-dispersive solid-phase extraction (MDSPE) was used for precocentration of Pb(II) and Cd(II) in milk, yoghurt and water samples. An appropriate amount of suspension containing the magnetic graphene and Triton X-114 was injected rapidly into the aqueous sample by a syringe. Triton X-114 was used to achieve stable suspension of graphene in solution. The structure of the resulting products was confirmed by Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD) spectrometry. The effects of various parameters were studied. A detection limit of 0.16 and 0.50 µg L(-1) for Cd(II) and Pb(II) was obtained, respectively. The relative standard deviations (RSDs, n = 10) of 50 µg L(-1) of Pb and Cd were 3.3 % and 2.1 %, respectively. The results indicated that the present method can be reliably used for determination of Pb(II) and Cd(II) in dairy products and water samples with good recoveries. PMID:26438176

  5. Application of a Three-Dimensional Microstructure Evolution Model to Identify Key Process Settings for the Production of Dual-Phase Steels

    NASA Astrophysics Data System (ADS)

    Bos, C.; Mecozzi, M. G.; Hanlon, D. N.; Aarnts, M. P.; Sietsma, J.

    2011-12-01

    During the production of dual-phase (DP) steels, many transformation phenomena occur, each of which may significantly influence the final properties of the product. In the continuous annealing line, recovery, recrystallization, carbide dissolution, austenite formation, ferrite formation, and martensite formation may all occur. These processes can strongly influence each other. Furthermore, these processes may overlap. This metallurgical complexity makes both establishing the root cause of property variations and the design of new chemistries experimentally expensive and time consuming. With the recent introduction of a computationally efficient three-dimensional (3-D) microstructure evolution model that describes all transformation processes that occur during the processing of DP steels, a tool has become available to study in detail the effect of individual process parameters on the final microstructure. The model has been applied to study the transformation processes on the run-out table of the hot strip mill and in the continuous annealing line. In this study, emphasis has been placed on the role the hot-rolled microstructure plays in the final DP microstructure. Therefore, the model was extended to include the influence of manganese segregation on band formation. Details of the model and findings on the relation between the final microstructure and process settings are presented.

  6. Low-temperature synthesis of zeolite from perlite waste — Part I: review of methods and phase compositions of resulting products

    NASA Astrophysics Data System (ADS)

    Król, Magdalena; Morawska, Justyna; Mozgawa, Włodzimierz; Pichór, Waldemar

    2014-09-01

    In this paper a review of the recent studies on the synthesis of zeolites from expanded perlite under hydrothermal conditions is presented. Attention is paid to possible outcomes of synthesis from low cost glass material, such as perlite. The study also investigates the phase composition of zeolitic materials obtained by modification of by-product derived from an expanded perlite production process. The synthesis was made using the hydrothermal method with sodium hydroxide under autogenous pressure at a temperature below 100 °C for 1 to 72 h. It was possible to obtain a zeolitic material at a temperature as low as 60 °C using 4.0 M NaOH. The X-ray diffraction pattern showed the biggest peak intensity of zeolite X with 4.0 M NaOH at the temperature of 70 °C. During synthesis at higher temperature zeolite Na-P1 (with 3.0 M NaOH at 90 °C) and hydroxysodalite (with 5.0 M NaOH at 90 °C) were obtained.

  7. Evaluation of solid-phase micro-extraction coupled to gas chromatography-mass spectrometry for the headspace analysis of volatile compounds in cocoa products.

    PubMed

    Ducki, Sylvie; Miralles-Garcia, Javier; Zumbé, Albert; Tornero, Antonio; Storey, David M

    2008-02-15

    The aroma profile of cocoa products was investigated by headspace solid-phase micro-extraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS). SPME fibers coated with 100 microm polydimethylsiloxane coating (PDMS), 65 microm polydimethylsiloxane/divinylbenzene coating (PDMS-DVB), 75 microm carboxen/polydimethylsiloxane coating (CAR-PDMS) and 50/30 microm divinylbenzene/carboxen on polydimethylsiloxane on a StableFlex fiber (DVB/CAR-PDMS) were evaluated. Several extraction times and temperature conditions were also tested to achieve optimum recovery. Suspensions of the samples in distilled water or in brine (25% NaCl in distilled water) were investigated to examine their effect on the composition of the headspace. The SPME fiber coated with 50/30 microm DVB/CAR-PDMS afforded the highest extraction efficiency, particularly when the samples were extracted at 60 degrees C for 15 min under dry conditions with toluene as an internal standard. Forty-five compounds were extracted and tentatively identified, most of which have previously been reported as odor-active compounds. The method developed allows sensitive and representative analysis of cocoa products with high reproducibility. Further research is ongoing to study chocolate making processes using this method for the quantitative analysis of volatile compounds contributing to the flavor/odor profile. PMID:18371766

  8. Determination of polybrominated diphenyl ethers and polychlorinated biphenyls in fishery and aquaculture products using sequential solid phase extraction and large volume injection gas chromatography/tandem mass spectrometry.

    PubMed

    Lu, Dasheng; Lin, Yuanjie; Feng, Chao; Wang, Dongli; Qiu, Xinlei; Jin, Yu'e; Xiong, Libei; Jin, Ying; Wang, Guoquan

    2014-01-15

    A new method was developed to determine polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in fishery and aquaculture products. Samples were extracted by an accelerated solvent extraction system and cleaned up by sequential solid phase extraction (SPE) including dispersive SPE (D-SPE) and tandem SPE. PBDEs and PCBs were analyzed by a large-volume injection gas chromatography triple quadrupole mass spectrometry (LVI-GC-QqQ-MS/MS). Good linearity (R(2)≥0.9958) was achieved. Method detection limits (MDLs) were 0.16-3.3pgg(-1) (wet weight, ww) for PBDEs and 0.13-0.97pgg(-1)ww for PCBs. Mean recoveries were 60-140% with relative standard deviations (RSDs) of less than 20% in weever fish, scallop and shrimp samples spiked at a lower level of 13-31pgg(-1)ww and a higher level of 50-125pgg(-1)ww. Certified reference materials were analyzed with acceptable results. The method reduced solvent consumption, analytical time and labor, and is suitable for the routine analysis of PBDEs and PCBs in fishery and aquaculture products. PMID:24321764

  9. Assessment of two-phase olive mill solid waste and microalgae co-digestion to improve methane production and process kinetics.

    PubMed

    Fernández-Rodríguez, M J; Rincón, B; Fermoso, F G; Jiménez, A M; Borja, R

    2014-04-01

    Olive mill solid waste (OMSW) is a pollutant waste coming from olive oil elaboration by the two-phase centrifugation system. OMSW has a high organic matter content and unbalanced carbon to nitrogen (C/N) ratio, 31/1, which avoids obtaining high methane yields in the anaerobic digestion of this waste. In the present study a microalgae, Dunaliella salina, was employed as co-substrate for the OMSW anaerobic digestion in order to decrease the C/N ratio and increase its biodegradability. Different co-digestion mixtures (C/N ratios) were studied. The increase of D. salina from 25% to 50% in the co-digestion mixture clearly increased the biodegradability of the sole substrates. The highest biodegradability was found for the co-digestion mixture 50% OMSW-50% D. salina. Nevertheless, the maximum methane production, 330mLCH4/gVSadded, and the highest methane production rate were obtained for the co-digestion mixture 75% OMSW-25% D. salina, keeping a C/N ratio near to 26.7/1. PMID:24561632

  10. Phases and Phase Transitions

    NASA Astrophysics Data System (ADS)

    Gitterman, Moshe

    2014-09-01

    In discussing phase transitions, the first thing that we have to do is to define a phase. This is a concept from thermodynamics and statistical mechanics, where a phase is defined as a homogeneous system. As a simple example, let us consider instant coffee. This consists of coffee powder dissolved in water, and after stirring it we have a homogeneous mixture, i.e., a single phase. If we add to a cup of coffee a spoonful of sugar and stir it well, we still have a single phase -- sweet coffee. However, if we add ten spoonfuls of sugar, then the contents of the cup will no longer be homogeneous, but rather a mixture of two homogeneous systems or phases, sweet liquid coffee on top and coffee-flavored wet sugar at the bottom...

  11. Quantification of flavan-3-ols and phenolic acids in milk-based food products by reversed-phase liquid chromatography-tandem mass spectrometry.

    PubMed

    Redeuil, Karine; Bertholet, Raymond; Kussmann, Martin; Steiling, Heike; Rezzi, Serge; Nagy, Kornél

    2009-11-20

    This article reports the development and validation of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the comprehensive quantification of flavan-3-ol and phenolic acid constituents of milk-based food products. Isotope dilution-based sample preparation consisted of protein precipitation using acidic methanol enriched with the stable isotope labelled internal standards and ultrafiltration to preserve overall polyphenol composition, but to eliminate milk proteins in order to comply with LC. Reversed-phase liquid chromatography was optimized to achieve separation of 22 analytes in 8 min in order to reduce suppression effects, achieve a wide dynamic range and, most importantly, to resolve isomeric compounds. Negative-ion electrospray mass spectrometric detection and fragmentation of analytes was optimized, final transitions were selected for maximized selectivity, reliable quantification and reduction of false positives. The quantitative performance of the method was validated, the main features include: (1) range of lower limits of detection 5-15 ng/mL for flavan-3-ols, 60-100 ng/mL for procyanidins, 1-60 ng/mL for other phenolic acids, (2) lower limits of quantification 15-45 ng/mL for flavan-3-ols, 200-300 ng/mL for procyanidins, 3-200 ng/mL for other phenolic acids, (3) averaged intra-day precision 9.5%, (4) calibrated range 60-300,000 ng/mL for flavan-3-ols, 900-900,000 ng/mL for procyanidins, 9-225,000 ng/mL for other phenolic acids, (5) averaged accuracy 99.5%. Applications for yoghurt and ice-cream products are given. The presented data suggest that this method will help to better characterize the polyphenol composition of milk-based food products for quality control, assessment of dietary intake and for polyphenol bioavailability/bioefficacy studies. PMID:19833343

  12. Development of a multianalyte method based on micro-matrix-solid-phase dispersion for the analysis of fragrance allergens and preservatives in personal care products.

    PubMed

    Celeiro, Maria; Guerra, Eugenia; Lamas, J Pablo; Lores, Marta; Garcia-Jares, Carmen; Llompart, Maria

    2014-05-30

    An effective, simple and low cost sample preparation method based on matrix solid-phase dispersion (MSPD) followed by gas chromatography-mass spectrometry (GC-MS) or gas chromatography-triple quadrupole-mass spectrometry (GC-MS/MS) has been developed for the rapid simultaneous determination of 38 cosmetic ingredients, 25 fragrance allergens and 13 preservatives. All target substances are frequently used in cosmetics and personal care products and they are subjected to use restrictions or labeling requirements according to the EU Cosmetic Directive. The extraction procedure was optimized on real non-spiked rinse-off and leave-on cosmetic products by means of experimental designs. The final miniaturized process required the use of only 0.1g of sample and 1 mL of organic solvent, obtaining a final extract ready for analysis. The micro-MSPD method was validated showing satisfactory performance by GC-MS and GC-MS/MS analysis. The use of GC coupled to triple quadrupole mass detection allowed to reach very low detection limits (low ng g(-1)) improving, at the same time, method selectivity. In an attempt to improve the chromatographic analysis of preservatives, the inclusion of a derivatization step was also assessed. The proposed method was applied to a broad range of cosmetics and personal care products (shampoos, body milk, moisturizing milk, toothpaste, hand creams, gloss lipstick, sunblock, deodorants and liquid soaps among others), demonstrating the extended use of these substances. The concentration levels were ranging from the sub parts per million to the parts per mill. The number of target fragrance allergens per samples was quite high (up to 16). Several fragrances (linalool, farnesol, hexylcinnamal, and benzyl benzoate) have been detected at levels >0.1% (1,000 μg g(-1)). As regards preservatives, phenoxyethanol was the most frequently found additive reaching quite high concentration (>1,500 μg g(-1)) in five cosmetic products. BHT was detected in eight

  13. Development of a Hydrogasification Process for Co-Production of Substitute Natural Gas (SNG) and Electric Power from Western Coals-Phase I

    SciTech Connect

    Raymond Hobbs

    2007-05-31

    The Advanced Hydrogasification Process (AHP)--conversion of coal to methane--is being developed through NETL with a DOE Grant and has successfully completed its first phase of development. The results so far are encouraging and have led to commitment by DOE/NETL to begin a second phase--bench scale reactor vessel testing, expanded engineering analysis and economic perspective review. During the next decade new means of generating electricity, and other forms of energy, will be introduced. The members of the AHP Team envision a need for expanded sources of natural gas or substitutes for natural gas, to fuel power generating plants. The initial work the team has completed on a process to use hydrogen to convert coal to methane (pipeline ready gas) shows promising potential. The Team has intentionally slanted its efforts toward the needs of US electric utilities, particularly on fuels that can be used near urban centers where the greatest need for new electric generation is found. The process, as it has evolved, would produce methane from coal by adding hydrogen. The process appears to be efficient using western coals for conversion to a highly sought after fuel with significantly reduced CO{sub 2} emissions. Utilities have a natural interest in the preservation of their industry, which will require a dramatic reduction in stack emissions and an increase in sustainable technologies. Utilities tend to rank long-term stable supplies of fuel higher than most industries and are willing to trade some ratio of cost for stability. The need for sustainability, stability and environmentally compatible production are key drivers in the formation and progression of the AHP development. In Phase II, the team will add a focus on water conservation to determine how the basic gasification process can be best integrated with all the plant components to minimize water consumption during SNG production. The process allows for several CO{sub 2} reduction options including consumption of

  14. Properties of the adenovirus IVa2 gene product, an effector of late-phase-dependent activation of the major late promoter.

    PubMed Central

    Lutz, P; Kedinger, C

    1996-01-01

    The adenovirus major late promoter is strongly activated after the onset of viral DNA replication. Sequence elements located downstream of the major later promoter start site have previously been shown to be essential for this activation. Two proteins (DEF-A and DEF-B) bind to these elements in a late-phase-dependent manner. DEF-B has been identified as the product of adenovirus intermediate gene IVa2 (pIVa2) (C. Tribouley, P. Lutz, A. Staub, and C. Kedinger, J. Virol. 68:4450-4457, 1994). Here we show that pIVa2, while monomeric in solution, binds to its recognition sequence as a dimer and that two 20-residue amphipathic alpha helices play an essential role in this DNA-binding activity. Attempts to purify DEF-A have failed, but its chromatographic behavior, together with its immunological properties, established that pIVa2 is also a component of this heteromeric protein. In addition, the time course of pIVa2 synthesis during infection correlated with simultaneous detection of the binding of both DEF-A and DEF-B complexes to the downstream elements. Finally, as revealed by immunomicroscopy, pIVa2 is targeted to the nucleus, where it distributes to restricted locations in the nucleoplasm, as well as to the nucleoli. Altogether, these results demonstrate that pIVa2 plays a critical role in the transition from the early to the late phase of the lytic cycle. Furthermore, pIVa2 may serve additional functions yet to be uncovered, as suggested by its presence within the cell nucleolus. PMID:8627656

  15. Determination of the four major surfactant classes in cleaning products by reversed-phase liquid chromatography using serially connected UV and evaporative light-scattering detection.

    PubMed

    Escrig-Doménech, Aarón; Simó-Alfonso, Ernesto F; Ramis-Ramos, Guillermo

    2016-08-17

    A method for the simultaneous determination of the most frequently used surfactant families -linear alkyl benzenesulphonates (LAS), alkyl ether sulphates (AES), fatty alcohol ethoxylates (FAE) and oleins (soaps, fatty acid salts) - in cleaning products, has been developed. The common reversed phase octyl (C8), pentafluorophenyl and biphenyl columns were not capable of separating the anionic LAS and AES classes; however, since only LAS absorbs in the UV, these two classes were independently quantified using a C8 column and serially connected UV and ELSD detection. The best compromise to resolve the four surfactant classes and the oligomers within the classes was achieved with a C8 column and an ACN/water gradient. To enhance retention of the anionic surfactants, ammonium acetate, as an ion-pairing agent compatible with ELSD detection, was used. Also, to shift the olein peaks with respect to that of the FAE oligomers, acetic acid was used. In the optimized method, modulation of the mobile phase, using ammonium acetate during elution of LAS and AES, and acetic acid after elution of LAS and AES, was provided. Quantitation of the overlapped LAS and AES classes was achieved by using the UV detector to quantitate LAS and the ELSD to determine AES by difference. Accuracy in the determination of AES was achieved by using a quadratic model, and by correcting the predicted AES concentration according to the LAS concentration previously established using the UV chromatogram. Another approach also leading to accurate predictions of the AES concentration was to increase the AES concentrations in the samples by adding a standard solution. In the samples reinforced with AES, correction of the predicted AES concentration was not required. FAE and olein were quantified using also quadratic calibration. PMID:27286775

  16. MicroRNAs as master regulators of the plant NB-LRR defense gene family via the production of phased, trans-acting siRNAs.

    PubMed

    Zhai, Jixian; Jeong, Dong-Hoon; De Paoli, Emanuele; Park, Sunhee; Rosen, Benjamin D; Li, Yupeng; González, Alvaro J; Yan, Zhe; Kitto, Sherry L; Grusak, Michael A; Jackson, Scott A; Stacey, Gary; Cook, Douglas R; Green, Pamela J; Sherrier, D Janine; Meyers, Blake C

    2011-12-01

    Legumes and many nonleguminous plants enter symbiotic interactions with microbes, and it is poorly understood how host plants respond to promote beneficial, symbiotic microbial interactions while suppressing those that are deleterious or pathogenic. Trans-acting siRNAs (tasiRNAs) negatively regulate target transcripts and are characterized by siRNAs spaced in 21-nucleotide (nt) "phased" intervals, a pattern formed by DICER-LIKE 4 (DCL4) processing. A search for phased siRNAs (phasiRNAs) found at least 114 Medicago loci, the majority of which were defense-related NB-LRR-encoding genes. We identified three highly abundant 22-nt microRNA (miRNA) families that target conserved domains in these NB-LRRs and trigger the production of trans-acting siRNAs. High levels of small RNAs were matched to >60% of all ∼540 encoded Medicago NB-LRRs; in the potato, a model for mycorrhizal interactions, phasiRNAs were also produced from NB-LRRs. DCL2 and SGS3 transcripts were also cleaved by these 22-nt miRNAs, generating phasiRNAs, suggesting synchronization between silencing and pathogen defense pathways. In addition, a new example of apparent "two-hit" phasiRNA processing was identified. Our data reveal complex tasiRNA-based regulation of NB-LRRs that potentially evolved to facilitate symbiotic interactions and demonstrate miRNAs as master regulators of a large gene family via the targeting of highly conserved, protein-coding motifs, a new paradigm for miRNA function. PMID:22156213

  17. Measurements of acetone and other gas phase product yields from the OH-initiated oxidation of terpenes by proton-transfer-reaction mass spectrometry (PTR-MS)

    NASA Astrophysics Data System (ADS)

    Wisthaler, A.; Jensen, N. R.; Winterhalter, R.; Lindinger, W.; Hjorth, J.

    The atmospheric oxidation of several terpenes appears to be a potentially relevant source of acetone in the atmosphere. Proton-transfer-reaction mass spectrometry was used as an on-line analytical method in a chamber study to measure acetone and other gas phase products from the oxidation of α- and β-pinene initiated by OH radicals in air and in the presence of NO x. Acetone may be formed promptly, following attack by the OH radical on the terpene, via a series of highly unstable radical intermediates. It can also be formed by slower processes, via degradation of stable non-radical intermediates such as pinonaldehyde and nopinone. Primary acetone and pinonaldehyde molar yields of 11±2% (one σ) and 34±9% (one σ), respectively, were found from the reaction between α-pinene and the OH radical. After all α-pinene had been consumed, an additional formation of acetone due to the degradation of stable non-radical intermediates was observed. The total amount of acetone formed was 15±2% (one σ) of the reacted α-pinene. An upper limit of 12±3% (one σ) for the acetone molar yield from the oxidation of pinonaldehyde was established. From the reaction between β-pinene and the OH radicals, primary acetone and nopinone molar yields of 13±2% (one σ) and 25±3% (one σ), respectively, were observed. Additional amounts of acetone were formed by the further degradation of the primary product, such as the most abundant product nopinone. The total amount of acetone formed was 16±2% (one σ) of the reacted β-pinene. An upper limit of 12±2% (one σ) for the acetone molar yield from the oxidation of nopinone was established. The observed product yields from α- and β-pinene are in good agreement with other studies using mass-spectrometric and gas chromatographic analytical techniques, but differ significantly from previous studies using spectroscopic methods. Possible reasons for the discrepancies are discussed.

  18. Effects of volatiles on phase equilibria of a basalt from Piton de la Fournaise (Réunion island): experimental results and comparison with natural products.

    NASA Astrophysics Data System (ADS)

    Brugier, Yann-Aurélien; Pichavant, Michel; di Muro, Andréa; Bourdier, Jean-Louis

    2015-04-01

    The eruptive activity of the Piton de la Fournaise (PdF) hotspot volcano is monitored by geophysical, geochemical and petrological approaches. Nevertheless, the structure of the feeding system and magma reservoirs is still debated. 4 different lava groups occur at PdF: (1) Steady State Basalts (SSB), the dominant group in the recent activity, (2) the Differentiated Lavas group, typical of the early activity, (3) the Picrites group with olivine-rich lavas (oceanites) characteristic of La Réunion volcanism and (4) the Abnormal Group (AbG) that contains lavas with mixed geochemical characteristics. To understand the petrogenetic relations between the 4 groups of lavas, constrain the structure of the feeding system and the magma storage conditions, experimental phase equilibria have been determined under fluid-present conditions, with either H2O or H2O+CO2 added, for a SSB lava from the 2009 eruption. Experiments have been performed both at high pressures (HP) and 1atm. The HP experiments were carried out in an IHPV, pressurized with Ar-H2 mixtures, at 50MPa and 400MPa. The 1atm experiments used a vertical CO-CO2 gas mixing furnace. Experimental products were analyzed by SEM, EMPA and µ-FTIR Spectroscopy. Results at 50 MPa lead to a crystallization sequence in the order olivine (ol, + spinel), clinopyroxene (cpx), plagioclase (plag). Volatile concentrations in experimental glasses range from 0.5 to 1 wt% for H2O and 30 to 180 ppm for CO2, within the range of glass inclusions in olivine phenocrysts. Fo contents in ol, Mg# in cpx and An contents in plag are in agreement with compositions of natural phenocrysts, suggesting that our experiments closely approach the shallow magmatic evolution at PdF. Preliminary experiments at 400 MPa indicate a change in the crystallization sequence, olivine being replaced by cpx as the liquidus phase. Our data are in marked contrast with previous experimental results under volatile-free conditions. Experiments at 1 atm are in progress

  19. Constructing the 'Best' Reliability Data for the Job - Developing Generic Reliability Data from Alternative Sources Early in a Product's Development Phase

    NASA Technical Reports Server (NTRS)

    Kleinhammer, Roger K.; Graber, Robert R.; DeMott, D. L.

    2016-01-01

    Reliability practitioners advocate getting reliability involved early in a product development process. However, when assigned to estimate or assess the (potential) reliability of a product or system early in the design and development phase, they are faced with lack of reasonable models or methods for useful reliability estimation. Developing specific data is costly and time consuming. Instead, analysts rely on available data to assess reliability. Finding data relevant to the specific use and environment for any project is difficult, if not impossible. Instead, analysts attempt to develop the "best" or composite analog data to support the assessments. Industries, consortia and vendors across many areas have spent decades collecting, analyzing and tabulating fielded item and component reliability performance in terms of observed failures and operational use. This data resource provides a huge compendium of information for potential use, but can also be compartmented by industry, difficult to find out about, access, or manipulate. One method used incorporates processes for reviewing these existing data sources and identifying the available information based on similar equipment, then using that generic data to derive an analog composite. Dissimilarities in equipment descriptions, environment of intended use, quality and even failure modes impact the "best" data incorporated in an analog composite. Once developed, this composite analog data provides a "better" representation of the reliability of the equipment or component. It can be used to support early risk or reliability trade studies, or analytical models to establish the predicted reliability data points. It also establishes a baseline prior that may updated based on test data or observed operational constraints and failures, i.e., using Bayesian techniques. This tutorial presents a descriptive compilation of historical data sources across numerous industries and disciplines, along with examples of contents

  20. Demonstration of in situ product recovery of butyric acid via CO2 -facilitated pH swings and medium development in two-phase partitioning bioreactors.

    PubMed

    Peterson, Eric C; Daugulis, Andrew J

    2014-03-01

    Production of organic acids in solid-liquid two-phase partitioning bioreactors (TPPBs) is challenging, and highly pH-dependent, as cell growth occurs near neutral pH, while acid sorption occurs only at low pH conditions. CO2 sparging was used to achieve acidic pH swings, facilitating undissociated organic acid uptake without generating osmotic stress inherent in traditional acid/base pH control. A modified cultivation medium was formulated to permit greater pH reduction by CO2 sparging (pH 4.8) compared to typical media (pH 5.3), while still possessing adequate nutrients for extensive cell growth. In situ product recovery (ISPR) of butyric acid (pKa = 4.8) produced by Clostridium tyrobutyricum was achieved through intermittent CO2 sparging while recycling reactor contents through a column packed with absorptive polymer Hytrel® 3078. This polymer was selected on the basis of its composition as a polyether copolymer, and the use of solubility parameters for predicting solute polymer affinity, and was found to have a partition coefficient for butyric acid of 3. Total polymeric extraction of 3.2 g butyric acid with no CO2 mediated pH swings was increased to 4.5 g via CO2 -facilitated pH shifting, despite the buffering capacity of butyric acid, which resists pH shifting. This work shows that CO2 -mediated pH swings have an observable positive effect on organic acid extraction, with improvements well over 150% under optimal conditions in early stage fermentation compared to CO2 -free controls, and this technique can be applied other organic acid fermentations to achieve or improve ISPR. PMID:23996152

  1. Production of high specific activity (195m) Pt-cisplatinum at South African Nuclear Energy Corporation for Phase 0 clinical trials in healthy individual subjects.

    PubMed

    Zeevaart, Jan Rijn; Wagener, Judith; Marjanovic-Painter, Biljana; Sathekge, Mike; Soni, Nischal; Zinn, Christa; Perkins, Gary; Smith, Suzanne V

    2013-01-01

    Platinum agents continue to be the main chemotherapeutic agents used in the first-line and second-line treatments of cancer patients. It is important to fully understand the biological profile of these compounds in order to optimize the dose given to each patient. In a joint project with the Australian Nuclear Science and Technology Organisation and the Nuclear Medicine Department at Steve Biko Academic Hospital, South African Nuclear Energy Corporation synthesized and supplied (195m) Pt-cisplatinum (commonly referred to as cisplatin) for a clinical pilot study on healthy volunteers. Enriched (194) PtCl2 was prepared by digestion of enriched (194) Pt metal (>95%) followed by thermal decomposition over a 3 h period. The (194) PtCl2 was then placed in a quartz ampoule, was irradiated in SAFARI-1 up to 200 h, then decay cooled for a minimum of 34 h prior to synthesis of final product. (195m) Pt(NH3 )2 I2 , formed with the addition of KI and NH4 OH, was converted to the diaqua species [(195m) Pt(NH3 )2 (H2 O)2 ](2+) by reaction with AgNO3 . The conversion to (195m) Pt-cisplatinum was completed by the addition of concentrated HCl. The final product yield was 51.7% ± 5.2% (n = 5). The chemical and radionuclidic purity in each case was >95%. The use of a high flux reactor position affords a higher specific activity product (15.9 ± 2.5 MBq/mg at end of synthesis) than previously found (5 MBq/mg). Volunteers received between 108 and 126 MBq of radioactivity, which is equivalent to 6.8-10.0 mg of carrier cisplatinum. Such high specific activities afforded a significant reduction (~50%) in the chemical dose of a carrier cisplatinum, which represents less than 10% of a typical chemotherapeutic dose given to patients. A good manufacturing practice GMP compliant product was produced and was administered to 10 healthy volunteers as part of an ethically approved Phase 0 clinical trial. The majority of the injected activity 27.5% ± 5.8% was excreted

  2. Application of magnetic solid phase extraction for separation and determination of aflatoxins B ₁ and B₂ in cereal products by high performance liquid chromatography-fluorescence detection.

    PubMed

    Hashemi, Mahdi; Taherimaslak, Zohreh; Rashidi, Somayeh

    2014-06-01

    A simple and sensitive method based on the magnetic solid phase extraction with modified magnetic nanoparticles followed by high performance liquid chromatography with fluorescence detection has been developed for extraction and determination of aflatoxins B1 (AFB1) and B2 (AFB2) in cereal products. Magnetic nanoparticle coated with 3-(trimethoxysilyl)-1-propanthiol (TMSPT) and modified with 2-amino-5-mercapto-1,3,4-thiadiazole (AMT) was used as an antibody-free adsorbent. Under the optimal conditions, the calibration curves for AFB1 and AFB2 were linear in the ranges of 0.2-15 μg L(-1) and 0.04-3 μg L(-1), respectively. Detection limit was 0.041 μg L(-1) for AFB1 and 0.013 μg L(-1) for AFB2. The proposed method was successfully applied to the determination of AFB1 and AFB2 in spiked corn and rice samples with an average recovery of 93.5%. The results demonstrated that the developed method is simple, rapid, inexpensive, accurate and remarkably free from interference effects. PMID:24814005

  3. PCDDs, PCDFs and PCNs in products of microwave-assisted pyrolysis of woody biomass--Distribution among solid, liquid and gaseous phases and effects of material composition.

    PubMed

    Gao, Qiuju; Budarin, Vitaliy L; Cieplik, Mariusz; Gronnow, Mark; Jansson, Stina

    2016-02-01

    Microwave-assisted pyrolysis (MAP) of lignocellulosic biomass is a technique that could potentially be used to produce and upgrade renewable energy carriers. However, there is no available information about the formation of dioxins and other organic pollutants in MAP treatment of woody biomass. In this study, MAP experiments were conducted in lab-scale using virgin softwood, bark, and impregnated wood as feedstocks. The non-condensable gas, liquid (fractionated into aqueous and oil phases), and char fractions generated during pyrolysis were collected and analysed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and naphthalenes (PCNs). The concentrations of PCDDs, PCDFs and PCNs in the pyrolysis products ranged from 0.52 to 43.7 ng kg(-1). All investigated compound groups were most abundant in the oil fraction, accounting for up to 68% (w/w) of the total concentrations. The highest PCDD, PCDF and PCN concentrations were found from the pyrolysis of bark, which has relatively high contents of chlorine and mineral matter, followed by impregnated wood, which contains organic and metal-based preservatives. The homologue profiles of all three compound groups were dominated by the less chlorinated homologues. The homologue abundance decreased as the degree of chlorination increased. This trend was observed for all three feedstocks. PMID:26688256

  4. Determination of nine volatile N-nitrosamines in tobacco and smokeless tobacco products by dispersive solid-phase extraction with gas chromatography and tandem mass spectrometry.

    PubMed

    Lv, Fang; Guo, Junwei; Yu, Fei; Zhang, Tingting; Zhang, Shimin; Cui, Huapeng; Liu, Xianjun; Chen, Li; Liu, Leiyu; Liu, Shaofeng; Xie, Fuwei

    2016-06-01

    A method was developed for the determination of nine volatile N-nitrosamines in tobacco and smokeless tobacco products. The targets are N-nitrosodimethylamine, N-nitrosopyrrolidine, N-nitrosopiperidine, N-nitrosomorpholine, N-nitrosoethylmethylamine, N-nitrosodiethylamine, N-nitrosodipropylamine, N-nitrosobuylmethylmine, and N-nitrosodibutylamine. The samples were treated by dispersive solid-phase extraction using 1 g of primary secondary amine and 0.5 g of carbon and then analyzed by gas chromatography with tandem mass spectrometry with an electron impact ion source. The recoveries for the targets ranged from 84 to 118%, with <16% relative standard deviations at three spiking levels of 0.5, 1.25, and 2.5 ng/g. The limits of detection ranged from 0.03 to 0.15 ng/g. With the use of the proposed method, we detected the presence of six nitrosamines in the range of 0.4-30.7 ng/g. The study demonstrated that the method could be used as a rapid, convenient, and high-throughput method for N-nitrosamines analysis in tobacco matrix. PMID:27059265

  5. Improvement of Nicotinic Acid and Nicotinamide Analysis in Meats and Meat Products by HPLC and LC-MS/MS with Solid-Phase Extraction.

    PubMed

    Hiki, Asako; Yamajima, Yukiko; Uematsu, Yoko

    2016-01-01

    A method for nicotinic acid (NA) and nicotinamide (NAA) analysis in meats was developed. NA and NAA were extracted from meats or meat products with metaphosphate aqueous solution. The extract was cleaned up with an Oasis MCX cartridge. The cartridge was washed with 2% acetic acid (v/v) and acetic acid-methanol solution. NA and NAA were eluted with ammonia-methanol solution. NA and NAA in the eluate were chromatographed on a Scherzo SM-C18 (3.0×150 mm, 3.0 μm) column with 20 mmol/L ammonium acetate containing 0.1% acetic acid-acetonitrile (97 : 3) as a mobile phase and were monitored at 261 nm. Quantification was performed by LC and LC-MS/MS. Calibration curves showed high linearity (correlation coefficient>0.998) between 1-25 μg/mL for LC and LC-MS/MS. Recoveries were 84-108% (CV≦5.8%) by HPLC and 79-105% (CV≦9.0%) by LC-MS/MS. The limit of quantitation for NA was 0.005-0.01 g/kg and that for NAA was 0.01-0.02 g/kg. PMID:27558227

  6. Application of a β-cyclodextrin/graphene oxide-modified fiber for solid-phase microextraction of six fragrance allergens in personal products.

    PubMed

    Hou, Xiudan; Wang, Licheng; Tang, Xiaofen; Xiong, Chunming; Guo, Yong; Liu, Xia

    2015-10-01

    A new β-cyclodextrin/graphene oxide hybrid material prepared via a chemical covalent interaction and layer-to-layer assembly was developed as a sorbent for the solid-phase microextraction of fragrance allergens. As a result of its ultra-large surface area, large delocalized π-electron system and abundant hydroxyls, the β-cyclodextrin/graphene oxide-coated fiber could be used to extract particular compounds via strong π-π interactions, van der Waals forces and hydrogen bonding interactions. β-Cyclodextrin with a hydrophobic interior cavity and hydrophilic peripheral face was conducive in extracting the fragrances with hydrophobic and hydrophilic groups. Under the optimized extraction and desorption conditions, the β-cyclodextrin/graphene oxide-coated fiber showed acceptable extraction efficiency for hydrophilic and hydrogen-bonding-donating alcohols. Compared with other methods based on different coating fibers, the proposed fiber obtained wide linear ranges for fragrances with correlation coefficients ranging from 0.9921 to 0.9970, and low limits of detection in the range of 0.050-0.150 μg L(-1). The obtained results indicated that the newly developed fiber was a selective, feasible and cost-effective microextraction medium and could be successfully applied for the determination of several fragrances in personal products. PMID:26332186

  7. On-line solid phase extraction-liquid chromatography-mass spectrometry for trace determination of nerve agent degradation products in water samples.

    PubMed

    Røen, Bent T; Sellevåg, Stig R; Lundanes, Elsa

    2013-01-25

    Three primary nerve agent degradation products (ethyl-, isopropyl- and pinacolyl methylphosphonic acid) have been determined in water samples using on-line solid phase extraction-liquid chromatography and mass spectrometry (SPE-LC-MS) with electrospray ionisation. Porous graphitic carbon was employed for analyte enrichment followed by hydrophilic interaction chromatography. Diethylphosphate was applied as internal standard for quantitative determination of the alkyl methylphosphonic acids (AMPAs). By treating the samples with strong cation-exhange columns on Ba, Ag and H form, the major inorganic anions in water were removed by precipitation prior to the SPE-LC-MS determination. The AMPAs could be determined in tap water with limits of detection of 0.01-0.07 μg L(-1) with the [M-H](-) ions extracted at an accuracy of ±5 mDa. The within and between assay precisions at analyte concentrations of 5 μg L(-1) were 2-3%, and 5-9% relative standard deviation, respectively. The developed method was employed for determination of the AMPAs in three natural waters and a simulated waste water sample, spiked at 5 μg L(-1). Recoveries of ethyl-, isopropyl- and pinacolyl methylphosphonic acid were 80-91%, 92-103% and 99-106%, respectively, proving the applicability of the technique for natural waters of various origins. PMID:23312321

  8. Simulating the production and dispersion of environmental pollutants in aerosol phase in an urban area of great historical and cultural value.

    PubMed

    Librando, Vito; Tringali, Giuseppe; Calastrini, Francesca; Gualtieri, Giovanni

    2009-11-01

    Mathematical models were developed to simulate the production and dispersion of aerosol phase atmospheric pollutants which are the main cause of the deterioration of monuments of great historical and cultural value. This work focuses on Particulate Matter (PM) considered the primary cause of monument darkening. Road traffic is the greatest contributor to PM in urban areas. Specific emission and dispersion models were used to study typical urban configurations. The area selected for this study was the city of Florence, a suitable test bench considering the magnitude of architectural heritage together with the remarkable effect of the PM pollution from road traffic. The COPERT model, to calculate emissions, and the street canyon model coupled with the CALINE model, to simulate pollutant dispersion, were used. The PM concentrations estimated by the models were compared to actual PM concentration measurements, as well as related to the trend of some meteorological variables. The results obtained may be defined as very encouraging even the models correlated poorly: the estimated concentration trends as daily averages moderately reproduce the same trends of the measured values. PMID:18974943

  9. RECQ5 helicase associates with the C-terminal repeat domain of RNA polymerase II during productive elongation phase of transcription

    PubMed Central

    Kanagaraj, Radhakrishnan; Huehn, Daniela; MacKellar, April; Menigatti, Mirco; Zheng, Lu; Urban, Vaclav; Shevelev, Igor; Greenleaf, Arno L.; Janscak, Pavel

    2010-01-01

    It is known that transcription can induce DNA recombination, thus compromising genomic stability. RECQ5 DNA helicase promotes genomic stability by regulating homologous recombination. Recent studies have shown that RECQ5 forms a stable complex with RNA polymerase II (RNAPII) in human cells, but the cellular role of this association is not understood. Here, we provide evidence that RECQ5 specifically binds to the Ser2,5-phosphorylated C-terminal repeat domain (CTD) of the largest subunit of RNAPII, RPB1, by means of a Set2–Rpb1-interacting (SRI) motif located at the C-terminus of RECQ5. We also show that RECQ5 associates with RNAPII-transcribed genes in a manner dependent on the SRI motif. Notably, RECQ5 density on transcribed genes correlates with the density of Ser2-CTD phosphorylation, which is associated with the productive elongation phase of transcription. Furthermore, we show that RECQ5 negatively affects cell viability upon inhibition of spliceosome assembly, which can lead to the formation of mutagenic R-loop structures. These data indicate that RECQ5 binds to the elongating RNAPII complex and support the idea that RECQ5 plays a role in the maintenance of genomic stability during transcription. PMID:20705653

  10. Multiresidue trace analysis of pharmaceuticals, their human metabolites and transformation products by fully automated on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry.

    PubMed

    García-Galán, María Jesús; Petrovic, Mira; Rodríguez-Mozaz, Sara; Barceló, Damià

    2016-09-01

    A novel, fully automated analytical methodology based on dual column liquid chromatography coupled to tandem mass spectrometry (LC-LC-MS(2)) has been developed and validated for the analysis of 12 pharmaceuticals and 20 metabolites and transformation products in different types of water (influent and effluent wastewaters and surface water). Two LC columns were used - one for pre-concentration of the sample and the second for separation and analysis - so that water samples were injected directly in the chromatographic system. Besides the many advantages of the methodology, such as minimization of the sample volume required and its manipulation, both compounds ionized in positive and negative mode could be analyzed simultaneously without compromising the sensitivity. A comparative study of different mobile phases, gradients and LC pre-concentration columns was carried out to obtain the best analytical performance. Limits of detection (MLODs) achieved were in the low ngL(-1) range for all the compounds. The method was successfully applied to study the presence of the target analytes in different wastewater and surface water samples collected near the city of Girona (Catalonia, Spain). Data on the environmental presence and fate of pharmaceutical metabolites and TPs is still scarce, highlighting the relevance of the developed methodology. PMID:27343613

  11. Production development and utilization of Zimmer Station wet FGD by-products. Final report. Volume 6, Field study conducted in fulfillment of Phase 3 titled. Use of FGD by-product gypsum enriched with magnesium hydroxide as a soil amendment

    SciTech Connect

    Bigham, J. M.; Soto, U. I.; Stehouwer, R. C.; Yibirin, H.

    1999-04-30

    A variety of flue gas desulfurization (FGD) technologies have been developed to meet environmental restrictions imposed by the federal Clean Air Act and its amendments. These technologies include wet scrubber systems that dramatically reduce sulfur dioxide (SO2) emissions. Although such systems are effective, they also produce large volumes of sludge that must be dewatered, stabilized, and disposed of in landfills. Disposal is an expensive and environmentally questionable process for which suitable alternatives are needed. Wet scrubbing of flue gases with magnesium (Mg)-enhanced lime has the potential to become a leading FGD technology. When combined with aforced oxidation system, the wet sludges resulting from this process can be modified and refined to produce gypsum (CaS04∙2H2O) and magnesium hydroxide [Mg(OH)2] of sufficient purity for beneficial re-use in the construction (wallboard) and pharmaceutical industries. The pilot plant at the CINERGY Zimmer Station near Cincinnati can also produce gypsum by-products formulated to contain varying amounts of Mg(OH)2- Such materials may have value to the agriculture, forestry, and lawn-care industries as soil "conditioners", liming agents, and nutritional supplements capable of supplying calcium (Ca), Mg, and sulfur (S) for plant growth. This report describes three field studies designed to evaluate by-product gypsum and Mg-gypsum from the Zimmer Station power plant as amendments for improving the quality of mine spoils and agricultural soils that were unproductive because of phytotoxic levels of dissolved aluminum (Al) and low pH. The technical literature suggests that gypsum may be more effective than agricultural limestone for ameliorating Al toxicity below the immediate zone of application. Such considerations are important for deep-rooted plant species that attempt to utilize water and nutrients occurring at depth in the spoil/soil.

  12. Tandem anion and cation exchange solid phase extraction for the enrichment of micropollutants and their transformation products from ozonation in a wastewater treatment plant.

    PubMed

    Deeb, Ahmad A; Schmidt, Torsten C

    2016-06-01

    The presence of organic micropollutants and their transformation products (TPs) from biotic and abiotic processes in aquatic environments is receiving intense public and scientific attention. Yet a suitable sample preparation method that would enable extraction and enrichment of a wide range of such compounds from water is missing. The focus of this paper was to develop an enhanced solid phase extraction (SPE) protocol which enabled isolation of parent compounds and low molecular weight transformation products (that are produced after treatment of water with ozone) from different water matrices. Ten SPE sorbents were evaluated with regard to their ability to extract acidic, neutral, and basic compounds from water at several pH values. Highest recoveries (91-99 %) for all analytes in pure water were obtained by combining strong anion and cation exchangers of two manufacturers in a tandem mode without pH adjustment. Tandem Oasis (MAX+MCX) was finally applied to extract the spiked analytes from tap water, surface water, and several wastewater samples. The efficiency of the used SPE procedure was examined using an optimized liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method using multiple reaction monitoring (MRM) mode. The occurrence of some of the investigated TPs in environmental water matrices was proven for the first time in this study. Method quantification limits (MQLs) for all compounds ranged from 3.7 to 15.3 ng/L in all matrices. Recoveries (%RE) were between 90 and 110 %. Intraday and interday precision, expressed as relative standard deviation, varied from 0.7 to 5.9 % and 1.8 to 10.3 %, respectively. Matrix effect (%ME) evaluation demonstrated that even complex sample matrices did not show significant ion suppression or enhancement. The applicability of the method was shown during two sampling campaigns at Ruhr river and a wastewater treatment plant (WWTP) equipped with an ozonation step after regular

  13. Simultaneous direct analysis of benzimidazole fungicides and relevant metabolites in agricultural products based on multifunction dispersive solid-phase extraction and liquid chromatography-mass spectrometry.

    PubMed

    Guo, Bin; Huang, Zhiqiang; Wang, Meiling; Wang, Xiaoying; Zhang, Ying; Chen, Bo; Li, Yongjun; Yan, Hongfei; Yao, Shouzhuo

    2010-07-16

    A fast and flexible multi-residue procedure for effective extraction of benzimidazole fungicides and the related transformation products in various raw agricultural commodities is developed for direct and simultaneous analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The new sample preparation method, introduced to allow direct extraction of the labile fungicides as the intact forms in complex matrices, is achieved using a conservative homogenizing extraction and multifunction adsorption cleanup (CHEMAC), which basically involves salting-out partitioning/extraction with acetate-buffered acetonitrile at low-temperature and sequential rapid solid-phase dispersive cleanup with a ternary sorbent mixture. The CHEMAC procedure was optimized and further modified by incorporating several pretreatment variables influencing sample stability and process efficiency, such as pH, temperature, salt and sorbent utilized. By using CHEMAC, a noteworthy improvement in extraction recoveries was obtained for the problematic fungicides, while no significant differential matrix effects were detected on the LC-MS/MS analysis in all 9 matrices. The in-source fragmentation of benomyl occurred but caused no cross-talk interference in multi-component analysis. Thus the CHEMAC-based LC-MS/MS strategy can serve as an attractive approach to satisfactory overall process efficiencies (70-92%) with acceptable repeatability (relative standard deviations below 16%) for all the analyte-matrix combinations. Mean accuracies were obtained within the range of 70-110% at fortified levels of 1-500 ng/g, with intra-day and inter-day variations less than 15 and 20%, respectively. The successful practical application of the proposed method to real samples has also been demonstrated. PMID:20541210

  14. Simultaneous analysis of 45 pharmaceuticals and personal care products in sludge by matrix solid-phase dispersion and liquid chromatography tandem mass spectrometry.

    PubMed

    Li, Mingyue; Sun, Qian; Li, Yan; Lv, Min; Lin, Lifeng; Wu, Yang; Ashfaq, Muhammad; Yu, Chang-Ping

    2016-07-01

    Pharmaceuticals and personal care products (PPCPs) are a class of emerging contaminants widely distributed in the wastewater treatment system. The simultaneous analysis of multiple PPCPs in the sludge, which is a complex matrix, is still not fully studied. In this study, a procedure based on matrix solid-phase dispersion (MSPD) for the extraction of PPCPs from the sludge with determination by liquid chromatography tandem mass spectrometry (LC-MS/MS) was investigated. Forty-five PPCPs, including antibiotics, nonsteroidal anti-inflammatory drugs, β-blockers, antidepressants, antimicrobial agents, preservatives, UV filters, and so on, were studied. MSPD parameters, including the sorbent materials, the ratio of sample to sorbent, the eluent composition, and the elution volumes, were sequentially optimized. Best results were achieved by 0.1 g of sludge homogenized with 0.4 g of C18-bonded silica sorbent and elution by 6 mL methanol and 10 mL acetonitrile/5 % oxalic acid (8/2, v/v). The method quantification limits for the 45 PPCPs ranged 0.117-5.55 μg/kg. The PPCP recoveries ranged from 50.3 to 107 % with relative standard deviation lower than 15 %. The proposed method was applied to analyze PPCPs in the sludge collected from a domestic wastewater treatment plant over 1 year. Thirteen PPCPs were detected, with the concentrations of ofloxacin and triclocarban more than 1000 μg/kg. Temporal variations of the PPCP levels were observed. Thus, MSPD-LC-MS/MS method could achieve good sensitivity and recovery for the target PPCP analysis in the sludge samples, while MSPD provided one-step sample preparation which was easier and faster to perform compared to the commonly used methods. Graphical abstract Workflow of MSPD and LC-MS/MS chromatograms for PPCP analysis. PMID:27137519

  15. 30 CFR 203.43 - To which production do I apply the RSV earned from qualified deep wells or qualified phase 1...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... first qualified well that earns your lease the RSV begins production (other than test production). (2... well when production begins in August 2008. The first well earned an RSV of 25 BCF (see § 203.41(a)(1... second well had begun production in August 2009, it would not be a qualified deep well because it...

  16. 30 CFR 203.43 - To which production do I apply the RSV earned from qualified deep wells or qualified phase 1...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... production occurring on and after the later of: (i) May 3, 2004, for an RSV earned by a qualified deep well... interval the top of which is 16,600 feet TVD SS, which becomes a qualified deep well when production begins... production in August 2009, it would not be a qualified deep well because it started production...

  17. Catalysis for biomass and CO2 use through solar energy: opening new scenarios for a sustainable and low-carbon chemical production.

    PubMed

    Lanzafame, Paola; Centi, Gabriele; Perathoner, Siglinda

    2014-11-21

    The use of biomass, bio-waste and CO2 derived raw materials, the latter synthesized using H2 produced using renewable energy sources, opens new scenarios to develop a sustainable and low carbon chemical production, particularly in regions such as Europe lacking in other resources. This tutorial review discusses first this new scenario with the aim to point out, between the different possible options, those more relevant to enable this new future scenario for the chemical production, commenting in particular the different drivers (economic, technological and strategic, environmental and sustainability and socio-political) which guide the selection. The case of the use of non-fossil fuel based raw materials for the sustainable production of light olefins is discussed in more detail, but the production of other olefins and polyolefins, of drop-in intermediates and other platform molecules are also analysed. The final part discusses the role of catalysis in establishing this new scenario, summarizing the development of catalysts with respect to industrial targets, for (i) the production of light olefins by catalytic dehydration of ethanol and by CO2 conversion via FTO process, (ii) the catalytic synthesis of butadiene from ethanol, butanol and butanediols, and (iii) the catalytic synthesis of HMF and its conversion to 2,5-FDCA, adipic acid, caprolactam and 1,6-hexanediol. PMID:24577063

  18. Determination of Glyphosate, its Degradation Product Aminomethylphosphonic Acid, and Glufosinate, in Water by Isotope Dilution and Online Solid-Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry

    USGS Publications Warehouse

    Meyer, Michael T.; Loftin, Keith A.; Lee, Edward A.; Hinshaw, Gary H.; Dietze, Julie E.; Scribner, Elisabeth A.

    2009-01-01

    The U.S. Geological Survey method (0-2141-09) presented is approved for the determination of glyphosate, its degradation product aminomethylphosphonic acid (AMPA), and glufosinate in water. It was was validated to demonstrate the method detection levels (MDL), compare isotope dilution to standard addition, and evaluate method and compound stability. The original method USGS analytical method 0-2136-01 was developed using liquid chromatography/mass spectrometry and quantitation by standard addition. Lower method detection levels and increased specificity were achieved in the modified method, 0-2141-09, by using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The use of isotope dilution for glyphosate and AMPA and pseudo isotope dilution of glufosinate in place of standard addition was evaluated. Stable-isotope labeled AMPA and glyphosate were used as the isotope dilution standards. In addition, the stability of glyphosate and AMPA was studied in raw filtered and derivatized water samples. The stable-isotope labeled glyphosate and AMPA standards were added to each water sample and the samples then derivatized with 9-fluorenylmethylchloroformate. After derivatization, samples were concentrated using automated online solid-phase extraction (SPE) followed by elution in-line with the LC mobile phase; the compounds separated and then were analyzed by LC/MS/MS using electrospray ionization in negative-ion mode with multiple-reaction monitoring. The deprotonated derivatized parent molecule and two daughter-ion transition pairs were identified and optimized for glyphosate, AMPA, glufosinate, and the glyphosate and AMPA stable-isotope labeled internal standards. Quantitative comparison between standard addition and isotope dilution was conducted using 473 samples analyzed between April 2004 and June 2006. The mean percent difference and relative standard deviation between the two quantitation methods was 7.6 plus or minus 6.30 (n = 179), AMPA 9.6 plus or minus 8

  19. Cross-examination of liquid-liquid extraction (LLE) and solid-phase microextraction (SPME) methods for impurity profiling of methamphetamine.

    PubMed

    Lee, Jaesin; Park, Yonghoon; Yang, Wonkyung; Chung, Heesun; Choi, Wonjun; Inoue, Hiroyuki; Kuwayama, Kenji; Park, Jeonghill

    2012-02-10

    Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results. PMID:21376486

  20. Health-hazard evaluation report HETA 91-169-2196, Texprint Products, Macon, Georgia

    SciTech Connect

    Decker, J.A.; Shults, R.A.

    1992-03-01

    In response to a request from a union representative an evaluation was undertaken of possible hazardous working conditions at Texprint Products (SIC-2269), Macon, Georgia. Workers had complained of skin rashes and respiratory symptoms. The company was involved in the dyeing, printing and finishing of fabrics to be used for home furnishing and Japanese apparel. Exposures to formaldehyde (50000), caprolactam (105602), and mineral spirits were all well below established standards. Heat stress measurements were excessive. In one instance the core body temperature exceeded the recommended maximum of 38 degrees-C for one worker throughout the first shift. Eye irritation was reported by 25 (28%) of the workers with six (24%) reporting current or chronic rashes, seven (28%) reported headaches, and one (4%) reported more than one lower respiratory symptom. The authors conclude that a health hazard existed from excessive exposure to heat stress. Caustics and reactive dyes presented potential health hazards from dermal exposure. The authors recommend that a heat stress management program be implemented. The installation of engineering controls and the use of protective equipment by individual workers should be used to lessen the hazards of their jobs.

  1. Disruption of follistatin by RNAi increases apoptosis, arrests S-phase of cell cycle and decreases estradiol production in bovine granulosa cells.

    PubMed

    Chong, Zhenlu; Dong, Ping; Riaz, Hasan; Shi, Lei; Yu, Xue; Cheng, Ying; Yang, Liguo

    2015-04-01

    Follistatin (FST), a local regulator of gonadal functions is a powerful inhibitor of follicle stimulating hormone (FSH) secretion. In the present study, the expression of FST was partially silenced at both transcriptional and translational levels by RNAi-Ready pSIREN-RetroQ-ZsGreen Vector mediated recombinant pshRNA vectors in bovine granulosa cells (bGCs). The results showed that transfection with FST-1 and FST-2 vectors significantly down-regulated mRNA and protein expressions of follistatin by 51% (P = 0.0093) and 72% (P = 0.0078) respectively. After down-regulation of FST in bGCs, cell cycle was arrested at S-phase (9.2 ± 0.6 vs 12.5 ± 0.2, P = 0.0055), and apoptosis was significantly (21.3 ± 2.7 vs 13.9 ± 2.5, P = 0.0051) increased. These findings were further verified by down-regulation of protein level of B-cell leukemia/lymphoma 2 (Bcl2, P = 0.0423), and up-regulation of caspase-3 (P = 0.0362), p21 (P = 0.0067) and mRNA levels of Bcl2-associated X protein (Bax, P = 0.041). Knockdown of FST in bGCs significantly increased activin A concentration in culture medium, while level of estradiol (E2) was suppressed without affecting progesterone production. In addition, mRNA levels of all activin receptor subtypes [activin receptor types I (ACRI) and II (ACRIIA and ACRIIB)] and inhibin α-subunit were augmented (P < 0.05) without altering both inhibin β-subunits. These findings suggest that follistatin may participate in caspase3-dependent apoptosis through Bcl2/Bax gene family in bovine GCs, whereas, activin and its receptors are associated with its regulation. Activin-induced up-regulation of inhibin-α subunit in bGCs seems to be involved in the regulation of steroidogenesis. PMID:25728901

  2. 30 CFR 203.43 - To which production do I apply the RSV earned from qualified deep wells or qualified phase 1...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... qualified wells on or after May 3, 2004, reported on the OGOR-A for your lease under 30 CFR 1210.102, as and... first qualified well that earns your lease the RSV begins production (other than test production). (2... well when production begins in August 2008. The first well earned an RSV of 25 BCF (see §...

  3. 30 CFR 203.43 - To which production do I apply the RSV earned from qualified deep wells or qualified phase 1...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... qualified wells on or after May 3, 2004, reported on the OGOR-A for your lease under 30 CFR 1210.102, as and... first qualified well that earns your lease the RSV begins production (other than test production). (2... well when production begins in August 2008. The first well earned an RSV of 25 BCF (see §...

  4. EOSCUBE: A Constraint Database System for High-Level Specification and Efficient Generation of EOSDIS Products. Phase 1; Proof-of-Concept

    NASA Technical Reports Server (NTRS)

    Brodsky, Alexander; Segal, Victor E.

    1999-01-01

    The EOSCUBE constraint database system is designed to be a software productivity tool for high-level specification and efficient generation of EOSDIS and other scientific products. These products are typically derived from large volumes of multidimensional data which are collected via a range of scientific instruments.

  5. Revised Phase II Plan for the National Education Practice File Development Project Including: Creation; Pilot Testing; and Evaluation of a Test Practice File. Product 1.7/1.8 (Product 1.6 Appended).

    ERIC Educational Resources Information Center

    Benson, Gregory, Jr.; And Others

    A detailed work plan is presented for the conduct of Phase II activities, which are concerned with creating a pilot test file, conducting a test of it, evaluating the process and input of the file, and preparing the file management plan. Due to the outcomes of activities in Phase I, this plan was revised from an earlier outline. Included in the…

  6. PRODUCTION OF THE EXTREME-ULTRAVIOLET LATE PHASE OF AN X CLASS FLARE IN A THREE-STAGE MAGNETIC RECONNECTION PROCESS

    SciTech Connect

    Dai, Y.; Ding, M. D.; Guo, Y.

    2013-08-20

    We report on observations of an X class flare on 2011 September 6 by the instruments on board the Solar Dynamics Observatory. The flare occurs in a complex active region with multiple polarities. The Extreme-Ultraviolet (EUV) Variability Experiment observations in the warm coronal emission reveal three enhancements, the third of which corresponds to an EUV late phase. The three enhancements have a one-to-one correspondence to the three stages in flare evolution identified by the spatially resolved Atmospheric Imaging Assembly observations, which are characterized by a flux rope eruption, a moderate filament ejection, and the appearance of EUV late phase loops, respectively. The EUV late phase loops are spatially and morphologically distinct from the main flare loops. Multi-channel analysis suggests the presence of a continuous but fragmented energy injection during the EUV late phase resulting in the warm corona nature of the late phase loops. Based on these observational facts, we propose a three-stage magnetic reconnection scenario to explain the flare evolution. Reconnections in different stages involve different magnetic fields but show a casual relationship between them. The EUV late phase loops are mainly produced by the least energetic magnetic reconnection in the last stage.

  7. Effect of level of fiber of the rearing phase diets on egg production, digestive tract traits, and body measurements of brown egg-laying hens fed diets differing in energy concentration.

    PubMed

    Guzmán, P; Saldaña, B; Bouali, O; Cámara, L; Mateos, G G

    2016-08-01

    This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied. PMID:26976899

  8. Moon Phases

    ERIC Educational Resources Information Center

    Riddle, Bob

    2010-01-01

    When teaching Moon phases, the focus seems to be on the sequence of Moon phases and, in some grade levels, how Moon phases occur. Either focus can sometimes be a challenge, especially without the use of models and observations of the Moon. In this month's column, the author describes some of the lessons that he uses to teach the phases of the Moon…

  9. Liquid-liquid two phase systems for the production of porous hydrogels and hydrogel microspheres for biomedical applications: A tutorial review

    PubMed Central

    Elbert, Donald L.

    2010-01-01

    Macroporous hydrogels may have direct applications in regenerative medicine as scaffolds to support tissue formation. Hydrogel microspheres may be used as drug delivery vehicles or as building blocks to assemble modular scaffolds. A variety of techniques exist to produce macroporous hydrogels and hydrogel microspheres. A subset of these relies on liquid-liquid two phase systems. Within this subset, vastly different types of polymerization processes are found. In this review, the history, terminology and classification of liquid-liquid two phase polymerization and crosslinking are described. Instructive examples of hydrogel microsphere and macroporous scaffold formation by precipitation/dispersion, emulsion and suspension polymerizations are used to illustrate the nature of these processes. The role of the kinetics of phase separation in determining the morphology of scaffolds and microspheres is also delineated. Brief descriptions of miniemulsion, microemulsion polymerization and ionotropic gelation are also included. PMID:20659596

  10. Automated headspace solid-phase microextraction and on-fiber derivatization for the determination of clenbuterol in meat products by gas chromatography coupled to mass spectrometry.

    PubMed

    Jiang, Yong; Ni, Yongnian

    2015-02-01

    A method was developed for the determination of clenbuterol in meat using stable-isotope-dilution gas chromatography with mass spectrometry coupled with solid-phase microextraction and on-fiber derivatization. The samples were first homogenized with hydrochloric acid followed by protein deposition. After headspace solid-phase microextraction and on-fiber derivatization, the content of clenbuterol was measured with the aid of stable-isotope dilution. The condition of solid-phase microextraction was optimized by central composite design. The relative standard deviations, limit of detection, and recoveries for clenbuterol were 4.2-9.2%, 0.48 μg/kg, and 96-104%, respectively. The proposed method was satisfactory for analysis of real samples as compared with the Chinese standard method. PMID:25403577

  11. OZONATION BY-PRODUCTS 2. IMPROVEMENT OF AN AQUEOUS- PHASE DERIVITIZATION METHOD FOR THE DETECTION OF FORMALDEHYDE AND OTHER CARBONYL COMPOUNDS FORMED BY THE OZONATION OF DRINKING WATER

    EPA Science Inventory

    A method for the determination of low molecular weight aldehydes in water using aqueous-phase derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride has been improved by the use of high-resolution capillary GC. Detection limits with GC/ECD and GC/MS with ...

  12. IDENTIFYING SUITABLE INDICATORS FOR MEASURING SUSTAINABILITY OF BIOENERGY PRODUCTS DERIVED FROM PINE FORESTS IN THE U.S. SOUTH (PHASE-1)

    EPA Science Inventory

    In this phase of the project, a sustainability framework was developed for four sustainability indices namely: 1) economic; 2) biodiversity; 3) greenhouse gas emission reduction and net energy ratio; and 4) soil and water quali...

  13. 40 CFR 60.421 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... stream to the reactor/crystallizer for synthetic and coke oven by-product ammonium sulfate manufacturing...-product from process streams generated during caprolactam manufacture. Coke oven by-product...

  14. Production of VEGF receptor 1 and 2 mRNA and protein during endochondral bone repair is differential and healing phase specific

    PubMed Central

    Reumann, Marie K.; Nair, Turya; Strachna, Olga; Boskey, Adele L.

    2010-01-01

    Physiological disturbances, including temporary hypoxia, are expected to drive angiogenesis during bone repair. Evidence suggests that the angiogenic ligand vascular endothelial growth factor (VEGF)-A plays an important role in this process. We characterized the expression of two receptors that are essential for mediating VEGF signaling, VEGFR1/Flt-1 and VEGFR2/Flk-1/KDR, in a mouse rib fracture model. Their mRNA and protein levels were assessed in four healing phases, which were characterized histologically as hemorrhage formation on postfracture day (PFD) 1, inflammatory response on PFD 3, initiation of callus development on PFD 7, and the presence of a mature callus on PFD 14. Transcript was detected for VEGFR1 and VEGFR2, as well as VEGF. While mRNA expression of VEGFR1 was monophasic throughout all healing phases, VEGFR2 showed a biphasic profile with significantly increased mRNA expression during callus formation and maturation. Expression of VEGF mRNA was characterized by a more gradual increase during callus formation. The protein level for VEGFR1 was below detection sensitivity during the initial healing phase. It was then restored to a stable level, detectable through the subsequent healing phases. Hence, the VEGFR1 protein levels partially mirrored the transcript expression profile. In comparison, the protein level of VEGFR2 increased gradually during the healing phases and peaked at callus maturation. This correlated well with the transcriptional expression of VEGFR2. Intact bone from age-matched male mice had considerable protein levels of VEGFR1 and VEGF, but no detectable VEGFR2. Together, these findings uncovered expression signatures of the VEGF-VEGFR axis in endochondral bone repair. PMID:20947709

  15. NASA/BLM Applications Pilot Test (APT), phase 2. Volume 1: Executive summary. [vegetation mapping and production estimation in northwestern Arizona

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Data from LANDSAT, low altitude color aerial photography, and ground visits were combined and used to produce vegetation cover maps and to estimate productivity of range, woodland, and forest resources in northwestern Arizona. A planning session, two workshops, and four status reviews were held to assist technology transfer from NASA. Computer aided digital classification of LANDSAT data was selected as a major source of input data. An overview is presented of the data processing, data collection, productivity estimation, and map verification techniques used. Cost analysis and digital LANDSAT digital products are also considered.

  16. Methods of analysis by the U.S. Geological Survey Organic Geochemistry Research Group : determination of selected herbicides and their degradation products in water using solid-phase extraction and gas chromatography/mass spectrometry

    USGS Publications Warehouse

    Kish, J.L.; Thurman, E.M.; Scribner, E.A.; Zimmerman, L.R.

    2000-01-01

    A method for the extraction and analysis of eight herbicides and five degradation products using solid-phase extraction from natural water samples followed by gas chromatography/mass spectrometry is presented in this report. This method was developed for dimethenamid; flufenacet; fluometuron and its degradation products, demethylfluometuron (DMFM), 3-(trifluromethyl)phenylurea (TFMPU), 3-(trifluromethyl)-aniline (TFMA); molinate; norflurazon and its degradation product, demethylnorflurazon; pendamethalin; the degradation product of prometryn, deisopropylprometryn; propanil; and trifluralin. The eight herbicides are used primarily in the southern United States where cotton, rice, and soybeans are produced. The exceptions are dimethenamid and flufenacet, which are used on corn in the Midwest. Water samples received by the U.S. Geological Survey's Organic Geochemistry Research Group in Lawrence, Kansas, are filtered to remove suspended particulate matter and then passed through disposable solid-phase extraction columns containing octadecyl-bonded porous silica (C-18) to extract the compounds. The herbicides and their degradation products are removed from the column by ethyl acetate elution. The eluate is evaporated under nitrogen, and components then are separated, identified, and quantified by injecting an aliquot of the concentrated extract into a high-resolution, fused-silica capillary column of a gas chromatograph/mass spectrometer under selected-ion mode. Method detection limits ranged from 0.02 to 0.05 ?g/L for all compounds with the exception of TFMPU, which has a method detection limit of 0.32 ?g/L. The mean absolute recovery is 107 percent. This method for the determination of herbicides and their degradation products is valuable for acquiring information about water quality and compound fate and transport in water.

  17. Combined application of normal and reversed-phase high-performance liquid chromatography to determining the group composition of aromatic hydrocarbons in petroleum products

    SciTech Connect

    Belous, E.F.; Lanin, S.N.; Nikitin, Yu.S.

    1995-01-01

    The quality and working characteristics of motor fuels essentially depend on the concentration of aromatic hydrocarbons (AHs). Therefore, the development of procedures for the group determination of aromatic hydrocarbons is an important and topical problem in the processing and quality control of petroleum products. The aim of this work was to improve the group separation and quantitative determination of monocyclic and bicyclic aromatic hydrocarbons (MAH and BAH) in light-end products.

  18. Injection molding as a one-step process for the direct production of pharmaceutical dosage forms from primary powders.

    PubMed

    Eggenreich, K; Windhab, S; Schrank, S; Treffer, D; Juster, H; Steinbichler, G; Laske, S; Koscher, G; Roblegg, E; Khinast, J G

    2016-05-30

    The objective of the present study was to develop a one-step process for the production of tablets directly from primary powder by means of injection molding (IM), to create solid-dispersion based tablets. Fenofibrate was used as the model API, a polyvinyl caprolactame-polyvinyl acetate-polyethylene glycol graft co-polymer served as a matrix system. Formulations were injection-molded into tablets using state-of-the-art IM equipment. The resulting tablets were physico-chemically characterized and the drug release kinetics and mechanism were determined. Comparison tablets were produced, either directly from powder or from pre-processed pellets prepared via hot melt extrusion (HME). The content of the model drug in the formulations was 10% (w/w), 20% (w/w) and 30% (w/w), respectively. After 120min, both powder-based and pellet-based injection-molded tablets exhibited a drug release of 60% independent of the processing route. Content uniformity analysis demonstrated that the model drug was homogeneously distributed. Moreover, analysis of single dose uniformity also revealed geometric drug homogeneity between tablets of one shot. PMID:27012981

  19. Dual-Color Monitoring Overcomes the Limitations of Single Bioluminescent Reporters in Fast-Growing Microbes and Reveals Phase-Dependent Protein Productivity during the Metabolic Rhythms of Saccharomyces cerevisiae

    PubMed Central

    Krishnamoorthy, Archana

    2015-01-01

    Luciferase is a useful, noninvasive reporter of gene regulation that can be continuously monitored over long periods of time; however, its use is problematic in fast-growing microbes like bacteria and yeast because rapidly changing cell numbers and metabolic states also influence bioluminescence, thereby confounding the reporter's signal. Here we show that these problems can be overcome in the budding yeast Saccharomyces cerevisiae by simultaneously monitoring bioluminescence from two different colors of beetle luciferase, where one color (green) reports activity of a gene of interest, while a second color (red) is stably expressed and used to continuously normalize green bioluminescence for fluctuations in signal intensity that are unrelated to gene regulation. We use this dual-luciferase strategy in conjunction with a light-inducible promoter system to test whether different phases of yeast respiratory oscillations are more suitable for heterologous protein production than others. By using pulses of light to activate production of a green luciferase while normalizing signal variation to a red luciferase, we show that the early reductive phase of the yeast metabolic cycle produces more luciferase than other phases. PMID:26162874

  20. Multiple headspace-solid-phase microextraction as a powerful tool for the quantitative determination of volatile radiolysis products in a multilayer food packaging material sterilized with γ-radiation.

    PubMed

    de Oliveira, Cristiane Patrícia; Rodriguez-Lafuente, Angel; Soares, Nilda de Fátima Ferreira; Nerin, Cristina

    2012-06-29

    A method consisting of multiple headspace solid-phase microextraction followed by gas chromatography-mass spectrometry analysis was developed and used to determine the main volatile radiolysis products formed by γ-irradiation of flexible multilayer food packaging samples. The developed method allows the use of solid-phase microextraction in the quantification of compounds from plastic solid samples. A screening of volatiles in the γ-irradiated and non-irradiated films was performed and 29 compounds were identified in the irradiated packaging, 17 of which were absent in the non-irradiated samples. The main volatile radiolysis products identified were: 1,3-di-tert-butylbenzene; 2,6-di-tert-butyl-1,4-benzoquinone; 4-tert-butyl-phenol and the off-odor compounds butanoic acid and valeric acid. These volatile radiolysis compounds were determined with the proposed method and the results are shown and discussed. Solid-liquid extraction and headspace solid-phase microextraction methods were also studied for comparative purposes. The automated solvent-free multiple HSPME technique here presented can be used to quantify the radiolysis compounds in irradiated plastic solid samples in a simple way with the advantages of being free from matrix influence and environmentally friendly. PMID:22609166

  1. Effect of the electron decay of metallic fission products on the chemical and phase compositions of an uranium-plutonium fuel irradiated by fast neutrons

    NASA Astrophysics Data System (ADS)

    Bondarenko, G. G.; Bulatov, G. S.; Gedgovd, K. N.; Lyubimov, D. Yu.; Yakushkin, M. M.

    2011-11-01

    After fast-neutron irradiation, uranium-plutonium nitride U0.8Pu0.2N is shown to acquire a complex structure consisting of a solid solution that is based on the nitrides of uranium, plutonium, americium, neptunium, zirconium, yttrium, and lanthanides and contains condensed phases U2N3, CeRu2, BaTe, Ba3N2, CsI, Sr3N2, LaSe, metallic molybdenum, technetium, and U(Ru, Rh, Pd)3 intermetallics. The contents and compositions of these phases are calculated at a temperature of 900 K and a burn-up fraction up to 14% (U + Pu). The change in the composition of the irradiated uranium-plutonium nitride is studied during the electron decay of metallic radionuclides. The kinetics of transformation of U103Ru3, 137CsI, 140Ba3N2, and 241PuN is calculated.

  2. Effects of randomized supplementation of methionine or alanine on cysteine and glutathione production during the early phase of treatment of children with edematous malnutrition123

    PubMed Central

    Green, Curtis O; Hsu, Jean W; Taylor-Bryan, Carolyn; Reid, Marvin; Forrester, Terrence; Jahoor, Farook

    2014-01-01

    Background: We have shown that a low glutathione concentration and synthesis rate in erythrocytes are associated with a shortage of protein-derived cysteine in children with edematous severe acute malnutrition (SAM). Objective: We tested the hypothesis that methionine supplementation may increase protein-derived cysteine and upregulate cysteine synthesis, thereby improving glutathione synthesis during the early treatment of edematous SAM. Design: The cysteine flux, its de novo synthesis and release from protein breakdown, and erythrocyte glutathione synthesis rate were measured in 12 children with edematous SAM in the fed state by using stable isotope tracers at 3 clinical phases as follows: 3 ± 1 d (±SE) [clinical phase 1 (CP1)], 8 ± 1 d [clinical phase 2 (CP2)], and 14 ± 2 d (clinical phase 3) after admission. Subjects were randomly assigned to receive equimolar supplements (0.5 mmol ⋅ kg−1 ⋅ d−1) of methionine or alanine (control) immediately after CP1. Results: In the methionine compared with the alanine group, cysteine flux derived from protein breakdown was faster at CP2 than CP1 (P < 0.05), and the change in plasma cysteine concentration from CP1 to CP2 was greater (P < 0.05). However, there was no evidence of a difference in cysteine de novo synthesis and its total flux or erythrocyte glutathione synthesis rate and concentration between groups. Conclusions: Methionine supplementation increased cysteine flux from body protein but had no significant effect on glutathione synthesis rates. Although cysteine is made from methionine, increased dietary cysteine may be necessary to partially fulfill its demand in edematous SAM because glutathione synthesis rates and concentrations were less than previous values shown at full recovery. This study was registered at clinicaltrials.gov as NCT00473031. PMID:24598154

  3. Effect of culture phasing and mannanase on production of cellulase and hemicellulase by mixed culture of Trichoderma reesei D 1-6 and Aspergillus wentii Pt 2804

    SciTech Connect

    Ghose, T.K.; Panda, T.; Bisaria, V.S.

    1985-09-01

    Significant increase in extracellular cellulase and hemicellulase activities was observed in the biosynthesis of cellulase enzyme in mixed culture fermentation of Trichoderma reesei D 1-6 and Aspergillus wentii Pt 2804 when the A. wentii inoculation was phased by 15 hours. The optimal conditions of fermentation by the mixed culture have been established. Presence of mannanase has been found to affect the release as well as activity of cellulase enzyme produced in mixed culture.

  4. Optimization of phase feeding of starter, grower, and finisher diets for male broilers by mixture experimental design: forty-eight-day production period.

    PubMed

    Roush, W B; Boykin, D; Branton, S L

    2004-08-01

    A mixture experiment, a variant of response surface methodology, was designed to determine the proportion of time to feed broiler starter (23% protein), grower (20% protein), and finisher (18% protein) diets to optimize production and processing variables based on a total production time of 48 d. Mixture designs are useful for proportion problems where the components of the experiment (i.e., length of time the diets were fed) add up to a unity (48 d). The experiment was conducted with day-old male Ross x Ross broiler chicks. The birds were placed 50 birds per pen in each of 60 pens. The experimental design was a 10-point augmented simplex-centroid (ASC) design with 6 replicates of each point. Each design point represented the portion(s) of the 48 d that each of the diets was fed. Formulation of the diets was based on NRC standards. At 49 d, each pen of birds was evaluated for production data including BW, feed conversion, and cost of feed consumed. Then, 6 birds were randomly selected from each pen for processing data. Processing variables included live weight, hot carcass weight, dressing percentage, fat pad percentage, and breast yield (pectoralis major and pectoralis minor weights). Production and processing data were fit to simplex regression models. Model terms determined not to be significant (P > 0.05) were removed. The models were found to be statistically adequate for analysis of the response surfaces. A compromise solution was calculated based on optimal constraints designated for the production and processing data. The results indicated that broilers fed a starter and finisher diet for 30 and 18 d, respectively, would meet the production and processing constraints. Trace plots showed that the production and processing variables were not very sensitive to the grower diet. PMID:15339000

  5. Protocol Development for the NASA-JSC Lunar-Mars Life Support Test Project (LMLSTP) Phase 3 Project: A Report on Baseline Studies at KSC for Continuous Salad Production

    NASA Technical Reports Server (NTRS)

    Goins, G. D.; Yorio, N. C.; Vivenzio, H. R.

    1998-01-01

    The Phase 3 Lunar-Mars Life Support Test Project (LMLSTP) was conducted in a 20-foot chamber at Johnson Space Center. The overall objective of the Phase 3 project was to conduct a 90-day regenerative life support system test involving 4 human subjects to demonstrate an integrated biological and physicochemical life support system. A secondary objective of the Phase 3 LMLSTP was to demonstrate the ability to produce salad-type vegetable by integration of a small benchtop growth chamber located within the crew habitat area. This small chamber, commercially manufactured as the Controlled Environment Research Ecosystem (CERES 2010(TM)), functioned as a means to continuously provide fresh lettuce crops for crew members. The CERES 2010(TM) growth chamber utilized hardware components developed for effective plant biomass production in spaceflight applications. These components included: (1) LED lighting; (2) Astroculture(TM) Root Trays; and (3) Zeoponic media. In planning for the LMLSTP Phase 3, a request was put forward for KSC scientists to generate a protocol for successful continuous planting, culturing, and harvesting of the salad-crop, lettuce. By conducting baseline tests with components of the CERES 2010(TM), a protocol was developed.

  6. Development of an Ultrasonic Phased Array System for Wellbore Integrity Evaluation and Near-Wellbore Fracture Network Mapping of Injection and Production Wells in Geothermal Energy Systems

    SciTech Connect

    Almansouri, Hani; Foster, Benjamin; Kisner, Roger A; Polsky, Yarom; Bouman, Charlie

    2016-01-01

    This paper documents our progress developing an ultrasound phased array system in combination with a model-based iterative reconstruction (MBIR) algorithm to inspect the health of and characterize the composition of the near-wellbore region for geothermal reservoirs. The main goal for this system is to provide a near-wellbore in-situ characterization capability that will significantly improve wellbore integrity evaluation and near well-bore fracture network mapping. A more detailed image of the fracture network near the wellbore in particular will enable the selection of optimal locations for stimulation along the wellbore, provide critical data that can be used to improve stimulation design, and provide a means for measuring evolution of the fracture network to support long term management of reservoir operations. Development of such a measurement capability supports current hydrothermal operations as well as the successful demonstration of Engineered Geothermal Systems (EGS). The paper will include the design of the phased array system, the performance specifications, and characterization methodology. In addition, we will describe the MBIR forward model derived for the phased array system and the propagation of compressional waves through a pseudo-homogenous medium.

  7. Assessing the utility of phase-space-localized basis functions: Exploiting direct product structure and a new basis function selection procedure

    NASA Astrophysics Data System (ADS)

    Brown, James; Carrington, Tucker

    2016-06-01

    In this paper we show that it is possible to use an iterative eigensolver in conjunction with Halverson and Poirier's symmetrized Gaussian (SG) basis [T. Halverson and B. Poirier, J. Chem. Phys. 137, 224101 (2012)] to compute accurate vibrational energy levels of molecules with as many as five atoms. This is done, without storing and manipulating large matrices, by solving a regular eigenvalue problem that makes it possible to exploit direct-product structure. These ideas are combined with a new procedure for selecting which basis functions to use. The SG basis we work with is orders of magnitude smaller than the basis made by using a classical energy criterion. We find significant convergence errors in previous calculations with SG bases. For sum-of-product Hamiltonians, SG bases large enough to compute accurate levels are orders of magnitude larger than even simple pruned bases composed of products of harmonic oscillator functions.

  8. Phase II Nuclide Partition Laboratory Study Influence of Cellulose Degradation Products on the Transport of Nuclides from SRS Shallow Land Burial Facilities

    SciTech Connect

    Serkiz, S.M.

    1999-10-04

    Degradation products of cellulosic materials (e.g., paper and wood products) can significantly influence the subsurface transport of metals and radionuclides. Codisposal of radionuclides with cellulosic materials in the E-Area slit trenches at the Savannah River Site (SRS) is, therefore, expected to influence nuclide fate and transport in the subsurface. Due to the complexities of these systems and the scarcity of site-specific data, the effects of cellulose waste loading and its subsequent influence on nuclide transport are not well established.

  9. EMG and force production of the flexor hallucis longus muscle in isometric plantarflexion and the push-off phase of walking.

    PubMed

    Péter, Annamária; Hegyi, András; Stenroth, Lauri; Finni, Taija; Cronin, Neil J

    2015-09-18

    Large forces are generated under the big toe in the push-off phase of walking. The largest flexor muscle of the big toe is the flexor hallucis longus (FHL), which likely contributes substantially to these forces. This study examined FHL function at different levels of isometric plantarflexion torque and in the push-off phase at different speeds of walking. FHL and calf muscle activity were measured with surface EMG and plantar pressure was recorded with pressure insoles. FHL activity was compared to the activity of the calf muscles. Force and impulse values were calculated under the big toe, and were compared to the entire pressed area of the insole to determine the relative contribution of big toe flexion forces to the ground reaction force. FHL activity increased with increasing plantarflexion torque level (F=2.8, P=0.024) and with increasing walking speed (F=11.608, P<0.001). No differences were observed in the relative contribution of the force under the big toe to the entire sole between different plantarflexion torque levels (F=0.836, P=0.529). On the contrary, in the push-off phase of walking, peak force under the big toe increased at a higher rate than force under the other areas of the plantar surface (F=3.801, P=0.018), implying a greater relative contribution to total force at faster speeds. Moreover, substantial differences were found between isometric plantarflexion and walking concerning FHL activity relative to that of the calf muscles, highlighting the task-dependant behaviour of FHL. PMID:26100463

  10. Introducing Organic Chemistry Students to Natural Product Isolation Using Steam Distillation and Liquid Phase Extraction of Thymol, Camphor, and Citral, Monoterpenes Sharing a Unified Biosynthetic Precursor

    ERIC Educational Resources Information Center

    McLain, Katherine A.; Miller, Kenneth A.; Collins, William R.

    2015-01-01

    Plants have provided and continue to provide the inspiration and foundation for modern medicines. Natural product isolation is a key component of the process of drug discovery from plants. The purpose of this experiment is to introduce first semester undergraduate organic chemistry students, who have relatively few lab techniques at their…

  11. Evaluation of selected chemical processes for production of low-cost silicon phase 2. silicon material task, low-cost silicon solar array project

    NASA Technical Reports Server (NTRS)

    Blocher, J. M., Jr.; Browning, M. F.; Rose, E. E.; Thompson, W. B.; Schmitt, W. A.; Fippin, J. S.; Kidd, R. W.; Liu, C. Y.; Kerbler, P. S.; Ackley, W. R.

    1978-01-01

    Progress from October 1, 1977, through December 31, 1977, is reported in the design of the 50 MT/year experimental facility for the preparation of high purity silicon by the zinc vapor reduction of silicon tetrachloride in a fluidized bed of seed particles to form a free flowing granular product.

  12. Identification and Toxicological Assessment of Thermal Degradation Products of Organic Constituents of Parts Comprising LLNL Design ARG Phase 2 Interim Report

    SciTech Connect

    Lipska, A.E.; Lopez, R.D.

    1999-10-27

    The goals of Phase II of the Non Rad Toxics Project were: (1) To identify and quantify the major chemicals comprising smoke from smoldering plastics most prevalent in the LLNL designed weapons as well as materials unique to LANL designed weapons and SANDIA parts found in the LLNL and LANL weapons; and (2) To perform toxic assessment of the identified chemicals using existing literature information or TOPKAT, a computer program designed for toxic assessment of organic and certain organo-metallic compounds. This project was in support of the ARG Program needs No.15, Table XI, Accident Response Group.

  13. D-Alanylation of Teichoic Acids and Loss of Poly-N-Acetyl Glucosamine in Staphylococcus aureus during Exponential Growth Phase Enhance IL-12 Production in Murine Dendritic Cells

    PubMed Central

    Lund, Lisbeth Drozd; Ingmer, Hanne; Frøkiær, Hanne

    2016-01-01

    Staphylococcus aureus is a major human pathogen that has evolved very efficient immune evading strategies leading to persistent colonization. During different stages of growth, S. aureus express various surface molecules, which may affect the immune stimulating properties, but very little is known about their role in immune stimulation and evasion. Depending on the growth phase, S. aureus may affect antigen presenting cells differently. Here, the impact of growth phases and the surface molecules lipoteichoic acid, peptidoglycan and poly-N-acetyl glucosamine on the induction of IL-12 imperative for an efficient clearance of S. aureus was studied in dendritic cells (DCs). Exponential phase (EP) S. aureus was superior to stationary phase (SP) bacteria in induction of IL-12, which required actin-mediated endocytosis and endosomal acidification. Moreover, addition of staphylococcal cell wall derived peptidoglycan to EP S. aureus stimulated cells increased bacterial uptake but abrogated IL-12 induction, while addition of lipoteichoic acid increased IL-12 production but had no effect on the bacterial uptake. Depletion of the capability to produce poly-N-acetyl glucosamine increased the IL-12 inducing activity of EP bacteria. Furthermore, the mutant dltA unable to produce D-alanylated teichoic acids failed to induce IL-12 but like peptidoglycan and the toll-like receptor (TLR) ligands LPS and Pam3CSK4 the mutant stimulated increased macropinocytosis. In conclusion, the IL-12 response by DCs against S. aureus is highly growth phase dependent, relies on cell wall D-alanylation, endocytosis and subsequent endosomal degradation, and is abrogated by receptor induced macropinocytosis. PMID:26872029

  14. Quarterly Research Performance Progress Report (2015 Q3). Ultrasonic Phased Arrays and Interactive Reflectivity Tomography for Nondestructive Inspection of Injection and Production Wells in Geothermal Energy Systems

    SciTech Connect

    Santos-Villalobos, Hector J; Polsky, Yarom; Kisner, Roger A; Johnson, Christi R; Collins, Case; Bouman, Charles; Abdulrahman, Hani; Foster, Benjamin

    2015-09-01

    For the past quarter, we have placed our effort in implementing the first version of the ModelBased Iterative Reconstruction (MBIR) algorithm, assembling and testing the electronics, designing transducers mounts, and defining our laboratory test samples. We have successfully developed the first implementation of MBIR for ultrasound imaging. The current algorithm was tested with synthetic data and we are currently making new modifications for the reconstruction of real ultrasound data. Beside assembling and testing the electronics, we developed a LabView graphic user interface (GUI) to fully control the ultrasonic phased array, adjust the time-delays of the transducers, and store the measured reflections. As part of preparing for a laboratory-scale demonstration, the design and fabrication of the laboratory samples has begun. Three cement blocks with embedded objects will be fabricated, characterized, and used to demonstrate the capabilities of the system. During the next quarter, we will continue to improve the current MBIR forward model and integrate the reconstruction code with the LabView GUI. In addition, we will define focal laws for the ultrasonic phased array and perform the laboratory demonstration. We expect to perform laboratory demonstration by the end of October 2015.

  15. Alternative glues for the production of ATLAS silicon strip modules for the Phase-II upgrade of the ATLAS Inner Detector

    NASA Astrophysics Data System (ADS)

    Poley, L.; Bloch, I.; Edwards, S.; Friedrich, C.; Gregor, I.-M.; Jones, T.; Lacker, H.; Pyatt, S.; Rehnisch, L.; Sperlich, D.; Wilson, J.

    2016-05-01

    The Phase-II upgrade of the ATLAS detector for the High Luminosity Large Hadron Collider (HL-LHC) includes the replacement of the current Inner Detector with an all-silicon tracker consisting of pixel and strip detectors. The current Phase-II detector layout requires the construction of 20,000 strip detector modules consisting of sensor, circuit boards and readout chips, which are connected mechanically using adhesives. The adhesive used initially between readout chips and circuit board is a silver epoxy glue as was used in the current ATLAS SemiConductor Tracker (SCT). However, this glue has several disadvantages, which motivated the search for an alternative. This paper presents a study of six ultra-violet (UV) cure glues and a glue pad for possible use in the assembly of silicon strip detector modules for the ATLAS upgrade. Trials were carried out to determine the ease of use, thermal conduction and shear strength. Samples were thermally cycled, radiation hardness and corrosion resistance were also determined. These investigations led to the exclusion of three UV cure glues as well as the glue pad. Three UV cure glues were found to be possible better alternatives than silver loaded glue. Results from electrical tests of first prototype modules constructed using these glues are presented.

  16. Rate and product measurements for the reactions of OH with I/sub 2/ and ICl at 298 K: separation of gas-phase and surface reaction components

    SciTech Connect

    Loewenstein, L.M.; Anderson, J.G.

    1985-12-05

    The kinetic behavior of OH with I/sub 2/ and ICl is reported within the context of a series of radical-halogen reactions to investigate the mechanism of such reactions through studies of reactivity trends. Atomic I and Cl products of the title reactions are measured by resolved resonance fluorescence vapor lamps. IO and ClO are detected by chemically converting them, using NO, to I and Cl, respectively. The rate constant of the reaction H + ICl has been measured at 298 K; its only product channel is I + HCl. Magnitudes of the rate constants of these OH reactions substantiate the reactivity trends in the OH-halogen system based on an electron-transfer mechanism from the highest occupied molecular orbital of the halogen to the lowest unoccupied orbital of the hydroxyl. The rapidity of the OH + I/sub 2/ reaction makes it a possible source of HOI for photochemical studies. 31 references, 11 figures, 2 tables.

  17. PHASE DETECTOR

    DOEpatents

    Kippenhan, D.O.

    1959-09-01

    A phase detector circuit is described for use at very high frequencies of the order of 50 megacycles. The detector circuit includes a pair of rectifiers inverted relative to each other. One voltage to be compared is applied to the two rectifiers in phase opposition and the other voltage to be compared is commonly applied to the two rectifiers. The two result:ng d-c voltages derived from the rectifiers are combined in phase opposition to produce a single d-c voltage having amplitude and polarity characteristics dependent upon the phase relation between the signals to be compared. Principal novelty resides in the employment of a half-wave transmission line to derive the phase opposing signals from the first voltage to be compared for application to the two rectifiers in place of the transformer commonly utilized for such purpose in phase detector circuits for operation at lower frequency.

  18. Calcination and solid state reaction of ceramic-forming components to provide single-phase ceramic product having fine particle size

    SciTech Connect

    Balachandran, U.; Poeppel, R.B.; Emerson, J.E.; Johnson, S.A.

    1990-09-28

    The invention consists of an improved method for the preparation of single phase, fine grained ceramic materials from precursor powder mixtures where at least one of the components of the mixture is an alkali earth carbonate. The process consists of heating the precursor powders in a partial vacuum under flowing oxygen and under conditions where the partial pressure of CO{sub 2} evolved during the calcination is kept to a very low level relative to the oxygen. The process has been found particularly suitable for the preparation of high temperature copper oxide superconducting materials such as YBa{sub 2}Cu{sub 3}O{sub x} ``123`` and YBa{sub 2}Cu{sub 4}O{sub 8} ``124``.

  19. Collection and conversion of silicon furnace waste gas into higher value products: Phase 3, 6 MW pilot plant dc closed furnace technology. Final report

    SciTech Connect

    Dosaj, V.D.

    1995-01-01

    The construction and operation of a 6 MW, closed dc furnace for smelting silicon was the primary focus of Phase 3. A 6 MW, dc closed furnace pilot plant was built in East Selkirk, Manitoba, Canada. The furnace is equipped with world`s most modern automatic control system used to control and monitor the process variables and operational data. This control system is suitable for commercial applications and could be used with either closed or open dc furnaces for smelting silicon or ferrosilicon. The construction was started in September 1990, and the facility was operational within 18 months. Following successful commissioning of the pilot plant in June 1992, twelve smelting test campaigns were conducted through November 1994.

  20. Citations of environmental issues associated with the production, transport, storage, distribution and use of natural gas. Topical report, January-December 1992. Phase 2

    SciTech Connect

    Friedman, D.; Perry, K.R.; O'Neal, J.; Coerr, S.

    1992-12-10

    The report analyzes the appearance frequency of environmental trends and issues in the natural gas literature over the period January, 1989 - February, 1992. The trends and issues of interest are those described in the project's Phase I report, Trends and Issues at the Research Horizon (GRI-92/0156, April, 1992). Citations identified in the literature search were fully characterized including such key parameters as: the nature of the environmental impact, whether it represented a problem or opportunity for the gas industry, and when the impact is likely to be felt. A database was created to analyze the 327 citations. A number of database sorts (two field intersections) were performed and these intersections counted. These counts are used as an indication of the relative importance of the various trends and issues according to the industry literature.

  1. The Slicer Activity of ARGONAUTE1 Is Required Specifically for the Phasing, Not Production, of Trans-Acting Short Interfering RNAs in Arabidopsis.

    PubMed

    Arribas-Hernández, Laura; Marchais, Antonin; Poulsen, Christian; Haase, Bettina; Hauptmann, Judith; Benes, Vladimir; Meister, Gunter; Brodersen, Peter

    2016-07-01

    ARGONAUTE1 (AGO1) mediates posttranscriptional silencing by microRNAs (miRNAs) and short interfering RNAS (siRNAs). AGO1-catalyzed RNA cleavage (slicing) represses miRNA targets, but current models also highlight the roles of slicing in formation of siRNAs and siRNA-AGO1 complexes. miRNA-guided slicing is required for biogenesis of phased, trans-acting siRNAs (tasiRNAs), whose cleaved precursor fragments are converted to double-stranded RNA by RNA-dependent RNA polymerase 6 (RDR6). In addition, unwinding of duplex siRNA bound to AGO1 requires passenger strand cleavage in vitro. In this study, we analyze how mutation of four metal ion-coordinating residues of Arabidopsis thaliana AGO1 affects slicer activity in vitro and siRNA function in vivo. We show that while all four residues are required for slicer activity, they do not contribute equally to catalysis. Moreover, passenger strand cleavage is required for assembly of active AGO1-siRNA complexes in vivo, and many AGO1-bound siRNAs are trimmed in the absence of slicer activity. Remarkably, seedlings defective in AGO1 slicer activity produce abundant siRNAs from tasiRNA loci in vivo. These siRNAs depend on RDR6 and SUPPRESSOR OF GENE SILENCING3, but unlike wild-type tasiRNAs, they are unphased. These results demonstrate that slicing is solely required for phase definition of tasiRNAs, and they strongly support recruitment of RDR6 by AGO1 rather than by cleavage fragments. PMID:27354557

  2. Production of Multimeric Prostate-Specific Membrane Antigen Small Molecule Radiotracers using a Solid-Phase 99mTc Pre-Loading Strategy

    PubMed Central

    Misra, Preeti; Humblet, Valerie; Pannier, Nadine; Maison, Wolfgang; Frangioni, John V.

    2008-01-01

    Small molecule ligands specific for prostate-specific membrane antigen (PSMA) have the potential to improve prostate cancer imaging. However, highly charged ligands are difficult to label with 99mTc and to purify. In this study, we present an adamantane-trimerized small molecule that has nanomolar binding to PSMA, but that also has 12 negative charges. Methods To convert this molecule into a clinically viable SPECT diagnostic, we have developed a simple, cartridge-based, solid-phase pre-labeling strategy that, within 25 minutes, converts readily available and inexpensive 99mTc-pertechnetate into a chemically pure complex, with a reactive N-hydroxysuccinimide (NHS) ester, in neat organic solvent. This stable intermediate can label any amine-containing small molecule or peptide with 99mTc in one step, with high specific activity, and without the need for HPLC. Results Solid-phase conversion of 99mTc-pertechnetate to 99mTc-MAS3-NHS could be completed in 25 minutes, with >99% radiochemical purity and with no co-ligands present. This intermediate was then conjugated to adamantane-trimerized GPI in one step with >95% yield, and no need for HPLC purification. The final molecule bound specifically to living human tumor cells expressing PSMA on their surface. Quantitative comparison was made among GPI monomer, GPI trimer, and their 99mTc derivatives. Conclusion Our study describes a simple cartridge-based conversion of 99mTc pertechnetate to a useful, pre-loaded NHS ester intermediate that takes only 25 minutes to prepare and results in >99% radiochemical purity. Using this chemistry, we produce a high specific activity, 99mTc-labeled, PSMA-targeted small molecule, and demonstrate gamma ray radioscintigraphic imaging of living human prostate cancer cells. PMID:17631555

  3. The Slicer Activity of ARGONAUTE1 Is Required Specifically for the Phasing, Not Production, of Trans-Acting Short Interfering RNAs in Arabidopsis[OPEN

    PubMed Central

    Marchais, Antonin; Poulsen, Christian; Hauptmann, Judith; Meister, Gunter

    2016-01-01

    ARGONAUTE1 (AGO1) mediates posttranscriptional silencing by microRNAs (miRNAs) and short interfering RNAS (siRNAs). AGO1-catalyzed RNA cleavage (slicing) represses miRNA targets, but current models also highlight the roles of slicing in formation of siRNAs and siRNA-AGO1 complexes. miRNA-guided slicing is required for biogenesis of phased, trans-acting siRNAs (tasiRNAs), whose cleaved precursor fragments are converted to double-stranded RNA by RNA-dependent RNA polymerase 6 (RDR6). In addition, unwinding of duplex siRNA bound to AGO1 requires passenger strand cleavage in vitro. In this study, we analyze how mutation of four metal ion-coordinating residues of Arabidopsis thaliana AGO1 affects slicer activity in vitro and siRNA function in vivo. We show that while all four residues are required for slicer activity, they do not contribute equally to catalysis. Moreover, passenger strand cleavage is required for assembly of active AGO1-siRNA complexes in vivo, and many AGO1-bound siRNAs are trimmed in the absence of slicer activity. Remarkably, seedlings defective in AGO1 slicer activity produce abundant siRNAs from tasiRNA loci in vivo. These siRNAs depend on RDR6 and SUPPRESSOR OF GENE SILENCING3, but unlike wild-type tasiRNAs, they are unphased. These results demonstrate that slicing is solely required for phase definition of tasiRNAs, and they strongly support recruitment of RDR6 by AGO1 rather than by cleavage fragments. PMID:27354557

  4. Investigation of fragrance stability used in the formulation of cosmetic and hygienic products using headspace solid-phase microextraction by nanostructured materials followed by gas chromatography with mass spectrometry.

    PubMed

    Masoum, Saeed; Gholami, Ali; Ghaheri, Salehe; Bouveresse, Delphine Jouan-Rimbaud; Cordella, Christophe B Y; Rutledge, Douglas N

    2016-07-01

    A new composite coating of polypyrrole and sodium lauryl ether sulfate was electrochemically prepared on a stainless-steel wire using cyclic voltammetry. The application and performance of the fiber was evaluated for the headspace solid-phase microextraction of a fragrance in aqueous bleach samples followed by gas chromatography combined with mass spectrometry to assess the fragrance stability in this kind of household cleaning product. To obtain a stable and efficient composite coating, parameters related to the coating process such as scan rate and numbers of cycles were optimized using a central composite design. In addition, the effects of various parameters on the extraction efficiency of the headspace solid-phase microextraction process such as extraction temperature and time, ionic strength, sample volume, and stirring rate were investigated by experimental design methods using Plackett-Burman and Doehlert designs. The optimum values of 53°C and 28 min for sample temperature and time, respectively, were found through response surface methodology. Results show that the combination of polypyrrole and sodium lauryl ether sulfate in a composite form presents desirable opportunities to produce new materials to study fragrance stability by headspace solid-phase microextraction. PMID:27219290

  5. Mechanism and dynamics of the reaction of XeF2 with fluorinated Si(100): possible role of gas phase dissociation of a surface reaction product in plasmaless etching.

    PubMed

    Hefty, R C; Holt, J R; Tate, M R; Ceyer, S T

    2009-04-28

    Xenon difluoride is observed to react with Si-Si sigma-dimer and sigma-lattice bonds of Si(100)2 x 1 at 150 K by single and two atom abstraction at F coverages above 1 ML. As in the limit of zero F coverage, a measurable fraction of the scattered, gas phase product of single atom abstraction, XeF, is sufficiently internally excited to dissociate into F and Xe atoms before detection. Using the XeF internal energy and orientation distributions determined in the limit of zero coverage, the laws of conservation of momentum, energy, and mass are applied to the measured F velocity and angular distributions at higher coverage to simulate the Xe atom velocity and angular distributions and their intensities at higher coverage. The simulation predicts the observed Xe atom velocity and angular distributions at high coverage reasonably well, largely because the exothermicity channeled to XeF remains approximately constant as the coverage increases. This constancy is an opportune consequence of the trade-off between the attractiveness of the potential energy surface as the coverage is increased and the dynamics of the XeF product along the potential surface. The energy, momentum, and mass conservation analysis is also used to distinguish between Xe atoms that arise from XeF gas phase dissociation and Xe atoms that are produced by two atom abstraction. This distinction enables the calculation of percentages of the single and two atom abstraction pathways, as well as the percentages of the two pathways available to the Xe atom produced by two atom abstraction, inelastic scattering, and desorption. Finally, the simulation reveals that between 9% and 12% of F atoms produced by gas phase dissociation of XeF are scattered back toward the surface. These F atoms likely react readily with Si to form the higher fluorides that ultimately lead to etching. Gas phase dissociation of the scattered product of a surface reaction is a novel mechanism to explain the unique reactivity of XeF(2) to

  6. Methods of analysis by the U.S. Geological Survey Organic Geochemistry Research Group : determination of triazine and phenylurea herbicides and their degradation products in water using solid-phase extraction and liquid chromatography/mass spectrometry

    USGS Publications Warehouse

    Lee, Edward Alan; Strahan, Alex P.; Thurman, Earl Michael

    2002-01-01

    An analytical method for the determination of 7 triazine and phenylurea herbicides and 12 of their degradation products in natural water samples using solid-phase extraction and liquid chromatography/mass spectrometry is presented in this report. Special consideration was given during the development of the method to prevent the formation of degradation products during the analysis. Filtered water samples were analyzed using 0.5 gram graphitized carbon as the solid-phase extraction media followed by liquid chromatography/mass spectrometry. Three different water-sample matrices?ground-water, surface-water, and reagent-water samples?spiked at 0.2 and 2.0 micrograms per liter were analyzed. Method detection limits ranged from 0.013 to 0.168 microgram per liter for the parent triazine herbicides and the triazine degradation products. Method detection limits ranged from 0.042 to 0.141 microgram per liter for the parent phenylurea herbicides and their degradation products. Mean recoveries for the triazine compounds in the ground- and surface-water samples generally ranged from 72.6 to 117.5 percent, but deethyl-cyanazine amide was recovered at 140.5 percent. Mean recoveries from the ground- and surface-water samples for the phenylurea compounds spiked at the 2.0-micrograms-per-liter level ranged from 82.1 to 114.4 percent. The mean recoveries for the phenylureas spiked at 0.2-microgram per liter were less consistent, ranging from 87.0 to 136.0 percent. Mean recoveries from reagent-water samples ranged from 87.0 to 109.5 percent for all compounds. The triazine compounds and their degradation products are reported in concentrations ranging from 0.05 to 2.0 micrograms per liter, with the exception of deethylcyanazine and deethylcyanazine amide which are reported at 0.20 to 2.0 micrograms per liter. The phenylurea compounds and their degradation products are reported in concentrations ranging from 0.20 to 2.0 micrograms per liter. The upper concentration limit was 2

  7. Laboratory Studies of Stabilities of Heterocyclic Aromatic Molecules: Suggested Gas Phase Ion-Molecule Routes to Production in Interstellar Gas Clouds

    NASA Astrophysics Data System (ADS)

    Adams, N. G.; Fondren, L. D.; McLain, J. L.; Jackson, D. M.

    Several ring compounds have been detected in interstellar gas clouds, ISC, including the aromatic, benzene. Polycyclic aromatic hydrocarbons, PAH's, have been implicated as carriers of diffuse interstellar bands (DIB's) and unidentified infrared (UIR) bands. Heterocyclic aromatic rings of intermediate size containing nitrogen, possibly PreLife molecules, were included in early searches but were not detected and a recent search for Pyrimidine was unsuccessful. Our laboratory investigations of routes to such molecules could establish their existence in ISC and suggest conditions under which their concentrations would be maximized thus aiding the searches. The stability of such ring compounds (C_5H_5N, C_4H_4N_2, C_5H_{11}N and C_4H_8O_2) has been tested in the laboratory using charge transfer excitation in ion-molecule reactions. The fragmentation paths, including production of C_4H_4^+, C_3H_3N^+ and HCN, suggest reverse routes to the parent molecules, which are presently under laboratory investigation as production sources.

  8. Application of the CALIOP Layer Product to Evaluate the Vertical Distribution of Aerosols Estimated by Global Models: AeroCom Phase I Results

    SciTech Connect

    Koffi, Brigitte; Schultz, Michael; Breon, Francois-Marie; Griesfeller, Jan; Winker, D.; Balkanski, Y.; Bauer, Susanne E.; Berntsen, T.; Chin, Mian; Collins, William D.; Dentener, Frank; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Ginoux, P.; Gong, S.; Horowitz, L.; Iversen, T.; Kirkevag, A.; Koch, Dorothy; Krol, Maarten; Myhre, G.; Stier, P.; Takemura, T.

    2012-05-19

    The CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) layer product is used for a multimodel evaluation of the vertical distribution of aerosols. Annual and seasonal aerosol extinction profiles are analyzed over 13 sub-continental regions representative of industrial, dust, and biomass burning pollution, from CALIOP 2007-2009 observations and from AeroCom (Aerosol Comparisons between Observations and Models) 2000 simulations. An extinction mean height diagnostic (Z{sub a}) is defined to quantitatively assess the models performance. It is calculated over the 0-6 km and 0-10 km altitude ranges by weighting the altitude of each 100 m altitude layer by its aerosol extinction coefficient. The mean extinction profiles derived from CALIOP layer products provide consistent regional and seasonal specificities and a low inter-annual variability. While the outputs from most models are significantly correlated with the observed Z{sub a} climatologies, some do better than others, and 2 of the 12 models perform particularly well in all seasons. Over industrial and maritime regions, most models show higher Z{sub a} than observed by CALIOP, whereas over the African and Chinese dust source regions, Z{sub a} is underestimated during Northern Hemisphere Spring and Summer. The positive model bias in Z{sub a} is mainly due to an overestimate of the extinction above 6 km. Potential CALIOP and model limitations, and methodological factors that might contribute to the differences are discussed.

  9. Effects of temperature and nutrient regimes on biomass and lipid production by six oleaginous microalgae in batch culture employing a two-phase cultivation strategy.

    PubMed

    Roleda, Michael Y; Slocombe, Stephen P; Leakey, Raymond J G; Day, John G; Bell, Elanor M; Stanley, Michele S

    2013-02-01

    Commercial success of algal-based biofuels depends on growth characteristics and lipid metabolism of the production species. The oleaginous microalgae, Thalassiosira pseudonana, Odontella aurita, Nannochloropsis oculata, Isochrysis galbana, Chromulina ochromonoides, and Dunaliella tertiolecta, were cultivated under a matrix of two temperatures (10 and 20 °C) and two nutrient regimes (deplete and replete). For all species, a strong negative correlation between growth rate and lipid content was observed. Multiple stressors have no additive effect on lipid accumulation. Total oil content (fatty acid methyl esters, FAMEs, pg cell(-1)) was increased more by nutrient limitation than by temperature stress. In response to nutrient stress, N. oculata emerged as the most robust species with an increase in lipid accumulation of up to three to four-fold compared to the accumulation under nutrient sufficient conditions. Although stress conditions led to reduced fatty acid unsaturation in most taxa due to increased triacylglycerol (TAG) production, a high proportion of eicosapentaenoic acid (EPA) was maintained in O. aurita. PMID:23262022

  10. Application of the CALIOP Layer Product to Evaluate the Vertical Distribution of Aerosols Estimated by Global Models: AeroCom Phase I Results

    NASA Technical Reports Server (NTRS)

    Koffi, Brigitte; Schulz, Michael; Breon, Francois-Marie; Griesfeller, Jan; Winker, David; Balkanski, Yves; Bauer, Susanne; Berntsen, Terje; Chin, Mian; Collins, William D.; Dentener, Frank; Diehl, Thomas; Easter, Richard; Ghan, Steven; Gimoux, Paul; Gong, Sunling; Horowitz, Larry W.; Iversen, Trond; Kirkevag, Alf; Koch, Dorothy; Krol, Maarten; Myhre, Gunnar; Stier, Philip; Takemura, Toshihiko

    2012-01-01

    The CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) layer product is used for a multimodel evaluation of the vertical distribution of aerosols. Annual and seasonal aerosol extinction profiles are analyzed over 13 sub-continental regions representative of industrial, dust, and biomass burning pollution, from CALIOP 2007-2009 observations and from AeroCom (Aerosol Comparisons between Observations and Models) 2000 simulations. An extinction mean height diagnostic (Z-alpha) is defined to quantitatively assess the models' performance. It is calculated over the 0-6 km and 0-10 km altitude ranges by weighting the altitude of each 100 m altitude layer by its aerosol extinction coefficient. The mean extinction profiles derived from CALIOP layer products provide consistent regional and seasonal specificities and a low inter-annual variability. While the outputs from most models are significantly correlated with the observed Z-alpha climatologies, some do better than others, and 2 of the 12 models perform particularly well in all seasons. Over industrial and maritime regions, most models show higher Z-alpha than observed by CALIOP, whereas over the African and Chinese dust source regions, Z-alpha is underestimated during Northern Hemisphere Spring and Summer. The positive model bias in Z-alpha is mainly due to an overestimate of the extinction above 6 km. Potential CALIOP and model limitations, and methodological factors that might contribute to the differences are discussed.

  11. Laboratory Studies of Stabilities of Heterocyclic Aromatic Molecules: Suggested Gas Phase Ion-Molecule Routes to Production in Interstellar Gas Clouds

    NASA Technical Reports Server (NTRS)

    Adams, Nigel G.; Fondren, L. Dalila; McLain, Jason L.; Jackson, Doug M.

    2006-01-01

    Several ring compounds have been detected in interstellar gas clouds, ISC, including the aromatic, benzene. Polycyclic aromatic hydrocarbons, PAHs, have been implicated as carriers of diffuse interstellar bands (DIBs) and unidentified infrared (UIR) bands. Heterocyclic aromatic rings of intermediate size containing nitrogen, possibly PreLife molecules, were included in early searches but were not detected and a recent search for Pyrimidine was unsuccessful. Our laboratory investigations of routes to such molecules could establish their existence in ISC and suggest conditions under which their concentrations would be maximized thus aiding the searches. The stability of such ring compounds (C5H5N, C4H4N2, C5H11N and C4H8O2) has been tested in the laboratory using charge transfer excitation in ion-molecule reactions. The fragmentation paths, including production of C4H4(+), C3H3N(+) and HCN, suggest reverse routes to the parent molecules, which are presently under laboratory investigation as production sources.

  12. Thermodynamics of Highly Supersaturated Aqueous Solutions of Poorly Water-Soluble Drugs-Impact of a Second Drug on the Solution Phase Behavior and Implications for Combination Products.

    PubMed

    Trasi, Niraj S; Taylor, Lynne S

    2015-08-01

    There is increasing interest in formulating combination products that contain two or more drugs. Furthermore, it is also common for different drug products to be taken simultaneously. This raises the possibility of interactions between different drugs that may impact formulation performance. For poorly water-soluble compounds, the supersaturation behavior may be a critical factor in determining the extent of oral absorption. The goal of the current study was to evaluate the maximum achievable supersaturation for several poorly water-soluble compounds alone, and in combination. Model compounds included ritonavir, lopinavir, paclitaxel, felodipine, and diclofenac. The "amorphous solubility" for the pure drugs was determined using different techniques and the change in this solubility was then measured in the presence of differing amounts of a second drug. The results showed that "amorphous solubility" of each component in aqueous solution is substantially decreased by the second component, as long as the two drugs are miscible in the amorphous state. A simple thermodynamic model could be used to predict the changes in solubility as a function of composition. This information is of great value when developing co-amorphous or other supersaturating formulations and should contribute to a broader understanding of drug-drug physicochemical interactions in in vitro assays as well as in the gastrointestinal tract. PMID:26059413

  13. Production of aluminum-silicon alloy and ferrosilicon and commercial purity aluminum by the direct reduction process. First interim technical report, Phase D, January 1-March 31, 1981

    SciTech Connect

    Bruno, M.J.

    1981-04-01

    Operation of the bench AF-reactor on burden with all reducing carbon exterior to the ore pellet resulted in low metal alloy product yields and prematurely terminated runs, indicating the need for intimate contact between alumina and carbon to produce oxycarbide liquid prior to reaction with solid silicon carbide. Carbon solubility tests made on 60Al-40Si alloys at 2200/sup 0/C in graphite crucibles indicated continued reaction to form SiC for one hour. Efficiency of reduction to SiC ranged from 68 to 100%. The A-C two-electrode submerged arc reactor pilot, SAR-II, was successfully operated on both alumina-clay-coke and alumina-silicon carbide-coke (from the VSR prereduction) burdens. Metal alloy was produced and tapped in each of four runs. The pilot crystallizer was operated to evalute the two-stage (stop and go) crystallization technique on obtaining high yields of Al in Al-Si eutectic, with a limit of 1.0% Fe and 0.1% Ti in the alloy product. 18 figures, 19 tables. (DLC)

  14. Production de faisceaux EPR à l'aide d'un oscillateur paramétrique optique à auto-verrouillage de phase

    NASA Astrophysics Data System (ADS)

    Longchambon, L.; Laurat, J.; Treps, N.; Ducci, S.; Maître, A.; Coudreau, T.; Fabre, C.

    2002-06-01

    Nous étudions théoriquement les propriétés quantiques des faisceaux lumineux continus orthogonalement polarisés émis par un Oscillateur Paramétrique Optique (OPO) de type II contenant une lame biréfringente. Quand les axes optiques de la lame sont tournés par rapport à ceux du cristal paramétrique, un couplage apparaît entre les faisceaux signal et complémentaire qui entraîne un verrouillage de phase entre les deux modes et un fonctionnement à dégénérescence de fréquence à l'intérieur d'une zone d'accrochage. Les corrélations quantiques entre les deux faisceaux permettent de définir les zones dans l'espace des paramètres expérimentaux où les différents critères associés à l'intrication EPR utilisés en information quantique sont vérifiés.

  15. Synthesis of cis-C-Iodo-N-Tosyl-Aziridines using Diiodomethyllithium: Reaction Optimization, Product Scope and Stability, and a Protocol for Selection of Stationary Phase for Chromatography

    PubMed Central

    2013-01-01

    The preparation of C-iodo-N-Ts-aziridines with excellent cis-diastereoselectivity has been achieved in high yields by the addition of diiodomethyllithium to N-tosylimines and N-tosylimine–HSO2Tol adducts. This addition-cyclization protocol successfully provided a wide range of cis-iodoaziridines, including the first examples of alkyl-substituted iodoaziridines, with the reaction tolerating both aryl imines and alkyl imines. An ortho-chlorophenyl imine afforded a β-amino gem-diiodide under the optimized reaction conditions due to a postulated coordinated intermediate preventing cyclization. An effective protocol to assess the stability of the sensitive iodoaziridine functional group to chromatography was also developed. As a result of the judicious choice of stationary phase, the iodoaziridines could be purified by column chromatography; the use of deactivated basic alumina (activity IV) afforded high yield and purity. Rearrangements of electron-rich aryl-iodoaziridines have been promoted, selectively affording either novel α-iodo-N-Ts-imines or α-iodo-aldehydes in high yield. PMID:23738857

  16. Crystalline phase transition of ezetimibe in final product, after packing, promoted by the humidity of excipients: Monitoring and quantification by Raman spectroscopy.

    PubMed

    Farias, Marco Antônio Dos Santos; Soares, Frederico Luis Felipe; Carneiro, Renato Lajarim

    2016-03-20

    Ezetimibe (EZT), in its anhydrous form, is a drug used for cholesterol and lipids reduction in blood plasma. The presence of EZT monohydrate in commercial tablets can change the solubility rate of the API, decreasing its activity. The objective of this work was to verify if the humidity present in the excipients could promote the phase transition from EZT anhydrous to hydrate. Initially the stability of the pure anhydrous form was monitored by Raman, at room temperature (23°C) and relative humidity (75%). The MCR-ALS method showed that almost all EZT changed to hydrated form in 30min. Then tablets of ezetimibe in the presence of its excipients were prepared and vacuum packed using a polyethylene film. Such tablet was monitored by Raman spectroscopy for 24h in order to quantify the mixture of the crystalline forms. A multivariate calibration model using Raman spectroscopy and Partial Least Square (PLS) regression was built, with validation and cross validation errors around 0.6% (wt/wt), for both crystalline forms, and R(2) higher than 0.96. The PLS model was used to quantify the crystalline mixture of ezetimibe in the monitored tablet, after 24h more than 70% of ezetimibe changed to the hydrated form. PMID:26812479

  17. Engineer, design, construct, test and evaluate a pressurized fluidized bed pilot plant using high sulfur coal for production of electric power. Phase III. Pilot plant construction. Final report

    SciTech Connect

    Not Available

    1984-11-01

    This final report describes the coal-fired plant design capable of producing electric power in an environmentally clean manner. The report presents the predicted performance using high sulfur bituminous coal and summarizes the construction activities and changes through completion on November 30, 1983. The construction activities involved: (1) the site excavation and pouring foundations for the PFB process equipment structural tower, control building, dolomite silo, boost compressor, and various equipment footings; (2) the fabrication and erection of the support steel work for the process equipment tower, control building, rail car thaw shed, and particulate scrubber and exhaust stack; (3) the fabrication and erection of the process equipment including the PFB combustor vessel, windbox, in-bed heat exchanger and process piping, the ash recycle system, the gas clean-up system, the ash removal, cooling and storage system, the coal handling, preparation and injection systems, the dolomite receiving, handling, storage and injection systems, the boost air compressor, dryer and receiver systems, the purge instrument and service air systems, the control, instrument and electrical systems, the tower elevator, the cardox, Halon and water fire protection system, etc. In addition, modifications and refurbishment were completed on the existing equipment at the site which was incorporated into the Pilot Plant system. Finally, plans were prepared describing the operating procedures, maintenance requirements, spare parts list, training program and manpower requirements for the proposed Phase IV test evaluation program. 37 figures, 11 tables.

  18. Application of multiwalled carbon nanotubes modified by diphenylcarbazide for selective solid phase extraction of ultra traces Cd(II) in water samples and food products.

    PubMed

    Behbahani, Mohammad; Bagheri, Akbar; Amini, Mostafa M; Sadeghi, Omid; Salarian, Mani; Najafi, Fatemeh; Taghizadeh, Mohsen

    2013-11-01

    A novel sorbent for separation of cadmium ions was prepared by functionalizing multiwall carbon nanotubes with diphenylcarbazide and underutilised to develop a solid-phase extraction method to separate and concentrate trace amounts of cadmium ions from some real samples by flame atomic absorption spectrophotometry measurements. The optimum experimental conditions such as pH, flow rates, type and the smallest amount of eluent for elution of cadmium ions, break through volume and effect of coexisting ions on the separation and determination of cadmium ions were evaluated. In the proposed method, the extraction efficiency for cadmium ions were greater than 97% and limit of detection (LOD) was 0.05 ng mL(-1). The preconcentration factor was 360 for cadmium and the relative standard deviation (RSD) of the method was 2.4%. The adsorption capacity of the modified MWCNT was 86 mg g(-1) for cadmium ions. Validation of the outlined method was performed by analysing certified reference material soil (NCS DC 73323). The practical applicability of the developed sorbent was examined in some real samples. PMID:23768325

  19. High volume-high value usage of flue gas desulfurization (FGD) by-products in underground mines: Phase 2 -- Field investigations. Quarterly report, October 1--December 31, 1997

    SciTech Connect

    1998-08-01

    The field investigation phase of the project was essentially completed when grout placed into auger holes at the Lodestar Energy mine site during Summer 1997 was sampled. Mining had proceeded to a point where the strata overlying the coal was completely removed, thus exposing the grout-filled auger holes. All of the auger holes contained either grout from these experiments or shale that in-filled the non-grouted holes during the process of clearing the top surface of the coal. Eleven grouted holes were sampled, utilizing hammers and chisels, for physical (strength) testing, as well as chemical, mineralogical, and microscopical analysis. Upon arrival at the laboratory, moisture contents, densities, and void ratios were obtained before disturbing the samples, and after strength testing. Representative samples of each grout were then cut into flat-sided prisms, with a height:width ratio {approx}2, to be used for testing of unconfined compressive strength. In summary, all of the grouts had very good mechanical strength, ranging from 1000 psi to 2250 psi. The lowest compressive strength was recorded on a bed ash-based grout.

  20. A Novel Photocatalyst with Ferromagnetic Core Used for the Treatment of Olive Oil Mill Effluents from Two-Phase Production Process

    PubMed Central

    Ochando-Pulido, Javier Miguel; Víctor-Ortega, María Dolores; Martínez-Ferez, Antonio

    2013-01-01

    Photocatalytic degradation of olive oil mill wastewater from two-phase continuous centrifugation process was studied. A novel photocatalyst with ferromagnetic properties was characterized and investigated. The degradation capacity of the photocatalytic process of olive oil washing wastewater (OMW) and mixture of olives and olive oil (1 v/v) washing wastewaters (MOMW) was demonstrated. At lab-scale, the %COD removal and residence time (τ) for MOMW and OMW were 58.4% (τ = 2 h) and 21.4% (τ = 3 h), respectively. On the other hand, at pilot scale, 23.4% CODremoval, 19.2% total phenolsremoval, and 28.1% total suspended solidsremoval were registered at the end of the UV/TiO2 process for OMW, whereas 58.3% CODremoval, 27.5% total phenolsremoval, and 25.0% total suspended solidsremoval for MOMW. Also, before the UV/TiO2 reaction, a pH-T flocculation operation as pretreatment was realized. The overall efficiency of the treatment process for MOMW was up to 91% of CODremoval, in contrast with 33.2% of CODremoval for OMW. PMID:24489490