Science.gov

Sample records for 3m empore carbon

  1. Solid-phase extraction of polar pesticides from environmental water samples on graphitized carbon and Empore-activated carbon disks and on-line coupling to octadecyl-bonded silica analytical columns.

    PubMed

    Slobodník, J; Oztezkizan, O; Lingeman, H; Brinkman, U A

    1996-10-25

    The suitability of Empore-activated carbon disks (EACD), Envi-Carb graphitized carbon black (GCB) and CPP-50 graphitized carbon for the trace enrichment of polar pesticides from water samples was studied by means of off-line and on-line solid-phase extraction (SPE). In the off-line procedure, 0.5-2 l samples spiked with a test mixture of oxamyl, methomyl and aldicarb sulfoxide were enriched on EnviCarb SPE cartridges or 47 mm diameter EACD and eluted with dichloromethane-methanol. After evaporation, a sample was injected onto a C18-bonded silica column and analysed by liquid chromatography with ultraviolet (LC-UV) detection. EACD performed better than EnviCarb cartridges in terms of breakthrough volumes (> 2 l for all test analytes), reproducibility (R.S.D. of recoveries, 4-8%, n = 3) and sampling speed (100 ml/min); detection limits in drinking water were 0.05-0.16 microgram/l. In the on-line experiments, 4.6 mm diameter pieces cut from original EACD and stacked onto each other in a 9 mm long precolumn, and EnviCarb and CPP-50 packed in 10 x 2.0 mm I.D. precolumn, were tested, and 50-200 ml spiked water samples were preconcentrated. Because of the peak broadening caused by the strong sorption of the analytes on carbon, the carbon-packed precolumns were eluted by a separate stream of 0.1 ml/min acetonitrile which was mixed with the gradient LC eluent in front of the C18 analytical column. The final on-line procedure was also applied for the less polar propoxur, carbaryl and methiocarb. EnviCarb could not be used due to its poor pressure resistance. CPP-50 provided less peak broadening than EACD: peak widths were 0.1-0.3 min and R.S.D. of peak heights 4-14% (n = 3). In terms of analyte trapping efficiency on-line SPE-LC-UV with a CPP-50 precolumn also showed better performance than when Bondesil C18/OH or polymeric PLRP-S was used, but chromatographic resolution was similar. With the CPP-50-based system, detection limits of the test compounds were 0.05-1 microgram

  2. Quantitative determination of total molar concentrations of bioaccumulatable organic micropollutants in water using C18 empore disk and molar detection techniques.

    PubMed

    van Loon, W M; Wijnker, F G; Verwoerd, M E; Hermens, J L

    1996-09-01

    A highly sensitive and quantitative group parameter to determine total molar concentrations of organic micropollutants that can bioaccumulate in the lipid phase of aquatic organisms from effluents, surface water, and drinking water has been developed. C18 empore disk was used as a surrogate lipid phase. The partition process between water and C18 empore disk was employed to simulate the bioaccumulation process. After partition extraction of the water sample, the empore disk was extracted with cyclohexane, and total molar concentrations were determined in these extracts using vapor pressure osmometry (VPO) and gas chromatography/mass spectrometry (GC/MS), respectively. Total molar concentrations bioaccumulated in aquatic biota were estimated from the cyclohexane concentrations. Good accuracy for the total molar determination was obtained using VPO, due to the practically constant molar response factors (43.1 +/- 1.7 V/M) for a wide compound range and to excellent additivity of individual compound responses. Satisfying reproducibility (0-8.3%) of VPO was obtained for sample extracts. The detection limit of VPO in cyclohexane extracts corresponded to 0.60 mM in the lipid phase of aquatic biota. A minimal separation GC/MS system was developed, which enabled highly sensitive and sufficiently accurate total molar determinations. The reproducibility of the GC/MS determination for samples ranged from 0.7 to 22%. The detection limit of GC/MS in cyclohexane extracts corresponded to 0.044 mM in the lipid phase. The determined total molar concentrations in the lipid phase of aquatic biota were in the range of 0.139-168 mM for effluents, 0.26-1.34 mM for surface water systems, and < 0.044 mM for drinking water.

  3. Short communication: a new dataset for estimating organic carbon storage to 3 m depth in soils of the northern circumpolar permafrost region

    NASA Astrophysics Data System (ADS)

    Hugelius, G.; Tarnocai, C.; Bockheim, J. G.; Camill, P.; Elberling, B.; Grosse, G.; Harden, J. W.; Johnson, K.; Jorgenson, T.; Koven, C. D.; Kuhry, P.; Michaelson, G.; Mishra, U.; Palmtag, J.; Ping, C.-L.; O'Donnell, J.; Schirrmeister, L.; Schuur, E. A. G.; Sheng, Y.; Smith, L. C.; Strauss, J.; Yu, Z.

    2013-04-01

    High latitude terrestrial ecosystems are key components in the global carbon (C) cycle. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify stocks of soil organic carbon (SOC) in the northern circumpolar permafrost region (18.7 × 106 km2). The NCSCD is a digital Geographical Information systems (GIS) database compiled from harmonized regional soil classification maps, in which data on soil coverage has been linked to pedon data from the northern permafrost regions. Previously, the NCSCD has been used to calculate SOC content (SOCC) and mass (SOCM) to the reference depths 0-30 cm and 0-100 cm (based on 1778 pedons). It has been shown that soils of the northern circumpolar permafrost region also contain significant quantities of SOC in the 100-300 cm depth range, but there has been no circumpolar compilation of pedon data to quantify this SOC pool and there are no spatially distributed estimates of SOC storage below 100 cm depth in this region. Here we describe the synthesis of an updated pedon dataset for SOCC in deep soils of the northern circumpolar permafrost regions, with separate datasets for the 100-200 cm (524 pedons) and 200-300 cm (356 pedons) depth ranges. These pedons have been grouped into the American and Eurasian sectors and the mean SOCC for different soil taxa (subdivided into Histels, Turbels, Orthels, Histosols, and permafrost-free mineral soil taxa) has been added to the updated NCSCDv2. The updated version of the database is freely available online in several different file formats and spatial resolutions that enable spatially explicit usage in e.g. GIS and/or terrestrial ecosystem models. The potential applications and limitations of the NCSCDv2 in spatial analyses are briefly discussed. An open access data-portal for all the described GIS-datasets is available online at: http://dev1.geo.su.se/bbcc/dev/v3/ncscd/download.php. The NCSCDv2

  4. A new data set for estimating organic carbon storage to 3 m depth in soils of the northern circumpolar permafrost region

    USGS Publications Warehouse

    Hugelius, G.; Bockheim, James G.; Camill, P.; Elberling, B.; Grosse, G.; Harden, J.W.; Johnson, K.; Jorgenson, T.; Koven, C.D.; Kuhry, P.; Michaelson, G.; Mishra, U.; Palmtag, J.; Ping, C.-L.; O'Donnell, J.; Schirrmeister, L.; Schuur, E.A.G.; Sheng, Y.; Smith, L.C.; Strauss, J.; Yu, Z.

    2013-01-01

    High-latitude terrestrial ecosystems are key components in the global carbon cycle. The Northern Circumpolar Soil Carbon Database (NCSCD) was developed to quantify stocks of soil organic carbon (SOC) in the northern circumpolar permafrost region (a total area of 18.7 × 106 km2). The NCSCD is a geographical information system (GIS) data set that has been constructed using harmonized regional soil classification maps together with pedon data from the northern permafrost region. Previously, the NCSCD has been used to calculate SOC storage to the reference depths 0–30 cm and 0–100 cm (based on 1778 pedons). It has been shown that soils of the northern circumpolar permafrost region also contain significant quantities of SOC in the 100–300 cm depth range, but there has been no circumpolar compilation of pedon data to quantify this deeper SOC pool and there are no spatially distributed estimates of SOC storage below 100 cm depth in this region. Here we describe the synthesis of an updated pedon data set for SOC storage (kg C m-2) in deep soils of the northern circumpolar permafrost regions, with separate data sets for the 100–200 cm (524 pedons) and 200–300 cm (356 pedons) depth ranges. These pedons have been grouped into the North American and Eurasian sectors and the mean SOC storage for different soil taxa (subdivided into Gelisols including the sub-orders Histels, Turbels, Orthels, permafrost-free Histosols, and permafrost-free mineral soil orders) has been added to the updated NCSCDv2. The updated version of the data set is freely available online in different file formats and spatial resolutions that enable spatially explicit applications in GIS mapping and terrestrial ecosystem models. While this newly compiled data set adds to our knowledge of SOC in the 100–300 cm depth range, it also reveals that large uncertainties remain. Identified data gaps include spatial coverage of deep (> 100 cm) pedons in many regions as well as the spatial extent of areas

  5. Creating breakthroughs at 3M.

    PubMed

    von Hippel, E; Thomke, S; Sonnack, M

    1999-01-01

    Most senior managers want their product development teams to create break-throughs--new products that will allow their companies to grow rapidly and maintain high margins. But more often they get incremental improvements to existing products. That's partly because companies must compete in the short term. Searching for breakthroughs is expensive and time consuming; line extensions can help the bottom line immediately. In addition, developers simply don't know how to achieve breakthroughs, and there is usually no system in place to guide them. By the mid-1990s, the lack of such a system was a problem even for an innovative company like 3M. Then a project team in 3M's Medical-Surgical Markets Division became acquainted with a method for developing breakthrough products: the lead user process. The process is based on the fact that many commercially important products are initially thought of and even prototyped by "lead users"--companies, organizations, or individuals that are well ahead of market trends. Their needs are so far beyond those of the average user that lead users create innovations on their own that may later contribute to commercially attractive breakthroughs. The lead user process transforms the job of inventing breakthroughs into a systematic task of identifying lead users and learning from them. The authors explain the process and how the 3M project team successfully navigated through it. In the end, the team proposed three major new product lines and a change in the division's strategy that has led to the development of breakthrough products. And now several more divisions are using the process to break away from incrementalism.

  6. Genetics Home Reference: 3-M syndrome

    MedlinePlus

    ... Kuklik M, Zemkova D, Kozlowski K. 3-M syndrome in two sisters. J Paediatr Child Health. 2002 Aug;38(4):419-22. Citation on PubMed Temtamy SA, Aglan MS, Ashour AM, Ramzy MI, Hosny LA, Mostafa MI. 3-M syndrome: a report of three Egyptian cases with review ...

  7. SAGE III/Meteor - 3M

    NASA Technical Reports Server (NTRS)

    1999-01-01

    From left to right: Richard Rawls, Chip Holloway, and Art Hayhurst standing next to the Stratospheric Aerosol Gastropheric Experiment (SAGE)/Meteor - 3M flight instrument. Photographed in building 1250, 40 foot clean room.

  8. SAGE III/Meteor - 3M

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Back view of the SAGE III Bench Checkout Unit, Portable Image Generator (PIG) on tripod, and the Stratospheric Aerosol Gastropheric Experiment (SAGE)/Meteor - 3M flight instrument. Photographed in building 1250, 40 foot clean room.

  9. SAGE III/Meteor - 3M

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Full view of the SAGE III Bench Checkout Unit, Collimated Source Bench (CSB), Portable Image Generator (PIG) on tripod, and Stratospheric Aerosol Gastropheric Experiment (SAGE)/Meteor - 3M flight instrument. Photographed in building 1250, 40 foot clean room.

  10. In situ formation of oxygen vacancy in perovskite Sr0.95Ti0.8Nb0.1M0.1O3 (M = Mn, Cr) toward efficient carbon dioxide electrolysis

    PubMed Central

    Zhang, Jun; Xie, Kui; Wei, Haoshan; Qin, Qingqing; Qi, Wentao; Yang, Liming; Ruan, Cong; Wu, Yucheng

    2014-01-01

    In this work, redox-active Mn or Cr is introduced to the B site of redox stable perovskite Sr0.95Ti0.9Nb0.1O3.00 to create oxygen vacancies in situ after reduction for high-temperature CO2 electrolysis. Combined analysis using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric analysis confirms the change of the chemical formula from oxidized Sr0.95Ti0.9Nb0.1O3.00 to reduced Sr0.95Ti0.9Nb0.1O2.90 for the bare sample. By contrast, a significant concentration of oxygen vacancy is additionally formed in situ for Mn- or Cr-doped samples by reducing the oxidized Sr0.95Ti0.8Nb0.1M0.1O3.00 (M = Mn, Cr) to Sr0.95Ti0.8Nb0.1M0.1O2.85. The ionic conductivities of the Mn- and Cr-doped titanate improve by approximately 2 times higher than bare titanate in an oxidizing atmosphere and 3–6 times higher in a reducing atmosphere at intermediate temperatures. A remarkable chemical accommodation of CO2 molecules is achieved on the surface of the reduced and doped titanate, and the chemical desorption temperature reaches a common carbonate decomposition temperature. The electrical properties of the cathode materials are investigated and correlated with the electrochemical performance of the composite electrodes. Direct CO2 electrolysis at composite cathodes is investigated in solid-oxide electrolyzers. The electrode polarizations and current efficiencies are observed to be significantly improved with the Mn- or Cr-doped titanate cathodes. PMID:25403738

  11. Dinosaur extinction: closing the '3 m gap'.

    PubMed

    Lyson, Tyler R; Bercovici, Antoine; Chester, Stephen G B; Sargis, Eric J; Pearson, Dean; Joyce, Walter G

    2011-12-23

    Modern debate regarding the extinction of non-avian dinosaurs was ignited by the publication of the Cretaceous-Tertiary (K-T) asteroid impact theory and has seen 30 years of dispute over the position of the stratigraphically youngest in situ dinosaur. A zone devoid of dinosaur fossils reported from the last 3 m of the Upper Cretaceous, coined the '3 m gap', has helped drive controversy. Here, we report the discovery of the stratigraphically youngest in situ dinosaur specimen: a ceratopsian brow horn found in a poorly rooted, silty, mudstone floodplain deposit located no more than 13 cm below the palynologically defined boundary. The K-T boundary is identified using three criteria: (i) decrease in Cretaceous palynomorphs without subsequent recovery, (ii) the existence of a 'fern spike', and (iii) correlation to a nearby stratigraphic section where primary extraterrestrial impact markers are present (e.g. iridium anomaly, spherules, shocked quartz). The in situ specimen demonstrates that a gap devoid of non-avian dinosaur fossils does not exist and is inconsistent with the hypothesis that non-avian dinosaurs were extinct prior to the K-T boundary impact event.

  12. Efficient 3M PBS enhancing miniature projection optics

    NASA Astrophysics Data System (ADS)

    Yun, Zhisheng; Nevitt, Timothy; Willett, Stephen; Mortenson, Dave; Le, John; McDowell, Erin; Kent, Susan; Wong, Timothy; Beniot, Gilles J.; Ouderkirk, Andrew

    2016-09-01

    Over the past decade, 3M has developed a number of mobile projectors, with a goal towards providing the world's smallest, most efficient projection systems. Compact size and efficiency are required characteristics for projection systems used in mobile devices and more lately, in augmented reality systems. In this paper we summarize the main generations of 3M light engine optical designs. We present the optical architectures of four light engines, including the rationale behind the illumination designs and the projection systems. In particular, we describe various configurations relating to the 3M polarizing beam splitter (PBS) which is key to enhanced efficiency of the miniature projection systems.

  13. The 3M complex maintains microtubule and genome integrity

    PubMed Central

    Yan, Jun; Yan, Feng; Li, Zhijun; Sinnott, Becky; Cappell, Kathryn M.; Yu, Yanbao; Mo, Jinyao; Duncan, Joseph A.; Chen, Xian; Cormier-Daire, Valerie; Whitehurst, Angelique W.; Xiong, Yue

    2014-01-01

    SUMMARY CUL7, OBSL1, and CCDC8 genes are mutated in a mutually exclusive manner in 3M and other growth retardation syndromes. The mechanism underlying the function of the three 3M genes in development is not known. We found that OBSL1 and CCDC8 form a complex with CUL7 and regulate the level and centrosomal localization of CUL7, respectively. CUL7 depletion results in altered microtubule dynamics, prometaphase arrest, tetraploidy and mitotic cell death. These defects are recaptured in CUL7 mutated 3M cells and can be rescued by wild-type, but not 3M patients-derived CUL7 mutants. Depletion of either OBSL1 or CCDC8 results in similar defects and sensitizes cells to microtubule damage as loss of CUL7 function. Microtubule damage reduces the level of CCDC8 that is required for the centrosomal localization of CUL7. We propose that CUL7, OBSL1, and CCDC8 proteins form a 3M complex that functions in maintaining microtubule and genome integrity and normal development. PMID:24793695

  14. Strategic stories: how 3M is rewriting business planning.

    PubMed

    Shaw, G; Brown, R; Bromiley, P

    1998-01-01

    Virtually all business plans are written as a list of bullet points. Despite the skill or knowledge of their authors, these plans usually aren't anything more than lists of "good things to do." For example: Increase sales by 10%. Reduce distribution costs by 5%. Develop a synergistic vision for traditional products. Rarely do these lists reflect deep thought or inspire commitment. Worse, they don't specify critical relationships between the points, and they can't demonstrate how the goals will be achieved. 3M executive Gordon Shaw began looking for a more coherent and compelling way to present business plans. He found it in the form of strategic stories. Telling stories was already a habit of mind at 3M. Stories about the advent of Post-it Notes and the invention of masking tape help define 3M's identity. They're part of the way people at 3M explain themselves to their customers and to one another. Shaw and his coauthors examine how business plans can be transformed into strategic narratives. By painting a picture of the market, the competition, and the strategy needed to beat the competition, these narratives can fill in the spaces around the bullet points for those who will approve and those who will implement the strategy. When people can locate themselves in the story, their sense of commitment and involvement is enhanced. By conveying a powerful impression of the process of winning, narrative plans can mobilize an entire organization.

  15. 76 FR 70443 - Decision on Waiver Application From 3M

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    ...: Notice. SUMMARY: EPA conditionally granted the request from 3M for a waiver from testing tetrabromobisphenol A (CASRN 79-94-7). Regulations issued by EPA under section 4 of the Toxic Substances Control Act... application is submitted to EPA and is approved. EPA received such a request for a waiver from these...

  16. Deployment of a Pair of 3 M telescopes in Utah

    SciTech Connect

    Finnegan, G.; Adams, B.; Butler, K.; Cardoza, J.; Colin, P.; Hui, C. M.; Kieda, D.; Kirkwood, D.; Kress, D.; Kress, M.; LeBohec, S.; McGuire, C.; Newbold, M.; Nunez, P.; Pham, K.

    2008-12-24

    Two 3 m telescopes are being installed in Grantsville Utah. They are intended for the testing of various approaches to the implementation of intensity interferometry using Cherenkov Telescopes in large arrays as receivers as well as for the testing of novel technology cameras and electronics for ground based gamma-ray astronomy.

  17. Stephen Hawking bags big new 3m physics prize

    NASA Astrophysics Data System (ADS)

    Johnston, Hamish

    2013-01-01

    A massive 3m in prize money has gone to the British cosmologist Stephen Hawking for his work on black holes, quantum gravity and the early universe. The award is one of two "special fundamental physics prizes" from the Fundamental Physics Prize Foundation, which was set up earlier this year by the Russian physicist-turned-entrepreneur Yuri Milner.

  18. Testing of the 3M Company Composite Conductor

    SciTech Connect

    Stovall, John P; Rizy, D Tom; Kisner, Roger A

    2010-10-01

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum-Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors. The objective of this work is to accelerate the commercial acceptance by electric utilities of this new conductor design by testing four representative conductor classes in controlled conditions. A unique facility called the Powerline Conductor Accelerated Testing (PCAT) Facility was built at ORNL for testing overhead conductors. The PCAT has been uniquely designed for testing overhead bare transmission line conductors at high currents and temperatures after they have been installed and tensioned to the manufacturer's specifications. The ability to operate a transmission line conductor in this manner does not exist elsewhere in the United States. Four classes of ACCR cable designed by the 3M Company have been successfully test at ORNL small, medium, large and small/compact. Based on these and other manufacturer tests, the 3M Company has successfully introduced the ACCR into the commercial market and has completed over twenty installations for utility companies.

  19. Concerning neutral flux shielding in the U-3M torsatron

    SciTech Connect

    Dreval, N. B.

    2015-03-15

    The volume of the torsatron U-3M vacuum chamber is about 70 m{sup 3}, whereas the plasma volume is about 0.3 m{sup 3}. The large buffer volume of the chamber serves as a source of a substantial neutral flux into the U-3M plasma. A fraction of this flux falls onto the torsatron helical coils located in front of the plasma, due to which the dynamics of neutral influx into the plasma modifies. The shielding of the molecular flux from the buffer volume into the plasma is estimated using numerical calculations. Only about 10% of the incident flux reaches the plasma volume. Estimates show that about 20% of atoms escape beyond the helical coils without colliding with them. Under these conditions, the helical coils substantially affect the neutral flux. A discharge regime with a hot low-density plasma produced by a frame antenna is considered. The spatial distribution of the molecular density produced in this regime by the molecular flux from the chamber buffer volume after it has passed between the helical coils is calculated. The contributions of the fluxes emerging from the side and inner surfaces of the helical coils are considered. The calculations show that the shape of the spatial distribution of the molecular density differs substantially from the shape of the magnetic surfaces.

  20. Cost and Performance Report 3M Selective Separation Cartridges

    SciTech Connect

    Pickett, J.B.

    2000-12-19

    In the summer of 1998, the Department of Energy's Office of Environmental Management (EM-50) initiated a water treatment project through its Accelerated Site Technology Deployment (ASTD) program at the Savannah River Site (DOE-SR, 1999). The purpose of the ASTD project was to deploy new and innovative water treatment technologies - that offer significant improvements over existing baseline technologies - in the removal of cesium and strontium from contaminated water. One of the technologies selected by EM-50 was the Selective Separation Cartridge, based on an innovative membrane technology developed the 3M Co., St. Paul, MN (OST-2000).The Savannah River Site is committed to deploy this Selective Separation Cartridge technology at other appropriate locations. It may be appropriate for other Reactor Disassembly Basins, or in-situ groundwater remediation. The deployment of this technology will be considered strongly as opportunities present themselves. The primary lesson learned is to anticipate and plan to reduce the radiation dose from a Cs-137 removal system to As Low As Reasonably Achievable (ALARA) concept. 3M did not include any mitigating actions in their original design and fabrication, primarily because the system was completely constructed before WSRC became deeply involved with the 3M/EM-50 project.

  1. Hamline/3M Project: Liaison for Curricular Change

    NASA Astrophysics Data System (ADS)

    Rundquist, Andy

    2002-03-01

    This project was designed to catalyze curricular changes to better prepare students for the workplace. Industrial managers provided a list of 16 characteristics valued in the workplace: most were NOT related to science course content. The project formed 5 teams each including 3M professionals and students. Each team developed curricular changes in one of the 16 areas. Team goals were to improve skills in communication, data analysis, business/economics, team problem solving, and culture competency. Curricular changes realized include communication skill activities embodied in science courses and faculty communication teaching skill seminars, self learning tools in data analysis, statistics and model building, a new course developed with assistance from 3M personnel focussing on topics directly related to technological industries, high performance team problem solving training/coaching for faculty and workshops for students and faculty relative to importance of cultural competencies in the workplace, and a new course focusing on culture, team problem solving and conflict resolution in the technical workplace. Process for developing and content of curricular changes will be reported.

  2. Hamline/3M Corp. Project: Liason for Curricular Change*

    NASA Astrophysics Data System (ADS)

    Artz, Jerry L.

    2002-04-01

    This project was designed to catalyze curricular changes to better prepare students for the workplace. Industrial managers provided a list of 16 characteristics valued in the workplace; most were NOT related to science course content. The project formed 5 teams each including 3M professionals and students. Each team developed curricular changes in one of the 16 areas. Team goals were to improve skills in communication, data analysis, business/economics, team problem solving, and cultural competency. Curricular changes realized include communication skill activities embodied in science courses and faculty communication teaching skill seminars; self learning tools in data analysis, statistics and model building; a new course developed with assistance from 3M personnel focusing on topics directly related to technological industries; high performance team problem solving training/coaching for faculty; workshops for students and faculty relative to importance of cultural competencies in the workplace; and a new course focusing on culture, team problem solving and conflict resolution in the technical workplace. Process for developing and content of curricular changes will be reported. *Thanks to: NSF GOALI CHE-99010782

  3. 3M corporate incinerator environmental monitoring study and risk analysis

    SciTech Connect

    Stevens, J.B.; Elnabarawy, M.T.; Pilney, J.

    1998-12-31

    A one-year multi-media environmental monitoring study was performed around the 3M Cottage Grove Facility. Particulate metals from the 3M Corporate hazardous waste incinerator were the focus of the study. Two environmental media were of primary interest: area soil sampling was conducted to investigate the impact of past incinerator emissions on the environment, and ambient air monitoring was conducted to address current impacts. Over 180 soil samples were taken from both agricultural and forested land in the vicinity of the Facility. More than 25 chemical parameters were then quantified in the samples. The potential impacts of past emissions from the incinerator were assessed by comparing chemical concentrations from locations where incinerator impacts were expected to be greatest (based on air dispersion modeling) to chemical concentrations in matched samples from sites expected to be least impacted. The ambient air monitoring network consisted of six stations. Source-receptor modeling was used to determine the most likely contribution of the incinerator and six additional major area sources for the air monitoring (i.e. filter) data at each station. The model provided a best-fit analysis regarding the likely contributions of each source to the sample results. The results of these evaluations lead to the conclusion that the current emissions from this Facility do not present an unacceptable risk to human health.

  4. Testing of the 3M Company ACCR Conductor

    SciTech Connect

    Stovall, J.P.; RIzy, D.T.; Kisner, R.A.; Deve, H.E.

    2010-09-15

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum- Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors so the core has a lower density and higher conductivity. The objective of this work is to accelerate the commercial acceptance by electric utilities of these new conductor designs by testing four representative conductor classes in controlled conditions. Overhead transmission lines use bare aluminum conductor strands wrapped around a steel core strands to transmit electricity. The typical cable is referred to as aluminum-conductor steel-reinforced (ACSR). The outer strands are aluminum, chosen for its conductivity, low weight, and low cost. The center strand is of steel for the strength required to support the weight without stretching the aluminum due to its ductility. The power density of a transmission corridor has been directly increased by increasing the voltage level. Transmission voltages have increased from 115-kV to 765- kV over the past 80 years. In the United States, further increasing the voltage level is not feasible at this point in time, so in order to further increase the power density of a transmission corridor, conductor designs that increase the current carrying capability have been examined. One of the key limiting factors in the design of a transmission line is the conductor sag which determines the clearance of the conductor above ground or underlying structures needed for electrical safety. Increasing the current carrying capability of a conductor increases the joule heating in the conductor which increases the conductor sag. A conductor designed for high-temperature and lowsag operation requires an engineered modification of the conductor materials. To make an advanced cable, the 3M Company solution has been the development of a composite conductor consisting of Nextel ceramic fibers to replace the steel core and

  5. Observations of 3-m auroral irregularities during the ERRRIS campaigns

    NASA Astrophysics Data System (ADS)

    Sahr, J. D.; Farley, D. T.; Swartz, W. E.; Providakes, J. F.; Pfaff, R. F.

    1992-06-01

    In the late winter of 1988 and 1989, three NASA sounding rockets were flown through the auroral electrojet from ESRANGE (Sweden) as part of the E-region Rocket-Radar Instability Study (ERRRIS). Many ground-based instruments supported these flights, including the EISCAT, STARE, and CUPRI radars, as well as all-sky cameras, riometers, and magnetometers. In this paper the observations of the Cornell University Portable Radar Interferometer (CUPRI), which detected coherent backscatter from 3-m irregularities in the auroral E-region are summarized. Twenty hours of power spectra and interferometry data are available, and, during the 1989 campaign, three weeks of nearly continuous Range-Time-Intensity (RTI) and first moment data were recorded.

  6. Qualification Of Kapton Pretreatment Process Using 3M Scotch Weld 2216 For Solar Panel Application

    NASA Astrophysics Data System (ADS)

    Swamy, B. R.; Krishna, Priya G.; Venkatesh, K.; Nagendra, H. R.; Nanjundaswamy, T. S.

    2011-10-01

    Substrates for solar arrays intended to be used on satellite systems are generally made of aluminum honeycomb structure sandwiched with Carbon Fiber Reinforced Plastic (CFRP) face skin. Two mil thick KaptonTM sheets are co cured on one side of the aluminum /CFRP composite structure while realizing the substrate panels. This Kapton sheet would serve as an insulator over which solar cell blankets are bonded with suitable adhesive for the satellite solar panels. The satellite solar panels demands highest degree of quality and reliability and one of the prime factors in this regards is the bond strength of adhesive which is used to bond the solar cell blankets. Various methods of pretreatments of Kapton surface are in use for increasing the surface energy, which in turn results in improved bond strengths. These methods generally provide roughened surface of the Kapton which is achieved either by abrasive means like scrubbing the surface using fine silica chip, or plasma etching or alternatively by an additive process wherein suitable polyester, phenolic or other resins are coated on to the Kapton surface to achieve the desired results. For spacecraft solar panel applications at ISRO, polyester resin coating on to the Kapton surface was used as pretreatment prior to adhesive application. This process had provided adequate bond strengths between the solar cells and Kapton. Due to issues related to the supply of the polyester resin material from the vendor alternative methods of pretreatments were explored. In this paper, a novel process developed for Kapton pretreatment is described along with results of relevant qualifications for the satellite solar panel application. This newly developed pretreatment process for Kapton successfully adopts an epoxy based material 3M Scotch weld 2216 which is widely used in spacecraft electronic hardware.

  7. 3M's Model Rewards and Recognition Program Engages Employees and Drives Energy Savings Efforts

    SciTech Connect

    2010-06-11

    3M has implemented more than 1,900 employee-inspired projects that have realized a 22% improvement in energy efficiency and yielded $100 million in energy savings. This case study provides information about 3M's approach to energy efficiency.

  8. Optimizing Electric Motor Systems at a Corporate Campus Facility (3M)

    SciTech Connect

    2002-05-01

    3M conducted an in-house motor system study in 29 buildings at the 3M Center. The company evaluated approximately 1,000 electric motors and upgraded systems, resulting in reduced electricity use and cost savings of $77,554 per year.

  9. Phospholipase C-independent effects of 3M3FBS in murine colon

    PubMed Central

    Dwyer, Laura; Kim, Hyunjin; Koh, Byoung Ho; Koh, Sang Don

    2009-01-01

    The muscarinic receptor subtype M3 is coupled to Gq/11 proteins. Muscarinic receptor agonists such as carbachol stimulate these receptors that result in activation of phospholipase C (PLC) which hydrolyzes phosphatidylinositol 4,5-bisphosphate into diacylglycerol and Ins(1,4,5)P3. This pathway leads to excitation and smooth muscle contraction. In this study the PLC agonist, 2, 4, 6-trimethyl-N-(meta-3-trifluoromethyl-phenyl)-benezenesulfonamide (m-3M3FBS), was used to investigate whether direct PLC activation mimics carbachol-induced excitation. We examined the effects of m-3M3FBS and 2, 4, 6-trimethyl-N-(ortho-3-trifluoromethyl-phenyl)-benzenesulfonamide (o-3M3FBS), on murine colonic smooth muscle tissue and cells by performing conventional microelectrode recordings, isometric force measurements and patch clamp experiments. Application of m-3M3FBS decreased spontaneous contractility in murine colonic smooth muscle without affecting the resting membrane potential. Patch clamp studies revealed that delayed rectifier K+ channels were reversibly inhibited by m-3M3FBS and o-3M3FBS. The PLC inhibitor, 1-(6-((17b-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), did not prevent this inhibition by m-3M3FBS. Both m-3M3FBS and o-3M3FBS decreased two components of delayed rectifier K+ currents in the presence of tetraethylammonium chloride or 4-aminopyridine. Ca2+ currents were significantly suppressed by m-3M3FBS and o-3M3FBS with a simultaneous increase in intracellular Ca2+. Pretreatment with U73122 did not prevent the decrease in Ca2+ currents upon m-3M3FBS application. In conclusion, both m-3M3FBS and o-3M3FBS inhibit inward and outward currents via mechanisms independent of PLC acting in an antagonistic manner. In contrast, both compounds also caused an increase in [Ca2+]i in an agonistic manner. Therefore caution must be employed when interpreting their effects at the tissue and cellular level. PMID:19931239

  10. Phospholipase C-independent effects of 3M3FBS in murine colon.

    PubMed

    Dwyer, Laura; Kim, Hyun Jin; Koh, Byoung Ho; Koh, Sang Don

    2010-02-25

    The muscarinic receptor subtype M(3) is coupled to Gq/11 proteins. Muscarinic receptor agonists such as carbachol stimulate these receptors that result in activation of phospholipase C (PLC) which hydrolyzes phosphatidylinositol 4,5-bisphosphate into diacylglycerol and Ins(1,4,5)P(3). This pathway leads to excitation and smooth muscle contraction. In this study the PLC agonist, 2, 4, 6-trimethyl-N-(meta-3-trifluoromethyl-phenyl)-benezenesulfonamide (m-3M3FBS), was used to investigate whether direct PLC activation mimics carbachol-induced excitation. We examined the effects of m-3M3FBS and 2, 4, 6-trimethyl-N-(ortho-3-trifluoromethyl-phenyl)-benzenesulfonamide (o-3M3FBS), on murine colonic smooth muscle tissue and cells by performing conventional microelectrode recordings, isometric force measurements and patch clamp experiments. Application of m-3M3FBS decreased spontaneous contractility in murine colonic smooth muscle without affecting the resting membrane potential. Patch clamp studies revealed that delayed rectifier K(+) channels were reversibly inhibited by m-3M3FBS and o-3M3FBS. The PLC inhibitor, 1-(6-((17b-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), did not prevent this inhibition by m-3M3FBS. Both m-3M3FBS and o-3M3FBS decreased two components of delayed rectifier K(+) currents in the presence of tetraethylammonium chloride or 4-aminopyridine. Ca(2+) currents were significantly suppressed by m-3M3FBS and o-3M3FBS with a simultaneous increase in intracellular Ca(2+). Pretreatment with U73122 did not prevent the decrease in Ca(2+) currents upon m-3M3FBS application. In conclusion, both m-3M3FBS and o-3M3FBS inhibit inward and outward currents via mechanisms independent of PLC acting in an antagonistic manner. In contrast, both compounds also caused an increase in [Ca(2+)](i) in an agonistic manner. Therefore caution must be employed when interpreting their effects at the tissue and cellular level.

  11. 101. JOB NO. 1347F, SHEET 3M, 1927, ASSEMBLY BUILDING; FORD ...

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

    101. JOB NO. 1347-F, SHEET 3M, 1927, ASSEMBLY BUILDING; FORD MOTOR COMPANY; ONE-EIGHTH SCALE OF OFFICES - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  12. 115. JOB NO. 1347K, SHEET 3M, 1929/1930, FORD MOTOR COMPANY; ...

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

    115. JOB NO. 1347-K, SHEET 3M, 1929/1930, FORD MOTOR COMPANY; BOILER HOUSE ASSEMBLY PLANT; BOILER SETTING - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  13. The LIULIN-3M Radiometer for Measuring Particle Doses in Space and on Aircraft

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Stauffer, C. A.; Dachev, T. P.; Brucker, G. J.; Tomov, B. T.; Dimitrov, P. G.

    1999-01-01

    This paper reports on the development of a compact radiation monitor/dosimeter, the LIULIN-3M, and on extended measurements conducted on the ground and on commercial aircraft on domestic and international flights.

  14. Measurements of Radiation Exposure on Commercial Aircraft with the LIULIN-3M Instrument

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Stauffer, C. A.; Dachev, T. P.; Brucker, G. J.; Tomov, B. T.; Dimitrov, P. G.

    1998-01-01

    This paper reports on the development of a compact radiation monitor/dosimeter, the LIULIN-3M, and on extended measurements conducted on the ground and on commercial aircraft on domestic and international flights.

  15. The LIULIN-3M Radiometer for Measuring Particle Doses in Space and on Aircraft

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Stauffer, C. A.; Dachev, T. P.; Tomov, B. T.; Dimitrov, P. G.; Brucker, G. J.; Obenschain, Art (Technical Monitor)

    2002-01-01

    This paper reports on the development of a compact radiation monitor/dosimeter, the LIULIN-3M, and on extended measurements conducted on the ground and on commercial aircraft on domestic and international flights.

  16. Manipulation of electronic structure via alteration of local orbital environment in [(SrIrO3)m,(SrTi O3)] (m =1 ,2 ,and ∞ ) superlattices

    NASA Astrophysics Data System (ADS)

    Kim, So Yeun; Kim, Choong H.; Sandilands, L. J.; Sohn, C. H.; Matsuno, J.; Takagi, H.; Kim, K. W.; Lee, Y. S.; Moon, S. J.; Noh, T. W.

    2016-12-01

    We investigated the electronic structure of [(SrIrO3)m,(SrTi O3)] (m =1 ,2 ,and ∞ ) superlattice (SL) thin films with optical spectroscopy and first principles calculations. Our optical results confirmed the existence of the Jeff= 1 /2 states in SL samples, similar to the bulk Ruddlesden-Popper series S rn+1I rnO3 n +1 iridates. Apart from this similarity, in the SL samples, we observed red shifts of the characteristic optical excitations in the Jeff= 1 /2 state and an enhancement of the low-energy spectral weight, which implies a reduction in the effective electron correlation for bands near the Fermi energy. The density functional theory plus Coulomb interactions (DFT +U ) calculations suggested that the SrTi O3 layer intervened between SrIr O3 layers in the SLs activated additional hopping channels between the Ir ions, thus increasing the bandwidth and reducing the effective strength of the correlations. This paper demonstrates that fabrication of iridium-based heterostructures can be used to finely tune electronic structures via alteration of their local orbital environments.

  17. 3M Tecra Listeria Visual Immunoassay: AOAC Official Methods 995.22 and 2002.09.

    PubMed

    Benesh, Deann L; Crowley, Erin S; Bird, Patrick M

    2013-01-01

    A validation study of the 3M Tecra Listeria Visual Immunoassay (VIA; 3M Food Safety, St. Paul, MN) was conducted at Q Laboratories, Inc., Cincinnati, OH. The 3M Tecra Listeria VIA method was compared to the Health Canada MFHPB-30 reference method for the analysis of five ready-to-eat (RTE) meats: deli turkey, hot dogs, liver pate, raw fermented sausage, and deli ham, and on a stainless steel environmental surface. Twenty replicates of each of the five food matrixes were analyzed at a low and a high inoculum level. The low-level test portions were inoculated with 0.2-2 CFU/25 g, and the high-level test portions with 2-5 CFU/25 g. In addition, 20 replicates of one environmental surface were analyzed at a low and a high inoculum level. The low-level sampling area was inoculated with 0.2-2 CFU/5 cm2, and the high-level area with 2-5 CFU/5 cm2. Five control replicates were also analyzed at 0 CFU/25 g (uninoculated) for the foods and at 0 CFU/5 cm2 for the environmental sampling area. There was no significant difference in the number of positives detected by the 3M Tecra Listeria VIA and the Health Canada MFHPB-30 reference method for four of the RTE meats and the stainless steel environmental surface analyzed in this study. For the raw, fermented sausage, there was a significant difference in the number of positives detected for the high inoculum level by the 3M Tecra Listeria VIA and the Health Canada MFHPB-30 reference method, with the 3M Tecra Listeria VIA method detecting more positives.

  18. Flux growth of MBO3 (M=Fe, Ga, In, Sc, Lu) single crystals

    NASA Astrophysics Data System (ADS)

    Ovchinnikov, S. G.; Rudenko, V. V.

    2016-12-01

    The temperatures for saturation of the MBO3 (M=Fe, Ga, In, Sc, Lu) compounds in the M2O3-B2O3- (70 PbO-30 PbF2, wt%) solvents are determined. The growth rates of FeBO3 and GaBO3 crystal faces as functions of the flux supercooling are obtained. It is demonstrated that the bulk FeBO3 and GaBO3 crystals can be grown in a narrow flux supercooling range using a controlled seeding technique. The MBO3 (M=In, Sc, Lu) crystals in the form of (111) plates are synthesized by spontaneous crystallization.

  19. Model experience in the Langley 0.3-m transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Lawing, P. L.; Kilgore, R. A.

    1981-01-01

    The model building, development, and testing experience gained during 8 years of operation of the 0.3-m Transonic Cryogenic Tunnel (TCT) is summarized. The summary is divided into four portions: (1) models tested in the 0.3-m TCT's original octagonal test section; (2) models tested in the present two dimensional test section; (3) models tested as a part of tunnel calibration and the development of advanced technology airfoils; and (4) development of a new way to construct two dimensional airfoil models. Design requirements imposed on the models by high Reynolds number testing at cryogenic temperatures are reviewed.

  20. CDKN3 mRNA as a Biomarker for Survival and Therapeutic Target in Cervical Cancer

    PubMed Central

    Barrón, Eira Valeria; Roman-Bassaure, Edgar; Sánchez-Sandoval, Ana Laura; Espinosa, Ana María; Guardado-Estrada, Mariano; Medina, Ingrid; Juárez, Eligia; Alfaro, Ana; Bermúdez, Miriam; Zamora, Rubén; García-Ruiz, Carlos; Gomora, Juan Carlos; Kofman, Susana; Pérez-Armendariz, E. Martha; Berumen, Jaime

    2015-01-01

    The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10−6, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5–10, p = 3.3 x 10−6, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC. PMID:26372210

  1. Attenuation of kindling-induced decreases in NT-3 mRNA by thyroid hormone depletion.

    PubMed

    Kim, S Y; Smith, M A; Post, R M; Rosen, J B

    1998-02-01

    The expression of neurotrophins is altered by amygdala kindled seizures. Because thyroid hormone can regulate the transcription of neurotrophins, we asked whether thyroid hormone regulates neurotrophin mRNA expression following amygdala kindling. Rats with electrodes implanted in the basolateral nucleus of the amygdala were either depleted of thyroid hormone or given excess thyroid hormone. The rats were then kindled daily until they had one generalized seizure. The brains were removed 4 h after the seizure and processed for in situ hybridization of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) mRNAs. In non-kindled rats, thyroid hormone depletion increased the levels of BDNF mRNA in the paraventricular nucleus of the hypothalamus and the pituitary gland. NGF and NT-3 mRNA expression was not altered. In addition, thyroid hormone manipulations had no effect on kindling or on kindling-induced BDNF and NGF mRNA. However, the kindling-induced decrease in NT-3 mRNA expression in the dentate gyrus granule cell layer was significantly attenuated by thyroid hormone depletion. These effects were reversed by thyroid hormone replacement. The results indicate that thyroid hormone plays a modulatory role in the seizure-induced changes of NT-3 mRNA expression found in the dentate gyrus.

  2. CDKN3 mRNA as a Biomarker for Survival and Therapeutic Target in Cervical Cancer.

    PubMed

    Barrón, Eira Valeria; Roman-Bassaure, Edgar; Sánchez-Sandoval, Ana Laura; Espinosa, Ana María; Guardado-Estrada, Mariano; Medina, Ingrid; Juárez, Eligia; Alfaro, Ana; Bermúdez, Miriam; Zamora, Rubén; García-Ruiz, Carlos; Gomora, Juan Carlos; Kofman, Susana; Pérez-Armendariz, E Martha; Berumen, Jaime

    2015-01-01

    The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10-6, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5-10, p = 3.3 x 10-6, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC.

  3. A DS106 Thing Happened on the Way to the 3M Tech Forum

    ERIC Educational Resources Information Center

    Lockridge, Rochelle; Levine, Alan; Funes, Mariana

    2014-01-01

    This case study illustrates how DS106, a computer science course in Digital Storytelling from the University of Mary Washington (UMW) and accessible as an open course on the web, is being explored in a corporate environment at 3M, an American multinational corporation based in St. Paul, Minnesota, to build community, collaboration, and more…

  4. Shear in the zonal drifts of 3 m irregularities inside spread F plumes observed over Sanya

    NASA Astrophysics Data System (ADS)

    Li, Guozhu; Ning, Baiqi; Liu, Libo; Abdu, M. A.; Wan, Weixing; Hu, Lianhuan

    2015-09-01

    Incoherent scatter radars near magnetic equator regularly measured a vertical shear in zonal drifts of the evening background plasma, with westward drifts below the equatorial F region peak and eastward drifts above. We report here observations of a clear shear structure in the zonal drifts of 3 m irregularities inside spread F (SF) backscatter plumes measured with a 47.5 MHz coherent scatter radar operated at a low-latitude site Sanya (18.4°N, 109.6°E; dip latitude 12.8°N). The radar interferometry analysis on the zonal drifts of the 3 m irregularities yields results consistent with that estimated from the irregularity echo Doppler velocity measurements with multiple beams. It is shown that the SF 3 m irregularities move westward at the lowest altitudes, while at higher altitudes in the same SF plume structure, the 3 m irregularities drift eastward. One interesting point is that the vertical shear of zonal drifts was centered at ~300 km altitude over Sanya, which maps to an apex altitude of ~650 km at magnetic equator and is thus apparently higher than the apex altitudes 250-450 km where the zonal velocity shear has usually been observed. Analysis of the observations suggests that while the possibility of local generation of the shear flow of the irregularities can exist, the possibility of a plasma vortex appearing at relative high altitudes causing the zonal drift shear of F region 3 m irregularities measured over Sanya cannot be totally ruled out.

  5. Stimulation of high-frequency breakdown of gas in Uragan-3M torsatron by runaway electrons

    NASA Astrophysics Data System (ADS)

    Tarasov, I. K.; Tarasov, M. I.; Sitnikov, D. A.; Pashnev, V. K.; Lytova, M. A.

    2016-01-01

    In experiments on confinement and heating of plasma in the Uragan-3M torsatron, the method of high-frequency breakdown of the working gas is used. In these experiments, in conditions of a relatively stable magnetic field, the rf power supplied to the setup chamber has a frequency close to the ion-cyclotron frequency. Such a method of gas breakdown is not always sufficiently reliable. In our experiments, preliminary ionization of the working gas by the run-away electron beam is used for stabilizing the breakdown. This work contains the results of experiments on enhancement of the runaway electron beam and on the interaction of the runaway electron beam in the Uragan-3M torsatron with the HF electromagnetic pump field. This enables us to formulate a number of recommendations for using spontaneously formed beams of accelerated particles for stimulating the rf breakdown. Our results confirm the possibility of gas breakdown by runaway electrons.

  6. Florida hospital saves 5.3 M dollars by adopting principles of lean manufacturing.

    PubMed

    2005-01-01

    Florida hospital saves 5.3M dollars by adopting principles of lean manufacturing. Surgery cancellations have been slashed from 13% of cases to less than 3%, while emergency department admissions have increased by 20%. Those are just two of the results of a quality improvement project at Lee Memorial Health System in Fort Myers, FL, that focused on using the principles of lean manufacturing to improve patient flow in the five-hospital system

  7. A 3 m. y. record of Pliocene-Pleistocene loess in interior Alaska

    SciTech Connect

    Westgate, J.A.; Stemper, B.A. ); Pewe, T.L. )

    1990-09-01

    Many distal tephra beds exist in the thick, fossiliferous loess deposits near Fairbanks interior Alaska. Isothermal plateau fission-track ages, determined on glass shards from tephra beds, in conjunction with tephrostratigraphic and magnetostratigraphic techniques, indicate that loess deposition began in the late Pliocene-an antiquity previously unsuspected. Hence, there is the opportunity now to reconstruct a detailed, well-dated record of environmental changes in interior Alaska during the past 3 m.y.

  8. Ultra Barrier Topsheet Film for Flexible Photovoltaics with 3M Company

    SciTech Connect

    Funkenbusch, Arnie; Ruth, Charles

    2014-12-30

    In this DOE sponsored program, 3M achieved the critical UBT features to enable durable flexible high efficiency modules to be produced by a range of customers who have now certified the 3M UBT and are actively developing said flexible modules. The specific objectives and accomplishments of the work under this program were; Scale-up the current Generation-1 UBT from 12” width, as made on 3M’s pilot line, to 1+meter width full-scale manufacturing, while maintaining baseline performance metrics (see table below); This objective was fully met; Validate service life of Generation-1 UBT for the 25+ year lifetime demanded by the photovoltaic market; Aggressive testing revealed potential failure modes in the Gen 1 UBT. Deficiencies were identified and corrective action taken in the Gen 2 UBT; Develop a Generation-2 UBT on the pilot line, targeting improved performance relative to baseline, including higher %T (percent transmission), lower water vapor transmission rate (WVTR) with targets based on what the technology needs for 25 year lifetime, proven lifetime of 25 years in solar module construction in the field, and lower cost; Testing of UBT Gen 2 under a wide range of conditions presented in this report failed to reveal any failure mode. Therefore UBT Gen 2 is known to be highly durable. 3M will continue to test towards statistically validating a 25 year lifetime under 3M funding; Transfer Generation-2 UBT from the pilot line to the full-scale manufacturing line within three years; and This objective was fully met.

  9. Fundamental experiments of radio astronomy by the paraboloidal antenna of 3.3 m diameter.

    NASA Astrophysics Data System (ADS)

    Sato, K.; Kuji, S.; Hara, T.; Fujishita, M.; Horiai, K.; Iwadate, K.; Sato, K.; Tsubokawa, T.; Tamura, Y.; Takano, S.; Tsuruta, S.; Asari, K.

    The 3.3 m diameter paraboloidal antenna was moved at early 1985 for fundamental experiments of radio astronomy at the International Latitude Observatory of Mizusawa. The antenna was originally manufactured for the telecomunication experiments at 4 GHz. The authors fitted up a new feed horn of 8 GHz-band for their experiments. The driving system was renewed as suitable for astronomical use by using DC servomotors, optical encoders and a micro-computer.

  10. Analysis of the Cyclotron Facility Calibration and Aircraft Results Obtained by LIULIN-3M Instrument

    NASA Technical Reports Server (NTRS)

    Dachev, T. P.; Stassinopoulos, E. G.; Tomov, B. T.; Dimitrov, P. G.; Matviichuk, Y. N.; Shurshakov, V. A.; Petrov, V. M.

    1998-01-01

    The LIULIN-3M instrument is a further development of the LIULIN dosimeter-radiometer, which has been used on the NffR space station in the 1988-1994 time period, The LIULIN-3M is designed for continuous monitoring of the radiation environment during the BION-12 satellite flight in 1999. A semiconductor detector with 1 mm thickness and 1 cm(exp 2) area is used in the instrument. Pulse high analysis technique is used for measurement of the energy losses in the detector. The final data sets from the instrument are the flux and the dose rate for the exposition time and 256 channels of LET spectra if a non-nal coincidence of the particles to the detector is considered. The LIULIN-3M instrument was calibrated by proton fluxes with different energies at the Indiana University Cyclotron Facility in June 1997 and was used for space radiation measurements during commercial aircraft flights. Obtained calibration and flight results are analyzed in the paper.

  11. Validation of the 3M molecular detection system for the detection of listeria in meat, seafood, dairy, and retail environments.

    PubMed

    Fortes, Esther D; David, John; Koeritzer, Bob; Wiedmann, Martin

    2013-05-01

    There is a continued need to develop improved rapid methods for detection of foodborne pathogens. The aim of this project was to evaluate the 3M Molecular Detection System (3M MDS), which uses isothermal DNA amplification, and the 3M Molecular Detection Assay Listeria using environmental samples obtained from retail delicatessens and meat, seafood, and dairy processing plants. Environmental sponge samples were tested for Listeria with the 3M MDS after 22 and 48 h of enrichment in 3M Modified Listeria Recovery Broth (3M mLRB); enrichments were also used for cultural detection of Listeria spp. Among 391 samples tested for Listeria, 74 were positive by both the 3M MDS and the cultural method, 310 were negative by both methods, 2 were positive by the 3M MDS and negative by the cultural method, and one sample was negative by the 3M MDS and positive by the cultural method. Four samples were removed from the sample set, prior to statistical analyses, due to potential cross-contamination during testing. Listeria isolates from positive samples represented L. monocytogenes, L. innocua, L. welshimeri, and L. seeligeri. Overall, the 3M MDS and culture-based detection after enrichment in 3M mLRB did not differ significantly (P < 0.05) with regard to the number of positive samples, when chi-square analyses were performed for (i) number of positive samples after 22 h, (ii) number of positive samples after 48 h, and (iii) number of positive samples after 22 and/or 48 h of enrichment in 3M mLRB. Among 288 sampling sites that were tested with duplicate sponges, 67 each tested positive with the 3M MDS and the traditional U.S. Food and Drug Administration Bacteriological Analytical Manual method, further supporting that the 3M MDS performs equivalently to traditional methods when used with environmental sponge samples.

  12. The holistic 3M modality of drug delivery nanosystems for cancer therapy

    NASA Astrophysics Data System (ADS)

    Sun, Jin; Luo, Cong; Wang, Yongjun; He, Zhonggui

    2013-01-01

    Cancer has become the leading cause of human death worldwide. There are many challenges in the treatment of cancer and the rapidly developing area of nanotechnology has shown great potential to open a new era in cancer therapy. This article, rather than being exhaustive, focuses on the striking progress in the drug delivery nanosystems (DDNS) for cancer therapy and selects typical examples to point out the emerging mode of action of DDNS from our perspective. Among the outstanding advances in DDNS for cancer therapy is the development of ``multicomponent delivery systems'', ``multifunctional nanocarriers'' and ``multistage delivery systems''. However, these represent only one aspect of DDNS research. In addition, nature is the best teacher and natural evolution pressure has meant that virions conform to the ``multitarget, multistage and multicomponent'' (3M) mode of action. Amazingly, traditional Chinese medicine (TCM), used for over 4000 years in China, also displays the same mode of action. Integrating the previous notable progress in nanoparticle technology, learned from the building mode of natural virions and the action concept of TCM, we propose an integrity-based 3M mode DDNS for cancer therapy: multitarget, multistage and multicomponent, which are not fragmented parts but an interconnected integrity. Based on the physiological multitarget and the pharmacokinetic multistage, multicomponent DDNS are rationally designed, where different components with individual specific functions act in a synergistic manner against each target at each disposition stage to maximize the targeted delivery effectiveness. In this article, we introduce each component of 3M DDNS in detail and describe some typical cases to realize the tumor-homing purposes.

  13. Unique Roll-Off Roof for Housing 1.3 m Telescope at Devasthal, Nainital

    NASA Astrophysics Data System (ADS)

    Bangia, Tarun

    2016-05-01

    Aryabhatta Research Institute of Observational Sciences (ARIES) had set up a 1.3 m telescope at Devasthal, Nainital, India in the year 2010. Country's largest roll-off roof was indigenously designed, fabricated and installed on top of a building (17 × 8 m) for housing 1.3 m telescope. Telescope was supplied by M/s DFM Engineering Inc., USA to ARIES and was installed in the building with unique roll-off roof to protect it from external environment. Roll-off roof was designed and fabricated considering various parameters and available manpower and resources at ARIES. This paper presents mechanical development work, simple but distinct design approach and innovative selection of materials to economically manufacture roll-off roof of large size (8 × 8 × 4 m) at hilly remote site of Devasthal situated in Central Himalayan region. All operations in the roof viz. opening of shutters and rolling of roof were motorized to facilitate observers during night observations.

  14. Differential targeting of VDAC3 mRNA isoforms influences mitochondria morphology.

    PubMed

    Michaud, Morgane; Ubrig, Elodie; Filleur, Sophie; Erhardt, Mathieu; Ephritikhine, Geneviève; Maréchal-Drouard, Laurence; Duchêne, Anne-Marie

    2014-06-17

    Intracellular targeting of mRNAs has recently emerged as a prevalent mechanism to control protein localization. For mitochondria, a cotranslational model of protein import is now proposed in parallel to the conventional posttranslational model, and mitochondrial targeting of mRNAs has been demonstrated in various organisms. Voltage-dependent anion channels (VDACs) are the most abundant proteins in the outer mitochondrial membrane and the major transport pathway for numerous metabolites. Four nucleus-encoded VDACs have been identified in Arabidopsis thaliana. Alternative cleavage and polyadenylation generate two VDAC3 mRNA isoforms differing by their 3' UTR. By using quantitative RT-PCR and in vivo mRNA visualization approaches, the two mRNA variants were shown differentially associated with mitochondria. The longest mRNA presents a 3' extension named alternative UTR (aUTR) that is necessary and sufficient to target VDAC3 mRNA to the mitochondrial surface. Moreover, aUTR is sufficient for the mitochondrial targeting of a reporter transcript, and can be used as a tool to target an unrelated mRNA to the mitochondrial surface. Finally, VDAC3-aUTR mRNA variant impacts mitochondria morphology and size, demonstrating the role of mRNA targeting in mitochondria biogenesis.

  15. Finishing of display glass for mobile electronics using 3M Trizact diamond tile abrasive pads

    NASA Astrophysics Data System (ADS)

    Zheng, Lianbin; Fletcher, Tim; Na, Tee Koon; Sventek, Bruce; Romero, Vince; Lugg, Paul S.; Kim, Don

    2010-10-01

    This paper will describe a new method being used during the finishing of glass displays for mobile electronics including mobile hand held devices and notebook computers. The new method consists of using 3M TrizactTM Diamond Tile Abrasive Pads. TrizactTM Diamond Tile is a structured fixed abrasive grinding technology developed by 3M Company. The TrizactTM Diamond Tile structured abrasive pad consists of an organic (polymeric binder) - inorganic (abrasive mineral, i.e., diamond) composite that is used with a water-based coolant. TrizactTM Diamond Tile technology can be applied in both double and single side grinding applications. A unique advantage of TrizactTM Diamond Tile technology is the combination of high stock removal and low sub-surface damage. Grinding results will be presented for both 9 micron and 20 micron grades of TrizactTM Diamond Tile abrasive pads used to finish several common display glasses including Corning GorillaTM glass and Soda Lime glass.

  16. [11'-Deoxyverticillin A induces caspase-dependent cell apoptosis in PC3M cells].

    PubMed

    Shi, Yingdi; Zhang, Yingqiu; Ni, Yangxiao; Shi, Guoli; Yang, Huaiyi

    2012-01-01

    Recent years, the incidence and mortality of prostate cancer have increased dramatically in China. At earlier stages, most diagnosed prostate cancers are responsive to androgen depletion treatment, yet, nearly all patients will eventually progress to metastatic androgen-independent prostate cancer (AIPC), which still has no effective therapeutic method or drug to deal with. 11'-Deoxyverticillin A (C42) belongs to the family of epipolythiodioxopiperazines (ETPs), an interesting class of fungal toxins that inhibit farnesyl transferase. Compounds holding such a property have been explored as putative anticancer agents. In this study, using PC3M cells, an AIPC cell line, we investigated the effect of the compound on apoptosis and explored the underlying mechanism. It revealed that C42 markedly enhanced the activity of caspase-3/7 and increased the accumulation of the cleaved PARP, all of which are the markers of apoptosis. It also revealed that C42 either decreased cell viability or inhibited the growth of PC3M cells. Moreover, we observed that the loss of cell viability and cell growth inhibition induced by C42 were both time- and dosage dependent. Taken together, we indicated that C42 can induce caspase-dependent apoptosis in AIPC cells, and the results presented here will broaden our knowledge about the molecular mechanisms by which C42 exerts its anticancer activity, and future work in this direction may provide valuable information in the development of these compounds into effective cancer therapeutic strategies against androgen-independent prostate cancer.

  17. 29 CFR 516.27 - “Board, lodging, or other facilities” under section 3(m) of the Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false âBoard, lodging, or other facilitiesâ under section 3(m) of...” under section 3(m) of the Act. (a) In addition to keeping other records required by this part, an... these terms are used in sec. 3(m) of the Act) furnished to them by the employer or by an...

  18. 29 CFR 516.27 - “Board, lodging, or other facilities” under section 3(m) of the Act.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false âBoard, lodging, or other facilitiesâ under section 3(m) of...” under section 3(m) of the Act. (a) In addition to keeping other records required by this part, an... these terms are used in sec. 3(m) of the Act) furnished to them by the employer or by an...

  19. Test of P3M-1 nacelle in Full-Scale Tunnel (FST)

    NASA Technical Reports Server (NTRS)

    1931-01-01

    Test of P3M-1 nacelle in Full-Scale Tunnel (FST). The NACA conducted drag tests on P3M-1 nacelle in 1931 which were presented in a special report to the Navy. Smith DeFrance described this work in the report's introduction: 'Tests were conducted in the full-scale wind tunnel on a five to four geared Pratt and Whitney Wasp engine mounted in a P3M-1 nacelle. In order to simulate the flight conditions the nacelle was assembled on a 15-foot span of wing from the same airplane. The purpose of the tests was to improve the cooling of the engine and to reduce the drag of the nacelle combination. Thermocouples were installed at various points on the cylinders and temperature readings were obtained from these by the power plants division. These results will be reported in a memorandum by that division. The drag results, which are covered by this memorandum, were obtained with the original nacelle condition as received from the Navy with the tail of the nacelle modified, with the nose section of the nacelle modified, with a Curtiss anti-drag ring attached to the engine, with a Type G ring developed by the N.A.C.A., and with a Type D cowling which was also developed by the N.A.C.A.' (p. 1) This picture shows the engine with a Curtiss anti-drag ring attached. The NACA tested several different modifications and cowlings as noted above. The Navy did not want to make any major structural alterations to the original wing and nacelle installation. Thus, the NACA did not conduct a full investigation of the aerodynamics of this particular configuration. DeFrance concludes his report with this note: 'in view of the limitations of the test, the drag data for the combinations tested may be summarized, and considering the necessity of temperature control and accessibility to the engine it is apparent that the best combination tested was with the large nose piece, the Curtiss anti-drag ring, and the modified tail section.'

  20. Pressure- and Temperature-Sensitive Paint at 0.3-m Transonic Cryogenic Tunnel

    NASA Technical Reports Server (NTRS)

    Watkins, A. Neal; Leighty, Bradley D.; Lipford, William E.; Goodman, Kyle Z.

    2015-01-01

    Recently both Pressure- and Temperature-Sensitive Paint experiments were conducted at cryogenic conditions in the 0.3-m Transonic Cryogenic Tunnel at NASA Langley Research Center. This represented a re-introduction of the techniques to the facility after more than a decade, and provided a means to upgrade the measurements using newer technology as well as demonstrate that the techniques were still viable in the facility. Temperature-Sensitive Paint was employed on a laminar airfoil for transition detection and Pressure-Sensitive Paint was employed on a supercritical airfoil. This report will detail the techniques and their unique challenges that need to be overcome in cryogenic environments. In addition, several optimization strategies will also be discussed.

  1. The refurbished 1.3-m Robotically Controlled Telescope at Kitt Peak

    NASA Astrophysics Data System (ADS)

    Gelderman, R.; Guinan, E.; Howell, S.; Mattox, J. R.; McGruder, C. H.; Walter, D. K.; Davis, D. R.; Everett, M.

    2003-05-01

    In 1999, the National Optical Astronomy Observatories (NOAO) announced the opportunity to "assume responsibility for operation of the Kitt Peak 1.3-m telescope." A group of astronomers/educators from institutions across the USA successfully proposed to refurbish and automate the observatory and operate it as the Robotically Controlled Telescope (RCT). The RCT Consortium has been established between Francis Marion University, the Planetary Science Institute, South Carolina State University, Villanova University, and Western Kentucky University to oversee the refurbishment and automation, and operate the telescope to successfully achieve its research and education goals. The RCT was commissioned in 1964 as the Remotely Controlled Telescope and utilized that epoch's computing and communication technology to provide unattended operation from NOAO headquarters in Tucson, about 90 km distant. The original incarnation of the RCT allowed astronomers to gain experience in the remote operation of observatories in order to both develop techniques for operating space-based telescopes and to increase the productivity of ground-based telescopes (Maran 1967 Science 158, 867). While these tests worked as well as could be expected given the technology of the time, the telescope and observatory were refitted in 1969 for classical, attended operations. The second life of the 1.3-m was as a heavily subscribed KPNO visitor facility, first with photoelectric photometers and later as an important testbed for the newest infrared instrumentation. In 1996 the telescope was removed from the list of available KPNO facilities and stood idle until the RCT Consortium hired EOS Technologies, Inc. to refurbish and automate the observatory. In winter 2003 most of the observatory systems have been refurbished and the commissioning has begun. Refurbishment of the RCT has been made possible by NASA grant NAG58762.

  2. Experience and Challenges in Implementing Stratospheric Aerosol Gas Experiment on Meteor-3M Platform

    NASA Technical Reports Server (NTRS)

    Habib, Shahid; Newsom, Jerry; Rawls, Richard

    2001-01-01

    Implementation of Stratospheric Aerosol Gas Experiment (SAGE) is a joint science mission between the Rosavioskosmos, also called Russian Aviation and Space Agency (RASA) and the National Aeronautics and Space Administration (NASA). Under the global collaboration agreement established by President Clinton and Yeltsin in 1995 between the United States and Russia, space was one of the major areas identified for joint scientific collaboration. There were several collaborative projects identified under space, earth, human exploration of space and aeronautics. SAGE was one of the key Earth Science instruments selected common to both countries' interests in ozone research. SAGE has a long space heritage, and four earlier versions of this instrument have flown in space for the last 15-year period. It has provided a vital ozone and aerosol data in the mid latitudes and has contributed in the overall ozone depletion research. SAGE II, the fourth instrument has been flying in space on NASA's Earth Radiation Budget Satellite (ERBS) for the last 14 years. Ball Aerospace built the instrument under Langley Research Center's (LaRC) management. SAGE III for Russian Meteor-3M mission is a third generation design with more spectral bands, elaborate data gathering and storage and intelligent terrestrial software. The Russian collaboration required a complete integration of SAGE III on the Russian Meteor-3M satellite and a launch on a Zenit-2 launch vehicle manufactured in Ukraine. The whole complex is scheduled to be launched from Baikonur cosmodrome in early 2001. This cooperative mission has presented a number of management, technical and logistical challenges on both sides. This paper makes an attempt to review and document such experiences.

  3. Modeling the hydrothermal circulation and the hydrogen production at the Rainbow site with Cast3M

    NASA Astrophysics Data System (ADS)

    Perez, F.; Mügler, C.; Charlou, J.; Jean-baptiste, P.

    2012-12-01

    On the Mid-Atlantic Ridge, the Rainbow venting site is described as an ultramafic-hosted active hydrothermal site and releases high fluxes of methane and hydrogen [1, 2]. This behavior has first been interpreted as the result of serpentinization processes. But geochemical reactions involving olivine and plagioclase assemblages, and leading to chlorite, tremolite, talc and magnetite assemblages, could contribute to the observed characteristics of the exiting fluid [2]. The predominance of one of these geochemical reactions or their coexistence strongly depend on the hydrothermal fluid circulation. We developed and validated a 2D/3D numerical model using a Finite Volume method to simulate heat driven fluid flows in the framework of the Cast3M code [3, 4]. We also developed a numerical model for hydrogen production and transport that is based on experimental studies of the serpentinization processes [5-6]. This geochemical model takes into account the exothermic and water-consuming behavior of the serpentinization reaction and it can be coupled to our thermo-hydrogeological model. Our simulations provide temperatures, mass fluxes and venting surface areas very close to those estimated in-situ [7]. We showed that a single-path model [8] was necessary to simulate high values such as the in-situ measured temperatures and estimated water mass fluxes of the Rainbow site [7]. This single-path model will be used to model the production and transport of hydrogen at the Rainbow hydrothermal site. References [1]Charlou et al. (2010) AGU Monograph series. [2]Seyfried et al. (2011) Geochim. Cosmochim. Acta 75, 1574-1593. [3]http://www-cast3m.cea.fr. [4]Martin & Fyfe (1970) Chem. Geol. 6, 185-202. [5] Marcaillou et al. (2011) Earth and Planet. Sci. Lett. 303, 281-290. [6]Malvoisin et al. (2012) JGR, 117, B01104. [7]Perez et al. (2012) submited to Computational Geosciences. [8]Lowell & Germanovich (2004) AGU, Washington DC, USA.

  4. Observation of 20-400 kHz fluctuations in the U-3M torsatron

    NASA Astrophysics Data System (ADS)

    Dreval, M. B.; Yakovenko, Yu. V.; Sorokovoy, E. L.; Slavnyj, A. S.; Pavlichenko, R. O.; Kulaga, A. E.; Zamanov, N. V.; Hirose, A.

    2016-02-01

    First observations of quasi-coherent fluctuations in the frequency range of 20-400 kHz in Alfvén-wave-heated plasmas of the U-3M torsatron are presented. The excitation conditions of these modes depend on the radio frequency antenna type and the plasma density, the appearance of the modes correlating with the presence of both suprathermal electrons and high-energy ions in the plasma, which supports our opinion that the modes are excited by energetic particles. Complicated evolution of the mode frequencies with abrupt changes at the instants of plasma confinement transitions is observed at the initial stage of each discharge. The frequencies become stable at the stage of the plasma current flattop. Raw estimates show that toroidicity-induced Alfvén eigenmodes could be responsible for the 150-400 kHz fluctuations. Low-frequency 20-70 kHz bursts are observed during plasma confinement transitions. The poloidal mode number of one of these bursts with the frequency of 20 kHz burst was determined to be m = 2. This mode rotated in the electron diamagnetic rotation direction with a frequency lower than the geodesic acoustic mode frequency and can be identified as a drift-sound-type mode.

  5. The RCT 1.3 m robotic telescope: broadband color transformation and extinction calibration

    SciTech Connect

    Strolger, L.-G.; Gott, A. M.; Carini, M.; Gelderman, R.; Laney, C. D.; McGruder, C.; Engle, S.; Guinan, E.; Treffers, R. R.; Walter, D. K.

    2014-03-01

    The Robotically Controlled Telescope (RCT) 1.3 m telescope, formerly known as the Kitt Peak National Observatory (KPNO) 50 inch telescope, has been refurbished as a fully robotic telescope, with an autonomous scheduler to take full advantage of the observing site without the requirement of a human presence. Here we detail the current configuration of the RCT and present, as a demonstration of its high-priority science goals, the broadband UBVRI photometric calibration of the optical facility. In summary, we find the linear color transformation and extinction corrections to be consistent with similar optical KPNO facilities, to within a photometric precision of 10% (at 1σ). While there were identified instrumental errors that likely added to the overall uncertainty, associated with since-resolved issues in engineering and maintenance of the robotic facility, a preliminary verification of this calibration gave a good indication that the solution is robust, perhaps to a higher precision than this initial calibration implies. The RCT has been executing regular science operations since 2009 and is largely meeting the science requirements set during its acquisition and redesign.

  6. Characteristics of ICR-produced peripheral plasma in the Uragan-3M torsatron

    NASA Astrophysics Data System (ADS)

    Besedin, N. T.; Chechkin, V. V.; Fomin, I. P.

    Some plasma parameters outside the confinement volume near the last closed magnetic surface (LCMS) and in the divertor fluxes were studied by probe and microwave techniques during ICR production and heating of the plasma in the Uragan-3M torsatron. When moving around the LCMS, the steepness of the radial density, electron temperature, and potential profiles increase with distance away from the 'rib' of the LCMS. The quasi-steady radial electric field E(sub r) near the LCMS exceeds 100 V/cm and is directed outwards, opposite to the calculated ambipolar electric field inside the confinement volume. It is shown that the total flow of the diverted plasma in the spacing between two helical windings consists of a weakly mobile non-resonant component which is presumably formed at the periphery due to ionization, and a component whose value and poloidal location are sensitive to resonance conditions for RF power absorption, this flow being apparently formed by a plasma diffusing through the LCMS and/or generated near the LCMS, where the filed E(sub r) is localized. Based on plasma parameters measurements after the RF pulse is switched off, a qualitative model of peripheral plasma dynamics after the end of the RF heating is constructed.

  7. Oxidation, Reduction, and Condensation of Alcohols over (MO3)3 (M=Mo, W) Nanoclusters

    SciTech Connect

    Fang, Zongtang; Li, Zhenjun; Kelley, Matthew S.; Kay, Bruce D.; Li, Shenggang; Hennigan, Jamie M.; Rousseau, Roger J.; Dohnalek, Zdenek; Dixon, David A.

    2014-10-02

    The reactions of deuterated methanol, ethanol, 1-propanol, 1-butanol, 2-propanol, 2-butanol and t-butanol over cyclic (MO3)3 (M = Mo, W) clusters were studied experimentally with temperature programmed desorption (TPD) and theoretically with coupled cluster CCSD(T) theory and density functional theory. The reactions of two alcohols per M3O9 cluster are required to provide agreement with experiment for D2O release, dehydrogenation and dehydration. The reaction begins with the elimination of water by proton transfers and forms an intermediate dialkoxy species which can undergo further reaction. Dehydration proceeds by a β hydrogen transfer to a terminal M=O. Dehydrogenation takes place via an α hydrogen transfer to an adjacent MoVI = O atom or a WVI metal center with redox involved for M = Mo and no redox for M = W. The two channels have comparable activation energies. H/D exchange to produce alcohols can take place after olefin is released or via the dialkoxy species depending on the alcohol and the cluster. The Lewis acidity of the metal center with WVI being larger than MoVI results in the increased reactivity of W3O9 over Mo3O9 for dehydrogenation and dehydration.

  8. Analysis of temperature-time data from 3 m drillholes at Crystal Hot Springs, Utah

    SciTech Connect

    Howell, J.; Chapman, D.S.

    1986-01-01

    A method for determining the background geothermal gradient values through the analysis of temperature measurements at multiple depths to 3 m and recorded over a time span of several days is presented. The analysis is based on the amplitude decay and phase shift of temperature waves with depth. Diurnal and other high frequency temperature variations are used to compute thermal diffusivities which in turn are used to model and remove the effect of the annual temperature wave. The analysis considers both a homogeneous half space and a two layer medium consisting of an overburden of finite thickness overlying a semi-infinite substratum. The method was tested in three holes in the Crystal Hot Springs geothermal field. Temperatures in each hole were recorded once a minute over a period of three days with a probe containing thermistors at eight different depths. Five of the thermistors were positioned at shallow depths (less than or equal to 0.5 m) to monitor diurnal and other high frequency waves and three at greater depths (greater than or equal to 1 m) to measure lower frequency variations. Since measurements were recorded at only three sites, the accuracy and reliability of the method is not fully evaluated. Potential problems to the method resulting from inaccurate model parameters and convective heat transport are investigated.

  9. Cleaning of inner vacuum surfaces in the Uragan-3M facility by radio-frequency discharges

    SciTech Connect

    Lozin, A. V. Moiseenko, V. E.; Grigor’eva, L. I.; Kozulya, M. M.; Kulaga, A. E.; Lysoivan, A. I.; Mironov, Yu. K.; Pavlichenko, R. O.; Romanov, V. S.; Chernyshenko, V. Ya.; Chechkin, V. V.; Collaboration: Uragan-3M Team

    2013-08-15

    A method for cleaning vacuum surfaces by a low-temperature (T{sub e} ∼ 10 eV) relatively dense (n{sub e} ≈ 10{sup 12} cm{sup −3}) plasma of an RF discharge was developed and successfully applied at the Uragan-3M torsatron. The convenience of the method is that it can be implemented with the same antenna system and RF generators that are used to produce and heat the plasma in the operating mode and does not require retuning the frequencies of the antennas and RF generators. The RF discharge has a high efficiency from the standpoint of cleaning vacuum surfaces. After performing a series of cleanings by the low-temperature RF discharge plasma (about 20000 pulses), (i) the intensity of the CIII impurity line was substantially reduced, (ii) a quasi-steady operating mode with a duration of up to 50 ms, a plasma density of n{sub e} ≈ 10{sup 12} cm{sup −3}, and an electron temperature of up to T{sub e} ∼ 1 keV was achieved, and (iii) mass spectrometric analysis of the residual gas in the chamber indicated a significant reduction in the impurity content.

  10. GRACOS: Scalable and Load Balanced P3M Cosmological N-body Code

    NASA Astrophysics Data System (ADS)

    Shirokov, Alexander; Bertschinger, Edmund

    2010-10-01

    The GRACOS (GRAvitational COSmology) code, a parallel implementation of the particle-particle/particle-mesh (P3M) algorithm for distributed memory clusters, uses a hybrid method for both computation and domain decomposition. Long-range forces are computed using a Fourier transform gravity solver on a regular mesh; the mesh is distributed across parallel processes using a static one-dimensional slab domain decomposition. Short-range forces are computed by direct summation of close pairs; particles are distributed using a dynamic domain decomposition based on a space-filling Hilbert curve. A nearly-optimal method was devised to dynamically repartition the particle distribution so as to maintain load balance even for extremely inhomogeneous mass distributions. Tests using 800(3) simulations on a 40-processor beowulf cluster showed good load balance and scalability up to 80 processes. There are limits on scalability imposed by communication and extreme clustering which may be removed by extending the algorithm to include adaptive mesh refinement.

  11. Clinical evaluation of the 3M Littmann Electronic Stethoscope Model 3200 in 150 cats.

    PubMed

    Blass, Keith A; Schober, Karsten E; Bonagura, John D; Scansen, Brian A; Visser, Lance C; Lu, Jennifer; Smith, Danielle N; Ward, Jessica L

    2013-10-01

    Detection of murmurs and gallops may help to identify cats with heart disease. However, auscultatory findings may be subject to clinically relevant observer variation. The objective of this study was to evaluate an electronic stethoscope (ES) in cats. We hypothesized that the ES would perform at least as well as a conventional stethoscope (CS) in the detection of abnormal heart sounds. One hundred and fifty consecutive cats undergoing echocardiography were enrolled prospectively. Cats were ausculted with a CS (WA Tycos Harvey Elite) by two observers, and heart sounds were recorded digitally using an ES (3M Littmann Stethoscope Model 3200) for off-line analysis. Echocardiography was used as the clinical standard method for validation of auscultatory findings. Additionally, digital recordings (DRs) were assessed by eight independent observers with various levels of expertise, and compared using interclass correlation and Cohen's weighted kappa analyses. Using the CS, a heart murmur (n = 88 cats) or gallop sound (n = 17) was identified in 105 cats, whereas 45 cats lacked abnormal heart sounds. There was good total agreement (83-90%) between the two observers using the CS. In contrast, there was only moderate agreement (P <0.001) between results from the CS and the DRs for murmurs, and poor agreement for gallops. The CS was more sensitive compared with the DRs with regard to murmurs and gallops. Agreement among the eight observers was good-to-excellent for murmur detection (81%). In conclusion, DRs made with the ES are less sensitive but comparably specific to a CS at detecting abnormal heart sounds in cats.

  12. ErbB3 mRNA leukocyte levels as a biomarker for major depressive disorder

    PubMed Central

    2012-01-01

    Background In recent years, the identification of peripheral biomarkers that are associated with psychiatric diseases, such as Major Depressive Disorder (MDD), has become relevant because these biomarkers may improve the efficiency of the differential diagnosis process and indicate targets for new antidepressant drugs. Two recent candidate genes, ErbB3 and Fgfr1, are growth factors whose mRNA levels have been found to be altered in the leukocytes of patients that are affected by bipolar disorder in a depressive state. On this basis, the aim of the study was to determine if ErbB3 and Fgfr1 mRNA levels could be a biomarkers of MDD. Methods We measured by Real Time PCR ErbB3 and Fgfr1 mRNA expression levels in leukocytes of MDD patients compared with controls. Successively, to assess whether ErbB3 mRNA levels were influenced by previous antidepressant treatment we stratified our patients sample in two cohorts, comparing drug-naive versus drug-free patients. Moreover, we evaluated the levels of the transcript in MDD patients after 12 weeks of antidepressant treatment, and in prefrontal cortex of rats stressed and treated with an antidepressant drug of the same class. Results These results showed that ErbB3 but not Fgfr1 mRNA levels were reduced in leukocytes of MDD patients compared to healthy subjects. Furthermore, ErbB3 levels were not affected by antidepressant treatment in either human or animal models Conclusions Our data suggest that ErbB3 might be considered as a biomarker for MDD and that its deficit may underlie the pathopsysiology of the disease and is not a consequence of treatment. Moreover the study supports the usefulness of leukocytes as a peripheral system for identifying biomarkers in psychiatric diseases. PMID:22989054

  13. Initial Operation and Checkout of Stratospheric Aerosol Gas Experiment and Meteor-3M Satellite

    NASA Technical Reports Server (NTRS)

    Habib, Shahid; Makridenko, L.; Chu, W.; Salikhov, R.; Moore, A.; Trepte, C.; Cisewski, M.

    2002-01-01

    Under a joint agreement between the National Aeronautics and Space Agency (NASA) and the Russian Aviation and Space Agency (RASA), the Stratospheric Aerosol Gas Experiment III (SAGE III) instrument was launched in low earth orbit on December 10,2001 aboard the Russian Meteor-3M satellite from the Baikonur Cosmodrome. SAGE III is a spectrometer that measures attenuated radiation in the 282 nm to 1550 nm wavelength range to obtain the vertical profiles of ozone, aerosols, and other chemical species that are critical in studying the trends for the global climate change phenomena. This instrument version is more advanced than any of the previous versions and has more spectral bands, elaborate data gathering and storage, and intelligent terrestrial software. There are a number of Russian scientific instruments aboard the Meteor satellite in addition to the SAGE III instrument. These instruments deal with land imaging and biomass changes, hydro-meteorological monitoring, and helio-geophysical research. This mission was under development for over a period of six years and offered a number of unique technical and program management challenges for both Agencies. SAGE III has a long space heritage, and four earlier versions of this instrument have flown in space for nearly two decades now. In fact, SAGE II, the fourth instrument, is still flying in space on NASA s Earth Radiation Budget Satellite (ERBS), and has been providing important atmospheric data over the last 18 years. It has provided vital ozone and aerosol data in the mid latitudes and has contributed vastly in ozone depletion research. Ball Aerospace built the instrument under Langley Research Center s (LaRC) management. This paper presents innovative approaches deployed by the SAGE III and the Meteor teams in performing the initial on-orbit checkout. It further documents a number of early science results obtained by deploying low risk, carefully coordinated procedures in resolving the serious operational issues

  14. Initial operation and checkout of stratospheric aerosol gas experiment and Meteor-3M satellite

    NASA Astrophysics Data System (ADS)

    Habib, Shahid; Makridenko, Leonid; Chu, William P.; Salikhov, Rashid; Moore, Alvah S., Jr.; Trepte, Charles R.; Cisewski, Michael S.

    2003-04-01

    Under a joint agreement between the National Aeronautics and Space Agency (NASA) and the Russian Aviation and Space Agency (RASA), the Stratospheric Aerosol Gas Experiment III (SAGE III) instrument was launched in low earth orbit on December 10, 2001 aboard the Russian Meteor-3M(1) satellite from the Baikonur Cosmodrome. SAGE III is a spectrometer that measures attenuated radiation in the 282 nm to 1550 nm wavelength range to obtain the vertical profiles of ozone, aerosols, and other chemical species that are critical in studying the trends for the global climate change phenomena. This instrument version is more advanced than any of the previous versions and has more spectral bands, elaborate data gathering and storage, and intelligent terrestrial software. There are a number of Russian scientific instruments aboard the Meteor satellite in addition to the SAGE III instrument. These instruments deal with land imaging and biomass changes, hydro-meteorological monitoring, and helio-geophysical research. This mission was under development for over a period of six years and offered a number of unique technical and program management challenges for both Agencies. SAGE III has a long space heritage, and four earlier versions of this instrument have flown in space for nearly two decades now. In fact, SAGE II, the fourth instrument, is still flying in space on NASA's Earth Radiation Budget Satellite (ERBS), and has been providing important atmospheric data over the last 18 years. It has provided vital ozone and aerosol data in the mid latitudes and has contributed vastly in ozone depletion research. Ball Aerospace built the instrument under Langley Research Center's (LaRC) management. This paper presents the process and approach deployed by the SAGE III and the Meteor teams in performing the initial on-orbit checkout. It further documents a number of early science results obtained by deploying low risk, carefully coordinated procedures in resolving the serious operational

  15. PLANET ENGULFMENT BY {approx}1.5-3 M{sub sun} RED GIANTS

    SciTech Connect

    Kunitomo, M.; Ikoma, M.; Sato, B.; Ida, S.; Katsuta, Y.

    2011-08-20

    Recent radial-velocity surveys for GK clump giants have revealed that planets also exist around {approx}1.5-3 M{sub sun} stars. However, no planets have been found inside 0.6 AU around clump giants, in contrast to solar-type main-sequence stars, many of which harbor short-period planets such as hot Jupiters. In this study, we examine the possibility that planets were engulfed by host stars evolving on the red-giant branch (RGB). We integrate the orbital evolution of planets in the RGB and helium-burning phases of host stars, including the effects of stellar tide and stellar mass loss. Then we derive the critical semimajor axis (or the survival limit) inside which planets are eventually engulfed by their host stars after tidal decay of their orbits. Specifically, we investigate the impact of stellar mass and other stellar parameters on the survival limit in more detail than previous studies. In addition, we make detailed comparisons with measured semimajor axes of planets detected so far, which no previous study has done. We find that the critical semimajor axis is quite sensitive to stellar mass in the range between 1.7 and 2.1 M{sub sun}, which suggests a need for careful comparison between theoretical and observational limits of the existence of planets. Our comparison demonstrates that all planets orbiting GK clump giants that have been detected are beyond the survival limit, which is consistent with the planet-engulfment hypothesis. However, on the high-mass side (>2.1M{sub sun}), the detected planets are orbiting significantly far from the survival limit, which suggests that engulfment by host stars may not be the main reason for the observed lack of short-period giant planets. To confirm our conclusion, the detection of more planets around clump giants, especially with masses {approx}> 2.5M{sub sun}, is required.

  16. [The experience of using Filtek Bulk Fill (3M ESPE) - the advantages of bulk fill flowable restoratives].

    PubMed

    Sharova, T N

    2014-01-01

    The paper presents clinical cases illustrating the advantages of bulk fill flowable restoratives, such as Filtek Bulk Fill (3M ESPE). The material showed good clinical results for class I and class II restorations.

  17. Modifications to Langley 0.3-m TCT adaptive wall software for heavy gas test medium, phase 1 studies

    NASA Technical Reports Server (NTRS)

    Murthy, A. V.

    1992-01-01

    The scheme for two-dimensional wall adaptation with sulfur hexafluoride (SF6) as test gas in the NASA Langley Research Center 0.3-m Transonic Cryogenic Tunnel (0.3-m TCT) is presented. A unified version of the wall adaptation software has been developed to function in a dual gas operation mode (nitrogen or SF6). The feature of ideal gas calculations for nitrogen operation is retained. For SF6 operation, real gas properties have been computed using the departure function technique. Installation of the software on the 0.3-m TCT ModComp-A computer and preliminary validation with nitrogen operation were found to be satisfactory. Further validation and improvements to the software will be undertaken when the 0.3-m TCT is ready for operation with SF6 gas.

  18. 2D and 3D Ultrasonographic Evaluation of Fetal Midface Hypoplasia in Two Cases with 3-M Syndrome.

    PubMed

    Vimercati, A; Chincoli, A; de Gennaro, A C; DʼAddario, V; Cicinelli, E

    2016-07-01

    This paper highlights the utility of 2D and 3D ultrasonography in the prenatal diagnosis of facial dysmorphisms suggestive of very rare syndromes such as 3-M syndrome. Two pregnant women at risk for fetal skeletal dysplasias were referred to our clinic for 2D/3D ultrasound scan in the second trimester of pregnancy. Only one of the patients had a familial history of 3-M syndrome. Karyotyping and genetic testing of abortion material were performed in both cases. 2D ultrasonography revealed growth retardation of the long bones in both cases. In the case without a familial history of the syndrome, 2D and 3D ultrasonography showed an absence of nasal bones and a flat malar region suggestive of 3-M syndrome, although the difficult differential diagnosis included other dysmorphic growth disorders with prenatal onset. The karyotype was normal but the pregnancy was terminated in both cases. Postmortem examination confirmed 3-M syndrome as indicated by prenatal findings. In high-risk cases with a familial history of 3-M syndrome, prenatal diagnosis of 3-M syndrome is possible by analyzing fetal DNA. In the absence of risk, a definitive prenatal diagnosis is often not possible but may be suspected in the presence of shortened long bones, normal head size and typical flattened malar region (midface hypoplasia) shown on complementary 2D and 3D sonograms. 2D and 3D ultrasonography has been shown to offer reliable information for the prenatal study of skeletal and facial anomalies and can be useful if there is a suspicion of 3-M syndrome in a pregnancy not known to be at risk.

  19. 2D and 3D Ultrasonographic Evaluation of Fetal Midface Hypoplasia in Two Cases with 3-M Syndrome

    PubMed Central

    Vimercati, A.; Chincoli, A.; de Gennaro, A. C.; DʼAddario, V.; Cicinelli, E.

    2016-01-01

    This paper highlights the utility of 2D and 3D ultrasonography in the prenatal diagnosis of facial dysmorphisms suggestive of very rare syndromes such as 3-M syndrome. Two pregnant women at risk for fetal skeletal dysplasias were referred to our clinic for 2D/3D ultrasound scan in the second trimester of pregnancy. Only one of the patients had a familial history of 3-M syndrome. Karyotyping and genetic testing of abortion material were performed in both cases. 2D ultrasonography revealed growth retardation of the long bones in both cases. In the case without a familial history of the syndrome, 2D and 3D ultrasonography showed an absence of nasal bones and a flat malar region suggestive of 3-M syndrome, although the difficult differential diagnosis included other dysmorphic growth disorders with prenatal onset. The karyotype was normal but the pregnancy was terminated in both cases. Postmortem examination confirmed 3-M syndrome as indicated by prenatal findings. In high-risk cases with a familial history of 3-M syndrome, prenatal diagnosis of 3-M syndrome is possible by analyzing fetal DNA. In the absence of risk, a definitive prenatal diagnosis is often not possible but may be suspected in the presence of shortened long bones, normal head size and typical flattened malar region (midface hypoplasia) shown on complementary 2D and 3D sonograms. 2D and 3D ultrasonography has been shown to offer reliable information for the prenatal study of skeletal and facial anomalies and can be useful if there is a suspicion of 3-M syndrome in a pregnancy not known to be at risk. PMID:27453585

  20. Coordinated observations of F region 3 m field-aligned plasma irregularities associated with medium-scale traveling ionospheric disturbances

    NASA Astrophysics Data System (ADS)

    Lin, F. F.; Wang, C. Y.; Su, C. L.; Shiokawa, K.; Saito, S.; Chu, Y. H.

    2016-04-01

    Three meter field-aligned irregularities (3 m FAIs) associated with medium-scale traveling ionospheric disturbances (MSTIDs) that occurred on 5 February 2008 were observed by using the Chung-Li 52 MHz coherent scatter radar. Interferometry measurements show that the plasma structures responsible for the 3 m FAI echoes are in a clumpy shape with a horizontal dimension of about 10-78 km in a height range of 220-300 km. In order to investigate the dynamic behaviors of the plasma irregularities at different scales in the bottomside of F region, the VHF radar echo structures from the 3 m FAIs combined with the 630 nm airglow images provided by the Yonaguni all-sky imager are compared and analyzed. The results show that the radar echoes were located at the west edge of the depletion zones of the 630 nm airglow image of the MSTIDs. The bulk echo structures of the 3 m FAIs drifted eastward at a mean trace velocity of about 30 m/s that is in general agreement with the zonal trace velocity of the MSTIDs shown in the 630 nm airglow images. These results suggest that the observed F region 3 m FAIs for the present case can be regarded as the targets that are frozen in the local region of the MSTIDs. In addition, the radar-observed 3 m FAI echo intensity and spectral width bear high correlations to the percentage variations of the 630 nm emission intensity. These results seem to suggest that through the nonlinear turbulence cascade process, the MSTID-associated 3 m FAIs are very likely generated from the kilometer-scale plasma irregularities with large amplitude excited by the gradient drift instability.

  1. P3 mAb: An Immunogenic Anti-NeuGcGM3 Antibody with Unusual Immunoregulatory Properties.

    PubMed

    Martínez, Darel; Rodríguez, Nely; Griñán, Tania; Rondón, Teresa; Vázquez, Ana María; Pérez, Rolando; Hernández, Ana María

    2012-01-01

    P3 is a murine IgM mAb that recognize N-glycosylated gangliosides, sulfatides, and antigens expressed in melanoma, breast, and lung human tumors. This antibody has the ability to trigger an IgG antibody response in the syngeneic BALB/c model, even when it is administered in the absence of adjuvant or carrier protein. The mechanism by which the P3 mAb, a self-immunoglobulin, induce this immune response in the absence of co-stimulatory or classical danger signals is still unknown. In the present paper we show that the high immunogenicity of P3 mAb depends not only on CD4 but also on CD8(+) T cells, since the depletion of CD8(+) or CD4(+) T cells led to the loss of P3 mAb immunogenicity in the syngeneic model. Furthermore, the immunization with P3 mAb enhanced the recovery of the CD8(+) T cell population in mice treated with an anti-CD8a antibody. Additionally, the immunization with P3 mAb restored the capacity of immunosuppressed mice to reject allogeneic tumors, a mechanism mediated by the action of CD8(+) T cells. Finally, in mice with cyclophosphamide induced lymphopenia, the administration of P3 mAb accelerated the recovery of both CD4(+) and CD8(+) T cells. These results show new possibilities for B and CD8(+) T cells interactions during the immune response elicited by a self-protein. Furthermore they point to P3 mAb as a potential interesting candidate for the treatment of immunosuppressed patients.

  2. Anisotropic surface melting in lyotropic cubic crystals. Part 1: Pn3m/L1 interface, poor faceting

    NASA Astrophysics Data System (ADS)

    Grenier, J.; Plötzing, T.; Rohe, D.; Pieranski, P.

    2006-02-01

    From experiments with ice or metal crystals, in the vicinity of their crystal/liquid/vapor triple points, it is known that melting of crystals starts on their surfaces and is anisotropic. It is shown here by direct observations under an optical microscope that this anisotropic surface melting phenomenon occurs also in lyotropic systems. In the case of C12EO2/water mixture, it takes place in the vicinity of the peritectic Pn3m/L3/L1 triple point. Above the peritectic triple point, where the Pn3m and L1 phases coexist in the bulk, the surface of a Pn3m-in-L1 crystal is composed of (111)-type facets surrounded by rough surfaces. The angular junction suggests that rough surfaces are wet by a L3-like layer while facets stay “dry”. This is analogous to the pre-melting at rough surfaces in solid crystals. Upon cooling below the peritectic triple point, where L3 and L1 phases coexist in the bulk, a thick layer of the L3 phase grows from the pre-melted, rough Pn3m/L1 interface. Simultaneously, facets stay dry and their radius decreases. In this tri-phasic configuration, stable in a narrow temperature range, the L3/L1 and L3/Pn3m interfaces have shapes of constant mean curvature surfaces having common borders: edges of facets.

  3. Maternal uniparental isodisomy and heterodisomy on chromosome 6 encompassing a CUL7 gene mutation causing 3M syndrome.

    PubMed

    Sasaki, K; Okamoto, N; Kosaki, K; Yorifuji, T; Shimokawa, O; Mishima, H; Yoshiura, K-i; Harada, N

    2011-11-01

    We report a case of segmental uniparental maternal hetero- and isodisomy involving the whole of chromosome 6 (mat-hUPD6 and mat-iUPD6) and a cullin 7 (CUL7) gene mutation in a Japanese patient with 3M syndrome. 3M syndrome is a rare autosomal recessive disorder characterized by severe pre- and postnatal growth retardation that was recently reported to involve mutations in the CUL7 or obscurin-like 1 (OBSL1) genes. We encountered a patient with severe growth retardation, an inverted triangular gloomy face, an inverted triangle-shaped head, slender long bones, inguinal hernia, hydrocele testis, mild ventricular enlargement, and mild mental retardation. Sequence analysis of the CUL7 gene of the patient revealed a homozygous missense mutation, c.2975G>C. Genotype analysis using a single nucleotide polymorphism array revealed two mat-hUPD and two mat-iUPD regions involving the whole of chromosome 6 and encompassing CUL7. 3M syndrome caused by complete paternal iUPD of chromosome 6 involving a CUL7 mutation has been reported, but there have been no reports describing 3M syndrome with maternal UPD of chromosome 6. Our results represent a combination of iUPDs and hUPDs from maternal chromosome 6 involving a CUL7 mutation causing 3M syndrome.

  4. Properties near magnetic instability of heavy-electron compounds Ce3M4Sn13 and La3M4Sn13, with M=Co, Rh and Ru

    NASA Astrophysics Data System (ADS)

    Ślebarski, Andrzej

    2015-02-01

    In this review, we report the thermodynamic, magnetic and electronic transport properties of the skutterudite-related Ce3M4Sn13 and La3M4Sn13 intermetallic compounds with M = Co, Rh and Ru, which display a variety of behaviours. Ce3M4Sn13 exhibit a large increase in C/T with a maximum value of about 4 JK-2mol-1Ce due to strong electron and short-range magnetic correlations. These compounds show a crossover from a magnetically correlated heavy-fermion state to a single impurity state in applied magnetic fields. In order to study the proximity of Ce3Co4Sn13 to the possible magnetic quantum critical point (QCP), we investigated the system of Ce3-xLaxCo4Sn13 alloys. We found the critical concentration ?, which separates the magnetically correlated state (?) from a single impurity state (?), however the low-T C(T)/T and the magnetic susceptibility behaviours are not characteristic of the QCP. With increasing of the magnetic field, resistivity follows power law behaviour for the samples ?, with n strongly field dependent. The ?-anomaly is discussed on the base of spin-fluctuation theory of Moriya and Takimoto. Specific heat data show that La3M4Sn13 are typical BCS superconductors, however, La3Rh4Sn13 and La3Ru4Sn13 exhibit a second superconducting phase, characteristic of inhomogeneous superconductors.

  5. Synthesis of new visible light active photocatalysts of Ba(In(1/3)Pb(1/3)M'(1/3))O3 (M' = Nb, Ta): a band gap engineering strategy based on electronegativity of a metal component.

    PubMed

    Hur, Su Gil; Kim, Tae Woo; Hwang, Seong-Ju; Park, Hyunwoong; Choi, Wonyong; Kim, Sung Jin; Kim, Sun Jin; Choy, Jin-Ho

    2005-08-11

    We have synthesized new, efficient, visible light active photocatalysts through the incorporation of highly electronegative non-transition metal Pb or Sn ions into the perovskite lattice of Ba(In(1/3)Pb(1/3)M'(1/3))O3 (M = Sn, Pb; M' = Nb, Ta). X-ray diffraction, X-ray absorption spectroscopic, and energy dispersive spectroscopic microprobe analyses reveal that tetravalent Pb or Sn ions exist in the B-site of the perovskite lattice, along with In and Nb/Ta ions. According to diffuse UV-vis spectroscopic analysis, the Pb-containing quaternary metal oxides Ba(In(1/3)Pb(1/3)M'(1/3))O3 possess a much narrower band gap (E(g) approximately 1.48-1.50 eV) when compared to the ternary oxides Ba(In(1/2)M'(1/2))O3 (E(g) approximately 2.97-3.30 eV) and the Sn-containing Ba(In(1/3)Sn(1/3)M'(1/3))O3 derivatives (E(g) approximately 2.85-3.00 eV). Such a variation of band gap energy upon the substitution is attributable to the broadening of the conduction band caused by the dissimilar electronegativities of the B-site cations. In contrast to the ternary or the Sn-substituted quaternary compounds showing photocatalytic activity under UV-vis irradiation, the Ba(In(1/3)Pb(1/3)M'(1/3))O3 compounds induce an efficient photodegradation of 4-chlorophenol under visible light irradiation (lambda > 420 nm). The present results highlight that the substitution of electronegative non-transition metal cations can provide a very powerful way of developing efficient visible light harvesting photocatalysts through tuning of the band structure of a semiconductive metal oxide.

  6. Spectral and statistical analysis of fluctuations in the SOL and diverted plasmas of the Uragan-3M torsatron

    NASA Astrophysics Data System (ADS)

    Beletskii, A. A.; Grigor'eva, L. I.; Sorokovoy, E. L.; Chechkin, V. V.; Sorokovoy, Y. L.; Volkov, Ye. D.; Burchenko, P. Ya.; Kulaga, A. Ye.; Tsybenko, S. A.; Lozin, A. V.; Slavnyj, A. S.; Lavrenovich, Yu. S.; Zamanov, N. V.; Mironov, Yu. K.; Romanov, V. S.

    2009-10-01

    In the l = 3/ m = 9 Uragan-3M (U3-M) torsatron ( R 0 = 1 m, ā ≈ 0.12 m, ι( ā)/2π ˜ 0.3) with an open helical divertor and a plasma produced and heated by RF fields (ω ≲ ωci), studies of low frequency (5-100 kHz) density and potential fluctuations in the SOL plasma and in the diverted plasma flows (DPFs), have been carried out. It is shown, that in the SOL to more (less) distantly located points relative to the last closed magnetic surface, higher (lower) frequency fluctuations are inherent. Such a spectral splitting in two sub-ranges occurs in the DPFs too. A peculiarity of the spatial distribution of DPF fluctuation spectra is that lower frequency fluctuations dominate on the ion toroidal B × ∇ B drift side. During L-H-like transition in U-3M simultaneously with strong E r shear formation, a suppression of lower frequency fluctuations and a decrease of local radial turbulent particle flux take place. Results are presented of investigation of plasma density fluctuations in SOL with the use of probability distribution function (PDF) analysis. Evaluations of skewness and kurtosis of fluctuations have been made. The analysis of I s fluctuations in DPF have been carried out in a similar way.

  7. Effect of 3M Coban Self-Adherent Wraps on edema and function of the burned hand: a case study.

    PubMed

    Lowell, M; Pirc, P; Ward, R S; Lundy, C; Wilhelm, D A; Reddy, R; Held, B; Bernard, J

    2003-01-01

    Edema and limited function are common acute problems associated with hand burns. This case study examined the effects of 3M Coban Self-Adherent Wraps on edema and function in a 59-year-old male (46% TBSA flame injury) with newly skin grafted dorsally burned hands. At the time of each dressing change, circumferential measurements were taken of both hands and weekly active range of motion and grip strength measurements were recorded. The nine-hole peg test was used to appraise dexterity. During the 4-week study period, there was less edema, greater active range of motion and grip strength, and greater dexterity in the hand with 3M Coban Self-Adherent Wraps as compared with the control hand. This case study suggests that 3M Coban Self-Adherent Wraps were effective in reducing edema in the skin-grafted hand after skin grafting. It further appeared that the reduced edema may have contributed to improved hand function and that 3M Coban Self-Adherent Wraps as a compressive dressing do not impede hand function

  8. Abscinazole-E3M, a practical inhibitor of abscisic acid 8′-hydroxylase for improving drought tolerance

    PubMed Central

    Takeuchi, Jun; Okamoto, Masanori; Mega, Ryosuke; Kanno, Yuri; Ohnishi, Toshiyuki; Seo, Mitsunori; Todoroki, Yasushi

    2016-01-01

    Abscisic acid (ABA) is an essential phytohormone that regulates plant water use and drought tolerance. However, agricultural applications of ABA have been limited because of its rapid inactivation in plants, which involves hydroxylation of ABA by ABA 8′-hydroxylase (CYP707A). We previously developed a selective inhibitor of CYP707A, (−)-Abz-E2B, by structurally modifying S-uniconazole, which functions as an inhibitor of CYP707A and as a gibberellin biosynthetic enzyme. However, its synthetic yield is too low for practical applications. Therefore, we designed novel CYP707A inhibitors, Abz-T compounds, that have simpler structures in which the 1,2,3-triazolyl ring of (−)-Abz-E2B has been replaced with a triple bond. They were successfully synthesised in shorter steps, resulting in greater yields than that of (−)-Abz-E2B. In the enzymatic assays, one of the Abz-T compounds, (−)-Abz-E3M, acted as a strong and selective inhibitor of CYP707A, similar to (−)-Abz-E2B. Analysis of the biological effects in Arabidopsis revealed that (−)-Abz-E3M enhanced ABA’s effects more than (−)-Abz-E2B in seed germination and in the expression of ABA-responsive genes. Treatment with (−)-Abz-E3M induced stomatal closure and improved drought tolerance in Arabidopsis. Furthermore, (−)-Abz-E3M also increased the ABA response in rice and maize. Thus, (−)-Abz-E3M is a more practical and effective inhibitor of CYP707A than (−)-Abz-E2B. PMID:27841331

  9. Evaluation of 3M Molecular Detection System and ANSR Pathogen Detection System for rapid detection of Salmonella from egg products.

    PubMed

    Hu, L; Ma, L M; Zheng, S; He, X; Wang, H; Brown, E W; Hammack, T S; Zhang, G

    2016-11-02

    Isothermal amplification assay is a novel simple detection technology that amplifies DNA with high speed, efficiency, and specificity under isothermal conditions. The objective of this study was to evaluate the effectiveness of the 3M Molecular Detection System (MDS) and ANSR Pathogen Detection System (PDS) for the detection of Salmonella in egg products as compared to the Food and Drug Administration's Bacteriological Analytical Manual (BAM) culture method and a modified culture method (3M MDS and ANSR PDS preferred method). Two Salmonella ser. Enteritidis (18579, PT4; CDC_2010K_1441, PT8), one Salmonella ser. Heidelberg (607310-1), and one Salmonella ser. Typhimurium (0723) isolates were used in this study. Seven wet egg products and 13 dry egg products were inoculated with these strains individually at 1 to 5 CFU/25 g. One set of test portions was prepared following FDA BAM procedures [with lactose broth (LB) as pre-enrichment broth]. Another set of test portions was prepared using buffered peptone water (BPW) as pre-enrichment broth, as instructed by the 2 detection systems. Results from 3M MDS and ANSR PDS were 100% in agreement with their BPW-based culture method results. When LB was used as pre-enrichment broth, the number of Salmonella positive test portions (80 tested), identified with the BAM, 3M MDS, and ANSR PDS, were 63, 61, and 60, respectively. In conclusion, both 3M MDS and ANSR PDS Salmonella assays were as effective as their BPW based culture methods and were equivalent to the BAM culture method for the detection of Salmonella in egg products. These sensitive isothermal assays can be used as rapid detection tools for Salmonella in egg products provided that BPW is used as pre-enrichment broth.

  10. Density functional theory studies on theelectronic, structural, phonon dynamicaland thermo-stability properties of bicarbonates MHCO3, M D Li, Na, K

    SciTech Connect

    Duan, Yuhua; Zhang, Bo; Sorescu, Dan C.; Johnson, Karl; Majzoub, Eric H; Luebke, David R.

    2012-07-01

    The structural, electronic, phonon dispersion and thermodynamic properties of MHCO3 (M D Li, Na, K) solids were investigated using density functional theory. The calculated bulk properties for both their ambient and the high-pressure phases are in good agreement with available experimental measurements. Solid phase LiHCO3 has not yet been observed experimentally. We have predicted several possible crystal structures for LiHCO3 using crystallographic database searching and prototype electrostatic ground state modeling. Our total energy and phonon free energy .FPH/ calculations predict that LiHCO3 will be stable under suitable conditions of temperature and partial pressures of CO2 and H2O. Our calculations indicate that the HCO􀀀 3 groups in LiHCO3 and NaHCO3 form an infinite chain structure through O#1; #1; #1;H#1; #1; #1;O hydrogen bonds. In contrast, the HCO􀀀 3 anions form dimers, .HCO􀀀 3 /2, connected through double hydrogen bonds in all phases of KHCO3. Based on density functional perturbation theory, the Born effective charge tensor of each atom type was obtained for all phases of the bicarbonates. Their phonon dispersions with the longitudinal optical–transverse optical splitting were also investigated. Based on lattice phonon dynamics study, the infrared spectra and the thermodynamic properties of these bicarbonates were obtained. Over the temperature range 0–900 K, the FPH and the entropies (S) of MHCO3 (M D Li, Na, K) systems vary as FPH.LiHCO3/ > FPH.NaHCO3/ > FPH.KHCO3/ and S.KHCO3/ > S.NaHCO3/ > S.LiHCO3/, respectively, in agreement with the available experimental data. Analysis of the predicted thermodynamics of the CO2 capture reactions indicates that the carbonate/bicarbonate transition reactions for Na and K could be used for CO2 capture technology, in agreement with experiments.

  11. N- and O-linked glycosylation site profiling of the human basic salivary proline-rich protein 3M.

    PubMed

    Manconi, Barbara; Cabras, Tiziana; Sanna, Monica; Piras, Valentina; Liori, Barbara; Pisano, Elisabetta; Iavarone, Federica; Vincenzoni, Federica; Cordaro, Massimo; Faa, Gavino; Castagnola, Massimo; Messana, Irene

    2016-05-01

    In the present study, we show that the heterogeneous mixture of glycoforms of the basic salivary proline-rich protein 3M, encoded by PRB3-M locus, is a major component of the acidic soluble fraction of human whole saliva in the first years of life. Reversed-phase high-performance liquid chromatography with high-resolution electrospray ionization mass spectrometry analysis of the intact proteoforms before and after N-deglycosylation with Peptide-N-Glycosidase F and tandem mass spectrometry sequencing of peptides obtained after Endoproteinase GluC digestion allowed the structural characterization of the peptide backbone and identification of N- and O-glycosylation sites. The heterogeneous mixture of the proteoforms derives from the combination of 8 different neutral and sialylated glycans O-linked to Threonine 50, and 33 different glycans N-linked to Asparagine residues at positions 66, 87, 108, 129, 150, 171, 192, and 213.

  12. Confinement bifurcation initiated by plasma current profile and toroidal electric field perturbations in the TUMAN-3M tokamak

    NASA Astrophysics Data System (ADS)

    Askinazi, L. G.; Bulanin, V. V.; Kornev, V. A.; Krikunov, S. V.; Lebedev, S. V.; Tukachinsky, A. S.; Vildjunas, M. I.; Zhubr, N. A.

    2011-03-01

    The results of the experimental study of confinement mode bifurcation performed on the TUMAN-3M tokamak are reported. As a trigger of confinement mode switching, plasma current ramp-up/-down or magnetic compression/decompression is used. It is found that the possibility and direction of confinement mode switching are correlated not with plasma current profile perturbation (peaking or broadening) but with the sign of toroidal electric field perturbation. A model connecting confinement bifurcation and toroidal electric field perturbation through the perturbation of the radial electric field is used to describe the phenomena observed in all eight scenarios investigated. This model ascribes the radial electric field generation to the non-compensated Ware drift of banana electrons at the TUMAN-3M peripheral plasma, where \

  13. On the multi-index (3 m-parametric) Mittag-Leffler functions, fractional calculus relations and series convergence

    NASA Astrophysics Data System (ADS)

    Paneva-Konovska, Jordanka

    2013-10-01

    In this paper we consider a family of 3 m-indices generalizations of the classical Mittag-Leffler function, called multi-index (3 m-parametric) Mittag-Leffler functions. We survey the basic properties of these entire functions, find their order and type, and new representations by means of Mellin-Barnes type contour integrals, Wright p Ψ q -functions and Fox H-functions, asymptotic estimates. Formulas for integer and fractional order integration and differentiations are found, and these are extended also for the operators of the generalized fractional calculus (multiple Erdélyi-Kober operators). Some interesting particular cases of the multi-index Mittag-Leffler functions are discussed. The convergence of series of such type functions in the complex plane is considered, and analogues of the Cauchy-Hadamard, Abel, Tauber and Littlewood theorems are provided.

  14. On the multi-index (3m-parametric) Mittag-Leffler functions, fractional calculus relations and series convergence

    NASA Astrophysics Data System (ADS)

    Paneva-Konovska, Jordanka

    2013-10-01

    In this paper we consider a family of 3m-indices generalizations of the classical Mittag-Leffler function, called multi-index (3m-parametric) Mittag-Leffler functions. We survey the basic properties of these entire functions, find their order and type, and new representations by means of Mellin-Barnes type contour integrals, Wright pΨq-functions and Fox H-functions, asymptotic estimates. Formulas for integer and fractional order integration and differentiations are found, and these are extended also for the operators of the generalized fractional calculus (multiple Erdélyi-Kober operators). Some interesting particular cases of the multi-index Mittag-Leffler functions are discussed. The convergence of series of such type functions in the complex plane is considered, and analogues of the Cauchy-Hadamard, Abel, Tauber and Littlewood theorems are provided.

  15. Engineered proteins with Pumilio/fem-3 mRNA binding factor scaffold to manipulate RNA metabolism.

    PubMed

    Wang, Yang; Wang, Zefeng; Tanaka Hall, Traci M

    2013-08-01

    Pumilio/fem-3 mRNA binding factor proteins are characterized by a sequence-specific RNA-binding domain. This unique single-stranded RNA recognition module, whose sequence specificity can be reprogrammed, has been fused with functional modules to engineer protein factors with various functions. We summarize the advances made with respect to developing RNA regulatory tools, as well as opportunities for the future.

  16. Heat flux measurements of Tb3M series (M=Co, Rh and Ru): Specific heat and magnetocaloric properties

    NASA Astrophysics Data System (ADS)

    Monteiro, J. C. B.; Lombardi, G. A.; dos Reis, R. D.; Freitas, H. E.; Cardoso, L. P.; Mansanares, A. M.; Gandra, F. G.

    2016-12-01

    We report on the magnetic properties and magnetocaloric effect (MCE) for the Tb3M series, with M=Co, Rh and Ru, obtained using a heat flux technique. The specific heat of Tb3Co and Tb3Rh are very similar, with a first order type transition occurring around 6 K below the magnetic ordering temperature without any corresponding feature on the magnetization. The slightly enhanced electronic specific heat, the Debye temperature around 150 K and the presence of the magnetic specific heat well above the ordering temperature are also characteristic of many other compounds of the R3M family (R=Rare Earth). The specific heat for Tb3Ru, however, presents two peaks at 37 K and 74 K. The magnetization shows that below the first peak the system presents an antiferromagnetic behavior and is paramagnetic above 74 K. We obtained a magnetocaloric effect for M=Co and Rh, -∆S=12 J/kg K, but for Tb3Ru it is less than 3 J/kg K (μ0∆H=5 T). We believe that the experimental results show that the MCE is directly related with the process of hybridization of the (R)5d-(M)d electrons that occurs in the R3M materials.

  17. Design of multichord Hα detector arrays for the U-3M torsatron and identification of rotating plasma perturbations

    NASA Astrophysics Data System (ADS)

    Dreval, M. B.; Shapoval, A. M.; Ozherelyev, F. I.; Makhov, M. M.

    2016-07-01

    An Hα camera has been designed and installed in the U-3M torsatron for spatially and temporally resolved measurements. This device provides fast measurements of the emission brightness profile in the noisy environment of the radio frequency (RF) heated plasma. Unusual topology of diagnostics and the data acquisition system are applied. All the system components, including digitizers, are assembled in a single unit. It allows the suppression of a low-frequency electromagnetic interference by eliminating the ground loops. And the suppression of RF noises is achieved by eliminating the signal interface cables and digital interface cables in the design. The Wi-Fi interface is used to prevent a ground loop in the data transfer stage. The achieved sensitivity of our diagnostics is high enough for measuring the Hα emission from the low-density (ne ≈ (1-2)ṡ1010 cm-3) plasma with a temporal resolution of about 20 μs in the noisy environment. Different types of Hα emission fluctuations within the frequency range of 1-5 kHz and poloidal mode numbers m = 0 and m = 5 have been observed in U-3M. A simple technique of the line-of-sight data analysis, based on the U-3M magnetic surface asymmetry, is proposed and used for the spatial localization of the rotating mode and for the determination of mode numbers and its poloidal rotation direction using a single Hα array.

  18. Double L{sub 3}M ionization of Pd induced by impact with medium-energy electrons

    SciTech Connect

    Cao, W.; Dousse, J.-Cl.; Hoszowska, J.; Kayser, Y.; Schenker, J.-L.; Kavcic, M.; Zitnik, M.

    2011-02-15

    The electron-induced L{sub 3}M two-step double ionization cross sections of metallic Pd were determined experimentally for incident electron beam energies ranging from the double ionization threshold up to 18 keV. The double L{sub 3}M ionization cross sections were derived from the intensity ratios (I{sub L{alpha}M}:I{sub L{alpha}}) of the resolved M satellites to the parent diagram lines. The sample was bombarded with monoenergetic electrons from an energy-tunable 20-kV electron gun. The diagram and M-satellite x-ray lines were measured by means of high-resolution x-ray spectroscopy, using a reflection-type von Hamos bent crystal spectrometer. The two-step partial cross sections were determined by subtracting from the measured total double ionization cross sections the contributions due to the shake process and L{sub 1}-L{sub 3}M{sub 4,5} Coster-Kronig transitions. Despite the thick target employed in the present study, the dependence of the two-step cross sections on the incoming electron energy could be derived using a target slice decomposition method. It is shown that the obtained energy dependence can be well reproduced by the semiempirical parametrization model of Pattard and Rost.

  19. Deposition of LaMO3 (M=Ni,Co,Cr,Al)-Oriented Films by Spray Combustion Flame Technique

    NASA Astrophysics Data System (ADS)

    Ichinose, Hiromichi; Shiwa, Yuzo; Nagano, Masamitsu

    1994-10-01

    LaMO3 (M=Ni,Co,Cr,Al) films were prepared on sintered alumina, sapphire (001) and MgO(100) at 500 900°C by spraying ultrasonically atomized aqueous solutions of nitrates into a combustion flame (spray combustion flame technique). LaNiO3 and LaCoO3 on MgO(100) crystallized in high-temperature phases (cubic) while LaCrO3 and LaAlO3 crystallized in room-temperature phases. LaMO3 (M=Ni,Co,Cr,Al) films on MgO(100) were highly oriented to (100), (100), (001) and (100), respectively, while the films on sintered alumina and sapphire were not. The electric resistivities of the dense LaMO3 (M=Ni,Co,Cr) films were as low as those of bulk ceramics. LaNiO3 film deposited on MgO above 700°C showed the lowest resistivity of about 6×10-6 Ω m. It was suggested that the reactivities of the constituent metal atoms with OH in the flame are associated with the preferred phase and the morphology of the films.

  20. Anti-CD3 mAb treatment cures PDL1-/-.NOD mice of diabetes but precipitates fatal myocarditis.

    PubMed

    Mfarrej, Bechara; Keir, Mary; Dada, Shirine; Trikudanathan, Subbulaxmi; Sayegh, Mohamed H; Sharpe, Arlene H; Guleria, Indira

    2011-07-01

    Anti-CD3 mAb is an effective therapy that can reverse diabetes in NOD mice and has therapeutic potential in patients with type 1 diabetes (T1D). We administered anti-CD3 to PDL1-/-.NOD mice in order to determine whether this treatment would reverse the development of diabetes in these mice. Mice injected with anti-CD3 mAb neonatally were protected from T1D. However, all of these anti-CD3 mAb treated PDL1-/-.NOD mice developed a wasting disease between 12 and 20 weeks of age with sudden deterioration and weight loss, leading to death within 3-5 days of development of illness. Histology revealed severe inflammation in the heart and skeletal muscles. These results suggest that deficiency of PDL1 in NOD background has the potential to lead to immune-mediated tissue damage in organs other than the pancreas, but this cannot be appreciated in PDL1-/-.NOD mice as the mice develop T1D at an early age and die from diabetes prior to manifesting other autoimmune diseases.

  1. Evaluation of 3M molecular detection assay (MDA) Salmonella for the detection of Salmonella in selected foods: collaborative study.

    PubMed

    Bird, Patrick; Fisher, Kiel; Boyle, Megan; Huffman, Travis; Benzinger, M Joseph; Bedinghaus, Paige; Flannery, Jonathan; Crowley, Erin; Agin, James; Goins, David; Benesh, DeAnn; David, John

    2013-01-01

    The 3M Molecular Detection Assay (MDA) Salmonella is used with the 3M Molecular Detection System for the detection of Salmonella spp. in food, food-related, and environmental samples after enrichment. The assay utilizes loop-mediated isothermal amplification to rapidly amplify Salmonella target DNA with high specificity and sensitivity, combined with bioluminescence to detect the amplification. The 3M MDA Salmonella method was compared using an unpaired study design in a multilaboratory collaborative study to the U.S. Department of Agriculture/Food Safety and Inspection Service-Microbiology Laboratory Guidebook (USDA/FSIS-MLG 4.05), Isolation and Identification of Salmonella from Meat, Poultry, Pasteurized Egg and Catfish Products for raw ground beef and the U.S. Food and Drug Administration/Bacteriological Analytical Manual (FDA/BAM) Chapter 5 Salmonella reference method for wet dog food following the current AOAC guidelines. A total of 20 laboratories participated. For the 3M MDA Salmonella method, raw ground beef was analyzed using 25 g test portions, and wet dog food was analyzed using 375 g test portions. For the reference methods, 25 g test portions of each matrix were analyzed. Each matrix was artificially contaminated with Salmonella at three inoculation levels: an uninoculated control level (0 CFU/test portion), a low inoculum level (0.2-2 CFU/test portion), and a high inoculum level (2-5 CFU/test portion). In this study, 1512 unpaired replicate samples were analyzed. Statistical analysis was conducted according to the probability of detection (POD). For the low-level raw ground beef test portions, the following dLPOD (difference between the POD of the reference and candidate method) values with 95% confidence intervals were obtained: -0.01 (-0.14, +0.12). For the low-level wet dog food test portions, the following dLPOD with 95% confidence intervals were obtained: -0.04 (-0.16, +0.09). No significant differences were observed in the number of positive

  2. SF3M 2.0: improvement of 3D photo-reconstruction interface based on freely available software

    NASA Astrophysics Data System (ADS)

    Castillo, Carlos; James, Michael R.; Pérez, Rafael; Gómez, Jose A.

    2016-04-01

    During recent years, a number of tools based on Structure-from-Motion algorithms have been released for full image-based 3D reconstruction either freely (e.g. Bundler, PMVS2, VisualSFM, MicMac) or commercially (e.g. Agisoft PhotoScan). The SF3M interface was developed in Matlab® to use link software developments (VisualSFM, CloudCompare) and new applications to create a semi-automated workflow including reconstruction, georeferencing and point-cloud filtering, and has been tested for gully erosion assessment with terrestrial images (Castillo et al., 2015). The main aim of this work to provide an improved freely-available and easy-to-use alternative for 3D reconstruction intended for public agencies, non-profit organisations, researchers and other stakeholders interested in 3D modelling. In this communication we present SF3M 2.0, a new version of the graphical user interface. In this case, the SfM module is based on MicMac, an open-software tool (Pierrot-Deseilligny and Cléry, 2011) which provides advanced features such as camera calibration and constrained bundle adjustment using ground control points. SF3M 2.0 will be tested in two scenarios: a) using the same ground-based image set tested in Castillo et al. (2015) to compare the performance of both versions and b) using aerial images taken from a helium balloon to assess a gully network in a 40-hectares catchment. In this study we explore the advantages of SF3M 2.0, explain its operation and evaluate its accuracy and performance. This tool will be also available for free download. References Castillo, C., James, M.R., Redel-Macías, M. D., Pérez, R., and Gómez, J.A.: SF3M software: 3-D photo-reconstruction for non-expert users and its application to a gully network, SOIL, 1, 583-594. Pierrot-Deseilligny, M and Cléry, I. APERO, an Open Source Bundle Adjusment Software for Automatic Calibration and Orientation of a Set of Images. Proceedings of the ISPRS Commission V Symposium, Image Engineering and Vision

  3. IF-combined smRNA FISH reveals interaction of MCPIP1 protein with IER3 mRNA

    PubMed Central

    Kochan, Jakub; Wawro, Mateusz

    2016-01-01

    ABSTRACT MCPIP1 and IER3 are recently described proteins essential for maintenance of immune homeostasis. IER3 is involved in the regulation of apoptosis and differentiation and has been shown lately to protect activated T cells and macrophages from apoptosis. MCPIP1 is an RNase critical for controlling inflammation-related mRNAs. MCPIP1 interacts with and degrades a set of stem-loop-containing mRNAs (including IL-6). Our results demonstrate the involvement of MCPIP1 in the regulation of IER3 mRNA levels. A dual luciferase assay revealed that over-expression of MCPIP1 resulted in a decrease of luciferase activity in the samples co-transfected with constructs containing luciferase CDS attached to IER3 3′UTR. We identified a stem-loop structure similar to that described to be important for destabilization of the IL-6 mRNA by MCPIP1. Examination of IER3 3′UTR sequence, structure and evolutionary conservation revealed that the identified stem-loop is buried within a bigger element. Deletion of this fragment abolished the regulation of IER3 3′UTR-containing transcript by MCPIP1. Finally, using immunofluorescence-combined single-molecule RNA FISH we have shown that the MCPIP1 protein co-localizes with IER3 mRNA. By this method we also proved that the presence of the wild-type NYN/PIN-like domain of MCPIP1 correlated with the decreased level of IER3 mRNA. RNA immunoprecipitation further confirmed the interaction of MCPIP1 with IER3 transcripts in vivo. PMID:27256408

  4. The impact of Ghana's R3M programme on the provision of safe abortions and postabortion care.

    PubMed

    Sundaram, Aparna; Juarez, Fatima; Ahiadeke, Clement; Bankole, Akinrinola; Blades, Nakeisha

    2015-10-01

    In 2006, in response to the high maternal mortality, driven largely by unsafe abortions, the government of Ghana, in partnership with other organizations, launched the reducing maternal mortality and morbidity (R3M) programme in seven districts in Greater Accra, Ashanti and Eastern, to improve comprehensive abortion care services. This article examines whether this intervention made a difference to the provision of safe abortion services and postabortion care (PAC). We also examine the role played by provider attitudes and knowledge of the abortion law, on providers with clinical training in service provision. Primary data on health care providers in Ghana, collected using a quasi-experimental design, were analysed using propensity score weighting. Apart from the treatment group, the sample included two controls: (1) Districts in Accra, Ashanti and Eastern, not exposed to the treatment; and (2) Districts from distant Brong Ahafo, also not exposed to the treatment. The findings show that providers in the treatment group are nearly 16 times as likely to provide safe abortions compared with their peers in Brong Ahafo, and ∼2.5 times as likely compared with providers in the other control group. R3M providers were also different from their peers in providing PAC. Associations between provider attitudes and knowledge of the law on both outcomes were either non-significant or inconsistent including for providers with clinical knowledge of abortion provision. Provider confidence however is strongly associated with service provision. We conclude that the R3M programme is helping safe abortion provision, with the differences being greater with control groups that are geographically distant, perhaps owing to lower contamination from movement of providers between facilities. Increasing provider confidence is key to improving both safe abortion provision and PAC.

  5. Enhanced translational efficiency of a novel transforming growth factor beta 3 mRNA in human breast cancer cells.

    PubMed Central

    Arrick, B A; Grendell, R L; Griffin, L A

    1994-01-01

    The mRNA for transforming growth factor beta 3 (TGF-beta 3) includes a long (1.1-kb) 5' noncoding region which exerts a potent inhibitory effect on translational efficiency. We now report that many human breast cancer cell lines (T47-D, SK-BR-3, ZR-75-1, and BT-474) express two mRNA species for TGF-beta 3: the 3.5-kb transcript previously described as the only TGF-beta 3 mRNA species in cells and a novel 2.6-kb transcript which lacks approximately 870 nucleotides from the 5' noncoding region. The 5' end of the shorter transcript was sequenced, establishing it to be a 5' truncation of the full-length TGF-beta 3 transcript. Estradiol decreased mRNA levels of both TGF-beta 3 mRNA transcripts to an equivalent degree in estrogen receptor-positive cells. In contrast, the synthetic progestin gestodene altered the relative abundance of the two transcripts, preferentially diminishing the expression of the 2.6-kb transcript. The potential for enhanced mRNA translation attributable to the shorter 5' noncoding region was evaluated by transfection of cells with chimeric plasmid constructs in which the transcription unit consisted of coding sequence for chloramphenicol acetyltransferase downstream of the 5' noncoding sequence from TGF-beta 3. The translational efficiency of chloramphenicol acetyltransferase-encoding mRNA containing the shorter 5' noncoding region of the 2.6-kb TGF-beta 3 transcript was approximately seven times greater than with the full-length 5' noncoding region of TGF-beta 3. Polysome analysis of TGF-beta 3 mRNA in SK-BR-3 cells supported the hypothesis that the 2.6-kb transcript was more actively engaged in translation. Images PMID:8264630

  6. The Effect of Spray Strips on a Model of the P3M-1 Flying Boat Hull

    NASA Technical Reports Server (NTRS)

    Dawson, John R

    1933-01-01

    This note presents the results of a series of tests made in the N.A.C.A. tank on a one-sixth full-size model of the hull and side floats of the Navy P3M-1 flying boat for the purpose of finding a method of reducing the amount of spray thrown into the propellers of this craft when taking off and landing. The model was tested without spray strips and with five different spray-strip arrangements. The best arrangement was an improvement over the bare hull with no spray strips, but the improvement was not sufficient to be satisfactory with the propellers in the designed position.

  7. Determination of the scattering lengths of gallium isotopes by neutron interferometry with PNO-apparatus in JRR-3M

    NASA Astrophysics Data System (ADS)

    Tomimitsu, H.; Hasegawa, Y.; Aizawa, K.; Kikuta, S.

    1999-01-01

    For carrying out experiments in the field of the so-called precise neutron optics (PNO), we have implemented special multi-purpose apparatus called the "PNO-apparatus" at JRR-3M. Making use of an Si triple-Laue (LLL) neutron interferometer with the PNO-apparatus, we successfully determined the coherent neutron scattering lengths of gallium isotopes, 69Ga and 71Ga. The results are 8.053±0.013 fm for 69Ga and 6.170±0.011 fm for 71Ga, respectively.

  8. Design and construction of 2 transonic airfoil models for tests in the NASA Langley C.3-M TCT

    NASA Technical Reports Server (NTRS)

    Schaechterle, G.; Ludewig, K. H.; Stanewsky, E.; Ray, E. J.

    1982-01-01

    As part of a NASA/DFVLR cooperation program two transonic airfoils were tested in the NASA Langley 0.3-m TCT. Model design and construction was carried out by DFVLR. The models designed and constructed performed extremely well under cryogenic conditions. Essentially no permanent changes in surface quality and geometric dimensions occurred during the tests. The aerodynamic results from the TCT tests which demonstrate the large sensitivity of the airfoil CAST 10-Z/DOAZ to Reynolds number changes compared well with results from other facilities at ambient temperatures.

  9. 3M: Hutchinson Plant Focuses on Heat Recovery and Cogeneration during Plan-Wide Energy-Efficiency Assessment

    SciTech Connect

    2003-06-01

    3M performed a plant-wide energy efficiency assessment at its Hutchinson, Minnesota, plant to identify energy- and cost-saving opportunities. Assessment staff developed four separate implementation packages that represented various combinations of energy-efficiency projects involving chiller consolidation, air compressor cooling improvements, a steam turbine used for cogeneration, and a heat recovery boiler for two of the plant's thermal oxidizers. Staff estimated that the plant could save 6 million kWh/yr in electricity and more than 200,000 MMBtu/yr in natural gas and fuel oil, and avoid energy costs of more than $1 million during the first year.

  10. Mutual transformation of light waves by reflection holograms in photorefractive crystals of the 4-bar 3m symmetry

    SciTech Connect

    Naunyka, V. N.; Shepelevich, V. V.

    2011-05-15

    The mutual transformation of light waves in the case of their simultaneous diffraction from a bulk reflection phase hologram, which was formed in a cubic photorefractive crystal of the 4-bar 3m symmetry class, has been studied. The indicator surfaces of the polarization-optimized values of the relative intensity of the object wave, which make it possible to determine the amplification of this wave for any crystal cut, are constructed. The linear polarization azimuths at which the energy exchange between the light waves reaches a maximum are found numerically for crystals of different cuts.

  11. Preparation and evaluation of 3 m open tubular capillary columns with a zwitterionic polymeric porous layer for liquid chromatography.

    PubMed

    Peng, Li; Zhu, Manman; Zhang, Lingyi; Liu, Haiyan; Zhang, Weibing

    2016-10-01

    A 3 m zwitterionic polymeric porous layer open tubular column (3 m × 25 μm id × 375 μm od) with a polymeric porous layer thickness of 4 μm was fabricated by the copolymerization of [2-(methacryloyloxy)ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide and N,N'-methylenebis(acrylamide). The effects of the diameter of the capillary, reaction temperature, and polymerization time on the preparation of the open tubular column were investigated. Characterized by scanning electron microscopy, the zwitterionic layer was observed to be rough and throughout the fused-silica capillary homogenously, which increased the phase ratio. The separation of neutral, basic, and acidic compounds demonstrates the strong hydrophilicity of the poly[2-(methacryloyloxy)ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide coating. In addition, the poly[2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide porous layer open tubular column was applied for the analysis of flavonoids from the rootstalk of licorice, revealing the potential in separating complex samples. The relative standard deviation of retention time for run-to-run (n = 5), day-to-day (n = 3), and column-to-column (n = 3) of toluene, N,N-dimethylformamide, formamide, and thiourea were below 1.2%, exhibiting good repeatability.

  12. A Rare Cause of Short Stature: 3M Syndrome in a Patient with Novel Mutation in OBSL1 Gene

    PubMed Central

    Keskin, Melikşah; Muratoğlu Şahin, Nursel; Kurnaz, Erdal; Bayramoğlu, Elvan; Savaş Erdeve, Şenay; Aycan, Zehra; Çetinkaya, Semra

    2017-01-01

    The Miller-McKusick-Malvaux (3M) syndrome is a rare autosomal disorder that can lead to short stature, dysmorphic features, and skeletal abnormalities with normal intelligence. A 16-month-old female patient had been referred to our clinic due to short stature. Case history revealed a birth weight of 1740 grams on the 39th week of gestation, with a birth length of 42 cm and no prior hereditary conditions of clinical significance in her family. On physical examination, her length was 67 cm [-3.6 standard deviation (SD) score], weight 7.2 kg (-2.9 SD score), and head circumference 42 cm (below 3rd percentile). She also had numerous characteristic physical features such as a triangular face, fleshy nose tip, a long philtrum, prominent mouth and lips, pointed chin, lumbar lordosis, and prominent heels. As her growth retardation had a prenatal onset and the physical examination results were suggestive of a characteristic profile, the diagnosis of 3M syndrome was strongly considered. Genetic assessment of the patient revealed a novel homozygous p.T45Nfs*40 mutation in the OBSL1 gene. It is recommended that physicians pay further attention to this condition in the differential diagnosis of children with severe short stature. PMID:27796265

  13. In situ study of the R{bar 3}c-R{bar 3}m orientational disorder in calcite.

    SciTech Connect

    Antao, S. M.; Hassan, I.; Mulder, W. H.; Lee, P. L.; Toby, B. H.; X-Ray Science Division; Univ. of West Indies

    2009-01-01

    The temperature dependences of the crystal structure and intensities of the (113) and (211) reflections in calcite, CaCO{sub 3}, were studied using Rietveld structure refinements based on synchrotron powder X-ray diffraction data. Calcite transforms from R{bar 3}c to R{bar 3}m at about T{sub c} = 1240 K. A CO{sub 3} group occupies, statistically, two positions with equal frequency in the disordered R{bar 3}m phase, but with unequal frequency in the partially ordered R{bar 3}c phase. One position for the CO{sub 3} group is rotated by 180{sup o} with respect to the other. The unequal occupancy of the two orientations in the partially ordered R{bar 3}c phase is obtained directly from the occupancy factor, x, for the O1 site and gives rise to the order parameter, S = 2x - 1. The a cell parameter shows a negative thermal expansion at low T, followed by a plateau region at higher T, then a steeper contraction towards T{sub c}, where the CO{sub 3} groups disorder in a rapid process. Using a modified Bragg-Williams model, fits were obtained for the order parameter S, and for the intensities of the (113) and (211) reflections.

  14. Dopamine receptor D3 mRNA expression in human lymphocytes is negatively correlated with the personality trait of persistence.

    PubMed

    Czermak, Christoph; Lehofer, Michael; Renger, Helmut; Wagner, Elke M; Lemonis, Leonidas; Rohrhofer, Alfred; Schauenstein, Konrad; Liebmann, Peter M

    2004-05-01

    It has been proposed that neurotransmitter receptor expression in peripheral immune cells reflects expression of these receptors in the brain. To test this "peripheral marker hypothesis", we compared mRNA expression of the dopamine receptors D3 (DRD3) and D4 (DRD4) in peripheral blood lymphocytes (PBL) to personality traits assessed with the Temperament and Character Inventory (TCI) in 50 healthy and unmedicated Caucasian individuals. A shared variance of at least 17% (p=0.016) between DRD3 mRNA expression in PBL and the personality trait of persistence was found. As personality traits have been generally assumed polygenic with a single gene accounting for rarely more than 1-2% of observed variance in a trait, this result lends further support to the peripheral marker hypothesis for DRD3 mRNA expression in PBL. It may also suggest a significant role for the DRD3 in the neurobiology of persistence and point to an interesting link between personality and functioning of the immune system.

  15. Hydrogeological and geochemical modeling of hydrothermal fluids circulation in active ultramafic-hosted systems under CAST3M

    NASA Astrophysics Data System (ADS)

    Perez, F.; Mugler, C.; Jean-Baptiste, P.; Charlou, J. L.; Donval, J.; Vidal, O.; Marcailloux, C.; Munoz, M.

    2010-12-01

    Hydrothermal circulation at mid-ocean ridges is a fundamental process that impacts the transfer of energy and water from the interior of the Earth to the Crust, Hydrosphere and biosphere. Along the Mid-Atlantic Ridge (MAR), at precisely located ultramafic-hosted systems, important fluxes of heat, hydrogen and Iron are observed (Charlou et al., 2010 AGU Monograph series). It is now demonstrated that high and low-temperature hydrothermal activity and mantle degassing are indicators of ongoing serpentinization process. For a real understanding of this process and to estimate heat and hydrogen fluxes, numerical modeling leant on field data and laboratory experiments can yield results of interest. We thus developed a thermo-hydrogeological numerical model using a Finite Volume method to simulate heat driven fluid flows in geological layers, encoded under CAST3M, and presented here. For homogeneous medias, we successfully obtained exiting fluid temperatures that natural hydrothermal fluids usually reach. Considering laboratory experiments, we coupled, under CAST3M, our thermo-hydrogeological model to a geochemical model of serpentinization reaction. This last model is based on a reaction front velocity model calibrated by laboratory experiments. Primary results are presented here.

  16. About improving efficiency of the P3 M algorithms when computing the inter-particle forces in beam dynamics

    NASA Astrophysics Data System (ADS)

    Kozynchenko, Alexander I.; Kozynchenko, Sergey A.

    2017-03-01

    In the paper, a problem of improving efficiency of the particle-particle- particle-mesh (P3M) algorithm in computing the inter-particle electrostatic forces is considered. The particle-mesh (PM) part of the algorithm is modified in such a way that the space field equation is solved by the direct method of summation of potentials over the ensemble of particles lying not too close to a reference particle. For this purpose, a specific matrix ;pattern; is introduced to describe the spatial field distribution of a single point charge, so the ;pattern; contains pre-calculated potential values. This approach allows to reduce a set of arithmetic operations performed at the innermost of nested loops down to an addition and assignment operators and, therefore, to decrease the running time substantially. The simulation model developed in C++ substantiates this view, showing the descent accuracy acceptable in particle beam calculations together with the improved speed performance.

  17. Characteristics of the three-half-turn-antenna-driven RF discharge in the Uragan-3M torsatron

    SciTech Connect

    Grigor’eva, L. I.; Chechkin, V. V. Moiseenko, V. E.; Grekov, D. L.; Pavlichenko, R. O.; Lozin, A. V.; Tarasov, I. K.; Kulaga, A. Ye.; Zamanov, N. V.; Tretiak, K. K.; Kozulya, M. M.; Beletskii, A. A.; Kasilov, A. A.; Mironov, Yu. K.; Romanov, V. S.; Voitsenya, V. S.

    2015-12-15

    In the ℓ = 3 Uragan-3M torsatron hydrogen plasma is produced by RF fields in the Alfvén range of frequencies (ω ≤ ω{sub ci}). The initial (target) plasma with the line-averaged density of units 10{sup 12} cm{sup −3} is produced by a frame antenna with a broad spectrum of generated parallel wavenumbers. After this, to heat the plasma and bring its density to ∼10{sup 13} cm{sup –3}, another, shorter wavelength three-half-turn antenna with large transverse currents is used. The behavior of the density, electron temperature, and loss of the plasma supported by the three-half-turn antenna is studied depending on the RF power fed to the antenna and initial values of the density and electron temperature supplied by the frame antenna.

  18. Trends in (LaMnO3)n/(SrTiO3)m superlattices with varying layer thicknesses

    PubMed Central

    Jilili, J.; Cossu, F.; Schwingenschlögl, U.

    2015-01-01

    We investigate the thickness dependence of the structural, electronic, and magnetic properties of (LaMnO3)n/(SrTiO3)m (n, m = 2, 4, 6, 8) superlattices using density functional theory. The electronic structure turns out to be highly sensitive to the onsite Coulomb interaction. In contrast to bulk SrTiO3, strongly distorted O octahedra are observed in the SrTiO3 layers with a systematic off centering of the Ti atoms. The systems favour ferromagnetic spin ordering rather than the antiferromagnetic spin ordering of bulk LaMnO3 and all show half-metallicity, while a systematic reduction of the minority spin band gaps as a function of the LaMnO3 and SrTiO3 layer thicknesses originates from modifications of the Ti dxy states. PMID:26323361

  19. NaxMV(PO4)3 (M = Mn, Fe, Ni) Structure and Properties for Sodium Extraction.

    PubMed

    Zhou, Weidong; Xue, Leigang; Lü, Xujie; Gao, Hongcai; Li, Yutao; Xin, Sen; Fu, Gengtao; Cui, Zhiming; Zhu, Ye; Goodenough, John B

    2016-12-14

    NASICON (Na(+) super ionic conductor) structures of NaxMV(PO4)3 (M = Mn, Fe, Ni) were prepared, characterized by aberration-corrected STEM and synchrotron radiation, and demonstrated to be durable cathode materials for rechargeable sodium-ion batteries. In Na4MnV(PO4)3, two redox couples of Mn(3+)/Mn(2+) and V(4+)/V(3+) are accessed with two voltage plateaus located at 3.6 and 3.3 V and a capacity of 101 mAh g(-1) at 1 C. Furthermore, the Na4MnV(PO4)3 cathode delivers a high initial efficiency of 97%, long durability over 1000 cycles, and good rate performance to 10 C. The robust framework structure and stable electrochemical performance makes it a reliable cathode materials for sodium-ion batteries.

  20. Measurement of recovery temperature on an airfoil in the Langley 0.3-m transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Johnson, C. B.; Adcock, J. B.

    1981-01-01

    Experimental measurements of recovery temperature were made on an airfoil in the Langley 0.3-m Transonic Cryogenic Tunnel at Mach numbers of 0.60 and 0.84 over a Reynolds number per meter range from about 15,000,000 to about 335,000,000. The measured recovery temperatures were considerably below those associated with ideal-gas ambient temperature wind tunnels. This difference was accentuated as the stagnation pressure increased and the total temperature decreased. A boundary-layer code modified for use with cryogenic nitrogen adequately predicted the measured adiabatic wall temperature at all conditions. A quantitative, on-line assessment of the nonadiabatic condition of a model can be made during the operation of a cryogenic wind tunnel by using a correlation for the adiabatic wall temperature which is only a function of total temperature, total pressure, and local Mach number on the model.

  1. Design and use of a double crystal diffractometer for very small angle neutron scattering at JRR-3M

    NASA Astrophysics Data System (ADS)

    Aizawa, K.; Tomimitsu, H.

    1995-02-01

    The double crystal diffractometer (DCD) for very small angle neutron scattering (VSANS) in the precise neutron optics (PNO) apparatus on a 3G beam hole at JRR-3M is described. The DCD consists of a nondispersive (1, - 1) setting of 111 reflection of silicon single crystals with a sample between two crystals and is set on a vibration isolator table in a constant temperature chamber. The peak intensity of a rocking curve without a sample is 2200 cps at a detector position and the signal to noise ratio is 1.6 × 10 4 in a typical experiment. VSANS measurements for silica powder samples reveal that the q-range is available between 2 × 10 -4 and 6 × 10 -2 nm -1.

  2. Dry rehydratable film method for rapid enumeration of coliforms in foods (3M Petrifilm Rapid Coliform Count plate): collaborative study.

    PubMed

    Kinneberg, Karen M; Lindberg, Kathryn G

    2002-01-01

    A rehydratable dry-film plating method for coliforms in foods, the 3M Petrifilm Rapid Coliform Count plate method, was compared with the U.S. Food and Drug Administration's Bacteriological Analytical Manual method for nondairy foods and the American Public Health Association's Standard Methods for the Examination of Dairy Products (SMEDP) method for dairy foods. Six food types, vanilla ice cream, cheddar cheese, fresh refrigerated uncooked pasta, wheat flour, prepared frozen macaroni and cheese, and frozen hash browns, were analyzed for coliforms by 11 collaborating laboratories. For each food product tested, the collaborators received 8 blind samples consisting of a control sample and 3 levels of inoculated sample, each in duplicate. The mean log counts for the methods were comparable. The repeatability and reproducibility variances of the Petrifilm Rapid Coliform Count method at 14 and 24 h were not significantly different from those of the standard methods.

  3. Expanding on #YouDoYou: Reflections from the 2015 Cohort of 3M National Student Fellows on Exploring Authenticity in Education

    ERIC Educational Resources Information Center

    Baek, Justine; Shah, Wali; Spencer, Vrindy; Thompson, Piper Riley; Young, Karen; Zowmi, Aniqah

    2016-01-01

    The fourth cohort of 3M National Student Fellows explores the current state of our post-secondary education system across Canada and opportunities to further tune into practice in order to pursue an authentic and meaningful academic life. Six of the 2015 3M National Student Fellows propose recommendations for decision-makers at post-secondary…

  4. PMHS impact response in 3 m/s and 8 m/s nearside impacts with abdomen offset.

    PubMed

    Miller, Carl S; Madura, Nathaniel H; Schneider, Lawrence W; Klinich, Kathleen D; Reed, Matthew P; Rupp, Jonathan D

    2013-11-01

    Lateral impact tests were performed using seven male post-mortem human subjects (PMHS) to characterize the force-deflection response of contacted body regions, including the lower abdomen. All tests were performed using a dual-sled, side-impact test facility. A segmented impactor was mounted on a sled that was pneumatically accelerated into a second, initially stationary sled on which a subject was seated facing perpendicular to the direction of impact. Positions of impactor segments were adjusted for each subject so that forces applied to different anatomic regions, including thorax, abdomen, greater trochanter, iliac wing, and thigh, could be independently measured on each PMHS. The impactor contact surfaces were located in the same vertical plane, except that the abdomen plate was offset 5.1 cm towards the subject. The masses of the sleds and the force- deflection characteristics of the energy-absorbing interface material between the sleds were set to provide the impactor sled with a velocity profile that matched the average driver door velocity history produced in a series of side NCAP tests. Impactor padding was also selected so that average ATD pelvis and thorax responses from the same series of side NCAP tests were reproduced when the ATD used in these tests was impacted using the average door-velocity history. Each subject was first impacted on one side of the body using an initial impactor speed of 3 m/s. If a post-test CT scan and strain-gage data revealed two or fewer non-displaced rib fractures, then the PMHS was impacted on the contralateral side of the body at a speed of 8 m/s or 10 m/s. The results of tests in the 3 m/s and 8 m/s conditions were used to develop force-deflection response corridors for the abdomen, force history response corridors for the pelvis (iliac wing and greater trochanter), the midthigh, and the thorax. Response corridors for the lateral acceleration of the pelvis were also developed. Future work will compare side impact ATD

  5. Novel Lignan and Stilbenoid Mixture Shows Anticarcinogenic Efficacy in Preclinical PC-3M-luc2 Prostate Cancer Model

    PubMed Central

    Laajala, Teemu D.; Smeds, Annika; Eckerman, Christer; Holmbom, Bjarne; Saarinen, Niina M.; Aittokallio, Tero; Mäkelä, Sari I.

    2014-01-01

    Prostate cancer is the most common cancer of men in the Western world, and novel approaches for prostate cancer risk reduction are needed. Plant-derived phenolic compounds attenuate prostate cancer growth in preclinical models by several mechanisms, which is in line with epidemiological findings suggesting that consumption of plant-based diets is associated with low risk of prostate cancer. The objective of this study was to assess the effects of a novel lignan-stilbenoid mixture in PC-3M-luc2 human prostate cancer cells in vitro and in orthotopic xenografts. Lignan and stilbenoid –rich extract was obtained from Scots pine (Pinus sylvestris) knots. Pine knot extract as well as stilbenoids (methyl pinosylvin and pinosylvin), and lignans (matairesinol and nortrachelogenin) present in pine knot extract showed antiproliferative and proapoptotic efficacy at ≥40 μM concentration in vitro. Furthermore, pine knot extract derived stilbenoids enhanced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induced apoptosis already at ≥10 μM concentrations. In orthotopic PC-3M-luc2 xenograft bearing immunocompromized mice, three-week peroral exposure to pine knot extract (52 mg of lignans and stilbenoids per kg of body weight) was well tolerated and showed anti-tumorigenic efficacy, demonstrated by multivariate analysis combining essential markers of tumor growth (i.e. tumor volume, vascularization, and cell proliferation). Methyl pinosylvin, pinosylvin, matairesinol, nortrachelogenin, as well as resveratrol, a metabolite of pinosylvin, were detected in serum at total concentration of 7−73 μM, confirming the bioavailability of pine knot extract derived lignans and stilbenoids. In summary, our data indicates that pine knot extract is a novel and cost-effective source of resveratrol, methyl pinosylvin and other bioactive lignans and stilbenoids. Pine knot extract shows anticarcinogenic efficacy in preclinical prostate cancer model, and our in vitro data

  6. Steady state hemodynamic and energetic characterization of the Penn State/3M Health Care Total Artificial Heart.

    PubMed

    Weiss, W J; Rosenberg, G; Snyder, A J; Pierce, W S; Pae, W E; Kuroda, H; Rawhouser, M A; Felder, G; Reibson, J D; Cleary, T J; Ford, S K; Marlotte, J A; Nazarian, R A; Hicks, D L

    1999-01-01

    Total Artificial Heart (TAH) development at Penn State University and 3M Health Care has progressed from design improvements and manufacturing documentation to in vitro and in vivo testing to characterize the system's hemodynamic response and energetic performance. The TAH system is completely implantable and intended for use as an alternative to transplantation. It includes a dual pusher plate pump and rollerscrew actuator, welded electronics and battery assembly, transcutaneous energy transmission system, telemetry, and a compliance chamber. In vitro testing was conducted on a Penn State mock circulatory loop with glycerol/water solution at body temperature. Tests were performed to characterize the preload and afterload response, left atrial pressure control, and power consumption. A sensitive preload response was demonstrated with left atrial pressure safely maintained at less than 15 mm Hg for flow rates up to 7.5 L/min. Variations in aortic pressure and pulmonary vascular resistance were found to have minimal effects on the preload sensitivity and left atrial pressure control. In vivo testing of the completely implanted system in its final configuration was carried out in two acute studies using implanted temperature sensors mounted on the electronics, motor, and energy transmission coil in contact with adjacent tissue. The mean temperature at the device-tissue interface was less than 4 degrees C above core temperature.

  7. Elevated extrahepatic expression and secretion of mammary-associated serum amyloid A 3 (M-SAA3) into colostrum.

    PubMed

    McDonald, T L; Larson, M A; Mack, D R; Weber, A

    2001-12-01

    Mammary-associated serum amyloid A 3 (M-SAA3) was secreted at highly elevated levels in bovine, equine and ovine colostrum and found at lower levels in milk 4 days postparturition. N-terminal sequencing of the mature M-SAA3 protein from all the three species revealed a conserved four amino acid motif (TFLK) within the first eight residues. This motif has not been reported to be present in any of the hepatically-produced acute phase SAA (A-SAA) isoforms. Cloning of the bovine M-Saa3 cDNA from mammary gland epithelial cells revealed an open reading frame that encoded a precursor protein of 131 amino acids which included an 18 amino acid signal peptide. The predicted 113 residue mature M-SAA3 protein had a theoretical molecular mass of 12,826Da that corresponded with the observed 12.8kDa molecular mass obtained for M-SAA3 in immunoblot analysis. The high abundance of this extrahepatically produced SAA3 isoform in the colostrum of healthy animals suggests that M-SAA3 may play an important functional role associated with newborn adaptation to extrauterine life and possibly mammary tissue remodeling.

  8. SALMO and S3M: A Saliva Model and a Single Saliva Salt Model for Equilibrium Studies

    PubMed Central

    De Stefano, Concetta

    2015-01-01

    A model of synthetic saliva (SALMO, SALiva MOdel) is proposed for its use as standard medium in in vitro equilibrium and speciation studies of real saliva. The concentrations come out from the literature analysis of the composition of both real saliva and synthetic saliva. The chief interactions of main inorganic components of saliva, as well as urea and amino acids, are taken into account on the basis of a complex formation model, which also considers the dependence of the stability constants of these species on ionic strength and temperature. These last features allow the modelling of the speciation of saliva in different physiological conditions deriving from processes like dilution, pH, and temperature changes. To simplify equilibrium calculations, a plain approach is also proposed, in order to take into account all the interactions among the major components of saliva, by considering the inorganic components of saliva as a single 1 : 1 salt (MX), whose concentration is cMX = (1/2)∑ci (ci = analytical concentration of all the ions) and z ion charge calculated as z=±(I/cMX)1/2 = ±1.163. The use of the Single Saliva Salt Model (S3M) considerably reduces the complexity of the systems to be investigated. In fact, only four species deriving from internal ionic medium interactions must be considered. PMID:25733975

  9. An intracellular redox sensor for reactive oxygen species at the M3-M4 linker of GABAAρ1 receptors

    PubMed Central

    Beltrán González, Andrea N; Gasulla, Javier; Calvo, Daniel J

    2014-01-01

    Background and Purpose Reactive oxygen species (ROS) are normally involved in cell oxidative stress but also play a role as cellular messengers in redox signalling; for example, modulating the activity of neurotransmitter receptors and ion channels. However, the direct actions of ROS on GABAA receptors were not previously demonstrated. In the present work, we studied the effects of ROS on GABAAρ1 receptor function. Experimental Approach GABAAρ1 receptors were expressed in oocytes and GABA-evoked responses electrophysiologically recorded in the presence or absence of ROS. Chemical protection of cysteines by selective sulfhydryl reagents and site-directed mutagenesis studies were used to identify protein residues involved in ROS actions. Key Results GABAAρ1 receptor-mediated responses were significantly enhanced in a concentration-dependent and reversible manner by H2O2. Potentiating effects were attenuated by a free radical scavenger, lipoic acid or an inhibitor of the Fenton reaction, deferoxamine. Each ρ1 subunit contains only three cysteine residues, two extracellular at the Cys-loop (C177 and C191) and one intracellular (C364) at the M3-M4 linker. Mutant GABAAρ1 receptors in which C364 was exchanged by alanine were completely insensitive to modulation, implying that this site, rather than a cysteine in the Cys-loop, is essential for ROS modulation. Conclusion and Implications Our results show that the function of GABAAρ1 receptors is enhanced by ROS and that the intracellular C364 is the sensor for ROS actions. PMID:24428763

  10. SALMO and S3M: A Saliva Model and a Single Saliva Salt Model for Equilibrium Studies.

    PubMed

    Crea, Francesco; De Stefano, Concetta; Milea, Demetrio; Pettignano, Alberto; Sammartano, Silvio

    2015-01-01

    A model of synthetic saliva (SALMO, SALiva MOdel) is proposed for its use as standard medium in in vitro equilibrium and speciation studies of real saliva. The concentrations come out from the literature analysis of the composition of both real saliva and synthetic saliva. The chief interactions of main inorganic components of saliva, as well as urea and amino acids, are taken into account on the basis of a complex formation model, which also considers the dependence of the stability constants of these species on ionic strength and temperature. These last features allow the modelling of the speciation of saliva in different physiological conditions deriving from processes like dilution, pH, and temperature changes. To simplify equilibrium calculations, a plain approach is also proposed, in order to take into account all the interactions among the major components of saliva, by considering the inorganic components of saliva as a single 1 : 1 salt (MX), whose concentration is c MX = (1/2)∑c i (c i = analytical concentration of all the ions) and z ion charge calculated as z=±(I/c MX)(1/2) = ±1.163. The use of the Single Saliva Salt Model (S3M) considerably reduces the complexity of the systems to be investigated. In fact, only four species deriving from internal ionic medium interactions must be considered.

  11. Calculation of design load for the MOD-5A 7.3 mW wind turbine system

    NASA Technical Reports Server (NTRS)

    Mirandy, L.; Strain, J. C.

    1995-01-01

    Design loads are presented for the General Electric MOD-SA wind turbine. The MOD-SA system consists of a 400 ft. diameter, upwind, two-bladed, teetered rotor connected to a 7.3 mW variable-speed generator. Fatigue loads are specified in the form of histograms for the 30 year life of the machine, while limit (or maximum) loads have been derived from transient dynamic analysis at critical operating conditions. Loads prediction was accomplished using state of the art aeroelastic analyses developed at General Electric. Features of the primary predictive tool - the Transient Rotor Analysis Code (TRAC) are described in the paper. Key to the load predictions are the following wind models: (1) yearly mean wind distribution; (2) mean wind variations during operation; (3) number of start/shutdown cycles; (4) spatially large gusts; and (5) spatially small gusts (local turbulence). The methods used to develop statistical distributions from load calculations represent an extension of procedures used in past wind programs and are believed to be a significant contribution to Wind Turbine Generator analysis. Test/theory correlations are presented to demonstrate code load predictive capability and to support the wind models used in the analysis. In addition MOD-5A loads are compared with those of existing machines. The MOD-5A design was performed by the General Electric Company, Advanced Energy Program Department, under Contract DEN3-153 with NASA Lewis Research Center and sponsored by the Department of Energy.

  12. Control system design for the MOD-5A 7.3 mW wind turbine generator

    NASA Technical Reports Server (NTRS)

    Barton, Robert S.; Hosp, Theodore J.; Schanzenbach, George P.

    1995-01-01

    This paper provides descriptions of the requirements analysis, hardware development and software development phases of the Control System design for the MOD-5A 7.3 mW Wind Turbine Generator. The system, designed by General Electric Company, Advanced Energy Programs Department, under contract DEN 3-153 with NASA Lewis Research Center and DOE, provides real time regulation of rotor speed by control of both generator torque and rotor torque. A variable speed generator system is used to provide both airgap torque control and reactive power control. The wind rotor is designed with segmented ailerons which are positioned to control blade torque. The central component of the control system, selected early in the design process, is a programmable controller used for sequencing, alarm monitoring, communication, and real time control. Development of requirements for use of aileron controlled blades and a variable speed generator required an analytical simulation that combined drivetrain, tower and blade elastic modes with wind disturbances and control behavior. An orderly two phase plan was used for controller software development. A microcomputer based turbine simulator was used to facilitate hardware and software integration and test.

  13. MPO4:Nd3+ (M=Ca, Gd), Luminomagnetic Nanophosphors with Optical and Magnetic Features for Multimodal Imaging Applications

    NASA Astrophysics Data System (ADS)

    Rightsell, Chris; Mimun, Lawrence C.; Kumar, Ajith G.; Sardar, Dhiraj K.

    2015-03-01

    Nanomaterials with multiple functionalities play a very important role in several high technology applications. A major area of such applications is the biomedical industry, where contrast agents with multiple imaging modalities can provide better results than conventional materials. Many of the contrast agents available now have drawbacks such as toxicity, photobleaching, low contrast, size restrictions, and overall cost of the imaging system. Rare-earth doped inorganic nanophosphors are alternatives to circumvent several of these issues, together with the added advantage of super high resolution imaging due to the excellent near infrared sensitivity of the phosphors. In addition to optical imaging features, by adding a magnetic ion such as Gd3+ at suitable lattice positions, the phosphor can be made magnetic, yielding dual imaging functionalities. In this research, we are presenting the optical and magnetic imaging features of sub-nanometer size MPO4:Nd3+ (M=Ca, Gd) phosphors for the potential application of these nanophosphors as multimodal contrast agents. Cytotoxicity, in vitro and in vivo imaging, penetration depth etc. are studied for various phosphor compositions, and optimized compositions are explored. This research was funded by the National Science Foundation Partnerships for Research and Education in Materials (NSF-PREM) Grant N0-DMR-0934218.

  14. Deposition of LaMO 3 (M=Co, Cr, Al) films by spray pyrolysis in inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Ichinose, Hiromichi; Katsuki, Hiroaki; Nagano, Masamitsu

    1994-11-01

    LaMO 3 (M=Co, Cr, Al) films were prepared on substrates by introducing ultrasonically atomized metal nitrate solutions into an inductively coupled plasma under atmospheric pressure (spray-ICP technique). Dense perovskite-type oxide films of LaCoO 3 and LaCrO 3 were obtained at 600-900°C, while the LaAiO 3 films consisted of loosely packed aggregates. Deposition rates of the films were 6-35 nm/min at 600-900°C. The high temperature phases (cubic) of LaCoO 3 and LaAlO 3 crystallized due to effect of grain size. LaCrO 3 film crystallized in the room temperature phase (orthorhombic). LaCoO 3 was highly oriented to (100) on MgO(100), and LaCrO 3 to (011) and (101) on sapphire(001). Lowest electric resistivities of LaCoO 3 and LaCrO 3 film on MgO were 9.8X10 -3 and 2.7X10 -1 Ω m, respectively, at room temperature.

  15. De novo somatic mutations in components of the PI3K-AKT3-mTOR pathway cause hemimegalencephaly

    PubMed Central

    Lee, Jeong Ho; Huynh, My; Silhavy, Jennifer L; Kim, Sangwoo; Dixon-Salazar, Tracy; Heiberg, Andrew; Scott, Eric; Bafna, Vineet; Hill, Kiley J; Collazo, Adrienne; Funari, Vincent; Russ, Carsten; Gabriel, Stacey B; Mathern, Gary W; Gleeson, Joseph G

    2015-01-01

    De novo somatic mutations in focal areas are well documented in diseases such as neoplasia but are rarely reported in malformation of the developing brain. Hemimegalencephaly (HME) is characterized by overgrowth of either one of the two cerebral hemispheres. The molecular etiology of HME remains a mystery. The intractable epilepsy that is associated with HME can be relieved by the surgical treatment hemispherectomy, allowing sampling of diseased tissue. Exome sequencing and mass spectrometry analysis in paired brain-blood samples from individuals with HME (n = 20 cases) identified de novo somatic mutations in 30% of affected individuals in the PIK3CA, AKT3 and MTOR genes. A recurrent PIK3CA c.1633G>A mutation was found in four separate cases. Identified mutations were present in 8–40% of sequenced alleles in various brain regions and were associated with increased neuronal S6 protein phosphorylation in the brains of affected individuals, indicating aberrant activation of mammalian target of rapamycin (mTOR) signaling. Thus HME is probably a genetically mosaic disease caused by gain of function in phosphatidylinositol 3-kinase (PI3K)-AKT3-mTOR signaling. PMID:22729223

  16. Criticality calculations for the VR-1 reactor with IRT-3M-HEU fuel and IRT-4MLEU fuel.

    SciTech Connect

    Hanan, N. A.; Matos, J. E.

    2007-01-17

    At The request of the Czech Technical University in Prague, ANL has performed independent verification calculations using the MCNP Monte Carlo code for three core configurations of the VR-1 reactor: a current core configuration B1 with HEU (36%) IRT-3M fuel assemblies and planned core configurations C1 and C2 with LEU (19.7%) IRT-4M fuel assemblies. Details of these configurations were provided to ANL by CTU. For core configuration B1, criticality calculations were performed for two sets of control rod positions provided to ANL by CTU. For core configurations C1 and C2, criticality calculations were done for cases with all control rods at the top positions, all control rods at the bottom positions, and two critical states of the reactor for different control rod positions. In addition, sensitivity studies for variation of the {sup 235}U mass in each fuel assembly and variation of the fuel meat and cladding thicknesses in each of the fuel tubes were done for the C1 core configuration. Finally the reactivity worth of the individual control rods was calculated for the B1, C1, and C2 core configurations.

  17. Effect of solvent, temperature and pressure on the stability of chiral and perovskite metal formate frameworks of [NH2NH3][M(HCOO)3] (M = Mn, Fe, Zn).

    PubMed

    Mączka, Mirosław; Pasińska, Katarzyna; Ptak, Maciej; Paraguassu, Waldeci; da Silva, Tercio Almeida; Sieradzki, Adam; Pikul, Adam

    2016-11-23

    We report the synthesis, crystal structure, and thermal, Raman, infrared and magnetic properties of [NH2NH3][M(HCOO)3] (HyM) compounds (M = Mn, Zn, Fe). Our results show that synthesis from methanol solution leads to perovskite polymorphs while that from 1-methyl-2-pyrrolidinone or its mixture with methanol allows obtaining chiral polymorphs. Perovskite HyFe, chiral HyFe and chiral HyMn undergo phase transitions at 347, 336 and 296 K, respectively, with symmetry changes from Pnma to Pna21, P63 to P212121 and P63 to P21. X-ray diffraction and Raman studies show that the phase transitions are governed by dynamics of the hydrazinium ions. Low-temperature magnetic studies show that these compounds exhibit magnetic ordering below 9-12.5 K. Since the low-temperature structures of chiral HyMn and perovskite HyFe are polar, these compounds are possible multiferroic materials. We also report high-pressure Raman scattering studies of chiral and perovskite HyZn, which show much larger stiffness of the latter phase. These studies also show that the ambient pressure polar phases are stable up to at least 1.4 and 4.1 GPa for the chiral and perovskite phase, respectively. Between 1.4 and 2.0 GPa (for chiral HyZn) and 4.1 and 5.2 GPa (for perovskite HyZn) pressure-induced transitions are observed associated with changes in the zinc-formate framework. Strong broadening of Raman bands and the decrease in their number for the high-pressure phase of chiral HyZn suggest that this phase is disordered and has higher symmetry than the ambient pressure one.

  18. Impaired muscarinic type 3 (M3) receptor/PKC and PKA pathways in islets from MSG-obese rats.

    PubMed

    Ribeiro, Rosane Aparecida; Balbo, Sandra Lucinei; Roma, Letícia Prates; Camargo, Rafael Ludemann; Barella, Luiz Felipe; Vanzela, Emerielle Cristine; de Freitas Mathias, Paulo Cesar; Carneiro, Everardo Magalhães; Boschero, Antonio Carlos; Bonfleur, Maria Lúcia

    2013-07-01

    Monosodium glutamate-obese rats are glucose intolerant and insulin resistant. Their pancreatic islets secrete more insulin at increasing glucose concentrations, despite the possible imbalance in the autonomic nervous system of these rats. Here, we investigate the involvement of the cholinergic/protein kinase (PK)-C and PKA pathways in MSG β-cell function. Male newborn Wistar rats received a subcutaneous injection of MSG (4 g/kg body weight (BW)) or hyperosmotic saline solution during the first 5 days of life. At 90 days of life, plasma parameters, islet static insulin secretion and protein expression were analyzed. Monosodium glutamate rats presented lower body weight and decreased nasoanal length, but had higher body fat depots, glucose intolerance, hyperinsulinemia and hypertrigliceridemia. Their pancreatic islets secreted more insulin in the presence of increasing glucose concentrations with no modifications in the islet-protein content of the glucose-sensing proteins: the glucose transporter (GLUT)-2 and glycokinase. However, MSG islets presented a lower secretory capacity at 40 mM K(+) (P < 0.05). The MSG group also released less insulin in response to 100 μM carbachol, 10 μM forskolin and 1 mM 3-isobutyl-1-methyl-xantine (P < 0.05, P < 0.0001 and P < 0.01). These effects may be associated with a the decrease of 46 % in the acetylcholine muscarinic type 3 (M3) receptor, and a reduction of 64 % in PKCα and 36 % in PKAα protein expressions in MSG islets. Our data suggest that MSG islets, whilst showing a compensatory increase in glucose-induced insulin release, demonstrate decreased islet M3/PKC and adenylate cyclase/PKA activation, possibly predisposing these prediabetic rodents to the early development of β-cell dysfunction.

  19. Characterization and thermal behavior of PrMO{sub 3} (M = Co or Ni) ceramic materials obtained from gelatin

    SciTech Connect

    Aquino, F.M.; Melo, D.M.A.; Pimentel, P.M.; Braga, R.M.; Melo, M.A.F.; Martinelli, A.E.; Costa, A.F.

    2012-09-15

    Graphical abstract: The micrograph in figure shows sample calcined at temperature 900 °C. The sample exhibits morphology with considerable porosity and the formation of agglomerated nanometric particles. Gelatin provides the system with a large amount of organic matter, which is then removed during calcinations, favoring the appearance of pores in the material. Highlights: ► Oxides with PrNiO{sub 3} and PrCoO{sub 3} were prepared by new method synthesis. ► The gelatin, through its carboxylate groups and amine, is an efficient director. ► The obtained materials have magnetic properties and application in catalysis. ► The decomposition kinetic study of bonding groups of gelatin with metallic ions that takes part in the synthesis of PrMO{sub 3}. -- Abstract: Metal oxides with perovskite-type structure have attracted considerable interest in recent years due to their magnetic and electrical properties, as well as their catalytic activity. In this study, oxides with PrNiO{sub 3} and PrCoO{sub 3} composition were prepared by using gelatin powder as a precursor agent for its use as a catalyst. The powders obtained were calcined at 700 °C and 900 °C and characterized using the X-ray diffraction, thermal analysis (thermogravimetry and differential thermal analysis), infrared spectroscopy, temperature programed reduction and scanning electron microscopy techniques. Thermogravimetric data using the non-isothermal kinetic models of Flynn and Wall and “Model-free Kinetics” were used to determine the activation energy to study the decomposition kinetics of the ligand groups with system's metallic ions that takes part in the synthesis of PrMO{sub 3} (M = Ni or Co).

  20. Quantity of Soil Organic Matter in the Upper 3 m of Soil in the Northern Circumpolar Permafrost Region

    NASA Astrophysics Data System (ADS)

    Hugelius, G.; Tarnocai, C.

    2012-12-01

    The current estimate for soil organic carbon (SOC) quantity in the northern circumpolar permafrost region (Tarnocai et al., 2009) is 191 Pg for topsoil (0-30 cm depth), 496 Pg for the upper 100 cm of soil and SOC mass to 300 cm soil depth is estimated to be 1024 Pg. In addition, storage in deeper (> 300 cm) Yedoma deposits (407 Pg) and deltaic deposits (241 Pg) brings the total estimate to 1672 Pg, of which 1466 Pg is stored in perennially frozen ground. The estimate for 0-1 m depth SOC mass is based on the Northern Circumpolar Soil Carbon Database (NCSCD), a geospatial database which links 1647 pedons from the northern permafrost regions to several digitized regional/national soil maps with a combined circumpolar coverage. This database has recently been published online and the data is available in several different file formats, including gridded files with different spatial resolutions. Files adapted for use in GIS or modeling applications (shape-files, TIFF-rasters and NetCDF files) are available for separate regions or with merged circumpolar coverage. Estimates for the 0-30 cm and 0-100 cm depth ranges based on the NCSCD are unlikely to be significantly changed or refined in the coming years. However, the emergence of high quality geospatial datasets with circumpolar coverage as well as applications of spatially distributed regression/kriging techniques in periglacial environments (e.g. Mishra and Riley, 2012) point towards complementary approaches that may significantly increase our knowledge of circumpolar SOC distribution. The present estimates of SOC mass in the 0-300 cm depth range is based on very limited field data (46 Canadian pedons), is accorded low to very low confidence and is not included in the spatially distributed NCSCD (Tarnocai et al., 2009). However, a compilation of additional pedon data is underway and an updated version of the NCSCD will be complemented with spatially distributed estimates of 100-200 cm and 200-300 cm depth SOCM based

  1. Expression of transforming growth factor-beta 2 and beta 3 mRNAs and proteins in the developing chicken embryo.

    PubMed

    Jakowlew, S B; Ciment, G; Tuan, R S; Sporn, M B; Roberts, A B

    1994-01-01

    Specific cDNA probes and antibodies for chicken transforming growth factor (TGF)-beta 2 and beta 3 were used to study expression of TGF-beta 2 and beta 3 mRNAs and proteins in the developing chicken embryo. Expression of the mRNAs for both TGF-beta isoforms was detected by day 1.5 of incubation (Hamburger and Hamilton stage 10) by RNA Northern blot analysis and increased with developmental age. Expression of TGF-beta 2 and beta 3 mRNAs was detected in every embryonic tissue examined, with the level of expression of both isoforms being high in heart, brain and muscle and low in kidney and liver. Coordinate unidirectional upregulation of expression of TGF-beta 2 and beta 3 mRNAs occurred in most embryonic tissues with development except the heart, where the steady-state level of expression of TGF-beta 2 mRNA decreased with age, while that of TGF-beta 3 mRNA increased. In situ hybridization analysis detected TGF-beta 2 and beta 3 mRNAs as early as the definitive primitive streak stage (stage 4). During neurulation (stage 10), TGF-beta 2 and beta 3 mRNAs were detected in cells of all three germ layers; TGF-beta 3 mRNA was detected in neurectoderm as well. Following neurulation, TGF-beta 3 mRNA was detected in the neural tube, notochord, ectoderm, endoderm, sclerotome and dermomyotome at stage 16; expression of TGF-beta 2 mRNA was not as prominent as TGF-beta 3 mRNA in these structures. By stage 29, both TGF-beta 2 and beta 3 mRNAs were localized in several tissues including heart, lung, gizzard and feathers. Immunohistochemical staining analysis detected immunoreactive TGF-beta 2 and beta 3 proteins in all three germ layers of stage 4 embryos. Staining for TGF-beta 2 and beta 3 proteins was detected in several cell types and tissues in the early developing embryo frequently in the same locations as TGF-beta 2 and beta 3 mRNAs, with staining for TGF-beta 2 being less intense than TGF-beta 3. However, in some cases, localization of TGF-beta 2 and beta 3 proteins was

  2. A randomised trial comparing combination chemotherapy using mitomycin C, mitozantrone and methotrexate (3M) with vincristine, anthracycline and cyclophosphamide (VAC) in advanced breast cancer.

    PubMed Central

    Powles, T. J.; Jones, A. L.; Judson, I. R.; Hardy, J. R.; Ashley, S. E.

    1991-01-01

    This paper describes a randomised clinical trial in patients with advanced breast cancer, comparing the regimen 3M, mitomycin C 7-8 mg m-2 (day 1), mitozantrone 7-8 mg m-2 (day 1 and 21), methotrexate 35 mg m-2 (day 1 and 21) given on a 42 day cycle with a standard anthracycline containing regimen, VAC, vincristine 1.4 mg m-2 (day 1), anthracycline (adriamycin or epirubicin) 30 mg m-2 (day 1), cyclophosphamide 400 mg m-2 (day 1) given on a 21 day cycle. Of a total of 217 patients, 107 were randomised to 3M and 110 to VAC and a mean of 5.5 courses was given per patient. The overall response rate (complete and partial) was 53% (95% Confidence Limits (CL): 43-62%) for 3M and 49% (CL; 39-58%) for VAC. The response according to sites of metastases was the same for both treatment groups. Symptomatic toxicity including alopecia, neuropathy, vomiting (P less than 0.001) and nausea (P less than 0.01) were significantly less for 3M. Myelosuppression including leucopenia (P less than 0.001) and thrombocytopenia (P less than 0.001) was significantly greater with 3M at day 21, although there was no difference in nadir counts in patients at special risk of myelosuppression and there was no evidence of an increase in infective or bleeding complications. There was no significant difference in the duration of response to 3M (10 months, CL 6-15) and VAC (11 months, CL 7-12), nor in survival (3M, 8 months, CL 6-12; VAC, 10 months, CL 8-12). These results indicate that 3M is as effective as, but has significantly less symptomatic toxicity than, an anthracycline containing regimen for the treatment of advanced breast cancer. PMID:1892775

  3. Transcription Expression and Clinical Significance of Dishevelled-3 mRNA and δ-Catenin mRNA in Pleural Effusions from Patients with Lung Cancer

    PubMed Central

    Li, Xiao-Yan; Liu, Shu-Li; Cha, Na; Zhao, Yu-Jie; Wang, Shao-Cheng; Li, Wei-Nan; Wang, En-Hua; Wu, Guang-Ping

    2012-01-01

    Objective. To evaluate diagnostic utility of Dishevelled-3 (DVL-3) mRNA and δ-catenin mRNA expression in pleural effusions of patients with lung cancer. Methods. DVL-3 mRNA and δ-catenin mRNA levels were assessed by performing RT-PCR on pleural effusion specimens from patients with lung cancer (n = 75) and with lung benign disease (n = 51). Results. The expressions of DVL-3 mRNA and δ-catenin mRNA were significantly higher in malignant than in benign lung disease (P < 0.01) and were obviously higher than cytology in adenocarcinoma (P < 0.01). In single use, DVL-3 mRNA had the highest specificity (94.1%) and PPV (95.7%), whereas δ-catenin mRNA had the highest sensitivity (92.0%) and NPV (88.5%). When combinations of markers were evaluated together, DVL-3 mRNA and δ-catenin mRNA gave a high-diagnostic performance: sensitivity of 100.0%, NPV of 100.0%, and accuracy of 96.0%, respectively. Conclusion. As molecular markers of detecting pleural micrometastasis, DVL-3 mRNA and δ-catenin mRNA are helpful to diagnose the cancer cells in pleural effusions of patients with lung cancer. PMID:22461838

  4. Spacewatch Astrometry of Asteroids and Comets with the Bok 2.3-m and Mayall 4-m Telescopes.

    NASA Astrophysics Data System (ADS)

    Scotti, James V.; McMillan, Robert S.; Larsen, Jeffrey A.

    2014-11-01

    We use the Bok 2.3-m and Mayall 4-m telescopes on Kitt Peak to improve knowledge of the orbits and magnitudes of high priority classes of Near Earth Objects (NEOs) and other small bodies in need of recovery that cannot be reached with the Spacewatch 0.9-m and 1.8-m telescopes. Targets include NEOs with potential close encounters with Earth (Virtual Impactors; VIs), future targets of radar, NEOs previously detected by NEOWISE with orbits or albedos suggesting potential for cometary activity, potential destinations for spacecraft, returning NEOs with hard-won albedos and diameters determined by NEOWISE, and faint Potentially Hazardous Asteroids (PHAs). Notable targets successfully recovered include the Earth Trojan 2010 TK7 and the faint almost-lost VI 2011 BY24 discovered by NEOWISE. Between 2010 June 6 and 2014 July 23 the MPC accepted 1316 lines of astrometry by us with these telescopes on 207 different NEOs including 84 PHAs. We made 343 observations of PHAs with V>=22. Our average arc extension on large PHAs (with H<=17.75) is 184 days, which is 2x longer than the next most effective observing station. Recently with all four telescopes Spacewatch has made 39% of all the observations of PHAs that were fainter than V=22 at the time of measurement. This count is twice that of the next most productive station in that measure. The faintest V magnitude we have observed so far is 24.4 and the smallest solar elongation angle at which we have observed is 46 degrees. Our work with the Mayall and Bok telescopes has been determined by the Minor Planet Center (MPC) to provide "dramatic improvement" to NEO orbits (T. Spahr, 2014 private communication). Support of Spacewatch was/is from JPL subcontract 100319 (2010-2011), NASA/NEOO grants NNG06GJ42G, NNX11AB52G, NNX12AG11G, NNX13AP99G, NNX14AL13G, and NNX14AL14G, the Lunar and Planetary Laboratory, the Brinson Foundation of Chicago, IL, the estates of R. S. Vail and R. L. Waland, and other private donors. We are also indebted

  5. Uncoupling protein-3 mRNA levels are increased in white adipose tissue and skeletal muscle of bezafibrate-treated rats.

    PubMed

    Cabrero, A; Llaverías, G; Roglans, N; Alegret, M; Sánchez, R; Adzet, T; Laguna, J C; Vázquez, M

    1999-07-05

    Fibrates are hypolipidemic drugs that are also able to improve glucose tolerance in animals and diabetic patients through an unknown mechanism. Since uncoupling proteins (UCP) seem to play an important role in the pathogenesis of non-insulin-dependent diabetes mellitus (NIDDM), we examined whether treatment of rats with bezafibrate for 3, 7, or 15 days modified UCP mRNA levels. Using RT-PCR, we observed a weak ectopic expression of UCP-1 and a 2-fold increase in UCP-3 mRNA levels in white adipose tissue after 7 and 15 days of treatment. Moreover, bezafibrate administration caused a 1. 7-fold induction in UCP-3 mRNA levels in skeletal muscle on day 7. Since UCP-3 mRNA levels are reduced in skeletal muscle of diabetic patients, this effect may be involved in the improvement of insulin sensitivity caused by bezafibrate in NIDDM.

  6. Human Epidermal Growth Factor Receptor-3 mRNA Expression as a Prognostic Marker for Invasive Duct Carcinoma not Otherwise Specified

    PubMed Central

    Hammoda, Ghada Ezat; El-Hefnawy, Sally Mohammed; Abdallah, Rania Abdallah

    2017-01-01

    Introduction Breast cancer is the most common cancer in women and the Erythroblastosis Oncogene B(ErbB) receptor family holds crucial role in its pathogenesis. Human Epidermal Growth Factor Receptor 3 (HER-3) gene over expression in breast tissue has been associated with aggressive clinical behaviour and bad prognosis. Aim To evaluate HER-3 mRNA expression level as a prognostic marker for breast cancer and to correlate its level with other established prognostic parameters. Materials and Methods This study was carried out on specimens of 100 cases that were divided into 40 patients presented with fibroadenoma and 60 patients presented with Invasive Ductal Carcinoma (IDC) not otherwise specified and underwent modified radical mastectomy. All specimens were investigated for HER-2/neu, ER and PR expression by Immunohistochemistry (IHC) and quantitative assay of HER-3 mRNA expression using real time PCR technique. Results There was a significant high HER3 mRNA level in carcinoma cases compared to fibroadenoma. In malignant cases, HER3 mRNA level was significantly associated with advanced T stage, advanced N stage, number of positive lymph nodes, large tumour size and cases associated with an adjacent in situ component. Moreover, HER-3 mRNA level was of highest values in Her-2/neu positive group followed by triple negative cases with the lowest level in luminal group (p<0.05). Conclusion HER-3 gene is upregulated in IDC especially those carrying poor prognostic features. HER-3 mRNA level may identify a subset of patients with a poor prognosis, and who could undergo further evaluation for the efficacy of HER3 targeted anticancer therapy. PMID:28384967

  7. Carbon-carbon cylinder block

    NASA Technical Reports Server (NTRS)

    Ransone, Philip O. (Inventor)

    1998-01-01

    A lightweight cylinder block composed of carbon-carbon is disclosed. The use of carbon-carbon over conventional materials, such as cast iron or aluminum, reduces the weight of the cylinder block and improves thermal efficiency of the internal combustion reciprocating engine. Due to the negligible coefficient of thermal expansion and unique strength at elevated temperatures of carbon-carbon, the piston-to-cylinder wall clearance can be small, especially when the carbon-carbon cylinder block is used in conjunction with a carbon-carbon piston. Use of the carbon-carbon cylinder block has the effect of reducing the weight of other reciprocating engine components allowing the piston to run at higher speeds and improving specific engine performance.

  8. Unique expression features of cancer-type organic anion transporting polypeptide 1B3 mRNA expression in human colon and lung cancers

    PubMed Central

    2014-01-01

    Background We have previously identified the cancer-type organic anion transporting polypeptide 1B3 (Ct-OATP1B3) mRNA in several human colon and lung cancer tissues. Ct-OATP1B3 is a variant of the liver-type OATP1B3 (Lt-OATP1B3) mRNA, which is a hepatocyte plasma membrane transporter with broad substrate specificity. However, in cancer tissues, both the detailed characteristics of Ct-OATP1B3 mRNA expression and its biological functions remain unclear. With this point in mind, we sought to characterize Ct-OATP1B3 mRNA expression in colon and lung cancer tissues. In addition, we attempted to obtain functional implication of Ct-OATP1B3 in cancer cells. Methods Matched pairs of cancer and normal tissues were collected from 39 colon cancer and 28 lung cancer patients. The OATP1B3 mRNA expression levels in each of these tissues were separately determined by quantitative real-time polymerase chain reaction. Mann–Whitney U test and Fisher’s exact test were used in statistical analysis. The Ct-OATP1B3 functional expression in colon cancer cells was then examined by Western blotting and transport analyses. Results Ct-OATP1B3 mRNA, but not Lt-OATP1B3 mRNA, was abundantly expressed in colon cancer tissues at a higher detection frequency (87.2%) than that of the adjacent normal tissues (2.6%). Furthermore, it was found that Ct-OATP1B3 mRNA expression was often detected in early colon cancer stages (88.9%, n = 18), and that its expression was associated with well-differentiated colon cancer statuses. On the other hand, Ct-OATP1B3 mRNA also showed a predominant and cancer-associated expression profile in lung tissues, although at frequencies and expression levels that were lower than those obtained from colon cancer. As for attempts to clarify the Ct-OATP1B3 functions, neither protein expression nor transport activity could be observed in any of the cell lines examined. Conclusions Based on the unique characteristics of the Ct-OATP1B3 mRNA expression profile identified in

  9. Carbon Smackdown: Carbon Capture

    SciTech Connect

    Jeffrey Long

    2010-07-12

    In this July 9, 2010 Berkeley Lab summer lecture, Lab scientists Jeff Long of the Materials Sciences and Nancy Brown of the Environmental Energy Technologies Division discuss their efforts to fight climate change by capturing carbon from the flue gas of power plants, as well as directly from the air

  10. Carbon Smackdown: Carbon Capture

    ScienceCinema

    Jeffrey Long

    2016-07-12

    In this July 9, 2010 Berkeley Lab summer lecture, Lab scientists Jeff Long of the Materials Sciences and Nancy Brown of the Environmental Energy Technologies Division discuss their efforts to fight climate change by capturing carbon from the flue gas of power plants, as well as directly from the air

  11. Precipitation Hardening of Laser-Surfaced Layer of Maraging Alloy at the Surface of Steel 3Kh3M3F

    NASA Astrophysics Data System (ADS)

    Stavrev, D. S.; Shcherbakov, V. S.

    2016-09-01

    The structure and fracture behavior of a layer of maraging alloy deposited by laser surfacing on steel 3Kh3M3F is studied in the initial condition and after precipitation hardening at 550 and 600°C. Microhardness is measured in layer cross sections, and fractures after surfacing and aging are analyzed in an electron microscope.

  12. Isothiocyanate-functionalized bifunctional chelates and fac-[MI(CO)3]+ (M = Re, 99mTc) complexes for targeting uPAR in prostate cancer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Developing strategies to rapidly incorporate the fac-[MI(CO)3]+ (M = Re, 99mTc) core into biological targeting vectors is a growing realm in radiopharmaceutical development. This work presents the preparation of a novel isothiocyanate-functionalized bifunctional chelate based on 2,2´-dipicolylamine ...

  13. The hydrazide/hydrazone click reaction as a biomolecule labeling strategy for M(CO)3 (M = Re, (99m)Tc) radiopharmaceuticals.

    PubMed

    Ganguly, Tanushree; Kasten, Benjamin B; Bučar, Dejan-Krešimir; MacGillivray, Leonard R; Berkman, Clifford E; Benny, Paul D

    2011-12-28

    Facile reactivity of hydrazides and aldehydes was explored as potential coupling partners for incorporation into M(CO)(3) (M = Re, (99m)Tc) based radiopharmaceuticals. Both 'click, then chelate' and 'prelabel, then click' synthetic routes produced identical products in high yields and lacked metal-hydrazide/-hydrazone interactions, highlighting the potential of this click strategy.

  14. Influence of Functionalized Pyridine Ligands on the Radio/Chemical Behavior of [MI(CO)3]+ (M = Re and 99mTc) 2 + 1 Complexes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While a number of chelate strategies have been developed for the organometallic precursor fac-[M (OH2)3(CO)3]+ (M = Re, 99mTc), a unique challenge has been to improve the overall function and performance of these complexes for in vivo and in vitro applications. Since its synthesis, the fac-[M (CO)3]...

  15. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - PHYSICAL REMOVAL OF MICROBIOLOGICAL & PARTICULATE CONTAMINANTS IN DRINKING WATER: US FILTER 3M10C MICROFILTRATION MEMBRANE SYSTEM AT CHULA VISTA, CALIFORNIA

    EPA Science Inventory

    Verification testing of the US Filter 3M10C membrane system was conducted over a 44-day test period at the Aqua 2000 Research Center in Chula Vista, California. The test period extended from July 24, 2002 to September 5, 2002. The source water was a blend of Colorado River and ...

  16. Comparative in vitro release and clinical pharmacokinetics of leuprolide from Luphere 3M Depot, a 3-month release formulation of leuprolide acetate.

    PubMed

    Park, Sunghoon; Kim, Dong-Hwan; Kim, Yoon; Park, Jeong Hwa; Lee, MinSeok; Song, Im-Sook; Shim, Chang-Koo

    2017-03-01

    A 3-month depot formulation of leuprolide acetate (Luphere 3M Depot) with a mean microsphere diameter of 22.3 μm was prepared aseptically by spray-drying glacial acetic acid solution of the drug and polylactic acid, and lyophilization in a d-mannitol solution. The encapsulation efficiency and loading content of the drug in the Luphere 3M Depot were 94.7% and 9.92% (w/w), respectively. The in vitro release of leuprolide from the depot was substantially delayed and the release profile was similar to that of Lucrin Depot (Abbott Korea, Korea). The safety and pharmacokinetics of leuprolide were investigated over a period of 42 days in 20 prostate cancer patients following a subcutaneous injection of Luphere 3M or Lucrin Depot suspensions (leuprolide acetate dose of 11.25 mg) in a multi-center, randomized, single dose, parallel study. Both formulations were well tolerated by the patients and no serious adverse effects were observed during and after the study. No significant differences were observed in the maximum serum concentration (Cmax) and area under the curve (AUClast) of leuprolide between the two formulations. The results suggest comparable safety and efficacy profiles of Luphere 3M Depot and Lucrin Depot in clinical situations.

  17. Lactuside B decreases aquaporin-4 and caspase-3 mRNA expression in the hippocampus and striatum following cerebral ischaemia-reperfusion injury in rats

    PubMed Central

    LI, PING-FA; ZHAN, HE-QIN; LI, SHENG-YING; LIU, RUI-LI; YAN, FU-LIN; CUI, TAI-ZHEN; YANG, YU-PING; LI, PENG; WANG, XIN-YAO

    2014-01-01

    This study aimed to investigate the effects of lactuside B (LB) on aquaporin-4 (AQP4) and caspase-3 mRNA expression in the hippocampus and the striatum following cerebral ischaemia-reperfusion (I/R) injury in rats. Cerebral I/R injury was established in Sprague-Dawley rats by occluding the middle cerebral artery for 2 h and then inducing reperfusion. Rats in the I/R + LB groups were treated with various doses of LB following reperfusion. Neurological deficit scores and brain water content were obtained to determine the pharmacodynamics of LB. Reverse transcription polymerase chain reaction was performed to determine the expression levels of AQP4 and caspase-3 mRNA in the hippocampus and the striatum. The results of the present study indicate that LB decreased the neurological deficit scores and the brain water content. In the hippocampus, AQP4 and caspase-3 mRNA expression levels were significantly downregulated in the I/R + LB groups at 24 and 72 h following drug administration, compared with those in the I/R group (P<0.05). In the striatum, LB was also shown to significantly reduce AQP4 and caspase-3 mRNA expression levels at 24 and 72 h following drug administration, compared with those in the I/R group (P<0.05). The effects became stronger as the LB dose was increased. The most significant reductions in AQP4 and caspase-3 mRNA expression were noted in the I/R + LB 25 mg/kg and I/R + LB 50 mg/kg groups at 72 h following drug administration. The results of the present study show that LB is capable of significantly downregulating AQP4 and caspase-3 mRNA expression in the hippocampus and striatum following cerebral I/R injury in rats. The mechanism by which LB improved ischaemic brain injury may be associated with changes in AQP4 and caspase-3 mRNA expression in the hippocampus and the striatum. PMID:24520266

  18. Effects of the Yeast RNA-Binding Protein Whi3 on the Half-Life and Abundance of CLN3 mRNA and Other Targets

    PubMed Central

    Cai, Ying; Futcher, Bruce

    2013-01-01

    Whi3 is an RNA binding protein known to bind the mRNA of the yeast G1 cyclin gene CLN3. It inhibits CLN3 function, but the mechanism of this inhibition is unclear; in previous studies, Whi3 made no observable difference to CLN3 mRNA levels, translation, or protein abundance. Here, we re-approach this issue using microarrays, RNA-Seq, ribosome profiling, and other methods. By multiple methods, we find that the whi3 mutation causes a small but consistent increase in the abundance of hundreds of mRNAs, including the CLN3 mRNA. The effect on various mRNAs is roughly in proportion to the density of GCAU or UGCAU motifs carried by these mRNAs, which may be a binding site for Whi3. mRNA instability of Whi3 targets may in part depend on a 3′ AU rich element (ARE), AUUUUA. In addition, the whi3 mutation causes a small increase in the translational efficiency of CLN3 mRNA. The increase in CLN3 mRNA half-life and abundance together with the increase in translational efficiency is fully sufficient to explain the small-cell phenotype of whi3 mutants. Under stress conditions, Whi3 becomes a component of P-bodies or stress granules, but Whi3 also acts under non-stress condition, when no P-bodies are visible. We suggest that Whi3 may be a very broadly-acting, but mild, modulator of mRNA stability. In CLN3, Whi3 may bind to the 3′ GCAU motifs to attract the Ccr4-Not complex to promote RNA deadenylation and turnover, and Whi3 may bind to the 5′ GCAU motifs to inhibit translation. PMID:24386402

  19. METC/3M Cooperative Agreement CRADA 94-024 high temperature high pressure filter materials exposure test program. Volume 1, Final report

    SciTech Connect

    1995-06-01

    In conjunction with shakedown, operation, and desulfurization testing at the Morgantown Energy Technology Center (METC) 10 in. Fluid Bed Gasification and Cleanup facility, a series of tests was completed in cooperation with the Minnesota Mining and Manufacturing Company (3M). This cooperative research and development agreement (CRADA) between METC and 3M was to evaluate exposure of 3M SICONEX{trademark} fiber-reinforced ceramic and NEXTEL{trademark} 312 and 550 ceramic fabric materials to a gasifying environment at high temperatures (1000--1100{degree}F) and high pressure (300 psia). Minnesota Mining and Manufacturing Company (3M) provided two 60 mm I.D. {times} 0.5 m SICONEX{trademark} spools and one each of the NEXTEL{trademark} 312 and 550 ceramic fabrics for exposure to coal gas from the METC gasifier. METC installed the materials in a vessel existing in the METC Cleanup Facility and provided process data in exchange for ceramic filter and ash/char characterization. Details of the CRADA are found in CRADA 94-024. This report contains METC`s contribution to CRADA 94-024. Four gasifier runs were conducted over a five month period to accumulate 483 hours of operation. During this time, 2 LayCer{trademark} 70/3 filters were used for filtering the coal gas while the SICONEX{trademark} and NEXTEL{trademark} were exposed along side of the filters. During one 89 hour test, one Laycer{trademark} 70/3 candle was installed with a 3M ceramic composite filter. The face velocity through the candles was maintained nominally at 2.5 ft/min throughout the testing.

  20. Carbon-carbon piston development

    NASA Technical Reports Server (NTRS)

    Gorton, Mark P.

    1994-01-01

    A new piston concept, made of carbon-carbon refractory-composite material, has been developed that overcomes a number of the shortcomings of aluminum pistons. Carbon-carbon material, developed in the early 1960's, is lighter in weight than aluminum, has higher strength and stiffness than aluminum and maintains these properties at temperatures over 2500 F. In addition, carbon-carbon material has a low coefficient of thermal expansion and excellent resistance to thermal shock. An effort, called the Advanced Carbon-Carbon Piston Program was started in 1986 to develop and test carbon-carbon pistons for use in spark ignition engines. The carbon-carbon pistons were designed to be replacements for existing aluminum pistons, using standard piston pin assemblies and using standard rings. Carbon-carbon pistons can potentially enable engines to be more reliable, more efficient and have greater power output. By utilizing the unique characteristics of carbon-carbon material a piston can: (1) have greater resistance to structural damage caused by overheating, lean air-fuel mixture conditions and detonation; (2) be designed to be lighter than an aluminum piston thus, reducing the reciprocating mass of an engine, and (3) be operated in a higher combustion temperature environment without failure.

  1. Expression of Ets-1 and FOXP3 mRNA in CD4(+)CD25 (+) T regulatory cells from patients with systemic lupus erythematosus.

    PubMed

    Xiang, Nan; Li, Xiang-Pei; Li, Xiao-Mei; Wang, Guo-Sheng; Tao, Jin-Hui; Pan, Hai-Feng; Fang, Xuan; Ma, Qian; Yu, Ning

    2014-11-01

    Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with complex genetic predisposing factors involved. Ets-1 transcription factor plays an important role in the suppressive activity of CD4(+)CD25(+) Treg cells and stable expression of FOXP3. To find its potential role in the pathogenesis of SLE, we investigate the mRNA expression of Ets-1 and FOXP3 mRNA in CD4(+)CD25(+) Treg cells from patients with SLE. Real-time transcription-polymerase chain reaction analysis was used to determine the expression of Ets-1 and FOXP3 mRNA in CD4(+)CD25(+) Treg cells from 36 patients with SLE and 18 sex-and-age-matched healthy controls. The Ets-1 mRNA expression level was decreased in patients with SLE [0.225 (0.135, 0.337)] than healthy controls [0.528 (0.303, 0.681)] (P < 0.001). The expression levels of FOXP3 mRNA were lower in SLE patients [0.608 (0.272, 1.164)] than healthy controls [0.919 (0.690, 1.223)], but the difference was not significant (P = 0.106). Significant reduction in Ets-1 and FOXP3 expression was also found in new-onset SLE subgroup when compared with healthy controls (P < 0.001). The level of Ets-1 and FOXP3 mRNA was not significantly different in hyperactive and lower active SLE group when compared with inactive SLE group, respectively (P > 0.05). There were no significant differences between SLE with lupus nephritis (LN) and SLE without LN either (P > 0.05). Associations of Ets-1 and FOXP3 mRNA expression levels with major clinical and laboratory parameters of SLE patients were also analyzed. However, no significant association was found. Significant positive correlation was found between Ets-1 and FOXP3 mRNA expression in CD4(+)CD25(+) Treg cells from SLE patients (r = 0.698, P < 0.001). Our results found that the expression levels of Ets-1 mRNA were decreased in SLE patients and Ets-1 expression was positively correlated with the expression of FOXP3. It indicated that Ets-1 may play an important role in the stable expression of FOXP3 in

  2. Intergrowth of hexagonal tungsten bronze and perovskite-like structures: The oxides ACu 3M7O 21 ( A = K, Rb, Cs, TI; M = Nb, Ta)

    NASA Astrophysics Data System (ADS)

    Benmoussa, A.; Groult, D.; Studer, F.; Raveau, B.

    1982-02-01

    Seven oxides ACu 3M7O 21 have been isolated with A = K, Rb, Tl, Cs for M = Ta and A = K, Rb, Cs for M = Nb. These phases are orthorhombic: a ⋍ 28 Å, b ⋍ 7.50 Å, and c ⋍ 7.55 Å, probable space group Cmmm. Their structure has been established from an X-ray diffraction study and from high-resolution microscopy observations. The structure consists of an intergrowth of single hexagonal tungsten bronze AM3O 9 slices and double distorted perovskite Cu 3M4O 12 slabs ( M = Nb, Ta) in which copper has a square coordination. The host lattice of these compounds can be considered as the member " n = 1; n' = 2" of a series of intergrowths corresponding to the formulation | M3O 9| Hn| M2O 6| Pn' .

  3. Structural investigations of Sb2O3-M2O (M=Li, Na or K) glasses by the mean of thermal and elastics characterization

    NASA Astrophysics Data System (ADS)

    Soltani, M. T.; Haddad, S.; Ouennes, K.; Boulegroun, A.; Poulain, M.

    2012-09-01

    By using classical routes (melting - casting), glasses synthesized in silica crucibles were obtained in the combination of binary systems Sb2O3-M2CO3 (M=Li, Na and K). Ultrasonic's velocities were carried out by pulse echo method to determine the elastics parameters, such as elastic modules (E, G, K, L) and other related parameters (Poisson's ration, acoustic impedance, Debye temperature). Other physical properties were measured, such as density and characteristic temperatures. Influence of composition on these physico-chemical properties is discussed. A quantitative analysis of thermal analysis, free volume, elastic and mechanical measurements have been carried out to obtain more information about the structure of alkali antimonite glasses and the role of alkali oxides in these no-conventional glasses. These measurements have been made for the first time on these glasses.

  4. Identification of a QTL in Mus musculus for Alcohol Preference, Withdrawal, and Ap3m2 Expression Using Integrative Functional Genomics and Precision Genetics

    PubMed Central

    Bubier, Jason A.; Jay, Jeremy J.; Baker, Christopher L.; Bergeson, Susan E.; Ohno, Hiroshi; Metten, Pamela; Crabbe, John C.; Chesler, Elissa J.

    2014-01-01

    Extensive genetic and genomic studies of the relationship between alcohol drinking preference and withdrawal severity have been performed using animal models. Data from multiple such publications and public data resources have been incorporated in the GeneWeaver database with >60,000 gene sets including 285 alcohol withdrawal and preference-related gene sets. Among these are evidence for positional candidates regulating these behaviors in overlapping quantitative trait loci (QTL) mapped in distinct mouse populations. Combinatorial integration of functional genomics experimental results revealed a single QTL positional candidate gene in one of the loci common to both preference and withdrawal. Functional validation studies in Ap3m2 knockout mice confirmed these relationships. Genetic validation involves confirming the existence of segregating polymorphisms that could account for the phenotypic effect. By exploiting recent advances in mouse genotyping, sequence, epigenetics, and phylogeny resources, we confirmed that Ap3m2 resides in an appropriately segregating genomic region. We have demonstrated genetic and alcohol-induced regulation of Ap3m2 expression. Although sequence analysis revealed no polymorphisms in the Ap3m2-coding region that could account for all phenotypic differences, there are several upstream SNPs that could. We have identified one of these to be an H3K4me3 site that exhibits strain differences in methylation. Thus, by making cross-species functional genomics readily computable we identified a common QTL candidate for two related bio-behavioral processes via functional evidence and demonstrate sufficiency of the genetic locus as a source of variation underlying two traits. PMID:24923803

  5. Regulation of interleukin 3 mRNA expression in mast cells occurs at the posttranscriptional level and is mediated by calcium ions

    SciTech Connect

    Wodnar-Filipowicz, A.; Moroni, C. )

    1990-01-01

    Interleukin 3 (IL-3) is transiently produced by murine bone marrow-derived mast cells in response to antigen stimulation of the high-affinity immunoglobulin E receptors. The authors have studied the postreceptor signaling pathways involved in regulating expression of the IL-3 gene in the murine mass cell PB-3c. Large amounts of IL-3 mRNA accumulated after exposure of cells to calcium ionophore A23187, a reagent that increases intracellular Ca{sup 2+}. Phorbol 12-myristate 13-acetate, which stimulates protein kinase C, did not induce IL-3 mRNA accumulation, although it did potentiate the effect of A23187. Nuclear run-on analysis showed that the IL-3 gene is constitutively transcribed in unstimulated cells and that treatment with A23187 and/or phorbol ester has no influence on its transcription rate. The effect of A23187 was found to be due to stabilization of the IL-3 mRNA. In cells maintained in the presence of A23187 the IL-3 mRNA was stable during 3 hr of incubation with actinomycin D, whereas removal of A23187 under the same conditions resulted in rapid degradation of the mRNA. These results indicate that control of expression of the IL-3 gene in mast cells is primarily at the posttranscriptional level and that the Ca{sup 2+}-dependent signal-transduction pathway plays an important role in this process. Synthesis of granulocyte/macrophage colony-stimulating factor mRNA in response to A23187 and phorbol ester was found to be subject to both transcriptional and posttranscriptional regulation.

  6. Identification of a QTL in Mus musculus for alcohol preference, withdrawal, and Ap3m2 expression using integrative functional genomics and precision genetics.

    PubMed

    Bubier, Jason A; Jay, Jeremy J; Baker, Christopher L; Bergeson, Susan E; Ohno, Hiroshi; Metten, Pamela; Crabbe, John C; Chesler, Elissa J

    2014-08-01

    Extensive genetic and genomic studies of the relationship between alcohol drinking preference and withdrawal severity have been performed using animal models. Data from multiple such publications and public data resources have been incorporated in the GeneWeaver database with >60,000 gene sets including 285 alcohol withdrawal and preference-related gene sets. Among these are evidence for positional candidates regulating these behaviors in overlapping quantitative trait loci (QTL) mapped in distinct mouse populations. Combinatorial integration of functional genomics experimental results revealed a single QTL positional candidate gene in one of the loci common to both preference and withdrawal. Functional validation studies in Ap3m2 knockout mice confirmed these relationships. Genetic validation involves confirming the existence of segregating polymorphisms that could account for the phenotypic effect. By exploiting recent advances in mouse genotyping, sequence, epigenetics, and phylogeny resources, we confirmed that Ap3m2 resides in an appropriately segregating genomic region. We have demonstrated genetic and alcohol-induced regulation of Ap3m2 expression. Although sequence analysis revealed no polymorphisms in the Ap3m2-coding region that could account for all phenotypic differences, there are several upstream SNPs that could. We have identified one of these to be an H3K4me3 site that exhibits strain differences in methylation. Thus, by making cross-species functional genomics readily computable we identified a common QTL candidate for two related bio-behavioral processes via functional evidence and demonstrate sufficiency of the genetic locus as a source of variation underlying two traits.

  7. Ferroelectric and magnetic properties of Aurivillius Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} thin films

    SciTech Connect

    Jia, Tingting Kimura, Hideo; Cheng, Zhenxiang; Zhao, Hongyang

    2015-11-15

    Aurivillius Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} (m = 4, 5, 6) thin films have been deposited by a pulsed laser deposition system. The x-ray diffraction patterns indicate the formation of orthorhombic phase. The remanent polarization (2P{sub r}) of Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} thin films is decreased with the m-number. Positive-up-negative-down measurements indicate the presence of ferroelectric (FE) polarization in as-obtained thin films. Piezoresponse force microscopy investigations confirm the existence of FE domains and the switchable polarization. Weak magnetic moment is detected in the Aurivillius films at room temperature. The present work suggests the possibility of Aurivillius Bi{sub m+1}Ti{sub 3}Fe{sub m−3}O{sub 3m+3} (m = 4, 5, 6) materials as potential room-temperature multiferroics.

  8. Carbonized asphaltene-based carbon-carbon fiber composites

    DOEpatents

    Bohnert, George; Lula, James; Bowen, III, Daniel E.

    2016-12-27

    A method of making a carbon binder-reinforced carbon fiber composite is provided using carbonized asphaltenes as the carbon binder. Combinations of carbon fiber and asphaltenes are also provided, along with the resulting composites and articles of manufacture.

  9. Carbon-carbon composites

    NASA Technical Reports Server (NTRS)

    Maahs, Howard G.

    1992-01-01

    The current applications of C-C composites extend to aircraft brakes, rocket nozzles, missile nosetips, and leading edges of the Space Shuttle. More advanced, secondary and even primary structure applications in cyclic, high-temperature oxidizing environments depend on effective oxidation protection for repeated missions. Accounts are presently given of state-of-the-art methods in substrate fabrication, carbon deposition, and SiC and Si3N4 protective coatings. Attention is given to current levels of high temperature oxidation protection for various mission and vehicle types, as well as to performance projections for C-C composites used by a representative National Aerospace Plane airframe structure. Future technology requirements in C-C composites are projected.

  10. [Effect of Zhuangyao Jianshen Wan (ZYJCW) on P2X1 and P2X3 mRNA expressions in rats with diuresis caused by kidney deficiency].

    PubMed

    Chen, Jia-yi; Jiang, Wei-wen; He, Feng-lei; Mo, Guo-qiang; Guo, Zhong-hui; Wang, Xiao-dan; Wu, Qing-he; Cao, Hong-yin

    2015-08-01

    To investigate the urination-reducing effect and mechanism of Zhuangyao Jianshen Wan (ZYJCW). In this study, SI rats were subcutaneously injected with 150 mg · kg(-1) dose of D-galactose to prepare the sub-acute aging model and randomly divided into the model group, the Suoquan Wan group (1.17 g · kg(-1) · d(-1)), and ZYJCW high, medium and low dose groups (2.39, 1.20, 0.60 g · kg(-1) · d(-1)) , with normal rats in the blank group. They were continuously administered with drugs for eight weeks. The metabolic cage method was adopted to measure the 24 h urine volume and 5 h water load urine volume in rats. The automatic biochemistry analyzer was adopted to detect urine concentrations of Na+, Cl-, K+. The ELISA method was used to determine serum aldosterone (ALD) and antidiuretic hormone (ADH). The changes in P2X1 and P2X3 mRNA expressions in bladder tissues of rats were detected by RT-PCR. According to the results, both ZYJCW high and medium dose groups showed significant down-regulations in 24 h urine volume and 5 h water load urine volume in (P <0.05, P <0.01), declines in Na+ and Cl- concentrations in urine (P <0.01), notable rises in plasma ALD and ADH contents (P <0.05, P <0.01) and remarkable down-regulations in the P2X1 and P2X3 mRNA expressions in bladder tissues (P <0.01). The ZYJCW low dose group revealed obvious reductions in Na+ and Cl- concentrations in urine (P <0.01). The results indicated that ZYJCW may show the urination-reducing effect by down-regulating the P2X1 and P2X3 mRNA expressions in bladder tissues of rats with diuresis caused by kidney deficiency.

  11. Design of a head phantom produced on a 3D rapid prototyping printer and comparison with a RANDO and 3M lucite head phantom in eye dosimetry applications.

    PubMed

    Homolka, Peter; Figl, Michael; Wartak, Andreas; Glanzer, Mathias; Dünkelmeyer, Martina; Hojreh, Azadeh; Hummel, Johann

    2017-04-21

    An anthropomorphic head phantom including eye inserts allowing placement of TLDs 3 mm below the cornea has been produced on a 3D printer using a photo-cured acrylic resin to best allow tissue equivalence. Thus Hp(3) can be determined in radiological and interventional photon radiation fields. Eye doses and doses to the forehead have been compared to an Alderson RANDO head and a 3M Lucite skull phantom in terms of surface dose per incident air kerma for frontal irradiation since the commercial phantoms do not allow placement of TLDs 3 mm below the corneal surface. A comparison of dose reduction factors (DRFs) of a common lead glasses model has also been performed. Eye dose per incident air kerma were comparable between all three phantoms (printed phantom: 1.40, standard error (SE) 0.04; RANDO: 1.36, SE 0.03; 3M: 1.37, SE 0.03). Doses to the forehead were identical to eye surface doses for the printed phantom and the RANDO head (ratio 1.00 SE 0.04, and 0.99 SE 0.03, respectively). In the 3M Lucite skull phantom dose on the forehead was 15% lower than dose to the eyes attributable to phantom properties. DRF of a sport frame style leaded glasses model with 0.75 mm lead equivalence measured were 6.8 SE 0.5, 9.3 SE 0.4 and 10.5 SE 0.5 for the RANDO head, the printed phantom, and the 3M Lucite head phantom, respectively, for frontal irradiation. A comparison of doses measured in 3 mm depth and on the surface of the eyes in the printed phantom revealed no difference larger than standard errors from TLD dosimetry. 3D printing offers an interesting opportunity for phantom design with increasing potential as printers allowing combinations of tissue substitutes will become available. Variations between phantoms may provide a useful indication of uncertainty budgets when using phantom measurements to estimate individual personnel doses.

  12. Design of a head phantom produced on a 3D rapid prototyping printer and comparison with a RANDO and 3M lucite head phantom in eye dosimetry applications

    NASA Astrophysics Data System (ADS)

    Homolka, Peter; Figl, Michael; Wartak, Andreas; Glanzer, Mathias; Dünkelmeyer, Martina; Hojreh, Azadeh; Hummel, Johann

    2017-04-01

    An anthropomorphic head phantom including eye inserts allowing placement of TLDs 3 mm below the cornea has been produced on a 3D printer using a photo-cured acrylic resin to best allow tissue equivalence. Thus Hp(3) can be determined in radiological and interventional photon radiation fields. Eye doses and doses to the forehead have been compared to an Alderson RANDO head and a 3M Lucite skull phantom in terms of surface dose per incident air kerma for frontal irradiation since the commercial phantoms do not allow placement of TLDs 3 mm below the corneal surface. A comparison of dose reduction factors (DRFs) of a common lead glasses model has also been performed. Eye dose per incident air kerma were comparable between all three phantoms (printed phantom: 1.40, standard error (SE) 0.04; RANDO: 1.36, SE 0.03; 3M: 1.37, SE 0.03). Doses to the forehead were identical to eye surface doses for the printed phantom and the RANDO head (ratio 1.00 SE 0.04, and 0.99 SE 0.03, respectively). In the 3M Lucite skull phantom dose on the forehead was 15% lower than dose to the eyes attributable to phantom properties. DRF of a sport frame style leaded glasses model with 0.75 mm lead equivalence measured were 6.8 SE 0.5, 9.3 SE 0.4 and 10.5 SE 0.5 for the RANDO head, the printed phantom, and the 3M Lucite head phantom, respectively, for frontal irradiation. A comparison of doses measured in 3 mm depth and on the surface of the eyes in the printed phantom revealed no difference larger than standard errors from TLD dosimetry. 3D printing offers an interesting opportunity for phantom design with increasing potential as printers allowing combinations of tissue substitutes will become available. Variations between phantoms may provide a useful indication of uncertainty budgets when using phantom measurements to estimate individual personnel doses.

  13. Carbon-Carbon Piston Architectures

    NASA Technical Reports Server (NTRS)

    Rivers, H. Kevin (Inventor); Ransone, Philip O. (Inventor); Northam, G. Burton (Inventor); Schwind, Francis A. (Inventor)

    1999-01-01

    An improved structure for carbon-carbon composite piston architectures consists of replacing the knitted fiber, three-dimensional piston preform architecture described in U.S. Pat. No. 4.909,133 (Taylor et al.) with a two-dimensional lay-up or molding of carbon fiber fabric or tape. Initially. the carbon fabric or tape layers are prepregged with carbonaceous organic resins and/or pitches and are laid up or molded about a mandrel. to form a carbon-fiber reinforced organic-matrix composite part shaped like a "U" channel, a "T"-bar. or a combination of the two. The molded carbon-fiber reinforced organic-matrix composite part is then pyrolized in an inert atmosphere, to convert the organic matrix materials to carbon. At this point, cylindrical piston blanks are cored from the "U" channel, "T"-bar, or combination part. These blanks are then densified by reimpregnation with resins or pitches which are subsequently carbonized. Densification is also be accomplished by direct infiltration with carbon by vapor deposition processes. Once the desired density has been achieved, the piston billets are machined to final piston dimensions; coated with oxidation sealants; and/or coated with a catalyst. When compared to conventional steel or aluminum-alloy pistons, the use of carbon-carbon composite pistons reduces the overall weight of the engine; allows for operation at higher temperatures without a loss of strength; allows for quieter operation; reduces the heat loss; and reduces the level of hydrocarbon emissions.

  14. Carbonate aquifers

    USGS Publications Warehouse

    Cunningham, Kevin J.; Sukop, Michael; Curran, H. Allen

    2012-01-01

    Only limited hydrogeological research has been conducted using ichnology in carbonate aquifer characterization. Regardless, important applications of ichnology to carbonate aquifer characterization include its use to distinguish and delineate depositional cycles, correlate mappable biogenically altered surfaces, identify zones of preferential groundwater flow and paleogroundwater flow, and better understand the origin of ichnofabric-related karst features. Three case studies, which include Pleistocene carbonate rocks of the Biscayne aquifer in southern Florida and Cretaceous carbonate strata of the Edwards–Trinity aquifer system in central Texas, demonstrate that (1) there can be a strong relation between ichnofabrics and groundwater flow in carbonate aquifers and (2) ichnology can offer a useful methodology for carbonate aquifer characterization. In these examples, zones of extremely permeable, ichnofabric-related macroporosity are mappable stratiform geobodies and as such can be represented in groundwater flow and transport simulations.

  15. Structural design of a vertical antenna boresight 18.3 by 18.3-m planar near-field antenna measurement system

    NASA Astrophysics Data System (ADS)

    Sharp, G. R.; Trimarchi, P. A.; Wanhainen, J. S.

    A large very precise near-field planar scanner was proposed for NASA Lewis Research Center. This scanner would permit near-field measurements over a horizontal scan plane measuring 18.3 m by 18.3 m. Large aperture antennas mounted with antenna boresight vertical could be tested up to 60 GHz. When such a large near field scanner is used for pattern testing, the antenna or antenna system under test does not have to be moved. Hence, such antennas and antenna systems can be positioned and supported to simulate configuration in zero g. Thus, very large and heavy machinery that would be needed to accurately move the antennas are avoided. A preliminary investigation was undertaken to address the mechanical design of such a challenging near-field antenna scanner. The configuration, structural design and results of a parametric NASTRAN structural optimization analysis are contained. Further, the resulting design was dynamically analyzed in order to provide resonant frequency information to the scanner mechanical drive system designers. If other large near field scanners of comparable dimensions are to be constructed, the information can be used for design optimization of these also.

  16. Crystal and electronic structure and magnetic properties of divalent europium perovskite oxides EuMO3 (M = Ti, Zr, and Hf): experimental and first-principles approaches.

    PubMed

    Akamatsu, Hirofumi; Fujita, Koji; Hayashi, Hiroyuki; Kawamoto, Takahiro; Kumagai, Yu; Zong, Yanhua; Iwata, Koji; Oba, Fumiyasu; Tanaka, Isao; Tanaka, Katsuhisa

    2012-04-16

    A comparative study of the crystal and electronic structure and magnetism of divalent europium perovskite oxides EuMO(3) (M = Ti, Zr, and Hf) has been performed on the basis of both experimental and theoretical approaches playing complementary roles. The compounds were synthesized via solid-state reactions. EuZrO(3) and EuHfO(3) have an orthorhombic structure with a space group Pbnm at room temperature contrary to EuTiO(3), which is cubic at room temperature. The optical band gaps of EuZrO(3) and EuHfO(3) are found to be about 2.4 and 2.7 eV, respectively, much larger than that of EuTiO(3) (0.8 eV). On the other hand, the present compounds exhibit similar magnetic properties characterized by paramagnetic-antiferromagnetic transitions at around 5 K, spin flop at moderate magnetic fields lower than 1 T, and the antiferromagnetic nearest-neighbor and ferromagnetic next-nearest-neighbor exchange interactions. First-principles calculations based on a hybrid Hartree-Fock density functional approach yield lattice constants, band gaps, and magnetic interactions in good agreement with those obtained experimentally. The band gap excitations are assigned to electronic transitions from the Eu 4f to Mnd states for EuMO(3) (M = Ti, Zr, and Hf and n = 3, 4, and 5, respectively).

  17. The SF3M approach to 3-D photo-reconstruction for non-expert users: application to a gully network

    NASA Astrophysics Data System (ADS)

    Castillo, C.; James, M. R.; Redel-Macías, M. D.; Pérez, R.; Gómez, J. A.

    2015-04-01

    3-D photo-reconstruction (PR) techniques have been successfully used to produce high resolution elevation models for different applications and over different spatial scales. However, innovative approaches are required to overcome some limitations that this technique may present in challenging scenarios. Here, we evaluate SF3M, a new graphical user interface for implementing a complete PR workflow based on freely available software (including external calls to VisualSFM and CloudCompare), in combination with a low-cost survey design for the reconstruction of a several-hundred-meters-long gully network. SF3M provided a semi-automated workflow for 3-D reconstruction requiring ~ 49 h (of which only 17% required operator assistance) for obtaining a final gully network model of > 17 million points over a gully plan area of 4230 m2. We show that a walking itinerary along the gully perimeter using two light-weight automatic cameras (1 s time-lapse mode) and a 6 m-long pole is an efficient method for 3-D monitoring of gullies, at a low cost (about EUR 1000 budget for the field equipment) and time requirements (~ 90 min for image collection). A mean error of 6.9 cm at the ground control points was found, mainly due to model deformations derived from the linear geometry of the gully and residual errors in camera calibration. The straightforward image collection and processing approach can be of great benefit for non-expert users working on gully erosion assessment.

  18. Evaluation of Variants of 3M Peltor ComTAC Tactical Communication and Protection System (TCAPS) Headsets: Measures of Hearing Protection and Auditory Performance

    DTIC Science & Technology

    2013-09-01

    sound source azimuth. With the exception of the bare head condition, a helmet was always worn , and with the exception of the ComTAC III ARC-carbon...lightweight carbon helmets were worn in combination with the ComTAC III ARC headset to measure the difference in their effect on auditory localization ability...the ComTAC III ARC TCAPS is designed to mount on the Ops-Core FAST helmet accessory rail connector system, all TCAPS were evaluated in combination

  19. Expression of nerve growth factor and neurotrophin-3 mRNAs in hippocampal interneurons: morphological characterization, levels of expression, and colocalization of nerve growth factor and neurotrophin-3.

    PubMed

    Pascual, M; Rocamora, N; Acsády, L; Freund, T F; Soriano, E

    1998-05-25

    We have investigated the distribution and morphology of hippocampal interneurons that express the neurotrophins nerve growth factor (NGF) and neurotrophin-3 (NT-3) in the rat. For this study, we combined in situ hybridization for the detection of NGF and NT-3 mRNAs and immunocytochemistry against the calcium-binding proteins parvalbumin (PARV), calretinin (CALR), and calbindin (CALB). Whereas the majority of PARV+ interneurons expressed NGF mRNA, only subsets of CALR- and CALB-immunoreactive interneurons (23% and 24%, respectively) displayed NGF hybridization. Most CALB/NGF+ cells were located in the stratum oriens/alveus of the CA3-CA1 regions, suggesting that they may include the population of CALB+, hippocamposeptal, nonpyramidal neurons. Most of the nonspiny CALR/NGF+ neurons were located within or in the vicinity of the pyramidal layer and had faint CALR immunostaining and stellate, thin dendrites. Regarding the spiny CALR-immunoreactive cells, we found that most of these neurons in the hilus were NGF+, whereas only 59% of displayed NGF hybridization in the stratum lucidum of the CA3 region. A small subset of PARV- and CALR-immunoreactive cells expressed NT-3 mRNA (16% and 13%, respectively). NT-3 message was not found in the large basket cells of the dentate gyrus, whereas the distribution and morphology of CALR/NT-3+ cells were similar to those of nonspiny CALR/NGF+ cells. In fact, double in situ hybridization analysis confirmed that most NT-3+ neurons also expressed NGF mRNA, indicating coexpression of both neurotrophins in subpopulations of PARV+ and CALR+ neurons. Moreover, the level of NGF mRNA expression was higher in PARV+ neurons than in CALR- and CALB-immunoreactive interneurons, whereas NT-3 message was expressed similarly in PARV+ and CALR+ neurons. The present findings show a differential expression of NGF and NT-3 mRNAs in subsets of hippocampal interneurons and suggest that the expression of these transcripts depends on factors intrinsic to

  20. Carbon photonics

    SciTech Connect

    Konov, V I

    2015-11-30

    The properties of new carbon materials (single-crystal and polycrystalline CVD diamond films and wafers, single-wall carbon nanotubes and graphene) and the prospects of their use as optical elements and devices are discussed. (optical elements of laser devices)

  1. Magnetic and Mechanical Properties of Hard Magnetic Alloys 30Kh21K3M and 30Kh20K2M2V

    NASA Astrophysics Data System (ADS)

    Stel'mashok, S. I.; Milyaev, I. M.; Yusupov, V. S.; Milyaev, A. I.

    2017-01-01

    The magnetic and mechanical properties of two hard magnetic alloys (30Kh21K3M and 30Kh20K2M2V) of the Fe - Cr - Co system in anisotropic and isotropic conditions produced by traditional induction melting and by the method of powder metallurgy with subsequent pressure treatment of the metal are studied. The obtained regression equations for B r , H cB and ( BH )max describe the quantities adequately in the used range of variation of factors. The response surfaces and their sections in the phase space of the heat treatment factors are plotted. The results of the analysis of the proportion of residual induction in anisotropic and isotropic states are used to infer that the model of the mechanism of magnetization reversal of hard magnetic alloys of the class considered needs amending.

  2. Is an arsenic-antisite-defect a constituent of hydrogen-related metastable defects (M3/M4) in GaAs?

    SciTech Connect

    Okumura, T.; Shinagawa, T.

    1998-12-31

    The hydrogen-related metastable defects (M3/M4) in n-GaAs, first found by Buchwald et al., were introduced only in the crystals containing the EL2 center. Off-center oxygen (=EL3), could not be responsible for their formation. A quantitative analysis with the samples exposed to atomic hydrogen showed that the M4 defect consisted of two different configurations. One of them did couple with M3, but is latent in the as-exposed state. It was formed after bias annealing at higher temperatures, such as 420 K. The other part of the M4 defect (M4{sup *}) existed at room temperature and after annealing at 513K, but disappeared and reappeared upon forward- and reverse-bias annealings, respectively.

  3. Ab-Initio Study on Plutonium Compounds Pu3M (M=Al, Ga, In), PuNp and Elemental Neptunium

    SciTech Connect

    Kutepov, A L

    2005-09-07

    Using spin-polarized relativistic density functional theory the electronic and magnetic structures for the plutonium compounds Pu{sub 3}M(M = Al; Ga; In) and PuNp have been investigated. For the first group of compounds the enhanced hybridization between Pu 5f and p-states of alloying element, as it has been found in spin-polarized calculations, is believed to be the main reason for the higher formation energies obtained in such kind of studies in comparison with the non-spin-polarized case. Also, comparative analysis of the actinides U, Np, Pu, Am, and Cm has been performed based on their electronic and magnetic structure. Some noticeable difference in the calculated magnetic structure was discovered between the actinide with local magnetic moments (Cm) and the actinides (Pu, Am) in which magnetic moments were found only in the calculations.

  4. Tudor-SN, a component of stress granules, regulates growth under salt stress by modulating GA20ox3 mRNA levels in Arabidopsis.

    PubMed

    Yan, Chunxia; Yan, Zongyun; Wang, Yizheng; Yan, Xiaoyuan; Han, Yuzhen

    2014-11-01

    The Tudor-SN protein (TSN) is universally expressed and highly conserved in eukaryotes. In Arabidopsis, TSN is reportedly involved in stress adaptation, but the mechanism involved in this adaptation is not understood. Here, we provide evidence that TSN regulates the mRNA levels of GA20ox3, a key enzyme for gibberellin (GA) biosynthesis. The levels of GA20ox3 transcripts decreased in TSN1/TSN2 RNA interference (RNAi) transgenic lines and increased in TSN1 over-expression (OE) transgenic lines. The TSN1 OE lines displayed phenotypes that may be attributed to the overproduction of GA. No obvious defects were observed in the RNAi transgenic lines under normal conditions, but under salt stress conditions these lines displayed slower growth than wild-type (WT) plants. Two mutants of GA20ox3, ga20ox3-1 and -2, also showed slower growth under stress than WT plants. Moreover, a higher accumulation of GA20ox3 transcripts was observed under salt stress. The results of a western blot analysis indicated that higher levels of TSN1 accumulated after salt treatment than under normal conditions. Subcellular localization studies showed that TSN1 was uniformly distributed in the cytoplasm under normal conditions but accumulated in small granules and co-localized with RBP47, a marker protein for stress granules (SGs), in response to salt stress. The results of RNA immunoprecipitation experiments indicated that TSN1 bound GA20ox3 mRNA in vivo. On the basis of these findings, we conclude that TSN is a novel component of plant SGs that regulates growth under salt stress by modulating levels of GA20ox3 mRNA.

  5. The Association between Splenocyte Apoptosis and Alterations of Bax, Bcl-2 and Caspase-3 mRNA Expression, and Oxidative Stress Induced by Dietary Nickel Chloride in Broilers

    PubMed Central

    Huang, Jianying; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Wu, Bangyuan

    2013-01-01

    Two hundred and forty avian broilers were equally divided into four groups, and raised with a corn-soybean basal diet or the same diet supplemented with 300, 600, 900 mg/kg NiCl2 for 42 days. Numbers or percentages of apoptotic splenocytes by flow cytometry (FCM) and TUNEL were higher (p < 0.05 or p < 0.01) in the 300, 600 and 900 mg/kg groups than those in the control group. Results measured by qRT-PCR and ELISA showed that mRNA expression and contents were significantly higher (p < 0.05 or p < 0.01) in Bax and Caspase-3, and were significantly lower (p < 0.05 or p < 0.01) in Bcl-2 of the 300, 600 and 900 mg/kg groups. Also, the SOD, CAT and GSH-Px activities, and the ability to inhibit hydroxyl radical, and GSH contents were significantly decreased (p < 0.05 or p < 0.01), and MDA contents were increased (p < 0.05 or p < 0.01) in all groups. In conclusion, dietary NiCl2 in excess of 300 mg/kg caused apoptosis, altered Bax, Bcl-2 and Caspase-3 mRNA expression levels and contents, and induced oxidative stress in the spleen. Also, splenocyte apoptosis was closely related to the alternations of Bax, Bcl-2 and Caspase-3 mRNA expression, and oxidative damage. The splenic immunity and blood filtration functions were impaired in broilers. PMID:24351749

  6. SF3M software: 3-D photo-reconstruction for non-expert users and its application to a gully network

    NASA Astrophysics Data System (ADS)

    Castillo, C.; James, M. R.; Redel-Macías, M. D.; Pérez, R.; Gómez, J. A.

    2015-08-01

    Three-dimensional photo-reconstruction (PR) techniques have been successfully used to produce high-resolution surface models for different applications and over different spatial scales. However, innovative approaches are required to overcome some limitations that this technique may present for field image acquisition in challenging scene geometries. Here, we evaluate SF3M, a new graphical user interface for implementing a complete PR workflow based on freely available software (including external calls to VisualSFM and CloudCompare), in combination with a low-cost survey design for the reconstruction of a several-hundred-metres-long gully network. SF3M provided a semi-automated workflow for 3-D reconstruction requiring ~ 49 h (of which only 17 % required operator assistance) for obtaining a final gully network model of > 17 million points over a gully plan area of 4230 m2. We show that a walking itinerary along the gully perimeter using two lightweight automatic cameras (1 s time-lapse mode) and a 6 m long pole is an efficient method for 3-D monitoring of gullies, at a low cost (~ EUR 1000 budget for the field equipment) and the time requirements (~ 90 min for image collection). A mean error of 6.9 cm at the ground control points was found, mainly due to model deformations derived from the linear geometry of the gully and residual errors in camera calibration. The straightforward image collection and processing approach can be of great benefit for non-expert users working on gully erosion assessment.

  7. Equatorial electrojet 3-M irregularity dynamics during magnetic disturbances over Brazil: results from the new VHF radar at Sa~o Luís

    NASA Astrophysics Data System (ADS)

    Abdu, M. A.; Dinardini, C. M.; Sobral, J. H. A.; Batista, I. S.; Muralikrishna, P.; Iyer, K. N.; Veliz, O.; de Paula, E. R.

    2003-09-01

    Data collected during the first two observational campaigns, conducted in August 1998 and December 1999, using the new 50MHz coherent back-scatter radar, developed at INPE, that became operational at the magnetic equatorial site at Sa~o Luís, (2.33°S,44.2°W), Brazil, are analyzed in this paper. The spatial and temporal distribution of 3-m irregularity power in the form of range-time-intensity maps and spectral distribution in the form of spectrograms are analyzed for `quiet' conditions and during geomagnetic storm disturbances. The analysis has brought out some new findings, besides confirming some of the already known storm response features of the EEJ and its plasma instabilities. Among the highlights of the results are: the electrical coupling between the equatorial and auroral electrojets is important even on a `quiet' day, and gets very strong during magnetic storm disturbances; disturbance prompt penetration electric field, and the delayed electric field from disturbance dynamo, control the 3-m plasma wave development and inhibition in different degrees during the storm main phase and recovery phase; the amplitudes of the disturbance are larger during the morning hours than in the afternoon, in agreement with theoretical models; the height dependence of the relative dominance of the type-1 and type-2 waves generated by disturbance electric field is different from that of quiet conditions, the relative power of the type-2 getting enhanced at higher levels in the former case. A few other results are also discussed in this paper.

  8. Carbon-Carbon Piston Architectures

    NASA Technical Reports Server (NTRS)

    Rivers, H. Kevin (Inventor); Ransone, Philip O. (Inventor); Northam, G. Burton (Inventor); Schwind, Francis A. (Inventor)

    2000-01-01

    An improved structure for carbon-carbon composite piston architectures is disclosed. The improvement consists of replacing the knitted fiber, three-dimensional piston preform architecture described in U.S. Pat.No. 4,909,133 (Taylor et al.) with a two-dimensional lay-up or molding of carbon fiber fabric or tape. Initially, the carbon fabric of tape layers are prepregged with carbonaceous organic resins and/or pitches and are laid up or molded about a mandrel, to form a carbon-fiber reinforced organic-matrix composite part shaped like a "U" channel, a "T"-bar, or a combination of the two. The molded carbon-fiber reinforced organic-matrix composite part is then pyrolized in an inert atmosphere, to convert the organic matrix materials to carbon. At this point, cylindrical piston blanks are cored from the "U"-channel, "T"-bar, or combination part. These blanks are then densified by reimpregnation with resins or pitches which are subsequently carbonized. Densification is also accomplished by direct infiltration with carbon by vapor deposition processes. Once the desired density has been achieved, the piston billets are machined to final piston dimensions; coated with oxidation sealants; and/or coated with a catalyst. When compared to conventional steel or aluminum alloy pistons, the use of carbon-carbon composite pistons reduces the overall weight of the engine; allows for operation at higher temperatures without a loss of strength; allows for quieter operation; reduces the heat loss; and reduces the level of hydrocarbon emissions.

  9. Oxalate-based soluble 2D magnets: the series [K(18-crown-6)]3[M(II)3(H2O)4{M(III)(ox)3}3] (M(III) = Cr, Fe; M(II) = Mn, Fe, Ni, Co, Cu; ox = C2O4(2-); 18-crown-6 = C12H24O6).

    PubMed

    Coronado, Eugenio; Galán-Mascarós, José R; Martí-Gastaldo, Carlos; Waerenborgh, João C; Gaczyński, Piotr

    2008-08-04

    The synthesis and magnetic properties of the oxalate-based molecular soluble magnets with general formula [K(18-crown-6)] 3[M (II) 3(H 2O) 4{M (III)(ox) 3} 3] (M (III) = Cr, Fe; M (II) = Mn, Fe, Ni, Co, Cu; ox = C 2O 4 (2-)) are here described. All the reported compounds are isostructural and built up by 2D bimetallic networks formed by alternating M (III) and M (II) ions connected through oxalate anions. Whereas the Cr (III)M (II) derivatives behave as ferromagnets with critical temperatures up to 8 K, the Fe (III)M (II) present ferri- or weak ferromagnetic ordering up to 26 K.

  10. Temperature sensitivity (Q10), and dynamics of soil organic matter (SOM) decomposition in permafrost soils with different carbon quality and under experimental warming. R. Bracho1, E.A.G Schuur1, E. Pegoraro1, K.G. Crummer1, S. Natali2, J. Zhou, Y Luo3, J. L. Wu3, M. Tiedje4, K. Konstantinidis5 1Department of Biology, University of Florida, Gainesville, FL. 2Woods Hole Research Center, Falmouth, MA. 3Institute for Environmental Genomics and Department of Botany and Microbiology, University of Oklahoma, Norman, OK, 4Center for Microbial Ecology, Michigan State University, East Lansing, MI; 5Center for Bioinformatics and Computational Genomics and School of Biology, Georgia Institute of Technology, Atlanta, GA

    NASA Astrophysics Data System (ADS)

    Bracho, R. G.; Schuur, E. A.; Pegoraro, E.; Crummer, K. G.; Natali, S.; Zhou, J.; Wu, L.; Luo, Y.; Tiedje, J. M.; Konstantinidis, K.

    2013-12-01

    Permafrost soils contain approximately1700 Pg of carbon (C), twice the amount of C in the atmosphere. Temperatures in higher latitudes are increasing, inducing permafrost thaw and subsequent microbial decomposition of previously frozen C. This process is one of the most likely positive feedbacks to climate change. Understanding the temperature sensitivity (Q10) and dynamics of SOM decomposition under warming is essential to predict the future state of the earth - climate system. Alaskan tundra soils were exposed to two winter warming (WW) seasons in the field, which warmed the soils by 4°C to 40 cm depth. Soils were obtained from three depths (0 - 15, 15 - 25 and 45 - 55 cm) and differed in initial amounts of labile and recalcitrant C. Soils were incubated in the lab under aerobic conditions, at 15 and 25°C over 365 days. Q10 was estimated at 14, 100 & 280 days of incubation (DOI); C fluxes were measured periodically and dynamics of SOM decomposition (C pool sizes and decay rates) were estimated by fitting a two pool C model to cumulative respired C (Ccum, mgC/ginitialC). After two WW seasons, initial C content tended to decrease through the soil profile and C:N ratio was significantly decreased in the top 15 cm. After one year of incubation, Ccum was twice as high at 25°C as at 15°C and significantly decreased with depth. No significant WW field treatment was detected, although Ccum tended to be lower in warmed soils. Labile C accounted for up to 5% of initial soil C content in the top 15 cm and decreased with depth. Soils exposed to WW had smaller labile C pools, and higher labile C decay rates in the top 25 cm. Q10 significantly decreased with time and depth as labile pool decreased, especially for WW. This decrease with time indicates a lower temperature sensitivity of the most recalcitrant C pool. The deepest WW soil layer, where warming was more pronounced, had significantly lower Q10 compared to control soils at the same depth. After two seasons, the

  11. Developments in carbon materials

    NASA Technical Reports Server (NTRS)

    Burchell, Timothy D.

    1994-01-01

    The following carbon-based materials are reviewed and their applications discussed: fullerenes; graphite (synthetic and manufactured); activated carbon fibers; and carbon-carbon composites. Carbon R&D activities at ORNL are emphasized.

  12. pH-controlled coordination mode rearrangements of "clickable" Huisgen-based multidentate ligands with [M(I)(CO)3]+ (M = Re, (99m)Tc).

    PubMed

    Bottorff, Shalina C; Moore, Adam L; Wemple, Ariana R; Bučar, Dejan-Krešimir; MacGillivray, Leonard R; Benny, Paul D

    2013-03-18

    The viability of the Huisgen cycloaddition reaction for clickable radiopharmaceutical probes was explored with an alkyne-functionalized 2-[(pyridin-2-ylmethyl)amino]acetic acid (PMAA) ligand system, 3, and fac-[M(I)(OH2)3(CO)3](+) (M = Re, (99m)Tc). Two synthetic strategies, (1) click, then chelate and (2) chelate, then click, were investigated to determine the impact of assembly order on the reactivity of the system. In the click, then chelate approach, fac-[M(I)(OH2)3(CO)3](+) was reacted with the PMAA ligand "clicked" to the benzyl azide, 5, to yield two unique coordination species, fac-[M(I)(CO)3(O,N(amine),N(py)-5)], M = Re (8), (99m)Tc (8A), and fac-[M(I)(CO)3(N(tri),N(amine),N(py)-5)], M = Re (9), (99m)Tc (9A), where coordination is through the triazole (N(tri)), central amine (N(amine)), pyridine (N(py)), or carboxylate (O). Depending on the reaction pH, different ratios of complexes 8(A) and 9(A) were observed, but single species were obtained of (O,N(amine),N(py)) coordination, 8(A), in basic pHs (>9) and (N(tri),N(amine),N(py)) coordination, 9(A), in slightly acidic pHs (<4). In the chelate, then click approach, the (O,N(amine),N(py)) coordination of [M(I)(CO)3](+) was preorganized in the alkyne-functionalized fac-[M(I)(CO)3(O,N(amine),N(py)-3)], M = Re (6), (99m)Tc (6A), followed by standard Cu(I)-catalyzed Huisgen "click" conditions at pH ≈ 7.4, where the (O,N(amine),N(py)) coordination mode remained unchanged upon formation of the triazole product in the clicked molecule. Despite the slow substitution kinetics of the low-spin d(6) metal, the coordination modes (O,N(amine),N(py)) and (N(tri),N(amine),N(py)) were found to reversibly intraconvert between 8(A) and 9(A) based upon changes in pH that mirrored the (O,N(amine),N(py)) coordination in basic pHs and (N(tri),N(amine),N(py)) coordination in acidic pHs. Comparison of the Re and (99m)Tc analogs also revealed faster intraconversion between the coordination modes for (99m)Tc.

  13. Calcium Carbonate.

    PubMed

    Al Omari, M M H; Rashid, I S; Qinna, N A; Jaber, A M; Badwan, A A

    2016-01-01

    Calcium carbonate is a chemical compound with the formula CaCO3 formed by three main elements: carbon, oxygen, and calcium. It is a common substance found in rocks in all parts of the world (most notably as limestone), and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. CaCO3 exists in different polymorphs, each with specific stability that depends on a diversity of variables.

  14. Infiltrated carbon foam composites

    NASA Technical Reports Server (NTRS)

    Lucas, Rick D. (Inventor); Danford, Harry E. (Inventor); Plucinski, Janusz W. (Inventor); Merriman, Douglas J. (Inventor); Blacker, Jesse M. (Inventor)

    2012-01-01

    An infiltrated carbon foam composite and method for making the composite is described. The infiltrated carbon foam composite may include a carbonized carbon aerogel in cells of a carbon foam body and a resin is infiltrated into the carbon foam body filling the cells of the carbon foam body and spaces around the carbonized carbon aerogel. The infiltrated carbon foam composites may be useful for mid-density ablative thermal protection systems.

  15. Carbon and Energy Sources for the Nitrifying Autotroph Nitrobacter

    PubMed Central

    Delwiche, C. C.; Finstein, M. S.

    1965-01-01

    Delwiche, C. C. (University of California, Davis), and M. S. Finstein. Carbon and energy sources for the nitrifying autotroph Nitrobacter. J. Bacteriol. 90:102–107. 1965.—The effect of various organic compounds on the growth and metabolism of the obligatively autotrophic nitrifying organism Nitrobacter was studied. A slight stimulation of both nitrification and growth was obtainable with a number of organic amendments, including yeast extract, Vitamin Free Casamino Acids, and some amino acids. Depending upon culture conditions, a strong stimulation of growth was obtained with acetate as an amendment to the culture solution. Several compounds, including valine, hydroxyproline, and threonine, were inhibitory at concentrations of 10−3m. The incorporation of carbon from isotopically labeled organic compounds was demonstrated. Acetate and glycine were particularly strong contributors to cell carbons. These could not substitute for carbon dioxide as a sole carbon source for growth, however, nor could any other of the carbon compounds that were tried. PMID:16562002

  16. Deep Soil Carbon: The Insight into Global Carbon Estimation and Deforestation Impacts

    NASA Astrophysics Data System (ADS)

    Sangmanee, Podjanee; Dell, Bernard; Harper, Richard; Henry, David

    2015-04-01

    World carbon stocks have been dramatically changed by deforestation. The current estimation of carbon loss is based on allometric techniques assisted with satellite imagery and the assumption that, 20% of the total biomass carbon stock is below ground. However, the monitoring of soil carbon is limited to 0.3 m despite many soils being much deeper than this. For example, direct measurement of soil carbon demonstrated the occurrence of two to five times more carbon stored in deep soils of south Western Australia (SWA) compared to what would normally be reported, although the land had been deforested for 80 years. This raises important questions about the dynamics of this deeper carbon and whether it will contribute to global climate change. This paper reports the form and variation of carbon in soil at three adjacent areas at three different depths (0-1, 11-12 and 18-19 m). Techniques were developed to quantitatively and qualitatively determine small concentrations of carbon in deep soils. There were marked differences in carbon compounds with depth. Near the surface these were macromolecular organic compounds derived from lignin, polysaccharides, proteins, terpenes, whereas at depth they were low molecular weight compounds, 13-docosenamide, 13-docosenoate, xanthone, benzophenone. The deeper compounds are likely derived from the roots of the previous forest whereas the surface soils are affected by current land use. The in situ decomposition of deep roots was revealed by the pyridine compound. The variation of compounds and location of carbon in clay could imply the state of decomposition. The result demonstrated that carbon is contained in deep soils and should be considered in global carbon accounting, particularly given ongoing deforestation on deep soils.

  17. Reduction properties of phases in the system La 0.5Sr 0.5MO 3 ( M=Fe, Co)

    NASA Astrophysics Data System (ADS)

    Berry, Frank J.; Marco, José F.; Ren, Xiaolin

    2005-04-01

    Phases formed by the reduction of compounds of the type La 0.5Sr 0.5MO 3 ( M=Fe, Co) have been characterized by means of temperature programmed reduction, X-ray powder diffraction, 57Fe Mössbauer spectroscopy and Fe K-, Co K-, Sr K-, and La L III-edge X-ray absorption spectroscopy. The results show that treatment of the material of composition La 0.5Sr 0.5FeO 3 (which contains 50% Fe 4+ and 50% Fe 3+) at 650 °C in a flowing 90% hydrogen/10% nitrogen atmosphere results in the formation of an oxygen-deficient perovskite-related phase containing only trivalent iron. Further heating in the gaseous reducing environment at 1150 °C results in the formation of the Fe 3+-containing phase SrLaFeO 4, which has a K 2NiF 4-type structure, and metallic iron. The material of composition La 0.5Sr 0.5CoO 3 is more susceptible to reduction than the compound La 0.5Sr 0.5FeO 3 since, after heating at 520 °C in the hydrogen/nitrogen mixture, all the Co 4+ and Co 3+ are reduced to metallic cobalt with the concomitant formation of strontium- and lanthanum-oxides.

  18. Single layer of MX3(M = Ti, Zr; X = S, Se, Te): a new platform for nano-electronics and optics

    NASA Astrophysics Data System (ADS)

    Jin, Yingdi; Li, Xingxing; Yang, Jinlong

    A serial of two dimensional titanium and zirconium trichalcogenides nanosheets MX3 (M=Ti, Zr; X=S, Se, Te) are investigated based on first-principles calculations. The evaluated low cleavage energy indicates that stable two dimensional monolayers can be exfoliated from their bulk crystals in experiment. Electronic studies reveal very rich electronic properties in these monolayers, including metallic TiTe3 and ZrTe3, direct band gap semiconductor TiS3 and indirect band gap semiconductors TiSe3, ZrS3 and ZrSe3. The band gaps of all the semiconductors are between 0.57~1.90 eV, which implies their potential applications in nano-electronics. And the calculated effective masses demonstrate highly anisotropic conduction properties for all the semiconductors. Optically, TiS3 and TiSe3 monolayers exhibit good light absorption in the visible and near-infrared region respectively, indicating their potential applications in optical devices. In particular, the highly anisotropic optical absorption of TiS3 monolayer suggests it could be used in designing nano optical waveguide polarizers.

  19. The Structure of the yFACT Pob3-M Domain, Its Interaction with the DNA Replication Factor RPA, and a Potential Role in Nucleosome Deposition

    SciTech Connect

    VanDemark,A.; Blanksma, M.; Ferris, E.; Heroux, A.; Hill, C.; Formosa, T.

    2006-01-01

    We report the crystal structure of the middle domain of the Pob3 subunit (Pob3-M) of S. cerevisiae FACT (yFACT, facilitates chromatin transcription), which unexpectedly adopts an unusual double pleckstrin homology (PH) architecture. A mutation within a conserved surface cluster in this domain causes a defect in DNA replication that is suppressed by mutation of replication protein A (RPA). The nucleosome reorganizer yFACT therefore interacts in a physiologically important way with the central single-strand DNA (ssDNA) binding factor RPA to promote a step in DNA replication. Purified yFACT and RPA display a weak direct physical interaction, although the genetic suppression is not explained by simple changes in affinity between the purified proteins. Further genetic analysis suggests that coordinated function by yFACT and RPA is important during nucleosome deposition. These results support the model that the FACT family has an essential role in constructing nucleosomes during DNA replication, and suggest that RPA contributes to this process.

  20. Oxide composite prepared from intermetallic and amorphous Zr67Fe30M3- (M=Au, Pt) alloys and their catalytic activity for CO oxidation

    NASA Astrophysics Data System (ADS)

    Huang, Yung-Han; Wang, Sea-Fue; Kameoka, Satoshi; Miyamoto, Kanji; Tsai, An-Pang

    2017-01-01

    In this study, Zr67Fe30M3 (M=Au, Pt) intermetallic compounds and amorphous alloys were prepared and used as precursors for the synthesis of oxides. Oxidation treatment of the intermetallic compounds at 500 °C followed by X-ray diffraction (XRD) analysis indicated that zirconium and iron were oxidized to ZrO2 and Fe2O3, respectively. In the case of Zr67Fe30M3 amorphous alloys, cubic Zr6Fe3O was observed on the surface of the ribbons after heat treatment at 500 °C in vacuum. Addition of 3% of gold or platinum to the alloy resulted in an increase in the lattice constants of the Zr6Fe3O phase. Grounding the treated ribbons into powders followed by an oxidation treatment at 500 °C in air produced Fe2O3 and ZrO2 supports, where Au and Pt are dissolved in the oxides as confirmed by X-ray photoelectron spectroscopy (XPS). No matter precursors are intermetallics or amorphous phases, the resultant oxides are the same. Although Pt and Au dissolved in the oxides, catalytic activities for CO oxidation were significant improved.

  1. Design of a 1.12 Gb/s 11.3 mW low-voltage differential signaling transmitter

    NASA Astrophysics Data System (ADS)

    Yuan, Su; Jixuan, Xiang; Xiaoying, Shen; Fan, Ye; Junyan, Ren

    2015-04-01

    This paper presents a 1.12 Gb/s 11.3 mW transmitter using 0.18 μm mixed signal complementary metal-oxide semiconductor technology with a 1.8 V supply voltage. This transmitter implements a high-speed transmission with 1.2 V common-mode output voltage, adopting a low-voltage differential signaling (LVDS) technique. A multiplexer (MUX) and an LVDS driver are critical for a transmitter to complete a high-speed data transmission. This paper proposes a high power-efficiency single-stage 14 : 1 MUX and an adjustable LVDS driver circuit, capable of driving different loads with a slight increase in power consumption. The prototype chip implements a transmitter with a core area of 970 × 560 μm2, demonstrating low power consumption and adjustable driving capability. Project supported by the National Science and Technology Support Program of China (No. 2012BAI13B07) and the National High-Tech Research and Development Program of China (No. 2013AA014101).

  2. Changes in T cell subsets identify responders to FcR non-binding anti-CD3 mAb (teplizumab) in patients with Type 1 diabetes

    PubMed Central

    Tooley, James E; Vudattu, Nalini; Choi, Jinmyung; Cotsapas, Chris; Devine, Lesley; Raddassi, Khadir; Ehlers, Mario R; McNamara, James G; Harris, Kristina M; Kanaparthi, Sai; Phippard, Deborah; Herold, Kevan C

    2016-01-01

    The mechanisms whereby immune therapies affect progression of Type 1 diabetes (T1D) are not well understood. Teplizumab, an FcR non-binding anti-CD3 mAb, has shown efficacy in multiple randomized clinical trials. We previously reported an increase in the frequency of circulating CD8+ central memory (CD8CM) T cells in clinical responders, but the generalizability of this finding and the molecular effects of teplizumab on these T cells have not been evaluated. We analyzed data from 2 randomized clinical studies of teplizumab in patients with new and recent onset T1D. At the conclusion of therapy clinical responders showed a significant reduction in circulating CD4+ effector memory (CD4EM) T cells. Afterwards, there was an increase in the frequency and absolute number of CD8CM T cells. In vitro, teplizumab expanded CD8CM T cells by proliferation and conversion of non-CM T cells. Nanostring analysis of gene expression of CD8CM T cells from responders and non-responders vs placebo-treated control subjects identified decreases in expression of genes associated with immune activation and increases in expression of genes associated with T cell differentiation and regulation. We conclude that CD8CM T cells with decreased activation and regulatory gene expression are associated with clinical responses to teplizumab in patients with T1D. PMID:26518356

  3. Changes in T-cell subsets identify responders to FcR-nonbinding anti-CD3 mAb (teplizumab) in patients with type 1 diabetes.

    PubMed

    Tooley, James E; Vudattu, Nalini; Choi, Jinmyung; Cotsapas, Chris; Devine, Lesley; Raddassi, Khadir; Ehlers, Mario R; McNamara, James G; Harris, Kristina M; Kanaparthi, Sai; Phippard, Deborah; Herold, Kevan C

    2016-01-01

    The mechanisms whereby immune therapies affect progression of type 1 diabetes (T1D) are not well understood. Teplizumab, an FcR nonbinding anti-CD3 mAb, has shown efficacy in multiple randomized clinical trials. We previously reported an increase in the frequency of circulating CD8(+) central memory (CD8CM) T cells in clinical responders, but the generalizability of this finding and the molecular effects of teplizumab on these T cells have not been evaluated. We analyzed data from two randomized clinical studies of teplizumab in patients with new- and recent-onset T1D. At the conclusion of therapy, clinical responders showed a significant reduction in circulating CD4(+) effector memory T cells. Afterward, there was an increase in the frequency and absolute number of CD8CM T cells. In vitro, teplizumab expanded CD8CM T cells by proliferation and conversion of non-CM T cells. Nanostring analysis of gene expression of CD8CM T cells from responders and nonresponders versus placebo-treated control subjects identified decreases in expression of genes associated with immune activation and increases in expression of genes associated with T-cell differentiation and regulation. We conclude that CD8CM T cells with decreased activation and regulatory gene expression are associated with clinical responses to teplizumab in patients with T1D.

  4. Measurements in the flow field of a cylinder with a laser transit anemometer and a drag rake in the Langley 0.3 m transonic cryogenic tunnel

    NASA Technical Reports Server (NTRS)

    Honaker, W. C.; Lawing, P. L.

    1985-01-01

    An experiment was conducted at the 0.3 m Transonic Cryogenic Tunnel using a Laser Transit Anemometer (LTA) to probe the flow field around a 3.05 centimeter-diameter circular cylinder. Measurements were made along the stagnation line and determination of particle size was evaluated by their ability to follow the flow field. The LTA system was also used to scan into the boundary layer near the 45 degree point on the model. Results of these scans are presented in graphic and tabular form. Flow field particle seeding was accomplished by inbleeding dry service air. The residual moisture (5-10 ppm) condensed and formed ice particles which served as Mie scattering centers for the LTA detection system. Comparison of data taken along the stagnation streamline with theory indicated that these particles tracked the velocity gradient of the flow. Tunnel operating conditions for the tests were a Mach number of 0.3, a pressure of 1.93 x 100000 n/m squared, and a temperature of 225 degrees K. Free stream Mach number and pressure were varied for the particle size determination.

  5. Microwave-assisted synthesis: A fast and efficient route to produce LaMO{sub 3} (M = Al, Cr, Mn, Fe, Co) perovskite materials

    SciTech Connect

    Prado-Gonjal, J.; Arevalo-Lopez, A.M.; Moran, E.

    2011-02-15

    Research highlights: {yields} Lanthanum perovskites can be prepared by microwave irradiation in a domestic set-up. {yields} Microwave-assisted synthesis yields well crystallized and pure materials, sometimes nanosized. {yields} Rietveld analysis has been performed to refine the structures. {yields} Magnetic and electric measurements are similar to those previously reported. {yields} Microwave-assisted synthesis is a fast and efficient method for the synthesis of lanthanum perovskites. -- Abstract: A series of lanthanum perovskites, LaMO{sub 3} (M = Al, Cr, Mn, Fe, Co), having important technological applications, have been successfully prepared by a very fast, inexpensive, reproducible, environment-friendly method: the microwave irradiation of the corresponding mixtures of nitrates. Worth to note, the microwave source is a domestic microwave oven. In some cases the reaction takes place in a single step, while sometimes further annealings are necessary. For doped materials the method has to be combined with others such as sol-gel. Usually, nanopowders are produced which yield high density pellets after sintering. Rietveld analysis, oxygen stoichiometry, microstructure and magnetic measurements are presented.

  6. Blazar variability studies with the 1.3m Robotically Controlled Telescope and the automated 0.6m Bell Observatory telescope

    NASA Astrophysics Data System (ADS)

    Carini, M. T.; Barnaby, D.; Mattox, J. R.; Walters, R.; Poteet, C.; Wills, W.; Gelderman, R.; Davis, D.; Everett, M.; Guinan, E.; Howell, S.; McGruder, C. H., III

    2004-10-01

    One of the key programs on the 1.3m Robotically Controlled Telescope (RCT) located at Kitt Peak National Observatory and the 0.6m telescope at the Bell Observatory operated by Western Kentucky University is a study of the variability of the class of Active Galactic Nuclei (AGN) known as Blazars. Blazars are highly variable on timescales of minutes to decades and this variability is seen across the electromagnetic spectrum. In addition, they display a featureless spectrum, thus continuum variability provides the only diagnostic of these objects. Variability provides information on the size of the emission region responsible for the observed variations and when observations are obtained at multiple wavelengths, it can be used to discriminate between emission models. However, traditional ground based observations are limited in a variety of ways. We will discuss how an automated facility, with time dedicated to this astrophysically interesting problem, can overcome many of these limitations, and we show results from the Bell Observatory as well as some of the first results of Blazar observations from the RCT.

  7. IFNL3 mRNA structure is remodeled by a functional non-coding polymorphism associated with hepatitis C virus clearance.

    PubMed

    Lu, Yi-Fan; Mauger, David M; Goldstein, David B; Urban, Thomas J; Weeks, Kevin M; Bradrick, Shelton S

    2015-11-04

    Polymorphisms near the interferon lambda 3 (IFNL3) gene strongly predict clearance of hepatitis C virus (HCV) infection. We analyzed a variant (rs4803217 G/T) located within the IFNL3 mRNA 3' untranslated region (UTR); the G allele (protective allele) is associated with elevated therapeutic HCV clearance. We show that the IFNL3 3' UTR represses mRNA translation and the rs4803217 allele modulates the extent of translational regulation. We analyzed the structures of IFNL3 variant mRNAs at nucleotide resolution by SHAPE-MaP. The rs4803217 G allele mRNA forms well-defined 3' UTR structure while the T allele mRNA is more dynamic. The observed differences between alleles are among the largest possible RNA structural alterations that can be induced by a single nucleotide change and transform the UTR from a single well-defined conformation to one with multiple dynamic interconverting structures. These data illustrate that non-coding genetic variants can have significant functional effects by impacting RNA structure.

  8. Structure determination and relative properties of novel cubic borates MM'4(BO3)3 (M = Li, M' = Sr; M = Na, M' = Sr, Ba).

    PubMed

    Wu, L; Chen, X L; Li, H; He, M; Xu, Y P; Li, X Z

    2005-09-05

    A series of novel borates, MM'4(BO3)3 (M = Li, M' = Sr; M = Na, M' = Sr, Ba), have been successfully synthesized by standard solid-state reaction. The crystal structures have been determined from powder X-ray diffraction data. They crystallize in the cubic space group Iad with large lattice parameters: a = 14.95066(5) A for LiSr4(BO3)3, a = 15.14629(6) A for NaSr4(BO3)3, and a = 15.80719(8) A for NaBa4(BO3)3. The structure was built up from 64 small cubic grids, in which the M' atoms took up the corner angle and the BO3 triangles or MO6 cubic octahedra filled in the interspaces. The isolated [BO3]3- anionic groups are perpendicular to each other, distributed along three 100 directions. The anisotropic polarizations were counteracting, forming an isotropic crystal. Sr and Ba atoms were found to be completely soluble in the solid solution NaSr(4-)xBax(BO3)3 (0 < or = x < or = 4). The photoluminescence of samples doped with the ions Eu2+ and Eu3+ was studied, and effective yellow and red emission was detected, respectively. The results are consistent with the crystallographic study. The DTA and TGA curves of them show that they are chemically stable and congruent melting compounds.

  9. Curcumin as the OO bidentate ligand in "2 + 1" complexes with the [M(CO)3]+ (M = Re, 99mTc) tricarbonyl core for radiodiagnostic applications.

    PubMed

    Sagnou, Marina; Benaki, Dimitra; Triantis, Charalampos; Tsotakos, Theodoros; Psycharis, Vassilis; Raptopoulou, Catherine P; Pirmettis, Ioannis; Papadopoulos, Minas; Pelecanou, Maria

    2011-02-21

    The synthesis and characterization of "2 + 1" complexes of the [M(CO)(3)](+) (M = Re, (99m)Tc) core with the β-diketones acetylacetone (complexes 2, 8) and curcumin (complexes 5, 10 and 6, 11) as bidentate OO ligands, and imidazole or isocyanocyclohexane as monodentate ligands is reported. The complexes were synthesized by reacting the [NEt(4)](2)[Re(CO)(3)Br(3)] precursor with the β-diketone to generate the intermediate aqua complex fac-Re(CO)(3)(OO)(H(2)O) that was isolated and characterized, followed by replacement of the labile water by the monodentate ligand. All complexes were characterized by mass spectrometry, NMR and IR spectroscopies, and elemental analysis. In the case of complex 2, bearing imidazole as the monodentate ligand, X-ray analysis was possible. The chemistry was successfully transferred at (99m)Tc tracer level. The curcumin complexes 5 and 6, as well as their intermediate aqua complex 4, that bear potential for radiopharmaceutical applications due to the wide spectrum of pharmacological activity of curcumin, were successfully tested for selective staining of β-amyloid plaques of Alzheimer's disease. The fact that the complexes maintain the affinity of the mother compound curcumin for β-amyloid plaques prompts for further exploration of their chemistry and biological properties as radioimaging probes.

  10. Etomoxir, sodium 2-[6-(4-chlorophenoxy)hexyl]oxirane-2-carboxylate, up-regulates uncoupling protein-3 mRNA levels in primary culture of rat preadipocytes.

    PubMed

    Cabrero, A; Alegret, M; Sánchez, R; Adzet, T; Laguna, J C; Vázquez, M

    1999-09-16

    Uncoupling proteins (UCPs) are mitochondrial membrane proton transporters that uncouple respiration from oxidative phosphorylation by dissipating the proton gradient across the membrane. Treatment of primary culture of rat preadipocytes for 24 h with 40 microM etomoxir, an irreversible inhibitor of carnitine palmitoyltransferase I (CPT-I), up-regulated UCP-3 mRNA levels (3. 6-fold induction), whereas changes in UCP-2 mRNA levels were not significant. As a consequence of increased UCP-3 expression, a fall in the mitochondrial membrane potential was detected by flow cytometry. Etomoxir treatment modified neither L-CPT-I (liver-type) nor PPARalpha mRNA levels in preadipocytes. In contrast, mRNA expression of acyl-CoA oxidase (ACO), the rate-limiting enzyme of peroxisomal fatty acid beta-oxidation, whose transcription is controlled by PPARalpha, was significantly induced (1.3-fold induction, P = 0.015). These findings suggest that the effects of etomoxir were mediated by PPARalpha. Since it has been reported that the intracellular accumulation of lipids following the inhibition of CPT-I by etomoxir leads to a PPARalpha-mediated metabolic response that increases the expression of genes involved in alternate fatty acid oxidation pathways, these results seem to implicate UCP-3 in this protective metabolic response. It remains to be studied whether reductions in the expression of UCP-3 could compromise this response, giving rise to lipotoxic effects on cells.

  11. Theoretical and experimental studies of formation and migration of oxygen vacancies in BaM x Ti1- x O3 (M = Zr, Ge)

    NASA Astrophysics Data System (ADS)

    Umeda, Yuji; Aman, Sanshiro; Kuwabara, Akihide; Moriwake, Hiroki

    2016-10-01

    The formation and migration energies of oxygen vacancies in pure BaTiO3, and BaM x Ti1- x O3 (M = Zr, Ge) are calculated by first-principles calculations to understand the effect of doping on the reliability of multilayer ceramic capacitors (MLCCs). The formation and migration energies of oxygen vacancies are found to be larger in BaZr x Ti1- x O3 than in BaTiO3. This finding could be one of the possible reasons behind the improved reliability of Zr-doped MLCCs materials. On the other hand, by substituting Ge, the migration energy of BaGe x Ti1- x O3 becomes larger than that of BaTiO3. This is despite the smaller oxygen vacancy formation energy in BaGe x Ti1- x O3 than in BaTiO3. Even though Zr and Ge are tetravalent in BaM x Ti1- x O3, their valence states are different after the formation of oxygen vacancies, providing an explanation for the differences in vacancy formation and migration energies between BaZr x Ti1- x O3 and BaGe x Ti1- x O3. Our theoretical results are further confirmed by experiments on these model systems.

  12. Influence of functionalized pyridine ligands on the radio/chemical behavior of [M(I)(CO)3](+) (M = Re and (99m)Tc) 2 + 1 complexes.

    PubMed

    Hayes, Thomas R; Lyon, Patrice A; Barnes, Charles L; Trabue, Steven; Benny, Paul D

    2015-02-16

    While a number of chelate strategies have been developed for the organometallic precursor fac-[M(I)(OH2)3(CO)3](+) (M = Re, (99m)Tc), a unique challenge has been to improve the overall function and performance of these complexes for in vivo and in vitro applications. Since its discovery, fac-[M(I)(OH2)3(CO)3](+) has served as an essential scaffold for the development of new targeted (99m)Tc based radiopharmaceuticals due to its labile aquo ligands. However, the lipophilic nature of the fac-[M(I)(CO)3](+) core can influence the in vivo pharmacokinetics and biodistribution of the complexes. In an effort to understand and improve this behavior, monosubstituted pyridine ligands were used to assess the impact of donor nitrogen basicity on binding strength and stability of fac-[M(I)(CO)3](+) in a 2 + 1 labeling strategy. A series of Re and (99m)Tc complexes were synthesized with picolinic acid as a bidentate ligand and 4-substituted pyridine ligands. These complexes were designed to probe the effect of pKa from the monodentate pyridine ligand both at the macro scale and radiochemical concentrations. Comparison of X-ray structural data and radiochemical solution experiments clearly indicate an increase in overall yield and stability as pyridine basicity increased.

  13. Dependence of electrical transport properties of CaO(CaMnO3)m (m = 1, 2, 3, ∞) thermoelectric oxides on lattice periodicity

    NASA Astrophysics Data System (ADS)

    Baranovskiy, Andrei; Amouyal, Yaron

    2017-02-01

    The electrical transport properties of CaO(CaMnO3)m (m = 1, 2, 3, ∞) compounds are studied applying the density functional theory (DFT) in terms of band structure at the vicinity of the Fermi level (EF). It is shown that the total density of states (DOS) values at EF increase with increase in the m-values, which implies an increase in the electrical conductivity, σ, with increasing m-values, in full accordance with experimental results. Additionally, the calculated values of the relative slopes of the DOS at EF correlate with the experimentally measured Seebeck coefficients. The electrical conductivity and Seebeck coefficients were calculated in the framework of the Boltzmann transport theory applying the constant relaxation time approximation. By the analysis of experimental and calculated σ(Τ) dependences, the electronic relaxation time and mean free path values were estimated. It is shown that the electrical transport is dominated by electron scattering on the boundaries between perovskite (CaMnO3) and Ca oxide (CaO) layers inside the crystal lattice.

  14. Structural and electronic properties of UnOm (n=1-3,m=1-3n) clusters: A theoretical study using screened hybrid density functional theory.

    PubMed

    Yang, Yu; Liu, Haitao; Zhang, Ping

    2016-05-14

    The structural and electronic properties of small uranium oxide clusters UnOm (n=1-3, m=1-3n) are systematically studied within the screened hybrid density functional theory. It is found that the formation of U-O-U bondings and isolated U-O bonds are energetically more stable than U-U bondings. As a result, no uranium cores are observed. Through fragmentation studies, we find that the UnOm clusters with the m/n ratio between 2 and 2.5 are very stable, hinting that UO2+x hyperoxides are energetically stable. Electronically, we find that the O-2p states always distribute in the deep energy range, and the U-5f states always distribute at the two sides of the Fermi level. The U-6d states mainly hybridize with the U-5f states in U-rich clusters, while hybridizing with O-2p states in O-rich clusters. Our work is the first one on the screened hybrid density functional theory level studying the atomic and electronic properties of the actinide oxide clusters.

  15. A feasibility study of using Langley 0.3-m transonic cryogenic tunnel sidewall boundary-layer removal system for heavy gas testing

    NASA Technical Reports Server (NTRS)

    Murthy, A. V.; Balakrishna, S.; Kilgore, W. Allen

    1993-01-01

    This report presents the results of a preliminary study for using the 0.3-m Transonic Cryogenic Tunnel sidewall boundary-layer removal system with heavy gas sulfur hexafluoride as the test medium. It is shown that the drive motor speed/power of the existing system and the additional heat load on the tunnel heat exchanger are the major problems limiting the boundary-layer removal system performance. Overcoming these problems can provide the capability to remove about 1.5 percent of the test section mass flow at Mach number M = 0.8 and about 5 percent at M = 0.25. Previous studies have shown that these boundary-layer mass flow removal rates can reduce the boundary-layer thickness by a factor of two at the model station. Also the effect of upstream boundary-layer removal on the airfoil test data is not likely to be significant under high lifting conditions. Near design conditions, corrections to the test Mach number may be necessary to account for sidewall boundary-layer effects.

  16. Control of orbital reconstruction in (LaAlO3)M/(SrTiO3)N(001) quantum wells by strain and confinement

    NASA Astrophysics Data System (ADS)

    Doennig, David; Pentcheva, Rossitza

    2015-01-01

    The diverse functionality emerging at oxide interfaces calls for a fundamental understanding of the mechanisms and control parameters of electronic reconstructions. Here, we explore the evolution of electronic phases in (LaAlO3)M/(SrTiO3)N (001) superlattices as a function of strain and confinement of the SrTiO3 quantum well. Density functional theory calculations including a Hubbard U term reveal a charge ordered Ti3+ and Ti4+ state for N = 2 with an unanticipated orbital reconstruction, displaying alternating dxz and dyz character at the Ti3+ sites, unlike the previously reported dxy state, obtained only for reduced c-parameter at aSTO. At aLAO c-compression leads to a Dimer-Mott insulator with alternating dxz, dyz sites and an almost zero band gap. Beyond a critical thickness of N = 3 (aSTO) and N = 4 (aLAO) an insulator-to-metal transition takes place, where the extra e/2 electron at the interface is redistributed throughout the STO slab with a dxy interface orbital occupation and a mixed dxz + dyz occupation in the inner layers. Chemical variation of the SrTiO3 counterpart (LaAlO3 vs. NdGaO3) proves that the significant octahedral tilts and distortions in the SrTiO3 quantum well are induced primarily by the electrostatic doping at the polar interface and not by variation of the SrTiO3 counterpart.

  17. METC/3M Cooperative Agreement CRADA 94-024 high temperature high pressure filter materials exposure test program. Volume 2, Final report

    SciTech Connect

    1995-06-01

    This report is a summary of the results of activities of the particulate monitoring group in support of the METC/3M CRADA 94024. Online particulate monitoring began in June 1994 and ended in October, 1994. The particulate monitoring group participated in four MGCR runs (No. 7 through No. 10). The instrument used in measuring the particle loadings (particle counts and size distribution) is the Particle Measuring Systems Classical Scattering Aerosol Spectrometer Probe High Temperature and High Pressure (PMS Model CSASP-100-HTHP). This PMS unit is rated to operate at temperatures up to 540{degree}C and gage pressures up to 2.0 MPa. Gas stream conditions, temperature at 540{degree}C, gage pressure at 2.93 MPa, and gas flowrate at 0.0157 SCM per second, precluded the direct measurement of particulate loadings in the gas stream with the PMS unit. A side stream was extracted from the gas stream after it came over to the MGCR, Modular Gas Cleanup Rig, from the FBG, pressurized Fluidized-Bed Gasifier, but before it entered the filter testing vessel. A sampling probe of 0.635 cm O.D. thin wall stainless steel tubing was used for extracting the sample gas isokinetically based on the expected flowrate. The sample gas stream was further split into two streams; one was directed to the PMS unit and the other to the alkali monitor unit. The alkali monitor unit was not used during runs No. 7 through No. 10.

  18. Formation of the bisulfite anion (HSO(3) (-) , m/z 81) upon collision-induced dissociation of anions derived from organic sulfonic acids.

    PubMed

    Jariwala, Freneil B; Wood, Ryan E; Nishshanka, Upul; Attygalle, Athula B

    2012-04-01

    In the negative-ion collision-induced dissociation mass spectra of most organic sulfonates, the base peak is observed at m/z 80 for the sulfur trioxide radical anion (SO(3) (-·) ). In contrast, the product-ion spectra of a few sulfonates, such as cysteic acid, aminomethanesulfonate, and 2-phenylethanesulfonate, show the base peak at m/z 81 for the bisulfite anion (HSO(3) (-) ). An investigation with an extensive variety of sulfonates revealed that the presence of a hydrogen atom at the β-position relative to the sulfur atom is a prerequisite for the formation of the bisulfite anion. The formation of HSO(3) (-) is highly favored when the atom at the β-position is nitrogen, or the leaving neutral species is a highly conjugated molecule such as styrene or acrylic acid. Deuterium-exchange experiments with aminomethanesulfonate demonstrated that the hydrogen for HSO(3) (-) formation is transferred from the β-position. The presence of a peak at m/z 80 in the spectrum of 2-sulfoacetic acid, in contrast to a peak at m/z 81 in that of 3-sulfopropanoic acid, corroborated the proposed hydrogen transfer mechanism. For diacidic compounds, such as 4-sulfobutanoic acid and cysteic acid, the m/z 81 ion can be formed by an alternative mechanism, in which the negative charge of the carboxylate moiety attacks the α-carbon relative to the sulfur atom. Experiments conducted with deuterium-exchanged and deuterium-labeled analogs of sulfocarboxylic acids demonstrated that the formation of the bisulfite anion resulted either from a hydrogen transfer from the β-carbon, or from a direct attack by the carboxylate moiety on the α-carbon.

  19. Photo-initiated thiol-ene click reactions as a potential strategy for incorporation of [M(I)(CO)3]+ (M = Re, (99m)Tc) complexes.

    PubMed

    Hayes, Thomas R; Lyon, Patrice A; Silva-Lopez, Elsa; Twamley, Brendan; Benny, Paul D

    2013-03-18

    Click reactions offer a rapid technique to covalently assemble two molecules. In radiopharmaceutical construction, these reactions can be utilized to combine a radioactive metal complex with a biological targeting molecule to yield a potent tool for imaging or therapy applications. The photo-initiated radical thiol-ene click reaction between a thiol and an alkene was examined for the incorporation of [M(I)(CO)3](+) (M = Re, (99m)Tc) systems for conjugating biologically active targeting molecules containing a thiol. In this strategy, a potent chelate system, 2,2'-dipicolylamine (DPA), for [M(I)(CO)3](+) was functionalized at the central amine with a terminal alkene linker that was explored with two synthetic approaches, click then chelate and chelate then click, to determine the flexibility and applicability of the thiol-ene click reaction to specifically incorporate ligand systems and metal complexes with a thiol containing molecule. In the click then chelate approach, the thiol-ene click reaction was carried out with the DPA chelate followed by complexation with [M(I)(CO)3](+). In the chelate then click approach, the alkene functionalized DPA chelate was first complexed with [M(I)(CO)3](+) followed by the conduction of the thiol-ene click reaction. Initial studies utilized benzyl mercaptan as a model thiol for both strategies to generate the identical product from either route to provide information on reactivity and product formation. DPA ligands functionalized with two unique linker systems (allyl and propyl allyl ether) were prepared to examine the effect of the proximity of the chelate or complex on the thiol-ene click reaction. Both the thiol-ene click and coordination reactions with Re, (99m)Tc were performed in moderate to high yields demonstrating the potential of the thiol-ene click reaction for [M(I)(CO)3](+) incorporation into thiol containing biomolecules.

  20. Synthesis and structure of In(IO{sub 3}){sub 3} and vibrational spectroscopy of M(IO{sub 3}){sub 3} (M=Al, Ga, In)

    SciTech Connect

    Ngo, Nhan; Kalachnikova, Katrina; Assefa, Zerihun; Haire, Richard G.; Sykora, Richard E. . E-mail: rsykora@jaguar1.usouthal.edu

    2006-12-15

    The reaction of Al, Ga, or In metals and H{sub 5}IO{sub 6} in aqueous media at 180{sup o}C leads to the formation of Al(IO{sub 3}){sub 3}, Ga(IO{sub 3}){sub 3,} or In(IO{sub 3}){sub 3}, respectively. Single-crystal X-ray diffraction experiments have shown In(IO{sub 3}){sub 3} contains the Te{sub 4}O{sub 9}-type structure, while both Al(IO{sub 3}){sub 3} and Ga(IO{sub 3}){sub 3} are known to exhibit the polar Fe(IO{sub 3}){sub 3}-type structure. Crystallographic data for In(IO{sub 3}){sub 3}, trigonal, space group R3-bar , a=9.7482(4)A, c=14.1374(6)A, V=1163.45(8) Z=6, R(F)=1.38% for 41 parameters with 644 reflections with I>2{sigma}(I). All three iodate structures contain group 13 metal cations in a distorted octahedral coordination environment. M(IO{sub 3}){sub 3} (M=Al, Ga) contain a three-dimensional network formed by the bridging of Al{sup 3+} or Ga{sup 3+} cations by iodate anions. With In(IO{sub 3}){sub 3}, iodate anions bridge In{sup 3+} cations in two-dimensional layers. Both materials contain distorted octahedral holes in their structures formed by terminal oxygen atoms from the iodate anions. The Raman spectra have been collected for these metal iodates; In(IO{sub 3}){sub 3} was found to display a distinctively different vibrational profile than Al(IO{sub 3}){sub 3} or Ga(IO{sub 3}){sub 3}. Hence, the Raman profile can be used as a rapid diagnostic tool to discern between the different structural motifs.

  1. Developmental regulation of collagenase-3 mRNA in normal, differentiating osteoblasts through the activator protein-1 and the runt domain binding sites

    NASA Technical Reports Server (NTRS)

    Winchester, S. K.; Selvamurugan, N.; D'Alonzo, R. C.; Partridge, N. C.

    2000-01-01

    Collagenase-3 mRNA is initially detectable when osteoblasts cease proliferation, increasing during differentiation and mineralization. We showed that this developmental expression is due to an increase in collagenase-3 gene transcription. Mutation of either the activator protein-1 or the runt domain binding site decreased collagenase-3 promoter activity, demonstrating that these sites are responsible for collagenase-3 gene transcription. The activator protein-1 and runt domain binding sites bind members of the activator protein-1 and core-binding factor family of transcription factors, respectively. We identified core-binding factor a1 binding to the runt domain binding site and JunD in addition to a Fos-related antigen binding to the activator protein-1 site. Overexpression of both c-Fos and c-Jun in osteoblasts or core-binding factor a1 increased collagenase-3 promoter activity. Furthermore, overexpression of c-Fos, c-Jun, and core-binding factor a1 synergistically increased collagenase-3 promoter activity. Mutation of either the activator protein-1 or the runt domain binding site resulted in the inability of c-Fos and c-Jun or core-binding factor a1 to increase collagenase-3 promoter activity, suggesting that there is cooperative interaction between the sites and the proteins. Overexpression of Fra-2 and JunD repressed core-binding factor a1-induced collagenase-3 promoter activity. Our results suggest that members of the activator protein-1 and core-binding factor families, binding to the activator protein-1 and runt domain binding sites are responsible for the developmental regulation of collagenase-3 gene expression in osteoblasts.

  2. Rhenium and technetium tricarbonyl, {M(CO)3} (+) (M = Tc, Re), binding to mammalian metallothioneins: new insights into chemical and radiopharmaceutical implications.

    PubMed

    Lecina, Joan; Palacios, Òscar; Atrian, Sílvia; Capdevila, Mercè; Suades, Joan

    2015-04-01

    This paper deals with the binding of the four mammalian metallothioneins (MTs) to the organometallic metal fragment {fac-M(CO)3}(+) (M = (99)Tc, Re), which is highly promising for the preparation of second-generation radiopharmaceuticals. The study of the transmetallation reaction between zinc and rhenium in Zn7-MT1 by means of UV-vis and CD spectroscopy demonstrated the incorporation of the {fac-Re(CO)3}(+) fragment to the MTs. This reaction should be performed at 70 °C to accelerate the reaction rate, a result that is consistent with the reported reactivity of the rhenium fragment. ESI-TOF MS demonstrated the formation of mixed-metal species as Zn6,{Re(CO)3}-MT, Zn6,{Re(CO)3}2-MT, and Zn5,{Re(CO)3}3-MT, as well as the different reactivity of the four MT isoforms. Hence, Zn-MT3 showed the highest reactivity, in agreement with its high Cu-thionein character, whereas Zn-MT2 exhibited the lowest reactivity, in line with its high Zn-thionein character. The reactivity of the Zn-loaded forms of MT1 and MT4 is intermediate between those of MT3 and MT2. The study of the binding of the {fac-(99)Tc(CO)3}(+) fragment to MTs showed a significant and very interesting different reactivity in relation to rhenium. The transmetallation reaction is much more effective with technetium than with rhenium and significant amounts of mixed Zn x ,{(99)Tc(CO)3} y -MT species were formed with the four MT isoforms whereas only MT3 rendered similar amounts of rhenium derivatives. The results obtained in this study support the possible use of technetium for labelling mammalian metallothioneins and also for possible radiopharmaceutical applications.

  3. Ba 3M IIITiM VO 9 (M III = Fe, Ga, Y, Lu; M V = Nb, Ta, Sb) perovskite oxides: Synthesis, structure and dielectric properties

    NASA Astrophysics Data System (ADS)

    Joy, Joby E.; Atamanik, Eric; Mani, Rohini; Nag, Abanti; Tiwari, R. M.; Thangadurai, V.; Gopalakrishnan, J.

    2010-12-01

    We describe the synthesis, structures and dielectric properties of new perovskite oxides of the formula, Ba 3M IIITiM VO 9, for M III = Fe, Ga, Y, Lu and M V = Nb, Ta, Sb. While M V = Nb and Ta oxides adopt disordered/partially ordered 3C perovskite structures where M III/Ti/M V metal-oxygen octahedra are corner-connected, the M V = Sb oxides show a distinct preference for the 6H structure, where Sb V/Ti IV metal-oxygen octahedra share a common face forming (Sb,Ti)O 9 dimers that are corner-connected to the M IIIO 6 octahedra. The preference of antimony oxides (Sb V:4d 10) for the 6H structure - which arises from a special Sb V-O chemical bonding that tends to avoid linear Sb-O-Sb linkages unlike Nb V/Ta V:d 0 atoms which prefer ˜180° Nb/Ta-O-Nb/Ta linkages - is consistent with the crystal chemistry of M V-O oxides in general. The dielectric properties reveal a significant difference among M III members. All the oxides with the 3C structure excepting those with M III = Fe show a normal low loss dielectric behaviour with ɛ = 20-60 in the temperature range 50-400 °C; the M III = Fe members with this structure (M V = Nb, Ta) display a relaxor-like ferroelectric behaviour with large ɛ values at frequencies ≤1 MHz (50-500 °C).

  4. Identifying fecal pollution sources using 3M(™) Petrifilm (™) count plates and antibiotic resistance analysis in the Horse Creek Watershed in Aiken County, SC (USA).

    PubMed

    Harmon, S Michele; West, Ryan T; Yates, James R

    2014-12-01

    Sources of fecal coliform pollution in a small South Carolina (USA) watershed were identified using inexpensive methods and commonly available equipment. Samples from the upper reaches of the watershed were analyzed with 3M(™) Petrifilm(™) count plates. We were able to narrow down the study's focus to one particular tributary, Sand River, that was the major contributor of the coliform pollution (both fecal and total) to a downstream reservoir that is heavily used for recreation purposes. Concentrations of total coliforms ranged from 2,400 to 120,333 cfu/100 mL, with sharp increases in coliform counts observed in samples taken after rain events. Positive correlations between turbidity and fecal coliform counts suggested a relationship between fecal pollution and stormwater runoff. Antibiotic resistance analysis (ARA) compared antibiotic resistance profiles of fecal coliform isolates from the stream to those of a watershed-specific fecal source library (equine, waterfowl, canines, and untreated sewage). Known fecal source isolates and unknown isolates from the stream were exposed to six antibiotics at three concentrations each. Discriminant analysis grouped known isolates with an overall average rate of correct classification (ARCC) of 84.3 %. A total of 401 isolates from the first stream location were classified as equine (45.9 %), sewage (39.4 %), waterfowl (6.2 %), and feline (8.5 %). A similar pattern was observed at the second sampling location, with 42.6 % equine, 45.2 % sewage, 2.8 % waterfowl, 0.6 % canine, and 8.8 % feline. While there were slight weather-dependent differences, the vast majority of the coliform pollution in this stream appeared to be from two sources, equine and sewage. This information will contribute to better land use decisions and further justify implementation of low-impact development practices within this urban watershed.

  5. High Precision Photometry of Variable Stars in Clusters of Different Ages with the 1.3 m Robotically Controlled Telescope (RCT)

    NASA Astrophysics Data System (ADS)

    Guinan, E. F.; McCook, G. P.; DeWarf, L. E.; Gelderman, R. F.; McGruder, C. H.; Walter, D. K.; Howell, S. B.; Davis, D. R.; Everett, M.; Mattox, J. R.

    2003-05-01

    We discuss a new program of carrying out high precision VRI CCD photometry of several star clusters of different ages. The photometry is being carried out using the 1.3 m Robotically Controlled Telescope (RCT), located at KPNO. This program focuses on the study of variable stars in mostly open clusters. Selected astrophysically important eclipsing binaries, pulsating variables, blue stragglers, and chromospherically active variable stars will be studied. Also, searches of new variable stars will be made from the expected large samples of cluster stars. For example, photometry is planned of the several W UMa eclipsing binaries and blue straggler stars in the old open cluster NGC 188. Photometry also will be carried out of the young open cluster NGC 7790. This cluster is unique because has three confirmed classical cepheid members: CE Cas A (V ˜ +10.9 mag; F8 Ib; P = 4.446 d ), CE Cep B (V ˜ +11.0 mag; F9 Ib; 5.128 d), and CF Cas (V ˜ +11.1 mag; F8 Ib; 4.875 d). NGC 7790 also contains the 10th mag eccentric B0+B0 eclipsing binary QX Cas. The observations of QX Cas are being conducted to determine the accurate distance to this star and thus to the cluster and its cepheid members. When complete these observations, combined with spectroscopy, will permit a reliable calibration of the ``zero-point'' of the galactic cepheid Period-Luminosity Law. Another possible project is the search of light variations of PMS stars and chromospherically active stars (from star spot rotational modulations) in young clusters such as the alpha Perseus Cluster, h & χ Per, M34, and the Pleiades. Refurbishment of the RCT has been made possible by NASA grant NAG 58762. The RCT Consortium includes: Western Kentucky Univ., S. Carolina St Univ., Francis Marion Univ., Villanova Univ., and the Planetary Science Institute (PSI).

  6. Control of orbital reconstruction in (LaAlO3)M/(SrTiO3)N(001) quantum wells by strain and confinement

    PubMed Central

    Doennig, David; Pentcheva, Rossitza

    2015-01-01

    The diverse functionality emerging at oxide interfaces calls for a fundamental understanding of the mechanisms and control parameters of electronic reconstructions. Here, we explore the evolution of electronic phases in (LaAlO3)M/(SrTiO3)N (001) superlattices as a function of strain and confinement of the SrTiO3 quantum well. Density functional theory calculations including a Hubbard U term reveal a charge ordered Ti3+ and Ti4+ state for N = 2 with an unanticipated orbital reconstruction, displaying alternating dxz and dyz character at the Ti3+ sites, unlike the previously reported dxy state, obtained only for reduced c-parameter at aSTO. At aLAO c-compression leads to a Dimer-Mott insulator with alternating dxz, dyz sites and an almost zero band gap. Beyond a critical thickness of N = 3 (aSTO) and N = 4 (aLAO) an insulator-to-metal transition takes place, where the extra e/2 electron at the interface is redistributed throughout the STO slab with a dxy interface orbital occupation and a mixed dxz + dyz occupation in the inner layers. Chemical variation of the SrTiO3 counterpart (LaAlO3 vs. NdGaO3) proves that the significant octahedral tilts and distortions in the SrTiO3 quantum well are induced primarily by the electrostatic doping at the polar interface and not by variation of the SrTiO3 counterpart. PMID:25601648

  7. Structural insights into M2O-Al2O3-WO3 (M = Na, K) system by electron diffraction tomography.

    PubMed

    Andrusenko, Iryna; Krysiak, Yaşar; Mugnaioli, Enrico; Gorelik, Tatiana E; Nihtianova, Diana; Kolb, Ute

    2015-06-01

    The M2O-Al2O3-WO3 (M = alkaline metals) system has attracted the attention of the scientific community because some of its members showed potential applications as single crystalline media for tunable solid-state lasers. These materials behave as promising laser host materials due to their high and continuous transparency in the wide range of the near-IR region. A systematic investigation of these phases is nonetheless hampered because it is impossible to produce large crystals and only in a few cases a pure synthetic product can be achieved. Despite substantial advances in X-ray powder diffraction methods, structure investigation on nanoscale is still challenging, especially when the sample is polycrystalline and the structures are affected by pseudo-symmetry. Electron diffraction has the advantage of collecting data from single nanoscopic crystals, but it is frequently limited by incompleteness and dynamical effects. Automated diffraction tomography (ADT) recently emerged as an alternative approach able to collect more complete three-dimensional electron diffraction data and at the same time to significantly reduce dynamical scattering. ADT data have been shown to be suitable for ab initio structure solution of phases with large cell parameters, and for detecting pseudo-symmetry that was undetected in X-ray powder data. In this work we present the structure investigation of two hitherto undetermined compounds, K5Al(W3O11)2 and NaAl(WO4)2, by a combination of electron diffraction tomography and precession electron diffraction. We also stress how electron diffraction tomography can be used to obtain direct information about symmetry and pseudo-symmetry for nanocrystalline phases, even when available only in polyphasic mixtures.

  8. Geometrical parameterization of the crystal chemistry of P6(3)/m apatites: comparison with experimental data and ab initio results.

    PubMed

    Mercier, Patrick H J; Le Page, Yvon; Whitfield, Pamela S; Mitchell, Lyndon D; Davidson, Isobel J; White, T J

    2005-12-01

    Experimental structure refinements and ab initio simulation results for 18 published, fully ordered P6(3)/m (A;{\\rm I}_4)(A;{\\rm II}_6)(BO4)6X2 apatite end-member compositions have been analyzed in terms of a geometric crystal-chemical model that allows the prediction of unit-cell parameters (a and c) and all atom coordinates. To an accuracy of +/- 0.025 A, the magnitude of c was reproduced from crystal-chemical parameters characterizing chains of ...-A(II)-O3-B-O3-A(II)-... atoms, whereas that of a was determined from those describing (A(I)O6)-(BO4) polyhedral arrangements. The c/a ratio could be predicted to +/-0.2% using multi-variable functions based on geometric crystal-chemical model predictions, but could not be ascribed to the adjustment of a single crystal-chemical parameter. The correlations observed between algebraically independent crystal-chemical parameters representing the main observed polyhedral distortions reveal them as the minimum-energy solution to accommodate misfit components within this flexible structure type. For materials with given composition, good agreement (within +/- 0.5-2.0%) of ab initio crystal-chemical parameters was observed with only those from single-crystal refinements with R 4.0% was not as good, while the scatter with those from Rietveld refinements was considerable. Accordingly, ab initio cell data, atomic coordinates and crystal-chemical parameters were reported here for the following compositions awaiting experimental work: (Zn,Hg)10(PO4)6(Cl,F)2, (Ca,Cd)10(VO4)6Cl2 and (Ca,Pb,Cd)10(CrO4)6Cl2.

  9. Decreased AMPA GluR2, but not GluR3, mRNA expression in rat amygdala and dorsal hippocampus following morphine-induced behavioural sensitization.

    PubMed

    Sepehrizadeh, Zargham; Bahrololoumi Shapourabadi, Mina; Ahmadi, Shamseddin; Hashemi Bozchlou, Saeed; Zarrindast, Mohammad-Reza; Sahebgharani, Mousa

    2008-11-01

    1. Repeated administration of psychostimulants and micro-opioid receptor agonists elicits a progressive enhancement of drug-induced behavioural responses, a phenomenon termed behavioural sensitization. These changes in behaviour may reflect plastic changes requiring regulation of alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid (AMPA) receptor function. 2. In the present study, rats were treated for 7 days with saline or morphine (10 mg/kg). After a washout period of either 24 h or 7 days, locomotion, oral stereotypy and state-dependent memory in a passive avoidance test were measured in the presence or absence of 6-cyano-7-nitroquinoxaline-2,3-dione disodium salt (CNQX; 3 mg/kg), an AMPA receptor antagonist. In order to evaluate the mechanism underlying the behavioural responses, quantitative real-time reverse transcription-polymerase chain reaction was used to evaluate mRNA expression of the AMPA receptor subunits GluR2 and GluR3 in the striatum, prefrontal cortex, hippocampus, hypothalamus and amygdala of animals treated repeatedly with morphine. 3. The results indicate that repeated morphine treatment followed by 7 days (but not 24 h) washout produces behavioural sensitization, as determined by locomotion, oral stereotypy and state-dependent memory. Blockade of AMPA receptors with CNQX on the test day did not alter these behavioural responses. In addition, repeated morphine treatment followed by 7 days (but not 24 h) washout decreased GluR2 mRNA expression in both the amygdala (by 50%) and hippocampus (by 35%). Repeated morphine treatment did not alter GluR3 mRNA expression in any brain area assessed. 4. These data imply that AMPA receptors are involved in the development (but not expression) phase of behavioural sensitization. The decreases in GluR2 mRNA expression in the amygdala and hippocampus may result in the formation of calcium-permeable AMPA receptors, which are believed to play an important role in behavioural sensitization.

  10. Zero thermal expansion and ferromagnetism in cubic Sc(1-x)M(x)F3 (M = Ga, Fe) over a wide temperature range.

    PubMed

    Hu, Lei; Chen, Jun; Fan, Longlong; Ren, Yang; Rong, Yangchun; Pan, Zhao; Deng, Jinxia; Yu, Ranbo; Xing, Xianran

    2014-10-01

    The rare physical property of zero thermal expansion (ZTE) is intriguing because neither expansion nor contraction occurs with temperature fluctuations. Most ZTE, however, occurs below room temperature. It is a great challenge to achieve isotropic ZTE at high temperatures. Here we report the unconventional isotropic ZTE in the cubic (Sc1-xMx)F3 (M = Ga, Fe) over a wide temperature range (linear coefficient of thermal expansion (CTE), αl = 2.34 × 10(-7) K(-1), 300-900 K). Such a broad temperature range with a considerably negligible CTE has rarely been documented. The present ZTE property has been designed using the introduction of local distortions in the macroscopic cubic lattice by heterogeneous cation substitution for the Sc site. Even though the macroscopic crystallographic structure of (Sc0.85Ga0.05Fe0.1)F3 adheres to the cubic system (Pm3̅m) according to the results of X-ray diffraction, the local structure exhibits a slight rhombohedral distortion. This is confirmed by pair distribution function analysis of synchrotron radiation X-ray total scattering. This local distortion may weaken the contribution from the transverse thermal vibration of fluorine atoms to negative thermal expansion, and thus may presumably be responsible for the ZTE. In addition, the present ZTE compounds of (Sc1-xMx)F3 can be functionalized to exhibit high-Tc ferromagnetism and a narrow-gap semiconductor feature. The present study shows the possibility of obtaining ZTE materials with multifunctionality in future work.

  11. Molten Ga as a solvent for exploratory synthesis. Preparation, structure, and properties of two ternary silicides MNiSi{sub 3} (M = Sm, Y)

    SciTech Connect

    Chen, X.Z.; Larson, P.; Sportouch, S.; Mahanti, S.D.; Kanatzidis, M.G.; Brazis, P.; Kannewurf, C.R.

    1999-01-01

    Two ternary silicides, MNiSi{sub 3} (M = Sm, Y), have been synthesized from Sm, Ni, and Si in molten Ga at 850 C in sealed silica tubes. Both compounds form black shiny crystals and are stable even in aqua regia. The structures, determined by single-crystal X-ray diffraction, are orthorhombic, Cmmm (No. 65) with Z = 4, and have lattice parameters a = 3.965(2) {angstrom}, b = 21.144(2) {angstrom}, c = 4.007(1) {angstrom} for M = Sm and a = 3.930(2) {angstrom}, b = 21.021(2) {angstrom}, c = 3.960(1) {angstrom} for M = Y, respectively. Refinement based on F{sub o}{sup 2} yielded R{sub 1} = 0.0319 and wR{sub 2} = 0.0712 [I > 2 {sigma}(I)] for M = Sm and R{sub 1} = 0.0267 and wR{sub 2} = 0.0688 [I > 2{sigma}(I)] for M = Y. The compounds adopt the SmNiGe{sub 3} structure type with zigzag Si chains and Si dimers and exhibit metallic p-type electrical conductivity. Variable temperature magnetic susceptibility data suggest that Sm is 3+ and Ni has no magnetic moment. SmNiSi{sub 3} has an antiferromagnetic transition at 12 K and follows the modified Curie-Weiss law above 12 K. Band structure calculations using density functional theory, generalized gradient approximation, full potential LAPW method, and also extended Hueckel tight binding theory show that the materials are metallic and suggest that Ni is either neutral or in a reduced oxidation state. Additional insight into the bonding was obtained by extended Hueckel calculations carried out on the [NiSi{sub 3}]{sup 3{minus}} framework under the assumption that Y is mostly 3+. These results suggest that the Si zigzag chain contains single bonds with a partial double bond character.

  12. 1,2-Ethanediol and 1,3-Propanediol Conversions over (MO3)3 (M = Mo, W) Nanoclusters: A Computational Study.

    PubMed

    Fang, Zongtang; Zetterholm, Patrick; Dixon, David A

    2016-03-24

    The dehydration and dehydrogenation reactions of one and two 1,2-ethanediol and 1,3-propanediol molecules on (MO3)3 (M = Mo, W) nanoclusters have been studied computationally using density functional and coupled cluster (CCSD(T)) theory. The reactions are initiated by the formation of a Lewis acid-base complex with an additional hydrogen bond. Dehydration is the dominant reaction proceeding via a metal bisdiolate. Acetaldehyde, the major product for 1,2-ethanediol, is produced by α-hydrogen transfer from one CH2 group to the other. For 1,3-propanediol, the C-C bond breaking pathways to produce C2H4 and HCH═O simultaneously and proton transfer to generate propylene oxide have comparable barrier energies. The barrier to produce propanal from the propylene oxide complex is less than that for epoxide release from the cluster. On the Mo3O9 cluster, a redox reaction channel for 1,2-ethanediol to break the C-C bond to form two formaldehyde molecules and then to produce C2H4 is slightly more favorable than the formation of acetaldehyde. For W(VI), the energy barrier for the reduction pathway is larger due to the lower reducibility of W3O9. Similar reduction on Mo(VI) for 1,3-propanediol to form propene is not a favorable pathway compared with the other pathways as additional C-H bond breaking is required in addition to breaking a C-C bond. The dehydrogenation and dehydration activation energies for the selected glycols are larger than the reactions of ethanol and 1-propanol on the same clusters. The CCSD(T) method is required because density functional theory with the M06 and B3LYP functionals does not predict quantitative energies on the potential energy surface. The M06 functional performs better than does the B3LYP functional.

  13. Alkaline Earth Metal Zirconate Perovskites MZrO3 (M=Ba(2+), Sr(2+), Ca(2+)) Derived from Molecular Precursors and Doped with Eu(3+) Ions.

    PubMed

    Drąg-Jarząbek, Anna; John, Łukasz; Petrus, Rafał; Kosińska-Klähn, Magdalena; Sobota, Piotr

    2016-03-24

    The effect of alkaline earth metal alkoxides on the protonation of zirconocene dichloride was investigated. This approach enabled the design of compounds with preset molecular structures for generating high-purity binary metal oxide perovskites MZrO3 (M=Ba(2+), Sr(2+), Ca(2+)). Single-source molecular precursors [Ba4 Zr2 (μ6 -O)(μ3 ,η(2)-OR)8 (OR)2(η(2) -HOR)2 (HOR)2 Cl4], [Sr4 Zr2 (μ6 -O)(μ3 ,η(2)-OR)8 (OR)2 (HOR)4 Cl4], [Ca4 Zr2 (μ6-O)(μ3 ,η(2)-OR)8 (OR)2 Cl4], and [Ca6 Zr2 (μ2 ,η(2)-OR)12 (μ-Cl)2 (η(2) -HOR)4 Cl6 ]⋅8 CH2 Cl2 were prepared via elimination of the cyclopentadienyl ring from Cp2 ZrCl2 as CpH in the presence of M(OR)2 and alcohol ROH (ROH=CH3OCH2 CH2OH) as a source of protons. The resulting complexes were characterized by elemental analysis, IR and NMR spectroscopy, and single-crystal X-ray diffraction. The compounds were then thermally decomposed to MCl2 /MZrO3 mixtures. Leaching of MCl2 from the raw powder with deionized water produced highly pure perovskite-like oxide particles of 40-80 nm in size. Luminescence studies on Eu(3+)-doped MZrO3 revealed that the perovskites are attractive host lattices for potential applications in display technology.

  14. Hydrothermal carbonization of anaerobically digested maize silage.

    PubMed

    Mumme, Jan; Eckervogt, Lion; Pielert, Judith; Diakité, Mamadou; Rupp, Fabian; Kern, Jürgen

    2011-10-01

    Hydrochars were prepared by hydrothermal carbonization (HTC) of maize silage previously treated at 55 °C in a two-stage solid-state reactor system. The HTC was carried out in a 1-L stirred pressure reactor with pH regulation by citric acid. The treated silage carbonized at relatively mild conditions (190 °C, 2 h), and the hydrochars showed mainly amorphous macro-size features with a carbon content of 59-79% (ash-free, dry) and a higher heating value of 25-36 MJ kg⁻¹. Temperature was the main influencing factor. The surface area according to Brunauer-Emmett-Teller (BET) analysis was highest at 190 °C (12.3 m²) g⁻¹). Based on these results, the hydrochars are potentially interesting for applications such as an alternative fuel or a soil conditioner.

  15. Carbon particles

    DOEpatents

    Hunt, Arlon J.

    1984-01-01

    A method and apparatus whereby small carbon particles are made by pyrolysis of a mixture of acetylene carried in argon. The mixture is injected through a nozzle into a heated tube. A small amount of air is added to the mixture. In order to prevent carbon build-up at the nozzle, the nozzle tip is externally cooled. The tube is also elongated sufficiently to assure efficient pyrolysis at the desired flow rates. A key feature of the method is that the acetylene and argon, for example, are premixed in a dilute ratio, and such mixture is injected while cool to minimize the agglomeration of the particles, which produces carbon particles with desired optical properties for use as a solar radiant heat absorber.

  16. Carbon tetrachloride

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 08 / 005F www.epa.gov / iris TOXICOLOGICAL REVIEW OF CARBON TETRACHLORIDE ( CAS No . 56 - 23 - 5 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) March 2010 U.S . Environmental Protection Agency Washington , DC ii DISCLAIMER This document has bee

  17. Carbon disulfide

    Integrated Risk Information System (IRIS)

    Carbon disulfide ; CASRN 75 - 15 - 0 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 E

  18. The 1.3-m Robotically Controlled Telescope (RCT) at Kitt Peak - A Fifty year old dream Realized: Telescope Characteristics, Current Research and Education Progr

    NASA Astrophysics Data System (ADS)

    Guinan, Edward; Gelderman, Richard; Strolger, Louis-Gregory; Carini, Michael T.; McGruder, Charles, III; Campbell, Rachel; Walter, Donald K.; Davis, Donald R.; Tedesco, Edward F.; Engle, Scott G.

    2011-03-01

    The 1.3 m Robotically Controlled Telescope (RCT) on Kitt Peak has a rich history, including its role as a prototype for remotely controlled telescopes during the 1960s. As such, the RCT could be considered one of the first - Telescopes from Afar. The telescope, originally called the Remotely Controlled Telescope, has been renamed the Robotically Controlled Telescope to reflect the change in operational control and mode of use. The RCT was a conceptual precursor of today's robotic telescopes, but the actual operation of a remotely controlled telescope was technologically premature for its time, and was subsequently manually operated primarily to conduct optical and infrared observations as well being used as a test bed for new spectroscopic and photometric instruments. In 1995 budget constraints forced the closing of the telescope as part of the Kitt Peak National Observatory (KPNO), following nearly 30 years of distinguished service to KPNO. A request for proposals to operate this telescope was issued to the science community. The RCT consortium, lead by Western Kentucky University, was the successful proposer for operation of the telescope. After several difficult years of retrofitting, refurbishing, and automating the telecope and observatory dome, the telescope has returned to routine science operations in November 2009. The RCT has operated smoothly since that time, with no major interruptions. Observations of objects of interest to the consortium partners (including: comets & asteroids, variable & binary stars, exoplanets, supernovae, quasars & blazars) are being routinely obtained and evaluated. One of the distinguishing features of the RCT is that it is an autonomous observatory designed to handle diverse optical imaging and photometry programs. These include being able to automatically deal with a wide range of observing parameters such as -integration time, sky conditions, repetitions, return visits, filters, air mass, non-sidereal objects, transients etc

  19. BTG/Tob family members Tob1 and Tob2 inhibit proliferation of mouse embryonic stem cells via Id3 mRNA degradation

    SciTech Connect

    Chen, Yuanfan; Wang, Chenchen; Wu, Jenny; Li, Lingsong

    2015-07-03

    The mammalian BTG/Tob family is a group of proteins with anti-proliferative ability, and there are six members including BTG1, BTG2/PC3/Tis21, BTG3/ANA, BTG4/PC3B, Tob1/Tob and Tob2. Among them, Tob subfamily members, specifically Tob1/Tob and Tob2, have the most extensive C-terminal regions. As previously reported, overexpression of BTG/Tob proteins is associated with the inhibition of G1 to S-phase cell cycle progression and decreased cell proliferation in a variety of cell types. Tob subfamily proteins have similar anti-proliferative effects on cell cycle progression in cultured tumor cells. An important unresolved question is whether or not they have function in rapidly proliferating cells, such as embryonic stem cells (ESCs). Tob1 and Tob2 were expressed ubiquitously in mouse ESCs (mESCs), suggesting a possible role in early embryonic development and mESCs. To address the above question and explore the possible functions of the Tob subfamily in ESCs, we established ESCs from different genotypic knockout inner cell mass (ICM). We found that Tob1{sup −/−}, Tob2{sup −/−}, and Tob1/2 double knockout (DKO, Tob1{sup −/−} & Tob2{sup −/−}) ESCs grew faster than wild type (WT) ESCs without losing pluripotency, and we provide a possible mechanistic explanation for these observations: Tob1 and Tob2 inhibit the cell cycle via degradation of Id3 mRNA, which is a set of directly targeted genes of BMP4 signaling in mESCs that play critical roles in the maintenance of ESC properties. Together, our data suggest that BTG/Tob family protein Tob1 and Tob2 regulation cell proliferation does not compromise the basic properties of mESCs. - Highlights: • We established mouse Tob1/2 double knockout embryonic stem cells. • Tob1 and Tob2 inhibit the proliferation of ESCs without effect on pluripotency. • Tob1 and Tob2 involved in the degradation of Id3 in mESCs.

  20. Elastic relaxations associated with the Pm3m-R3c transition in LaA103 III: superattenuation of acoustic resonances

    SciTech Connect

    Darling, Timothy W; Carpenter, M A; Buckley, A; Taylor, P A; Mcknight, R E A

    2009-01-01

    Resonant Ultrasound Spectroscopy has been used to characterize elastic softening and a variety of new acoustic dissipation processes associated with the Pm{bar 3}m {leftrightarrow} R{bar 3}c transition in single crystal and ceramic samples of LaAlO{sub 3}. Softening of the cubic structure ahead of the transition point is not accompanied by an increase in dissipation but follows different temperature dependences for the bulk modulus, 1/3(C{sub 11} + 2C{sub 12}), and the shear components 1/2(C{sub 11}-C{sub 12}) and C{sub 44} as if the tilting instability contains two slightly different critical temperatures. The transition itself is marked by the complete disappearance of resonance peaks (superattenuation), which then reappear below {approx}700 K in spectra from single crystals. Comparison with low frequency, high stress data from the literature indicate that the dissipation is not due to macroscopic displacement of needle twins. An alternative mechanism, local bowing of twin walls under low dynamic stress, is proposed. Pinning of the walls with respect to this displacement process occurs below {approx}350 K. Anelasticity maps, analogous to plastic deformation mechanism maps, are proposed to display dispersion relations and temperature/frequency/stress fields for different twin wall related dissipation mechanisms. An additional dissipation process, with an activation energy of 43 {+-} 6 kJ.mole{sup -1}, occurs in the vicinity of 250 K. The mechanism for this is not known, but it is associated with C{sub 44} and therefore appears to be related in some way to the cubic {leftrightarrow} rhombohedral transition at {approx}817 K. Slight softening in the temperature interval {approx}220 {yields} 70 K of resonance peaks determined by shear elastic constants hints at an incipient E{sub g} ferroelastic instability in LaAlO{sub 3}. The softening interval ends with a further dissipation peak at {approx} 60 K, the origin of which is discussed in terms of freezing of atomic

  1. FOXP3 mRNA expression at 6 months of age is higher in infants who develop atopic dermatitis, but is not affected by giving probiotics from birth.

    PubMed

    Taylor, Angie L; Hale, Jasmine; Hales, Belinda J; Dunstan, Janet A; Thomas, Wayne R; Prescott, Susan L

    2007-02-01

    Factors that influence immune regulation in early life may be implicated in the rise in allergic disease, including reduced microbial burden. The aim of the study was to examine the infant regulatory T-cell function in relation to (a) probiotic supplementation for the first 6 months of life and (b) the subsequent development of an early allergic phenotype. Two hundred and thirty-one allergic, pregnant women were recruited into a randomized, controlled trial. The infants received either a probiotic or placebo daily for the first 6 months of life. One hundred and seventy-eight children completed the study, with blood samples available from 118 (60 placebo; 58 probiotic). CD4(+)CD25(+)CTLA4(+)T-regulatory phenotype and allergen-induced FOXP3 mRNA expression were compared in relation to this intervention as well as according to evidence of early disease (atopic dermatitis). The administration of probiotics was not associated with any significant differences in the proportion of circulating CD4(+)CD25(+)CTLA4(+)cells, or in the resting expression of FOXP3. There were also no relationships between these parameters and patterns of gut colonization, and this probiotic did not reduce the risk of atopic dermatitis. Children who developed atopic dermatitis (n = 36/118) had significantly higher induced FOXP3 expression following stimulation with both house dust mite (HDM) (p = 0.017) and ovalbumin (OVA) allergens (p = 0.021) than those that did not develop atopic dermatitis. Although this relationship was seen in both the probiotic and placebo groups, it was more pronounced in the probiotic group. However, regression analysis demonstrated that higher allergen-induced FOXP3 expression was predicted by the presence of atopic dermatitis (p = 0.018) rather than probiotics supplementation (p = 0.217). The higher levels of allergen-induced FOXP3 in atopic dermatitis suggest activation of these compensatory mechanisms rather than a primary defect in this pathway. Probiotic

  2. Carbon-carbon - An overview

    NASA Technical Reports Server (NTRS)

    Buckley, John D.

    1988-01-01

    In nonoxidizing high-temperature environments, carbon-carbon composites retain room temperature properties to more than 2225 C; in oxidizing environments, the variety of coatings thus far developed limits maximum operating temperatures to about 1600 C. The high thermal conductivity and low thermal expansion of these composites renders them ideal for applications encountering thermal shocks. In addition, the variety of fibers, weave patterns, and layup procedures that can be used for the composites allows mechanical properties to be carefully tailored over a wide range to fit the application in question.

  3. Carbon Pneumoconiosis

    PubMed Central

    Miller, A. A.; Ramsden, F.

    1961-01-01

    The occurrence of carbon pneumoconiosis in rubber-factory workers is unusual: the case reported here was discovered in a routine post-mortem examination. The report includes the clinical, radiological, morbid anatomical, and histological findings on a man who had worked in the carbon black store of a rubber works for a continuous period of 21 years, followed by 11 years in the calender department of the same factory. At the age of 65 years the man was retired on the grounds of age and indifferent health: he collapsed and died soon afterwards. The medical history of severe cough with expectoration suggested that he may have had pulmonary tuberculosis in earlier life and some supporting evidence of this infection was found in that his wife contracted this disease after marriage and subsequently died from tuberculosis. The appearances of massive fibrosis in the upper lobes of the lungs suggested that the combined action of carbon black and tuberculosis had produced an “infective” type of pneumoconiosis: in the lower lobes there was far less fibrosis and the appearances were those of simple pneumoconiosis. In addition to the fibrosis the lungs showed nodules of black dust with severe perifocal emphysema. Electron microscopy of the lung dust showed two distinct components and they were similar to samples of channel and thermal blacks which were the main types of carbon used in the factory. This case is an example of pneumoconiosis due to virtually non-siliceous carbon and illustrates that prolonged exposure to heavy dust concentration produces such lesions as described in this paper. Images PMID:13770721

  4. The effect of additives on the reactivity of palladium surfaces for the chemisorption and hydrogenation of carbon monoxide: A surface science and catalytic study. [LaMO/sub 3/(M = Cr, Mn, Fe, Co, Rh)

    SciTech Connect

    Rucker, T.G.

    1987-06-01

    This research studied the role of surface additives on the catalytic activity and chemisorptive properties of Pd single crystals and foils. Effects of Na, K, Si, P, S, and Cl on the bonding of CO and H and on the cyclotrimerization of acetylene on the (111), (100) and (110) faces of Pd were investigated in addition to role of TiO/sub 2/ and SiO/sub 2/ overlayers deposited on Pd foils in the CO hydrogenation reaction. On Pd, only in the presence of oxide overlayers, are methane or methanol formed from CO and H/sub 2/. The maximum rate of methane formation is attained on Pd foil where 30% of the surface is covered with titania. Methanol formation can be achieved only if the TiO/sub x//Pd surface is pretreated in 50 psi of oxygen at 550/sup 0/C prior to the reaction. The additives (Na, K, Si, P, S, Cl) affect the bonding of CO and hydrogen and the cyclotrimerization of acetylene to benzene by structural and electronic interactions. In general, the electron donating additives increase the desorption temperature of CO and increase the rate of acetylene cyclotrimerization and the electron withdrawing additives decrease the desorption temperature of CO and decrease the rate of benzene formation from acetylene.

  5. What Have We Learned About Arctic Carbon Since The First State of the Carbon Cycle Report?

    NASA Astrophysics Data System (ADS)

    Schuur, E.

    2015-12-01

    Large pools of organic carbon were reported in The First State of the Carbon Cycle Report, but measurements from high latitude ecosystems, in particular for deeper soils >1m depth, remained scarce. A newly enlarged soil carbon database with an order of magnitude more numerous deep sampling sites has verified the widespread pattern of large quantities of carbon accumulated deep in permafrost (perennially frozen) soils. The known pool of permafrost carbon across the northern circumpolar permafrost zone is now estimated to be 1330-1580 Pg C, with the potential for an additional ~400 Pg C in deep permafrost sediments. In addition, an uncertainty estimate of plus/minus 15% has now been calculated for the soil carbon pool in the surface 0-3m. Laboratory incubations of these permafrost soils reveal that a significant fraction can be mineralized by microbes upon thaw and converted to carbon dioxide and methane on time scales of years to decades, with decade-long average losses from aerobic incubations ranging from 6-34% of initial carbon. Carbon emissions from the same soils incubated in an anaerobic environment are, on average, 78-85% lower than aerobic soils. But, the more potent greenhouse gas methane released under anaerobic conditions in part increases the climate impact of these emissions. While mean quantities of methane are only 3% to 7% that of carbon dioxide emitted from anaerobic incubations (by weight of C), these mean methane values represent 25% to 45% of the overall potential impact on climate when accounting for the higher global warming potential of methane. Taken together though, in spite of the more potent greenhouse gas methane, a unit of newly thawed permafrost carbon could have a greater impact on climate over a century if it thaws and decomposes within a drier, aerobic soil as compared to an equivalent amount of carbon within a waterlogged soil or sediment. Model projections tend to estimate losses of carbon in line with empirical measurements, but

  6. CARBONATE METHOD OF SEPARATION OF TETRAVALENT PLUTONIUM FROM FISSION PRODUCT VALUES

    DOEpatents

    Duffield, R.B.; Stoughton, R.W.

    1959-02-01

    It has been found that plutonium forms an insoluble precipitate with carbonate ion when the carbonate ion is present in stoichiometric proportions, while an excess of the carbonate ion complexes plutonium and renders it soluble. A method for separating tetravalent plutonium from lanthanum-group rare earths has been based on this discovery, since these rare earths form insoluble carbonates in approximately neutral solutions. According to the process the pH is adjusted to between 5 and 7, and approximately stoichiometric amounts of carbonate ion are added to the solution causing the formation of a precipitate of plutonium carbonate and the lanthanum-group rare earth carbonates. The precipitate is then separated from the solution and contacted with a carbonate solution of a concentration between 1 M and 3 M to complex and redissolve the plutonium precipitate, and thus separate it from the insoluble rare earth precipitate.

  7. Barium carbonate catalysis of carbon gasification

    SciTech Connect

    Ersolmaz, C.; Falconer, J.L.

    1985-01-01

    The interaction of barium carbonate with carbon black was studied to understand catalyzed CO/sub 2/ gasification of carbon. Temperature-programmed reaction with isotopic labeling of the carbonate and the carbon showed that carbon dramatically accelerated with rate of BaCO/sub 3/ decomposition to form BaO and CO/sub 2/, which rapidly gasified carbon to form CO. Pure BaCO/sub 3/ was observed to exchange carbon dioxide with the gas-phase, and the exchange rate was significantly increased by carbon at higher temperatures, due to formation of a carbon-carbonate complex. The interaction of BaCO/sub 3/ and C to form a complex occurred well below gasification temperatures, and BaCO/sub 3/ did not decompose until after gasification began and the gas phase CO/sub 2/ concentration was low.

  8. Clickable, hydrophilic ligand for fac-[M(I)(CO)3](+) (M = Re/(99m)Tc) applied in an S-functionalized α-MSH peptide.

    PubMed

    Kasten, Benjamin B; Ma, Xiaowei; Liu, Hongguang; Hayes, Thomas R; Barnes, Charles L; Qi, Shibo; Cheng, Kai; Bottorff, Shalina C; Slocumb, Winston S; Wang, Jing; Cheng, Zhen; Benny, Paul D

    2014-03-19

    The copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction was used to incorporate alkyne-functionalized dipicolylamine (DPA) ligands (1 and 3) for fac-[M(I)(CO)3](+) (M = Re/(99m)Tc) complexation into an α-melanocyte stimulating hormone (α-MSH) peptide analogue. A novel DPA ligand with carboxylate substitutions on the pyridyl rings (3) was designed to increase the hydrophilicity and to decrease in vivo hepatobiliary retention of fac-[(99m)Tc(I)(CO)3](+) complexes used in single photon emission computed tomography (SPECT) imaging studies with targeting biomolecules. The fac-[Re(I)(CO)3(3)] complex (4) was used for chemical characterization and X-ray crystal analysis prior to radiolabeling studies between 3 and fac-[(99m)Tc(I)(OH2)3(CO)3](+). The corresponding (99m)Tc complex (4a) was obtained in high radiochemical yields, was stable in vitro for 24 h during amino acid challenge and serum stability assays, and showed increased hydrophilicity by log P analysis compared to an analogous complex with nonfunctionalized pyridine rings (2a). An α-MSH peptide functionalized with an azide was labeled with fac-[M(I)(CO)3](+) using both click, then chelate (CuAAC reaction with 1 or 3 followed by metal complexation) and chelate, then click (metal complexation of 1 and 3 followed by CuAAC with the peptide) strategies to assess the effects of CuAAC conditions on fac-[M(I)(CO)3](+) complexation within a peptide framework. The peptides from the click, then chelate strategy had different HPLC tR's and in vitro stabilities compared to those from the chelate, then click strategy, suggesting nonspecific coordination of fac-[M(I)(CO)3](+) using this synthetic route. The fac-[M(I)(CO)3](+)-complexed peptides from the chelate, then click strategy showed >90% stability during in vitro challenge conditions for 6 h, demonstrated high affinity and specificity for the melanocortin 1 receptor (MC1R) in IC50 analyses, and led to moderately high uptake in B16F10 melanoma cells

  9. A novel, cysteine-modified chelation strategy for the incorporation of [MI(CO)3]+ (M = Re, 99mTc) in an α-MSH peptide

    PubMed Central

    Jiang, Han; Kasten, Benjamin B.; Liu, Hongguang; Qi, Shibo; Liu, Yang; Tian, Mei; Barnes, Charles L.; Zhang, Hong; Cheng, Zhen; Benny, Paul D.

    2012-01-01

    Engineering peptide-based targeting agents with residues for site specific and stable complexation of radionuclides is a highly desirable strategy for producing diagnostic and therapeutic agents for cancer and other diseases. In this report, a model N-S-NPy ligand (3) and a cysteine-derived alpha-melanocyte stimulating hormone (α-MSH) peptide (6) were used as novel demonstrations of a widely applicable chelation strategy for incorporation of the [MI(CO)3]+ (M = Re, 99mTc) core into peptide-based molecules for radiopharmaceutical applications. The structural details of the core ligand-metal complexes as model systems were demonstrated by full chemical characterization of fac-[ReI(CO)3(N,S,NPy-3)]+ (4) and comparative high performance liquid chromatography (HPLC) analysis between 4 and [99mTcI(CO)3(N,S,NPy-3)]+ (4a). The α-MSH analogue bearing the N-S-NPy chelate on a modified cysteine residue (6) was generated and complexed with [MI(CO)3]+ to confirm the chelation strategy’s utility when applied in a peptide-based targeting agent. Characterization of the ReI(CO)3-6 peptide conjugate (7) confirmed the efficient incorporation of the metal center, and the 99mTcI(CO)3-6 analogue (7a) was explored as a potential single photon emission computed tomography (SPECT) compound for imaging the melanocortin 1 receptor (MC1R) in melanoma. Peptide 7a showed excellent radiolabeling yields and in vitro stability during amino acid challenge and serum stability assays. In vitro B16F10 melanoma cell uptake of 7a reached a modest value of 2.3 ± 0.08% of applied activity at 2 h at 37 °C while this uptake was significantly reduced by coincubation with a nonlabeled α-MSH analogue, NAPamide (3.2 µM) (P < 0.05). In vivo SPECT/X-ray computer tomography (SPECT/CT) imaging and biodistribution of 7a were evaluated in a B16F10 melanoma xenografted mouse model. SPECT/CT imaging clearly visualized the tumor at 1 h post injection (p.i.) with high tumor-to-background contrast. Blocking

  10. IC Engine Applications of Carbon-Carbon

    NASA Technical Reports Server (NTRS)

    Northam, G. Burton; Rivers, H. Kevin

    2000-01-01

    Many of the properties of carbon-carbon make it an ideal material for reciprocating materials of intermittent combustion (IC) engines. Recent diesel engine tests, shown herein, indicate that the thermal and mechanical properties of carbon-carbon are adequate for piston applications, However, reducing the manufacturing costs and providing long term oxidation protection are still issues that need to be addressed.

  11. Filament Winding Of Carbon/Carbon Structures

    NASA Technical Reports Server (NTRS)

    Jacoy, Paul J.; Schmitigal, Wesley P.; Phillips, Wayne M.

    1991-01-01

    Improved method of winding carbon filaments for carbon/carbon composite structures less costly and labor-intensive, also produces more consistent results. Involves use of roller squeegee to ensure filaments continuously wet with resin during winding. Also involves control of spacing and resin contents of plies to obtain strong bonds between carbon filaments and carbon matrices. Lends itself to full automation and involves use of filaments and matrix-precursor resins in their simplest forms, thereby reducing costs.

  12. Carbonic inclusions

    NASA Astrophysics Data System (ADS)

    Van den Kerkhof, Alfons; Thiéry, Régis

    2001-01-01

    The paper gives an overview of the phase relations in carbonic fluid inclusions with pure, binary and ternary mixtures of the system CO 2-CH 4-N 2, compositions, which are frequently found in geological materials. Phase transitions involving liquid, gas and solid phases in the temperature range between -192°C and 31°C are discussed and presented in phase diagrams ( PT, TX and VX projections). These diagrams can be applied for the interpretation of microthermometry data in order to determine fluid composition and molar volume (or density).

  13. Carbon Nanomembranes.

    PubMed

    Turchanin, Andrey; Gölzhäuser, Armin

    2016-08-01

    Carbon nanomembranes (CNMs) are synthetic 2D carbon sheets with tailored physical or chemical properties. These depend on the structure, molecular composition, and surroundings on either side. Due to their molecular thickness, they can be regarded as "interfaces without bulk" separating regions of different gaseous, liquid, or solid components and controlling the materials exchange between them. Here, a universal scheme for the fabrication of 1 nm-thick, mechanically stable, functional CNMs is presented. CNMs can be further modified, for example perforated by ion bombardment or chemically functionalized by the binding of other molecules onto the surfaces. The underlying physical and chemical mechanisms are described, and examples are presented for the engineering of complex surface architectures, e.g., nanopatterns of proteins, fluorescent dyes, or polymer brushes. A simple transfer procedure allows CNMs to be placed on various support structures, which makes them available for diverse applications: supports for electron and X-ray microscopy, nanolithography, nanosieves, Janus nanomembranes, polymer carpets, complex layered structures, functionalization of graphene, novel nanoelectronic and nanomechanical devices. To close, the potential of CNMs in filtration and sensorics is discussed. Based on tests for the separation of gas molecules, it is argued that ballistic membranes may play a prominent role in future efforts of materials separation.

  14. Sequestering ADM ethanol plant carbon dioxide

    USGS Publications Warehouse

    Finley, R.J.; Riddle, D.

    2008-01-01

    Archer Daniels Midland Co. (ADM) and the Illinois State Geological Survey (ISGS) are collaborating on a project in confirming that a rock formation can store carbon dioxide from the plant in its pores. The project aimed to sequester the gas underground permanently to minimize release of the greenhouse gas into the atmosphere. It is also designed to store one million tons of carbon dioxide over a three-year period. The project is worth $84.3M, funded by $66.7M from the US Department Energy, supplemented by co-funding from ADM and other corporate and state resources. The project will start drilling of wells to an expected depth over 6500 feet into the Mount Simon Sandstone formation.

  15. Trading forest carbon

    EPA Science Inventory

    The nature of carbon in forests is discussed from the perspective of carbon trading. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Carbon turnover in forests is discussed as it relates to carbon sequestration. Scient...

  16. Interfaces in carbon-carbon composites

    SciTech Connect

    Peebles, L.H.; Meyer, R.A.; Jortner, J.

    1988-01-01

    Carbon-carbon composites, consisting of a carbon matrix reinforced with carbon fibers, have complex microstructures. Several types of interfaces, microcracks, and various degress of local anisotropy were observed. This paper provides examples of microstructures seen in carbon-carbon composites, with emphasis on the interfaces. Information relating to the degree of bonding at interfaces, and its effects on composite behavior, is reviewed. The causes and effects of the various observed microstructures are beginning to be understood, but there remain many questions deserving further study.

  17. Effect of gold subsurface layer on the surface activity and segregation in Pt/Au/Pt{sub 3}M (where M = 3d transition metals) alloy catalyst from first-principles

    SciTech Connect

    Kim, Chang-Eun; Lim, Dong-Hee; Jang, Jong Hyun; Kim, Hyoung Juhn; Yoon, Sung Pil; Han, Jonghee; Nam, Suk Woo; Hong, Seong-Ahn; Soon, Aloysius E-mail: hchahm@kist.re.kr; Ham, Hyung Chul E-mail: hchahm@kist.re.kr

    2015-01-21

    The effect of a subsurface hetero layer (thin gold) on the activity and stability of Pt skin surface in Pt{sub 3}M system (M = 3d transition metals) is investigated using the spin-polarized density functional theory calculation. First, we find that the heterometallic interaction between the Pt skin surface and the gold subsurface in Pt/Au/Pt{sub 3}M system can significantly modify the electronic structure of the Pt skin surface. In particular, the local density of states projected onto the d states of Pt skin surface near the Fermi level is drastically decreased compared to the Pt/Pt/Pt{sub 3}M case, leading to the reduction of the oxygen binding strength of the Pt skin surface. This modification is related to the increase of surface charge polarization of outmost Pt skin atoms by the electron transfer from the gold subsurface atoms. Furthermore, a subsurface gold layer is found to cast the energetic barrier to the segregation loss of metal atoms from the bulk (inside) region, which can enhance the durability of Pt{sub 3}M based catalytic system in oxygen reduction condition at fuel cell devices. This study highlights that a gold subsurface hetero layer can provide an additional mean to tune the surface activity toward oxygen species and in turn the oxygen reduction reaction, where the utilization of geometric strain already reaches its practical limit.

  18. Longitudinal studies of patients with ANCA vasculitis demonstrate concurrent reactivity to complementary PR3 protein segments cPR3m and cPR3C and with no reactivity to cPR3N

    PubMed Central

    Hewins, Peter; Belmonte, Frances; Jennette, J Charles; Falk, Ronald J; Preston, Gloria A

    2010-01-01

    Antibodies recognizing the complement of the middle of PR3 (cPR3m) occur in ~30% of PR3-ANCA-vasculitis patients and immunization of animals with a peptide complementary to the middle of PR3 (cPR3m) induces not only anti-complementary PR3 antibodies, but also anti-PR3 antibodies derived through an anti-idiotypic response. PR3 epitopes recognized by patient ANCA however, are not restricted to the middle of PR3. This prompted us to test for antibodies that react with proteins complementary to the terminal regions of PR3 (cPR3C and cPR3N) in PR3-ANCA patients. Anti-cPR3C reactivity was detected in 28% of patients but anti-cPR3N reactivity in only 15%. Ranked anti-cPR3C and anti-cPR3m reactivity correlated in the cohort, whereas there was no significant relationship between cPR3C and cPR3N reactivity. Serial samples from three patients’ revealed that anti-cPR3C and anti-cPR3m reactivity followed a similar pattern over time. Serial samples from a fourth patient demonstrated an anti-cPR3N response without concurrent cPR3m or cPR3C reactivity. Epitope determination by mass spectrometry identified a thirteen amino acid sequence on cPR3C that contained a common binding site recognized by antibodies from three patients. This peptide sequence contains a “PHQ” motif which was reported to be the basis for cross-reactivity of anti-cPR3m antibodies with plasminogen. Why these antibodies are detected in only ~30% of the patients remains unclear. The data reveal it is not due to lack of inclusion of flanking regions of complementary PR3 during screening. Instead, quite unexpectedly, the data demonstrate that patients’ antibodies react with a restricted epitope that exists in both cPR3m and cPR3C. PMID:20712431

  19. Carbon Farming as a Carbon Negative Technology

    NASA Astrophysics Data System (ADS)

    Anderson, C.; Laird, D.; Hayes, D. J.

    2015-12-01

    Carbon farms have a pivotal role in national and international efforts to mitigate and adapt to climate change. A carbon farm in its broadest sense is one that reduces greenhouse gas (GHG) emissions or captures and holds carbon in vegetation and soils. Their capacity to remove carbon from the air and store it safely and permanently, while providing additional human and ecosystem benefits, means they could contribute significantly to national efforts to stabilize or reduce GHGs. We examine carbon farms in the context of corn and soybean production agriculture. We illustrate, using Iowa data but with relevance across United States corn and soybean production, the potential for carbon farms to reduce human GHG emissions and sequester carbon permanently at a rate that has meaningful impact on global greenhouse gas concentration. Carbon has been viewed as a next generation cash crop in Iowa for over a decade. The carbon farm perspective, however, goes beyond carbon as cash crop to make carbon the center of an entire farm enterprise. The transformation is possible through slight adjustment crop practices mixed with advances in technology to sequester carbon through biochar. We examine carbon balance of Iowa agriculture given only the combination of slight reduction in fertilizer and sequestration by biochar. We find the following. Iowa carbon farms could turn Iowa agriculture into a carbon sink. The estimated range of GHG reduction by statewide implementation of carbon farms is 19.46 to 90.27 MMt CO2-equivalent (CO2-e), while the current agricultural CO2-e emission estimate is 35.38 MMt CO2-e. Iowa carbon farm GHG reduction would exceed Iowa GHG reduction by wind energy (8.7 MMt CO2-e) and could exceed combined reductions from wind energy and corn grain ethanol (10.7 MMt CO2-e; 19.4 MMt CO2-e combined). In fact, Iowa carbon farms alone could exceed GHG reduction from national corn grain ethanol production (39.6 MMt CO2-e). A carbon price accessible to agricultural

  20. Carbon dioxide concentrator

    NASA Technical Reports Server (NTRS)

    Williams, C. F.; Huebscher, R. G.

    1972-01-01

    Passed exhaled air through electrochemical cell containing alkali metal carbonate aqueous solution, and utilizes platinized electrodes causing reaction of oxygen at cathode with water in electrolyte, producing hydroxyl ions which react with carbon dioxide to form carbonate ions.

  1. Method of making carbon-carbon composites

    DOEpatents

    Engle, Glen B.

    1993-01-01

    A process for making 2D and 3D carbon-carbon composites having a combined high crystallinity, high strength, high modulus and high thermal and electrical conductivity. High-modulus/high-strength mesophase derived carbon fibers are woven into a suitable cloth. Layers of this easily graphitizible woven cloth are infiltrated with carbon material to form green composites. The carbonized composite is then impregnated several times with pitch by covering the composite with hot pitch under pressure. The composites are given a heat treatment between each impregnant step to crack up the infiltrated carbon and allow additional pitch to enter the microstructure during the next impregnation cycle. The impregnated composites are then given a final heat treatment in the range 2500.degree. to 3100.degree. C. to fully graphitize the fibers and the matrix carbon. The composites are then infiltrated with pyrolytic carbon by chemical vapor deposition in the range 1000.degree. C. to 1300.degree. C. at a reduced. pressure.

  2. Integral Ring Carbon-Carbon Piston

    NASA Technical Reports Server (NTRS)

    Northam, G. Burton (Inventor)

    1999-01-01

    An improved structure for a reciprocating internal combustion engine or compressor piston fabricate from carbon-carbon composite materials is disclosed. An integral ring carbon-carbon composite piston, disclosed herein, reduces the need for piston rings and for small clearances by providing a small flexible, integral component around the piston that allows for variation in clearance due to manufacturing tolerances, distortion due to pressure and thermal loads, and variations in thermal expansion differences between the piston and cylinder liner.

  3. Carbon Capture (Carbon Cycle 2.0)

    ScienceCinema

    Smit, Berend

    2016-07-12

    Berend Smit speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 3, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

  4. Carbon-carbon grid for ion engines

    NASA Technical Reports Server (NTRS)

    Garner, Charles E. (Inventor)

    1995-01-01

    A method and apparatus of manufacturing a grid member for use in an ion discharge apparatus provides a woven carbon fiber in a matrix of carbon. The carbon fibers are orientated to provide a negatibe coefficient of thermal expansion for at least a portion of the grid member's operative range of use.

  5. Carbon-carbon grid for ion engines

    NASA Technical Reports Server (NTRS)

    Garner, Charles E. (Inventor)

    1993-01-01

    A method and apparatus of manufacturing a grid member for use in an ion discharge apparatus provides a woven carbon fiber in a matrix of carbon. The carbon fibers are orientated to provide a negatibe coefficient of thermal expansion for at least a portion of the grid member's operative range of use.

  6. Composite carbon foam electrode

    DOEpatents

    Mayer, S.T.; Pekala, R.W.; Kaschmitter, J.L.

    1997-05-06

    Carbon aerogels used as a binder for granulated materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivity and power to system energy. 1 fig.

  7. Composite carbon foam electrode

    DOEpatents

    Mayer, Steven T.; Pekala, Richard W.; Kaschmitter, James L.

    1997-01-01

    Carbon aerogels used as a binder for granularized materials, including other forms of carbon and metal additives, are cast onto carbon or metal fiber substrates to form composite carbon thin film sheets. The thin film sheets are utilized in electrochemical energy storage applications, such as electrochemical double layer capacitors (aerocapacitors), lithium based battery insertion electrodes, fuel cell electrodes, and electrocapacitive deionization electrodes. The composite carbon foam may be formed by prior known processes, but with the solid particles being added during the liquid phase of the process, i.e. prior to gelation. The other forms of carbon may include carbon microspheres, carbon powder, carbon aerogel powder or particles, graphite carbons. Metal and/or carbon fibers may be added for increased conductivity. The choice of materials and fibers will depend on the electrolyte used and the relative trade off of system resistivty and power to system energy.

  8. Carbon Nanomembranes

    NASA Astrophysics Data System (ADS)

    Angelova, Polina; Gölzhäuser, Armin

    2017-03-01

    This chapter describes the formation and properties of one nanometer thick carbon nanomembranes (CNMs), made by electron induced cross-linking of aromatic self-assembled monolayers (SAMs). The cross-linked SAMs are robust enough to be released from the surface and placed on solid support or over holes as free-standing membranes. Annealing at 1000K transforms CNMs into graphene accompanied by a change of mechanical stiffness and electrical resistance. The developed fabrication approach is scalable and provides molecular level control over thickness and homogeneity of the produced CNMs. The mechanisms of electron-induced cross-linking process are discussed in details. A variety of polyaromatic thiols: oligophenyls as well as small and extended condensed polycyclic hydrocarbons have been successfully employed, demonstrating that the structural and functional properties of the resulting nanomembranes are strongly determined by the structure of molecular monolayers. The mechanical properties of CNMs (Young's modulus, tensile strength and prestress) are characterized by bulge testing. The interpretation of the bulge test data relates the Young's modulus to the properties of single molecules and to the structure of the pristine SAMs. The gas transport through the CNM is measured onto polydimethylsiloxane (PDMS) - thin film composite membrane. The established relationship of permeance and molecular size determines the molecular sieving mechanism of permeation through this ultrathin sheet.

  9. Carbon in, Carbon out: Reevaluating Carbon Fluxes in Subduction Zones

    NASA Astrophysics Data System (ADS)

    Manning, C. E.; Kelemen, P. B.

    2015-12-01

    Subduction zones exert a fundamental control on the deep carbon cycle. We reevaluated carbon inputs and outputs in convergent margins considering new estimates of C concentration in subducting mantle peridotites, carbonate solubility in aqueous fluids along subduction geotherms, melting and diapirism of carbon-bearing metasediments, and diffuse degassing from arcs. Our updated estimate of carbon inputs to the global subduction system, which includes estimates for C in altered peridotite, is 40-66 megatons carbon/year (MtC/y). We find that estimates of C lost from slabs (14-66 MtC/y) must take into account the high CaCO3 solubility in aqueous fluids, which contributes significant C that must be added to that derived from mineral decarbonation reactions. When taken together with hydrous silicate and carbonatite melts and metasediment diapirs, nearly all C can be scavenged from subducting lithosphere. The return of C to the atmosphere via arc-volcano degassing is only 18-43 MtC/y, but consideration deep volatile saturation of arc magmas, magma ponding in the middle and deep arc crust, and CO2 venting in forearcs can account for the remaining C lost from the slab. Thus, whereas previous studies concluded that about half the subducting carbon is returned to the convecting mantle, we find that relatively little carbon may be recycled. If so, substantial quantities of carbon are stored in the mantle lithosphere and crust and the carbon content of the mantle lithosphere + crust + ocean + atmosphere must be increasing, at least over the last 5-10 My. This is consistent with inferences from noble gas data. Recycled carbon in diamonds is a small fraction of the global carbon inventory.

  10. Acetylenic carbon allotrope

    DOEpatents

    Lagow, Richard J.

    1998-01-01

    A fourth allotrope of carbon, an acetylenic carbon allotrope, is described. The acetylenic carbon allotropes of the present invention are more soluble than the other known carbon allotropes in many common organic solvents and possesses other desirable characteristics, e.g. high electron density, ability to burn cleanly, and electrical conductive properties. Many uses for this fourth allotrope are described herein.

  11. Acetylenic carbon allotrope

    DOEpatents

    Lagow, Richard J.

    1999-01-01

    A fourth allotrope of carbon, an acetylenic carbon allotrope, is described. The acetylenic carbon allotropes of the present invention are more soluble than the other known carbon allotropes in many common organic solvents and possesses other desirable characteristics, e.g. high electron density, ability to burn cleanly, and electrical conductive properties. Many uses for this fourth allotrope are described herein.

  12. Petroleum-derived carbons

    SciTech Connect

    Bacha, J.D.; Newman, J.W.; White, J.L.

    1986-01-01

    This book presents the papers given at a symposium on petroleum coke. Topics considered at the symposium included mesophase formation, thermal analysis, rheology, microstructure, carbon fibers, electron microscopy, residual oil processing, synthetic aromatic pitch, delayed coking, calcination, desulfurization, graphite, metallurgical coke, carbon black, natural gas pyrolysis, liquid impregnation, and carbon-carbon composites.

  13. Carbon nanotube composite materials

    DOEpatents

    O'Bryan, Gregory; Skinner, Jack L; Vance, Andrew; Yang, Elaine Lai; Zifer, Thomas

    2015-03-24

    A material consisting essentially of a vinyl thermoplastic polymer, un-functionalized carbon nanotubes and hydroxylated carbon nanotubes dissolved in a solvent. Un-functionalized carbon nanotube concentrations up to 30 wt % and hydroxylated carbon nanotube concentrations up to 40 wt % can be used with even small concentrations of each (less than 2 wt %) useful in producing enhanced conductivity properties of formed thin films.

  14. Synthesis and Characterization of Et2NM OB[Si(OtBu)3]2 3 (M=Zr,Hf) Molecular Precursors to Zr/B/Si/O and Hf/B/Si/O Materials

    SciTech Connect

    Fujdala, Kyle L.; Tilley, T. Don

    2005-03-18

    Two new transition metal complexes containing the -OB[OSi(OtBu)3]2 ligand, Et2NM{l_brace}OB[OSi(OtBu)3]2{r_brace}3 (M = Zr, Hf), are reported. These species are the 4th and 5th examples of complexes containing this recently reported borosiloxide ligand. Their use as potential molecular precursors to multi-component oxide materials via the thermolytic molecular precursor (TMP) method is discussed.

  15. Comparison of 3M Petrifilm Aerobic Count Plates to standard plating methodology for use with AOAC antimicrobial efficacy methods 955.14, 955.15, 964.02, and 966.04 as an alternative enumeration procedure: collaborative study.

    PubMed

    Nelson, Maria T; LaBudde, Robert A; Tomasino, Stephen F; Pines, Rebecca M

    2013-01-01

    A multilaboratory study was conducted to determine the equivalence of the 3M Petrifilm Aerobic Count Plate and standard plating methodology for measuring viable bacteria and spores recovered from hard-surface carriers (stainless steel and porcelain), also known as "control carrier counts," used in AOAC antimicrobial efficacy test methods. Six laboratories participated in the study in which carriers inoculated with Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, and spores of Bacillus subtilis were evaluated using 3M Petrifilm Aerobic Count (AC) plates and standard plating side-by-side. The data were analyzed using a matched-pair t-test to determine the between-method effect with confidence intervals. For all test organisms pooled across all laboratories, the mean difference in log10 concentration between the standard plate count method and 3M Petrifilm AC Plates was -0.012, with a 95% confidence interval of (-0.090, +0.066), which was well within the -0.5, +0.5 interval established as the acceptance criterion. The between-carrier SD averaged 0.139; the between-replicate SD was 0.050. The carrier reproducibility, given that a single replicate per carrier is done, was estimated to be 0.148. Although differences were seen in the final concentrations of the test organisms among laboratories, there were no statistical differences between the enumeration methods. Based on the results from this study, 3M Petrifilm AC Plates are equivalent to standard plating methodology and can be used as an alternative procedure for the enumeration of test organisms used in AOAC Methods 955.14, 955.15, 964.02, and 966.04.

  16. Chemical Lead Optimization of a pan Gq mAChR M1, M3, M5 Positive Allosteric Modulator (PAM) Lead. Part II. Development of potent and highly selective M1 PAM

    PubMed Central

    Bridges, Thomas M.; Kennedy, J. Phillip; Noetzel, Meredith J.; Breininger, Micah L.; Gentry, Patrick R.; Conn, P. Jeffrey

    2010-01-01

    This Letter describes a chemical lead optimization campaign directed at VU0119498, a pan Gq mAChR M1, M3, M5 positive allosteric modulator (PAM) with the goal of developing a selective M1 PAM. An iterative library synthesis approach delivered a potent (M1 EC50 = 830 nM) and highly selective M1 PAM (>30 μM vs. M2-M5). PMID:20156687

  17. Automotive high color carbon

    SciTech Connect

    Ducote, R.E.; Dees, R.G.; Musick, V.L.

    1988-06-14

    A method of making a low porosity carbon black is described comprising: (1) feeding into a carbon black reactor a carbonaceous feed; (2) contacting the feed in the reactor with combustion gases containing oxygen thereby cracking the feed to produce carbon black; and (3) contacting the produced carbon black in the reactor with vaporizable hydrocarbon oil injected into the reaction at a point where the carbon black forming reaction is substantially complete to at least partially quench the carbon black producing reaction, the vaporizable hydrocarbon oil being cracked and serving to plate the carbon black to reduce the porosity thereof.

  18. Mesoporous carbon materials

    DOEpatents

    Dai, Sheng; Fulvio, Pasquale Fernando; Mayes, Richard T.; Wang, Xiqing; Sun, Xiao-Guang; Guo, Bingkun

    2014-09-09

    A conductive mesoporous carbon composite comprising conductive carbon nanoparticles contained within a mesoporous carbon matrix, wherein the conductive mesoporous carbon composite possesses at least a portion of mesopores having a pore size of at least 10 nm and up to 50 nm, and wherein the mesopores are either within the mesoporous carbon matrix, or are spacings delineated by surfaces of said conductive carbon nanoparticles when said conductive carbon nanoparticles are fused with each other, or both. Methods for producing the above-described composite, devices incorporating them (e.g., lithium batteries), and methods of using them, are also described.

  19. Pyrolyzed thin film carbon

    NASA Technical Reports Server (NTRS)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  20. PUFFER: Withstands 3-m drop (Mars gravity)

    NASA Video Gallery

    Pop-Up Flat Folding Explorer Robots, or PUFFER, is a small, origami-inspired robotic technology under development to provide a low-volume, low-cost mission enhancement for accessing new science fro...

  1. A 3M high temperature dielectric film

    NASA Technical Reports Server (NTRS)

    Hampl, Edward, Jr.

    1994-01-01

    The performance characteristics of a dielectric film are summarized. Additionally, the film's environmental and chemical properties are listed: low shrinkage to 300 C; moisture insensitive; low outgassing under vacuum; excellent surface qualities--easy metallization of film; flame retardant; and low smoke generation. A series of graphs that display the performance characteristics of the film are also presented.

  2. Carbon-coated LiFePO4-porous carbon composites as cathode materials for lithium ion batteries.

    PubMed

    Ni, Haifang; Liu, Jinkun; Fan, Li-Zhen

    2013-03-07

    This work introduces a facile strategy for the synthesis of carbon-coated LiFePO(4)-porous carbon (C-LiFePO(4)-PC) composites as a cathode material for lithium ion batteries. The LiFePO(4) particles obtained are about 200 nm in size and homogeneously dispersed in porous carbon matrix. These particles are further coated with the carbon layers pyrolyzed from sucrose. The C-LiFePO(4)-PC composites display a high initial discharge capacity of 152.3 mA h g(-1) at 0.1 C, good cycling stability, as well as excellent rate capability (112 mA h g(-1) at 5 C). The likely contributing factors to the excellent electrochemical performance of the C-LiFePO(4)-PC composites could be related to the combined effects of enhancement of conductivity by the porous carbon matrix and the carbon coating layers. It is believed that further carbon coating is a facile and effective way to improve the electrochemical performance of LiFePO(4)-PC.

  3. High Thermal Conductivity Carbon/Carbon Composites.

    DTIC Science & Technology

    1995-09-30

    The objective of this project was to develop a lowcost, high thermal conductivity carbon/carbon composite with a mesophase pitch -based matrix. A low...carbonization technique and heat treatment of the mesophase pitch was utilized to enhance composite properties by increasing the composite density...Three different fibers, T300 PAN-based, P55 pitch -based, and an experimental high thermal conductivity mesophase pitch -based, were incorporated as the

  4. Carbon fuel cells with carbon corrosion suppression

    DOEpatents

    Cooper, John F [Oakland, CA

    2012-04-10

    An electrochemical cell apparatus that can operate as either a fuel cell or a battery includes a cathode compartment, an anode compartment operatively connected to the cathode compartment, and a carbon fuel cell section connected to the anode compartment and the cathode compartment. An effusion plate is operatively positioned adjacent the anode compartment or the cathode compartment. The effusion plate allows passage of carbon dioxide. Carbon dioxide exhaust channels are operatively positioned in the electrochemical cell to direct the carbon dioxide from the electrochemical cell.

  5. Metallic carbon materials

    DOEpatents

    Cohen, Marvin Lou; Crespi, Vincent Henry; Louie, Steven Gwon Sheng; Zettl, Alexander Karlwalter

    1999-01-01

    Novel metallic forms of planar carbon are described, as well as methods of designing and making them. Nonhexagonal arrangements of carbon are introduced into a graphite carbon network essentially without destroying the planar structure. Specifically a form of carbon comprising primarily pentagons and heptagons, and having a large density of states at the Fermi level is described. Other arrangements of pentagons and heptagons that include some hexagons, and structures incorporating squares and octagons are additionally disclosed. Reducing the bond angle symmetry associated with a hexagonal arrangement of carbons increases the likelihood that the carbon material will have a metallic electron structure.

  6. Influence of cysteine doping on photoluminescence intensity from semiconducting single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Kurnosov, N. V.; Leontiev, V. S.; Linnik, A. S.; Karachevtsev, V. A.

    2015-03-01

    Photoluminescence (PL) from semiconducting single-walled carbon nanotubes can be applied for detection of cysteine. It is shown that cysteine doping (from 10-8 to 10-3 M) into aqueous suspension of nanotubes with adsorbed DNA leads to increase of PL intensity. The PL intensity was enhanced by 27% at 10-3 M cysteine concentration in suspension. Most likely, the PL intensity increases due to the passivation of p-defects on the nanotube by the cysteine containing reactive thiol group. The effect of doping with other amino acids without this group (methionine, serine, aspartic acid, lysine, proline) on the PL intensity is essentially weaker.

  7. Engineering α4β2 nAChRs with reduced or increased nicotine sensitivity via selective disruption of consensus sites in the M3-M4 cytoplasmic loop of the α4 subunit

    PubMed Central

    Biaggi-Labiosa, Nilza M.; Avilés-Pagán, Emir; Caballero-Rivera, Daniel; Báez-Pagán, Carlos; Lasalde-Dominicci, José A.

    2015-01-01

    The α4β2 neuronal nicotinic acetylcholine receptor (nAChR) plays a crucial role in nicotine addiction. These receptors are known to desensitize and up-regulate after chronic nicotine exposure, but the mechanism remains unknown. Currently, the structure and functional role of the intracellular domains of the nAChR are obscure. To study the effect of subunit phosphorylation on α4β2 nAChR function and expression, eleven residues located in the M3-M4 cytoplasmic loop were mutated to alanine and aspartic acid. Two-electrode voltage clamp and 125I-labeled epibatidine binding assays were performed on Xenopus oocytes to assess agonist activation and receptor expression. When ACh was used as an agonist, a decrease in receptor activation was observed for the majority of the mutations. When nicotine was used as an agonist, four mutations exhibited a statistically significant hypersensitivity to nicotine (S438D, S469A, Y576A, and S589A). Additionally, two mutations (S516D and T536A) that displayed normal activation with ACh displayed remarkable reductions in sensitivity to nicotine. Binding assays revealed a constitutive up-regulation in these two nicotine mutations with reduced nicotine sensitivity. These results suggest that consensus phosphorylation residues in the M3-M4 cytoplasmic loop of the α4 subunit play a crucial role in regulating α4β2 nAChR agonist selectivity and functional expression. Furthermore, these results suggest that disruption of specific interactions at PKC putative consensus sites can render α4β2 nAChRs almost insensitive to nicotine without substantial effects on normal AChR function. Therefore, these PKC consensus sites in the M3-M4 cytoplasmic loop of the α4 nAChR subunit could be a target for smoking cessation drugs. PMID:25957813

  8. Peroxisome proliferator-activated receptor alpha (PPARalpha) activators, bezafibrate and Wy-14,643, increase uncoupling protein-3 mRNA levels without modifying the mitochondrial membrane potential in primary culture of rat preadipocytes.

    PubMed

    Cabrero, A; Alegret, M; Sánchez, R; Adzet, T; Laguna, J C; Vázquez, M

    2000-08-15

    Uncoupling proteins (UCPs) are inner mitochondrial membrane transporters which act as pores for H(+) ions, dissipating the electrochemical gradient that develops during mitochondrial respiration at the expense of ATP synthesis. We have studied the effects of two fibrates, bezafibrate and Wy-14,643, on UCP-3 and UCP-2 mRNA levels in primary monolayer cultures of rat adipocytes and undifferentiated preadipocytes. Treatment with both PPARalpha activators for 24 h up-regulated UCP-3 mRNA levels. Thus, bezafibrate treatment resulted in an 8-fold induction in UCP-3 mRNA levels in preadipocytes compared with the 3.5-fold induction observed in adipocytes. Differences in the induction of UCP-3 between these cells correlated well with the higher expression of PPARalpha and RXRalpha mRNA values in preadipocytes compared to adipocytes. Wy-14,643 caused similar effects on UCP-3 mRNA expression. In contrast to UCP-3, UCP-2 mRNA levels were only slightly modified by bezafibrate in adipocytes. The induction in UCP-3 expression was not accompanied by changes in the mitochondrial membrane potential of rat primary preadipocytes after bezafibrate or Wy-14,643 treatment. Since it has been proposed that UCP-3 could be involved in the regulation of the use of fatty acids as fuel substrates, the UCP-3 induction achieved after bezafibrate and Wy-14, 643 treatment may indicate a higher oxidation of fatty acids, limiting their availability to be stored as triglycerides. This change may result in a reduced rate of conversion of preadipocytes to adipocytes, which directly affects fat depots.

  9. Engineering α4β2 nAChRs with reduced or increased nicotine sensitivity via selective disruption of consensus sites in the M3-M4 cytoplasmic loop of the α4 subunit.

    PubMed

    Biaggi-Labiosa, Nilza M; Avilés-Pagán, Emir; Caballero-Rivera, Daniel; Báez-Pagán, Carlos A; Lasalde-Dominicci, José A

    2015-12-01

    The α4β2 neuronal nicotinic acetylcholine receptor (nAChR) plays a crucial role in nicotine addiction. These receptors are known to desensitize and up-regulate after chronic nicotine exposure, but the mechanism remains unknown. Currently, the structure and functional role of the intracellular domains of the nAChR are obscure. To study the effect of subunit phosphorylation on α4β2 nAChR function and expression, eleven residues located in the M3-M4 cytoplasmic loop were mutated to alanine and aspartic acid. Two-electrode voltage clamp and 125I-labeled epibatidine binding assays were performed on Xenopus oocytes to assess agonist activation and receptor expression. When ACh was used as an agonist, a decrease in receptor activation was observed for the majority of the mutations. When nicotine was used as an agonist, four mutations exhibited a statistically significant hypersensitivity to nicotine (S438D, S469A, Y576A, and S589A). Additionally, two mutations (S516D and T536A) that displayed normal activation with ACh displayed remarkable reductions in sensitivity to nicotine. Binding assays revealed a constitutive up-regulation in these two nicotine mutations with reduced nicotine sensitivity. These results suggest that consensus phosphorylation residues in the M3-M4 cytoplasmic loop of the α4 subunit play a crucial role in regulating α4β2 nAChR agonist selectivity and functional expression. Furthermore, these results suggest that disruption of specific interactions at PKC putative consensus sites can render α4β2 nAChRs almost insensitive to nicotine without substantial effects on normal AChR function. Therefore, these PKC consensus sites in the M3-M4 cytoplasmic loop of the α4 nAChR subunit could be a target for smoking cessation drugs.

  10. Electrochemical capacitor improvement fabricated by carbon microfiber composite with admicellar-modified carbon nanotube

    NASA Astrophysics Data System (ADS)

    Pongprayoon, Thirawudh; Ayutthaya, Montira Seneewong-Na; Poochai, Chatwarin

    2017-02-01

    Conventional electrochemical capacitors are usually made from activated carbon microfiber electrode, which has relatively low electrochemical capacitance. To improve performance of electrochemical capacitor, carbon nanotube (CNT) was used to incorporate in carbon microfiber. Firstly, CNT was coated with ultra-thin polyacrylonitrile (PAN) film coating using the admicellar polymerization technique to improve its dispersion in PAN matrix. Secondly, the mix solution of admicellar-modified CNT (Ad-CNT) and PAN in N,N-dimethylformamide (DMF) was prepared to produce microfiber by electrospinning. Lastly, microfiber was collected as a sheet, which was then stabilized and carbonized to be used as an electrode. The fabricated electrode using Ad-CNT/PAN was analyzed by SEM and TEM. SEM images show that the microfiber was uniform with approximately 2 μm average diameter. TEM images display well alignment and good dispersion of Ad-CNT in the matrix. The electrode made from Ad-CNT/PAN exhibited a high specific capacitance of 125 F g-1 at a scan rate of 3 mV s-1 (based on cyclic voltammetry) and 82 F g-1 at a specific current of 1 A g-1 (based on galvanostatic charge/discharge). The percentage of relative specific capacitance retention of the prepared electrode was 70% after 1000 cycles. The results clearly show that the Ad-CNT played an effective role in improving dispersion in electrode leading to increase in electrical conductivity as well as electrical capacitance of the capacitor.

  11. Fertilization increases paddy soil organic carbon density.

    PubMed

    Wang, Shao-xian; Liang, Xin-qiang; Luo, Qi-xiang; Fan, Fang; Chen, Ying-xu; Li, Zu-zhang; Sun, Huo-xi; Dai, Tian-fang; Wan, Jun-nan; Li, Xiao-jun

    2012-04-01

    Field experiments provide an opportunity to study the effects of fertilization on soil organic carbon (SOC) sequestration. We sampled soils from a long-term (25 years) paddy experiment in subtropical China. The experiment included eight treatments: (1) check, (2) PK, (3) NP, (4) NK, (5) NPK, (6) 7F:3M (N, P, K inorganic fertilizers+30% organic N), (7) 5F:5M (N, P, K inorganic fertilizers+50% organic N), (8) 3F:7M (N, P, K inorganic fertilizers+70% organic N). Fertilization increased SOC content in the plow layers compared to the non-fertilized check treatment. The SOC density in the top 100 cm of soil ranged from 73.12 to 91.36 Mg/ha. The SOC densities of all fertilizer treatments were greater than that of the check. Those treatments that combined inorganic fertilizers and organic amendments had greater SOC densities than those receiving only inorganic fertilizers. The SOC density was closely correlated to the sum of the soil carbon converted from organic amendments and rice residues. Carbon sequestration in paddy soils could be achieved by balanced and combined fertilization. Fertilization combining both inorganic fertilizers and organic amendments is an effective sustainable practice to sequestrate SOC.

  12. Nonlinear transonic Wall-Interference Assessment/Correction (WIAC) procedures and application to cast-10 airfoil results from the NASA 0.3-m TCT 8- by 24-inch Slotted Wall Test Section (SWTS)

    NASA Technical Reports Server (NTRS)

    Gumbert, Clyde R.; Green, Lawrence L.; Newman, Perry A.

    1989-01-01

    From the time that wind tunnel wall interference was recognized to be significant, researchers have been developing methods to alleviate or account for it. Despite the best effort so far, it appears that no method is available which completely eliminates the effects due to the wind tunnel walls. This report discusses procedures developed for slotted wall and adaptive wall test sections of the Langley 0.3-m Transonic Cryogenic Tunnel (TCT) to assess and correct for the residual interference by methods consistent with the transonic nature of the tests.

  13. Method of making carbon-carbon composites

    SciTech Connect

    Engle, G.B.

    1991-10-29

    A process is described for making a carbon-carbon composite having a combination of high crystallinity, high strength, high modulus and high thermal and electrical conductivity. High-modulus/high-strength mesophase derived carbon fibers are woven into a suitable cloth. Layers of this easily graphitizable woven cloth are covered with petroleum or coal tar pitch and pressed at a temperature a few degrees above the softening point of the pitch to form a green laminated composite. The green composite is restrained in a suitable fixture and heated slowly to carbonize the pitch binder. The carbonized composite is then impregnated several times with pitch by covering the composite with hot pitch under pressure. The composites are given a heat treatment between each impregnation step to crack up the infiltrated carbon and allow additional pitch to enter the microstructure during the next impregnation cycle. The impregnated composites are then given a final heat treatment in the range 2500 to 3000 C to fully graphitize the fibers and the matrix carbon. The composites are then infiltrated with pyrolytic carbon by chemical vapor deposition in the range 1000 to 1300 C at a reduced pressure for approximately one hundred and fifty (150) hours.

  14. Substantial global carbon uptake by cement carbonation

    NASA Astrophysics Data System (ADS)

    Xi, Fengming; Davis, Steven J.; Ciais, Philippe; Crawford-Brown, Douglas; Guan, Dabo; Pade, Claus; Shi, Tiemao; Syddall, Mark; Lv, Jie; Ji, Lanzhu; Bing, Longfei; Wang, Jiaoyue; Wei, Wei; Yang, Keun-Hyeok; Lagerblad, Björn; Galan, Isabel; Andrade, Carmen; Zhang, Ying; Liu, Zhu

    2016-12-01

    Calcination of carbonate rocks during the manufacture of cement produced 5% of global CO2 emissions from all industrial process and fossil-fuel combustion in 2013. Considerable attention has been paid to quantifying these industrial process emissions from cement production, but the natural reversal of the process--carbonation--has received little attention in carbon cycle studies. Here, we use new and existing data on cement materials during cement service life, demolition, and secondary use of concrete waste to estimate regional and global CO2 uptake between 1930 and 2013 using an analytical model describing carbonation chemistry. We find that carbonation of cement materials over their life cycle represents a large and growing net sink of CO2, increasing from 0.10 GtC yr-1 in 1998 to 0.25 GtC yr-1 in 2013. In total, we estimate that a cumulative amount of 4.5 GtC has been sequestered in carbonating cement materials from 1930 to 2013, offsetting 43% of the CO2 emissions from production of cement over the same period, not including emissions associated with fossil use during cement production. We conclude that carbonation of cement products represents a substantial carbon sink that is not currently considered in emissions inventories.

  15. Method of making carbon-carbon composites

    DOEpatents

    Engle, Glen B.

    1991-01-01

    A process for making a carbon-carbon composite having a combination of high crystallinity, high strength, high modulus and high thermal and electrical conductivity. High-modulus/high-strength mesophase derived carbon fibers are woven into a suitable cloth. Layers of this easily graphitizable woven cloth are covered with petroleum or coal tar pitch and pressed at a temperature a few degrees above the softening point of the pitch to form a green laminated composite. The green composite is restrained in a suitable fixture and heated slowly to carbonize the pitch binder. The carbonized composite is then impregnated several times with pitch by covering the composite with hot pitch under pressure. The composites are given a heat treatment between each impregnation step to crack up the infiltrated carbon and allow additional pitch to enter the microstructure during the next impregnation cycle. The impregnated composites are then given a final heat treatment in the range 2500.degree. to 3000.degree. C. to fully graphitize the fibers and the matrix carbon. The composites are then infiltrated with pyrolytic carbon by chemical vapor deposition in the range 1000.degree. to 1300.degree. C. at a reduced pressure for approximately one hundred and fifty (150) hours.

  16. [Carbonic anhydrase of blue-green alga Spirulina platensis].

    PubMed

    Komarova, Iu M; Terekhova, I V; Doman, N G; Al'bitskaia, O N

    1976-01-01

    Carboanhydrase (carbonate-hydroliase EC 4.2.1.1.) is found in the extract of Spirulina platensis cells. A linear dependency of the enzyme activity on the protein concentration; pH optimum is found to be 8.0. Specific activity of carboanhydrase is 3 muM/min-mg of protein under the concentration of CO2 of 4-10(-3) M, appearing Michelis constant being 4.9-10(-3) M. The enzyme was stabilized with 10 mM of cisteine, its activity was inhibited by 50% with sulphanylamide (1-10(-5) M), acetazolamide (8--10(-7) M) and Cl- ions (5-10(-2) M). The activity of carboanhydrase, as well as the rate of NaH14CO3 fixation, depended on the pH value of cultural medium.

  17. Recent advances in carbon-carbon materials systems

    SciTech Connect

    Rummler, D.R.

    1982-11-01

    Carbon-carbon materials and new oxidation resistant coating developments are discussed. Potential areas of application are highlighted. A short bibliography of selected references is included that describe carbon-carbon materials and related technology in detail.

  18. Carbon Monoxide (CO)

    MedlinePlus

    ... United States Environmental Protection Agency Search Search Indoor Air Quality (IAQ) Share Facebook Twitter Google+ Pinterest Contact Us Carbon Monoxide's Impact on Indoor Air Quality On this page: Overview Sources of Carbon Monoxide ...

  19. Carbon Based Nanotechnology: Review

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Saini, Subhash (Technical Monitor)

    1999-01-01

    This presentation reviews publicly available information related to carbon based nanotechnology. Topics covered include nanomechanics, carbon based electronics, nanodevice/materials applications, nanotube motors, nano-lithography and H2O storage in nanotubes.

  20. Sodium carbonate poisoning

    MedlinePlus

    Sodium carbonate (known as washing soda or soda ash) is a chemical found in many household and ... products. This article focuses on poisoning due to sodium carbonate. This article is for information only. Do ...

  1. Carbon nanotube nanoelectrode arrays

    DOEpatents

    Ren, Zhifeng; Lin, Yuehe; Yantasee, Wassana; Liu, Guodong; Lu, Fang; Tu, Yi

    2008-11-18

    The present invention relates to microelectode arrays (MEAs), and more particularly to carbon nanotube nanoelectrode arrays (CNT-NEAs) for chemical and biological sensing, and methods of use. A nanoelectrode array includes a carbon nanotube material comprising an array of substantially linear carbon nanotubes each having a proximal end and a distal end, the proximal end of the carbon nanotubes are attached to a catalyst substrate material so as to form the array with a pre-determined site density, wherein the carbon nanotubes are aligned with respect to one another within the array; an electrically insulating layer on the surface of the carbon nanotube material, whereby the distal end of the carbon nanotubes extend beyond the electrically insulating layer; a second adhesive electrically insulating layer on the surface of the electrically insulating layer, whereby the distal end of the carbon nanotubes extend beyond the second adhesive electrically insulating layer; and a metal wire attached to the catalyst substrate material.

  2. Interstellar carbon in meteorites

    NASA Technical Reports Server (NTRS)

    Swart, P. K.; Grady, M. M.; Pillinger, C. T.; Lewis, R. S.; Anders, E.

    1983-01-01

    The Murchison and Allende chondrites contain up to 5 parts per million carbon that is enriched in carbon-13 by up to +1100 per mil (the ratio of carbon-12 to carbon-13 is approximately 42, compared to 88 to 93 for terrestrial carbon). This 'heavy' carbon is associated with neon-22 and with anomalous krypton and xenon showing the signature of the s-process (neutron capture on a slow time scale). It apparently represents interstellar grains ejected from late-type stars. A second anomalous xenon component ('CCFXe') is associated with a distinctive, light carbon (depleted in carbon-13 by 38 per mil), which, however, falls within the terrestrial range and hence may be of either local or exotic origin.

  3. Synthetic carbon precursor materials

    SciTech Connect

    Frame, B.J.

    1986-03-01

    Synthetic carbon precursor systems offer advantages over natural petroleum and coal-tar pitch precursors in that they can reproducibly provide a material with a known and uniform composition. They also permit controlled modifications of the derived carbon's properties through variations in the precursor's properties and processing conditions. Extensive research efforts at Oak Ridge have been directed toward the production and characterization of synthetic carbon precursors and the correlations that exist between carbon precursor properties and the properties of the ultimate carbon. This report describes how synthetic carbon precursors can be used to tailor and develop reproducible carbon structures for advanced materials applications. The potential and capability for performing carbon material development at Oak Ridge is also described.

  4. Trading forest carbon - OSU

    EPA Science Inventory

    Issues associate with trading carbon sequestered in forests are discussed. Scientific uncertainties associated with carbon measurement are discussed with respect to proposed accounting procedures. Major issues include: (1) Establishing baselines. (2) Determining additivity from f...

  5. Not just carbon widgets

    NASA Astrophysics Data System (ADS)

    2016-08-01

    Forests are important for the global carbon cycle, and for mitigating greenhouse gas emissions. However, the role forests play in carbon sequestration should not eclipse everything else we value them for.

  6. When carbon footprints hop

    NASA Astrophysics Data System (ADS)

    Petherick, Anna

    2012-07-01

    Despite having achieved legally binding commitments on emissions reductions, many countries have increased their appetite for carbon-intensive products, making up the difference through international trade. Anna Petherick reports on the sticky task of regulating these invisible carbon flows.

  7. Metal filled porous carbon

    DOEpatents

    Gross, Adam F.; Vajo, John J.; Cumberland, Robert W.; Liu, Ping; Salguero, Tina T.

    2011-03-22

    A porous carbon scaffold with a surface and pores, the porous carbon scaffold containing a primary metal and a secondary metal, where the primary metal is a metal that does not wet the surface of the pores of the carbon scaffold but wets the surface of the secondary metal, and the secondary metal is interspersed between the surface of the pores of the carbon scaffold and the primary metal.

  8. Carbon Goes To…

    ERIC Educational Resources Information Center

    Savasci, Funda

    2014-01-01

    The purposes of this activity are to help middle school students understand the carbon cycle and realize how human activities affect the carbon cycle. This activity consists of two parts. The first part of the activity focuses on the carbon cycle, especially before the Industrial Revolution, while the second part of the activity focuses on how…

  9. Protolytic carbon film technology

    SciTech Connect

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  10. Intro to Carbon Sequestration

    ScienceCinema

    None

    2016-07-12

    NETL's Carbon Sequestration Program is helping to develop technologies to capture, purify, and store carbon dioxide (CO2) in order to reduce greenhouse gas emissions without adversely influencing energy use or hindering economic growth. Carbon sequestration technologies capture and store CO2 that would otherwise reside in the atmosphere for long periods of time.

  11. Intro to Carbon Sequestration

    SciTech Connect

    2008-03-06

    NETL's Carbon Sequestration Program is helping to develop technologies to capture, purify, and store carbon dioxide (CO2) in order to reduce greenhouse gas emissions without adversely influencing energy use or hindering economic growth. Carbon sequestration technologies capture and store CO2 that would otherwise reside in the atmosphere for long periods of time.

  12. Carbon/Carbon Pistons for Internal Combustion Engines

    NASA Technical Reports Server (NTRS)

    Taylor, A. H.

    1986-01-01

    Carbon/carbon piston performs same function as aluminum pistons in reciprocating internal combustion engines while reducing weight and increasing mechanical and thermal efficiencies of engine. Carbon/carbon piston concept features low piston-to-cylinder wall clearance - so low piston rings and skirts unnecessary. Advantages possible by negligible coefficient of thermal expansion of carbon/carbon.

  13. Conversion of carbon-containing materials to carbon monoxide

    SciTech Connect

    Davis, G. D.; Hill, J. C.; Mcminn, T. D.; Rooks, C. W.

    1981-06-09

    Carbon-containing materials are gasified to produce high purity carbon monoxide in a three zone unified system (Oxidizer, reducer and gasifier) using a metal oxide as the oxygen and heat source for the gasification with carbon monoxide. Carbon monoxide contacts the metal oxide prior to the gasification to release the oxygen and convert the carbon monoxide to carbon dioxide as the gasification medium.

  14. Ternary Phosphide Ho 2Cu 6- xP 5- y, Its Crystal Structure, and REm+ n(Cu 2P 3) m(Cu 4P 2) n Relationship with Other Rhombohedral Rare-Earth Copper Phosphides

    NASA Astrophysics Data System (ADS)

    Mozharivskyj, Yurij; Kuz'ma, Yurij B.

    2000-04-01

    Crystals of the phosphide Ho2Cu6-xP5-y (x=0.41, y=0.50) have been prepared by annealing pressed powders of the elements at 800°C for 2 weeks. The structure was determined by single-crystal methods: space group Roverline3m (No. 166), Z=3, a=3.976(1) Å, c=40.554(8) Å, R=0.045 for 243 independent reflections [F>4σ(F)]. The unit cell of Ho2Cu6-xP5-y can be built from a close packing of Ho atoms and fragments of Cu3P, with one of the fragments containing additional P atoms. It can be also considered as an intercalation of additional P atoms in the YbCu3-xP2 structure (P. Klüfers, A. Mewis, and H. U. Schuster, Z. Kristallogr. 149, 211 (1979)). The REm+n(Cu2P3)m(Cu4P2)n relationship with other rare-earth copper phosphides, having similar structural characteristics is discussed.

  15. GATA3 mRNA expression, but not mutation, associates with longer progression-free survival in ER-positive breast cancer patients treated with first-line tamoxifen for recurrent disease.

    PubMed

    Liu, Jingjing; Prager-van der Smissen, Wendy J C; Look, Maxime P; Sieuwerts, Anieta M; Smid, Marcel; Meijer-van Gelder, Marion E; Foekens, John A; Hollestelle, Antoinette; Martens, John W M

    2016-06-28

    In breast cancer, GATA3 mutations have been associated with a favorable prognosis and the response to neoadjuvant aromatase inhibitor treatment. Therefore, we investigated whether GATA3 mutations predict the outcome of tamoxifen treatment in the advanced setting. In a retrospective study consisting of 235 hormone-naive patients with ER-positive breast cancer who received tamoxifen as first-line treatment for recurrent disease, GATA3 mutations (in 14.0% of patients) did not significantly associate with either the overall response rate (ORR) or with the length of progression-free survival (PFS) after the start of tamoxifen therapy. Interestingly, among 148 patients for whom both mutation and mRNA expression data were available, GATA3 mutations associated with an increased expression of GATA3. However, only 23.7% of GATA3 high tumors had a mutation. Evaluation of the clinical significance of GATA3 mRNA revealed that it was associated with prolonged PFS, but not with the ORR, also in multivariate analysis. Thus, GATA3 mRNA expression, but not GATA3 mutation, is an independent predictor of prolonged PFS in ER-positive breast cancer patients who received first-line tamoxifen for recurrent disease. Besides GATA3 mutation, other mechanisms must exist that underlie increased GATA3 levels.

  16. Long-term oral administration of glucosamine or chondroitin sulfate reduces destruction of cartilage and up-regulation of MMP-3 mRNA in a model of spontaneous osteoarthritis in Hartley guinea pigs.

    PubMed

    Taniguchi, Shin; Ryu, Junnosuke; Seki, Masayuki; Sumino, Takanobu; Tokuhashi, Yasuaki; Esumi, Mariko

    2012-05-01

    Histological and molecular changes were examined to investigate the effects of long-term administration of glucosamine (GlcN) and chondroitin sulfate (CS) in a model of spontaneous osteoarthritis (OA) in Hartley guinea pigs. Three groups of female 3-week-old Hartley guinea pigs received GlcN, CS, and neither agent, respectively. Five animals in each group were sacrificed at 8, 12, and 18 months of age. At 8 months of age, Hartley guinea pigs had severe degeneration of knee joint cartilage, chondrocyte apoptosis, marked reduction of tissue total RNA, decreases of aggrecan and collagen type 2 mRNAs, and increases in MMP-3 and MMP-8 mRNAs. Long-term administration of GlcN and CS reduced cartilage degeneration at 8 months of age. The marked loss of total RNA and the increase in MMP-3 mRNA were also inhibited by GlcN and CS. Thus, long-term oral administration of GlcN or CS inhibits OA progression, maintains total RNA and down-regulates MMP-3 mRNA in a spontaneous OA model in Hartley guinea pigs.

  17. Ternary rare-earth ruthenium and iridium germanides RE{sub 3}M{sub 2}Ge{sub 3} (RE=Y, Gd–Tm, Lu; M=Ru, Ir)

    SciTech Connect

    Oliynyk, Anton O.; Stoyko, Stanislav S.; Mar, Arthur

    2013-06-15

    Through arc-melting reactions of the elements and annealing at 800 °C, the ternary rare-earth germanides RE{sub 3}Ru{sub 2}Ge{sub 3} and RE{sub 3}Ir{sub 2}Ge{sub 3} have been prepared for most of the smaller RE components (RE=Y, Gd–Tm, Lu). In the iridium-containing reactions, the new phases RE{sub 2}IrGe{sub 2} were also generally formed as by-products. Powder X-ray diffraction revealed orthorhombic Hf{sub 3}Ni{sub 2}Si{sub 3}-type structures (space group Cmcm, Z=4) for RE{sub 3}M{sub 2}Ge{sub 3} (M=Ru, Ir) and monoclinic Sc{sub 2}CoSi{sub 2}-type structures (space group C2/m, Z=4) for RE{sub 2}IrGe{sub 2}. Full crystal structures were determined by single-crystal X-ray diffraction for all members of RE{sub 3}Ru{sub 2}Ge{sub 3} (a=4.2477(6) Å, b=10.7672(16) Å, c=13.894(2) Å for RE=Y; a=4.2610(3)–4.2045(8) Å, b=10.9103(8)–10.561(2) Å, c=14.0263(10)–13.639(3) Å in the progression of RE from Gd to Lu) and for Tb{sub 3}Ir{sub 2}Ge{sub 3} (a=4.2937(3) Å, b=10.4868(7) Å, c=14.2373(10) Å). Both structures can be described in terms of CrB- and ThCr{sub 2}Si{sub 2}-type slabs built from Ge-centred trigonal prisms. However, band structure calculations on Y{sub 3}Ru{sub 2}Ge{sub 3} support an alternative description for RE{sub 3}M{sub 2}Ge{sub 3} based on [M{sub 2}Ge{sub 3}] layers built from linked MGe{sub 4} tetrahedra, which emphasizes the strong M–Ge covalent bonds present. The temperature dependence of the electrical resistivity of RE{sub 3}Ru{sub 2}Ge{sub 3} generally indicates metallic behaviour but with low-temperature transitions visible for some members (RE=Gd, Tb, Dy) that are probably associated with magnetic ordering of the RE atoms. Anomalously, Y{sub 3}Ru{sub 2}Ge{sub 3} exhibits semiconductor-like behaviour of uncertain origin. Magnetic measurements on Dy{sub 3}Ru{sub 2}Ge{sub 3} reveal antiferromagnetic ordering at 3 K and several unusual field-dependent transitions suggestive of complex spin reorientation processes. - Graphical abstract

  18. Water for Carbon, Carbon for Water

    NASA Astrophysics Data System (ADS)

    Carminati, Andrea; Kroener, Eva; Ahmed, Mutez A. A.; Zarebanadkouki, Mohsen; Holz, Maire; Ghezzehei, Teamrat

    2015-04-01

    Plant roots exude approximately 10% of the carbon assimilated through photosynthesis into the soil, a process referred to as rhizodeposition. Although this may look like a waste of energy, it has been shown that the carbon exuded into the soil helps roots to take up nutrients and promote positive interactions with microorganisms. Here, we show that the mucilaginous fraction of the rhizodeposits, referred to as mucilage, plays also a crucial role on soil-plant water relations and triggers positive feedbacks between the water and carbon cycles. Mucilage is a gel that can absorb large volumes of water, altering the physical properties of the rhizosphere and maintaining the rhizosphere wet and conductive when the soil dries. Acting as a hydraulic bridge between roots and the soil, mucilage facilitates root water uptake and maintains transpiration and photosynthesis in dry soils. By employing a simplified model of root water uptake coupled with mucilage dynamics, we found that indeed the carbon exuded in form of mucilage maintains photosynthesis in dry soils resulting a in a net gain of carbon. In summary, by exuding mucilage, plants modify the physical soil environment, have a better access to water when water is scarce, and maintain photosynthesis for a prolonged time during drought. We propose that mucilage exudation is a plant trait conferring drought resistance. In other words: water for carbon, but also carbon for water.

  19. Method of making carbon-carbon composites

    SciTech Connect

    Engle, G.B.

    1993-06-08

    A method for fabricating a high-strength, high-modulus and high thermal and electrical conducting 2D laminate carbon-carbon composite is described comprising the steps of: (a) forming a green laminate composite comprising: (1) graphitizible carbon cloth plies, (2) fine graphitizible pitch powder; said cloth plies comprising mesophase derived pitch fiber tow with moduli in a range of 25 to 140 Msi, and (3) thermal conductivity enhancers; (b) heating the green laminate composite to a temperature high enough to cause the pitch powder to soften and pressing the composite to form a pressed green laminate composite comprised of graphitizible carbon cloth, pitch matrix and thermal conductivity enhancers; (c) heating the pressed green composite to at least 500 C. to: (1) carbonize the pitch, (2) form a carbon matrix and (3) shrink and crack the matrix carbon; (d) impregnating the composite with additional graphitizible pitch by covering the composite with the pitch and heating the covered composite to at least 200 C. to melt the pitch and permit it to flow into the composite and then increasing the pressure to at least 15 Psi; (e) heating the composites to at least 900 C.; (f) repeating steps d and e at least once; (g) heating the composite to between 2,400 to 3,100 C to graphitize the fibers and the pitch matrix carbon in the composites to produce a graphitized composite having cracks and pores; and (h) reimpregnating the graphitized composites by infiltrating the cracks and pores of the composites with a hydrocarbon gas at a temperature in the range 982 to 1,490 C. and depositing pyrolytic carbon in the pores and cracks.

  20. Instrumental carbon monoxide dosimetry.

    PubMed

    Stetter, J R; Rutt, D R

    1980-10-01

    Modern technology for the ambient monitoring of carbon monoxide has been developed to produce a portable electrochemical instrument capable of the personal exposure to carbon monoxide. The performance characteristics of this device have been studied so that the unambiguous interpretation of field data could be performed. A study of the carbon monoxide exposure in a light manufacturing facility illustrate that effective dosimetry can be performed with expectations of accuracy typically better than +/- 15%, and that voluntary carbon monoxide exposures such as smoking were a significant contribution to the individual's exposure. Significant definition of the carbon monoxide exposure profile can be achieved with an instrument approach to the collection of the dosimetric data.

  1. Manufacture of finely divided carbon

    SciTech Connect

    Walker, D.G.

    1980-01-22

    Finely divided carbon is manufactured by a process producing a gaseous stream containing carbon monoxide by reacting coal and air in a slagging ash gasifier, separating carbon monoxide from the gaseous mixture, and disproportionating the carbon monoxide to produce finely divided carbon and carbon dioxide, the latter of which is recycled to the gasifier.

  2. The Carbon Cycle

    NASA Astrophysics Data System (ADS)

    Wigley, T. M. L.; Schimel, D. S.

    2005-08-01

    Reducing carbon dioxide (CO2) emissions is imperative to stabilizing our future climate. Our ability to reduce these emissions combined with an understanding of how much fossil-fuel-derived CO2 the oceans and plants can absorb is central to mitigating climate change. In The Carbon Cycle, leading scientists examine how atmospheric carbon dioxide concentrations have changed in the past and how this may affect the concentrations in the future. They look at the carbon budget and the "missing sink" for carbon dioxide. They offer approaches to modeling the carbon cycle, providing mathematical tools for predicting future levels of carbon dioxide. This comprehensive text incorporates findings from the recent IPCC reports. New insights, and a convergence of ideas and views across several disciplines make this book an important contribution to the global change literature.

  3. Carbon stocks of intact mangroves and carbon emissions arising from their conversion in the Dominican Republic.

    PubMed

    Kauffman, J Boone; Heider, Chris; Norfolk, Jennifer; Payton, Frederick

    2014-04-01

    Mangroves are recognized to possess a variety of ecosystem services including high rates of carbon sequestration and storage. Deforestation and conversion of these ecosystems continue to be high and have been predicted to result in significant carbon emissions to the atmosphere. Yet few studies have quantified the carbon stocks or losses associated with conversion of these ecosystems. In this study we quantified the ecosystem carbon stocks of three common mangrove types of the Caribbean as well as those of abandoned shrimp ponds in areas formerly occupied by mangrove-a common land-use conversion of mangroves throughout the world. In the mangroves of the Montecristi Province in Northwest Dominican Republic we found C stocks ranged from 706 to 1131 Mg/ha. The medium-statured mangroves (3-10 m in height) had the highest C stocks while the tall (> 10 m) mangroves had the lowest ecosystem carbon storage. Carbon stocks of the low mangrove (shrub) type (< 3 m) were relatively high due to the presence of carbon-rich soils as deep as 2 m. Carbon stocks of abandoned shrimp ponds were 95 Mg/ha or approximately 11% that of the mangroves. Using a stock-change approach, the potential emissions from the conversion of mangroves to shrimp ponds ranged from 2244 to 3799 Mg CO2e/ha (CO2 equivalents). This is among the largest measured C emissions from land use in the tropics. The 6260 ha of mangroves and converted mangroves in the Montecristi Province are estimated to contain 3,841,490 Mg of C. Mangroves represented 76% of this area but currently store 97% of the carbon in this coastal wetland (3,696,722 Mg C). Converted lands store only 4% of the total ecosystem C (144,778 Mg C) while they comprised 24% of the area. By these metrics the replacement of mangroves with shrimp and salt ponds has resulted in estimated emissions from this region totaling 3.8 million Mg CO2e or approximately 21% of the total C prior to conversion. Given the high C stocks of mangroves, the high emissions

  4. Process of making carbon-carbon composites

    NASA Technical Reports Server (NTRS)

    Withers, James C. (Inventor); Loutfy, Raouf O. (Inventor); Kowbel, Witold (Inventor); Bruce, Calvin (Inventor); Vaidyanathan, Ranji (Inventor)

    2000-01-01

    A carbon composite structure, for example, an automotive engine piston, is made by preparing a matrix including of a mixture of non crystalline carbon particulate soluble in an organic solvent and a binder that has a liquid phase. The non crystalline particulate also contains residual carbon hydrogen bonding. An uncured structure is formed by combining the matrix mixture, for example, carbon fibers such as graphite dispersed in the mixture and/or graphite cloth imbedded in the mixture. The uncured structure is cured by pyrolyzing it in an inert atmosphere such as argon. Advantageously, the graphite reinforcement material is whiskered prior to combining it with the matrix mixture by a novel method involving passing a gaseous metal suboxide over the graphite surface.

  5. Fracture Toughness of Carbon/Carbon Composites.

    DTIC Science & Technology

    1991-07-27

    during which tensile stresses develop in the matrix as a result of the thermal expansion coefficient differential between the matrix and yarns. In...thermal expansion differential . Figure 3.4 depicts the sample surface along the R-C plane. The circumferential yarns are horizontal and the radial yarns...Milieko), Elsevier, Amsterdam, (1981), pp. 109-175. 5 126 3 U 127 16). C.T. Robinson, "Damage Mechanisums and Failure of 3-D Carbon-Carbon Composites," SRI

  6. Mechanical behavior of carbon-carbon composites

    NASA Technical Reports Server (NTRS)

    Rozak, G. A.

    1984-01-01

    A general background, test plan, and some results of preliminary examinations of a carbon-carbon composite material are presented with emphasis on mechanical testing and inspection techniques. Experience with testing and evaluation was gained through tests of a low modulus carbon-carbon material, K-Karb C. The properties examined are the density - 1.55 g/cc; four point flexure strength in the warp - 137 MPa (19,800 psi) and the fill - 95.1 MPa (13,800 psi,) directions; and the warp interlaminar shear strength - 14.5 MPa (2100 psi). Radiographic evaluation revealed thickness variations and the thinner areas of the composite were scrapped. The ultrasonic C-scan showed attenuation variations, but these did not correspond to any of the physical and mechanical properties measured. Based on these initial tests and a survey of the literature, a plan has been devised to examine the effect of stress on the oxidation behavior, and the strength degradation of coated carbon-carbon composites. This plan will focus on static fatigue tests in the four point flexure mode in an elevated temperature, oxidizing environment.

  7. Carbon isotopes in mollusk shell carbonates

    NASA Astrophysics Data System (ADS)

    McConnaughey, Ted A.; Gillikin, David Paul

    2008-10-01

    Mollusk shells contain many isotopic clues about calcification physiology and environmental conditions at the time of shell formation. In this review, we use both published and unpublished data to discuss carbon isotopes in both bivalve and gastropod shell carbonates. Land snails construct their shells mainly from respired CO2, and shell δ13C reflects the local mix of C3 and C4 plants consumed. Shell δ13C is typically >10‰ heavier than diet, probably because respiratory gas exchange discards CO2, and retains the isotopically heavier HCO3 -. Respired CO2 contributes less to the shells of aquatic mollusks, because CO2/O2 ratios are usually higher in water than in air, leading to more replacement of respired CO2 by environmental CO2. Fluid exchange with the environment also brings additional dissolved inorganic carbon (DIC) into the calcification site. Shell δ13C is typically a few ‰ lower than ambient DIC, and often decreases with age. Shell δ13C retains clues about processes such as ecosystem metabolism and estuarine mixing. Ca2+ ATPase-based models of calcification physiology developed for corals and algae likely apply to mollusks, too, but lower pH and carbonic anhydrase at the calcification site probably suppress kinetic isotope effects. Carbon isotopes in biogenic carbonates are clearly complex, but cautious interpretation can provide a wealth of information, especially after vital effects are better understood.

  8. A 3-mW/Gbps 1.8-V Operated Current-Reuse Low-Voltage Differential Signaling Driver Using Vertical Metal-Oxide-Semiconductor Field-Effect Transistors

    NASA Astrophysics Data System (ADS)

    Tanoi, Satoru; Endoh, Tetsuo

    2013-04-01

    A low-voltage differential signaling (LVDS) driver with a new current reuse topology is proposed for low power-supply voltage (VDD) operation. The proposed driver has a new current mirror with shared MOSFET and is designed using vertical MOSFETs. The new current mirror reduces the output degradation to less than half of the conventional. And the design with vertical MOSFETs reduces the voltage drop of the eight-stage cascode circuit to 77.6% of that with planar ones. Our current reuse driver achieves 3-mW/Gbps with 2.5-Gbps and 1.8-V VDD operation in the simulation using 0.18-µm gate length MOSFET parameters. The achieved reduction of the power normalized by the output power at 1.8-V VDD is larger than 30% of that for the conventional drivers.

  9. RNA editing makes mistakes in plant mitochondria: editing loses sense in transcripts of a rps19 pseudogene and in creating stop codons in coxI and rps3 mRNAs of Oenothera.

    PubMed Central

    Schuster, W; Brennicke, A

    1991-01-01

    An intact gene for the ribosomal protein S19 (rps19) is absent from Oenothera mitochondria. The conserved rps19 reading frame found in the mitochondrial genome is interrupted by a termination codon. This rps19 pseudogene is cotranscribed with the downstream rps3 gene and is edited on both sides of the translational stop. Editing, however, changes the amino acid sequence at positions that were well conserved before editing. Other strange editings create translational stops in open reading frames coding for functional proteins. In coxI and rps3 mRNAs CGA codons are edited to UGA stop codons only five and three codons, respectively, downstream to the initiation codon. These aberrant editings in essential open reading frames and in the rps19 pseudogene appear to have been shifted to these positions from other editing sites. These observations suggest a requirement for a continuous evolutionary constraint on the editing specificities in plant mitochondria. Images PMID:1762921

  10. Activated carbon from biomass

    NASA Astrophysics Data System (ADS)

    Manocha, S.; Manocha, L. M.; Joshi, Parth; Patel, Bhavesh; Dangi, Gaurav; Verma, Narendra

    2013-06-01

    Activated carbon are unique and versatile adsorbents having extended surface area, micro porous structure, universal adsorption effect, high adsorption capacity and high degree of surface reactivity. Activated carbons are synthesized from variety of materials. Most commonly used on a commercial scale are cellulosic based precursors such as peat, coal, lignite wood and coconut shell. Variation occurs in precursors in terms of structure and carbon content. Coir having very low bulk density and porous structure is found to be one of the valuable raw materials for the production of highly porous activated carbon and other important factor is its high carbon content. Exploration of good low cost and non conventional adsorbent may contribute to the sustainability of the environment and offer promising benefits for the commercial purpose in future. Carbonization of biomass was carried out in a horizontal muffle furnace. Both carbonization and activation were performed in inert nitrogen atmosphere in one step to enhance the surface area and to develop interconnecting porosity. The types of biomass as well as the activation conditions determine the properties and the yield of activated carbon. Activated carbon produced from biomass is cost effective as it is easily available as a waste biomass. Activated carbon produced by combination of chemical and physical activation has higher surface area of 2442 m2/gm compared to that produced by physical activation (1365 m2/gm).

  11. Carbon dioxide sensor

    DOEpatents

    Dutta, Prabir K [Worthington, OH; Lee, Inhee [Columbus, OH; Akbar, Sheikh A [Hilliard, OH

    2011-11-15

    The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

  12. Heterotetranuclear oxalato-bridged Re(IV)3M(II) (M = Mn, Fe, Co, Ni, Cu) complexes: a new example of a single-molecule magnet (M = Ni).

    PubMed

    Martínez-Lillo, José; Armentano, Donatella; De Munno, Giovanni; Wernsdorfer, Wolfgang; Clemente-Juan, Juan Modesto; Krzystek, J; Lloret, Francesc; Julve, Miguel; Faus, Juan

    2009-04-06

    The use of the mononuclear species (NBu(4))(2)[Re(IV)Cl(4)(ox)] (NBu(4)(+) = tetra-n-butylammonium cation; ox = oxalate dianion) as a ligand toward fully solvated divalent first-row transition-metal ions affords the tetranuclear complexes (NBu(4))(4)[{Re(IV)Cl(4)(mu-ox)}(3)M(II)] with M = Mn (1), Fe (2), Co (3), Ni (4), and Cu (5). Their structure is made up of discrete [{ReCl(4)(mu-ox)}(3)M](4-) anions and bulky NBu(4)(+) cations. The complexes 2-5 crystallize in the triclinic system with space group P1; 2 and 5 as well as 3 and 4 are isostructural. The Re and M atoms exhibit somewhat distorted ReCl(4)O(2) and MO(6) octahedral surroundings, with the oxalate groups adopting the bis-bidentate bridging mode. Magnetic susceptibility measurements on polycrystalline samples of 1-5 in the temperature range 1.9-300 K show the occurrence of intramolecular antiferromagnetic [J = -1.30 cm(-1) (1)] and ferromagnetic couplings [J = +1.62 (2), +3.0 (3), +16.3 (4), and +4.64 cm(-1) (5)], with the Hamiltonian being defined as H = -J[S(M)(S(Re1) + S(Re2) + S(Re3))]. Compound 4 is the first example of an oxalato-bridged heterometallic species that behaves as a single-molecule magnet with a ground-state spin S = (11)/(2) and D = -0.8(1) cm(-1), as shown by the study of its static and dynamic magnetic properties and a high-frequency electron paramagnetic resonance study on polycrystalline samples together with detailed micro-SQUID measurements on single crystals.

  13. [Fe(TPT)(2/3){M(I)(CN)2}2]⋅nSolv (M(I) = Ag, Au): new bimetallic porous coordination polymers with spin-crossover properties.

    PubMed

    Arcís-Castillo, Zulema; Muñoz, M Carmen; Molnár, Gábor; Bousseksou, Azzedine; Real, José Antonio

    2013-05-17

    Two new heterobimetallic porous coordination polymers with the formula [Fe(TPT)(2/3){M(I)(CN)2}2]⋅nSolv (TPT = [(2,4,6-tris(4-pyridyl)-1,3,5-triazine]; M(I) = Ag (nSolv = 0, 1 MeOH, 2 CH2Cl2), Au (nSolv = 0, 2CH2Cl2)) have been synthesized and their crystal structures were determined at 120 K and 293 K by single-crystal X-ray analysis. These structures crystallized in the trigonal R-3m space group. The Fe(II) ion resides at an inversion centre that defines a [FeN6] coordination core. Four dicyanometallate groups coordinate at the equatorial positions, whilst the axial positions are occupied by the TPT ligand. Each TPT ligand is centred in a ternary axis and bridges three crystallographically equivalent Fe(II) ions, whilst each dicyanometallate group bridges two crystallographically equivalent Fe(II) ions that define a 3D network with the topology of NbO. There are two such networks, which interpenetrate each other, thereby giving rise to large spaces in which very labile solvent molecules are included (CH2Cl2 or MeOH). Crystallographic analysis confirmed the reversible structural changes that were associated with the occurrence of spin-crossover behaviour at the Fe(II) ions, the most significant structural variation being the change in unit-cell volume (about 59 Å(3) per Fe(II) ion). The spin-crossover behaviour has been monitored by means of thermal dependence of the magnetic properties, Mössbauer spectroscopy, and calorimetry.

  14. Spatially Explicit Full Carbon and Greenhouse Gas Accounting for the Midwestern and Continental US: Modeling and Decision Support for Carbon Management

    NASA Astrophysics Data System (ADS)

    West, T. O.; Brandt, C. C.; Wilson, B. S.; Hellwinckel, C. M.; Mueller, M.; Tyler, D. D.; de La Torre Ugarte, D. G.; Larson, J. A.; Nelson, R. G.; Marland, G.

    2006-12-01

    Full carbon accounting for terrestrial ecosystems is intended to quantify changes in net carbon emissions caused by changes in land management. On agricultural lands, changes in land management can cause changes in CO2 emissions from fossil fuel use, agricultural lime, and decomposition of soil carbon. Changes in off-site emissions can occur from the manufacturing of fertilizers, pesticides, and agricultural lime. We are developing a full carbon accounting framework that can be used for estimates of on-site net carbon flux or for full greenhouse gas accounting at a high spatial resolution. Estimates are based on the assimilation of national inventory data, soil carbon dynamics based on empirical analyses of field data, and Landsat-derived remote sensing products with 30x30m resolution. We applied this framework to a mid-western region of the US that consists of 679 counties approximately centered around Iowa. We estimate the 1990 baseline soil carbon for this region to be 4,099 Tg C to a 3m maximum depth. Soil carbon accumulation of 57.3 Tg C is estimated to have occurred in this region between 1991-2000. Without accounting for soil carbon loss associated with changes to more intense tillage practices, our estimate increases to 66.3 Tg C. This indicates that on-site permanence of soil carbon is approximately 86% with no additional economic incentives provided for soil carbon sequestration practices. Total net carbon flux from the agricultural activities in the Midwestern US in 2000 is estimated at about -5 Tg C. This estimate includes carbon uptake, decomposition, harvested products, and on-site fossil fuel emissions. Therefore, soil carbon accumulation offset on-site emissions in 2000. Our carbon accounting framework offers a method to integrate new inventory and remote sensing data on an annual basis, account for alternating annual trends in land management without the need for model equilibration, and provide a transparent means to monitor changes soil carbon

  15. Mesoporous carbon materials

    SciTech Connect

    Dai, Sheng; Wang, Xiqing

    2013-08-20

    The invention is directed to a method for fabricating a mesoporous carbon material, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic compound or material, (iii) a crosslinkable aldehyde component, and (iv) at least 0.5 M concentration of a strong acid having a pKa of or less than -2, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a mesoporous carbon material. The invention is also directed to a mesoporous carbon material having an improved thermal stability, preferably produced according to the above method.

  16. Mesoporous carbon materials

    SciTech Connect

    Dai, Sheng; Wang, Xiqing

    2012-02-14

    The invention is directed to a method for fabricating a mesoporous carbon material, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic compound or material, (iii) a crosslinkable aldehyde component, and (iv) at least 0.5 M concentration of a strong acid having a pKa of or less than -2, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a mesoporous carbon material. The invention is also directed to a mesoporous carbon material having an improved thermal stability, preferably produced according to the above method.

  17. Creating With Carbon

    NASA Technical Reports Server (NTRS)

    2003-01-01

    A subsidiary of SI Diamond Technology, Inc., Applied Nanotech, of Austin, Texas, is creating a buzz among various technology firms and venture capital groups interested in the company s progressive research on carbon-related field emission devices, including carbon nanotubes, filaments of pure carbon less than one ten-thousandth the width of human hair. Since their discovery in 1991, carbon nanotubes have gained considerable attention due to their unique physical properties. For example, a single perfect carbon nanotube can range from 10 to 100 times stronger than steel, per unit weight. Recent studies also indicate that the nanotubes may be the best heat-conducting material in existence. These properties, combined with the ease of growing thin films or nanotubes by a variety of deposition techniques, make the carbon-based material one of the most desirable for cold field emission cathodes.

  18. 40 CFR 721.2084 - Carbon oxyfluoride (Carbonic difluoride).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Carbon oxyfluoride (Carbonic... Specific Chemical Substances § 721.2084 Carbon oxyfluoride (Carbonic difluoride). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance carbon oxyfluoride (CAS...

  19. 40 CFR 721.2084 - Carbon oxyfluoride (Carbonic difluoride).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Carbon oxyfluoride (Carbonic... Specific Chemical Substances § 721.2084 Carbon oxyfluoride (Carbonic difluoride). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance carbon oxyfluoride (CAS...

  20. 40 CFR 721.2084 - Carbon oxyfluoride (Carbonic difluoride).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Carbon oxyfluoride (Carbonic... Specific Chemical Substances § 721.2084 Carbon oxyfluoride (Carbonic difluoride). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance carbon oxyfluoride (CAS...

  1. 40 CFR 721.2084 - Carbon oxyfluoride (Carbonic difluoride).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Carbon oxyfluoride (Carbonic... Specific Chemical Substances § 721.2084 Carbon oxyfluoride (Carbonic difluoride). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance carbon oxyfluoride (CAS...

  2. 40 CFR 721.2084 - Carbon oxyfluoride (Carbonic difluoride).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Carbon oxyfluoride (Carbonic... Specific Chemical Substances § 721.2084 Carbon oxyfluoride (Carbonic difluoride). (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance carbon oxyfluoride (CAS...

  3. Carbon Dioxide Absorbents

    DTIC Science & Technology

    1950-05-17

    carbondioxide content of the solution was then determined. A gas mixture containing 2.6% carbon dioxide and 97.4% nitrogen was prepared in the...which carbon dioxide is removed by heat0 Since this step is usually carried out by "steam stripping ", that is, contacting the solution at its boiling...required to produce the steam required for stripping the carbon dioxide from the s olution. The method ueed in this investigation for determining the

  4. Nanostructured Carbon Coatings

    DTIC Science & Technology

    2000-01-01

    carbon coatings and explores a very broad range of potentially important carbon nanostructures that may be used in future technologies. A new method ...for the synthesis of nanostructured carbon coatings on the surface of SiC and other metal carbides is described. This method is accomplished through the...With the fall in cost of fullerene powders, this method may become important in the future as a method to produce nanocrystalline diamond free of metal

  5. Carbon Nanofiber Reinforced Polymers

    DTIC Science & Technology

    2006-01-01

    2006 2. REPORT TYPE 3. DATES COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE Carbon Nanofiber Reinforced Polymers 5a. CONTRACT NUMBER 5b...REVIEW Carbon Nanofiber Reinforced Polymers J.N. Baucom, A. Rohatgi, W.R. Pogue III, and J.P. Thomas Materials Science and Technology Division...of mass-produced and inexpensive, discontinuous carbon nanofibers to create a percolated fiber network within a polymeric matrix that will result in

  6. Carbon plasma gun

    SciTech Connect

    Mendel, C.W. Jr.; Zagar, D.M.; Mills, G.S.; Humphries, S. Jr.; Goldstein, S.A.

    1980-12-01

    A family of plasma guns supplying highly ionized carbon plasma is described. The guns are simple and inexpensive to construct and are pulsed by small capacitor banks of a few hundred joules. The output consists of 10/sup 17/--10/sup 18/ multiply ionized carbon ions traveling at about 10/sup 7/ cm/s. Neutral output is very low and arrives well after the ionized carbon. The guns and pulsers are very reliable.

  7. The carbon dioxide cycle

    USGS Publications Warehouse

    James, P.B.; Hansen, G.B.; Titus, T.N.

    2005-01-01

    The seasonal CO2 cycle on Mars refers to the exchange of carbon dioxide between dry ice in the seasonal polar caps and gaseous carbon dioxide in the atmosphere. This review focuses on breakthroughs in understanding the process involving seasonal carbon dioxide phase changes that have occurred as a result of observations by Mars Global Surveyor. ?? 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  8. Nanographene reinforced carbon/carbon composites

    NASA Astrophysics Data System (ADS)

    Bansal, Dhruv

    Carbon/Carbon Composites (CCC) are made of carbon reinforcement in carbon matrix and have high thermal stability and fatigue resistance. CCC are used in nose cones, heat shields and disc brakes of aircrafts due to their exceptional mechanical properties at high temperature. The manufacturing process of CCC involves a carbonization stage in which unwanted elements, except carbon, are eliminated from the polymer precursor. Carbonization results in the formation of voids and cracks due to the thermal mismatch between the reinforcement and the matrix and expulsion of volatiles from the polymer matrix. Thermal cracks and voids decrease the density and mechanical properties of the manufactured CCC. In this work, Nanographene Platelets (NGP) were explored as nanofillers to fill the voids/cracks and reduce thermal shrinkage in CCC. They were first compared with Vapor Grown Carbon Nanofibers (VGCNF) by dispersion of different concentrations (0.5wt%, 1.5wt%, 3wt%) in resole-type phenolic resin and were characterized to explore their effect on rheology, heat of reaction and wetting behavior. The dispersions were then cured to form nanocomposites and were characterized for morphology, flexure and thermal properties. Finally, NGP were introduced into the carbon/carboncomposites in two stages, first by spraying in different concentrations (0.5wt%, 1.5wt%, 3wt%, 5wt %) during the prepreg formation and later during densification by directly mixing in the corresponding densification mix. The manufactured NGP reinforced CCC were characterized for microstructure, porosity, bulk density and mechanical properties (Flexure and ILSS) which were further cross-checked by non-destructive techniques (vibration and ultrasonic). In this study, it was further found that at low concentration (≤ 1.5 wt%) NGP were more effective in increasing the heat of reaction and in decreasing the viscosity of the phenolic resin. The decrease in viscosity led to better wetting properties of NGP / phenolic

  9. CARBON DIOXIDE REDUCTION SYSTEM.

    DTIC Science & Technology

    CARBON DIOXIDE , *SPACE FLIGHT, RESPIRATION, REDUCTION(CHEMISTRY), RESPIRATION, AEROSPACE MEDICINE, ELECTROLYSIS, INSTRUMENTATION, ELECTROLYTES, VOLTAGE, MANNED, YTTRIUM COMPOUNDS, ZIRCONIUM COMPOUNDS, NICKEL.

  10. Carbon Materials Research

    DTIC Science & Technology

    2005-08-01

    Hurley, P.M. Liu, and T.W. Owens, "The Surface Topography of Non-Shear Treated Pitch and PAN Carbon Fibers as viewed by the STM,” J Mat. Res., 6...Effects in Pitch Wetting,” Proceedings Carbon 2003, Oviedo, Spain , July 2003 5 K. M. Chioujones, W. Ho, P. C. Chau, B. Fathollahi, P. G...Wapner, and W. P. Hoffman, “Microstructural Studies of In-Situ Mesophase Transformation in the Fabrication of Carbon-Carbon Composites,” Proceedings

  11. Reinforced Carbon Nanotubes.

    DOEpatents

    Ren, Zhifen; Wen, Jian Guo; Lao, Jing Y.; Li, Wenzhi

    2005-06-28

    The present invention relates generally to reinforced carbon nanotubes, and more particularly to reinforced carbon nanotubes having a plurality of microparticulate carbide or oxide materials formed substantially on the surface of such reinforced carbon nanotubes composite materials. In particular, the present invention provides reinforced carbon nanotubes (CNTs) having a plurality of boron carbide nanolumps formed substantially on a surface of the reinforced CNTs that provide a reinforcing effect on CNTs, enabling their use as effective reinforcing fillers for matrix materials to give high-strength composites. The present invention also provides methods for producing such carbide reinforced CNTs.

  12. Environmental carbon dioxide control

    NASA Technical Reports Server (NTRS)

    Onischak, M.; Baker, B.; Gidaspow, D.

    1974-01-01

    A study of environmental carbon dioxide control for NASA EVA missions found solid potassium carbonate to be an effective regenerable absorbent in maintaining low carbon dioxide levels. The supported sorbent was capable of repeated regeneration below 150 C without appreciable degradation. Optimum structures in the form of thin pliable sheets of carbonate, inert support and binder were developed. Interpretation of a new solid-gas pore closing model helped predict the optimum sorbent and analysis of individual sorbent sheet performance in a thin rectangular channel sorber can predict packed bed performance.

  13. Activated carbon material

    DOEpatents

    Evans, A. Gary

    1978-01-01

    Activated carbon particles for use as iodine trapping material are impregnated with a mixture of selected iodine and potassium compounds to improve the iodine retention properties of the carbon. The I/K ratio is maintained at less than about 1 and the pH is maintained at above about 8.0. The iodine retention of activated carbon previously treated with or coimpregnated with triethylenediamine can also be improved by this technique. Suitable flame retardants can be added to raise the ignition temperature of the carbon to acceptable standards.

  14. Carbon dioxide sequestration by mineral carbonation

    SciTech Connect

    Gerdemann, Stephen J.; Dahlin David C.; O'Connor William K.; Penner Larry R.

    2003-11-01

    Concerns about global warming caused by the increasing concentration of carbon dioxide and other greenhouse gases in the earth’s atmosphere have resulted in the need for research to reduce or eliminate emissions of these gases. Carbonation of magnesium and calcium silicate minerals is one possible method to achieve this reduction. It is possible to carry out these reactions either in situ (storage underground and subsequent reaction with the host rock to trap CO2 as carbonate minerals) or ex situ (above ground in a more traditional chemical processing plant). Research at the Department of Energy’s Albany Research Center has explored both of these routes. This paper will explore parameters that affect the direct carbonation of magnesium silicate minerals serpentine (Mg3Si2O5(OH)4) and olivine (Mg2SiO4) to produce magnesite (MgCO3), as well as the calcium silicate mineral, wollastonite (CaSiO3), to form calcite (CaCO3). The Columbia River Basalt Group is a multi-layered basaltic lava plateau that has favorable mineralogy and structure for storage of CO2. Up to 25% combined concentration of Ca, Fe2+, and Mg cations could react to form carbonates and thus sequester large quantities of CO2. Core samples from the Columbia River Basalt Group were reacted in an autoclave for up to 2000 hours at temperatures and pressures to simulate in situ conditions. Changes in core porosity, secondary minerals, and solution chemistry were measured.

  15. All-fiber polarization locked vector soliton laser using carbon nanotubes.

    PubMed

    Mou, C; Sergeyev, S; Rozhin, A; Turistyn, S

    2011-10-01

    We report an all-fiber mode-locked erbium-doped fiber laser (EDFL) employing carbon nanotube (CNT) polymer composite film. By using only standard telecom grade components, without any complex polarization control elements in the laser cavity, we have demonstrated polarization locked vector solitons generation with duration of ~583 fs, average power of ~3 mW (pulse energy of 118 pJ) at the repetition rate of ~25.7 MHz.

  16. Electrochemical performance of Si anode modified with carbonized gelatin binder

    NASA Astrophysics Data System (ADS)

    Jiang, Ying; Mu, Daobin; Chen, Shi; Wu, Borong; Cheng, Kailin; Li, Luyu; Wu, Feng

    2016-09-01

    Gelatin is alternatively adopted as the binder to modify Si anode coupling with its carbonization treatment. The binder can provide good bonding and uniform dispersion of the particles besides its environmental benignancy. Importantly, the carbonized binder containing nitrogen will be advantageous to the electrical conductivity of the electrode. In addition, some spaces are formed in the electrode due to the decomposition and shrinkage of the gelatin binder during heat-treatment, which may facilitate electrolyte penetration and accommodate volume change during cycling. All these merits make contribution to the good electrochemical performance of the modified Si electrode. It exhibits a reversible capacity of 990.3 mA h g-1 after 70 cycles at a current density of 100 mA g-1 and 904 mA h g-1 after 100 cycles at 400 mA g-1.

  17. Sorption of carbon dioxide onto sodium carbonate

    SciTech Connect

    Sang-Wook Park; Deok-Ho Sung; Byoung-Sik Choi; Kwang-Joong Oh; Kil-Ho Moon

    2006-07-01

    Sodium carbonate was used as a sorbent to capture CO{sub 2} from a gaseous stream of carbon dioxide, nitrogen, and moisture. The breakthrough data of CO{sub 2} were measured in a fixed bed to observe the reaction kinetics of CO{sub 2}-carbonate reaction. Several models such as the shrinking-core model, the homogeneous model, and the deactivation model in the non-catalytic heterogeneous reaction systems were used to explain the kinetics of reaction among CO{sub 2}, Na{sub 2}CO{sub 3}, and moisture using analysis of the experimental breakthrough data. Good agreement of the deactivation model was obtained with the experimental breakthrough data. The sorption rate constant and the deactivation rate constant were evaluated by analysis of the experimental breakthrough data using a nonlinear least squares technique and described as Arrhenius form.

  18. Randomly oriented carbon/carbon composite

    NASA Astrophysics Data System (ADS)

    Raunija, Thakur Sudesh Kumar; Babu, S.

    2013-06-01

    The main objective of this study is to develop an alternate, rapid and cost effective process for the fabrication of carbon/carbon (C/C) composite. Slurry moulding technique is adopted for the fabrication of C/C composite. Randomly oriented hybrid discrete carbon fiber (CF) reinforced and mesophase pitch (MP) derived matrix C/C composite is fabricated. Process parameters are optimized and repeatability is proved. The electrical conductivity of the composite fabricated through the developed process is found to be better than that fabricated through conventional processes. The other properties are also found to be competent. The randomly oriented C/C composite because of its mouldability is found suitable for various applications which require complex shapes.

  19. Microbially mediated mineral carbonation

    NASA Astrophysics Data System (ADS)

    Power, I. M.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2010-12-01

    Mineral carbonation involves silicate dissolution and carbonate precipitation, which are both natural processes that microorganisms are able to mediate in near surface environments (Ferris et al., 1994; Eq. 1). (Ca,Mg)SiO3 + 2H2CO3 + H2O → (Ca,Mg)CO3 + H2O + H4SiO4 + O2 (1) Cyanobacteria are photoautotrophs with cell surface characteristics and metabolic processes involving inorganic carbon that can induce carbonate precipitation. This occurs partly by concentrating cations within their net-negative cell envelope and through the alkalinization of their microenvironment (Thompson & Ferris, 1990). Regions with mafic and ultramafic bedrock, such as near Atlin, British Columbia, Canada, represent the best potential sources of feedstocks for mineral carbonation. The hydromagnesite playas near Atlin are a natural biogeochemical model for the carbonation of magnesium silicate minerals (Power et al., 2009). Field-based studies at Atlin and corroborating laboratory experiments demonstrate the ability of a microbial consortium dominated by filamentous cyanobacteria to induce the precipitation of carbonate minerals. Phototrophic microbes, such as cyanobacteria, have been proposed as a means for producing biodiesel and other value added products because of their efficiency as solar collectors and low requirement for valuable, cultivable land in comparison to crops (Dismukes et al., 2008). Carbonate precipitation and biomass production could be facilitated using specifically designed ponds to collect waters rich in dissolved cations (e.g., Mg2+ and Ca2+), which would allow for evapoconcentration and provide an appropriate environment for growth of cyanobacteria. Microbially mediated carbonate precipitation does not require large quantities of energy or chemicals needed for industrial systems that have been proposed for rapid carbon capture and storage via mineral carbonation (e.g., Lackner et al., 1995). Therefore, this biogeochemical approach may represent a readily

  20. Method for Making a Carbon-Carbon Cylinder Block

    NASA Technical Reports Server (NTRS)

    Ransone, Phillip O. (Inventor)

    1997-01-01

    A method for making a lightweight cylinder block composed of carbon-carbon is disclosed. The use of carbon-carbon over conventional materials. such as cast iron or aluminum, reduces the weight of the cylinder block and improves thermal efficiency of the internal combustion reciprocating engine. Due to the negligible coefficient of thermal expansion and unique strength at elevated temperatures of carbon-carbon, the piston-to-cylinder wall clearance can be small, especially when the carbon-carbon cylinder block is used in conjunction with a carbon-carbon piston. Use of the carbon-carbon cylinder block has the effect of reducing the weight of other reciprocating engine components allowing the piston to run at higher speeds and improving specific engine performance.

  1. Interstitially protected oxidation resistant carbon-carbon composite

    SciTech Connect

    Strangman, T.E.; Keiser, R.J.

    1984-02-01

    The carbon fiber bundles in a carbon-carbon composite are protected against oxidation by coating the fiber bundles with at least one protective layer consisting of an underlayer portion of boron carbide and an overlayer portion of silicon carbide.

  2. Preliminary steps toward formation of a generalized budget for cold-water carbonates

    NASA Astrophysics Data System (ADS)

    Smith, Abigail M.

    1988-11-01

    High-latitude carbonate sediments were once considered isolated exceptions to the tropical rule. They are now being studied throughout the world and preliminary descriptive models have been proposed. Constituents, composition and distribution of cold-water carbonate sediments have been described, and they are diagnostically different from their tropical counterparts. The rates of depositional and post-depositional processes may differ as well. The present study of the rates of gross production, net production and diagenesis was undertaken at Shell Beach in the Gulf of Maine (43°45'N, 69°45'W), a shelly pocket beach. Surface and subsurface sediments were collected and analyzed for CaCO 3 content, assemblage and alteration. Population density of dominant organisms and the weight of skeletal material in typical adults were determined. Transport of sediment was observed. Gross production by dominant organisms was calculated to be 1600 g CaCO 3/m 2 y over the area of production. Net production, while less exact, was on the order of 13-130 g CaCO 3/m 2 y. The difference between these is explained by strong destructive diagenesis, dominantly biological, and at a rate of 80-1300 g CaCO 3/m 3 y. The large gap between gross and net production seems to be characteristic of cold-water carbonate sediments, as does the strongly destructive diagenesis. The gap must be remembered when assessing fossil cold-water populations.

  3. Chemical bond properties and charge transfer bands of O(2-)-Eu(3+), O(2-)-Mo(6+) and O(2-)-W(6+) in Eu(3+)-doped garnet hosts Ln3M5O12 and ABO4 molybdate and tungstate phosphors.

    PubMed

    Liu, Xiaoguang; Li, Ling; Noh, Hyeon Mi; Moon, Byung Kee; Choi, Byung Chun; Jeong, Jung Hyun

    2014-06-21

    Charge transfer (CT) energy from the ligand to the central ions is an important factor in luminescence properties for rare earth doped inorganic phosphors. The dielectric theory of complex crystals was used to calculate chemical bond properties. Combining the photoluminescence and the dielectric theory of complex crystals, the CT bands of O(2-)-Eu(3+), O(2-)-Mo(6+) and O(2-)-W(6+) for Eu(3+)-doped inorganic phosphors have been investigated experimentally and theoretically. Taking Eu(3+)-doped Ln3M5O12 (Ln = Y, Lu and M = Al, Ga), Gd3Ga5O12, MMoO4 (M = Ca, Sr, Ba) and MWO4 (M = Ca, Sr, Ba) as typical phosphors, we investigated the effects of the cation size on the CT bands and chemical bond properties including the bond length (d), the covalency (fc), the bond polarizability (αb) and the environmental factor (he) of O(2-)-Eu(3+), O(2-)-Mo(6+) and O(2-)-W(6+), respectively. For systematic isostructural Ln3M5O12 (Ln = Y, Lu and M = Al, Ga) phosphors, with the increasing M ion radius, the bond length of Ln-O decreases, but fc and αb increase, which is the main reason that the environmental factor increased. For the isostructural MMoO4:Eu, with the increasing M ion radius, the Mo-O bond length increases, but fc and αb decrease, and thus he decreases. However, in the compound system MWO4:Eu (M = Ca, Ba) with the increasing M ion radius, the O-W bond length increases, but fc and αb increase, and thus he increases and the O-W CT energy decreases. Their O(2-)-Eu(3+), O(2-)-Mo(6+) and O(2-)-W(6+) CT bands as well as their full width at half maximum (FWHM) were directly influenced by he. And with the increasing he, CT bands of O-Eu or O-Mo or O-W decrease and their FWHM increases. These results indicate a promising approach for changing the material properties, searching for new Eu(3+) doped molybdate, tungstate or other oxide phosphors and analyzing the experimental result.

  4. Trends in Syntheses, Structures, and Properties for Three Series of Ammine Rare-Earth Metal Borohydrides, M(BH4)3·nNH3 (M = Y, Gd, and Dy).

    PubMed

    Jepsen, Lars H; Ley, Morten B; Černý, Radovan; Lee, Young-Su; Cho, Young Whan; Ravnsbæk, Dorthe; Besenbacher, Flemming; Skibsted, Jørgen; Jensen, Torben R

    2015-08-03

    Fourteen solvent- and halide-free ammine rare-earth metal borohydrides M(BH4)3·nNH3, M = Y, Gd, Dy, n = 7, 6, 5, 4, 2, and 1, have been synthesized by a new approach, and their structures as well as chemical and physical properties are characterized. Extensive series of coordination complexes with systematic variation in the number of ligands are presented, as prepared by combined mechanochemistry, solvent-based methods, solid-gas reactions, and thermal treatment. This new synthesis approach may have a significant impact within inorganic coordination chemistry. Halide-free metal borohydrides have been synthesized by solvent-based metathesis reactions of LiBH4 and MCl3 (3:1), followed by reactions of M(BH4)3 with an excess of NH3 gas, yielding M(BH4)3·7NH3 (M = Y, Gd, and Dy). Crystal structure models for M(BH4)3·nNH3 are derived from a combination of powder X-ray diffraction (PXD), (11)B magic-angle spinning NMR, and density functional theory (DFT) calculations. The structures vary from two-dimensional layers (n = 1), one-dimensional chains (n = 2), molecular compounds (n = 4 and 5), to contain complex ions (n = 6 and 7). NH3 coordinates to the metal in all compounds, while BH4(-) has a flexible coordination, i.e., either as a terminal or bridging ligand or as a counterion. M(BH4)3·7NH3 releases ammonia stepwise by thermal treatment producing M(BH4)3·nNH3 (6, 5, and 4), whereas hydrogen is released for n ≤ 4. Detailed analysis of the dihydrogen bonds reveals new insight about the hydrogen elimination mechanism, which contradicts current hypotheses. Overall, the present work provides new general knowledge toward rational materials design and preparation along with limitations of PXD and DFT for analysis of structures with a significant degree of dynamics in the structures.

  5. A first-principles density functional theory study of the electronic structural and thermodynamic properties of M2ZrO3 and M2CO3 (M=Na, K) and their capabilities for CO2 capture

    SciTech Connect

    Yuhua Duan

    2012-01-01

    Alkali metal zirconates could be used as solid sorbents for CO{sub 2} capture. The structural, electronic, and phonon properties of Na{sub 2}ZrO{sub 3}, K{sub 2}ZrO{sub 3}, Na{sub 2}CO{sub 3}, and K{sub 2}CO{sub 3} are investigated by combining the density functional theory with lattice phonon dynamics. The thermodynamics of CO{sub 2} absorption/desorption reactions of these two zirconates are analyzed. The calculated results show that their optimized structures are in a good agreement with experimental measurements. The calculated band gaps are 4.339 eV (indirect), 3.641 eV (direct), 3.935 eV (indirect), and 3.697 eV (direct) for Na{sub 2}ZrO{sub 3}, K{sub 2}ZrO{sub 3}, Na{sub 2}CO{sub 3}, and K{sub 2}CO{sub 3}, respectively.The calculated phonon dispersions and phonon density of states for M{sub 2}ZrO{sub 3} and M{sub 2}CO{sub 3} (M = K, Na, Li) revealed that from K to Na to Li, their frequency peaks are shifted to high frequencies due to the molecular weight decreased from K to Li. From the calculated reaction heats and relationships of free energy change versus temperatures and CO{sub 2} pressures of the M{sub 2}ZrO{sub 3} (M = K, Na, Li) reacting with CO{sub 2}, we found that the performance of Na{sub 2}ZrO{sub 3} capturing CO{sub 2} is similar to that of Li{sub 2}ZrO{sub 3} and is better than that of K{sub 2}ZrO{sub 3}. Therefore, Na{sub 2}ZrO{sub 3} and Li{sub 2}ZrO{sub 3} are good candidates of high temperature CO{sub 2} sorbents and could be used for post combustion CO{sub 2} capture technologies.

  6. Effect of solids retention time on the bioavailability of organic carbon in anaerobically digested swine waste.

    PubMed

    Kinyua, Maureen N; Cunningham, Jeffrey; Ergas, Sarina J

    2014-06-01

    Anaerobic digestion (AD) can be used to stabilize and produce energy from livestock waste; however, digester effluents may require further treatment to remove nitrogen. This paper quantifies the effects of varying solids retention time (SRT) methane yield, volatile solids (VS) reduction and organic carbon bioavailability for denitrification during swine waste AD. Four bench-scale anaerobic digesters, with SRTs of 14, 21, 28 and 42 days, operated with swine waste feed. Effluent organic carbon bioavailability was measured using anoxic microcosms and respirometry. Excellent performance was observed for all four digesters, with >60% VS removal and CH4 yields between 0.1 and 0.3(m(3)CH4)/(kg VS added). Organic carbon in the centrate as an internal organic carbon source for denitrification supported maximum specific denitrification rates between 47 and 56(mg NO3(-)-N)/(g VSS h). The digester with the 21-day SRT had the highest CH4 yield and maximum specific denitrification rates.

  7. Activated carbon derived from waste coffee grounds for stable methane storage.

    PubMed

    Kemp, K Christian; Baek, Seung Bin; Lee, Wang-Geun; Meyyappan, M; Kim, Kwang S

    2015-09-25

    An activated carbon material derived from waste coffee grounds is shown to be an effective and stable medium for methane storage. The sample activated at 900 °C displays a surface area of 1040.3 m(2) g(-1) and a micropore volume of 0.574 cm(3) g(-1) and exhibits a stable CH4 adsorption capacity of ∼4.2 mmol g(-1) at 3.0 MPa and a temperature range of 298 ± 10 K. The same material exhibits an impressive hydrogen storage capacity of 1.75 wt% as well at 77 K and 100 kPa. Here, we also propose a mechanism for the formation of activated carbon from spent coffee grounds. At low temperatures, the material has two distinct types with low and high surface areas; however, activation at elevated temperatures drives off the low surface area carbon, leaving behind the porous high surface area activated carbon.

  8. Mesoporous carbon -Cr2O3 composite as an anode material for lithium ion batteries

    SciTech Connect

    Guo, Bingkun; Chi, Miaofang; Sun, Xiao-Guang; Dai, Sheng

    2012-01-01

    Mesoporous carbon-Cr2O3 (M-C-Cr2O3) composite was prepared by co-assembly of in-situ formed phenolic resin, chromium precursor, and Pluronic block copolymer under acidic conditions, followed by carbonization at 750oC under Argon. The TEM results confirmed that the Cr2O3 nanoparticles, ranging from 10 to 20 nm, were well dispersed in the matrix of mesoporous carbon. The composite exhibited an initial reversible capacity of 710 mAh g-1 and good cycling stability, which is mainly due to the synergic effects of carbons within the composites, i.e. confining the crystal growth of Cr2O3 during the high temperature treatment step and buffering the volume change of Cr2O3 during the cycling step. This composite material is a promising anode material for lithium ion batteries.

  9. Accidental carbon monoxide poisoning.

    PubMed

    Zeller, W P; Miele, A; Suarez, C; Hannigan, J; Hurley, R M

    1984-12-01

    In this case report of an accidental automobile carbon monoxide poisoning, we identify the following risk factors: freezing temperature, young passenger age, location in the rear of the auto, smaller patient mass, and auto disrepair. The pathogenesis of carbon monoxide poisoning is reviewed. Emergency treatment and suggested criteria for hyperbaric oxygen use in pediatric patients are discussed.

  10. Seeing the Carbon Cycle

    ERIC Educational Resources Information Center

    Drouin, Pamela; Welty, David J.; Repeta, Daniel; Engle-Belknap, Cheryl A.; Cramer, Catherine; Frashure, Kim; Chen, Robert

    2006-01-01

    In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

  11. The carbon cycle revisited

    NASA Technical Reports Server (NTRS)

    Bolin, Bert; Fung, Inez

    1992-01-01

    Discussions during the Global Change Institute indicated a need to present, in some detail and as accurately as possible, our present knowledge about the carbon cycle, the uncertainties in this knowledge, and the reasons for these uncertainties. We discuss basic issues of internal consistency within the carbon cycle, and end by summarizing the key unknowns.

  12. Carbon Dioxide and Climate.

    ERIC Educational Resources Information Center

    Brewer, Peter G.

    1978-01-01

    The amount of carbon dioxide in the atmosphere is increasing at a rate that could cause significant warming of the Earth's climate in the not too distant future. Oceanographers are studying the role of the ocean as a source of carbon dioxide and as a sink for the gas. (Author/BB)

  13. China's carbon conundrum

    NASA Astrophysics Data System (ADS)

    Qi, Ye; Wu, Tong; He, Jiankun; King, David A.

    2013-07-01

    China's carbon dioxide emissions are rising fast. Yet, per capita, gross domestic product and energy use are only a fraction of their United States equivalents. With a growing urban middle class, the trend will continue, but there is progress on the path to a low-carbon economy.

  14. Carbon Flux Explorers

    ScienceCinema

    Bishop, Jim

    2016-10-12

    Jim Bishop, senior scientist at Berkeley Lab and professor at UC Berkeley, is leading a project to deploy robotic floats that provide data on how microorganisms sequester carbon in the ocean. He recently led a research team on a 10-day voyage, funded by the National Science Foundation, to put the Carbon Flux Explorers to the test.

  15. Carbon dioxide recycling

    EPA Science Inventory

    The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the “Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

  16. Fly ash carbon passivation

    DOEpatents

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  17. Lead carbonate scintillator materials

    DOEpatents

    Derenzo, Stephen E.; Moses, William W.

    1991-01-01

    Improved radiation detectors containing lead carbonate or basic lead carbonate as the scintillator element are disclosed. Both of these scintillators have been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to other known scintillator materials. The radiation detectors disclosed are favorably suited for use in general purpose detection and in medical uses.

  18. Carbon Flux Explorers

    SciTech Connect

    Bishop, Jim

    2016-09-09

    Jim Bishop, senior scientist at Berkeley Lab and professor at UC Berkeley, is leading a project to deploy robotic floats that provide data on how microorganisms sequester carbon in the ocean. He recently led a research team on a 10-day voyage, funded by the National Science Foundation, to put the Carbon Flux Explorers to the test.

  19. Carbon Dioxide Fountain

    ERIC Educational Resources Information Center

    Kang, Seong-Joo; Ryu, Eun-Hee

    2007-01-01

    This article presents the development of a carbon dioxide fountain. The advantages of the carbon dioxide fountain are that it is odorless and uses consumer chemicals. This experiment also is a nice visual experiment that allows students to see evidence of a gaseous reagent being consumed when a pressure sensor is available. (Contains 3 figures.)…

  20. Modeling Carbon Exchange

    NASA Technical Reports Server (NTRS)

    Sellers, Piers

    2012-01-01

    Model results will be reviewed to assess different methods for bounding the terrestrial role in the global carbon cycle. It is proposed that a series of climate model runs could be scoped that would tighten the limits on the "missing sink" of terrestrial carbon and could also direct future satellite image analyses to search for its geographical location and understand its seasonal dynamics.

  1. Sustainable carbon materials.

    PubMed

    Titirici, Maria-Magdalena; White, Robin J; Brun, Nicolas; Budarin, Vitaliy L; Su, Dang Sheng; del Monte, Francisco; Clark, James H; MacLachlan, Mark J

    2015-01-07

    Carbon-based structures are the most versatile materials used in the modern field of renewable energy (i.e., in both generation and storage) and environmental science (e.g., purification/remediation). However, there is a need and indeed a desire to develop increasingly more sustainable variants of classical carbon materials (e.g., activated carbons, carbon nanotubes, carbon aerogels, etc.), particularly when the whole life cycle is considered (i.e., from precursor "cradle" to "green" manufacturing and the product end-of-life "grave"). In this regard, and perhaps mimicking in some respects the natural carbon cycles/production, utilization of natural, abundant and more renewable precursors, coupled with simpler, lower energy synthetic processes which can contribute in part to the reduction in greenhouse gas emissions or the use of toxic elements, can be considered as crucial parameters in the development of sustainable materials manufacturing. Therefore, the synthesis and application of sustainable carbon materials are receiving increasing levels of interest, particularly as application benefits in the context of future energy/chemical industry are becoming recognized. This review will introduce to the reader the most recent and important progress regarding the production of sustainable carbon materials, whilst also highlighting their application in important environmental and energy related fields.

  2. Synthesis of carbonates and related compounds from carbon dioxide via methanesulfonyl carbonates.

    PubMed

    Bratt, Mark O; Taylor, Paul C

    2003-07-11

    Carbonate anions resulting from reaction of primary or secondary alcohols with carbon dioxide, when added to methanesulfonic anhydride in cooled acetonitrile solution, yield methanesulfonyl carbonates, a new class of synthetic intermediate. Base-mediated reaction of the methanesulfonyl carbonates with alcohols, thiols, and amines yields carbonates, thiocarbonates, and carbamates, respectively. Overall yields for the three steps vary from 19% to 42%.

  3. Novel CX⋯π halogen bonds in complexes of acetylene and its derivatives of Na and MPH3 (M=Cu, Ag, Au) with XCCF (X=Cl, Br, I).

    PubMed

    Zhuo, Hongying; Liu, Mingjuan; Li, Qingzhong; Li, Wenzuo; Cheng, Jianbo

    2014-06-05

    Ab initio calculations have been carried out for a variety of model systems with a T-shaped CX⋯π motif. The CX⋯π interaction of acetylene with the halogen donor molecule XCCF (X=Cl, Br, I) is invariably found to be weak with the interaction energy less than 11kJ/mol in magnitude. Substitution of the two protons in acetylene with more electron-donating sodium atoms increases the π electron density in the CC bond and leads to a substantial enhancement in its interaction with the halogen donor. The calculated interaction energies increase to as much as 73kJ/mol in the case of C2Na2-ICCF. The interaction of XCCF with a model coinage metal ethynide, H3PMCCMPH3 (M=Cu, Ag, Au), is intermediate between these two extremes, and the interaction energy is related to the nature of coinage metals. The CX⋯π halogen bonds have been analyzed with natural bond orbital, atoms in molecules, and energy decomposition.

  4. Spin-Spin Interactions in the Oxides A(3)M'MO(6) (M = Rh, Ir; A = Ca, Sr; M' = Alkaline Earth, Zn, Cd, Na) of the K(4)CdCl(6) Structure Type Examined by Electronic Structure Calculations.

    PubMed

    Lee, K.-S.; Koo, H.-J.; Whangbo, M.-H.

    1999-05-03

    The oxides A(3)M'MO(6) (M = Rh, Ir; A = Ca, Sr; M' = alkaline earth, Zn, Cd) of the K(4)CdCl(6) structure type consist of isolated (MO(6))(8)(-) octahedral anions and exhibit an antiferromagnetic ordering at low temperatures. The spin-spin interactions in these oxides, Ca(3)NaMO(6) (M = Ir, Ru), and Sr(3)NaRuO(6) were examined by calculating how strongly the t(2g)-block levels of adjacent (MO(6))((6+)(n)()())(-) (n = 1, 2) anions interact in the presence and absence of the intervening cations A(2+) and M' (n)()(+) (n = 1, 2). Our calculations show that the spin-spin interactions in these oxides are three-dimensional, and the superexchange interactions occur mainly through the short intrachain and interchain M-O.O-M linkages. When the M(n)()(+) cation is very small compared with the A(2+) cation, the intrachain interaction is substantially stronger than the interchain interaction. The opposite is found when the sizes of the M(n)()(+) and A(2+) cations become similar.

  5. First principles static and dynamic calculations for the transition metal hydride series MH4L3 (M = Fe, Ru and Os; L = NH3, PH3 and PF3).

    PubMed

    Sieffert, Nicolas; Kendrick, Thomas; Tiana, Davide; Morrison, Carole A

    2015-03-07

    We present a first principles static and dynamical study of the transition metal hydride series MH4L3 (M = Fe, Ru and Os; L = NH3, PH3 and PF3), with a view to arriving at an understanding of how the variation in the electronic properties of the metal sites and ligands can influence the dynamics of the resulting complexes. A broad range of behaviour was observed, encompassing stable classical minima (M = Os, L = NH3 and M = Ru, L = PH3) to stable η(2)-H2 non-classical minima (M = Fe, L = PF3 and M = Ru, L = PH3 or PF3), with the other structures exhibiting dynamical behaviour that spontaneously converted between the classical and non-classical states during the molecular dynamics simulations. The importance of a small L(axial)-M-L(axial) angle in stabilising the non-classical state is highlighted, as is a short η(2)-H2···H(cis) distance in non-classical complexes that spontaneously convert to the classical form. We also investigated the changes in the electronic structure of the complex FeH4(PH3)3 during a η(2)-H2 bond breaking/bond making reaction and observed direct evidence of the 'cis effect', whereby a neighbouring hydride ligand acts to stabilise the intermediate classical state.

  6. CONDENSED MATTER: STRUCTURE, THERMAL AND MECHANICAL PROPERTIES: Structural phase transition behaviour of Zn4Sb3 and its substitutional compounds (Zn0.98M0.02)4Sb3 (M = Al, Ga and In) at low temperatures

    NASA Astrophysics Data System (ADS)

    Liu, Feng; Qin, Xiao-Ying; Liu, Mian

    2009-10-01

    Structural phase transitions of Zn4Sb3 and its substitutional compounds (Zn0.98M0.02)4Sb3 (M = Al, Ga and In) are investigated by electrical transport measurement and differential scanning calorimetry below room temperature. The results indicate that both β → α and α → α' phase transitions of Zn4Sb3 are reversible and exothermic processes, which may be explained as that both the transitions originate from the ordering of the disordered interstitial Zn and vacancies in regular sizes. The derived activation energies of β → α and α → α' phase transition processes for Zn4Sb3 are E1 = 3.9 eV and E2 = 4.1 eV, respectively. Although no remarkable influence on activation energy E2 is observed after Al doping, Al substitution for Zn causes E1 to increase to 4.6 eV, implying its suppression of β → α transition to a great extent. Moreover, it is found that both β → α and α → α' transitions are completely prohibited by substitution of either In or Ga for Zn in Zn4Sb3. The underlying mechanisms for these phenomena are discussed.

  7. Redwoods, restoration, and implications for carbon budgets

    USGS Publications Warehouse

    Madej, M.A.

    2010-01-01

    The coast redwoods (Sequoia sempervirens) of California have several unique characteristics that influence interactions between vegetation and geomorphic processes. Case studies, using a combination of in-channel wood surveys and an air photo inventory of landslides, illustrate current conditions in a redwood-dominated watershed undergoing restoration work, and the influence of wood loading and landslides on the carbon budget. Redwood trees have extremely large biomass (trunk wood volumes of 700 to 1000 m3) and are very decay-resistant; consequently, they have a large and persistent influence on in-channel wood loading. Large wood surveys indicate high wood loading in streams in uncut forests (0.3-0.5 m3/m2 of channel), but also show that high wood loading can persist in logged basin with unlogged riparian buffers because of the slow decay of fallen redwoods. Through a watershed restoration program, Redwood National Park increases in-channel wood loading in low-order streams, but the effectiveness of this technique has not yet been tested by a large flood. Another unique characteristic of redwood is its ability to resprout from basal burls after cutting, so that root strength may not decline as sharply following logging as in other types of forests. An air photo inventory of landslides following a large storm in 1997 indicated: 1) that in the Redwood Creek watershed the volume of material displaced by landslides in harvested areas was not related to the time elapsed since logging, suggesting that the loss of root strength was not a decisive factor in landslide initiation, 2) landslide production on decommissioned logging roads was half that of untreated roads, and 3) landslides removed an estimated 28 Mg of organic carbon/km2 from hillslopes. The carbon budget of a redwood-dominated catchment is dominated by the vegetative component, but is also influenced by the extent of mass movement, erosion control work, and in-channel storage of wood.

  8. The Contemporary Carbon Cycle

    NASA Astrophysics Data System (ADS)

    Houghton, R. A.

    2003-12-01

    The global carbon cycle refers to the exchanges of carbon within and between four major reservoirs: the atmosphere, the oceans, land, and fossil fuels. Carbon may be transferred from one reservoir to another in seconds (e.g., the fixation of atmospheric CO2 into sugar through photosynthesis) or over millennia (e.g., the accumulation of fossil carbon (coal, oil, gas) through deposition and diagenesis of organic matter). This chapter emphasizes the exchanges that are important over years to decades and includes those occurring over the scale of months to a few centuries. The focus will be on the years 1980-2000 but our considerations will broadly include the years ˜1850-2100. Chapter 8.09, deals with longer-term processes that involve rates of carbon exchange that are small on an annual timescale (weathering, vulcanism, sedimentation, and diagenesis).The carbon cycle is important for at least three reasons. First, carbon forms the structure of all life on the planet, making up ˜50% of the dry weight of living things. Second, the cycling of carbon approximates the flows of energy around the Earth, the metabolism of natural, human, and industrial systems. Plants transform radiant energy into chemical energy in the form of sugars, starches, and other forms of organic matter; this energy, whether in living organisms or dead organic matter, supports food chains in natural ecosystems as well as human ecosystems, not the least of which are industrial societies habituated (addicted?) to fossil forms of energy for heating, transportation, and generation of electricity. The increased use of fossil fuels has led to a third reason for interest in the carbon cycle. Carbon, in the form of carbon dioxide (CO2) and methane (CH4), forms two of the most important greenhouse gases. These gases contribute to a natural greenhouse effect that has kept the planet warm enough to evolve and support life (without the greenhouse effect the Earth's average temperature would be -33

  9. Carbon dioxide conversion over carbon-based nanocatalysts.

    PubMed

    Khavarian, Mehrnoush; Chai, Siang-Piao; Mohamed, Abdul Rahman

    2013-07-01

    The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity.

  10. Mangroves among the most carbon-rich forests in the tropics

    NASA Astrophysics Data System (ADS)

    Donato, Daniel C.; Kauffman, J. Boone; Murdiyarso, Daniel; Kurnianto, Sofyan; Stidham, Melanie; Kanninen, Markku

    2011-05-01

    Mangrove forests occur along ocean coastlines throughout the tropics, and support numerous ecosystem services, including fisheries production and nutrient cycling. However, the areal extent of mangrove forests has declined by 30-50% over the past half century as a result of coastal development, aquaculture expansion and over-harvesting. Carbon emissions resulting from mangrove loss are uncertain, owing in part to a lack of broad-scale data on the amount of carbon stored in these ecosystems, particularly below ground. Here, we quantified whole-ecosystem carbon storage by measuring tree and dead wood biomass, soil carbon content, and soil depth in 25 mangrove forests across a broad area of the Indo-Pacific region--spanning 30° of latitude and 73° of longitude--where mangrove area and diversity are greatest. These data indicate that mangroves are among the most carbon-rich forests in the tropics, containing on average 1,023Mg carbon per hectare. Organic-rich soils ranged from 0.5m to more than 3m in depth and accounted for 49-98% of carbon storage in these systems. Combining our data with other published information, we estimate that mangrove deforestation generates emissions of 0.02-0.12Pg carbon per year--as much as around 10% of emissions from deforestation globally, despite accounting for just 0.7% of tropical forest area.

  11. Carbon-fiber technology

    NASA Technical Reports Server (NTRS)

    Hansen, C. F.; Parker, J. A.

    1980-01-01

    The state of the art of PAN based carbon fiber manufacture and the science of fiber behavior is surveyed. A review is given of the stabilization by oxidation and the subsequent carbonization of fibers, of the apparent structure of fibers deduced from scanning electron microscopy, from X-ray scattering, and from similarities with soft carbons, and of the known relations between fiber properties and heat treatment temperature. A simplified model is invoked to explain the electrical properties of fibers and recent quantum chemical calculations on atomic clusters are used to elucidate some aspects of fiber conductivity. Some effects of intercalation and oxidative modification of finished fibers are summarized.

  12. Production of carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Journet, C.; Bernier, P.

    Carbon nanostructures such as single-walled and multi-walled nanotubes (SWNTs and MWNTs) or graphitic polyhedral nanoparticles can be produced using various methods. Most of them are based on the sublimation of carbon under an inert atmosphere, such as the electric arc discharge process, the laser ablation method, or the solar technique. But chemical methods can also be used to synthesize these kinds of carbon materials: the catalytic decomposition of hydrocarbons, the production by electrolysis, the heat treatment of a polymer, the low temperature solid pyrolysis, or the in situ catalysis.

  13. Improving Carbon Fixation Pathways

    PubMed Central

    Ducat, Daniel C.

    2012-01-01

    A recent resurgence in basic and applied research on photosynthesis has been driven in part by recognition that fulfilling future food and energy requirements will necessitate improvements in crop carbon-fixation efficiencies. Photosynthesis in traditional terrestrial crops is being reexamined in light of molecular strategies employed by photosynthetic microbes to enhance the activity of the Calvin cycle. Synthetic biology is well-situated to provide original approaches for compartmentalizing and enhancing photosynthetic reactions in a species independent manner. Furthermore, the elucidation of alternative carbon-fixation routes distinct from the Calvin cycle raises possibilities that alternative pathways and organisms can be utilized to fix atmospheric carbon dioxide into useful materials. PMID:22647231

  14. Nanotailored Carbon Fibers

    DTIC Science & Technology

    2009-06-07

    Chae, Han Gi, Ph.D. Nano Engineered Materials Corporation 2349 Lake Forest Trail Lawrenceville, GA 30043 Air Force Office of Scientific...0065, AF08‐T028  Nanotailored Carbon Fibers  Nano  Engineered Materials Corp    Nanotailored Carbon Fibers (STTR Phase I final technical report...14   FA9550‐08‐C‐0065, AF08‐T028  Nanotailored Carbon Fibers  Nano

  15. IMPACCT: Carbon Capture Technology

    SciTech Connect

    2012-01-01

    IMPACCT Project: IMPACCT’s 15 projects seek to develop technologies for existing coal-fired power plants that will lower the cost of carbon capture. Short for “Innovative Materials and Processes for Advanced Carbon Capture Technologies,” the IMPACCT Project is geared toward minimizing the cost of removing carbon dioxide (CO2) from coal-fired power plant exhaust by developing materials and processes that have never before been considered for this application. Retrofitting coal-fired power plants to capture the CO2 they produce would enable greenhouse gas reductions without forcing these plants to close, shifting away from the inexpensive and abundant U.S. coal supply.

  16. Impacts of Land Cover Change on the Carbon Dynamics in Indonesian Tropical Forested Wetlands- Mangroves and Peat Swamp Forests

    NASA Astrophysics Data System (ADS)

    Kauffman, J. B.; Arifanti, V. B.; Basuki, I.; Kurnianto, S.; Novita, N.; Murdiyarso, D.

    2014-12-01

    Tropical wetland forests including mangroves and lowland peat swamp forests contain among the highest carbon stocks of any ecosystem on the planet. This is largely due to the accumulation of deep organic rich soils which have been sequestering carbon for millennia. Depth of organic layers (peats) can exceed 3 m in mangrove and 10 m in the peat swamp forests. The ecosystem carbon stocks may exceed 2000 Mg/ha in mangroves and 5000 Mg/ha in peat swamp forests. Ironically, rates of deforestation of these tropical forests are among the highest in the tropics. With land cover change comes dramatic shifts in carbon stocks, net ecosystem productivity, and greenhouse gas emissions. Land cover change results in carbon losses of practically all aboveground pools as well as losses arising from soil pools. Based upon studies where we have compared stock changes due to land use the carbon emissions arising from land cover change to shrimp ponds and oil palm have ranged from 800-3000 Mg CO2e/ha. The lowered carbon sequestration rates coupled with increased or similar emissions from decomposition results in an ecosystem shift from a carbon sink to a carbon source. Clearly the large carbon stocks, high rates of deforestation, and large emissions resulting from their degradation suggest that these ecosystems should receive great consideration in climate change mitigation and adaptation strategies.

  17. Coaxial fiber supercapacitor using all-carbon material electrodes.

    PubMed

    Le, Viet Thong; Kim, Heetae; Ghosh, Arunabha; Kim, Jaesu; Chang, Jian; Vu, Quoc An; Pham, Duy Tho; Lee, Ju-Hyuck; Kim, Sang-Woo; Lee, Young Hee

    2013-07-23

    We report a coaxial fiber supercapacitor, which consists of carbon microfiber bundles coated with multiwalled carbon nanotubes as a core electrode and carbon nanofiber paper as an outer electrode. The ratio of electrode volumes was determined by a half-cell test of each electrode. The capacitance reached 6.3 mF cm(-1) (86.8 mF cm(-2)) at a core electrode diameter of 230 μm and the measured energy density was 0.7 μWh cm(-1) (9.8 μWh cm(-2)) at a power density of 13.7 μW cm(-1) (189.4 μW cm(-2)), which were much higher than the previous reports. The change in the cyclic voltammetry characteristics was negligible at 180° bending, with excellent cycling performance. The high capacitance, high energy density, and power density of the coaxial fiber supercapacitor are attributed to not only high effective surface area due to its coaxial structure and bundle of the core electrode, but also all-carbon materials electrodes which have high conductivity. Our coaxial fiber supercapacitor can promote the development of textile electronics in near future.

  18. Resistivity of Carbon-Carbon Composites Halved

    NASA Technical Reports Server (NTRS)

    Gaier, James R.

    2004-01-01

    Carbon-carbon composites have become the material of choice for applications requiring strength and stiffness at very high temperatures (above 2000 C). These composites comprise carbon or graphite fibers embedded in a carbonized or graphitized matrix. In some applications, such as shielding sensitive electronics in very high temperature environments, the performance of these materials would be improved by lowering their electrical resistivity. One method to lower the resistivity of the composites is to lower the resistivity of the graphite fibers, and a proven method to accomplish that is intercalation. Intercalation is the insertion of guest atoms or molecules into a host lattice. In this study the host fibers were highly graphitic pitch-based graphite fibers, or vapor-grown carbon fibers (VGCF), and the intercalate was bromine. Intercalation compounds of graphite are generally thought of as being only metastable, but it has been shown that the residual bromine graphite fiber intercalation compound is remarkably stable, resisting decomposition even at temperatures at least as high as 1000 C. The focus of this work was to fabricate composite preforms, determine whether the fibers they were made from were still intercalated with bromine after processing, and determine the effect on composite resistivity. It was not expected that the resistivity would be lowered as dramatically as with graphite polymer composites because the matrix itself would be much more conductive, but it was hoped that the gains would be substantial enough to warrant its use in high-performance applications. In a collaborative effort supporting a Space Act Agreement between the NASA Glenn Research Center and Applied Sciences, Inc. (Cedarville, OH), laminar preforms were fabricated with pristine and bromine-intercalated pitch-based fibers (P100 and P100-Br) and VGCF (Pyro I and Pyro I-Br). The green preforms were carbonized at 1000 C and then heat treated to 3000 C. To determine whether the

  19. Constraints on the Distance Moduli, Helium and Metal Abundances, and Ages of Globular Clusters from their RR Lyrae and Non-variable Horizontal-branch Stars. I. M3, M15, and M92

    NASA Astrophysics Data System (ADS)

    VandenBerg, Don A.; Denissenkov, P. A.; Catelan, Márcio

    2016-08-01

    Up-to-date isochrones, zero-age horizontal-branch (ZAHB) loci, and evolutionary tracks for core He-burning stars are applied to the color-magnitude diagrams of M3, M15, and M92, focusing in particular on their RR Lyrae populations. Periods for the ab- and c-type variables are calculated using the latest theoretical calibrations of {log} {P}{ab} and {log} {P}c as a function of luminosity, mass, effective temperature ({T}{{eff}}), and metallicity. Our models are generally able to reproduce the measured periods to well within the uncertainties implied by the stellar properties on which pulsation periods depend, as well as the mean periods and cluster-to-cluster differences in < {P}{ab}> and < {P}c> , on the assumption of well-supported values of E(B-V), {(m-M)}V, and [Fe/H]. While many of RR Lyrae in M3 lie close to the same ZAHB that fits the faintest horizontal-branch (HB) stars at bluer or redder colors, the M92 variables are all significantly evolved stars from ZAHB locations on the blue side of the instability strip. M15 appears to contain a similar population of HB stars as M92, along with additional helium-enhanced populations not present in the latter which comprise most of its RR Lyrae stars. The large number of variables in M15 and the similarity of the observed values of < {P}{ab}> and < {P}c> in M15 and M92 can be explained by HB models that allow for variations in Y. Similar ages (˜12.5 Gyr) are found for all three clusters, making them significantly younger than the field halo subgiant HD 140283. Our analysis suggests a preference for stellar models that take diffusive processes into account.

  20. A novel carbon fiber based porous carbon monolith

    SciTech Connect

    Burchell, T.D.; Klett, J.W.; Weaver, C.E.

    1995-07-01

    A novel porous carbon material based on carbon fibers has been developed. The material, when activated, develops a significant micro- or mesopore volume dependent upon the carbon fiber type utilized (isotropic pitch or polyacrylonitrile). The materials will find applications in the field of fluid separations or as a catalyst support. Here, the manufacture and characterization of our porous carbon monoliths are described.

  1. Pistons and Cylinders Made of Carbon-Carbon Composite Materials

    NASA Technical Reports Server (NTRS)

    Rivers, H. Kevin (Inventor); Ransone, Philip O. (Inventor); Northam, G. Burton (Inventor); Schwind, Francis A. (Inventor)

    2000-01-01

    An improved reciprocating internal combustion engine has a plurality of engine pistons, which are fabricated from carbon-carbon composite materials, in operative association with an engine cylinder block, or an engine cylinder tube, or an engine cylinder jug, all of which are also fabricated from carbon-carbon composite materials.

  2. 46 CFR 151.50-41 - Carbon disulfide (carbon bisulfide).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Carbon disulfide (carbon bisulfide). 151.50-41 Section... CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-41 Carbon disulfide (carbon bisulfide). (a) All openings shall be in the top of the tank. (b) Loading lines...

  3. 46 CFR 151.50-41 - Carbon disulfide (carbon bisulfide).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Carbon disulfide (carbon bisulfide). 151.50-41 Section... CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-41 Carbon disulfide (carbon bisulfide). (a) All openings shall be in the top of the tank. (b) Loading lines...

  4. 46 CFR 151.50-41 - Carbon disulfide (carbon bisulfide).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Carbon disulfide (carbon bisulfide). 151.50-41 Section... CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-41 Carbon disulfide (carbon bisulfide). (a) All openings shall be in the top of the tank. (b) Loading lines...

  5. 46 CFR 151.50-41 - Carbon disulfide (carbon bisulfide).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Carbon disulfide (carbon bisulfide). 151.50-41 Section... CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-41 Carbon disulfide (carbon bisulfide). (a) All openings shall be in the top of the tank. (b) Loading lines...

  6. Activity and stability of immobilized carbonic anhydrase for promoting CO2 absorption into a carbonate solution for post-combustion CO2 capture

    USGS Publications Warehouse

    Zhang, S.; Zhang, Z.; Lu, Y.; Rostam-Abadi, M.; Jones, A.

    2011-01-01

    An Integrated Vacuum Carbonate Absorption Process (IVCAP) currently under development could significantly reduce the energy consumed when capturing CO2 from the flue gases of coal-fired power plants. The biocatalyst carbonic anhydrase (CA) has been found to effectively promote the absorption of CO2 into the potassium carbonate solution that would be used in the IVCAP. Two CA enzymes were immobilized onto three selected support materials having different pore structures. The thermal stability of the immobilized CA enzymes was significantly greater than their free counterparts. For example, the immobilized enzymes retained at least 60% of their initial activities after 90days at 50??C compared to about 30% for their free counterparts under the same conditions. The immobilized CA also had significantly improved resistance to concentrations of sulfate (0.4M), nitrate (0.05M) and chloride (0.3M) typically found in flue gas scrubbing liquids than their free counterparts. ?? 2011 Elsevier Ltd.

  7. Authigenic Carbonate and the History of the Global Carbon Cycle

    NASA Astrophysics Data System (ADS)

    Schrag, Daniel P.; Higgins, John. A.; Macdonald, Francis A.; Johnston, David T.

    2013-02-01

    We present a framework for interpreting the carbon isotopic composition of sedimentary rocks, which in turn requires a fundamental reinterpretation of the carbon cycle and redox budgets over Earth's history. We propose that authigenic carbonate, produced in sediment pore fluids during early diagenesis, has played a major role in the carbon cycle in the past. This sink constitutes a minor component of the carbon isotope mass balance under the modern, high levels of atmospheric oxygen but was much larger in times of low atmospheric O2 or widespread marine anoxia. Waxing and waning of a global authigenic carbonate sink helps to explain extreme carbon isotope variations in the Proterozoic, Paleozoic, and Triassic.

  8. A novel carbon fiber based porous carbon monolith

    SciTech Connect

    Burchell, T.D.; Klett, J.W.; Weaver, C.E.

    1995-06-01

    A novel porous carbon material based on carbon fibers has been developed. The material, when activated, develops a significant micro- or mesopore volume dependent upon the carbon fiber type utilized (isotropic pitch or polyacrylonitrile). The materials will find applications in the field of fluid separations or as a catalyst support. Here, the manufacture and characterization of our porous carbon monoliths are described. A novel adsorbent carbon composite material has been developed comprising carbon fibers and a binder. The material, called carbon fiber composite molecular sieve (CFCMS), was developed through a joint research program between Oak Ridge National Laboratory (ORNL) and the University of Kentucky, Center for Applied Energy Research (UKCAER).

  9. Hypervelocity technology carbon/carbon testing

    NASA Astrophysics Data System (ADS)

    Anselmo, John V.; Kretz, Lawrence O.

    The paper describes the procedures used at the Structures Test Laboratory of the Wright Laboratory's Flight Dynamics Directorate to test a carbon/carbon hot structure representing a typical hypersonic gliding body, and presents the results of tests. The forebody was heated to 1371 C over 13 test runs, using radiant quartz lamps; a vertical shear force of 5.34 kN was introduced to the nose at a stabilized temperature of 816 C. Test data were collected using prototype high-temperature strain gages, in-house-designed high-temperature extensometers, conventional strain gages, and thermocouples. Video footage was taken of all test runs. Test runs were successfully completed up to 1371 C with flight typical thermal gradients at heating rates up to 5.56 C/sec. Results showed that, overall, the termal test control systems performed as predicted and that test temperatures and thermal gradients were achieved to within about 5 percent in most cases.

  10. Determination of 210Pb, 210Po, 226Ra, 228Ra and uranium isotopes in drinking water in order to comply with the requirements of the EU ‘Drinking Water Directive.

    PubMed

    Vasile, M; Loots, H; Jacobs, K; Verheyen, L; Sneyers, L; Verrezen, F; Bruggeman, M

    2016-03-01

    The European Union published in 2013 a new Drinking Water Directive with stricter requirements for measuring natural radioactivity. In order to adhere to this, a method for sequential separation of 210Pb, 210Po, 238U and 234U in drinking water was applied using UTEVA® and Sr resins. Polonium-210, 238U and 234U were quantified using alpha-particle spectrometry and 210Pb using liquid scintillation counting. Radium-226 and 228Ra were determined using 3M Empore Radium RAD Disks, and their quantification was done using a Quantulus™ 1220 liquid scintillation counter.

  11. Estimating carbon monoxide exposure

    NASA Technical Reports Server (NTRS)

    Edgerley, R. H.

    1971-01-01

    Method predicts effects of carbon monoxide on astronauts confined in spacecraft cabin atmospheres. Information on need for low toxicity level also applies to confined spaces. Benefits are applicable to industry and public health.

  12. Hemotoxicity of carbon nanotubes.

    PubMed

    Bussy, Cyrill; Methven, Laura; Kostarelos, Kostas

    2013-12-01

    Carbon nanotubes may enter into the bloodstream and interact with blood components indirectly via translocation following unintended exposure or directly after an intended administration for biomedical purposes. Once introduced into systemic circulation, nanotubes will encounter various proteins, biomolecules or cells which have specific roles in the homeostasis of the circulatory system. It is therefore essential to determine whether those interactions will lead to adverse effects or not. Advances in the understanding of how carbon nanotubes interact with blood proteins, the complement system, red blood cells and the hemostatic system are reviewed in this article. While many studies on carbon nanotube health risk assessment and their biomedical applications have appeared in the last few years, reports on the hemocompatibility of these nanomaterials remain surprisingly limited. Yet, defining the hemotoxicological profile is a mandatory step toward the development of clinically-relevant medications or contrast agents based on carbon nanotubes.

  13. Potassium carbonate poisoning

    MedlinePlus

    ... is a white powder used to make soap, glass, and other items. This article discusses poisoning from ... Potassium carbonate is found in: Glass Some dishwasher soaps Some ... that is used in fertilizers) Some home permanent-wave solutions ...

  14. Carbon monoxide poisoning

    MedlinePlus

    ... any major gas-burning appliances (such as a furnace or water heater). Many carbon monoxide poisonings occur in the winter months when furnaces, gas fireplaces, and portable heaters are being used ...

  15. Transport in Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Datta, S.; Xue, Yong-Qinag; Anantram, M. P.; Saini, Subhash (Technical Monitor)

    1999-01-01

    This presentation discusses coupling between carbon nanotubes (CNT), simple metals (FEG) and a graphene sheet. The graphene sheet did not couple well with FEG, but the combination of a graphene strip and CNT did couple well with most simple metals.

  16. Carbon monoxide intoxication

    SciTech Connect

    Kales, S.N. )

    1993-11-01

    Carbon monoxide poisoning usually results from inhalation of exhaust fumes from motor vehicles, smoke from fires or fumes from faulty heating systems. Carbon monoxide has a high affinity for hemoglobin, with which it forms carboxyhemoglobin. The resulting decrease in both oxygen-carrying capacity and oxygen release can lead to end-organ hypoxia. The clinical presentation is nonspecific. Headache, dizziness, fatigue and nausea are common in mild to moderate carbon monoxide poisoning. In more severe cases, tachycardia, tachypnea and central nervous system depression occur. When carbon monoxide intoxication is suspected, empiric treatment with 100 percent oxygen should be initiated immediately. The diagnosis is confirmed by documenting an elevated carboxyhemoglobin level. Hyperbaric oxygen therapy is recommended in patients with neurologic dysfunction, cardiac dysfunction or a history of unconsciousness. 26 refs.

  17. [Particle therapy: carbon ions].

    PubMed

    Pommier, Pascal; Hu, Yi; Baron, Marie-Hélène; Chapet, Olivier; Balosso, Jacques

    2010-07-01

    Carbon ion therapy is an innovative radiation therapy. It has been first proposed in the forties by Robert Wilson, however the first dedicated centres for human care have been build up only recently in Japan and Germany. The interest of carbon ion is twofold: 1) the very sharp targeting of the tumour with the so called spread out Bragg peak that delivers most of the beam energy in the tumour and nothing beyond it, sparing very efficiently the healthy tissues; 2) the higher relative biological efficiency compared to X rays or protons, able to kill radioresistant tumour cells. Both properties make carbon ions the elective therapy for non resectable radioresistant tumours loco-regionally threatening. The technical and clinical experience accumulated during the recent decades is summarized in this paper along with a detailed presentation of the elective indications. A short comparison between conventional radiotherapy and hadrontherapy is proposed for the indications which are considered as priority for carbon ions.

  18. Carbon nanotubes: Fibrillar pharmacology

    NASA Astrophysics Data System (ADS)

    Kostarelos, Kostas

    2010-10-01

    The mechanisms by which chemically functionalized carbon nanotubes flow in blood and are excreted through the kidneys illustrate the unconventional behaviour of these fibrillar nanostructures, and the opportunities they offer as components for the design of advanced delivery vehicles.

  19. Green Carbon, Black Carbon, White Carbon: Simultaneous Differentiation Between Soil Organic Matter, Pyrogenic Carbon and Carbonates Using Thermal Analysis Techniques

    NASA Astrophysics Data System (ADS)

    Plante, A. F.; Peltre, C.; Chan, J.; Baumgartl, T.; Erskine, P.; Apesteguía, M.; Virto, I.

    2014-12-01

    Quantification of soil carbon stocks and fluxes continues to be an important endeavor in assessments of soil quality, and more broadly in assessments of ecosystem functioning. The quantification of soil carbon in alkaline, carbonate-containing soils, such as those found in Mediterranean areas, is complicated by the need to differentiate between organic carbon (OC) and inorganic carbon (IC), which continues to present methodological challenges. Acidification is frequently used to eliminate carbonates prior to soil OC quantification, but when performed in the liquid phase, can promote the dissolution and loss of a portion of the OC. Acid fumigation (AF) is increasingly preferred for carbonate removal, but its effectiveness is difficult to assess using conventional elemental and isotopic analyses. The two-step approach is time, labor and cost intensive, and generates additional uncertainties from the calculations. Quantification of the actively cycling pool of soil organic C (SOC) in many soils is further complicated by the potential presence of more recalcitrant/stable forms such as pyrogenic or black carbon (BC) derived from incomplete combustion of vegetation, or even geogenic carbon such as coal. The wide spectrum of materials currently considered BC makes its quantification challenging. The chemical method using benzene polycarboxylic acids (BPCAs) as markers of condensed aromatic structures indicative of pyrogenic C is highly time, labor and cost intensive, and can generate artifacts. Several research groups are now developing method for the simultaneous identification and quantification of these various forms of soil carbon using thermal analysis techniques such as thermogravimetry, differential scanning calorimetry and evolved gas analysis. The objective of this presentation is to provide a general overview and specific examples of the current progress and technical challenges in this evolving methodology.

  20. Lead carbonate scintillator materials

    DOEpatents

    Derenzo, S.E.; Moses, W.W.

    1991-05-14

    Improved radiation detectors containing lead carbonate or basic lead carbonate as the scintillator element are disclosed. Both of these scintillators have been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to other known scintillator materials. The radiation detectors disclosed are favorably suited for use in general purpose detection and in medical uses. 3 figures.

  1. Carbon dioxide removal process

    DOEpatents

    Baker, Richard W.; Da Costa, Andre R.; Lokhandwala, Kaaeid A.

    2003-11-18

    A process and apparatus for separating carbon dioxide from gas, especially natural gas, that also contains C.sub.3+ hydrocarbons. The invention uses two or three membrane separation steps, optionally in conjunction with cooling/condensation under pressure, to yield a lighter, sweeter product natural gas stream, and/or a carbon dioxide stream of reinjection quality and/or a natural gas liquids (NGL) stream.

  2. Plant Carbonic Anhydrases

    PubMed Central

    Atkins, C. A.; Patterson, B. D.; Graham, D.

    1972-01-01

    On the basis of polyacrylamide gradient gel electrophoresis of leaf extracts from 24 species of higher plants, two main forms of carbonic anhydrase (EC 4.2.1.1) were recognized; the “dicotyledon” type and the “monocotyledon” type. More than one band of enzyme was found on gels from most species, suggesting the possibility of carbonic anhydrase isoenzymes in higher plants. Images PMID:16658144

  3. Applications for alliform carbon

    DOEpatents

    Gogotsi, Yury; Mochalin, Vadym; McDonough, IV, John Kenneth; Simon, Patrice; Taberna, Pierre Louis

    2017-02-21

    This invention relates to novel applications for alliform carbon, useful in conductors and energy storage devices, including electrical double layer capacitor devices and articles incorporating such conductors and devices. Said alliform carbon particles are in the range of 2 to about 20 percent by weight, relative to the weight of the entire electrode. Said novel applications include supercapacitors and associated electrode devices, batteries, bandages and wound healing, and thin-film devices, including display devices.

  4. Method for synthesizing carbon nanotubes

    DOEpatents

    Fan, Hongyou

    2012-09-04

    A method for preparing a precursor solution for synthesis of carbon nanomaterials, where a polar solvent is added to at least one block copolymer and at least one carbohydrate compound, and the precursor solution is processed using a self-assembly process and subsequent heating to form nanoporous carbon films, porous carbon nanotubes, and porous carbon nanoparticles.

  5. Carbonization of petroleum feedstocks

    SciTech Connect

    Eser, S.

    1987-01-01

    The properties of the petroleum cokes are determined by their crystalline structure, which principally depends on the nature of the mesophase formed during the liquid-phase carbonization of the precursors. This study was aimed at investigating the relationships between the chemical nature of the petroleum feedstocks and the mesophase development during carbonization. Ashland 240 pitch and a range of petroleum heavy residua were characterized by solvent fractionation, elemental analysis, Fourier Transform Infrared Spectroscopy, H and TC Nuclear Magnetic Resonance Spectroscopy. The semi-coke (pyridine insolubles) formation from the feedstocks and their asphaltene fractions was found to be first-order with respect to the concentration of pyridine solubles over a wide conversion range. An inverse relationship was observed between the rate of carbonization of the asphaltenes and the degree of mesophase development. The degree of mesophase development during the carbonization of the feedstock asphaltenes increased consistently with the increasing hydrogen aromaticity over the whole range of the feedstocks used. The principal conclusion from this study is that the mesophase development during carbonization critically depends on the chemical constitution of the petroleum feedstocks. The molecular nature of the asphaltene fractions determines the extent of mesophase development during the carbonization of the petroleum heavy residua. In this respect, the hydrogen aromaticity of the asphaltenes appears to be a good measure for the feedstock quality in terms of resulting coke structure and properties.

  6. Carbon Characterization Laboratory Report

    SciTech Connect

    David Swank; William Windes; D.C. Haggard; David Rohrbaugh; Karen Moore

    2009-03-01

    The newly completed Idaho National Laboratory (INL) Carbon Characterization Laboratory (CCL) is located in Lab-C20 of the Idaho National Laboratory Research Center. This laboratory was established under the Next Generation Nuclear Plant (NGNP) Project to support graphite research and development activities. The CCL is designed to characterize and test carbon-based materials such as graphite, carbon-carbon composites, and silicon-carbide composite materials. The laboratory is fully prepared to measure material properties for nonirradiated carbon-based materials. Plans to establish the laboratory as a radiological facility within the next year are definitive. This laboratory will be modified to accommodate irradiated materials, after which it can be used to perform material property measurements on both irradiated and nonirradiated carbon-based material. Instruments, fixtures, and methods are in place for preirradiation measurements of bulk density, thermal diffusivity, coefficient of thermal expansion, elastic modulus, Young’s modulus, Shear modulus, Poisson ratio, and electrical resistivity. The measurement protocol consists of functional validation, calibration, and automated data acquisition.

  7. Carbon based prosthetic devices

    SciTech Connect

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T.; Klawitter, J.J.; Ogilvie, W.; Strzepa, P.; Cook, S.D.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  8. Method of manufacturing carbon nanotubes

    NASA Technical Reports Server (NTRS)

    Benavides, Jeanette M. (Inventor); Leidecker, Henning W. (Inventor); Frazier, Jeffrey (Inventor)

    2004-01-01

    A process for manufacturing carbon nanotubes, including a step of inducing electrical current through a carbon anode and a carbon cathode under conditions effective to produce the carbon nanotubes, wherein the carbon cathode is larger than the carbon anode. Preferably, a welder is used to induce the electrical current via an arc welding process. Preferably, an exhaust hood is placed on the anode, and the process does not require a closed or pressurized chamber. The process provides high-quality, single-walled carbon nanotubes, while eliminating the need for a metal catalyst.

  9. Tracking the migration of the Indian continent using the carbonate clumped isotope technique on Phanerozoic soil carbonates

    PubMed Central

    Ghosh, Prosenjit; Vasiliev, Mikhail V.; Ghosh, Parthasarathi; Sarkar, Soumen; Ghosh, Sampa; Yamada, Keita; Ueno, Yuichiro; Yoshida, Naohiro; Poulsen, Christopher J.

    2016-01-01

    Approximately 140 million years ago, the Indian plate separated from Gondwana and migrated by almost 90° latitude to its current location, forming the Himalayan-Tibetan system. Large discrepancies exist in the rate of migration of Indian plate during Phanerozoic. Here we describe a new approach to paleo-latitudinal reconstruction based on simultaneous determination of carbonate formation temperature and δ18O of soil carbonates, constrained by the abundances of 13C-18O bonds in palaeosol carbonates. Assuming that the palaeosol carbonates have a strong relationship with the composition of the meteoric water, δ18O carbonate of palaeosol can constrain paleo-latitudinal position. Weighted mean annual rainfall δ18O water values measured at several stations across the southern latitudes are used to derive a polynomial equation: δ18Ow = −0.006 × (LAT)2 − 0.294 × (LAT) − 5.29 which is used for latitudinal reconstruction. We use this approach to show the northward migration of the Indian plate from 46.8 ± 5.8°S during the Permian (269 M.y.) to 30 ± 11°S during the Triassic (248 M.y.), 14.7 ± 8.7°S during the early Cretaceous (135 M.y.), and 28 ± 8.8°S during the late Cretaceous (68 M.y.). Soil carbonate δ18O provides an alternative method for tracing the latitudinal position of Indian plate in the past and the estimates are consistent with the paleo-magnetic records which document the position of Indian plate prior to 135 ± 3 M.y. PMID:26931069

  10. Tracking the migration of the Indian continent using the carbonate clumped isotope technique on Phanerozoic soil carbonates

    NASA Astrophysics Data System (ADS)

    Ghosh, Prosenjit; Vasiliev, Mikhail V.; Ghosh, Parthasarathi; Sarkar, Soumen; Ghosh, Sampa; Yamada, Keita; Ueno, Yuichiro; Yoshida, Naohiro; Poulsen, Christopher J.

    2016-03-01

    Approximately 140 million years ago, the Indian plate separated from Gondwana and migrated by almost 90° latitude to its current location, forming the Himalayan-Tibetan system. Large discrepancies exist in the rate of migration of Indian plate during Phanerozoic. Here we describe a new approach to paleo-latitudinal reconstruction based on simultaneous determination of carbonate formation temperature and δ18O of soil carbonates, constrained by the abundances of 13C-18O bonds in palaeosol carbonates. Assuming that the palaeosol carbonates have a strong relationship with the composition of the meteoric water, δ18O carbonate of palaeosol can constrain paleo-latitudinal position. Weighted mean annual rainfall δ18O water values measured at several stations across the southern latitudes are used to derive a polynomial equation: δ18Ow = -0.006 × (LAT)2 - 0.294 × (LAT) - 5.29 which is used for latitudinal reconstruction. We use this approach to show the northward migration of the Indian plate from 46.8 ± 5.8°S during the Permian (269 M.y.) to 30 ± 11°S during the Triassic (248 M.y.), 14.7 ± 8.7°S during the early Cretaceous (135 M.y.), and 28 ± 8.8°S during the late Cretaceous (68 M.y.). Soil carbonate δ18O provides an alternative method for tracing the latitudinal position of Indian plate in the past and the estimates are consistent with the paleo-magnetic records which document the position of Indian plate prior to 135 ± 3 M.y.

  11. Implications of carbon dust emission for terrestrail carbon cycling and carbon accounting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wind erosion preferentially removes the finest carbon- and nutrient-rich soil fractions, and consequently its role may be significant within terrestrial carbon (C) cycles. However, the impacts of wind erosion on soil organic carbon (SOC) redistribution are not considered in most carbon cycle models,...

  12. Late Quaternary strata and carbon burial records in the Yellow River delta, China

    NASA Astrophysics Data System (ADS)

    Zhao, Guangming; Ye, Siyuan; Li, Guangxue; Ding, Xigui; Yuan, Hongming

    2015-06-01

    Sediment carbon sequestration plays an essential role in mitigating atmospheric CO2 increases and the subsequently global greenhouse effect. To clarify the late Quaternary strata and carbon burial records in Yellow River delta (YRD), detailed analysis of benthic foraminifera, total carbon (TC), organic carbon (Corg), sedimentary characteristics and moisture contents of sediments, was performed on core ZK3, 30.3 m in length and obtained from YRD in 2007. Eight depositional units (designated U1-U8 in ascending order) were identified. A comprehensive analysis method of historical geography and sedimentary geology was used to determine the precise depositional ages of the modern Yellow River delta (MYRD), from which pre-MYRD ages were deduced. The results indicates that the maximum burial rates of TC, inorganic carbon (IC) and Corg occurred in the delta front (U5), and the minimum in the shallow sea (U3). Remarkable high sedimentation rates in the MYRD are responsible for burial efficiency of carbon, with an average rate of Corg burial reaching 2087±251 g (m2 yr)-1, and that of IC reaching 13741±808 g (m2 yr)-1, which are much higher than those of other regions with high contents of Corg. Therefore, YRD has a significant burial efficiency for carbon sequestration.

  13. Preparation of sludge-based activated carbon and its application in dye wastewater treatment.

    PubMed

    Wang, Xiaoning; Zhu, Nanwen; Yin, Bingkui

    2008-05-01

    A novel activation process was adopted to produce highly porous activated carbon from cyclic activated sludge in secondary precipitator in municipal wastewater treatment plant for dye removal from colored wastewater. The physical properties of activated carbon produced with the activation of 3M KOH solution in the atmosphere of steam were investigated. Adsorption removal of a dye, Acid Brilliant Scarlet GR, from aqueous solution onto the sludge-based activated carbon was studied under varying conditions of adsorption time, initial concentration, carbon dosage and pH. Adsorption equilibrium was obtained in 15 min for the dye initial concentration of 300 mg/L. Initial pH of solution had an insignificant impact on the dye removal. Results indicated that 99.7% coloration and 99.6% total organic carbon (TOC) were removed after 15 min adsorption in the synthetic solution of Acid Brilliant Scarlet GR with initial concentration of 300 mg/L of the dye and 20 g/L activated carbon. The Langmuir and Freundlich equilibrium isotherm models fitted the adsorption data well with R(2)=0.996 and 0.912, respectively. Accordingly, it is concluded that the procedure of developing activated carbon used in this study could be effective and practical for utilizing in dye wastewater treatment.

  14. WESTCARB Carbon Atlas

    DOE Data Explorer

    The West Coast Regional Carbon Sequestration Partnership (known as WESTCARB) was established in Fall 2003. It is one of seven research partnerships co-funded by DOE to characterize regional carbon sequestration opportunities and conduct pilot-scale validation tests. The California Energy Commission manages WESTCARB and is a major co-funder. WESTCARB is characterizing the extent and capacity of geologic formations capable of storing CO2, known as sinks. Results are entered into a geographic information system (GIS) database, along with the location of major CO2-emitting point sources in each of the six WESTCARB states, enabling researchers and the public to gauge the proximity of candidate CO2 storage sites to emission sources and the feasibility of linking them via pipelines. Specifically, the WESTCARB GIS database (also known as the carbon atlas) stores layers of geologic information about potential underground storage sites, such as porosity and nearby fault-lines and aquifers. Researchers use these data, along with interpreted geophysical data and available oil and gas well logs to estimate the region's potential geologic storage capacity. The database also depicts existing pipeline routes and rights-of-way and lands that could be off-limits, which can aid the development of a regional carbon management strategy. The WESTCARB Carbon Atlas, which is accessible to the public, provides a resource for public discourse on practical solutions for regional CO2 management. A key WESTCARB partner, the Utah Automated Geographic Reference Center, has developed data serving procedures to enable the WESTCARB Carbon Atlas to be integrated with those from other regional partnerships, thereby supporting the U.S. Department of Energy's national carbon atlas, NATCARB

  15. Hexagon-preserving carbon foams: Properties of hypothetical carbon allotropes

    NASA Astrophysics Data System (ADS)

    Kuc, Agnieszka; Seifert, Gotthard

    2006-12-01

    Carbon foams are hypothetical carbon allotropes that contain graphitelike ( sp2 carbon) segments, connected by sp3 carbon atoms, resulting in porous structures. In this work the density-functional-based tight-binding method with periodic boundary conditions was employed to study the energetics, the stability, and the electronic properties of this unusual class of carbon systems. Concerning the most stable phases of carbon (graphite and diamond), foams show high structural stability at very low mass density. The electronic band structure and electronic density of states of foams indicate a similar size dependence as for carbon nanotubes. The calculated bulk moduli are in the range between those of graphite (5.5GPa) and diamond (514GPa) . These structures may represent stable carbon modifications with sp2-sp3 hybridization. The low density and high porosity make the carbon foams interesting as materials for hydrogen storage, for example.

  16. Measurement of carbon capture efficiency and stored carbon leakage

    DOEpatents

    Keeling, Ralph F.; Dubey, Manvendra K.

    2013-01-29

    Data representative of a measured carbon dioxide (CO.sub.2) concentration and of a measured oxygen (O.sub.2) concentration at a measurement location can be used to determine whether the measured carbon dioxide concentration at the measurement location is elevated relative to a baseline carbon dioxide concentration due to escape of carbon dioxide from a source associated with a carbon capture and storage process. Optionally, the data can be used to quantify a carbon dioxide concentration increase at the first location that is attributable to escape of carbon dioxide from the source and to calculate a rate of escape of carbon dioxide from the source by executing a model of gas-phase transport using at least the first carbon dioxide concentration increase. Related systems, methods, and articles of manufacture are also described.

  17. Microbially mediated carbon mineralization: Geoengineering a carbon-neutral mine

    NASA Astrophysics Data System (ADS)

    Power, I. M.; McCutcheon, J.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2013-12-01

    Ultramafic and mafic mine tailings are a potentially valuable feedstock for carbon mineralization, affording the mining industry an opportunity to completely offset their carbon emissions. Passive carbon mineralization has previously been documented at the abandoned Clinton Creek asbestos mine, and the active Diavik diamond mine and Mount Keith nickel mine, yet the majority of tailings remain unreacted. Examples of microbe-carbonate interactions at each mine suggest that biological pathways could be harnessed to promote carbon mineralization. In suitable environmental conditions, microbes can mediate geochemical processes to accelerate mineral dissolution, increase the supply of carbon dioxide (CO2), and induce carbonate precipitation, all of which may accelerate carbon mineralization. Tailings mineralogy and the availability of a CO2 point source are key considerations in designing tailings storage facilities (TSF) for optimizing carbon mineralization. We evaluate the efficacy of acceleration strategies including bioleaching, biologically induced carbonate precipitation, and heterotrophic oxidation of waste organics, as well as abiotic strategies including enhancing passive carbonation through modifying tailings management practices and use of CO2 point sources (Fig. 1). With the aim of developing carbon-neutral mines, implementation of carbon mineralization strategies into TSF design will be driven by economic incentives and public pressure for environmental sustainability in the mining industry. Figure 1. Schematic illustrating geoengineered scenarios for carbon mineralization of ultramafic mine tailings. Scenarios A and B are based on non-point and point sources of CO2, respectively.

  18. Terrestrial Carbon Cycle Variability.

    PubMed

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2, temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y (-1)) with respect to a large and uncertain background (123 +/- 4 Pg-C y (-1)), and

  19. Terrestrial Carbon Cycle Variability

    PubMed Central

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2, temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1), and

  20. Functionalization of carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Korneva, Guzeliya

    Carbon nanotubes have unique properties that make them attractive for different engineering applications. However, because of their chemical inertness, carbon nanotubes have to be functionalized in order to acquire additional physico-chemical properties. Large multiwalled carbon nanotubes are different from fullerenes and singlewalled nanotubes because the stresses in their walls are almost relaxed while most chemical methods for fullerene functionalization exploit this effect of stressed bonds. The objective of this work is to develop new methods for functionalization of multiwalled carbon nanotubes. This work is dedicated to study two functionalization methods. The first deals with physico-chemical functionalization by filling the nanotube interior with colloidal suspensions. Irreversible adsorption of functional nanoparticles on the nanotube wall leads to the nanotube functionalization. The second method is purely chemical functionalization, which uses the reaction of cyclopropanation to break pi-bonds in the benzene rings of the nanotubes with formation of new σ-bonds with deprotonated malonate. This so-called Bingel reaction has been used in fullerene chemistry and in this work was applied for the first time to functionalize multiwalled carbon nanotubes. While capillary filling of carbon nanotubes was known long ago, the research community was skeptical about possibility of engulfing nanoparticles into nanotubes by capillary forces. We developed and implemented capillary method to fill nanotubes with different nanoparticles. Using this method, magnetic carbon nanotubes were produced for the first time. Synthesized nanotubes have very high magnetic moment and allow to manipulate them by magnetic field. These magnetic nanotubes have been successfully used in fabrication of carbon nanotube-tipped pipettes for biological probes. The Bingel reaction was studied on three sets of multiwalled carbon nanotubes with diameters: 20nm, 100nm, and 300nm. To estimate the

  1. Fluorescent carbon 'quantum' dots from thermochemical functionalization of carbon nanoparticles

    NASA Astrophysics Data System (ADS)

    Rednic, Monica I.; Lu, Zhuomin; Wang, Ping; LeCroy, Gregory E.; Yang, Fan; Liu, Yun; Qian, Haijun; Terec, Anamaria; Veca, L. Monica; Lu, Fushen; Sun, Ya-Ping

    2015-10-01

    Fluorescent carbon 'quantum' dots are generally obtained by deliberate chemical functionalization of carbon nanoparticles or by 'one-pot' carbonization processing. For brightly fluorescent carbon dots with optoelectronic polymers, a hybrid approach was developed to use pre-processed and selected carbon nanoparticles as precursor for surface passivation by poly(9-vinylcarbazole) (PVK) in one-pot thermochemical processing, thus taking advantage of the more controllable feature from the deliberate functionalization and also the versatility associated with the one-pot synthesis. The PVK-carbon dots were characterized by optical spectroscopy, microscopy, and other techniques. The broad applicability of the hybrid approach is discussed.

  2. Response of carbon-carbon composites to challenging environments

    NASA Technical Reports Server (NTRS)

    Maahs, Howard G.; Ohlhorst, Craig W.; Barrett, David M.; Ransone, Philip O.; Sawyer, J. Wayne

    1988-01-01

    This paper presents results from material performance evaluations of oxidation-resistant carbon-carbon composites intended for multiuse aerospace applications, which cover the effects of the following environmental parameters: the oxidizing nature of the environments (including both high and low oxygen partial pressures), high temperatures, moisture, cyclic temperature service, and foreign-object impact. Results are presented for the carbon-carbon material currently in use as the thermal-protection-system material on Space Shuttle, as well as for newer and more advanced structural forms of carbon-carbon composites.

  3. Carbon fuel particles used in direct carbon conversion fuel cells

    DOEpatents

    Cooper, John F [Oakland, CA; Cherepy, Nerine [Oakland, CA

    2012-01-24

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  4. Carbon Fuel Particles Used in Direct Carbon Conversion Fuel Cells

    DOEpatents

    Cooper, John F.; Cherepy, Nerine

    2008-10-21

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  5. Carbon fuel particles used in direct carbon conversion fuel cells

    DOEpatents

    Cooper, John F.; Cherepy, Nerine

    2012-10-09

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  6. Carbon fuel particles used in direct carbon conversion fuel cells

    DOEpatents

    Cooper, John F.; Cherepy, Nerine

    2011-08-16

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  7. Chemically modified carbonic anhydrases useful in carbon capture systems

    DOEpatents

    Novick, Scott J; Alvizo, Oscar

    2013-10-29

    The present disclosure relates to chemically modified carbonic anhydrase polypeptides and soluble compositions, homogenous liquid formulations comprising them. The chemically modified carbonic anhydrase polypeptides have improved properties relative to the same carbonic anhydrase polypeptide that is not chemically modified including the improved properties of increased activity and/or stability in the presence of amine compounds, ammonia, or carbonate ion. The present disclosure also provides methods of preparing the chemically modified polypeptides and methods of using the chemically modified polypeptides for accelerating the absorption of carbon dioxide from a gas stream into a solution as well as for the release of the absorbed carbon dioxide for further treatment and/or sequestering.

  8. Chemically modified carbonic anhydrases useful in carbon capture systems

    DOEpatents

    Novick, Scott; Alvizo, Oscar

    2013-01-15

    The present disclosure relates to chemically modified carbonic anhydrase polypeptides and soluble compositions, homogenous liquid formulations comprising them. The chemically modified carbonic anhydrase polypeptides have improved properties relative to the same carbonic anhydrase polypeptide that is not chemically modified including the improved properties of increased activity and/or stability in the presence of amine compounds, ammonia, or carbonate ion. The present disclosure also provides methods of preparing the chemically modified polypeptides and methods of using the chemically modified polypeptides for accelerating the absorption of carbon dioxide from a gas stream into a solution as well as for the release of the absorbed carbon dioxide for further treatment and/or sequestering.

  9. Big Sky Carbon Atlas

    DOE Data Explorer

    The Big Sky Carbon Atlas is an online geoportal designed for you to discover, interpret, and access geospatial data and maps relevant to decision support and education on carbon sequestration in the Big Sky Region. In serving as the public face of the Partnership's spatial Data Libraries, the Atlas provides a gateway to geographic information characterizing CO2 sources, potential geologic sinks, terrestrial carbon fluxes, civil and energy infrastructure, energy use, and related themes. In addition to directly serving the BSCSP and its stakeholders, the Atlas feeds regional data to the NatCarb Portal, contributing to a national perspective on carbon sequestration. Established components of the Atlas include a gallery of thematic maps and an interactive map that allows you to: • Navigate and explore regional characterization data through a user-friendly interface • Print your map views or publish them as PDFs • Identify technical references relevant to specific areas of interest • Calculate straight-line or pipeline-constrained distances from point sources of CO2 to potential geologic sink features • Download regional data layers (feature under development) (Acknowledgment to the Big Sky Carbon Sequestration Partnership (BSCSP); see home page at http://www.bigskyco2.org/)

  10. Dynamics of seawater carbonate chemistry, production, and calcification of a coral reef flat, central Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Albright, R.; Langdon, C.; Anthony, K. R. N.

    2013-10-01

    Ocean acidification is projected to shift coral reefs from a state of net accretion to one of net dissolution this century. Presently, our ability to predict global-scale changes to coral reef calcification is limited by insufficient data relating seawater carbonate chemistry parameters to in situ rates of reef calcification. Here, we investigate diel and seasonal trends in carbonate chemistry of the Davies Reef flat in the central Great Barrier Reef and relate these trends to benthic carbon fluxes by quantifying net ecosystem calcification (nec) and net community production (ncp). Results show that seawater carbonate chemistry of the Davies Reef flat is highly variable over both diel and seasonal cycles. pH (total scale) ranged from 7.92 to 8.17, pCO2 ranged from 272 to 542 μatm, and aragonite saturation state (Ωarag) ranged from 2.9 to 4.1. Diel cycles in carbonate chemistry were primarily driven by ncp, and warming explained 35% and 47% of the seasonal shifts in pCO2 and pH, respectively. Daytime ncp averaged 37 ± 19 mmol C m-2 h-1 in summer and 33 ± 13 mmol C m-2 h-1 in winter; nighttime ncp averaged -30 ± 25 and -7 ± 6 mmol C m-2 h-1 in summer and winter, respectively. Daytime nec averaged 11 ± 4 mmol CaCO3 m-2 h-1 in summer and 8 ± 3 mmol CaCO3 m-2 h-1 in winter, whereas nighttime nec averaged 2 ± 4 mmol and -1 ± 3 mmol CaCO3 m-2 h-1 in summer and winter, respectively. Net ecosystem calcification was highly sensitive to changes in Ωarag for both seasons, indicating that relatively small shifts in Ωarag may drive measurable shifts in calcification rates, and hence carbon budgets, of coral reefs throughout the year.

  11. Polymeric Carbon Dioxide

    SciTech Connect

    Yoo, C-S.

    1999-11-02

    Synthesis of polymeric carbon dioxide has long been of interest to many chemists and materials scientists. Very recently we discovered the polymeric phase of carbon dioxide (called CO{sub 2}-V) at high pressures and temperatures. Our optical and x-ray results indicate that CO{sub 2}-V is optically non-linear, generating the second harmonic of Nd: YLF laser at 527 nm and is also likely superhard similar to cubic-boron nitride or diamond. CO{sub 2}-V is made of CO{sub 4} tetrahedra, analogous to SiO{sub 2} polymorphs, and is quenchable at ambient temperature at pressures above 1 GPa. In this paper, we describe the pressure-induced polymerization of carbon dioxide together with the stability, structure, and mechanical and optical properties of polymeric CO{sub 2}-V. We also present some implications of polymeric CO{sub 2} for high-pressure chemistry and new materials synthesis.

  12. Orbiting Carbon Observatory

    NASA Technical Reports Server (NTRS)

    Miller, Charles E.

    2005-01-01

    Human impact on the environment has produced measurable changes in the geological record since the late 1700s. Anthropogenic emissions of CO2 today may cause the global climate to depart for its natural behavior for many millenia. CO2 is the primary anthropogenic driver of climate change. The Orbiting Carbon Observatory goals are to help collect measurements of atmospheric CO2, answering questions such as why the atmospheric CO2 buildup varies annually, the roles of the oceans and land ecosystems in absorbing CO2, the roles of North American and Eurasian sinks and how these carbon sinks respond to climate change. The present carbon cycle, CO2 variability, and climate uncertainties due atmospheric CO2 uncertainties are highlighted in this presentation.

  13. Carbon-particle generator

    DOEpatents

    Hunt, A.J.

    1982-09-29

    A method and apparatus whereby small carbon particles are made by pyrolysis of a mixture of acetylene carried in argon. The mixture is injected through a nozzle into a heated tube. A small amount of air is added to the mixture. In order to prevent carbon build-up at the nozzle, the nozzle tip is externally cooled. The tube is also elongated sufficiently to assure efficient pyrolysis at the desired flow rates. A key feature of the method is that the acetylene and argon, for example, are premixed in a dilute ratio, and such mixture is injected while cool to minimize the agglomeration of the particles, which produces carbon particles with desired optical properties for use as a solar radiant heat absorber.

  14. HOLLOW CARBON ARC DISCHARGE

    DOEpatents

    Luce, J.S.

    1960-10-11

    A device is described for producing an energetic, direct current, hollow, carbon-arc discharge in an evacuated container and within a strong magnetic field. Such discharges are particularly useful not only in dissociation and ionization of high energy molecular ion beams, but also in acting as a shield or barrier against the instreaming of lowenergy neutral particles into a plasma formed within the hollow discharge when it is used as a dissociating mechanism for forming the plasma. There is maintained a predetermined ratio of gas particles to carbon particles released from the arc electrodes during operation of the discharge. The carbon particles absorb some of the gas particles and are pumped along and by the discharge out of the device, with the result that smaller diffusion pumps are required than would otherwise be necessary to dispose of the excess gas.

  15. Carbon neutral hydrocarbons.

    PubMed

    Zeman, Frank S; Keith, David W

    2008-11-13

    Reducing greenhouse gas emissions from the transportation sector may be the most difficult aspect of climate change mitigation. We suggest that carbon neutral hydrocarbons (CNHCs) offer an alternative pathway for deep emission cuts that complement the use of decarbonized energy carriers. Such fuels are synthesized from atmospheric carbon dioxide (CO2) and carbon neutral hydrogen. The result is a liquid fuel compatible with the existing transportation infrastructure and therefore capable of a gradual deployment with minimum supply disruption. Capturing the atmospheric CO2 can be accomplished using biomass or industrial methods referred to as air capture. The viability of biomass fuels is strongly dependent on the environmental impacts of biomass production. Strong constraints on land use may favour the use of air capture. We conclude that CNHCs may be a viable alternative to hydrogen or conventional biofuels and warrant a comparable level of research effort and support.

  16. Tensile Strength of Carbon/Carbon Composites

    NASA Astrophysics Data System (ADS)

    Hatta, Hiroshi; Aoi, Tatsuji; Kawahara, Itaru; Kogo, Yasuo; Shiota, Ichiro

    In order to identify ruling mechanisms of tensile fracture of Carbon/Carbon composites (C/Cs), tensile tests were carried out for various C/Cs as functions of the density, heat treatment temperature, and interfacial strength between fiber and matrix. Three processing routes of preformed yarn, resin char, and HIP processes were adopted to densify C/Cs. These C/Cs were finally heat-treated at temperatures from 2273K to 3300K. The interfacial strength between fiber and matrix was varied by the selection of processing routes. As a result, two ruling failure mechanisms were identified. At density lower than 1.6g/cm3, the tensile fracture was controlled by stress transfer capability from the matrix to reinforcing fibers. However, at higher density than 1.6g/cm3, tensile strength was primarily governed by the interfacial strength between the matrix and fibers. Thus the latter mechanism is nearly same as ceramic matrix composites.

  17. Superconductivity in carbon nanomaterials

    NASA Astrophysics Data System (ADS)

    Dlugon, Katarzyna

    The purpose of this thesis is to explain the phenomenon of superconductivity in carbon nanomaterials such as graphene, fullerenes and carbon nanotubes. In the introductory chapter, there is a description of superconductivity and how it occurs at critical temperature (Tc) that is characteristic and different to every superconducting material. The discovery of superconductivity in mercury in 1911 by Dutch physicist Heike Kamerlingh Onnes is also mentioned. Different types of superconductors, type I and type II, low and high temperatures superconductors, as well as the BCS theory that was developed in 1957 by Bardeen, Cooper, and Schrieffer, are also described in detail. The BCS theory explains how Cooper's pairs are formed and how they are responsible for the superconducting properties of many materials. The following chapters explain superconductivity in doped fullerenes, graphene and carbon nanotubes, respectively. There is a thorough explanation followed by many examples of different types of carbon nanomaterials in which small changes in chemical structure cause significant changes in superconducting properties. The goal of this research was not only to take into consideration well known carbon based superconductors but also to search for the newest available materials such as the fullerene nanowhiskers discovered quite recently. There is also a presentation of fairly new ideas about inducing superconductivity in a monolayer of graphene which is more challenging than inducing superconductivity in graphite by simply intercalating metal atoms between its graphene sheets. An effort has been taken to look for any available information about carbon nanomaterials that have the potential to superconduct at room temperature, mainly because discovery of such materials would be a real revolution in the modern world, although no such materials have been discovered yet.

  18. Solid State Carbon Monoxide Sensor

    NASA Technical Reports Server (NTRS)

    Upchurch, Billy T. (Inventor); Wood, George M. (Inventor); Schryer, David R. (Inventor); Leighty, Bradley D. (Inventor); Oglesby, Donald M. (Inventor); Kielin, Erik J. (Inventor); Brown, Kenneth G. (Inventor); DAmbrosia, Christine M. (Inventor)

    1999-01-01

    A means for detecting carbon monoxide which utilizes an un-heated catalytic material to oxidize carbon monoxide at ambient temperatures. Because this reaction is exothermic, a thermistor in contact with the catalytic material is used as a sensing element to detect the heat evolved as carbon monoxide is oxidized to carbon dioxide at the catalyst surface, without any heaters or external heating elements for the ambient air or catalytic element material. Upon comparison to a reference thermistor, relative increases in the temperature of the sensing thermistor correspond positively with an increased concentration of carbon monoxide in the ambient medium and are thus used as an indicator of the presence of carbon monoxide.

  19. Inkjet Printing of Carbon Nanotubes

    PubMed Central

    Tortorich, Ryan P.; Choi, Jin-Woo

    2013-01-01

    In an attempt to give a brief introduction to carbon nanotube inkjet printing, this review paper discusses the issues that come along with preparing and printing carbon nanotube ink. Carbon nanotube inkjet printing is relatively new, but it has great potential for broad applications in flexible and printable electronics, transparent electrodes, electronic sensors, and so on due to its low cost and the extraordinary properties of carbon nanotubes. In addition to the formulation of carbon nanotube ink and its printing technologies, recent progress and achievements of carbon nanotube inkjet printing are reviewed in detail with brief discussion on the future outlook of the technology.

  20. Pitch carbon microsphere composite

    NASA Technical Reports Server (NTRS)

    Price, H. L.; Nelson, J. B.

    1977-01-01

    Petroleum pitch carbon microspheres were prepared by flash heating emulsified pitch and carbonizing the resulting microspheres in an inert atmosphere. Microsphere composites were obtained from a mixture of microspheres and tetraester precursor pyrrone powder. Scanning electron micrographs of the composite showed that it was an aggregate of microspheres bonded together by the pyrrone at the sphere contact points, with voids in and among the microspheres. Physical, thermal, and sorption properties of the composite are described. Composite applications could include use as a honeycomb filler in elevated-temperature load-bearing sandwich boards or in patient-treatment tables for radiation treatment of tumors.

  1. Carbon wastewater treatment process

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

    1974-01-01

    A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

  2. Carbon Capture and Storage

    SciTech Connect

    Friedmann, S

    2007-10-03

    Carbon capture and sequestration (CCS) is the long-term isolation of carbon dioxide from the atmosphere through physical, chemical, biological, or engineered processes. This includes a range of approaches including soil carbon sequestration (e.g., through no-till farming), terrestrial biomass sequestration (e.g., through planting forests), direct ocean injection of CO{sub 2} either onto the deep seafloor or into the intermediate depths, injection into deep geological formations, or even direct conversion of CO{sub 2} to carbonate minerals. Some of these approaches are considered geoengineering (see the appropriate chapter herein). All are considered in the 2005 special report by the Intergovernmental Panel on Climate Change (IPCC 2005). Of the range of options available, geological carbon sequestration (GCS) appears to be the most actionable and economic option for major greenhouse gas reduction in the next 10-30 years. The basis for this interest includes several factors: (1) The potential capacities are large based on initial estimates. Formal estimates for global storage potential vary substantially, but are likely to be between 800 and 3300 Gt of C (3000 and 10,000 Gt of CO{sub 2}), with significant capacity located reasonably near large point sources of the CO{sub 2}. (2) GCS can begin operations with demonstrated technology. Carbon dioxide has been separated from large point sources for nearly 100 years, and has been injected underground for over 30 years (below). (3) Testing of GCS at intermediate scale is feasible. In the US, Canada, and many industrial countries, large CO{sub 2} sources like power plants and refineries lie near prospective storage sites. These plants could be retrofit today and injection begun (while bearing in mind scientific uncertainties and unknowns). Indeed, some have, and three projects described here provide a great deal of information on the operational needs and field implementation of CCS. Part of this interest comes from several

  3. Ultrahard carbon nanocomposite films

    SciTech Connect

    SIEGAL,MICHAEL P.; TALLANT,DAVID R.; PROVENCIO,PAULA P.; OVERMYER,DONALD L.; SIMPSON,REGINA L.; MARTINEZ-MIRANDA,L.J.

    2000-01-27

    Modest thermal annealing to 600 C of diamondlike amorphous-carbon (a-C) films grown at room temperature results in the formation of carbon nanocomposites with hardness similar to diamond. These nanocomposite films consist of nanometer-sized regions of high density a-C embedded in an a-C matrix with a reduced density of 5--10%. The authors report on the evolution of density and bonding topologies as a function of annealing temperature. Despite a decrease in density, film hardness actually increases {approximately} 15% due to the development of the nanocomposite structure.

  4. Nanomechanics of carbon nanotubes.

    PubMed

    Kis, Andras; Zettl, Alex

    2008-05-13

    Some of the most important potential applications of carbon nanotubes are related to their mechanical properties. Stiff sp2 bonds result in a Young's modulus close to that of diamond, while the relatively weak van der Waals interaction between the graphitic shells acts as a form of lubrication. Previous characterization of the mechanical properties of nanotubes includes a rich variety of experiments involving mechanical deformation of nanotubes using scanning probe microscopes. These results have led to promising prototypes of nanoelectromechanical devices such as high-performance nanomotors, switches and oscillators based on carbon nanotubes.

  5. Blue Carbon distribution in mangrove forests of the Americas

    NASA Astrophysics Data System (ADS)

    Simard, M.; Rivera-Monroy, V.; Fatoyinbo, T. E.; Roy Chowdhury, R.

    2013-12-01

    Globally, coastal ecosystems are critical to maintaining human livelihood and biodiversity. These ecosystems including mangroves, salt marshes, and sea grasses provide essential ecosystem services, such as supporting fisheries by providing important spawning grounds, filtering pollutants and contaminants from coastal waters, and protecting coastal development and communities against storms, floods and erosion. Additionally, recent research indicates that these vegetated coastal ecosystems are highly efficient carbon sinks (i.e. 'Blue Carbon') and can potentially play a significant role in ameliorating the effect of increasing global climate change by capturing significant amounts of carbon into sediments and plant biomass. The term blue carbon indicates the carbon stored in coastal vegetated wetlands (i.e., mangroves, intertidal marshes, and seagrass meadows). As a result of rapid global changes in coastal regions, it is crucial that we improve our understanding of the current and future state of the remaining coastal ecosystems and associated ecosystem services and their vulnerability to global climate change. In this study, we present a continental scale study of mangrove distribution and assess patterns of forest structural development associated to latitude and geomorphological setting. We produced a baseline map of mangrove canopy height and biomass for all mangrove forests of the Americas using data from the Shuttle Radar Topography Mission (SRTM) and publicly available land cover maps (Figure 1). The resulting canopy height map was calibrated using ICEsat/Geoscience Laser Altimeter system (GLAS). Biomass was derived from field data and allometry. The maps were validated with field data and results in accuracies that vary spatially around 2 to 3m in height and 20% in biomass. Figure 1: Global distribution of mangrove forests (green) and SRTM elevation data. These data were used to produce large scale maps of mangrove canopy height and biomass.

  6. Carbon tips for all-carbon single-molecule electronics.

    PubMed

    Dappe, Y J; González, C; Cuevas, J C

    2014-06-21

    We present here an exhaustive ab initio study of the use of carbon-based tips as electrodes in single-molecule junctions. Motivated by recent experiments, we show that carbon tips can be combined with other carbon nanostructures, such as graphene, to form all-carbon molecular junctions with molecules like benzene or C60. Our results show that the use of carbon tips can lead to relatively conductive molecular junctions. However, contrary to junctions formed with standard metals, the conductance traces recorded during the formation of the all-carbon single-molecule junctions do not exhibit clear conductance plateaus, which can be attributed to the inability of the hydrogenated carbon tips to form chemical bonds with the organic molecules. Additionally, we explore here the use of carbon tips for scanning tunneling microscopy and show that they are well suited for obtaining sample images with atomic resolution.

  7. Development of carbon-carbon composites from solvent extracted pitch

    SciTech Connect

    1996-06-24

    There are several methods used to fabricate carbon-carbon composites. One used extensively in the fabrication of aerospace components such as rocket nozzles and reentry vehicle nosetips, as well as commercial components for furnace fixturing and glass manufacturing, is the densification of a woven preform with molten pitch, and the subsequent conversion of the pitch to graphite through heat treatment. Two types of pitch are used in this process; coal tar pitch and petroleum pitch. The objective of this program was to determine if a pitch produced by the direct extraction of coal could be used as a substitute for these pitches in the fabrication of carbon-carbon composites. The program involved comparing solvent extracted pitch with currently accepted pitches and rigidizing a carbon-carbon preform with solvent extracted pitch for comparison with carbon-carbon fabricated with currently available pitch.

  8. Surface modification of carbon fuels for direct carbon fuel cells

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Zhu, Zhonghua; Chen, Jiuling; De Marco, Roland; Dicks, Andrew; Bradley, John; Lu, Gaoqing

    The direct carbon fuel cell (DCFC) is a promising power-generation device that has much higher efficiency (80%) and less emissions than conventional coal-fired power plants. Two commercial carbons (activated carbon and carbon black) pre-treated with HNO 3, HCl or air plasma are tested in a DCFC. The correlation between the surface properties and electrochemical performance of the carbon fuels is explored. The HNO 3-treated carbon fuels have the highest electrochemical reactivity in the DCFC due to the largest degree of surface oxygen functional groups. The overall effect on changing the electrochemical reactivity of carbon fuels is in the order HNO 3 > air plasma ≈ HCl. Product gas analysis indicates that complete oxidation of carbon to CO 2 can be achieved at 600-700 °C.

  9. Single-walled carbon nanotube buckypaper and mesophase pitch carbon/carbon composites

    NASA Astrophysics Data System (ADS)

    Park, Jin Gyu; Yun, Nam Gyun; Park, Young Bin; Liang, Richard; Lumata, Lloyd; Brooks, James; Zhang, Chuck; Wang, Ben; High-Performance Materials Institute, Fsu Collaboration; National High Magnetic Field Laboratory, Fsu Collaboration

    2011-03-01

    Carbon/carbon composites consisting of single-walled carbon nanotube (SWCNT) buckypaper (BP) and mesophase pitch resin have been produced through impregnation of BP with pitch using toluene as a solvent. Drying, stabilization and carbonization processes were performed sequentially, and repeated to increase the pitch content. Voids in the carbon/carbon composite samples decreased with increasing impregnation process cycles. Electrical conductivity and density of the composites increased with carbonization by two to three times that of pristine BP. These results indicate that discontinuity and intertube contact barriers of SWCNTs in the BP are partially overcome by the carbonization process of pitch. The temperature dependence of the Raman shift shows that mechanical strain is increased since carbonized pitch matrix surrounds the nanotubes. High-Performance Materials Institute, NSF DMR-0602859, NSF DMR-0654118.

  10. Method for production of carbon nanofiber mat or carbon paper

    DOEpatents

    Naskar, Amit K.

    2015-08-04

    Method for the preparation of a non-woven mat or paper made of carbon fibers, the method comprising carbonizing a non-woven mat or paper preform (precursor) comprised of a plurality of bonded sulfonated polyolefin fibers to produce said non-woven mat or paper made of carbon fibers. The preforms and resulting non-woven mat or paper made of carbon fiber, as well as articles and devices containing them, and methods for their use, are also described.

  11. Measuring black carbon spectral extinction in the visible and infrared

    NASA Astrophysics Data System (ADS)

    Smith, A. J. A.; Peters, D. M.; McPheat, R.; Lukanihins, S.; Grainger, R. G.

    2015-09-01

    This work presents measurements of the spectral extinction of black carbon aerosol from 400 nm to 15 μm. The aerosol was generated using a Miniature Combustion Aerosol Standard soot generator and then allowed to circulate in an aerosol cell where its extinction was measured using a grating spectrometer in the visible and a Fourier transform spectrometer in the infrared. Size distribution, number concentration, and mass extinction cross sections have also been obtained using single-particle aerosol samplers. A mean mass extinction cross section at 550 nm of 8.3 ± 1.6 m2 g-1 is found which, assuming a reasonable single scatter albedo of 0.2, corresponds to a mass absorption cross section of 6.6 ± 1.3 m2 g-1. This compares well with previously reported literature values. Computer analysis of electron microscope images of the particles provides independent confirmation of the size distribution as well as fractal parameters of the black carbon aerosol. The aerosol properties presented in this work are representative of very fresh, uncoated black carbon aerosol. After atmospheric processing of such aerosols (which could include mixing with other constituents and structural changes), different optical properties would be expected.

  12. High-level ab initio predictions of the energetics of mCO2·(H2O)n (n = 1-3, m = 1-12) clusters.

    PubMed

    Thanthiriwatte, K Sahan; Duke, Jessica R; Jackson, Virgil E; Felmy, Andrew R; Dixon, David A

    2012-10-04

    Electronic structure calculations at the correlated molecular orbital theory and density functional theory levels have been used to generate a reliable set of clustering energies for up to three water molecules in carbon dioxide clusters up to n = 12. The structures and energetics are dominated by Lewis acid-base interactions with hydrogen-bonding interactions playing a lesser energetic role. The actual binding energies are somewhat larger than might be expected. The correlated molecular orbital MP2 method and density functional theory with the ωB97X exchange-correlation functional provide good results for the energetics of the clusters, but the B3LYP and ωB97X-D functionals do not. Seven CO(2) molecules form the first solvent shell about a single H(2)O with four CO(2) molecules interacting with the H(2)O via Lewis acid-base interactions, two CO(2) interacting with the H(2)O by hydrogen bonds, and the seventh CO(2) completing the shell. The Lewis acid-base and weak hydrogen bond interactions between the water molecules and the CO(2) molecules are strong enough to disrupt the trimer ring configuration for as few as seven CO(2) molecules. Calculated (13)C NMR chemical shifts for mCO(2)·(H(2)O)(n) show little change with respect to the number of H(2)O or CO(2) molecules in the cluster. The O-H stretching frequencies do exhibit shifts that can provide information about the interactions between water and CO(2) molecules.

  13. High Level ab initio Predictions of the Energetics of mCO2•(H2O)n (n = 1-3, m = 1-12) Clusters

    SciTech Connect

    Thanthiriwatte, Sahan; Duke, Jessica R.; Jackson, Virgil E.; Felmy, Andrew R.; Dixon, David A.

    2012-10-04

    Electronic structure calculations at the correlated molecular orbital theory and density functional theory levels have been used to generate a reliable set of clustering energies for up to three water molecules in carbon dioxide clusters up to n = 12. The structures and energetics are dominated by Lewis acid-base interactions with hydrogen bonding interactions playing a lesser energetic role. The actual binding energies are somewhat larger than might be expected. The correlated molecular orbital MP2 method and density functional theory with the ωB97X exchange-correlation functional provide good results for the energetics of the clusters but the B3LYP and ωB97X-D functionals do not. Seven CO2 molecules form the first solvent shell about a single H2O with four CO2 molecules interacting with the H2O via Lewis acid-base interactions, two CO2 interacting with the H2O by hydrogen bonds, and the seventh CO2 completing the shell. The Lewis acid-base and weak hydrogen bond interactions between the water molecules and the CO2 molecules are strong enough to disrupt the trimer ring configuration for as few as seven CO2 molecules. Calculated 13C NMR chemical shifts for mCO2•(H2O)n show little change with respect to the number of H2O or CO2 molecules in the cluster. The O-H stretching frequencies do exhibit shifts that can provide information about the interactions between water and CO2 molecules.

  14. Method of Manufacturing Carbon Fiber Reinforced Carbon Composite Valves

    NASA Technical Reports Server (NTRS)

    Rivers, H. Kevin (Inventor); Ransone, Philip O. (Inventor); Northam, G. Burton (Inventor)

    1998-01-01

    A method for forming a carbon composite valve for internal combustion engines is discussed. The process includes the steps of braiding carbon fiber into a rope thereby forming a cylindrically shaped valve stem portion and continuing to braid said fiber while introducing into the braiding carbon fiber rope a carbon matrix plug having an outer surface in a net shape of a valve head thereby forming a valve head portion. The said carbon matrix plug acting as a mandrel over which said carbon fiber rope is braided, said carbon fiber rope and carbon matrix plug forming a valve head portion suitable for mating with a valve seat; cutting said braided carbon valve stem portion at one end to form a valve tip and cutting said braided carbon fiber after said valve head portion to form a valve face and thus provide a composite valve preform; and densifying said preform by embedding the braided carbon in a matrix of carbon to convert said valve stem portion to a valve stem and said valve head portion to a valve head thereby providing said composite valve.

  15. Australian carbon dust emission: a carbon accounting omission?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Erosion preferentially removes the finest carbon- and nutrient-rich soil fractions, and consequently its role may be significant within terrestrial carbon (C) cycles. However, the impacts of wind erosion on soil organic carbon redistribution are not considered in most SOC models, or within the Austr...

  16. Some Observations on Stress Graphitization in Carbon-Carbon Composites

    DTIC Science & Technology

    1992-09-15

    expansion ( CTE ) versus heat-treatment temperature for T-50/PAA carbon-carbon com posites...are derived from asphaltic precursors such as coal -tar and petroleum pitches. These materials are unique in passing through a liquid-crystalline...at a lower tem- perature and, for a given temperature, proceeded more extensively in the hard carbon than in a graphitizing polyvinylchloride coke

  17. Determination of carbonate carbon in geological materials by coulometric titration

    USGS Publications Warehouse

    Engleman, E.E.; Jackson, L.L.; Norton, D.R.

    1985-01-01

    A coulometric titration is used for the determination of carbonate carbon in geological materials. Carbon dioxide is evolved from the sample by the addition of 2 M perchloric acid, with heating, and is determined by automated coulometric titration. The coulometric titration showed improved speed and precision with comparable accuracy to gravimetric and gasometric techniques. ?? 1985.

  18. Transmissivity of carbon monoxide

    NASA Technical Reports Server (NTRS)

    Drayson, S. R.; Tallamraju, R.; Chaney, L. W.

    1973-01-01

    The line strengths and self- and nitrogen-broadened half widths for selected lines of the 4.6 micron fundamental band of carbon monoxide were determined. The band strength determined at stp. is higher than previously reported measurements. The half widths agree well with other measurements and calculations.

  19. Carbon-Fuelled Future

    SciTech Connect

    Appel, Aaron M.

    2014-09-12

    Whether due to changes in policy or consumption of available fossil fuels, alternative sources of energy will be required, especially given the rising global energy demand. However, one of the main factors limiting the widespread utilization of renewable energy, such as wind, solar, wave or geothermal, is our ability to store energy. Storage of energy from carbon-neutral sources, such as electricity from solar or wind, can be accomplished through many routes. One approach is to store energy in the form of chemical bonds, as fuels. The conversion of low-energy compounds, such as water and carbon dioxide, to higher energy molecules, such as hydrogen or carbon-based fuels, enables the storage of carbon-neutral energy on a very large scale. The author¹s work in this area is supported by the US Department of Energy Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory is operated by Battelle for the US Department of Energy.

  20. Geoengineering and Carbon Management

    NASA Astrophysics Data System (ADS)

    Marland, G.

    2002-05-01

    The term "geoengineering" was coined by Cesare Marchetti in the 1970's to describe a project that proposed to inject CO2 from electric generating plants into the deep ocean. The term has since been used to discuss a variety of projects that would involve purposeful, large-scale manipulation of the environment---primarily projects with the intent of mitigating anthropogenic changes in climate. Many activities that we now discuss under the title of "carbon management" have been previously identified as geoengineering. The term geoengineering is also used to describe possibilities for engineering the Earth's climate through large-scale manipulation of the energy balance, for example through manipulating the Earth's albedo. Studies are now showing more clearly that these two components, once treated separately under broad heading of "geoengineering", are linked. That is, for example, managing carbon through protecting or planting forests is also to manage the Earth's surface albedo and surface energy balance. Likewise, manipulating the albedo will alter the global carbon cycle. In this paper we discuss the evolution of the idea of geoengineering, summarizing the history of these technologies, and demonstrating how geoengineering includes, links, and melds with carbon management.

  1. Carbon Materials Research

    DTIC Science & Technology

    2005-07-14

    behavior, interfacial energies, and surface molecular orientation (surface anchoring states) for mesophase pitch on carbon fibers and other...Mochida (2) extended it to the production of mesophase pitch by dramatically raising Distribution A: Approved for public release; distribution...involved i.e. it is a very insoluble material. Mochida, however, recognized that this material was liquid-crystalline mesophase pitch , which was

  2. Carbon cloth supported electrode

    DOEpatents

    Lu, Wen-Tong P.; Ammon, Robert L.

    1982-01-01

    A flow-by anode is disclosed made by preparing a liquid suspension of about to about 18% by weight solids, the solids comprising about 3.5 to about 8% of a powdered catalyst of platinum, palladium, palladium oxide, or mixtures thereof; about 60 to about 76% carbon powder (support) having a particle size less than about 20 m.mu.m and about 20 to about 33% of an inert binder having a particle size of less than about 500 m.mu.m. A sufficient amount of the suspension is poured over a carbon cloth to form a layer of solids about 0.01 to about 0.05 cm thick on the carbon cloth when the electrode is completed. A vacuum was applied to the opposite side of the carbon cloth to remove the liquid and the catalyst layer/cloth assembly is dried and compressed at about 10 to about 50 MPa's. The binder is then sintered in an inert atmosphere to complete the electrode. The electrode is used for the oxidation of sulfur dioxide in a sulfur based hybrid cycle for the decomposition of water.

  3. Carbon nanotube solar cells.

    PubMed

    Klinger, Colin; Patel, Yogeshwari; Postma, Henk W Ch

    2012-01-01

    We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

  4. Polyimide/carbon Nanocomposites

    NASA Technical Reports Server (NTRS)

    Harris, Frank W.

    2003-01-01

    The goal of this product is to design and characterize well-defined conductive nanocomposite materials. The materials will be composed of a polymer matrix composed of rigid-backbone polyimides, and will be filled with modified or unmodified multi-walled carbon nanotubes (MWNTs). The ultimate design of this project is to create composite materials with optical clarity and a high conductivity.

  5. Carbon smackdown: wind warriors

    SciTech Connect

    Glen Dahlbacka of the Accelerator & Fusion Research Division and Ryan Wiser of the Environmental Energy Technologies Division are the speakers.

    2010-07-21

    July 16. 2010 carbon smackdown summer lecture: learn how Berkeley Lab scientists are developing wind turbines to be used in an urban setting, as well as analyzing what it will take to increase the adoption of wind energy in the U.S.

  6. Carbon smackdown: wind warriors

    ScienceCinema

    Glen Dahlbacka of the Accelerator & Fusion Research Division and Ryan Wiser of the Environmental Energy Technologies Division are the speakers.

    2016-07-12

    July 16. 2010 carbon smackdown summer lecture: learn how Berkeley Lab scientists are developing wind turbines to be used in an urban setting, as well as analyzing what it will take to increase the adoption of wind energy in the U.S.

  7. Bench Remarks: Carbon Dioxide.

    ERIC Educational Resources Information Center

    Bent, Henry A.

    1987-01-01

    Discusses the properties of carbon dioxide in its solid "dry ice" stage. Suggests several demonstrations and experiments that use dry ice to illustrate Avogadro's Law, Boyle's Law, Kinetic-Molecular Theory, and the effects of dry ice in basic solution, in limewater, and in acetone. (TW)

  8. Carbon nanotubes for microelectronics?

    PubMed

    Graham, Andrew P; Duesberg, Georg S; Seidel, Robert V; Liebau, Maik; Unger, Eugen; Pamler, Werner; Kreupl, Franz; Hoenlein, Wolfgang

    2005-04-01

    Despite all prophecies of its end, silicon-based microelectronics still follows Moore's Law and continues to develop rapidly. However, the inherent physical limits will eventually be reached. Carbon nanotubes offer the potential for further miniaturization as long as it is possible to selectively deposit them with defined properties.

  9. Dewatering Peat With Activated Carbon

    NASA Technical Reports Server (NTRS)

    Rohatgi, N. K.

    1984-01-01

    Proposed process produces enough gas and carbon to sustain itself. In proposed process peat slurry is dewatered to approximately 40 percent moisture content by mixing slurry with activated carbon and filtering with solid/liquid separation techniques.

  10. Carbon Monoxide (CO) Poisoning Prevention

    MedlinePlus

    ... What's this? Submit Button Past Emails CDC Features Carbon Monoxide (CO) Poisoning Prevention Language: English Español (Spanish) ... tornadoes), using alternative sources of power can cause carbon monoxide (CO) to build up in a home ...

  11. Atmospheric Entry of Carbonate Micrometeoroids

    NASA Astrophysics Data System (ADS)

    Micca Longo, G.; Longo, S.

    2017-02-01

    Micrometeoroids have similarities in chemistry and mineralogy to the CI, CM, and CR chondrites. A first study of carbonate micrometeoroids atmospheric entry is performed. A thermal decomposition model of initially pure magnesium carbonate is proposed.

  12. Bioenergy, the Carbon Cycle, and Carbon Policy

    NASA Astrophysics Data System (ADS)

    Kammen, D. M.

    2003-12-01

    The evolving energy and land-use policies across North America and Africa provide critical case studies in the relationship between regional development, the management of natural resources, and the carbon cycle. Over 50 EJ of the roughly 430 EJ total global anthropogenic energy budget is currently utilized in the form of direct biomass combustion. In North America 3 - 4 percent of total energy is derived from biomass, largely in combined heat and power (CHP) combustion applications. By contrast Africa, which is a major consumer of 'traditional' forms of biomass, uses far more total bioenergy products, but largely in smaller batches, with quantities of 0.5 - 2 tons/capita at the household level. Several African nations rely on biomass for well over 90 percent of household energy, and in some nations major portions of the industrial energy supply is also derived from biomass. In much of sub-Saharan Africa the direct combustion of biomass in rural areas is exceeded by the conversion of wood to charcoal for transport to the cities for household use there. There are major health, and environmental repercussions of these energy flows. The African, as well as Latin American and Asian charcoal trade has a noticeable signature on the global greenhouse gas cycles. In North America, and notably Scandinavia and India as well, biomass energy and emerging conversion technologies are being actively researched, and provide tremendous opportunities for the evolution of a sustainable, locally based, energy economy for many nations. This talk will examine aspects of these current energy and carbon flows, and the potential that gassification and new silvicultural practices hold for clean energy systems in the 21st century. North America and Africa will be examined in particular as both sources of innovation in this field, and areas with specific promise for application of these energy technologies and biomass/land use practices to further energy and global climate management.

  13. Where is mantle's carbon?

    NASA Astrophysics Data System (ADS)

    Oganov, A. R.; Ono, S.; Ma, Y.

    2008-12-01

    Due to the strongly reducing conditions (the presence of metallic iron was suggested both by experiments [1] and theory [2]), diamond was believed to be the main host of carbon through most of the lower mantle [3]. We showed [4] that cementite Fe3C is another good candidate to be the main host of "reduced" carbon in the mantle, reinforcing an earlier hypothesis [5]. The fate of "oxidised" carbon (in subducted slabs) is of particular importance - if carbonates decompose producing fluid CO2, this would have important implications for the chemistry and rheology of the mantle. Knowledge of crystal structures and phase diagrams of carbonates is crucial here. The high-pressure structures of CaCO3 were predicted [6] and subsequently verified by experiments. For MgCO3, Isshiki et al. [7] found a new phase above 110 GPa, and several attempts were made to solve it [8,9]. Here [4], using an evolutionary algorithm for crystal structure prediction [10], we show that there are two post-magnesite phases at mantle-relevant pressure range, one stable at 82-138 GPa, and the other from 138 GPa to ~160 GPa. Both are based on threefold rings of CO4-tetrahedra and are more favourable than all previously proposed structures. We show that through most of the P-T conditions of the mantle, MgCO3 is the major host of oxidized carbon in the Earth. We predict the possibility of CO2 release at the very bottom of the mantle (in SiO2-rich basaltic part of subducted slabs), which could enhance partial melting of rocks and be related to the geodynamical differences between the Earth and Venus. 1.Frost D.J., Liebske C., Langenhorst F., McCammon C.A., Tronnes R.G., Rubie D.C. (2004). Experimental evidence for the existence of iron-rich metal in the Earth's lower mantle. Nature 428, 409-412. 2.Zhang F., Oganov A.R. (2006). Valence and spin states of iron impurities in mantle-forming silicates. Earth Planet. Sci. Lett. 249, 436-443. 3.Luth R.W. (1999). Carbon and carbonates in the mantle. In: Mantle

  14. Design and syntheses of hybrid metal–organic materials based on K{sub 3}[M(C{sub 2}O{sub 4}){sub 3}]·3H{sub 2}O [M(III)=Fe, Al, Cr] metallotectons

    SciTech Connect

    Sun, Yayong; Zong, Yingxia; Ma, Haoran; Zhang, Ao; Liu, Kang; Wang, Debao Wang, Wenqiang; Wang, Lei

    2016-05-15

    By using K{sub 3}[M(C{sub 2}O{sub 4}){sub 3}]·3H{sub 2}O [M(III)=Fe, Al, Cr] (C{sub 2}O{sub 4}{sup 2−}=oxalate) metallotectons as the starting material, we have synthesized eight novel complexes with formulas [{Fe(C_2O_4)_2(H_2O)_2}{sub 2}]·(H–L{sub 1}){sub 2}·H{sub 2}O 1, [Fe(C{sub 2}O{sub 4})Cl{sub 2}]·(H{sub 2}–L{sub 2}){sub 0.5}·(L{sub 2}){sub 0.5}·H{sub 2}O 2, [{Fe(C_2O_4)_1_._5Cl_2}{sub 2}]·(H–L{sub 3}){sub 4}3, [Fe{sub 2}(C{sub 2}O{sub 4})Cl{sub 8}]·(H{sub 2}–L{sub 4}){sub 2}·2H{sub 2}O 4, K[Al(C{sub 2}O{sub 4}){sub 3}]·(H{sub 2}–L{sub 5})·2H{sub 2}O 5, K[Al(C{sub 2}O{sub 4}){sub 3}]·(H–L{sub 6}){sub 2}·2H{sub 2}O 6, K[Cr(C{sub 2}O{sub 4}){sub 3}]·2H{sub 2}O 7, Na[Fe(C{sub 2}O{sub 4}){sub 3}]·(H–L{sub 6}){sub 2}·2H{sub 2}O 8 (with L{sub 1}=4-dimethylaminopyridine, L{sub 2}=2,3,5,6-tetramethylpyrazine, L{sub 3}=2-aminobenzimidazole, L{sub 4}=1,4-bis-(1H-imidazol-1-yl)benzene, L{sub 5}=1,4-bis((2-methylimidazol-1-yl)methyl)benzene, L{sub 6}=2-methylbenzimidazole). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra and thermogravimetric analyses. Compound 3 is a 2D H-bonded supramolecular architecture. Others are 3D supramolecular structures. Compound 1 shows a [Fe(C{sub 2}O{sub 4}){sub 2}(H{sub 2}O){sub 2}]{sup −} unit and 3D antionic H-bonded framework. Compound 2 features a [Fe(C{sub 2}O{sub 4})Cl{sub 2}]{sup -} anion and 1D iron-oxalate-iron chain. Compound 3 features a [Fe{sub 2}(C{sub 2}O{sub 4}){sub 3}Cl{sub 4}]{sup 4−} unit. Compound 4 features distinct [Fe{sub 2}(C{sub 2}O{sub 4})Cl{sub 8}]{sup 4−} units, which are mutual linked by water molecules to generated a 2D H-bonded network. Compound 5 features infinite ladder-like chains constructed by [Al(C{sub 2}O{sub 4}){sub 3}]{sup 3−} units and K{sup +} cations. The 1D chains are further extended into 3D antionic H-bonded framework through O–H···O H-bonds. Compounds 6–8 show 2D [KAl(C{sub 2}O

  15. Templated Growth of Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Siochik Emilie J. (Inventor)

    2007-01-01

    A method of growing carbon nanotubes uses a synthesized mesoporous si lica template with approximately cylindrical pores being formed there in. The surfaces of the pores are coated with a carbon nanotube precu rsor, and the template with the surfaces of the pores so-coated is th en heated until the carbon nanotube precursor in each pore is convert ed to a carbon nanotube.

  16. Carbon nanotube array based sensor

    DOEpatents

    Lee, Christopher L.; Noy, Aleksandr; Swierkowski, Stephan P.; Fisher, Karl A.; Woods, Bruce W.

    2005-09-20

    A sensor system comprising a first electrode with an array of carbon nanotubes and a second electrode. The first electrode with an array of carbon nanotubes and the second electrode are positioned to produce an air gap between the first electrode with an array of carbon nanotubes and the second electrode. A measuring device is provided for sensing changes in electrical capacitance between the first electrode with an array of carbon nanotubes and the second electrode.

  17. Porous carbon EOS: numerical analysis

    NASA Astrophysics Data System (ADS)

    Aliverdiev, A.; Batani, D.; Dezulian, R.; Vinci, T.

    2010-10-01

    In this paper, we address the problem of direct simulation of laser-driven shock experiments aiming at determining the equation of state (EOS) of carbon using the "relative" impedance mismatch method. In particular, using tabulated carbon EOS (SESAME library, material number 7830), we have found some difficulties in reducing the initial density of the material in simulations with porous carbon. We have therefore calculated a new EOS for porous carbon with a reduced bulk modulus.

  18. Poly(carbonate-imide) polymer

    NASA Technical Reports Server (NTRS)

    St. Clair, Terry L. (Inventor); Maudgal, Shubha (Inventor); Pratt, J. Richard (Inventor)

    1987-01-01

    A novel series of polymers and copolymers based on a polyimide backbone with the incorporation of carbonate moieties along the backbone. The process for preparing these polymers and copolymers is also disclosed as is a novel series of dinitrodiphenyl carbonates and diaminodiphenyl carbonates. The novel polymers and copolymers exhibit high temperature capability and because of the carbonate unit, many exhibit a high degree of order and/or crystallinity.

  19. Poly (Carbonate-Mide) Polymer

    NASA Technical Reports Server (NTRS)

    St.clair, T. L. (Inventor); Maudgal, S. (Inventor); Pratt, J. R. (Inventor)

    1986-01-01

    A novel series of polymers and copolymers based on a polymide backbone with the incorporation of carbonate moieties along the backbone is presented. The preparation process for the polymers and copolymers is disclosed together with a novel series of dinitrodiphenyl carbonates and diaminodiphenyl carbonates. The novel polyners and copolymers exhibit high temperature capability and because of the carbonate unit, many exhibit a high degree of order and/or crystallinity.

  20. Advancing Climate and Carbon Simulation

    SciTech Connect

    Thompson, S

    2004-12-14

    We use a recently developed integrated climate/carbon model to perform breakthrough studies of the climate. Two major studies are carried out--namely the effects of CO{sub 2}-fertilized vegetation on global climate and carbon dynamics, and the effect of climate sensitivity on carbon cycle feedback. We have also begun development of a next-generation climate/carbon modeling capability.