Science.gov

Sample records for ja carbon expo

  1. IT Expo

    NASA Image and Video Library

    2012-06-21

    Jaci Mize of the National Oceanic and Atmospheric Administration at Stennis Space Center learns about 'phishing,' a favorite ploy used by hackers to gain sensitive information from unsuspecting computer users, during the eighth annual Information Technology Expo held June 2, 2012,1 at the rocket engine test facility.

  2. Innovation Expo

    NASA Image and Video Library

    2016-11-03

    Representatives from Parker Brothers, known for designing and building outrageous custom vehicles, spoke to employees at NASA's Kennedy Space Center in Florida about their creative thinking processes. The event took place during the center's 2016 Innovation Expo. Employees also were given an up-close look at their Neutron bike, featured in the movie “Tron.”

  3. Innovation Expo

    NASA Image and Video Library

    2016-11-03

    During the 2016 Innovation Expo at NASA's Kennedy Space Center in Florida, representatives from Parker Brothers, known for designing and building outrageous custom vehicles, spoke to Kennedy employees about their creative thinking processes. Employees also were given an up-close look at their Neutron bike, featured in the movie “Tron.”

  4. Past Project Expo Sites

    EPA Pesticide Factsheets

    This page provides information for Project Expo sites that were featured at the LMOP Conferences in 2013 and 2014. Project Expo sites were featured as being interested in identifying project partners for the development of an LFG energy project.

  5. 2011 IT Expo

    NASA Image and Video Library

    2011-06-21

    Stennis Space Center employees enjoyed an opportunity to learn about available and emerging information technology services during the seventh annual IT Expo in the Roy S. Estess Building on June 21. The expo featured exhibits on a variety of services and capabilities, including applications support, IT security, video production, audiovisual services and records management.

  6. Custom Career Expos.

    ERIC Educational Resources Information Center

    Barnard, Tracie

    2001-01-01

    At Florida State University, the career placement staff tailors its career expos to the needs of students and employers. This article discusses how they market their expos; their online recruiter registration; how they recruit volunteers; and the importance of hospitality. (Author/MKA)

  7. A Revamped Science Expo

    ERIC Educational Resources Information Center

    Barth, Lorna

    2007-01-01

    By changing the venue from festival to a required academic exposition, the traditional science fair was transformed into a "Science Expo" wherein students were guided away from cookbook experiments toward developing a question about their environment into a testable and measurable experiment. The revamped "Science Expo" became a night for students…

  8. A Revamped Science Expo

    ERIC Educational Resources Information Center

    Barth, Lorna

    2007-01-01

    By changing the venue from festival to a required academic exposition, the traditional science fair was transformed into a "Science Expo" wherein students were guided away from cookbook experiments toward developing a question about their environment into a testable and measurable experiment. The revamped "Science Expo" became a night for students…

  9. 2011 Technology Expo

    NASA Image and Video Library

    2011-05-26

    Phillip Stallcup with Agilent Technologies in Huntsville, Ala., talks with NASA employees Leslie Ladner (l) and Kelly Sullivan about spectrum analyzers and other test equipment during the Stennis Technology Expo on May 26. The expo was hosted by NASA Solutions for Enterprise-Wide Procurement and featured various exhibitors demonstrating the latest in a range of technologies, such as training equipment, secure data storage, video networks, distance learning and data management.

  10. EPA ExpoBox

    EPA Pesticide Factsheets

    EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases, mode

  11. Exploration and Sustainability Expo Welcome

    NASA Image and Video Library

    NASA Ames Deputy Associate Director Dr. Yvonne Pendleton welcomes attendees to the 2009 Exploration and Sustainability Expo held at NASA Ames Research Center. She highlights the emerging technologi...

  12. Stennis holds Information Technology Expo

    NASA Image and Video Library

    2010-06-16

    Brian Wagner (l to r) with the U.S. Navy, Andrew Hiukenbein with NVision Solutions and Theresa Avoskey with the Naval Oceanographic Office at Stennis Space Center learn about the latest improvements in making flash drives secure during an Information Technology Expo held June 16. Various area companies visited Stennis during the day to offer exhibits for employees on a range of information technology topics. The theme of the daylong expo was 'The Road to Green IT Computing.'

  13. Innovation Expo with Bob Cabana

    NASA Image and Video Library

    2016-11-02

    Kennedy Space Center Director Bob Cabana stops by a NASA booth in the Space Station Processing Facility conference center during the 2016 Innovation Expo. Now in its fifth year, the purpose of the Innovation Expo is to help foster innovation and creativity among Kennedy employees who are encouraged to look for ways to do their work better and to propose concepts for tackling future mission needs.

  14. Innovation Expo with Bob Cabana

    NASA Image and Video Library

    2016-11-02

    Visitors stop by a NASA booth in the Space Station Processing Facility conference center at NASA's Kennedy Space Center during the 2016 Innovation Expo. Now in its fifth year, the purpose of the Innovation Expo is to help foster innovation and creativity among Kennedy employees who are encouraged to look for ways to do their work better and to propose concepts for tackling future mission needs.

  15. Innovation Expo with Bob Cabana

    NASA Image and Video Library

    2016-11-02

    A visitor checks out a virtual reality device at a NASA booth in the Space Station Processing Facility conference center during NASA's Kennedy Space Center during the 2016 Innovation Expo. Now in its fifth year, the purpose of the Innovation Expo is to help foster innovation and creativity among Kennedy employees who are encouraged to look for ways to do their work better and to propose concepts for tackling future mission needs.

  16. Innovation Expo with Bob Cabana

    NASA Image and Video Library

    2016-11-02

    Visitors were recently given an opportunity to stop by a NASA booth in the Space Station Processing Facility conference center at NASA's Kennedy Space Center during the 2016 Innovation Expo. Now in its fifth year, the purpose of the Innovation Expo is to help foster innovation and creativity among Kennedy employees who are encouraged to look for ways to do their work better and to propose concepts for tackling future mission needs.

  17. EPA Holds National Sustainable Design Expo

    EPA Pesticide Factsheets

    WASHINGTON, DC - Environmental Protection Agency (EPA) Deputy Administrator Stan Meiburg will open the 11th Annual National Sustainable Design Expo Saturday morning in Alexandria, Va. The expo will host student teams from colleges and universities across t

  18. Expo-Box Contact Us

    EPA Pesticide Factsheets

    EPA-Expo-Box is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases, mode

  19. EPA-Expo-Box Terminology

    EPA Pesticide Factsheets

    EPA-Expo-Box is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases,

  20. Engineered Porous Materials EXPO `93

    SciTech Connect

    Not Available

    1993-11-01

    The EXPO was organized to increase communication between US industry and DOE`s national laboratories. The report contains copies of viewgraphs of all speakers and reports of workshops designed to identify priority needs of industry. A conference synopsis and set of recommendations to DOE are also included.

  1. EPA ExpoBox Toolbox Search

    EPA Pesticide Factsheets

    EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant assessment data bases,

  2. Carbon catabolite repression-independent and pH-dependent production of indoles by Rubrivivax benzoatilyticus JA2.

    PubMed

    Mujahid, Md; Sasikala, Ch; Ramana, Ch V

    2013-10-01

    Rubrivivax benzoatilyticus JA2 produces indole derivatives (indoles) from aniline, anthranilate or L-tryptophan. Glucose repressed indole production in R. benzoatilyticus JA2, while malate had no effect. Growth of R. benzoatilyticus JA2 on glucose resulted in decrease in culture pH (6.4) compared with malate (8.4). Growth of R. benzoatilyticus JA2 on sugar carbon sources decreased culture pH (6.4-6.6) and indole production. Further, culture pH of 6.4 repressed the indole production, and pH 8.4 promoted the production irrespective of carbon sources used for growth. Moreover, correlation between indole production and culture pH was observed, where acidic pH inhibited indole production, while alkaline pH promoted the production, suggesting the role of pH in indole production. Tryptophan-catabolizing enzyme activities are significantly high in malate-grown cultures (pH 8.4) compared with that of the glucose (pH 6.4)-grown cultures and corroborated well with indole production, indicating their role in indole production. These results confirm that indole production in R. benzoatilyticus JA2 is pH dependent rather than carbon catabolite repression.

  3. EPA ExpoBox Related Links

    EPA Pesticide Factsheets

    EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases,

  4. Expo-Box: Submit Tool Information

    EPA Pesticide Factsheets

    EPA-Expo-Box is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases, mode

  5. Total Risk Integrated Methodology (TRIM) - TRIM.Expo

    EPA Pesticide Factsheets

    The Exposure Event module of TRIM (TRIM.Expo), similar to most human exposure models, provides an analysis of the relationships between various chemical concentrations in the environment and exposure levels of humans.

  6. Selected Papers Presented at MODSIM World 2011 Conference and Expo

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E. (Compiler); Bullock, Leanna S. (Compiler)

    2012-01-01

    Selected papers from MODSIM World 2011 Conference & Expo are contained in this NASA Conference Publication (CP). MODSIM World 2011 was held in Virginia Beach, Virginia, October 11-14, 2011. The theme of the 2011 conference & expo was "Overcoming Critical Global Challenges with Modeling & Simulation". The conference program consisted of five technical tracks - Defense, Homeland Security & First Responders; Education; Health & Medicine; The Human Dimension; and Serious Games & Virtual Worlds.

  7. Frequently Asked Questions about EPA ExpoBox

    EPA Pesticide Factsheets

    EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases,

  8. WFIRST Extragalactic Potential Observations (EXPO) Science Investigation Team

    NASA Astrophysics Data System (ADS)

    Robertson, Brant

    The Wide-Field InfraRed Survey Telescope (WFIRST) holds tremendous promise as a space observatory for extragalactic astrophysics beyond cosmological surveys. The WFIRST Extragalactic Potential Observations (EXPO) Science Investigation Team will identify the most pressing and scientifically compelling Guest Investigator and Guest Observer projects with WFIRST to address a range of exciting outstanding issues in galaxy formation, from the epoch of reionization to galaxy-galaxy lensing, the discovery of exotic supernovae and luminous active galaxies, and charting the chemical evolution of galaxies. The identified EXPO GI projects will help maximize the scientific return of the WFIRST cosmological surveys, and supply innovative ideas and methods for archival research that leverages the WFIRST dataset. The EXPO team will also evaluate the science payoff of translating previous successful space telescope surveys to the era of WFIRST, helping us to realize the full power of WFIRST for extragalactic astronomy through the competed GO programs. The WFIRST-EXPO team consists of world-wide experts in designing and executing space-based extragalactic programs, multi-object spectroscopic campaigns in the optical and infrared, and theoretical modeling of galaxy formation, exotic supernovae, and reionization. In support of WFIRST before Critical Design Review, WFIRST-EXPO will 1) develop and publicly release tools to generate mock catalogs for planning extragalactic astrophysics investigations with the HLS (GI) and GO community programs, 2) simulate images for modeling medium- and ultra-deep extragalactic GO programs, 3) develop and publicly release work flows for planning and evaluating the science return of potential extragalactic GI/GO programs, 4) perform case studies of medium- and ultra-deep imaging and spectroscopic GO/GI programs, 5) evaluate WFIRST design choices that influence extragalactic science return, and 6) serve as liaisons to James Webb Space Telescope, Large

  9. Selected Papers Presented at MODSIM World 2009 Conference and Expo

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E. (Editor)

    2010-01-01

    Selected papers from MODSIM World 2009 Conference and Expo are contained in this NASA Conference Publication (CP). MODSIM World 2009 was held in Virginia Beach, Virginia, October 14-16, 2009, at the Virginia Beach Convention Center. The theme of the 2009 conference and expo was "21st Century Decision-Making: The Art of Modeling & Simulation." The 79 submitted papers were peer-reviewed and 64 were accepted for presentation at MODSIM World 2009. As a condition of acceptance, the first author was responsible for securing/obtaining all permissions associated with the general release and public availability of the paper. Further, the first authors also had to grant NASA the right to include their papers in the NASA CP. There are 53 papers in this NASA CP.

  10. 2007 U.S. Coast Guard Innovation Expo Volume 1

    DTIC Science & Technology

    2007-11-01

    Twelve under contract • First to be delivered March 08 Mission Effectiveness Project: (CG Yard) • 1 – 110’complete, 4 on going, 18 remaining • 2 – 210... to USCG missions • Possible joint UAS effort with other DHS agencies 12/7/2007Unclassified | USCG Innovation Expo | CG-9 | 31 October 2007 24 Thank... Satellite Relays Data Through CGDN + Data Backbone Direct To MISLE & CG COP Databases MISLE & CG COP Databases Updated for Operational Use Data

  11. Updates on EPA’s High-Throughput Exposure Forecast (ExpoCast) Research Project (CPCP)

    EPA Science Inventory

    Recent research advances by the ORD ExpoCast project (CSS Rapid Exposure and Dosimetry) are presented to the computational toxicology community in the context of prioritizing chemicals on a risk-basis using joint ExpoCast and ToxCast predictions. Recent publications by Wambaugh e...

  12. Analysis of Mode Choice Performance among Heterogeneous Tourists to Expo Shanghai 2010

    NASA Astrophysics Data System (ADS)

    Jiang, Shengchuan; Du, Yuchuan; Sun, Lijun

    Tourist is a conventional kind of commuters in the urban transport system. During some mega-events, such as Olympic Games or Expos, tourists would become the most important and sizable part of commuters in the host city. Expo 2010 Shanghai will attract 70 millions tourists during the whole 184 days duration. The large number of tourists expected to be carried, combined with the congested urban road network and limited parking spaces, will make it difficult for individual transport to be used during the Expo; as such, high rates of utilization of public transport will be necessary. Hence, exploring the trip mode choice behavior of Expo tourists is the keystone for traffic planning of Expo 2010 Shanghai, especially for the difference of heterogeneous tourists from various departure areas. A joint model system, in the form of associating clustering analysis and HL model, is developed in this paper to investigate the differences of trip mode choice behaviour among heterogeneous tourist groups. The clustering analysis method is used in this paper to distinguish the various types of Expo tourists for the choice sets are variable with the attributes of groups. Sorted by the attribute of departure area, tourists of Expo Shanghai could be divided into three kinds: local visitors, out-of-town one-day-trip visitor and out-of-town lodging visitors. The statistic parameters of three kind models constructed by this joint system show that this modeling method improves analytic precision effectively.

  13. Analysis of Exocyst-Positive Organelle (EXPO)-Mediated Unconventional Protein Secretion (UPS) in Plant Cells.

    PubMed

    Ding, Yu; Wang, Juan

    2017-01-01

    Unconventional protein secretion (UPS) together with conventional protein secretion (CPS) is responsible for protein secretion in plants. We have previously identified a novel UPS pathway in plants, which is mediated by exocyst-positive organelle-EXPO. Here, we describe detailed protocols to study UPS in plants by using Arabidopsis protoplasts or transgenic suspension cells, expressing the EXPO marker Exo70E2-XFP, as materials. Via drug and osmotic treatment plus secretion assay, we illustrate several major methods to analyze EXPO-mediated UPS in plant cells, which also supplys mining tools for similar study.

  14. Selected Papers and Presentations Presented at MODSIM World 2010 Conference and Expo. Part 1

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E. (Editor)

    2011-01-01

    MODSIM World 2010 was held in Hampton, Virginia, October 13-15, 2010. The theme of the 2010 conference & expo was "21st Century Decision-Making: The Art of Modeling& Simulation". The conference program consisted of seven technical tracks - Defense, Engineering and Science, Health & Medicine, Homeland Security & First Responders, The Human Dimension, K-20 STEM Education, and Serious Games & Virtual Worlds. Selected papers and presentations from MODSIM World 2010 Conference & Expo are contained in this NASA Conference Publication (CP). Section 8.0 of this CP contains papers from MODSIM World 2009 Conference & Expo that were unavailable at the time of publication of NASA/CP-2010-216205 Selected Papers Presented at MODSIM World 2009 Conference and Expo, March 2010.

  15. Selected Papers and Presentations Presented at MODSIM World 2010 Conference Expo. Part 2

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E. (Editor)

    2011-01-01

    MODSIM World 2010 was held in Hampton, Virginia, October 13-15, 2010. The theme of the 2010 conference & expo was "21st Century Decision-Making: The Art of Modeling& Simulation". The conference program consisted of seven technical tracks - Defense, Engineering and Science, Health & Medicine, Homeland Security & First Responders, The Human Dimension, K-20 STEM Education, and Serious Games & Virtual Worlds. Selected papers and presentations from MODSIM World 2010 Conference & Expo are contained in this NASA Conference Publication (CP). Section 8.0 of this CP contains papers from MODSIM World 2009 Conference & Expo that were unavailable at the time of publication of NASA/CP-2010-216205 Selected Papers Presented at MODSIM World 2009 Conference and Expo, March 2010.

  16. Expo '86, Vancouver: impact on British Columbia's Children's Hospital.

    PubMed Central

    Hlady, L J; Macnab, A J; Smith, D F; Wensley, D F

    1987-01-01

    Over 22 million visitors attended the 1986 world exposition in Vancouver, and this had a significant impact on the local pediatric facility. A total of 559 children visited the emergency department of British Columbia's Children's Hospital with injuries or illnesses resulting from the fair. Of these, 193 (34%) had come directly from the site. The children's ages ranged from 1 1/2 months to 18 years, 4 months (mean 6.99 years). Of the 559 children 31% were not covered by medical insurance. Twenty-four of the children were admitted to the hospital, and one died at the Expo site. Most of the illnesses were upper respiratory tract infections and gastroenteritis. The proportion of visits for trauma was 50%, compared with the yearly average of 25%. There was a 6% increase in the workload in the emergency department during the fair; the percentage was even higher during July and August, particularly after 1800 hours. Recommendations are made to aid with the planning of medical care for similar events. PMID:3676971

  17. Results from an evaluation of tobacco control policies at the 2010 Shanghai World Expo.

    PubMed

    Li, Xiang; Zheng, PinPin; Fu, Hua; Berg, Carla; Kegler, Michelle

    2013-09-01

    Large-scale international events such as World Expos and Olympic Games have the potential to strengthen smoke-free norms globally. The Shanghai 2010 World Expo was one of the first large-scale events to implement and evaluate the adoption of strict tobacco control policies. To evaluate implementation of tobacco control policies at the 2010 World Expo in Shanghai, China. This mixed methods evaluation was conducted from July to October 2010. Observations were conducted in all 155 pavilions and outdoor queuing areas, all 45 souvenir shops, a random sample of restaurants (51 of 119) and selected outdoor non-smoking areas in all sections of the Expo. In addition, intercept surveys were completed with 3022 visitors over a 4-month period. All pavilions and souvenir shops were smoke-free. Restaurants were smoke-free, with only 0.1% of customers observed smoking. Smoking was more common in outdoor non-smoking areas, but still relatively rare overall with only 4.5% of visitors observed smoking. Tobacco products were not sold or marketed in any public settings except for three pavilions that had special exemptions from the policy. Overall, 80.3% of visitors were aware of the smoke-free policy at the World Expo, 92.5% of visitors supported the policy and 97.1% of visitors were satisfied with the smoke-free environment. Tobacco control policies at the World Expo sites were generally well-enforced and accepted although compliance was not 100%, particularly in outdoor non-smoking areas.

  18. Results from an evaluation of tobacco control policies at the 2010 Shanghai World Expo

    PubMed Central

    Li, Xiang; Zheng, PinPin; Fu, Hua; Berg, Carla; Kegler, Michelle

    2013-01-01

    Background Large-scale international events such as World Expos and Olympic Games have the potential to strengthen smoke-free norms globally. The Shanghai 2010 World Expo was one of the first large-scale events to implement and evaluate the adoption of strict tobacco control policies. Objective To evaluate implementation of tobacco control policies at the 2010 World Expo in Shanghai, China. Methods This mixed methods evaluation was conducted from July to October 2010. Observations were conducted in all 155 pavilions and outdoor queuing areas, all 45 souvenir shops, a random sample of restaurants (51 of 119) and selected outdoor non-smoking areas in all sections of the Expo. In addition, intercept surveys were completed with 3022 visitors over a 4-month period. Results All pavilions and souvenir shops were smoke-free. Restaurants were smoke-free, with only 0.1% of customers observed smoking. Smoking was more common in outdoor non-smoking areas, but still relatively rare overall with only 4.5% of visitors observed smoking. Tobacco products were not sold or marketed in any public settings except for three pavilions that had special exemptions from the policy. Overall, 80.3% of visitors were aware of the smoke-free policy at the World Expo, 92.5% of visitors supported the policy and 97.1% of visitors were satisfied with the smoke-free environment. Conclusions Tobacco control policies at the World Expo sites were generally well-enforced and accepted although compliance was not 100%, particularly in outdoor non-smoking areas. PMID:23708269

  19. Release of ToxCastDB and ExpoCastDB databases

    EPA Science Inventory

    EPA has released two databases - the Toxicity Forecaster database (ToxCastDB) and a database of chemical exposure studies (ExpoCastDB) - that scientists and the public can use to access chemical toxicity and exposure data. ToxCastDB users can search and download data from over 50...

  20. Science Students Creating Hybrid Spaces When Engaging in an Expo Investigation Project

    ERIC Educational Resources Information Center

    Ramnarain, Umesh; de Beer, Josef

    2013-01-01

    In this paper, we report on the experiences of three 9th-grade South African students (13-14 years) in doing open science investigation projects for a science expo. A particular focus of this study was the manner in which these students merge the world of school science with their social world to create a hybrid space by appropriating knowledge…

  1. The Student Biotechnology Expo: A New Model for a Science Fair.

    ERIC Educational Resources Information Center

    Chowning, Jeanne Ting

    2002-01-01

    Describes the first Student Biotechnology Expo which came about through the cooperation of high schools, universities, local biotechnology and biomedical companies, and research institutions with the purpose of providing opportunities to high school students to explore science related careers. (Contains 13 references.) (YDS)

  2. Science Students Creating Hybrid Spaces When Engaging in an Expo Investigation Project

    ERIC Educational Resources Information Center

    Ramnarain, Umesh; de Beer, Josef

    2013-01-01

    In this paper, we report on the experiences of three 9th-grade South African students (13-14 years) in doing open science investigation projects for a science expo. A particular focus of this study was the manner in which these students merge the world of school science with their social world to create a hybrid space by appropriating knowledge…

  3. Evaluation of a Sustainable Green Living Expo Event: Attendees' Reports of Satisfaction, Learning, and Behavior Change

    ERIC Educational Resources Information Center

    Diehl, David C.; Swenson, Shelley E.; Wente, Jessica N.

    2012-01-01

    This article presents the evaluation of the Sustainable Big Bend Green Living Expo and Education Fair, which targets participants with a variety of learning opportunities. Evaluation was carried out using onsite surveys along with follow-up surveys and phone interviews. Results indicate that a 1-day sustainability event is a meaningful way to…

  4. Release of ToxCastDB and ExpoCastDB databases

    EPA Science Inventory

    EPA has released two databases - the Toxicity Forecaster database (ToxCastDB) and a database of chemical exposure studies (ExpoCastDB) - that scientists and the public can use to access chemical toxicity and exposure data. ToxCastDB users can search and download data from over 50...

  5. A Model of the INEEL Science & Engineering Expo for Middle Schools

    ERIC Educational Resources Information Center

    Zounar, Elda

    2005-01-01

    Informal education can augment science classroom instruction and draw students to careers in science. The science and engineering expo, created by the Idaho National Engineering and Environmental Laboratory (INEEL), is a high-impact, inquiry-based, informal-education experience that can be replicated. It engages a broad range of students in…

  6. Processing and Characterization of Needled Carbon Composites

    DTIC Science & Technology

    2015-12-01

    ARL-RP-0563 ● DEC 2015 US Army Research Laboratory Processing and Characterization of Needled Carbon Composites by Bradley D...Lawrence, Travis A Bogetti, and Ryan P Emerson Reprinted from Proceedings of the 2015 Composites and Advanced Materials Expo (CAMX...US Army Research Laboratory Processing and Characterization of Needled Carbon Composites by Bradley D Lawrence TKC Global, LLC; Herndon, VA

  7. [The control of food hygiene during the world's fair in Seville (EXPO'92)].

    PubMed

    Durán Moreno, A; Moreno Durán, A; Toledano Hidalgo, P

    1993-01-01

    EXPO'92 has been one of the most important mass events held in Spain during several decades. Given the size of the event and the very complex circumstances surrounding the fair, the public health services had to face a big challenge. Food-hygiene and food-safety services, in particular were organized so as to take advantage and put into practice a fully managerial approach. Relevant conclusions can be drawn from such an experience which may be valuable not only with regards to similar mass-events in the future, but also for improving food hygiene in the overall Spanish context. In this article, the positive results obtained in the field of food hygiene and food safety at EXPO'92 are directly related by the authors with the methodology which was applied, namely the hazard analysis and critical control points. It is concluded that the interinstitutional coordination achieved played a decisive role.

  8. Surveillance of Mosquitoes and Selected Arthropod-Borne Viruses in the Context of Milan EXPO 2015

    PubMed Central

    Chiari, Mario; Calzolari, Mattia; Prosperi, Alice; Perulli, Simona; Faccin, Francesca; Avisani, Dominga; Cerioli, Monica; Zanoni, Mariagrazia; Tironi, Marco; Bertoletti, Marco; Defilippo, Francesco; Moreno, Ana; Farioli, Marco; Piatti, Alessandra; Dottori, Michele; Lelli, Davide; Lavazza, Antonio

    2016-01-01

    From 1 May 2015 to 31 October 2015 over 20 million visitors from all over the world visited the Universal Exhibition (EXPO) hosted by Milan (Lombardy region, Italy), raising concerns about the possible introduction of mosquito-borne diseases from endemic countries. The entomological surveillance protocol performed in Lombardy over the last three years was implemented in the EXPO area and in the two major regional airports using both Center for Disease Control CO2 and Biogents Sentinel traps. This surveillance aimed to estimate the presence and densities of putative vectors, and also to support investigations, including the vector species involved and area of diffusion, on the local spread of Chikungunya, Dengue and West Nile viruses (WNV) by competent vectors. From 3544 mosquitoes belonging to five different species, 28 pools of Culex spp. and 45 pools of Aedes spp. were screened for the presence of WNV, and for both Chikungunya and flaviviruses, respectively. The entomological surveillance highlighted a low density of potential vectors in the surveyed areas and did not reveal the presence of Chikungunya or Dengue viruses in the local competent vectors inside the EXPO area or in the two airports. In addition, the surveillance reported a low density of Culex spp. mosquitoes, which all tested negative for WNV. PMID:27399756

  9. The 7. global warming international conference and expo: Abstracts

    SciTech Connect

    1996-12-31

    This conference was held April 1--3, 1996 in Vienna, Austria. The purpose of this conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on global warming. Topics of interest include the following: global and regional natural resource management; energy, transportation, minerals and natural resource management; industrial technology and greenhouse gas emission; strategies for the mitigation of greenhouse gas emission; greenhouse gas production/utilization and carbon budgets; strategies for promoting the understanding of global change; international policy strategy and economics; and global warming and public health. Individual papers have been processed separately for inclusion in the appropriate data bases.

  10. Carbon and Oxygen Isotope Stratigraphy of the Ediacaran Jaíba Formation, Upper Bambuí Group, Brazil: Insights into Paleogeography and Sedimentary Environments after a Neoproterozoic Glaciation.

    NASA Astrophysics Data System (ADS)

    Caxito, F.; Uhlein, G. J.; Sial, A. N.; Uhlein, A.

    2015-12-01

    The Neoproterozoic Era was a time of extreme climatic variation as recorded in sedimentary rocks of this age across the globe, leading to a number of controversial hypotheses (e.g. the Snowball Earth glaciations). In eastern Brazil, the Bambuí Gr. is a thick carbonatic-siliciclastic unit that covers the São Francisco Craton and preserves remnants of a Neoproterozoic glaciation and their respective cap carbonate (1). Recent findings of Cloudina in the Januária region (2) suggest that at least part of the sequence might be upper Ediacaran or even Cambrian. Here we present the first carbon-oxygen isotope data for the Jaíba Fm., a ca. 50 m thick carbonate unit that occurs in the topmost portion of the Bambuí Gr. in this same region. The Jaíba Fm. post-dates the cap carbonate sequence and the fossil-bearing layers, and thus was probably deposited in the Ediacaran-Cambrian transition. Three stratigraphic columns were analyzed, and yielded similar ratios. Values of δ13CVPDB are between 0.8 and 3.4 ‰, while δ18OVPDB values are mostly around -8 ‰. These values contrasts with the negative δ13C values found for the base of the Bambuí Gr., followed by highly positive δ13C (up to +14‰) on its middle portion. The unusually high δ13C values are commonly interpreted as evidence for deposition on a restricted basin, such as in a foreland setting. The return to values which are close to the PDB standard in the uppermost Bambuí Gr. might thus indicate a change in the paleogeography and tectonic environment of the basin, suggesting an open, ventilated environment along with a recovery of the biological and hydrological cycle after a Late Neoproterozoic glaciation. Ongoing detailed sedimentological, geochemical and isotopic work might help to further clarify these issues and to provide new clues for unraveling Late Neoproterozoic paleoclimate, paleogeography and ocean chemistry. We thank FAPEMIG (Brazil) for finnacial support through grants n. APQ-00914-14 and PPM

  11. Space technology: A study of the significance of recognition for innovators of spinoff technologies. Commercial Space Expo-USA, 1993

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This is a report on the data collected at the Commercial Space Expo. The Expo was held 13-14 April 1993, in conjunction with the National Space Symposium. There were two modes of data gathering: surveys of expo registrants and exhibit feedback. In addition, exhibitors were interviewed to get their perspectives on the format of the expo and exhibits. Expo registrants were given a paper-pencil survey instrument at the beginning of the day and were asked to turn in the survey when they left for the day. Of the approximately 100 registrants, 22 surveys were returned. In the exhibit hall were five computers set up to collect people's reactions to specific exhibits. It was envisioned that people would react to each (or several) exhibits they visited. In fact, few people did this: almost everyone who visited a computer responded to one exhibit and did not stop by another computer. Therefore, we did not get a large number of responses for any particular exhibit. Nevertheless, there are some interesting data.

  12. Experimental Civilian Personnel Office Project (EXPO): Final Report for Appropriated Fund Sites

    DTIC Science & Technology

    1994-01-01

    service 3 Number of classification appeals CPO Number of clasification errors CPO I Managers’, supervisors’, and EXPO survey personnelists...complaints 4.12 -- 3.74 Production time lost 3.39 .3.61 -- Tune to cary out disciplinary actions 3.61 -- Problems 3.39 4.0) -- Number of discipline...1988 1989 1988 1989 1988 1989 n=177 n=136 n=129 n=85 n=145 n=79 The elimination of mandatory interviews ... 3 Is easy to cary out 6.13 6.37 5.41 5.98

  13. [Annual dynamics of cladocera community structure in Backshore Wetland of Expo Garden, Shanghai].

    PubMed

    Chen, Li-Jing; Wu, Yan-Fang; Jing, Yu-Xiang; Wang, Cong; Zhang, Yin-Jiang

    2012-10-01

    The Backshore Wetland of Expo Garden, Shanghai was one of the key parts of the World Expo construction project in 2010. From September 2009 to August 2010, a monthly investigation was conducted to understand the spatiotemporal dynamics of cladocera community structure (including species composition and standing crop) and related main affecting factors in the Backshore Wetland. A total of 36 cladocera species in 13 genera of 5 families were identified through the year. There were 12 dominant species, mainly Chydorus sphaericus, C. ovalis, Diaphanosoma leuchtenbergianum, and Sida crystalline. The mean annual abundance and biomass of the cladocera were 5.7 ind x L(-1) and 0.3559 mg x L(-1), respectively, and the annual dynamics of the standing crop showed bimodal, with the main peak in April and July, and the second peak in July and May, respectively. The Shannon index, Pielou index, and Margelf index were high in summer and autumn, but low in winter and spring. The canonical correspondence analysis (CCA) showed that water temperature, pH, dissolved oxygen, and nitrite nitrogen were the main factors affecting the community structure of cladocera in the Backshore Wetland.

  14. Event-Based Surveillance During EXPO Milan 2015: Rationale, Tools, Procedures, and Initial Results

    PubMed Central

    Manso, Martina Del; Caporali, Maria Grazia; Napoli, Christian; Linge, Jens P.; Mantica, Eleonora; Verile, Marco; Piatti, Alessandra; Pompa, Maria Grazia; Vellucci, Loredana; Costanzo, Virgilio; Bastiampillai, Anan Judina; Gabrielli, Eugenia; Gramegna, Maria; Declich, Silvia

    2016-01-01

    More than 21 million participants attended EXPO Milan from May to October 2015, making it one of the largest protracted mass gathering events in Europe. Given the expected national and international population movement and health security issues associated with this event, Italy fully implemented, for the first time, an event-based surveillance (EBS) system focusing on naturally occurring infectious diseases and the monitoring of biological agents with potential for intentional release. The system started its pilot phase in March 2015 and was fully operational between April and November 2015. In order to set the specific objectives of the EBS system, and its complementary role to indicator-based surveillance, we defined a list of priority diseases and conditions. This list was designed on the basis of the probability and possible public health impact of infectious disease transmission, existing statutory surveillance systems in place, and any surveillance enhancements during the mass gathering event. This article reports the methodology used to design the EBS system for EXPO Milan and the results of 8 months of surveillance. PMID:27314656

  15. Expo Outreach.

    ERIC Educational Resources Information Center

    Corlett, Cindy

    1998-01-01

    Describes a partnership between a middle school and an elementary school that pairs Grade Eight and Grade Two students. The middle school students have autonomy over the strategies and materials they use to teach a particular science lesson. Presents the details of implementing such a program. (DDR)

  16. MODSIM World 2007 Conference and Expo: Select Papers and Presentations from the Education and Training Track

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E. (Editor); Sullivan, Shannon (Editor); Sanchez, Alicia (Editor)

    2008-01-01

    This NASA Conference Publication features select papers and PowerPoint presentations from the Education and Training Track of MODSIM World 2007 Conference and Expo. Invited speakers and panelists of national and international renown, representing academia, industry and government, discussed how modeling and simulation (M&S) technology can be used to accelerate learning in the K-16 classroom, especially when using M&S technology as a tool for integrating science, technology, engineering and mathematics (STEM) classes. The presenters also addressed the application ofM&S technology to learning and training outside of the classroom. Specific sub-topics of the presentations included: learning theory; curriculum development; professional development; tools/user applications; implementation/infrastructure/issues; and workforce development. There was a session devoted to student M&S competitions in Virginia too, as well as a poster session.

  17. MODSIM World 2007 Conference and Expo: Select Papers and Presentations from the Education and Training Track

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E. (Editor); Sullivan, Shannon (Editor); Sanchez, Alicia (Editor)

    2008-01-01

    This NASA Conference Publication features select papers and PowerPoint presentations from the Education and Training Track of MODSIM World 2007 Conference and Expo. Invited speakers and panelists of national and international renown, representing academia, industry and government, discussed how modeling and simulation (M&S) technology can be used to accelerate learning in the K-16 classroom, especially when using M&S technology as a tool for integrating science, technology, engineering and mathematics (STEM) classes. The presenters also addressed the application ofM&S technology to learning and training outside of the classroom. Specific sub-topics of the presentations included: learning theory; curriculum development; professional development; tools/user applications; implementation/infrastructure/issues; and workforce development. There was a session devoted to student M&S competitions in Virginia too, as well as a poster session.

  18. Bibliographic description of photo database : The case study of "EXPO '90", The Photo Museum

    NASA Astrophysics Data System (ADS)

    Kamio, Tatsuo

    Advanced electronic technology enables to convert image information such as photos into the digital form and store the resulting data on to computers. Thus we have seen the movement toward constructing photo databases. One of the examples is the photo database exhibited at the Photo Museum of "EXPO '90" which will be held at Osaka in this coming April. Even image information database such as photos we have to still rely on languages when retrieving them. However, there exist different aspects from document information database so that we need to have much discussion on how to prepare guidelines or standards for bibliographic description of photo databases. Taking the Photo Museum as the case study this paper considers the photo databases. The bibliographic elements are categorized into four items; photographing behavior, photographing technique, title and subject. Particularly, subject category which can be searching keys, consists of sense information, subject class and keywords.

  19. [Response of copepod community characteristics to environmental factors in the Backshore Wetland of Expo Garden, Shanghai].

    PubMed

    Chen, Li-Jing; Wu, Yan-Fang; Jing, Yu-Xiang; Wang, Cong; Zhang, Yin-Jiang

    2012-11-01

    The Backshore Wetland of Expo Garden was the emphasis of the World Expo construction project in Shanghai in 2010, China programming district. We carried out studies on the community structure and spatial-temporal variation of copepod from September 2009 to August 2010. Statistical Product and Service Solutions (SPSS) was used for relevant statistical analysis between physicochemical parameters and copepod standing crop. Canonical correspondence analysis (CCA) was applied to further explore the correlation between copepod species and environmental parameters using CANOCO 4.5. A total of 23 copepod species in 11 genera, 6 families were identified. 5 dominant species of copepod were recorded during the survey period. They were Eucyclops serrulatus, Thermocyclops taihokuensis, Mesocyclops leuckarti, Thermocyclops brevifurcatus and Microcyclops varicans. The annual mean density of copepod was (8.6 +/- 16.6) ind x L(-1) and the biomass was (0.083 6 +/- 0.143 1) mg x L(-1). The standing crop of copepod had its first peak in July, the second in October and the bottom in January. The highest trophic level was measured at Site 1, decreasing along the flowing direction of the water current, and the lowest level was found at Site 10. The Margelf index remained low in winter and spring, but was increased in summer and autumn. The community structure of copepod was analyzed in relation to water quality parameters by canonical correspondence analysis (CCA). Water temperature, pH, nitrate nitrogen, nitrite nitrogen, TN, TP and dissolved oxygen were strongly correlated with the copepod community structure.

  20. Potential for MERLIN-Expo, an advanced tool for higher tier exposure assessment, within the EU chemical legislative frameworks.

    PubMed

    Suciu, Nicoleta; Tediosi, Alice; Ciffroy, Philippe; Altenpohl, Annette; Brochot, Céline; Verdonck, Frederik; Ferrari, Federico; Giubilato, Elisa; Capri, Ettore; Fait, Gabriella

    2016-08-15

    MERLIN-Expo merges and integrates advanced exposure assessment methodologies, allowing the building of complex scenarios involving several pollution sources and targets. The assessment of exposure and risks to human health from chemicals is of major concern for policy and ultimately benefits all citizens. The development and operational fusion of the advanced exposure assessment methodologies envisaged in the MERLIN-Expo tool will have a significant impact in the long term on several policies dealing with chemical safety management. There are more than 30 agencies in Europe related to exposure and risk evaluation of chemicals, which have an important role in implementing EU policies, having especially tasks of technical, scientific, operational and/or regulatory nature. The main purpose of the present paper is to introduce MERLIN-Expo and to highlight its potential for being effectively integrated within the group of tools available to assess the risk and exposure of chemicals for EU policy. The main results show that the tool is highly suitable for use in site-specific or local impact assessment, with minor modifications it can also be used for Plant Protection Products (PPPs), biocides and REACH, while major additions would be required for a comprehensive application in the field of consumer and worker exposure assessment. Copyright © 2016. Published by Elsevier B.V.

  1. Team Expo: A State-of-the-Art JSC Advanced Design Team

    NASA Technical Reports Server (NTRS)

    Tripathi, Abhishek

    2001-01-01

    In concert with the NASA-wide Intelligent Synthesis Environment Program, the Exploration Office at the Johnson Space Center has assembled an Advanced Design Team. The purpose of this team is two-fold. The first is to identify, use, and develop software applications, tools, and design processes that streamline and enhance a collaborative engineering environment. The second is to use this collaborative engineering environment to produce conceptual, system-level-of-detail designs in a relatively short turnaround time, using a standing team of systems and integration experts. This includes running rapid trade studies on varying mission architectures, as well as producing vehicle and/or subsystem designs. The standing core team is made up of experts from all of the relevant engineering divisions (e.g. Power, Thermal, Structures, etc.) as well as representatives from Risk and Safety, Mission Operations, and Crew Life Sciences among others. The Team works together during 2- hour sessions in the same specially enhanced room to ensure real-time integration/identification of cross-disciplinary issues and solutions. All subsystem designs are collectively reviewed and approved during these same sessions. In addition there is an Information sub-team that captures and formats all data and makes it accessible for use by the following day. The result is Team Expo: an Advanced Design Team that is leading the change from a philosophy of "over the fence" design to one of collaborative engineering that pushes the envelope to achieve the next-generation analysis and design environment.

  2. Influence of parameter values and variances and algorithm architecture in ConsExpo model on modeled exposures.

    PubMed

    Arnold, Susan F; Ramachandran, Gurumurthy

    2014-01-01

    This study evaluated the influence of parameter values and variances and model architecture on modeled exposures, and identified important data gaps that influence lack-of-knowledge-related uncertainty, using Consexpo 4.1 as an illustrative case study. Understanding the influential determinants in exposure estimates enables more informed and appropriate use of this model and the resulting exposure estimates. In exploring the influence of parameter placement in an algorithm and of the values and variances chosen to characterize the parameters within ConsExpo, "sensitive" and "important" parameters were identified: product amount, weight fraction, exposure duration, exposure time, and ventilation rate were deemed "important," or "always sensitive." With this awareness, exposure assessors can strategically focus on acquiring the most robust estimates for these parameters. ConsExpo relies predominantly on three algorithms to assess the default scenarios: inhalation vapors evaporation equation using the Langmuir mass transfer, the dermal instant application with diffusion through the skin, and the oral ingestion by direct uptake algorithm. These algorithms, which do not necessarily render health conservative estimates, account for 87, 89 and 59% of the inhalation, dermal and oral default scenario assessments,respectively, according them greater influence relative to the less frequently used algorithms. Default data provided in ConsExpo may be useful to initiate assessments, but are insufficient for determining exposure acceptability or setting policy, as parameters defined by highly uncertain values produce biased estimates that may not be health conservative. Furthermore, this lack-of-knowledge uncertainty makes the magnitude of this bias uncertain. Significant data gaps persist for product amount, exposure time, and exposure duration. These "important" parameters exert influence in requiring broad values and variances to account for their uncertainty. Prioritizing

  3. How to improve the air quality over mega-cities in China? - Pollution characterization and source analysis in Shanghai before, during, and after the 2010 World Expo

    NASA Astrophysics Data System (ADS)

    Huang, K.; Zhuang, G.; Lin, Y.; Wang, Q.; Fu, J. S.; Fu, Q.; Liu, T.; Deng, C.

    2013-02-01

    Three field campaigns were conducted before, during, and after the 2010 World Expo in Shanghai, aiming to understand the response of secondary aerosol components to both control measures and human activities. In spring, PM2.5 averaged 34.5 ± 20.9 μg m-3 with a severe pollution episode influenced by a floating dust originating from northwestern China on 26-28 April, right before the opening of the Expo. With the approaching of Expo, significant increasing trend of SNA (SO42-, NO3-, and NH4+) concentrations was observed from 20 April 20 to 2 May, attributing to the enhanced human activities. Nitrate had the most significant daily increasing rate of 1.1 μg m-3 d-1 due to enhanced vehicle emission. In summer, two intensive pollution episodes were found to be a mixed pollution of SNA with biomass burning due to loose control of post-harvest straw burning. Compared to the spring and summer of 2009, NO3- increased 12-15% while SO42- showed reductions of 15-30%. Continuous desulphurization of SO2 emission from power plants in recent years was responsible for the lowered SO42-, while enhanced traffic emission due to tremendous Expo visitors was the major contributor to the increased NO3-. In the autumn phase of the Expo before the closing of the Expo (20-30 October), the air quality over Shanghai was much better than ever before. However, the air quality rapidly plummeted as soon as the Expo was announced closed. SNA increased 3-6 folds to be 42.1 and 68.2 μg m-3 on 31 October and 1 November, respectively, as compared to 20-30 October. Of which, nitrate increased most with ~ 5-8 folds, indicating the serious impact from enhanced vehicle emission. The anthropogenic Ca as a tracer from construction dust increased from 2.88 ± 1.85 μg m-3 during the Expo to be 6.98 ± 3.19 μg m-3 during the post-Expo period, attributing to the resumption of construction works after the Expo. Compared to the autumn of 2009, all the ion components increased in 2010, owing to the lifting of

  4. How to improve the air quality over megacities in China: pollution characterization and source analysis in Shanghai before, during, and after the 2010 World Expo

    NASA Astrophysics Data System (ADS)

    Huang, K.; Zhuang, G.; Lin, Y.; Wang, Q.; Fu, J. S.; Fu, Q.; Liu, T.; Deng, C.

    2013-06-01

    Three field campaigns were conducted before, during, and after the 2010 World Expo in Shanghai, aiming to understand the response of secondary aerosol components to both control measures and human activities. In spring, PM2.5 (particulate matter) averaged 34.5 ± 20.9 μg m-3 with a severe pollution episode influenced by a floating dust originating from northwestern China on 26-28 April, right before the opening of the expo. With the approaching expo a significant increasing trend of SNA (SO42-, NO3-, and NH4+) concentrations was observed from 22 April to 2 May, attributed to the enhanced human activities. Nitrate had the most significant daily increasing rate of 1.1 μg m-3d-1 due to enhanced vehicle emission. In summer, two intensive pollution episodes were found to be a mixed pollution of SNA with biomass burning due to loose control of post-harvest straw burning. In the autumn phase of the expo, before the closing of the expo (20-30 October), the air quality over Shanghai was much better than ever before. However, the air quality rapidly plummeted as soon as the expo was announced closed. SNA increased 3-6 fold to be 42.1 and 68.2 μg m-3 on 31 October and 1 November, respectively, as compared to 20-30 October. Of which, nitrate increased most ~5-8 fold, indicating the serious impact from enhanced vehicle emission. Compared to the spring and summer of 2009, NO3- increased 12-15% while SO42- showed reductions of 15-30%. Continuous desulfurization of SO2 emission from power plants in recent years was responsible for the lowered SO42-, while increased traffic emission from the tremendous number of expo visitors was the major contributor to the increased NO3-. Compared to the autumn of 2009, all the ion components increased in 2010, owing to the lifting of emission control measures after the expo. SO42- was found least increased while NO3- and Ca2+ had tremendous increases of 150 and 320%, respectively. The anthropogenic Ca as a tracer from construction dust

  5. "We Cross Night": Some Reflections on the Role of the ESKOM Expo for Young Scientists as a Means of Accommodating Disadvantaged Learners into the Field of Science and Technology

    ERIC Educational Resources Information Center

    Alant, Busisiwe P.

    2010-01-01

    This article critiques the role of the ESKOM Expo for Young Scientists as a particularly salient node in the constitution of young learners' identity as prospective participants in the field of science and technology. The ESKOM Expo is seen as a particularly exciting means of providing access to the niche area of science and technology. Yet this…

  6. Modelling the exposure to chemicals for risk assessment: a comprehensive library of multimedia and PBPK models for integration, prediction, uncertainty and sensitivity analysis - the MERLIN-Expo tool.

    PubMed

    Ciffroy, P; Alfonso, B; Altenpohl, A; Banjac, Z; Bierkens, J; Brochot, C; Critto, A; De Wilde, T; Fait, G; Fierens, T; Garratt, J; Giubilato, E; Grange, E; Johansson, E; Radomyski, A; Reschwann, K; Suciu, N; Tanaka, T; Tediosi, A; Van Holderbeke, M; Verdonck, F

    2016-10-15

    MERLIN-Expo is a library of models that was developed in the frame of the FP7 EU project 4FUN in order to provide an integrated assessment tool for state-of-the-art exposure assessment for environment, biota and humans, allowing the detection of scientific uncertainties at each step of the exposure process. This paper describes the main features of the MERLIN-Expo tool. The main challenges in exposure modelling that MERLIN-Expo has tackled are: (i) the integration of multimedia (MM) models simulating the fate of chemicals in environmental media, and of physiologically based pharmacokinetic (PBPK) models simulating the fate of chemicals in human body. MERLIN-Expo thus allows the determination of internal effective chemical concentrations; (ii) the incorporation of a set of functionalities for uncertainty/sensitivity analysis, from screening to variance-based approaches. The availability of such tools for uncertainty and sensitivity analysis aimed to facilitate the incorporation of such issues in future decision making; (iii) the integration of human and wildlife biota targets with common fate modelling in the environment. MERLIN-Expo is composed of a library of fate models dedicated to non biological receptor media (surface waters, soils, outdoor air), biological media of concern for humans (several cultivated crops, mammals, milk, fish), as well as wildlife biota (primary producers in rivers, invertebrates, fish) and humans. These models can be linked together to create flexible scenarios relevant for both human and wildlife biota exposure. Standardized documentation for each model and training material were prepared to support an accurate use of the tool by end-users. One of the objectives of the 4FUN project was also to increase the confidence in the applicability of the MERLIN-Expo tool through targeted realistic case studies. In particular, we aimed at demonstrating the feasibility of building complex realistic exposure scenarios and the accuracy of the

  7. Assessing multimedia/multipathway exposures to inorganic arsenic at population and individual level using MERLIN-Expo.

    PubMed

    Van Holderbeke, Mirja; Fierens, Tine; Standaert, Arnout; Cornelis, Christa; Brochot, Céline; Ciffroy, Philippe; Johansson, Erik; Bierkens, Johan

    2016-10-15

    In this study, we report on model simulations performed using the newly developed exposure tool, MERLIN-Expo, in order to assess inorganic arsenic (iAs) exposure to adults resulting from past emissions by non-ferrous smelters in Belgium (Northern Campine area). Exposure scenarios were constructed to estimate external iAs exposure as well as the toxicologically relevant As (tAs, i.e., iAs, MMA and DMA) body burden in adults living in the vicinity of the former industrial sites as compared to adults living in adjacent areas and a reference area. Two scenarios are discussed: a first scenario studying exposure to iAs at the aggregated population level and a second scenario studying exposure at the individual level for a random sub-sample of subjects in each of the three different study areas. These two scenarios only differ in the type of human related input data (i.e., time-activity data, ingestion rates and consumption patterns) that were used, namely averages (incl. probability density functions, PDFs) in the simulation at population level and subject-specific values in the simulation at individual level. The model predictions are shown to be lower than the corresponding biomonitoring data from the monitoring campaign. Urinary tAs levels in adults, irrespective of the area they lived in, were under-predicted by MERLIN-Expo by 40% on average. The model predictions for individual adults, by contrast, under-predict the biomonitoring data by 7% on average, but with more important under-predictions for subjects at the upper end of exposure. Still, average predicted urinary tAs levels from the simulations at population level and at individual level overlap, and, at least for the current case, lead to similar conclusions. These results constitute a first and partial verification of the model performance of MERLIN-Expo when dealing with iAs in a complex site-specific exposure scenario, and demonstrate the robustness of the modelling tool for these situations. Copyright

  8. Concentrations, seasonal and diurnal variations of black carbon in PM2.5 in Shanghai, China

    NASA Astrophysics Data System (ADS)

    Feng, Jialiang; Zhong, Mian; Xu, Binhua; Du, Yan; Wu, Minghong; Wang, Hongli; Chen, Changhong

    2014-10-01

    Concentration of black carbon (BC) in PM2.5 was measured continuously with an aethalometer during January 2010 and December 2011 at an urban site in Shanghai, China. The impact of the emission control measures for the 2010 World Expo and the World Expo event itself on the concentration and temporal variation of BC in Shanghai was discussed. The annually averaged BC concentrations in 2010 and 2011 in Shanghai were 3.8 ± 2.3 μg m- 3 and 3.3 ± 2.1 μg m- 3 respectively. Higher BC concentrations were found in winter and the lowest monthly concentration occurred in September. Comparing with the BC concentration in 2011, lower BC concentration was found in spring of 2010 due to the emission control measures for the Shanghai World Expo and higher BC concentration in summer due to the huge increase of visitors to the World Expo. Distinct bi-modal diurnal variation of BC was found with the highest evening peak concentration in Friday and the lowest in Monday. The diurnal variation of BC matched well with the living style of people in Shanghai and indicated that traffic emission was the main source of BC in urban Shanghai.

  9. Multimedia & PBPK modelling with MERLIN-Expo versus biomonitoring for assessing Pb exposure of pre-school children in a residential setting.

    PubMed

    Fierens, Tine; Van Holderbeke, Mirja; Standaert, Arnout; Cornelis, Christa; Brochot, Céline; Ciffroy, Philippe; Johansson, Erik; Bierkens, Johan

    2016-10-15

    This paper reports on a case study - conducted within the European FP7 project "4FUN" - focusing on exposure of pre-school children to lead resulting from past emissions by non-ferrous smelters in Belgium (Northern Campine area). Exposure scenarios were constructed and simulated with the MERLIN-Expo tool to estimate external Pb exposure as well as the Pb body burden in children living in the vicinity of the former industrial sites as compared to children living in adjacent areas and a reference area. Simulations were run for several scenarios ranging from very simple to rather complex in order to study the effect of different simulation approaches (e.g., deterministic vs. probabilistic, individual vs. aggregated population exposure) and different exposure scenarios (e.g., with vs. without considering local food consumption or time activity patterns) on the model outcomes (predicted concentrations of Pb in environmental and human matrices). This paper discusses the two most complex scenarios, namely exposure at the aggregated population level and at the individual level for a random sub-sample of subjects, respectively. In the final and most realistic exposure scenario, simulating individual lead exposure, model predictions were shown to be higher than the biomonitoring data. Blood Pb levels in children, irrespective of the area they lived in, were overpredicted by MERLIN-Expo with a factor of about 2 on average. The model predictions for individual children overlap with the prediction interval calculated by MERLIN-Expo based on population averages, demonstrating the use of probabilistic approaches in risk assessment. While these results constitute a first verification of the model performance of MERLIN-Expo dealing with inorganic pollutants in a complex real-world exposure scenario and a demonstration of the robustness of the modelling tool, further validation and benchmarking efforts are required for a larger number of inorganic pollutants and different exposure

  10. Comparison of four probabilistic models (CARES(®), Calendex™, ConsExpo, and SHEDS) to estimate aggregate residential exposures to pesticides.

    PubMed

    Young, Bruce M; Tulve, Nicolle S; Egeghy, Peter P; Driver, Jeffrey H; Zartarian, Valerie G; Johnston, Jason E; Delmaar, Christiaan J E; Evans, Jeffrey J; Smith, Luther A; Glen, Graham; Lunchick, Curt; Ross, John H; Xue, Jianping; Barnekow, David E

    2012-09-01

    Two deterministic models (US EPA's Office of Pesticide Programs Residential Standard Operating Procedures (OPP Residential SOPs) and Draft Protocol for Measuring Children's Non-Occupational Exposure to Pesticides by all Relevant Pathways (Draft Protocol)) and four probabilistic models (CARES(®), Calendex™, ConsExpo, and SHEDS) were used to estimate aggregate residential exposures to pesticides. The route-specific exposure estimates for young children (2-5 years) generated by each model were compared to evaluate data inputs, algorithms, and underlying assumptions. Three indoor exposure scenarios were considered: crack and crevice, fogger, and flying insect killer. Dermal exposure estimates from the OPP Residential SOPs and the Draft Protocol were 4.75 and 2.37 mg/kg/day (crack and crevice scenario) and 0.73 and 0.36 mg/kg/day (fogger), respectively. The dermal exposure estimates (99th percentile) for the crack and crevice scenario were 16.52, 12.82, 3.57, and 3.30 mg/kg/day for CARES, Calendex, SHEDS, and ConsExpo, respectively. Dermal exposure estimates for the fogger scenario from CARES and Calendex (1.50 and 1.47 mg/kg/day, respectively) were slightly higher than those from SHEDS and ConsExpo (0.74 and 0.55 mg/kg/day, respectively). The ConsExpo derived non-dietary ingestion estimates (99th percentile) under these two scenarios were higher than those from SHEDS, CARES, and Calendex. All models produced extremely low exposure estimates for the flying insect killer scenario. Using similar data inputs, the model estimates by route for these scenarios were consistent and comparable. Most of the models predicted exposures within a factor of 5 at the 50th and 99th percentiles. The differences identified are explained by activity assumptions, input distributions, and exposure algorithms.

  11. Nanoporous Silicon Ignition of JA2 Propellant

    DTIC Science & Technology

    2014-06-01

    Nanoporous Silicon Ignition of JA2 Propellant Stephen L. Howard Weapons and Materials Research Directorate, ARL Wayne A. Churaman Sensors and... Nanoporous Silicon Ignition of JA2 Propellant by Stephen L. Howard, Wayne A. Churaman, and Luke J. Currano ARL-TR-6950 June 2014...2014 2. REPORT TYPE Final 3. DATES COVERED (From - To) June 2010 4. TITLE AND SUBTITLE Nanoporous Silicon Ignition of JA2 Propellant 5a

  12. Self-reported parental exposure to pesticide during pregnancy and birth outcomes: the MecoExpo cohort study.

    PubMed

    Mayhoub, Flora; Berton, Thierry; Bach, Véronique; Tack, Karine; Deguines, Caroline; Floch-Barneaud, Adeline; Desmots, Sophie; Stéphan-Blanchard, Erwan; Chardon, Karen

    2014-01-01

    The MecoExpo study was performed in the Picardy region of northern France, in order to investigate the putative relationship between parental exposures to pesticides (as reported by the mother) on one hand and neonatal parameters on the other. The cohort comprised 993 mother-newborn pairs. Each mother completed a questionnaire that probed occupational, domestic, environmental and dietary sources of parental exposure to pesticides during her pregnancy. Multivariate regression analyses were then used to test for associations between the characteristics of parental pesticide exposure during pregnancy and the corresponding birth outcomes. Maternal occupational exposure was associated with an elevated risk of low birth weight (odds ratio (OR) [95% confidence interval]: 4.2 [1.2, 15.4]). Paternal occupational exposure to pesticides was associated with a lower than average gestational age at birth (-0.7 weeks; p = 0.0002) and an elevated risk of prematurity (OR: 3.7 [1.4, 9.7]). Levels of domestic exposure to veterinary antiparasitics and to pesticides for indoor plants were both associated with a low birth weight (-70 g; p = 0.02 and -160 g; p = 0.005, respectively). Babies born to women living in urban areas had a lower birth length and a higher risk of low birth length (-0.4 cm, p = 0.006 and OR: 2.9 [1.5, 5.5], respectively). The present study results mainly demonstrate a negative correlation between fetal development on one hand and parental occupational and domestic exposure to pesticides on the other. Our study highlights the need to perform a global and detailed screening of all potential physiological effects when assessing in utero exposure to pesticides.

  13. Self-Reported Parental Exposure to Pesticide during Pregnancy and Birth Outcomes: The MecoExpo Cohort Study

    PubMed Central

    Mayhoub, Flora; Berton, Thierry; Bach, Véronique; Tack, Karine; Deguines, Caroline; Floch-Barneaud, Adeline; Desmots, Sophie; Stéphan-Blanchard, Erwan; Chardon, Karen

    2014-01-01

    The MecoExpo study was performed in the Picardy region of northern France, in order to investigate the putative relationship between parental exposures to pesticides (as reported by the mother) on one hand and neonatal parameters on the other. The cohort comprised 993 mother-newborn pairs. Each mother completed a questionnaire that probed occupational, domestic, environmental and dietary sources of parental exposure to pesticides during her pregnancy. Multivariate regression analyses were then used to test for associations between the characteristics of parental pesticide exposure during pregnancy and the corresponding birth outcomes. Maternal occupational exposure was associated with an elevated risk of low birth weight (odds ratio (OR) [95% confidence interval]: 4.2 [1.2, 15.4]). Paternal occupational exposure to pesticides was associated with a lower than average gestational age at birth (−0.7 weeks; p = 0.0002) and an elevated risk of prematurity (OR: 3.7 [1.4, 9.7]). Levels of domestic exposure to veterinary antiparasitics and to pesticides for indoor plants were both associated with a low birth weight (−70 g; p = 0.02 and −160 g; p = 0.005, respectively). Babies born to women living in urban areas had a lower birth length and a higher risk of low birth length (−0.4 cm, p = 0.006 and OR: 2.9 [1.5, 5.5], respectively). The present study results mainly demonstrate a negative correlation between fetal development on one hand and parental occupational and domestic exposure to pesticides on the other. Our study highlights the need to perform a global and detailed screening of all potential physiological effects when assessing in utero exposure to pesticides. PMID:24949871

  14. 2009 USCG Innovation Expo

    DTIC Science & Technology

    2009-11-19

    temperature and humidity. Slide # 20 Solving World’s Water Problem Namibian Beetle Pill Bug Slide # 21 EMPLOYEE AND CUSTOMER INNOVATION THROUGH...comments on how to improve new concepts, and • rate ideas that should be recommended for implementation • It uses social media concepts to harness the...ONLINE COMMUNITY SPACE 1 Forrester, “Future of Social Web” Social Network Platforms Sponsored Offsite Properties IdeaStorm (EmployeeStorm) Blogs

  15. Science Expo '83.

    ERIC Educational Resources Information Center

    Markle, Sandra; Cichowski, Robert

    1983-01-01

    This article about science fairs provides a list of topics children can research and suggestions for evaluating the possibilities of project ideas before children invest much work in them. Ideas for selecting a fair date and location, choosing judges, and involving parents and the community are included. (PP)

  16. Science Expo '83.

    ERIC Educational Resources Information Center

    Markle, Sandra; Cichowski, Robert

    1983-01-01

    This article about science fairs provides a list of topics children can research and suggestions for evaluating the possibilities of project ideas before children invest much work in them. Ideas for selecting a fair date and location, choosing judges, and involving parents and the community are included. (PP)

  17. L’évaluation et le traitement du nourrisson exposé au virus d’immunodéficience humaine de type 1

    PubMed Central

    2004-01-01

    RÉSUMÉ Dans les pays industrialisés, des soins et un traitement sont offerts aux femmes enceintes et aux nourrissons, afin de faire chuter à 2 % ou moins le taux d’infection périnatale au virus d’immunodéficience humaine de type 1 (VIH-1). Le pédiatre joue un rôle de premier plan dans la prévention de la transmission du VIH-1 de la mère à l’enfant par le dépistage des nourrissons exposés au VIH dont l’infection au VIH de la mère n’a pas été diagnostiquée avant l’accouchement. Il prescrit une prophylaxie antirétrovirale à ces nourrissons, afin de réduire le risque d’acquisition de l’infection au VIH-1 et d’en éviter le plus possible la transmission par le lait maternel. De plus, le pédiatre peut soigner les nourrissons exposés au VIH-1 en les surveillant pour obtenir un dépistage précoce de l’infection au VIH-1 et évaluer les toxicités à court et à long terme de l’exposition aux antirétroviraux, assurer une chimioprophylaxie de la pneumonie à Pneumocystis et soutenir les familles qui vivent avec une infection au VIH-1, grâce à des conseils thérapeutiques aux parents ou aux soignants.

  18. Treatment Plan Adherence for Your Child With JA

    MedlinePlus

    ... Juvenile Arthritis Camps Juvenile Arthritis Conference Resources JA Power Pack Educational Rights Kit JA Transition Toolkit Print ... Drevlow Family: Coping Through Community Tiffany Family Nora Powers: Taking Charge Jodi Van Emmerik: Happy Campers Bridget ...

  19. Effects of MeJA on Arabidopsis metabolome under endogenous JA deficiency

    NASA Astrophysics Data System (ADS)

    Cao, Jingjing; Li, Mengya; Chen, Jian; Liu, Pei; Li, Zhen

    2016-11-01

    Jasmonates (JAs) play important roles in plant growth, development and defense. Comprehensive metabolomics profiling of plants under JA treatment provides insights into the interaction and regulation network of plant hormones. Here we applied high resolution mass spectrometry based metabolomics approach on Arabidopsis wild type and JA synthesis deficiency mutant opr3. The effects of exogenous MeJA treatment on the metabolites of opr3 were investigated. More than 10000 ion signals were detected and more than 2000 signals showed significant variation in different genotypes and treatment groups. Multivariate statistic analyses (PCA and PLS-DA) were performed and a differential compound library containing 174 metabolites with high resolution precursor ion-product ions pairs was obtained. Classification and pathway analysis of 109 identified compounds in this library showed that glucosinolates and tryptophan metabolism, amino acids and small peptides metabolism, lipid metabolism, especially fatty acyls metabolism, were impacted by endogenous JA deficiency and exogenous MeJA treatment. These results were further verified by quantitative reverse transcription PCR (RT-qPCR) analysis of 21 related genes involved in the metabolism of glucosinolates, tryptophan and α-linolenic acid pathways. The results would greatly enhance our understanding of the biological functions of JA.

  20. Effects of MeJA on Arabidopsis metabolome under endogenous JA deficiency.

    PubMed

    Cao, Jingjing; Li, Mengya; Chen, Jian; Liu, Pei; Li, Zhen

    2016-11-24

    Jasmonates (JAs) play important roles in plant growth, development and defense. Comprehensive metabolomics profiling of plants under JA treatment provides insights into the interaction and regulation network of plant hormones. Here we applied high resolution mass spectrometry based metabolomics approach on Arabidopsis wild type and JA synthesis deficiency mutant opr3. The effects of exogenous MeJA treatment on the metabolites of opr3 were investigated. More than 10000 ion signals were detected and more than 2000 signals showed significant variation in different genotypes and treatment groups. Multivariate statistic analyses (PCA and PLS-DA) were performed and a differential compound library containing 174 metabolites with high resolution precursor ion-product ions pairs was obtained. Classification and pathway analysis of 109 identified compounds in this library showed that glucosinolates and tryptophan metabolism, amino acids and small peptides metabolism, lipid metabolism, especially fatty acyls metabolism, were impacted by endogenous JA deficiency and exogenous MeJA treatment. These results were further verified by quantitative reverse transcription PCR (RT-qPCR) analysis of 21 related genes involved in the metabolism of glucosinolates, tryptophan and α-linolenic acid pathways. The results would greatly enhance our understanding of the biological functions of JA.

  1. Effects of MeJA on Arabidopsis metabolome under endogenous JA deficiency

    PubMed Central

    Cao, Jingjing; Li, Mengya; Chen, Jian; Liu, Pei; Li, Zhen

    2016-01-01

    Jasmonates (JAs) play important roles in plant growth, development and defense. Comprehensive metabolomics profiling of plants under JA treatment provides insights into the interaction and regulation network of plant hormones. Here we applied high resolution mass spectrometry based metabolomics approach on Arabidopsis wild type and JA synthesis deficiency mutant opr3. The effects of exogenous MeJA treatment on the metabolites of opr3 were investigated. More than 10000 ion signals were detected and more than 2000 signals showed significant variation in different genotypes and treatment groups. Multivariate statistic analyses (PCA and PLS-DA) were performed and a differential compound library containing 174 metabolites with high resolution precursor ion-product ions pairs was obtained. Classification and pathway analysis of 109 identified compounds in this library showed that glucosinolates and tryptophan metabolism, amino acids and small peptides metabolism, lipid metabolism, especially fatty acyls metabolism, were impacted by endogenous JA deficiency and exogenous MeJA treatment. These results were further verified by quantitative reverse transcription PCR (RT-qPCR) analysis of 21 related genes involved in the metabolism of glucosinolates, tryptophan and α-linolenic acid pathways. The results would greatly enhance our understanding of the biological functions of JA. PMID:27883040

  2. JA but not JA-Ile is the cell-nonautonomous signal activating JA mediated systemic defenses to herbivory in Nicotiana attenuata.

    PubMed

    Bozorov, Tohir A; Dinh, Son Truong; Baldwin, Ian T

    2017-08-01

    The whole-plant activation of defense responses to wounding and herbivory requires systemic signaling in which jasmonates (JAs) play a pivotal role. To examine the nature of the slower cell-nonautonomous as compared to the rapid cell-autonomous signal in mediating systemic defenses in Nicotiana attenuata, reciprocal stem grafting-experiments were used with plants silenced for the JA biosynthetic gene ALLENE OXIDE CYCLASE (irAOC) or plants transformed to create JA sinks by ectopically expressing Arabidopsis JA-O-methyltransferase (ovJMT). JA-impaired irAOC plants were defective in the cell-nonautonomous signaling pathway but not in JA transport. Conversely, ovJMT plants abrogated the production of a graft-transmissible JA signal. Both genotypes displayed unaltered cell-autonomous signaling. Defense responses (17-hydroxygeranyllinalool diterpene glycosides, nicotine, and proteinase inhibitors) and metabolite profiles were differently induced in irAOC and ovJMT scions in response to graft-transmissible signals from elicited wild type stocks. The performance of Manduca sexta larvae on the scions of different graft combinations was consistent with the patterns of systemic defense metabolite elicitations. Taken together, we conclude that JA and possibly MeJA, but not JA-Ile, either directly functions as a long-distance transmissible signal or indirectly interacts with long distance signal(s) to activate systemic defense responses. © 2017 Institute of Botany, Chinese Academy of Sciences.

  3. Aniline is an inducer, and not a precursor, for indole derivatives in Rubrivivax benzoatilyticus JA2.

    PubMed

    Mujahid, Mohammed; Sasikala, Ch; Ramana, Ch V

    2014-01-01

    Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the production of indoles and elucidating the biochemical pathway of indoles in aniline-exposed cells by using stable isotope approaches. Metabolic profiling revealed tryptophan accumulation only in aniline exposed cells along with indole 3-acetic acid (IAA) and indole 3-aldehyde (IAld), the two major catabolites of tryptophan. Deuterium labelled aniline feeding studies revealed that aniline is not a precursor of indoles in strain JA2. Further, production of indoles only in aniline-exposed cells suggests that aniline is an indoles stimulator. In addition, production of indoles depended on the presence of a carbon source, and production enhanced when carbon sources were added to the culture. Isotope labelled fumarate feeding identified, fumarate as the precursor of indole, indicating de novo synthesis of indoles. Glyphosate (shikimate pathway inhibitor) inhibited the indoles production, accumulation of tryptophan, IAA and IAld indicating that indoles synthesis in strain JA2 occurs via the de novo shikimate pathway. The up-regulation of anthranilate synthase gene and induction of anthranilate synthase activity correlated well with tryptophan production in strain JA2. Induction of tryptophan aminotransferase and tryptophan 2-monooxygenase activities corroborated well with IAA levels, suggesting that tryptophan catabolism occurs simultaneously in aniline exposed cells. Our study demonstrates that aniline (stress) stimulates tryptophan/indoles synthesis via the shikimate pathway by possibly modulating the metabolic pathway.

  4. Aniline Is an Inducer, and Not a Precursor, for Indole Derivatives in Rubrivivax benzoatilyticus JA2

    PubMed Central

    Mohammed, Mujahid; Ch, Sasikala; Ch, Ramana V.

    2014-01-01

    Rubrivivax benzoatilyticus JA2 and other anoxygenic photosynthetic bacteria produce indole derivatives when exposed to aniline, a xenobiotic compound. Though this phenomenon has been reported previously, the role of aniline in the production of indoles is still a biochemical riddle. The present study aims at understanding the specific role of aniline (as precursor or stimulator) in the production of indoles and elucidating the biochemical pathway of indoles in aniline-exposed cells by using stable isotope approaches. Metabolic profiling revealed tryptophan accumulation only in aniline exposed cells along with indole 3-acetic acid (IAA) and indole 3-aldehyde (IAld), the two major catabolites of tryptophan. Deuterium labelled aniline feeding studies revealed that aniline is not a precursor of indoles in strain JA2. Further, production of indoles only in aniline-exposed cells suggests that aniline is an indoles stimulator. In addition, production of indoles depended on the presence of a carbon source, and production enhanced when carbon sources were added to the culture. Isotope labelled fumarate feeding identified, fumarate as the precursor of indole, indicating de novo synthesis of indoles. Glyphosate (shikimate pathway inhibitor) inhibited the indoles production, accumulation of tryptophan, IAA and IAld indicating that indoles synthesis in strain JA2 occurs via the de novo shikimate pathway. The up-regulation of anthranilate synthase gene and induction of anthranilate synthase activity correlated well with tryptophan production in strain JA2. Induction of tryptophan aminotransferase and tryptophan 2-monooxygenase activities corroborated well with IAA levels, suggesting that tryptophan catabolism occurs simultaneously in aniline exposed cells. Our study demonstrates that aniline (stress) stimulates tryptophan/indoles synthesis via the shikimate pathway by possibly modulating the metabolic pathway. PMID:24533057

  5. Clinical trial: factors associated with freedom from relapse of heartburn in patients with healed reflux oesophagitis--results from the maintenance phase of the EXPO study.

    PubMed

    Labenz, J; Armstrong, D; Zetterstrand, S; Eklund, S; Leodolter, A

    2009-06-01

    Ability to predict freedom from heartburn relapse during maintenance therapy for healed reflux oesophagitis may facilitate optimal treatment choices for individual patients. To determine factors predicting freedom from heartburn relapse during maintenance proton pump inhibitor therapy in patients with healed reflux oesophagitis. This post-hoc analysis used data from the maintenance phase of the EXPO study (AstraZeneca study code: SH-NEG-0008); 2766 patients with healed reflux oesophagitis and resolved heartburn received once-daily esomeprazole 20 mg or pantoprazole 20 mg for 6 months. Multiple logistic regression analysis determined factors associated with freedom from heartburn relapse. Heartburn relapse rates were lower with esomeprazole than pantoprazole in all subgroups analysed. Esomeprazole treatment was the factor most strongly associated with freedom from heartburn relapse (odds ratio 2.08; P < 0.0001). Other factors significantly associated with freedom from heartburn relapse were Helicobacter pylori infection, greater age, non-obesity, absence of epigastric pain at baseline, pre-treatment nonsevere heartburn and GERD symptom duration < or =5 years. Several factors predict freedom from heartburn relapse during maintenance proton pump inhibitor therapy for healed reflux oesophagitis, the strongest being choice of proton pump inhibitor. These findings outline the importance of optimizing acid control and identifying predictors of relapse for effective long-term symptom management in reflux oesophagitis patients.

  6. Endogenous Bioactive Jasmonate Is Composed of a Set of (+)-7-iso-JA-Amino Acid Conjugates.

    PubMed

    Yan, Jianbin; Li, Suhua; Gu, Min; Yao, Ruifeng; Li, Yuwen; Chen, Juan; Yang, Mai; Tong, Jianhua; Xiao, Langtao; Nan, Fajun; Xie, Daoxin

    2016-12-01

    Jasmonates (JAs) regulate a wide range of plant defense and development processes. The bioactive JA is perceived by its receptor COI1 to trigger the degradation of JASMONATE ZIM-DOMAIN (JAZ) proteins and subsequently derepress the JAZ-repressed transcription factors for activation of expression of JA-responsive genes. So far, (+)-7-iso-JA-l-Ile has been the only identified endogenous bioactive JA molecule. Here, we designed coronafacic acid (CFA) conjugates with all the amino acids (CFA-AA) to mimic the JA amino acid conjugates, and revealed that (+)-7-iso-JA-Leu, (+)-7-iso-JA-Val, (+)-7-iso-JA-Met, and (+)-7-iso-JA-Ala are new endogenous bioactive JA molecules. Furthermore, our studies uncover the general characteristics for all the bioactive JA molecules, and provide a new strategy to synthetically generate novel active JA molecules.

  7. Jasmonic acid treatment to part of the root system is consistent with simulated leaf herbivory, diverting recently assimilated carbon towards untreated roots within an hour.

    PubMed

    Henkes, Gunnar Jakob; Thorpe, Michael R; Minchin, Peter E H; Schurr, Ulrich; Röse, Ursula S R

    2008-09-01

    It is known that shoot application of jasmonic acid (JA) leads to an increased carbon export from leaves to stem and roots, and that root treatment with JA inhibits root growth. Using the radioisotope (11)C, we measured JA effects on carbon partitioning in sterile, split-root, barley plants. JA applied to one root half reduced carbon partitioning to the JA-treated tissue within minutes, whereas the untreated side showed a corresponding--but slower--increase. This response was not observed when instead of applying JA, the sink strength of one root half was reduced by cooling it: there was no enhanced partitioning to the untreated roots. The slower response in the JA-untreated roots, and the difference between the effect of JA and temperature, suggest that root JA treatment caused transduction of a signal from the treated roots to the shoot, leading to an increase in carbon allocation from the leaves to the untreated root tissue, as was indeed observed 10 min after the shoot application of JA. This supports the hypothesis that the response of some plant species to both leaf and root herbivores may be the diversion of resources to safer locations.

  8. Coordinate expression of AOS genes and JA accumulation: JA is not required for initiation of closing layer in wound healing tubers.

    PubMed

    Lulai, Edward; Huckle, Linda; Neubauer, Jonathan; Suttle, Jeffrey

    2011-06-15

    Wounding induces a series of coordinated physiological responses essential for protection and healing of the damaged tissue. Wound-induced formation of jasmonic acid (JA) is important in defense responses in leaves, but comparatively little is known about the induction of JA biosynthesis and its role(s) in tuber wound-healing. In this study, the effects of wounding on JA content, expression of JA biosynthetic genes, and the involvement of JA in the initiation of closing layer formation in potato tubers were determined. In addition, the role of abscisic acid (ABA) in wound-induced JA accumulation was examined. The basal JA content in non-wounded tuber tissues was low (< 3 ng g⁻¹ FW). Two hours after wounding, the JA content increased by > 5-fold, reached a maximum between 4 and 6h after wounding, and declined to near-basal levels thereafter. Tuber age (storage duration) had little effect on the pattern of JA accumulation. The expressions of the JA biosynthetic genes (StAOS2, StAOC, and StOPR3) were greatly increased by wounding reaching a maximum 2-4 h after wounding and declining thereafter. A 1-h aqueous wash of tuber discs immediately after wounding resulted in a 94% inhibition of wound-induced JA accumulation. Neither JA treatment nor inhibition of JA accumulation affected suberin polyphenolic accumulation during closing layer development indicating that JA was not essential for the initiation of primary suberization. ABA treatment did not restore JA accumulation in washed tuber tissues suggesting that leaching of endogenous ABA was either not involved or not solely involved in this loss of JA accumulation by washing. Collectively, these results indicate that JA is not required for the induction of processes essential to the initiation of suberization during closing layer development, but do not exclude the possibility that JA may be involved in other wound related responses. Published by Elsevier GmbH.

  9. RuBPCase activase mediates growth-defense tradeoffs: Silencing RCA redirects JA flux from JA-Ile to MeJA to attenuate induced defense responses in Nicotiana attenuata

    PubMed Central

    Mitra, Sirsha; Baldwin, Ian T.

    2014-01-01

    Summary RuBPCase activase (RCA), an abundant photosynthetic protein is strongly down-regulated in response to Manduca sexta’s oral secretion (OS) in Nicotiana attenuata. RCA-silenced plants are impaired not only in photosynthetic capacity and growth, but also in jasmonic acid (JA)-isoleucine (Ile) signaling, and herbivore resistance mediated by JA-Ile dependent defense traits. These responses are consistent with a resource-based growth-defense trade-off. Since JA+Ile-supplementation of OS restored WT levels of JA-Ile, defenses and resistance to M. sexta, but OS supplemented individually with JA- or Ile did not, the JA-Ile deficiency of RCA-silenced plants could not be attributed to lower JA or Ile pools or JAR4/6 conjugating activity. Similar levels of JA-Ile derivatives after OS elicitation indicated unaltered JA-Ile turnover and lower levels of other JA-conjugates ruled out competition from other conjugation reactions. RCA-silenced plants accumulated more methyl jasmonate (MeJA) after OS elicitation, which corresponded with increased jasmonate methyltransferase (JMT) activity. RCA-silencing phenocopies JMT over-expression, wherein elevated JMT activity redirects OS-elicited JA flux towards inactive MeJA, creating a JA sink which depletes JA-Ile and its associated defense responses. Hence RCA plays an additional non-photosynthetic role in attenuating JA-mediated defenses and their associated costs potentially allowing plants to anticipate resource-based constraints on growth before they actually occur. PMID:24491116

  10. Surveillance urinaire des professionnels de la santé exposés aux antinéoplasiques dans le cadre de leur travail: revue de la littérature de 2010 à 2015

    PubMed Central

    Poupeau, Céline; Roland, Christel; Bussières, Jean-François

    2016-01-01

    RÉSUMÉ Contexte Il existe de plus en plus de données sur la présence de traces de médicaments dangereux dans l’urine des professionnels de la santé exposés à ces médicaments. Objectif Présenter une revue de la littérature scientifique concernant la surveillance urinaire de professionnels de la santé exposés aux anti-néoplasiques dans le cadre de leur travail. Sources de données Recherche sur PubMed avec les Medical Subject Headings (MeSH) « occupational exposure » et « antineoplastic agents » ainsi que sur Google Scholar avec les termes « antineoplastic », « urine » et « occupational exposure ». Sélection des études et extraction des données L’examen a porté sur tous les articles en anglais et en français ayant trait aux professionnels de la santé exposés à des médicaments dangereux dans le cadre de leur travail, publiés entre le 1er janvier 2010 et le 31 décembre 2015. Les articles ne comportant pas de résultats urinaires et ceux concernant les vétérinaires ainsi que les revues de littérature, les éditoriaux, les lettres à la rédaction et les résumés de congrès ont été exclus. Synthèse des données Vingt-quatre articles ont été retenus. Les études ont été menées dans 52 établissements de santé provenant de sept pays. Elles regroupaient 826 travailleurs exposés à des médicaments dangereux et 175 témoins, notamment des infirmiers (n = 16 études), des pharmaciens (n = 10), des assistants techniques en pharmacie (n = 8), des médecins (n = 7), des aides-soignants (n = 2) et autres (n = 8). Différentes méthodes analytiques ont été utilisées pour quantifier la présence de 13 médicaments dangereux, principalement le cyclophosphamide (n = 16 études), les platines (n = 7) et l’alpha-fluoro-béta-alanine, un métabolite urinaire du 5-fluorouracile (n = 3). La proportion de travailleurs qui ont étés déclarés positifs s’étendait de 0 % (n = 10 études) à 100 % (n = 4). Si l’on ne retient que

  11. The University of Jaén Astronomical Observatory

    NASA Astrophysics Data System (ADS)

    Martí, Josep; Luque-Escamilla, Pedro L.; García-Hernández, María T.

    2017-01-01

    We present a description and instrumental characterization of the photometric equipment of the Astronomical Observatory of the University of Jaén. The observatory hosts a 41 cm automated telescope inside a 4 m dome located at the university main campus, in the outskirts of the city of Jaén (Spain). This facility is used for educational, outreach and occasional scientific research on bright stellar objects. Despite the observatory location in a light polluted urban area, its performance for differential photometry studies has proven to be very acceptable. The discovery of the Be star LS I +5979 as a peculiar eclipsing binary system is so far the most relevant achievement.

  12. Genome Analysis of the Biotechnologically Relevant Acidophilic Iron Oxidising Strain JA12 Indicates Phylogenetic and Metabolic Diversity within the Novel Genus “Ferrovum”

    PubMed Central

    Ullrich, Sophie R.; Poehlein, Anja; Tischler, Judith S.; González, Carolina; Ossandon, Francisco J.; Daniel, Rolf; Holmes, David S.; Schlömann, Michael; Mühling, Martin

    2016-01-01

    Background Members of the genus “Ferrovum” are ubiquitously distributed in acid mine drainage (AMD) waters which are characterised by their high metal and sulfate loads. So far isolation and microbiological characterisation have only been successful for the designated type strain “Ferrovum myxofaciens” P3G. Thus, knowledge about physiological characteristics and the phylogeny of the genus “Ferrovum” is extremely scarce. Objective In order to access the wider genetic pool of the genus “Ferrovum” we sequenced the genome of a “Ferrovum”-containing mixed culture and successfully assembled the almost complete genome sequence of the novel “Ferrovum” strain JA12. Phylogeny and Lifestyle The genome-based phylogenetic analysis indicates that strain JA12 and the type strain represent two distinct “Ferrovum” species. “Ferrovum” strain JA12 is characterised by an unusually small genome in comparison to the type strain and other iron oxidising bacteria. The prediction of nutrient assimilation pathways suggests that “Ferrovum” strain JA12 maintains a chemolithoautotrophic lifestyle utilising carbon dioxide and bicarbonate, ammonium and urea, sulfate, phosphate and ferrous iron as carbon, nitrogen, sulfur, phosphorous and energy sources, respectively. Unique Metabolic Features The potential utilisation of urea by “Ferrovum” strain JA12 is moreover remarkable since it may furthermore represent a strategy among extreme acidophiles to cope with the acidic environment. Unlike other acidophilic chemolithoautotrophs “Ferrovum” strain JA12 exhibits a complete tricarboxylic acid cycle, a metabolic feature shared with the closer related neutrophilic iron oxidisers among the Betaproteobacteria including Sideroxydans lithotrophicus and Thiobacillus denitrificans. Furthermore, the absence of characteristic redox proteins involved in iron oxidation in the well-studied acidophiles Acidithiobacillus ferrooxidans (rusticyanin) and Acidithiobacillus

  13. Increased SA in NPR1-silenced plants antagonizes JA and JA-dependent direct and indirect defenses in herbivore-attacked Nicotiana attenuata in nature.

    PubMed

    Rayapuram, Cbgowda; Baldwin, Ian T

    2007-11-01

    The phytohormone jasmonic acid (JA) is known to mediate herbivore resistance, while salicylic acid (SA) and non-expressor of PR-1 (NPR1) mediate pathogen resistance in many plants. Herbivore attack on Nicotiana attenuata elicits increases in JA and JA-mediated defenses, but also increases SA levels and Na-NPR1 transcripts from the plant's single genomic copy. SA treatment of wild-type plants increases Na-NPR1 and Na-PR1 transcripts. Plants silenced in NPR1 accumulation by RNAi (ir-npr1) are highly susceptible to herbivore and pathogen attack when planted in their native habitat in Utah. They are also impaired in their ability to attract Geocorus pallens predators, due to their decreased ability to release cis-alpha-bergamotene, a JA-elicited volatile 'alarm call'. In the glasshouse, Spodoptera exigua larvae grew better on ir-npr1 plants, which had low levels of JA, JA-isoleucine/leucine, lipoxygenase-3 (LOX3) transcripts and JA-elicited direct defense metabolites (nicotine, caffeoyl putrescine and rutin), but high levels of SA and isochorismate synthase (ICS) transcripts, suggesting de novo biosynthesis of SA. A microarray analysis revealed downregulation of many JA-elicited genes and upregulation of SA biosynthetic genes. JA treatment restored nicotine levels and resistance to S. exigua in ir-npr1 plants. We conclude that, during herbivore attack, NPR1 negatively regulates SA production, allowing the unfettered elicitation of JA-mediated defenses; when NPR1 is silenced, the elicited increases in SA production antagonize JA and JA-related defenses, making the plants susceptible to herbivores.

  14. Calcium carbonate overdose

    MedlinePlus

    ... Slovis CM. Electrolyte disorders. In: Marks, JA. ed. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. ... 155. Shoenberger,JM. Constipation. In: Marks, JA. ed. Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ed. ...

  15. 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.

  16. Carbon-carbon cylinder block

    NASA Technical Reports Server (NTRS)

    Ransone, Philip O. (Inventor)

    1995-01-01

    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 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.

  17. Coordinate expression of AOS genes and JA accumulation: JA is not required for initiation of closing layer in wound healing tubers

    USDA-ARS?s Scientific Manuscript database

    Wounding induces a series of coordinated physiological responses essential for protection and healing of the damaged tissue. Wound-induced formation of jasmonic acid (JA) is important in defense responses in leaves, but comparatively little is known about the induction of JA biosynthesis and its ro...

  18. 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

  19. 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

  20. Hierarchical Carbon Fibers with ZnO Nanowires for Volatile Sensing in Composite Curing (Postprint)

    DTIC Science & Technology

    2014-07-01

    AFRL-RX-WP-JA-2014-0171 HIERARCHICAL CARBON FIBERS WITH ZnO NANOWIRES FOR VOLATILE SENSING IN COMPOSITE CURING (POSTPRINT) Gregory...REPORT TYPE Interim 3. DATES COVERED (From – To) 16 April 2012 – 02 June 2014 4. TITLE AND SUBTITLE HIERARCHICAL CARBON FIBERS WITH ZnO NANOWIRES ...needed to demonstrate the use of Zinc Oxide (ZnO) nanowire coated carbon fibers as a volatile sensor. ZnO nanowires are demonstrated to function as

  1. 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.

  2. Effect of MeJA treatment on polyamine, energy status and anthracnose rot of loquat fruit.

    PubMed

    Cao, Shifeng; Cai, Yuting; Yang, Zhenfeng; Joyce, Daryl C; Zheng, Yonghua

    2014-02-15

    The effect of methyl jasmonate (MeJA) on changes in polyamines content and energy status and their relation to disease resistance was investigated. Freshly harvested loquat fruit were treated with 10 μmol l(-1) MeJA and wound inoculated with Colletotrichum acutatum spore suspension (1.0 × 10(5) spores ml(-1)) after 24h, and then stored at 20 °C for 6 days. MeJA treatment significantly reduced decay incidence. MeJA treated fruit manifested higher contents of polyamines (putrescine, spermidine and spermine) compared with the control fruit, during storage. MeJA treatment also maintained higher levels of adenosine triphosphate, and suppressed an increase in adenosine monophosphate content in loquat fruit. These results suggest that MeJA treatment may inhibit anthracnose rot by increasing polyamine content and maintaining the energy status. Copyright © 2013. Published by Elsevier Ltd.

  3. Mitochondrial chaperone DnaJA3 induces Drp1-dependent mitochondrial fragmentation.

    PubMed

    Elwi, Adam N; Lee, Byoungchun; Meijndert, H Christopher; Braun, Janice E A; Kim, Sung-Woo

    2012-08-01

    Mitochondrial morphology is dynamic and controlled by coordinated fusion and fission pathways. The role of mitochondrial chaperones in mitochondrial morphological changes and pathology is currently unclear. Here we report that altered levels of DnaJA3 (Tid1/mtHsp40) a mitochondrial member of the DnaJ protein family, and heat shock protein (Hsp) co-chaperone of matrix 70 kDa Hsp70 (mtHsp70/mortalin/HSPA9), induces mitochondrial fragmentation. Suppression of DnaJA3 induced mitochondrial fragmentation in HeLa cells. Elevated levels of DnaJA3 in normal Hs68 fibroblast cells and HeLa, SKN-SH, U87 and U251 cancer cell lines induces mitochondrial fragmentation. Mitochondrial fragmentation induction was not observed in HeLa cells when other DnaJA family members, or mitochondrial DnaJ protein HSC20, were ectopically expressed, indicating that the effects on mitochondrial morphology were specific to DnaJA3. We show that the DnaJ domain (amino acids 88-168) of DnaJA3 is sufficient for the induction of mitochondrial fragmentation. Furthermore, an H121Q point mutation of the DnaJ domain, which abrogates interaction and activation of mtHsp70 ATPase, eliminates fragmentation induced by DnaJA3. This suggests that DnaJA3 interaction with mtHsp70 may be critical in mitochondrial morphological changes. DnaJA3-induced mitochondrial fragmentation was dependent on fission factor dynamin-related protein 1 (Drp1). Ectopic expression of the mitofusins (Mfn1 and Mfn2), however, does not rescue DnaJA3-induced mitochondrial fragmentation. Lastly, elevated levels of DnaJA3 inducing mitochondrial fragmentation were associated with reduction in cell viability. Taken together, elevated DnaJA3 induces Drp1-depedendent mitochondrial fragmentation and decreased cell viability.

  4. Synthesis, structural characterization and biological activity of two diastereomeric JA-Ile macrolactones.

    PubMed

    Jimenez-Aleman, Guillermo H; Machado, Ricardo A R; Görls, Helmar; Baldwin, Ian T; Boland, Wilhelm

    2015-06-07

    Jasmonates are phytohormones involved in a wide range of plant processes, including growth, development, senescence, and defense. Jasmonoyl-L-isoleucine (JA-Ile, 2), an amino acid conjugate of jasmonic acid (JA, 1), has been identified as a bioactive endogenous jasmonate. However, JA-Ile (2) analogues trigger different responses in the plant. ω-Hydroxylation of the pentenyl side chain leads to the inactive 12-OH-JA-Ile (3) acting as a “stop” signal. On the other hand, a lactone derivative of 12-OH-JA (5) (jasmine ketolactone, JKL) occurs in nature, although with no known biological function. Inspired by the chemical structure of JKL (6) and in order to further explore the potential biological activities of 12-modified JA-Ile derivatives, we synthesized two macrolactones (JA-Ile-lactones (4a) and (4b)) derived from 12-OH-JA-Ile (3). The biological activity of (4a) and (4b) was tested for their ability to elicit nicotine production, a well-known jasmonate dependent secondary metabolite. Both macrolactones showed strong biological activity, inducing nicotine accumulation to a similar extent as methyl jasmonate does in Nicotiana attenuata leaves. Surprisingly, the highest nicotine contents were found in plants treated with the JA-Ile-lactone (4b), which has (3S,7S) configuration at the cyclopentanone not known from natural jasmonates. Macrolactone (4a) is a valuable standard to explore for its occurrence in nature.

  5. The mealybug Phenacoccus solenopsis suppresses plant defense responses by manipulating JA-SA crosstalk

    PubMed Central

    Zhang, Peng-Jun; Huang, Fang; Zhang, Jin-Ming; Wei, Jia-Ning; Lu, Yao-Bin

    2015-01-01

    Induced plant defenses against herbivores are modulated by jasmonic acid-, salicylic acid-, and ethylene-signaling pathways. Although there is evidence that some pathogens suppress plant defenses by interfering with the crosstalk between different signaling pathways, such evidence is scarce for herbivores. Here, we demonstrate that the mealybug Phenacoccus solenopsis suppresses the induced defenses in tomato. We found that exogenous JA, but not SA, significantly decreased mealybug feeding time and reduced nymphal performance. In addition, constitutive activation of JA signaling in 35s::prosys plants reduced mealybug survival. These data indicate that the JA signaling pathway plays a key role in mediating the defense responses against P. solenopsis. We also found that mealybug feeding decreased JA production and JA-dependent defense gene expression, but increased SA accumulation and SA-dependent gene expression. In SA-deficient plants, mealybug feeding did not suppress but activated JA accumulation, indicating that the suppression of JA-regulated defenses depends on the SA signaling pathway. Mealybugs benefit from suppression of JA-regulated defenses by exhibiting enhanced nymphal performance. These findings confirm that P. solenopsis manipulates plants for its own benefits by modulating the JA-SA crosstalk and thereby suppressing induced defenses. PMID:25790868

  6. Calcium Carbonate

    MedlinePlus

    Calcium carbonate is a dietary supplement used when the amount of calcium taken in the diet is not ... for healthy bones, muscles, nervous system, and heart. Calcium carbonate also is used as an antacid to relieve ...

  7. 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.

  8. Novel bioactive oxazolomycin isomers produced by Streptomyces albus JA3453.

    PubMed

    Kanzaki, H; Wada, K; Nitoda, T; Kawazu, K

    1998-03-01

    Two novel oxazolomycin isomers, oxazolomycins B (2) and C (3), were isolated from the fermentation broth of an oxazolomycin-producing strain, Streptomyces albus JA3453. Both compounds are geometrical isomers of oxazolomycin (1), the configurations of their triene moieties being (4'E, 6'E, 8'E) (2) and (4'Z, 6'E, 8'E) (3) while that of oxazolomycin (1) is (4'Z, 6'Z, 8'E). Compounds 2 and 3 exhibited potent inhibitory activity against crown gall formation with the same MIC (0.8 microgram/disk) as oxazolomycin. Compounds 2 and 3 showed no antibacterial activity against Agrobacterium tumefaciens, in contrast to oxazolomycin which has specific anti-A. tumefaciens activity.

  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. 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.

  11. 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.

  12. Carbon-On-Carbon Manufacturing

    NASA Technical Reports Server (NTRS)

    Mungas, Gregory S. (Inventor); Buchanan, Larry (Inventor); Banzon, Jr., Jose T. (Inventor)

    2017-01-01

    The presently disclosed technology relates to carbon-on-carbon (C/C) manufacturing techniques and the resulting C/C products. One aspect of the manufacturing techniques disclosed herein utilizes two distinct curing operations that occur at different times and/or using different temperatures. The resulting C/C products are substantially non-porous, even though the curing operation(s) substantially gasify a liquid carbon-entrained filler material that saturates a carbon fabric that makes up the C/C products.

  13. 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)

  14. Continuous Dust Formation in SNe 2010jl and 2011ja

    NASA Astrophysics Data System (ADS)

    Krafton, Kelsie; Clayton, Geoffrey; Andrews, Jennifer; Barlow, Michael; De Looze, Ilse

    2016-08-01

    Studies in the last 10 years of dust formation in core-collapse supernovae (CCSNe) have found only small amounts, ~0.001 solar masses. This is far less than the amount needed to account for the large masses of dust seen in some high redshift galaxies. However, the recent discovery of ~1 solar mass of cold dust in the ejecta of SN 1987A has has caused a complete re-evaluation of dust formation in CCSNe. It has been suggested that the CCSNe are continuously forming dust so that by the time they are about 25 years old they will have dust masses similar to SN 1987A. However, there is a wide time gap between the CCSNe that have been studied recently and SN 1987A. We plan to use the sensitivity of Spitzer to detect dust emission from CCSNe 5 or more years after explosion. Radiative transfer models will be used to estimate the dust masses. This proposal is to continue our study of two interesting SNe 2010jl and 2011ja. These observations are part of a long term study requiring multiple epochs of Spitzer observations to look for evidence of continuous dust formation. These observations will help shed light on the mystery of dust in SN 1987A.

  15. THE PROGENITOR OF SN 2011ja: CLUES FROM CIRCUMSTELLAR INTERACTION

    SciTech Connect

    Chakraborti, Sayan; Ray, Alak; Yadav, Naveen; Smith, Randall; Ryder, Stuart; Sutaria, Firoza; Dwarkadas, Vikram V.; Chandra, Poonam; Pooley, David; Roy, Rupak

    2013-09-01

    Massive stars, possibly red supergiants, which retain extended hydrogen envelopes until core collapse, produce Type II plateau (IIP) supernovae. The ejecta from these explosions shocks the circumstellar matter originating from the mass loss of the progenitor during the final phases of its life. This interaction accelerates particles to relativistic energies which then lose energy via synchrotron radiation in the shock-amplified magnetic fields and inverse Compton scattering against optical photons from the supernova. These processes produce different signatures in the radio and X-ray parts of the electromagnetic spectrum. Observed together, they allow us to break the degeneracy between shock acceleration and magnetic field amplification. In this work, we use X-rays observations from the Chandra and radio observations from the Australia Telescope Compact Array to study the relative importance of processes which accelerate particles and those which amplify magnetic fields in producing the non-thermal radiation from SN 2011ja. We use radio observations to constrain the explosion date. Multiple Chandra observations allow us to probe the history of variable mass loss from the progenitor. The ejecta expands into a low-density bubble followed by interaction with a higher density wind from a red supergiant consistent with M{sub ZAMS} {approx}> 12 M{sub Sun }. Our results suggest that a fraction of Type IIP supernovae may interact with circumstellar media set up by non-steady winds.

  16. 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.

  17. Calcium carbonate with magnesium overdose

    MedlinePlus

    ... K. General approach to the poisoned patient. In: Marx JA, Hockberger RS, Walls RM, eds. Rosen's Emergency ... 147. Pfennig CL, Slovis CM. Electrolyte disorders. In: Marx JA, Hockberger RS, Walls RM, eds. Rosen's Emergency ...

  18. Mutations in jasmonoyl-L-isoleucine-12-hydroxylases suppress multiple JA-dependent wound responses in Arabidopsis thaliana.

    PubMed

    Poudel, Arati N; Zhang, Tong; Kwasniewski, Misha; Nakabayashi, Ryo; Saito, Kazuki; Koo, Abraham J

    2016-09-01

    Plants rapidly perceive tissue damage, such as that inflicted by insects, and activate several key defense responses. The importance of the fatty acid-derived hormone jasmonates (JA) in dictating these wound responses has been recognized for many years. However, important features pertaining to the regulation of the JA pathway are still not well understood. One key unknown is the inactivation mechanism of the JA pathway and its relationship with plant response to wounding. Arabidopsis cytochrome P450 enzymes in the CYP94 clade metabolize jasmonoyl-L-isoleucine (JA-Ile), a major metabolite of JA responsible for many biological effects attributed to the JA signaling pathway; thus, CYP94s are expected to contribute to the attenuation of JA-Ile-dependent wound responses. To directly test this, we created the double and triple knock-out mutants of three CYP94 genes, CYP94B1, CYP94B3, and CYP94C1. The mutations blocked the oxidation steps and caused JA-Ile to accumulate 3-4-fold the WT levels in the wounded leaves. Surprisingly, over accumulation of JA-Ile did not lead to a stronger wound response. On the contrary, the mutants displayed a series of symptoms reminiscent of JA-Ile deficiency, including resistance to wound-induced growth inhibition, decreased anthocyanin and trichomes, and increased susceptibility to insects. The mutants, however, responded normally to exogenous JA treatments, indicating that JA perception or signaling pathways were intact. Untargeted metabolite analyses revealed >40% reduction in wound-inducible metabolites in the mutants. These observations raise questions about the current JA signaling model and point toward a more complex model perhaps involving JA derivatives and/or feedback mechanisms. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Carbon cyclist

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    A satellite launched in early August as part of NASA's Mission to Planet Earth could dramatically increase understanding of how carbon cycles through the Earth's biosphere and living organisms and how this process influences global climate. The Sea-viewing Wide Field-of-View Sensor (SeaWiFS) will measure the color of the oceans with a radiometer to determine the concentration of chlorophyll found in oceanic phytoplankton. The single-celled plants, at the base of food chains around the world, remove carbon dioxide from seawater through photosynthesis, which allows oceans to absorb more carbon dioxide from the atmosphere.

  20. Update from the Japanese Center for the Validation of Alternative Methods (JaCVAM).

    PubMed

    Kojima, Hajime

    2013-12-01

    The Japanese Center for the Validation of Alternative Methods (JaCVAM) was established in 2005 to promote the use of alternatives to animal testing in regulatory studies, thereby replacing, reducing, or refining the use of animals, according to the Three Rs principles. JaCVAM assesses the utility, limitations and suitability for use in regulatory studies, of test methods needed to determine the safety of chemicals and other materials. JaCVAM also organises and performs validation studies of new test methods, when necessary. In addition, JaCVAM co-operates and collaborates with similar organisations in related fields, both in Japan and internationally, which also enables JaCVAM to provide input during the establishment of guidelines for new alternative experimental methods. These activities help facilitate application and approval processes for the manufacture and sale of pharmaceuticals, chemicals, pesticides, and other products, as well as for revisions to standards for cosmetic products. In this manner, JaCVAM plays a leadership role in the introduction of new alternative experimental methods for regulatory acceptance in Japan.

  1. Shared binding sites in Lepidoptera for Bacillus thuringiensis Cry1Ja and Cry1A toxins.

    PubMed

    Herrero, S; González-Cabrera, J; Tabashnik, B E; Ferré, J

    2001-12-01

    Bacillus thuringiensis toxins act by binding to specific target sites in the insect midgut epithelial membrane. The best-known mechanism of resistance to B. thuringiensis toxins is reduced binding to target sites. Because alteration of a binding site shared by several toxins may cause resistance to all of them, knowledge of which toxins share binding sites is useful for predicting cross-resistance. Conversely, cross-resistance among toxins suggests that the toxins share a binding site. At least two strains of diamondback moth (Plutella xylostella) with resistance to Cry1A toxins and reduced binding of Cry1A toxins have strong cross-resistance to Cry1Ja. Thus, we hypothesized that Cry1Ja shares binding sites with Cry1A toxins. We tested this hypothesis in six moth and butterfly species, each from a different family: Cacyreus marshalli (Lycaenidae), Lobesia botrana (Tortricidae), Manduca sexta (Sphingidae), Pectinophora gossypiella (Gelechiidae), P. xylostella (Plutellidae), and Spodoptera exigua (Noctuidae). Although the extent of competition varied among species, experiments with biotinylated Cry1Ja and radiolabeled Cry1Ac showed that Cry1Ja and Cry1Ac competed for binding sites in all six species. A recent report also indicates shared binding sites for Cry1Ja and Cry1A toxins in Heliothis virescens (Noctuidae). Thus, shared binding sites for Cry1Ja and Cry1A occur in all lepidopteran species tested so far.

  2. 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.

  3. Expo IGNITES Interest in Manufacturing Careers

    ERIC Educational Resources Information Center

    Wilhelm, Karen

    2009-01-01

    On a pleasant September day, 400 high school students and 40 teachers converged on the Careers in Technology, Engineering, and Manufacturing Day at the IGNITE manufacturing industry trade show, held in Grand Rapids, Michigan, and sponsored by the Society of Manufacturing Engineers (SME). These weren't students getting out of school for a day to go…

  4. Expo IGNITES Interest in Manufacturing Careers

    ERIC Educational Resources Information Center

    Wilhelm, Karen

    2009-01-01

    On a pleasant September day, 400 high school students and 40 teachers converged on the Careers in Technology, Engineering, and Manufacturing Day at the IGNITE manufacturing industry trade show, held in Grand Rapids, Michigan, and sponsored by the Society of Manufacturing Engineers (SME). These weren't students getting out of school for a day to go…

  5. 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. © 2016 Elsevier Inc. All rights reserved.

  6. 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.

  7. Lotus japonicus nodulation is photomorphogenetically controlled by sensing the red/far red (R/FR) ratio through jasmonic acid (JA) signaling

    PubMed Central

    Suzuki, Akihiro; Suriyagoda, Lalith; Shigeyama, Tamaki; Tominaga, Akiyoshi; Sasaki, Masayo; Hiratsuka, Yoshimi; Yoshinaga, Aya; Arima, Susumu; Agarie, Sakae; Sakai, Tatsuya; Inada, Sayaka; Jikumaru, Yusuke; Kamiya, Yuji; Uchiumi, Toshiki; Abe, Mikiko; Hashiguchi, Masatsugu; Akashi, Ryo; Sato, Shusei; Kaneko, Takakazu; Tabata, Satoshi; Hirsch, Ann M.

    2011-01-01

    Light is critical for supplying carbon to the energetically expensive, nitrogen-fixing symbiosis between legumes and rhizobia. Here, we show that phytochrome B (phyB) is part of the monitoring system to detect suboptimal light conditions, which normally suppress Lotus japonicus nodule development after Mesorhizobium loti inoculation. We found that the number of nodules produced by L. japonicus phyB mutants is significantly reduced compared with the number produced of WT Miyakojima MG20. To explore causes other than photoassimilate production, the possibility that local control by the root genotype occurred was investigated by grafting experiments. The results showed that the shoot and not the root genotype is responsible for root nodule formation. To explore systemic control mechanisms exclusive of photoassimilation, we moved WT MG20 plants from white light to conditions that differed in their ratios of low or high red/far red (R/FR) light. In low R/FR light, the number of MG20 root nodules dramatically decreased compared with plants grown in high R/FR, although photoassimilate content was higher for plants grown under low R/FR. Also, the expression of jasmonic acid (JA) -responsive genes decreased in both low R/FR light-grown WT and white light-grown phyB mutant plants, and it correlated with decreased jasmonoyl-isoleucine content in the phyB mutant. Moreover, both infection thread formation and root nodule formation were positively influenced by JA treatment of WT plants grown in low R/FR light and white light-grown phyB mutants. Together, these results indicate that root nodule formation is photomorphogenetically controlled by sensing the R/FR ratio through JA signaling. PMID:21930895

  8. Carbon sequestration.

    PubMed

    Lal, Rattan

    2008-02-27

    Developing technologies to reduce the rate of increase of atmospheric concentration of carbon dioxide (CO2) from annual emissions of 8.6PgCyr-1 from energy, process industry, land-use conversion and soil cultivation is an important issue of the twenty-first century. Of the three options of reducing the global energy use, developing low or no-carbon fuel and sequestering emissions, this manuscript describes processes for carbon (CO2) sequestration and discusses abiotic and biotic technologies. Carbon sequestration implies transfer of atmospheric CO2 into other long-lived global pools including oceanic, pedologic, biotic and geological strata to reduce the net rate of increase in atmospheric CO2. Engineering techniques of CO2 injection in deep ocean, geological strata, old coal mines and oil wells, and saline aquifers along with mineral carbonation of CO2 constitute abiotic techniques. These techniques have a large potential of thousands of Pg, are expensive, have leakage risks and may be available for routine use by 2025 and beyond. In comparison, biotic techniques are natural and cost-effective processes, have numerous ancillary benefits, are immediately applicable but have finite sink capacity. Biotic and abiotic C sequestration options have specific nitches, are complementary, and have potential to mitigate the climate change risks.

  9. Expression of a Flax Allene Oxide Synthase cDNA Leads to Increased Endogenous Jasmonic Acid (JA) Levels in Transgenic Potato Plants but Not to a Corresponding Activation of JA-Responding Genes.

    PubMed Central

    Harms, K.; Atzorn, R.; Brash, A.; Kuhn, H.; Wasternack, C.; Willmitzer, L.; Pena-Cortes, H.

    1995-01-01

    Both jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are thought to be significant components of the signaling pathway regulating the expression of plant defense genes in response to various stresses. JA and MeJA are plant lipid derivatives synthesized from [alpha]-linolenic acid by a lipoxygenase-mediated oxygenation leading to 13-hydroperoxylinolenic acid, which is subsequently transformed by the action of allene oxide synthase (AOS) and additional modification steps. AOS converts lipoxygenase-derived fatty acid hydroperoxide to allene epoxide, which is the precursor for JA formation. Overexpression of flax AOS cDNA under the regulation of the cauliflower mosaic virus 35S promoter in transgenic potato plants led to an increase in the endogenous level of JA. Transgenic plants had six- to 12-fold higher levels of JA than the nontransformed plants. Increased levels of JA have been observed when potato and tomato plants are mechanically wounded. Under these conditions, the proteinase inhibitor II (pin2) genes are expressed in the leaves. Despite the fact that the transgenic plants had levels of JA similar to those found in nontransgenic wounded plants, pin2 genes were not constitutively expressed in the leaves of these plants. Transgenic plants with increased levels of JA did not show changes in water state or in the expression of water stress-responsive genes. Furthermore, the transgenic plants overexpressing the flax AOS gene, and containing elevated levels of JA, responded to wounding or water stress by a further increase in JA and by activating the expression of either wound- or water stress-inducible genes. Protein gel blot analysis demonstrated that the flax-derived AOS protein accumulated in the chloroplasts of the transgenic plants. PMID:12242357

  10. 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.

  11. Manual of carbonate sedimentology

    SciTech Connect

    Reijers, T.J.; Hsu, K.S.

    1986-01-01

    This manual, organised along encycolopaedic/lexicographic lines, summarizes information on the properties and characteristics of carbonates and their environments. Part 1 deals with the elements of carbonates; Part 2 with environments, settings, and carbonate bodies; Part 3 with carbonate diagenesis, and Part 4 with carbonate reservoirs. Contents include: Elements of carbonates; Carbonate Environments, Settings and Bodies; Carbonate diagenesis; Carbonate reservoirs; Alphabetical Indices; English, Dutch, German, Spanish, French Computer Compatible Codes; Commonly Used (Informal) abbreviations.

  12. Engineering the Activity and Lifetime of Heterogeneous Catalysts for Carbon Nanotube Growth via Substrate Ion Beam Bombardment (Postprint)

    DTIC Science & Technology

    2014-07-31

    AFRL-RX-WP-JA-2014-0159 ENGINEERING THE ACTIVITY AND LIFETIME OF HETEROGENEOUS CATALYSTS FOR CARBON NANOTUBE GROWTH VIA SUBSTRATE ION BEAM...July 2014 4. TITLE AND SUBTITLE ENGINEERING THE ACTIVITY AND LIFETIME OF HETEROGENEOUS CATALYSTS FOR CARBON NANOTUBE GROWTH VIA SUBSTRATE ION BEAM... heterogeneous catalyst, catalyst support, ion beam bombardment 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT SAR 18. NUMBER OF PAGES 11

  13. Optimal functional levels of activation-induced deaminase specifically require the Hsp40 DnaJa1

    PubMed Central

    Orthwein, Alexandre; Zahn, Astrid; Methot, Stephen P; Godin, David; Conticello, Silvestro G; Terada, Kazutoyo; Di Noia, Javier M

    2012-01-01

    The enzyme activation-induced deaminase (AID) deaminates deoxycytidine at the immunoglobulin genes, thereby initiating antibody affinity maturation and isotype class switching during immune responses. In contrast, off-target DNA damage caused by AID is oncogenic. Central to balancing immunity and cancer is AID regulation, including the mechanisms determining AID protein levels. We describe a specific functional interaction between AID and the Hsp40 DnaJa1, which provides insight into the function of both proteins. Although both major cytoplasmic type I Hsp40s, DnaJa1 and DnaJa2, are induced upon B-cell activation and interact with AID in vitro, only DnaJa1 overexpression increases AID levels and biological activity in cell lines. Conversely, DnaJa1, but not DnaJa2, depletion reduces AID levels, stability and isotype switching. In vivo, DnaJa1-deficient mice display compromised response to immunization, AID protein and isotype switching levels being reduced by half. Moreover, DnaJa1 farnesylation is required to maintain, and farnesyltransferase inhibition reduces, AID protein levels in B cells. Thus, DnaJa1 is a limiting factor that plays a non-redundant role in the functional stabilization of AID. PMID:22085931

  14. 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

  15. Carbon tetrachloride

    Integrated Risk Information System (IRIS)

    Carbon tetrachloride ; CASRN 56 - 23 - 5 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 Noncarcinogen

  16. A balanced JA/ABA status may correlate with adaptation to osmotic stress in Vitis cells.

    PubMed

    Ismail, Ahmed; Seo, Mitsunori; Takebayashi, Yumiko; Kamiya, Yuji; Nick, Peter

    2015-08-01

    Water-related stress is considered a major type of plant stress. Osmotic stress, in particular, represents the common part of all water-related stresses. Therefore, plants have evolved different adaptive mechanisms to cope with osmotic-related disturbances. In the current work, two grapevine cell lines that differ in their osmotic adaptability, Vitis rupestris and Vitis riparia, were investigated under mannitol-induced osmotic stress. To dissect signals that lead to adaptability from those related to sensitivity, osmotic-triggered responses with respect to jasmonic acid (JA) and its active form JA-Ile, abscisic acid (ABA), and stilbene compounds, as well as the expression of their related genes were observed. In addition, the transcript levels of the cellular homeostasis gene NHX1 were examined. The data are discussed with a hypothesis suggesting that a balance of JA and ABA status might correlate with cellular responses, either guiding cells to sensitivity or to progress toward adaptation.

  17. 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

  18. Effects of jasmonic acid, branching and girdling on carbon and nitrogen transport in poplar.

    PubMed

    Appel, Heidi M; Arnold, Thomas M; Schultz, Jack C

    2012-07-01

    • Here, we examined the impact of jasmonate (JA) treatment, branching and phloem girdling on ¹³C and ¹⁵N import, invertase activity and polyphenol accumulation in juvenile tissues of unbranched and branched hybrid poplar saplings (Populus nigra × P. deltoides). • The import of ¹³C to juvenile tissues was positively correlated with invertase activity at the treatment site and enhanced by JA. Both invertase activity and ¹³C import were greater in shorter, younger branches and smaller, younger leaves. By contrast, JA treatments, branching and girdling had little or no impact on ¹⁵N import. • In poplar saplings with multiple lateral branches, we observed almost no ¹³C movement from subtending source leaves into lateral branches above them, with or without JA treatment. The presence of potentially competing branches, treated with JA or not, girdled or not, had no impact on carbohydrate (CHO) import or polyphenol accumulation in target branches. • We conclude that poplar branches comprise modules that are relatively independent from each other and from the stem below in terms of CHO movement, carbon-based defence production and response to elicitors. By contrast, branches are closely linked modules in terms of nitrogen movement. This should produce trees that are highly heterogeneous in quality for herbivores. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  19. 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.

  20. Dermal sensitization potential of ja-2 solid propellant in guinea pigs. Report for 4 April-9 May 1986

    SciTech Connect

    Lewis, C.M.; Brown, L.D.; Korte, D.W.

    1989-11-01

    JA-2 Solid Propellant was evaluated for its potential to produce dermal sensitization in male guinea pigs. The Buehler test, which utilizes repeated closed patch inductions with the test compound, was used for this evaluation. No evidence that JA-2 Solid Propellant induced sensitization was obtained in the study.

  1. 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.

  2. Carbon investment funds

    SciTech Connect

    2007-01-15

    The report is a study of the development of funds to invest in the purchase of carbon credits. It takes a look at the growing market for carbon credits, the rise of carbon investment funds, and the current state of carbon investing. Topics covered in the report include: Overview of climate change, greenhouse gases, and the Kyoto Protocols. Analysis of the alternatives for reducing carbon emissions including nitrous oxide reduction, coal mine methane capture and carbon capture and storage; Discussion of the different types of carbon credits; Discussion of the basics of carbon trading; Evaluation of the current status of carbon investing; and Profiles of 37 major carbon investment funds worldwide.

  3. Integrated metabolomic and proteomic analysis reveals systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress.

    PubMed

    Mujahid, Md; Prasuna, M Lakshmi; Sasikala, Ch; Ramana, Ch Venkata

    2015-02-06

    Aromatic amines are widely distributed in the environment and are major environmental pollutants. Although degradation of aromatic amines is well studied in bacteria, physiological adaptations and stress response to these toxic compounds is not yet fully understood. In the present study, systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress were deciphered using metabolite and iTRAQ-labeled protein profiling. Strain JA2 tolerated high concentrations of aniline (30 mM) with trace amounts of aniline being transformed to acetanilide. GC-MS metabolite profiling revealed aniline stress phenotype wherein amino acid, carbohydrate, fatty acid, nitrogen metabolisms, and TCA (tricarboxylic acid cycle) were modulated. Strain JA2 responded to aniline by remodeling the proteome, and cellular functions, such as signaling, transcription, translation, stress tolerance, transport and carbohydrate metabolism, were highly modulated. Key adaptive responses, such as transcription/translational changes, molecular chaperones to control protein folding, and efflux pumps implicated in solvent extrusion, were induced in response to aniline stress. Proteo-metabolomics indicated extensive rewiring of metabolism to aniline. TCA cycle and amino acid catabolism were down-regulated while gluconeogenesis and pentose phosphate pathways were up-regulated, leading to the synthesis of extracellular polymeric substances. Furthermore, increased saturated fatty acid ratios in membranes due to aniline stress suggest membrane adaptation. The present study thus indicates that strain JA2 employs multilayered responses: stress response, toxic compound tolerance, energy conservation, and metabolic rearrangements to aniline.

  4. Transcriptome Analysis in Haematococcus pluvialis: Astaxanthin Induction by Salicylic Acid (SA) and Jasmonic Acid (JA).

    PubMed

    Gao, Zhengquan; Li, Yan; Wu, Guanxun; Li, Guoqiang; Sun, Haifeng; Deng, Suzhen; Shen, Yicheng; Chen, Guoqiang; Zhang, Ruihao; Meng, Chunxiao; Zhang, Xiaowen

    2015-01-01

    Haematococcus pluvialis is an astaxanthin-rich microalga that can increase its astaxanthin production by salicylic acid (SA) or jasmonic acid (JA) induction. The genetic transcriptome details of astaxanthin biosynthesis were analyzed by exposing the algal cells to 25 mg/L of SA and JA for 1, 6 and 24 hours, plus to the control (no stress). Based on the RNA-seq analysis, 56,077 unigenes (51.7%) were identified with functions in response to the hormone stress. The top five identified subcategories were cell, cellular process, intracellular, catalytic activity and cytoplasm, which possessed 5600 (~9.99%), 5302 (~9.45%), 5242 (~9.35%), 4407 (~7.86%) and 4195 (~7.48%) unigenes, respectively. Furthermore, 59 unigenes were identified and assigned to 26 putative transcription factors (TFs), including 12 plant-specific TFs. They were likely associated with astaxanthin biosynthesis in Haematococcus upon SA and JA stress. In comparison, the up-regulation of differential expressed genes occurred much earlier, with higher transcript levels in the JA treatment (about 6 h later) than in the SA treatment (beyond 24 h). These results provide valuable information for directing metabolic engineering efforts to improve astaxanthin biosynthesis in H. pluvialis.

  5. 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.

  6. Partial Activation of SA- and JA-Defensive Pathways in Strawberry upon Colletotrichum acutatum Interaction

    PubMed Central

    Amil-Ruiz, Francisco; Garrido-Gala, José; Gadea, José; Blanco-Portales, Rosario; Muñoz-Mérida, Antonio; Trelles, Oswaldo; de los Santos, Berta; Arroyo, Francisco T.; Aguado-Puig, Ana; Romero, Fernando; Mercado, José-Ángel; Pliego-Alfaro, Fernando; Muñoz-Blanco, Juan; Caballero, José L.

    2016-01-01

    Understanding the nature of pathogen host interaction may help improve strawberry (Fragaria × ananassa) cultivars. Plant resistance to pathogenic agents usually operates through a complex network of defense mechanisms mediated by a diverse array of signaling molecules. In strawberry, resistance to a variety of pathogens has been reported to be mostly polygenic and quantitatively inherited, making it difficult to associate molecular markers with disease resistance genes. Colletotrichum acutatum spp. is a major strawberry pathogen, and completely resistant cultivars have not been reported. Moreover, strawberry defense network components and mechanisms remain largely unknown and poorly understood. Assessment of the strawberry response to C. acutatum included a global transcript analysis, and acidic hormones SA and JA measurements were analyzed after challenge with the pathogen. Induction of transcripts corresponding to the SA and JA signaling pathways and key genes controlling major steps within these defense pathways was detected. Accordingly, SA and JA accumulated in strawberry after infection. Contrastingly, induction of several important SA, JA, and oxidative stress-responsive defense genes, including FaPR1-1, FaLOX2, FaJAR1, FaPDF1, and FaGST1, was not detected, which suggests that specific branches in these defense pathways (those leading to FaPR1-2, FaPR2-1, FaPR2-2, FaAOS, FaPR5, and FaPR10) were activated. Our results reveal that specific aspects in SA and JA dependent signaling pathways are activated in strawberry upon interaction with C. acutatum. Certain described defense-associated transcripts related to these two known signaling pathways do not increase in abundance following infection. This finding suggests new insight into a specific putative molecular strategy for defense against this pathogen. PMID:27471515

  7. Partial Activation of SA- and JA-Defensive Pathways in Strawberry upon Colletotrichum acutatum Interaction.

    PubMed

    Amil-Ruiz, Francisco; Garrido-Gala, José; Gadea, José; Blanco-Portales, Rosario; Muñoz-Mérida, Antonio; Trelles, Oswaldo; de Los Santos, Berta; Arroyo, Francisco T; Aguado-Puig, Ana; Romero, Fernando; Mercado, José-Ángel; Pliego-Alfaro, Fernando; Muñoz-Blanco, Juan; Caballero, José L

    2016-01-01

    Understanding the nature of pathogen host interaction may help improve strawberry (Fragaria × ananassa) cultivars. Plant resistance to pathogenic agents usually operates through a complex network of defense mechanisms mediated by a diverse array of signaling molecules. In strawberry, resistance to a variety of pathogens has been reported to be mostly polygenic and quantitatively inherited, making it difficult to associate molecular markers with disease resistance genes. Colletotrichum acutatum spp. is a major strawberry pathogen, and completely resistant cultivars have not been reported. Moreover, strawberry defense network components and mechanisms remain largely unknown and poorly understood. Assessment of the strawberry response to C. acutatum included a global transcript analysis, and acidic hormones SA and JA measurements were analyzed after challenge with the pathogen. Induction of transcripts corresponding to the SA and JA signaling pathways and key genes controlling major steps within these defense pathways was detected. Accordingly, SA and JA accumulated in strawberry after infection. Contrastingly, induction of several important SA, JA, and oxidative stress-responsive defense genes, including FaPR1-1, FaLOX2, FaJAR1, FaPDF1, and FaGST1, was not detected, which suggests that specific branches in these defense pathways (those leading to FaPR1-2, FaPR2-1, FaPR2-2, FaAOS, FaPR5, and FaPR10) were activated. Our results reveal that specific aspects in SA and JA dependent signaling pathways are activated in strawberry upon interaction with C. acutatum. Certain described defense-associated transcripts related to these two known signaling pathways do not increase in abundance following infection. This finding suggests new insight into a specific putative molecular strategy for defense against this pathogen.

  8. 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).

  9. A resolution recognizing Expo 2010 Shanghai China and the USA Pavilion at the Expo.

    THOMAS, 111th Congress

    Sen. Kerry, John F. [D-MA

    2010-05-17

    Senate - 05/25/2010 Placed on Senate Legislative Calendar under General Orders. Calendar No. 409. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  10. 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.

  11. 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...

  12. 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...

  13. 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.

  14. Physiological Characteristics and Production of Folic Acid of Lactobacillus plantarum JA71 Isolated from Jeotgal, a Traditional Korean Fermented Seafood

    PubMed Central

    Lim, Sang-Dong

    2014-01-01

    Folic acid, one of the B group of vitamins, is an essential substance for maintaining the functions of the nervous system, and is also known to decrease the level of homocysteine in plasma. Homocysteine influences the lowering of the cognitive function in humans, and especially in elderly people. In order to determine the strains with a strong capacity to produce folic acid, 190 bacteria were isolated from various kinds of jeotgal and chungkuk-jang. In our test experiment, JA71 was found to contain 9.03μg/mL of folic acid after 24 h of incubation in an MRS broth. This showed that JA71 has the highest folic acid production ability compared to the other lactic acid bacteria that were isolated. JA71 was identified as Lactobacillus plantarum by the result of API carbohydrate fermentation pattern and 16s rDNA sequence. JA71 was investigated for its physiological characteristics. The optimum growth temperature of JA71 was 37℃, and the cultures took 12 h to reach pH 4.4. JA71 proved more sensitive to bacitracin when compared with fifteen different antibiotics, and showed most resistance to neomycin and vancomycin. Moreover, it was comparatively tolerant of bile juice and acid, and displayed resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus with restraint rates of 60.4%, 96.7%, and 76.2%, respectively. These results demonstrate that JA71 could be an excellent strain for application to functional products. PMID:26760752

  15. 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

  16. Carbonate acidizing

    SciTech Connect

    Daccord, G.; Touboul, E.; Lenormand, R.

    1989-02-01

    The authors present the first quantitative study and complete model of the wormholing phenomenon, leading to a means of predicting and optimizing carbonate acidizing treatments. Laboratory experiments on a gypsum model system and computer simulations show that for a given geometry, wormholes can be quantified by a unique parameter, their equivalent hydraulic length. The behavior of this quantifying parameter vs. all the system parameters is studied and allows the quantitative prediction of the efficiency of an acidizing treatment. This study highlights the fractal nature of the phenomenon, which is accounted for in the equations, and the strong effect of the sample geometry. Three types of etching can be obtained: compact, wormhole type, or homogeneous. The optimum conditions for achieving the best skin decrease correspond to the creation of wormholes and can then be defined in terms of fluid reactivity and injection rate.

  17. 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.

  18. 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.

  19. 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.

  20. 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/

  1. Disclinations in Carbon-Carbon Composites.

    DTIC Science & Technology

    1983-09-01

    carbon-carbon composite has been investigated. Shear cracks were introduced in a two-directional carbon-carbon composite by short-beam shear testing ...graphitization at 2700°C. The final bulk density was 1.95 g/cc. Specimens of this composite, oriented parallel to each fiber direction, were tested in short...symposium were as follows: - New Processing raw materials preparation mesophase control manufacturing methods m characterization and design - New

  2. New Enhanced Artificial Bee Colony (JA-ABC5) Algorithm with Application for Reactive Power Optimization

    PubMed Central

    2015-01-01

    The standard artificial bee colony (ABC) algorithm involves exploration and exploitation processes which need to be balanced for enhanced performance. This paper proposes a new modified ABC algorithm named JA-ABC5 to enhance convergence speed and improve the ability to reach the global optimum by balancing exploration and exploitation processes. New stages have been proposed at the earlier stages of the algorithm to increase the exploitation process. Besides that, modified mutation equations have also been introduced in the employed and onlooker-bees phases to balance the two processes. The performance of JA-ABC5 has been analyzed on 27 commonly used benchmark functions and tested to optimize the reactive power optimization problem. The performance results have clearly shown that the newly proposed algorithm has outperformed other compared algorithms in terms of convergence speed and global optimum achievement. PMID:25879054

  3. 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.

  4. 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.

  5. Resistance of Fusarium poae in Arabidopsis leaves requires mainly functional JA and ET signaling pathways.

    PubMed

    Dinolfo, María Inés; Castañares, Eliana; Stenglein, Sebastián A

    2017-10-01

    Fusarium poae has been considered as a minor species among those that cause the FHB disease but in recent years several researchers have documented a high frequency of occurrence in several crops. We evaluated the ability of F. poae to produce symptoms in A. thaliana leaves. Moreover, we analyzed the defense of A. thaliana against F. poae using SA, JA, and ET mutants and we monitored the expression level of genes involved in the main signaling pathways related to plant defense. Symptoms were observed in the inoculated leaves demonstrating the ability of F. poae to infect A. thaliana leaves. Moreover, the npr1-1 mutants presented low symptoms compared to Col-0, etr2-1, and coi1-1 and that the coi1-1 mutant was the most susceptible genotypes followed by etr2-1 genotypes. The RT-PCR revealed that PDF1.2, CHI/PR3, and ERF1, three important JA-ET responsive genes and NPR1 and PR1, which are regulated by SA signaling, were expressed upon F. poae inoculation. Our results suggest that JA and ET could play a key role in Arabidopsis leaves defense against F. poae representing the first evaluation of the response of the main A. thaliana phytohormones involved in plant defense in the presence of F. poae. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  6. Biosynthesis of silver and zinc oxide nanoparticles using Pichia fermentans JA2 and their antimicrobial property

    NASA Astrophysics Data System (ADS)

    Chauhan, Ritika; Reddy, Arpita; Abraham, Jayanthi

    2015-01-01

    The development of eco-friendly alternative to chemical synthesis of metal nanoparticles is of great challenge among researchers. The present study aimed to investigate the biological synthesis, characterization, antimicrobial study and synergistic effect of silver and zinc oxide nanoparticles against clinical pathogens using Pichia fermentans JA2. The extracellular biosynthesis of silver and zinc oxide nanoparticles was investigated using Pichia fermentans JA2 isolated from spoiled fruit pulp bought in Vellore local market. The crystalline and stable metallic nanoparticles were characterized evolving several analytical techniques including UV-visible spectrophotometer, X-ray diffraction pattern analysis and FE-scanning electron microscope with EDX-analysis. The biosynthesized metallic nanoparticles were tested for their antimicrobial property against medically important Gram positive, Gram negative and fungal pathogenic microorganisms. Furthermore, the biosynthesized nanoparticles were also evaluated for their increased antimicrobial activities with various commercially available antibiotics against clinical pathogens. The biosynthesized silver nanoparticles inhibited most of the Gram negative clinical pathogens, whereas zinc oxide nanoparticles were able to inhibit only Pseudomonas aeruginosa. The combined effect of standard antibiotic disc and biosynthesized metallic nanoparticles enhanced the inhibitory effect against clinical pathogens. The biological synthesis of silver and zinc oxide nanoparticles is a novel and cost-effective approach over harmful chemical synthesis techniques. The metallic nanoparticles synthesized using Pichia fermentans JA2 possess potent inhibitory effect that offers valuable contribution to pharmaceutical associations.

  7. 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.

  8. 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.

  9. 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.

  10. From carbon nanotubes to carbon atomic chains

    NASA Astrophysics Data System (ADS)

    Casillas García, Gilberto; Zhang, Weijia; José-Yacamán, Miguel

    2010-10-01

    Carbyne is a linear allotrope of carbon. It is formed by a linear arrangement of carbon atoms with sp-hybridization. We present a reliable and reproducible experiment to obtain these carbon atomic chains using few-layer-graphene (FLG) sheets and a HRTEM. First the FLG sheets were synthesized from worm-like exfoliated graphite and then drop-casted on a lacey-carbon copper grid. Once in the TEM, two holes are opened near each other in a FLG sheet by focusing the electron beam into a small spot. Due to the radiation, the carbon atoms rearrange themselves between the two holes and form carbon fibers. The beam is concentrated on the carbon fibers in order excite the atoms and induce a tension until multi wall carbon nanotube (MWCNT) is formed. As the radiation continues the MWCNT breaks down until there is only a single wall carbon nanotube (SWCNT). Then, when the SWCNT breaks, an atomic carbon chain is formed, lasts for several seconds under the radiation and finally breaks. This demonstrates the stability of this carbon structure.

  11. High-Rate Mechanical Properties of JA2 Propellant at Temperatures from -50 to 80 deg C

    DTIC Science & Technology

    2015-07-01

    Proving Ground (MD): Army Research Laboratory (US); 2005 Jul. Report No.: ARL-TR-3546. 11. Hoffman HJ. Uniaxial compressive gun propellant test. In: Solid ...ARL-MR-0894 ● JULY 2015 US Army Research Laboratory High-Rate Mechanical Properties of JA2 Propellant at Temperatures from –50...Research Laboratory High-Rate Mechanical Properties of JA2 Propellant at Temperatures from –50 to 80 °C by Stephen L Howard, Michael G Leadore

  12. 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.

  13. The crosstalk between Target of Rapamycin (TOR) and Jasmonic Acid (JA) signaling existing in Arabidopsis and cotton

    PubMed Central

    Song, Yun; Zhao, Ge; Zhang, Xueyan; Li, Linxuan; Xiong, Fangjie; Zhuo, Fengping; Zhang, Chaojun; Yang, Zuoren; Datla, Raju; Ren, Maozhi; Li, Fuguang

    2017-01-01

    Target of rapamycin (TOR) acts as an important regulator of cell growth, development and stress responses in most examined diploid eukaryotes. However, little is known about TOR in tetraploid species such as cotton. Here, we show that TORC1-S6K-RPS6, the major signaling components, are conserved and further expanded in cotton genome. Though the cotton seedlings are insensitive to rapamycin, AZD8055, the second-generation inhibitor of TOR, can significantly suppress the growth in cotton. Global transcriptome analysis revealed that genes associated with jasmonic acid (JA) biosynthesis and transduction were significantly altered in AZD8055 treated cotton seedlings, suggesting the potential crosstalk between TOR and JA signaling. Pharmacological and genetic approaches have been employed to get further insights into the molecular mechanism of the crosstalk between TOR and JA. Combination of AZD8055 with methyl jasmonate can synergistically inhibit cotton growth, and additionally JA levels were significantly increased when cotton seedlings were subjected to AZD8055. JA biosynthetic and signaling mutants including jar1, coi1-2 and myc2-2 displayed TOR inhibitor-resistant phenotypes, whereas COI1 overexpression transgenic lines and jaz10 exhibited sensitivity to AZD8055. Consistently, cotton JAZ can partially rescue TOR-suppressed phenotypes in Arabidopsis. These evidences revealed that the crosstalk between TOR and JA pathway operates in cotton and Arabidopsis. PMID:28374843

  14. The crosstalk between Target of Rapamycin (TOR) and Jasmonic Acid (JA) signaling existing in Arabidopsis and cotton.

    PubMed

    Song, Yun; Zhao, Ge; Zhang, Xueyan; Li, Linxuan; Xiong, Fangjie; Zhuo, Fengping; Zhang, Chaojun; Yang, Zuoren; Datla, Raju; Ren, Maozhi; Li, Fuguang

    2017-04-04

    Target of rapamycin (TOR) acts as an important regulator of cell growth, development and stress responses in most examined diploid eukaryotes. However, little is known about TOR in tetraploid species such as cotton. Here, we show that TORC1-S6K-RPS6, the major signaling components, are conserved and further expanded in cotton genome. Though the cotton seedlings are insensitive to rapamycin, AZD8055, the second-generation inhibitor of TOR, can significantly suppress the growth in cotton. Global transcriptome analysis revealed that genes associated with jasmonic acid (JA) biosynthesis and transduction were significantly altered in AZD8055 treated cotton seedlings, suggesting the potential crosstalk between TOR and JA signaling. Pharmacological and genetic approaches have been employed to get further insights into the molecular mechanism of the crosstalk between TOR and JA. Combination of AZD8055 with methyl jasmonate can synergistically inhibit cotton growth, and additionally JA levels were significantly increased when cotton seedlings were subjected to AZD8055. JA biosynthetic and signaling mutants including jar1, coi1-2 and myc2-2 displayed TOR inhibitor-resistant phenotypes, whereas COI1 overexpression transgenic lines and jaz10 exhibited sensitivity to AZD8055. Consistently, cotton JAZ can partially rescue TOR-suppressed phenotypes in Arabidopsis. These evidences revealed that the crosstalk between TOR and JA pathway operates in cotton and Arabidopsis.

  15. Differential Expression of Carotenogenic Genes, Associated Changes on Astaxanthin Production and Photosynthesis Features Induced by JA in H. pluvialis

    PubMed Central

    Zhang, Xiaowen; Xu, Dong; Zhao, Yuefeng; Wang, Yitao; Lv, Hongxin; Liming Yang; Chen, Lingling; Ye, Naihao

    2012-01-01

    Haematococcus pluvialis is an organism that under certain conditions can produce astaxanthin, an economically important carotenoid. In this study, the transcriptional expression patterns of eight carotenogenic genes of H. pluvialis in response to jasmonic acid (JA) were evaluated using real-time PCR. Astaxanthin accumulation action and photosynthesis flourescence were monitored at the same time. The results showed all eight genes exhibited higher transcriptional expression significantly under JA treatments. JA25 (25 mg/L) induction had greater effect (>10-fold up-regulation) on the transcriptional expression of pds, crtR-B and lyc than on ipi-1, ipi-2, psy, bkt2, and crtO. JA50 (50 mg/L) treatment had greater impact on the transcriptional expression of ipi-1, ipi-2, psy, crtR-B and crtO than on pds, lyc and bkt2. Astaxanthin biosynthesis in the presence of JA appeared to be up-regulated mainly by psy, pds, crtR-B, lyc, bkt2 and crtO at the transcriptional level and ipi-1, ipi-2 at both transcriptional and post-transcriptional levels. Under JA induction, the photosynthetic efficiency [Y (II)] and the maximum quantum efficiency of PS II (Fv/Fm) decreased significantly, but the non-photochemical quenching of chlorophyll fluorescence (NPQ) increased drastically with the accumulation of astaxanthin. PMID:22870309

  16. 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.

  17. 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.

  18. Acetylenic carbon allotrope

    DOEpatents

    Lagow, R.J.

    1998-02-10

    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. 17 figs.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Carbon/Carbon extendible Nozzles

    NASA Astrophysics Data System (ADS)

    Lacoste, M.; Lacombe, A.; Joyez, P.; Ellis, R. A.; Lee, J. C.; Payne, F. M.

    2002-03-01

    For many years, SEP has developed C-C composite materials to lighten architectures of propulsion systems, thanks to their high specific mechanical properties kept up to about 2500°C. The 3D carbon reinforcement the so-called Novoltex ® has emerged, and today more than 150 tons per year of C-C is produced by SEP using it. The advent of these thermostructural composite materials have blazed a trail for innovative solutions applicable to the extreme operating conditions of large rocket engines, to improve their performances. The extendible nozzle concept has been developed to optimize the expansion ratio with regard to size restriction required particularly for the upper stages of launchers. The first two tests of a SEP extendible nozzle extension were carried out in 1979, one on a ring design and one on a panel design. Today, nearly all possible configurations have been tested, from the simple scenario of extending a ring from a fixed nozzle prior to ignition, to the most complex one: nozzle deployment while the motor is operating and when the nozzle is being vectored. In August 1995, Pratt & Whitney have entrusted SEP with the development of the C-C exit cone dedicated to the RL10 B-2 cryotechnic engine, propulsion system of the DELTA III upper stage. One year later, in August 1996, SEP delivered the first development item which is currently under testing. When the entire C-C nozzle is attached to the RL10 B-2 engine and deployed, the nozzle diameter increases from 1.1 to 2.1 m and translates to 2.5 m in length, providing an expansion ratio of 285:1 and 30 s of specific impulse increase to the engine. Finally, the paper will describe the design and manufacturing of this huge exit cone and will report the latest test results.

  5. 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

  6. Methyl jasmonate elicits rapid changes in carbon and nitrogen dynamics in tomato.

    PubMed

    Gómez, Sara; Ferrieri, Richard A; Schueller, Michael; Orians, Colin M

    2010-11-01

    • Evidence is emerging to support the notion that in response to herbivory, plants undergo changes in their primary metabolism and are able to fine-tune the allocation of new and existing resources and temporarily direct them to storage organs. • We hypothesized that simulated herbivory increases the export of resources out of the affected tissues and increases allocation to roots. We used short-lived radioisotopes to study in vivo the dynamics of newly incorporated (11)CO(2) and (13)NH(3). Methyl jasmonate (MeJA), a known defense elicitor, was applied to the foliage of tomato plants and 4 h later we monitored leaf uptake, export and whole-plant allocation of [(11)C]photosynthate and [(13)N]amino acids. • There was a marginally significant decrease in the fixation of (11)CO(2), and an increase in the export of newly acquired carbon and nitrogen out of MeJA-treated leaves. The proportion of nitrogen allocated to roots increased, whereas the proportion of carbon did not change. • These results are in agreement with our hypotheses, showing a change in the allocation of resources after treatment with MeJA; this may reduce the chance of resources being lost to herbivores and act as a buffer to biotic stress by increasing the potential for plant regrowth and survival after the attack. © The Authors (2010). Journal compilation © New Phytologist Trust (2010).

  7. 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.

  8. Accelerating Mineral Carbonation Using Carbonic Anhydrase.

    PubMed

    Power, Ian M; Harrison, Anna L; Dipple, Gregory M

    2016-03-01

    Carbonic anhydrase (CA) enzymes have gained considerable attention for their potential use in carbon dioxide (CO2) capture technologies because they are able to catalyze rapidly the interconversion of aqueous CO2 and bicarbonate. However, there are challenges for widespread implementation including the need to develop mineralization process routes for permanent carbon storage. Mineral carbonation of highly reactive feedstocks may be limited by the supply rate of CO2. This rate limitation can be directly addressed by incorporating enzyme-catalyzed CO2 hydration. This study examined the effects of bovine carbonic anhydrase (BCA) and CO2-rich gas streams on the carbonation rate of brucite [Mg(OH)2], a highly reactive mineral. Alkaline brucite slurries were amended with BCA and supplied with 10% CO2 gas while aqueous chemistry and solids were monitored throughout the experiments (hours to days). In comparison to controls, brucite carbonation using BCA was accelerated by up to 240%. Nesquehonite [MgCO3·3H2O] precipitation limited the accumulation of hydrated CO2 species, apparently preventing BCA from catalyzing the dehydration reaction. Geochemical models reproduce observed reaction progress in all experiments, revealing a linear correlation between CO2 uptake and carbonation rate. Data demonstrates that carbonation in BCA-amended reactors remained limited by CO2 supply, implying further acceleration is possible.

  9. Over-expression of SlJA2 decreased heat tolerance of transgenic tobacco plants via salicylic acid pathway.

    PubMed

    Liu, Zhong-Ming; Yue, Meng-Meng; Yang, Dong-Yue; Zhu, Shao-Bo; Ma, Na-Na; Meng, Qing-Wei

    2017-04-01

    Over-expression of SlJA2 decreased the accumulation of SA, which resulted in significant physiological and gene expression changes in transgenic tobacco plants, leading to the decreased heat tolerance of transgenic tobacco. NAC family, the largest transcription factors in plants, responses to different environmental stimuli. Here, we isolated a typical NAC transcription factor (SlJA2) from tomato and got transgenic tobacco with SlJA2 over-expression. Expression of SlJA2 was induced by heat stress (42 °C), chilling stress (4 °C), drought stress, osmotic stress, abscisic acid, and salicylic acid. Over-expression of SlJA2 decreased the accumulation of salicylic acid by regulating expression of salicylic acid degradation gene under heat stress. Compared to WT plants, stomatal apertures and water loss increased in transgenic plants, and the damage of photosynthetic apparatus and chlorophyll breakdown were more serious in transgenic plants under heat stress. Meanwhile, more H2O2 and O2(·-) were accumulated transgenic plants and proline synthesis was restricted, which resulted in more serious oxidative damage compared to WT. qRT-PCR analysis showed that over-expression of SlJA2 could down-regulate genes involved in reactive oxygen species scavenging, proline biosynthesis, and response to heat stress. All the above results indicated that SlJA2 may be a negative regulator responded to plant's heat tolerance. Thus, this study provides new insight into roles of NAC family member in plant response to abiotic stress.

  10. Priming for JA-dependent defenses using hexanoic acid is an effective mechanism to protect Arabidopsis against B. cinerea.

    PubMed

    Kravchuk, Zhana; Vicedo, Begonya; Flors, Víctor; Camañes, Gemma; González-Bosch, Carmen; García-Agustín, Pilar

    2011-03-01

    Soil drench treatments with hexanoic acid can effectively protect Arabidopsis plants against Botrytis cinerea through a mechanism based on a stronger and faster accumulation of JA-dependent defenses. Plants impaired in ethylene, salicylic acid, abscisic acid or glutathion pathways showed intact protection by hexanoic acid upon B. cinerea infection. Accordingly, no significant changes in the SA marker gene PR-1 in either the SA or ABA hormone balance were observed in the infected and treated plants. In contrast, the JA signaling pathway showed dramatic changes after hexanoic acid treatment, mainly when the pathogen was present. The impaired JA mutants, jin1-2 and jar1, were unable to display hexanoic acid priming against the necrotroph. In addition, hexanoic acid-treated plants infected with B. cinerea showed priming in the expression of the PDF1.2, PR-4 and VSP1 genes implicated in the JA pathways. Moreover, JA and OPDA levels were primed at early stages by hexanoic acid. Treatments also stimulated increased callose accumulation in response to the pathogen. Although callose accumulation has proved an effective IR mechanism against B. cinerea, it is apparently not essential to express hexanoic acid-induced resistance (HxAc-IR) because the mutant pmr4.1 (callose synthesis defective mutant) is protected by treatment. We recently described how hexanoic acid treatments can protect tomato plants against B. cinerea by stimulating ABA-dependent callose deposition and by priming OPDA and JA-Ile production. We clearly demonstrate here that Hx-IR is a dependent plant species, since this acid protects Arabidopsis plants against the same necrotroph by priming JA-dependent defenses without enhancing callose accumulation.

  11. Rice Rab11 is required for JA-mediated defense signaling

    SciTech Connect

    Hong, Min Ji; Lee, Yun mi; Son, Young Sim; Im, Chak Han; Yi, Young Byung; Rim, Yeong Gil; Bahk, Jeong Dong; Heo, Jae Bok

    2013-05-17

    Highlights: •OsRab11 interacts with OsOPR8. •OsOPR8 is localized in the cytosol and peroxisome. •OsRab11 enhances the NADPH consumption by OsOPR8. •Transgenic Arabidopsis overexpressing OsRab11 represents a pathogen-resistant phenotype. -- Abstract: Rab proteins play an essential role in regulating vesicular transport in eukaryotic cells. Previously, we characterized OsRab11, which in concert with OsGAP1 and OsGDI3 regulates vesicular trafficking from the trans-Golgi network (TGN) to the plasma membrane or vacuole. To further elucidate the physiological function of OsRab11 in plants, we performed yeast two-hybrid screens using OsRab11 as bait. OsOPR8 was isolated and shown to interact with OsRab11. A co-immunoprecipitation assay confirmed this interaction. The green fluorescent protein-OsOPR8 fusion product was targeted to the cytoplasm and peroxisomes of protoplasts from Arabidopsis thaliana. OsOPR8 exhibited NADPH-dependent reduction activity when 2-cyclohexen-1-one (CyHE) and 12-oxo-phytodienoic acid (OPDA) were supplied as possible substrates. Interestingly, NADPH oxidation by OsOPR8 was increased when wild-type OsRab11 or the constitutively active form of OsRab11 (Q78L) were included in the reaction mix, but not when the dominant negative form of OsRab11 (S28N) was included. OsRab11 was expressed broadly in plants and both OsRab11 and OsOPR8 were induced by jasmonic acid (JA) and elicitor treatments. Overexpressed OsRab11 transgenic plants showed resistance to pathogens through induced expression of JA-responsive genes. In conclusion, OsRab11 may be required for JA-mediated defense signaling by activating the reducing activity of OsOPR8.

  12. Visualization and Measurement of the Deflagration of Metal-Foil Bounded JA2

    DTIC Science & Technology

    2015-06-01

    ARL‐TR‐7322 ● JUNE 2015          US Army Research Laboratory      Visualization and  Measurement  of the  Deflagration of Metal‐Foil Bounded...Visualization and  Measurement  of the  Deflagration of Metal‐Foil Bounded JA2    John J Ritter and Anthony Canami  Weapons and Materials Research...

  13. 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.

  14. Optimization of non-oxidative carbon-removal techniques by nitrogen-containing plasmas

    NASA Astrophysics Data System (ADS)

    Ferreira, J. A.; Tabarés, F. L.; Tafalla, D.

    2009-06-01

    The continuous control of tritium inventory in ITER calls for the development of new conditioning techniques [G. Federici et al., Nucl. Fus. 41 (2001) 1967]. For carbon plasma-facing components, this implies the removal of the T-rich carbon co-deposits. In the presence of strong oxygen getters, such Be, the use of oxygen-based techniques will be discouraged. In addition, tritiated water generated by these techniques poses extra problems in terms of safety issues [G. Saji, Fus. Eng. Des. 69 (2003) 631; G. Bellanger, J.J. Rameau, Fus. Technol. 32 (1997) 196; T. Hayashi, et al., Fus. Eng. Des. 81 (2006) 1365]. In the present work, oxygen-free (nitrogen and ammonia) glow discharge plasmas for carbon film removal were investigated. The following gas mixtures were fed into a DC glow discharge running in a ˜200 nm carbon film coated chamber. Erosion rate was measured in situ by laser interferometry, RGA (Residual Gas Analysis) and CTAMS (Cryotrapping Assisted Mass Spectrometry) [J.A. Ferreira, F.L. Tabarés, J. Vac. Sci. Technol. A25(2) (2007) 246] were used for the characterization of the reaction products. Very high erosion rates (similar to those obtained in helium-oxygen glow discharge [J.A. Ferreira et al., J. Nucl. Mater. 363-365 (2007) 252]) were recorded for ammonia glow discharge.

  15. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics.

    PubMed

    Meldau, Stefan; Ullman-Zeunert, Lynn; Govind, Geetha; Bartram, Stefan; Baldwin, Ian T

    2012-11-13

    Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA)-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs), salicylic acid (SA)-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK) and WIPK (irWIPK) benefits the growth and fitness of plants competiting with wild type (WT) plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3) levels. As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels resulted from increased nitrogen or CO

  16. MAPK-dependent JA and SA signalling in Nicotiana attenuata affects plant growth and fitness during competition with conspecifics

    PubMed Central

    2012-01-01

    Background Induced defense responses to herbivores are generally believed to have evolved as cost-saving strategies that defer the fitness costs of defense metabolism until these defenses are needed. The fitness costs of jasmonate (JA)-mediated defenses have been well documented. Those of the early signaling units mediating induced resistance to herbivores have yet to be examined. Early signaling components that mediate herbivore-induced defense responses in Nicotiana attenuata, have been well characterized and here we examine their growth and fitness costs during competition with conspecifics. Two mitogen-activated protein kinases (MAPKs), salicylic acid (SA)-induced protein kinase (SIPK) and wound-induced protein kinase (WIPK) are rapidly activated after perception of herbivory and both kinases regulate herbivory-induced JA levels and JA-mediated defense metabolite accumulations. Since JA-induced defenses result in resource-based trade-offs that compromise plant productivity, we evaluated if silencing SIPK (irSIPK) and WIPK (irWIPK) benefits the growth and fitness of plants competiting with wild type (WT) plants, as has been shown for plants silenced in JA-signaling by the reduction of Lipoxygenase 3 (LOX3) levels. Results As expected, irWIPK and LOX3-silenced plants out-performed their competing WT plants. Surprisingly, irSIPK plants, which have the largest reductions in JA signaling, did not. Phytohormone profiling of leaves revealed that irSIPK plants accumulated higher levels of SA compared to WT. To test the hypothesis that these high levels of SA, and their presumed associated fitness costs of pathogen associated defenses in irSIPK plants had nullified the JA-deficiency-mediated growth benefits in these plants, we genetically reduced SA levels in irSIPK plants. Reducing SA levels partially recovered the biomass and fitness deficits of irSIPK plants. We also evaluated whether the increased fitness of plants with reduced SA or JA levels resulted from

  17. 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.

  18. 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.

  19. 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.

  20. OsJAR1 is required for JA-regulated floret opening and anther dehiscence in rice.

    PubMed

    Xiao, Yuguo; Chen, Yi; Charnikhova, Tatsiana; Mulder, Patrick P J; Heijmans, Jeroen; Hoogenboom, Angela; Agalou, Adamantia; Michel, Corinne; Morel, Jean-Benoit; Dreni, Ludovico; Kater, Martin M; Bouwmeester, Harro; Wang, Mei; Zhu, Zhen; Ouwerkerk, Pieter B F

    2014-09-01

    Jasmonates are important phytohormones regulating reproductive development. We used two recessive rice Tos17 alleles of OsJAR1, osjar1-2 and osjar1-3, to study the biological function of jasmonates in rice anthesis. The florets of both osjar1 alleles stayed open during anthesis because the lodicules, which control flower opening in rice, were not withering on time. Furthermore, dehiscence of the anthers filled with viable pollen, was impaired, resulting in lower fertility. In situ hybridization and promoter GUS transgenic analysis confirmed OsJAR1 expression in these floral tissues. Flower opening induced by exogenous applied methyl jasmonate was impaired in osjar1 plants and was restored in a complementation experiment with transgenics expressing a wild type copy of OsJAR1 controlled by a rice actin promoter. Biochemical analysis showed that OsJAR1 encoded an enzyme conjugating jasmonic acid (JA) to at least Ile, Leu, Met, Phe, Trp and Val and both osjar1 alleles had substantial reduction in content of JA-Ile, JA-Leu and JA-Val in florets. We conclude that OsJAR1 is a JA-amino acid synthetase that is required for optimal flower opening and closing and anther dehiscence in rice.

  1. The tomato res mutant which accumulates JA in roots in non-stressed conditions restores cell structure alterations under salinity.

    PubMed

    Garcia-Abellan, José O; Fernandez-Garcia, Nieves; Lopez-Berenguer, Carmen; Egea, Isabel; Flores, Francisco B; Angosto, Trinidad; Capel, Juan; Lozano, Rafael; Pineda, Benito; Moreno, Vicente; Olmos, Enrique; Bolarin, Maria C

    2015-11-01

    Jasmonic acid (JA) regulates a wide spectrum of plant biological processes, from plant development to stress defense responses. The role of JA in plant response to salt stress is scarcely known, and even less known is the specific response in root, the main plant organ responsible for ionic uptake and transport to the shoot. Here we report the characterization of the first tomato (Solanum lycopersicum) mutant, named res (restored cell structure by salinity), that accumulates JA in roots prior to exposure to stress. The res tomato mutant presented remarkable growth inhibition and displayed important morphological alterations and cellular disorganization in roots and leaves under control conditions, while these alterations disappeared when the res mutant plants were grown under salt stress. Reciprocal grafting between res and wild type (WT) (tomato cv. Moneymaker) indicated that the main organ responsible for the development of alterations was the root. The JA-signaling pathway is activated in res roots prior to stress, with transcripts levels being even higher in control condition than in salinity. Future studies on this mutant will provide significant advances in the knowledge of JA role in root in salt-stress tolerance response, as well as in the energy trade-off between plant growth and response to stress.

  2. 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.

  3. Chapter 7: Managing Carbon

    Treesearch

    Kenneth E. Skog; Duncan C. McKinley; Richard A. Birdsey; Sarah J. Hines; Christopher W. Woodall; Elizabeth D. Reinhardt; James M. Vose

    2014-01-01

    Storing carbon (C) and offsetting carbon dioxide (CO2) emissions with the use of wood for energy, both of which slow emissions of CO2 into the atmosphere, present significant challenges for forest management (IPCC 2001).

  4. 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.

  5. 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...

  6. 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.

  7. 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...

  8. 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.

  9. 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.

  10. 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.

  11. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Charles Miller talks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  12. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Panelists are seen during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  13. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Ralph Basilio talks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  14. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Eric Ianson speaks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  15. 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.

  16. Draft genome sequence of Rhodomicrobium udaipurense JA643T with special reference to hopanoid biosynthesis.

    PubMed

    Tushar, L; Sasikala, Ch; Ramana, Ch V

    2014-12-01

    Hopanoids are present in vast amounts as integral components of bacteria and plants with their primary function to strengthen rigidity of the plasma membrane. To establish their roles more precisely, we conducted sequencing of the whole genome of Rhodomicrobium udaipurense JA643(T) isolated from a fresh water stream of Udaipur in Himachal Pradesh, India, by using the Illumina HiSeq pair end chemistry of 2 × 100 bp platform. Determined genome showed a high degree of similarity to the genome of R. vannielii ATCC17100(T) and the 13.7 million reads generated a sequence of 3,649,277 bp possessing 3,611 putative genes. The genomic data were subsequently investigated with respect to genes involved in various features. The machinery required for the degradation of aromatic compounds and resistance to solvents as well as all that required for photosynthesis are present in this organism. Also, through extensive functional annotation, 18 genes involved in the biosynthesis of hopanoids are predicted, namely those responsible for the synthesis of diploptene, diplopterol, adenosylhopane, ribosylhopane, aminobacteriohopanetriol, glycosyl group containing hopanoids and unsaturated hopanoids. The hopanoid biosynthetic pathway was then inferred based on the genes identified and through experimental validation of individual hopanoid molecules. The genome data of R. udaipurense JA643(T) will be useful in understanding the functional features of hopanoids in this bacterium.

  17. Early dust formation and a massive progenitor for SN 2011ja?

    NASA Astrophysics Data System (ADS)

    Andrews, J. E.; Krafton, Kelsie M.; Clayton, Geoffrey C.; Montiel, E.; Wesson, R.; Sugerman, Ben E. K.; Barlow, M. J.; Matsuura, M.; Drass, H.

    2016-04-01

    SN 2011ja was a bright (I = -18.3) Type II supernova occurring in the nearby edge on spiral galaxy NGC 4945. Flat-topped and multipeaked H α and H β spectral emission lines appear between 64 and 84 d post-explosion, indicating interaction with a disc-like circumstellar medium inclined ˜45° from edge-on. After day 84, an increase in the H- and K-band flux along with heavy attenuation of the red wing of the emission lines are strong indications of early dust formation, likely located in the cool dense shell created between the forward shock of the SN ejecta and the reverse shock created as the ejecta plows into the existing circumstellar material. Radiative transfer modelling reveals both ≈1 × 10-5 M⊙ of pre-existing dust located ˜1016.7 cm away and up to ≈6 × 10-4 M⊙ of newly formed dust. Spectral observations after 1.5 yr reveal the possibility that the fading SN is located within a young (3-6 Myr) massive stellar cluster, which when combined with tentative 56Ni mass estimates of 0.2 M⊙ may indicate a massive (≥25 M⊙) progenitor for SN 2011ja.

  18. Kinetics and regulation of lactose transport and metabolism in Kluyveromyces lactis JA6.

    PubMed

    Santos, A M; Silveira, W B; Fietto, L G; Brandão, R L; Castro, I M

    2014-07-01

    Kluyveromyces lactis strains are able to assimilate lactose. They have been used industrially to eliminate this sugar from cheese whey and in other industrial products. In this study, we investigated specific features and the kinetic parameters of the lactose transport system in K. lactis JA6. In lactose grown cells, lactose was transported by a system transport with a half-saturation constant (K s) of 1.49 ± 0.38 mM and a maximum velocity (V max) of 0.96 ± 0.12 mmol. (g dry weight)(-1) h(-1) for lactose. The transport system was constitutive and energy-dependent. Results obtained by different approaches showed that the lactose transport system was regulated by glucose at the transcriptional level and by glucose and other sugars at a post-translational level. In K. lactis JA6, galactose metabolization was under glucose control. These findings indicated that the regulation of lactose-galactose regulon in K. lactis was similar to the regulation of galactose regulon in Saccharomyces cerevisiae.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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…

  4. 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.

  5. 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.

  6. 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…

  7. Orbiting Carbon Observatory Briefing

    NASA Image and Video Library

    2009-01-29

    Anna Michalak, an Orbiting Carbon Observatory science team member from the University of Michigan, Ann Arbor, speaks during a media briefing to discuss the upcoming Orbiting Carbon Observatory mission, the first NASA spacecraft dedicated to studying carbon dioxide, Thursday, Jan. 29, 2009, at NASA Headquarters in Washington. Photo Credit: (NASA/Paul E. Alers)

  8. Acute oral toxicity of JA-2 solid propellant in icr mice. Report for 17 December 1985-17 January 1986

    SciTech Connect

    Morgan, E.W.; Frost, D.F.; Wheller, C.R.; Korte, D.W.

    1989-12-01

    The acute oral toxicity of JA-2 Solid Propellant was determined in male and female ICR mice by using an oral gavage, split-dose method. The MLD was 3774.6 + or - 150.5 mg/kg for male mice and 3528.8 + or - 133.8 mg/kg for female mice. JA-2 produced component, diethyleneglycol dinitrate and nitroglycerin. These signs included tremors, inactivity, depression of reflexes, loss of equilibrium, opisthotonus, and increased respiratory activity. Other clinical signs observed were associated with the general malaise of the animals following dosing and included perianal staining, hunched posture, squinting, and rough coat. Most animals exhibited signs by 2 hours after dosing and either had died or the signs had cleared within 5 days of dosing. According to the classification scheme of Hodge and Sterner, these results place JA-2 in the slightly toxic class.

  9. Acute oral toxicity of ja-2 solid propellant in sprague-dawley rats. Report for 12 November-19 December 1985

    SciTech Connect

    Brown, L.D.; Justus, J.D.; Wheeler, C.R.; Korte, D.W.

    1989-12-01

    The acute oral toxicity of JA-2 Solid Propellant was determined in male and female Sprague-Dawley rats by using an oral gavage split-dose method. The MLD was 3990.6 + or - 349.7 mg/kg for male rats and 2545.9 + or - 421.1 mg/kg for female rats. JA-2 produced clinical signs that were attributed to its nitrate ester components, diethyleneglycol dinitrate and nitroglycerin. These signs included tremors and twitching, cyanosis, and increases in respiratory rate and depth. Other clinical signs observed were associated with the general malaise of the animals following dosing and included hunched posture, rough coat, reddish stains around the eyes and nose, and perianal staining. Most animals exhibited signs by 4 hours after dosing and either had died or the signs had cleared by 96 hours after dosing. According to the classification scheme of Hodge and Sterner, these results place JA-2 in the slightly toxic class.

  10. Global carbon uptake by cement carbonation

    NASA Astrophysics Data System (ADS)

    Davis, S. J.; Xi, F.; Liu, Z.; Ciais, P.; Crawford-Brown, D.; Guan, D.; Pade, C.; Shi, T.; Syddall, M.; Lv, J.; Ji, L.; Bing, L.; Wang, J.; Wei, W.; Yang, K. H.; Lagerblad, B.; Galan, I.; Andrade, C.; Zhang, Y.

    2016-12-01

    Calcination of carbonate rocks during the manufacture of cement produced emissions equivalent to 5% of global fossil CO2 emissions 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 almost no attention in carbon cycle studies. Here, we show carbonation of cement materials over their life cycle represents a large and growing net sink of CO2 (0.10 GtC y-1 in 1998 to 0.25 GtC y-1 in 2013). In total, we estimate that a cumulative amount of 4.5 GtC (2.8-7.5, p=0.05) has been sequestered in carbonating cement materials from 1930 to 2013, offsetting 43% of the process CO2 emissions from production of cement (excluding those from related fossil energy inputs) over the same period. The emissions inventories prepared using IPCC guidelines and used by recent carbon cycle studies are thus missing a substantial carbon sink.

  11. 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.

  12. Transcriptome sequencing and de novo analysis of cytoplasmic male sterility and maintenance in JA-CMS cotton.

    PubMed

    Yang, Peng; Han, Jinfeng; Huang, Jinling

    2014-01-01

    Cytoplasmic male sterility (CMS) is the failure to produce functional pollen, which is inherited maternally. And it is known that anther development is modulated through complicated interactions between nuclear and mitochondrial genes in sporophytic and gametophytic tissues. However, an unbiased transcriptome sequencing analysis of CMS in cotton is currently lacking in the literature. This study compared differentially expressed (DE) genes of floral buds at the sporogenous cells stage (SS) and microsporocyte stage (MS) (the two most important stages for pollen abortion in JA-CMS) between JA-CMS and its fertile maintainer line JB cotton plants, using the Illumina HiSeq 2000 sequencing platform. A total of 709 (1.8%) DE genes including 293 up-regulated and 416 down-regulated genes were identified in JA-CMS line comparing with its maintainer line at the SS stage, and 644 (1.6%) DE genes with 263 up-regulated and 381 down-regulated genes were detected at the MS stage. By comparing the two stages in the same material, there were 8 up-regulated and 9 down-regulated DE genes in JA-CMS line and 29 up-regulated and 9 down-regulated DE genes in JB maintainer line at the MS stage. Quantitative RT-PCR was used to validate 7 randomly selected DE genes. Bioinformatics analysis revealed that genes involved in reduction-oxidation reactions and alpha-linolenic acid metabolism were down-regulated, while genes pertaining to photosynthesis and flavonoid biosynthesis were up-regulated in JA-CMS floral buds compared with their JB counterparts at the SS and/or MS stages. All these four biological processes play important roles in reactive oxygen species (ROS) homeostasis, which may be an important factor contributing to the sterile trait of JA-CMS. Further experiments are warranted to elucidate molecular mechanisms of these genes that lead to CMS.

  13. 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.

  14. 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.

  15. 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.

  16. Electrochemistry of Carbon Dioxide on Carbon Electrodes.

    PubMed

    Yang, Nianjun; Waldvogel, Siegfried R; Jiang, Xin

    2016-01-04

    Carbon electrodes have the advantages of being chemically inert at negative potential ranges in all media and high offset potentials for hydrogen evolution in comparison to metal electrodes, and therefore are the most suitable electrodes for electrochemistry and electrochemical conversion of CO2 into valuable chemicals. Herein we summarize on carbon electrodes the voltammetry, electrochemical and electrocatalytic CO2 reduction, as well as electron synthesis using CO2 and carbon electrodes. The electrocatalytic CO2 reduction using carbocatalyts and the future activities about electrochemical CO2 conversion are highlighted.

  17. 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.

  18. The Taste of Carbonation

    PubMed Central

    Chandrashekar, Jayaram; Yarmolinsky, David; von Buchholtz, Lars; Oka, Yuki; Sly, William; Ryba, Nicholas J. P.; Zuker, Charles S.

    2013-01-01

    Summary Carbonated beverages are commonly available and immensely popular, but little is known about the cellular and molecular mechanisms underlying the perception of carbonation in the mouth. In mammals, carbonation elicits both somatosensory and chemosensory responses, including activation of taste neurons. We have now identified the cellular and molecular substrates for the taste of carbonation. By targeted genetic ablation and the silencing of synapses in defined populations of taste receptor cells, we demonstrate that the sour-sensing cells act as the taste sensors for carbonation, and show that carbonic anhydrase 4, a glycosyl-phosphatidyl inositol (GPI)-anchored enzyme, functions as the principal CO2 taste sensor. These studies reveal the basis of the taste of carbonation, and the contribution of taste cells in the orosensory response to CO2. PMID:19833970

  19. The taste of carbonation.

    PubMed

    Chandrashekar, Jayaram; Yarmolinsky, David; von Buchholtz, Lars; Oka, Yuki; Sly, William; Ryba, Nicholas J P; Zuker, Charles S

    2009-10-16

    Carbonated beverages are commonly available and immensely popular, but little is known about the cellular and molecular mechanisms underlying the perception of carbonation in the mouth. In mammals, carbonation elicits both somatosensory and chemosensory responses, including activation of taste neurons. We have identified the cellular and molecular substrates for the taste of carbonation. By targeted genetic ablation and the silencing of synapses in defined populations of taste receptor cells, we demonstrated that the sour-sensing cells act as the taste sensors for carbonation, and showed that carbonic anhydrase 4, a glycosylphosphatidylinositol-anchored enzyme, functions as the principal CO2 taste sensor. Together, these studies reveal the basis of the taste of carbonation as well as the contribution of taste cells in the orosensory response to CO2.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. Banana fruit VQ motif-containing protein5 represses cold-responsive transcription factor MaWRKY26 involved in the regulation of JA biosynthetic genes

    PubMed Central

    Ye, Yu-Jie; Xiao, Yun-Yi; Han, Yan-Chao; Shan, Wei; Fan, Zhong-Qi; Xu, Qun-Gang; Kuang, Jian-Fei; Lu, Wang-Jin; Lakshmanan, Prakash; Chen, Jian-Ye

    2016-01-01

    Most harvested fruits and vegetables are stored at low temperature but many of them are highly sensitive to chilling injury. Jasmonic acid (JA), a plant hormone associated with various stress responses, is known to reduce chilling injury in fruits. However, little is known about the transcriptional regulation of JA biosynthesis in relation to cold response of fruits. Here, we show the involvement of a Group I WRKY transcription factor (TF) from banana fruit, MaWRKY26, in regulating JA biosynthesis. MaWRKY26 was found to be nuclear-localized with transcriptional activation property. MaWRKY26 was induced by cold stress or by methyl jasmonate (MeJA), which enhances cold tolerance in banana fruit. More importantly, MaWRKY26 transactivated JA biosynthetic genes MaLOX2, MaAOS3 and MaOPR3 via binding to their promoters. Further, MaWRKY26 physically interacted with a VQ motif-containing protein MaVQ5, and the interaction attenuated MaWRKY26-induced transactivation of JA biosynthetic genes. These results strongly suggest that MaVQ5 might act as a repressor of MaWRKY26 in activating JA biosynthesis. Taken together, our findings provide new insights into the transcriptional regulation of JA biosynthesis in response to cold stress and a better understanding of the molecular aspects of chilling injury in banana fruit. PMID:27004441

  5. HiJaK: the high-resolution J, H and K spectrometer

    NASA Astrophysics Data System (ADS)

    Muirhead, Philip S.; Hall, Zachary J.; Veyette, Mark J.

    2014-08-01

    We present the science drivers, design requirements and a preliminary design for a high-resolution, broad- bandwidth, slit-fed cross-dispersed near-infrared spectrometer for 5-meter-class telescopes. Our concept, called the High-Resolution J, H and K Spectrometer, or HiJaK, utilizes an R6 echelle in a white-pupil design to achieve high resolution in a compact configuration with a 2048 x 2048 pixel infrared detector. We present a preliminary ray-traced optical design matched to the new 4.3-meter Discovery Channel Telescope in Happy Jack, Arizona. We also discuss mechanical and cryogenic options to house our optical design.

  6. 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).

  7. 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).

  8. High Temperature Induces Expression of Tobacco Transcription Factor NtMYC2a to Regulate Nicotine and JA Biosynthesis

    PubMed Central

    Yang, Liming; Li, Junying; Ji, Jianhui; Li, Ping; Yu, Liangliang; Abd_Allah, Elsayed F.; Luo, Yuming; Hu, Liwei; Hu, Xiangyang

    2016-01-01

    Environmental stress elevates the level of jasmonic acid (JA) and activates the biosynthesis of nicotine and related pyridine alkaloids in tobacco (Nicotiana tabacum L.) by up-regulating the expression of putrescine N-methyltransferase 1 (NtPMT1), which encodes a putrescine N-methyl transferase that catalyzes nicotine formation. The JA signal suppressor JASMONATE ZIM DOMAIN 1 (NtJAZ1) and its target protein, NtMYC2a, also regulate nicotine biosynthesis; however, how these proteins interact to regulate abiotic-induced nicotine biosynthesis is poorly understood. In this study, we found that high-temperature (HT) treatment activated transcription of NtMYC2a, which subsequently stimulated the transcription of genes associated with JA biosynthesis, including Lipoxygenase (LOX), Allene oxide synthase (AOS), Allene oxide cyclase (AOC), and 12-oxophytodienodate reductase (OPR). Overexpression of NtMYC2a increased nicotine biosynthesis by enhancing its binding to the promoter of NtPMT1. Overexpression of either NtJAZ1 or proteasome-resistant NtJAZ1ΔC suppressed nicotine production under normal conditions, but overexpression only of the former resulted in low levels of nicotine under HT treatment. These data suggest that HT induces NtMYC2a accumulation through increased transcription to activate nicotine synthesis; meanwhile, HT-induced NtMYC2a can activate JA synthesis to promote additional NtMYC2a activity by degrading NtJAZ1 at the post-transcriptional level. PMID:27833561

  9. 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.

  10. 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.

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. Smooth-Surfaced Carbon/Carbon Reflector Panels

    NASA Technical Reports Server (NTRS)

    Schmitigal, Wesley P.; Jacoy, Paul J.; Porter, Christopher C.; Hickey, Gregory S.

    1992-01-01

    Surface-densification technique integral to fabrication of reflective, lightweight, low-outgassing radio-antenna-reflector panels including carbon/carbon surface laminates supported by carbon/carbon core structures. Densification prevents "print-through" of carbon fibers on surface. When properly densified, surface polished to smooth finish.

  17. Forests and carbon storage

    Treesearch

    Michael G. Ryan

    2008-01-01

    Forests store much carbon and their growth can be a carbon sink if disturbance or harvesting has killed or removed trees or if trees that can now regrow are planted where they did not historically occur. Forests and long-lived wood products currently offset 310 million metric tons of U.S. fossil fuel emissions of carbon--20 percent of the total (Pacala et al. 2007)....

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. Nanoindentation of Carbon Nanostructures.

    PubMed

    Kumar, Dinesh; Singh, Karamjit; Verma, Veena; Bhatti, H S

    2016-06-01

    In the present research paper carbon nanostructures viz. single walled carbon nanotubes, multi-walled carbon nanotubes, single walled carbon nanohorns and graphene nanoplatelets have been synthesized by CVD technique, hydrothermal method, DC arc discharge method in liquid nitrogen and microwave technique respectively. After synthesis 5 mm thick pallets of given nanomaterial are prepared by making a paste in isopropyl alcohol and using polyvinylidene difluoride as a binder and then these pallets were used for nanoindentation measurements. Hardness, reduced modulus, stiffness, contact height and contact area have been measured using nanoindenter.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. Carbon/Carbon Panels Cooled By Heat Pipes

    NASA Technical Reports Server (NTRS)

    Camarda, Charles J.; Ransone, Philip O.

    1989-01-01

    Durable and reusable high-temperature carbon/carbon heat-pipe structure operates at temperatures above 3,000 degree F (1,649 degree C) in vacuum or inert environment and up to 2,800 degree F (1,537 degree C) in oxidizing environment. New concept combines high-temperature heat-pipe and carbon/carbon technologies to extend both thermal structural capabilities of refractory-metal heat pipes and maximum heat-flux capability of carbon/carbon structures. Uses refractory-metal heat pipes embedded within carbon/carbon structure. Walls of heat pipes thin and contain working fluid (lithium or sodium) of heat pipe. Carbon/carbon acts as primary load-carrying part of structure. Heat pipes help to eliminate local hotspots and associated thermal gradients and stresses and to reduce peak surface temperatures of carbon/carbon to levels within capability of oxidation-resisting system.

  14. 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.

  15. 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,…

  16. 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.

  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 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.)…

  19. 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.

  20. 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)

  1. 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.

  2. 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 ...

  3. 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.)…

  4. 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.

  5. 1992 Carbon emissions data

    SciTech Connect

    1995-12-31

    This article reports on the global total of carbon dioxide emissions from fossil-fuel burning and cement manufacture in 1992. The total estimate of 6097 million metric tons of carbon is essentially the same for 1990 and down slightly from 1991, but 7 of 9 geographical regions had increases.

  6. 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)

  7. Photoinduced antiviral carbon nanohorns

    NASA Astrophysics Data System (ADS)

    Miyako, Eijiro; Nagata, Hideya; Hirano, Ken; Sakamoto, Kotaro; Makita, Yoji; Nakayama, Ken-ichi; Hirotsu, Takahiro

    2008-02-01

    Nanocarbons, such as carbon nanohorns (CNH) and carbon nanotubes, are materials of interest in many fields of science and technology because of their remarkable physical properties. We report here a novel approach for using NIR laser-driven CNH as an antiviral agent. NIR laser-driven functional CNH complexes could open the way to a new range of antiviral materials.

  8. 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.

  9. 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.

  10. 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.

  11. 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 ...

  12. 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,…

  13. Occator Crater and Carbonates

    NASA Image and Video Library

    2016-06-29

    The inset perspective view from NASA Dawn space of Ceres bright spot Occator Crator is overlaid with data concerning the composition. Red signifies a high abundance of carbonates, while gray indicates a low carbonate abundance. http://photojournal.jpl.nasa.gov/catalog/PIA20694

  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. 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%.

  16. Overexpression of OsMYC2 Results in the Up-Regulation of Early JA-Rresponsive Genes and Bacterial Blight Resistance in Rice.

    PubMed

    Uji, Yuya; Taniguchi, Shiduku; Tamaoki, Daisuke; Shishido, Hodaka; Akimitsu, Kazuya; Gomi, Kenji

    2016-09-01

    JASMONATE ZIM-domain (JAZ) proteins act as transcriptional repressors of jasmonic acid (JA) responses and play a crucial role in the regulation of host immunity in plants. Here, we report that OsMYC2, a JAZ-interacting transcription factor in rice (Oryza sativa L.), plays an important role in the resistance response against rice bacterial blight, which is one of the most serious diseases in rice, caused by Xanthomonas oryzae pv. oryzae (Xoo). The results showed that OsMYC2 interacted with some OsJAZ proteins in a JAZ-interacting domain (JID)-dependent manner. The up-regulation of OsMYC2 in response to JA was regulated by OsJAZ8. Transgenic rice plants overexpressing OsMYC2 exhibited a JA-hypersensitive phenotype and were more resistant to Xoo. A large-scale microarray analysis revealed that OsMYC2 up-regulated OsJAZ10 as well as many other defense-related genes. OsMYC2 selectively bound to the G-box-like motif of the OsJAZ10 promoter in vivo and regulated the expression of early JA-responsive genes, but not of late JA-responsive genes. The nuclear localization of OsMYC2 depended on a nuclear localization signal within JID. Overall, we conclude that OsMYC2 acts as a positive regulator of early JA signals in the JA-induced resistance against Xoo in rice.

  17. bHLH003, bHLH013 and bHLH017 Are New Targets of JAZ Repressors Negatively Regulating JA Responses

    PubMed Central

    Fonseca, Sandra; Fernández-Calvo, Patricia; Fernández, Guillermo M.; Díez-Díaz, Monica; Gimenez-Ibanez, Selena; López-Vidriero, Irene; Godoy, Marta; Fernández-Barbero, Gemma; Van Leene, Jelle; De Jaeger, Geert; Franco-Zorrilla, José Manuel; Solano, Roberto

    2014-01-01

    Cell reprogramming in response to jasmonates requires a tight control of transcription that is achieved by the activity of JA-related transcription factors (TFs). Among them, MYC2, MYC3 and MYC4 have been described as activators of JA responses. Here we characterized the function of bHLH003, bHLH013 and bHLH017 that conform a phylogenetic clade closely related to MYC2, MYC3 and MYC4. We found that these bHLHs form homo- and heterodimers and also interact with JAZ repressors in vitro and in vivo. Phenotypic analysis of JA-regulated processes, including root and rosette growth, anthocyanin accumulation, chlorophyll loss and resistance to Pseudomonas syringae, on mutants and overexpression lines, suggested that these bHLHs are repressors of JA responses. bHLH003, bHLH013 and bHLH017 are mainly nuclear proteins and bind DNA with similar specificity to that of MYC2, MYC3 and MYC4, but lack a conserved activation domain, suggesting that repression is achieved by competition for the same cis-regulatory elements. Moreover, expression of bHLH017 is induced by JA and depends on MYC2, suggesting a negative feed-back regulation of the activity of positive JA-related TFs. Our results suggest that the competition between positive and negative TFs determines the output of JA-dependent transcriptional activation. PMID:24465948

  18. JA, a new type of polyunsaturated fatty acid isolated from Juglans mandshurica Maxim, limits the survival and induces apoptosis of heptocarcinoma cells.

    PubMed

    Gao, Xiu-Li; Lin, Hua; Zhao, Wei; Hou, Ya-Qin; Bao, Yong-Li; Song, Zhen-Bo; Sun, Lu-Guo; Tian, Shang-Yi; Liu, Biao; Li, Yu-Xin

    2016-03-01

    Juglans mandshurica Maxim (Juglandaceae) is a famous folk medicine for cancer treatment and some natural compounds isolated from it have been studied extensively. Previously we isolated a type of ω-9 polyunsaturated fatty acid (JA) from the bark of J. mandshurica, however little is known about its activity and the underlying mechanisms. In this study, we studied anti-tumor activity of JA on several human cancer cell lines. Results showed that JA is cytotoxic to HepG2, MDA-MB-231, SGC-7901, A549 and Huh7 cells at a concentration exerting minimal toxic effects on L02 cells. The selective toxicity of JA was better than other classical anti-cancer drugs. Further investigation indicated that JA could induce cell apoptosis, characterized by chromatin condensation, DNA fragmentation and activation of the apoptosis-associated proteins such as Caspase-3 and PARP-1. Moreover, we investigated the cellular apoptosis pathway involved in the apoptosis process in HepG2 cells. We found that proteins involved in mitochondrion (cleaved-Caspase-9, Apaf-1, HtrA2/Omi, Bax, and Mitochondrial Bax) and endocytoplasmic reticulum (XBP-1s, GRP78, cleaved-Caspase-7 and cleaved-Caspase-12) apoptotic pathways were up-regulated when cells were treated by JA. In addition, a morphological change in the mitochondrion was detected. Furthermore, we found that JA could inhibit DNA synthesis and induce G2/M cell cycle arrest. The expression of G2-to-M transition related proteins, such as CyclinB1 and phosphorylated-CDK1, were reduced. In contrast, the G2-to-M inhibitor p21 was increased in JA-treated cells. Overall, our results suggest that JA can induce mitochondrion- and endocytoplasmic reticulum-mediated apoptosis, and G2/M phase arrest in HepG2 cells, making it a promising therapeutic agent against hepatoma.

  19. Oscillating carbon nanotori along carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Hilder, Tamsyn A.; Hill, James M.

    2007-03-01

    The discovery of carbon nanostructures, such as nanotubes and C60 fullerenes, has given rise to a number of potential nanoscale devices. One such device is the gigahertz oscillator, comprising an inner shell sliding inside an outer shell of a multiwalled carbon nanotube, and which, at least theoretically, generates oscillatory frequencies in the gigahertz range. Following the concept of these gigahertz oscillators and the recent discovery of “fullerene crop circles,” here we propose the notion of a nanotorus-nanotube oscillator comprising a carbon nanotorus which is sucked by the van der Waals force onto the carbon nanotube, and subsequently oscillates along the nanotube axis due to the equal and opposite pulselike forces acting at either end of the nanotube. Assuming a continuum approach, where the interatomic interactions are replaced by uniform atomic surface densities, and assuming that the geometry of the nanotube and nanotorus is such that the nanotorus always remains symmetrically situated around the nanotube, we present the basic mechanics of such a system, including the determination of the suction and acceptance energies, and the frequency of the resulting oscillatory motion. In contrast to the previously studied gigahertz nanoscale oscillators, here the oscillatory frequencies are shown to be in the megahertz range. Our study, although purely theoretical must necessarily precede any experimental implementation of such oscillatory systems.

  20. 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

  1. 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.

  2. Sidération myocardique au cours d'une intoxication au monoxyde de carbone (CO) chez une femme enceinte

    PubMed Central

    Coulibaly, Mahamadoun; Berdai, Mohamed Adnane; Labib, Smael; Harandou, Mustapha

    2015-01-01

    L'intoxication au monoxyde de carbone (CO) est la première cause de décès par intoxication en France. La littérature est ancienne et peu connue. Les signes les plus fréquents de l'intoxication sont la triade: Céphalées; asthénie, faiblesse musculaire surtout des membres inférieurs. Ses conséquences sont potentiellement graves pour le fœtus quand elle survient chez la femme enceinte, il est particulièrement exposé au risque d'hypoxie en raison de la forte affinité de son hémoglobine pour le CO qui traverse aisément le placenta. Les événements cardiovasculaires ne sont pas rares et peuvent être responsable d'une morbi-mortalité assez importante qui peuvent être d'apparition rapide ou secondaire mais régressent habituellement en quelques jours. Des SCA peuvent survenir lors d'une une intoxication au CO avec à l'extrême infarctus myocardique avec surélévation du segment ST. Il paraît légitime de proposer pour toutes les patientes: l’éloignement maternel de la source de CO; l'oxygénothérapie à 100% au masque facial par les services de secours et pendant le transfert; le traitement par oxygénothérapie hyperbare pour toutes les femmes enceintes, le plus rapidement possible et quelque soit l’âge gestationnel. PMID:26405502

  3. Seed germination ecology of feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes].

    PubMed

    Chauhan, Bhagirath S

    2013-01-01

    Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha(-1) was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies.

  4. Seed Germination Ecology of Feather Lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes

    PubMed Central

    Chauhan, Bhagirath S.

    2013-01-01

    Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha-1 was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies. PMID:24255700

  5. Changes in ABA, IAA and JA levels during calyx, fruit and leaves development in cape gooseberry plants (Physalis peruviana L.).

    PubMed

    Álvarez-Flórez, F; López-Cristoffanini, C; Jáuregui, O; Melgarejo, L M; López-Carbonell, M

    2017-06-01

    Changes in abscisic acid (ABA), indole-3-acetic acid (IAA) and jasmonic acid (JA) content in developing calyx, fruits and leaves of Physalis peruviana L. plants were analysed. Plant hormones have been widely studied for their roles in the regulation of various aspects related to plant development and, in particular, into their action during development and ripening of fleshly fruits. The obtained evidences suggest that the functions of these hormones are no restricted to a particular development stage, and more than one hormone is involved in controlling various aspects of plant development. Our results will contribute to understand the role of these hormones during growth and development of calyx, fruits and leaves in cape gooseberry plants. This work offers a good, quickly and efficiently protocol to extract and quantify simultaneously ABA, IAA and JA in different tissues of cape gooseberry plants. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  6. 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

  7. 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.

  8. Novel carbon adsorbents

    NASA Astrophysics Data System (ADS)

    Ghosal, Ranjan

    This work presents a method for altering the surface chemistry of carbon adsorbents based on the reaction of carbon with diazonium salts ("diazotization"). The technique allows the chemical attachment of a variety of species to the carbon surface, in concentrations on the order of 3 mumol/msp2 of available surface area. Specific functional groups can be affixed to the carbon surface by reacting it with the appropriate substituted diazonium salt. The BET surface area of a non-porous carbon black was unchanged after treatment with diazonium salts. However, adsorption of COsb2 at 273 K and 8 Torr increased by as much as 800% over the base material, when polar groups were bonded to the carbon surface by diazotization. Higher levels of treatment resulted in increased COsb2 adsorption. For the same concentration of surface species, surface species of greater polarity resulted in higher COsb2 adsorption. Isosteric heat of adsorption curves for COsb2 (284 K) were obtained on diazotized carbons. The initial heat of adsorption was a function of the type of surface group, and for a particular surface group, was invariant with level of treatment. Surface species of higher polarity increased, and non-polar surface species lowered, the initial heat of adsorption of COsb2. Gas chromatographic (GC) experiments were carried out on columns of untreated and diazotized carbon. Adsorbate retention times on untreated carbon black were independent of adsorbate polarity and proportional to the molecular weight of the adsorbate. However, on a diazotized carbon black with polar surface groups, the retention times of polar adsorbates increased by an order of magnitude in some cases. The same diazotized carbon successfully separated a mixture of butanol isomers based on their polarity. A semi-empirical multi-site adsorption model was used to describe COsb2 adsorption on diazotized carbons. The model successfully accounted for surface heterogeneity and the presence of different types of sites

  9. 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.

  10. 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

  11. Improving carbon fixation pathways

    SciTech Connect

    Ducat, DC; Silver, PA

    2012-08-01

    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 novel pathways and organisms can be utilized to fix atmospheric carbon dioxide into useful materials.

  12. Careers Other Than Academia EPA/AAAS Graduate Fellowship Expo

    EPA Science Inventory

    NCER invited Emilie to speak to the EPA STAR graduate fellows about her transition from graduate school into a postdoctoral position with the EPA. Discussion of what led Emilie to seek a position with the EPA, how she conducted her job search, and what qualities she thinks gradu...

  13. Mapping ExpoCast onto ToxCast

    EPA Science Inventory

    The National Exposure Research Laboratory (NERL) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA mission to protect human health and the environment. HEASD research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EP...

  14. Careers Other Than Academia EPA/AAAS Graduate Fellowship Expo

    EPA Science Inventory

    NCER invited Emilie to speak to the EPA STAR graduate fellows about her transition from graduate school into a postdoctoral position with the EPA. Discussion of what led Emilie to seek a position with the EPA, how she conducted her job search, and what qualities she thinks gradu...

  15. 2011 Joint Service Power Expo. Volume 2. Video Files

    DTIC Science & Technology

    2011-05-05

    Untitled Document 2011power.html[3/22/2016 1:21:48 PM] Files are in Adobe, AVCHD Video (.m2ts), .avi format, MPEG-4 Movie (. mp4 ), and Windows Media...of Sales and Marketing, WindTamer Corporation and Mr. Adeeb Saba WindTamer MPEG-4 Movie (. mp4 ) SESSION 16 On-Board Vehicle Power (OBVP) 1

  16. Online World Conference and Expo: A Zillion Things at Once.

    ERIC Educational Resources Information Center

    Chuck, Lysbeth B.

    1997-01-01

    Presents the keynote speakers of the Online World 1997 conference, as well as HotBot and other search engines, the CyberClinic tracks (Practical Searching, Resource Management, Trends and Technology, Corporate Electronic Publishing, Content Reviews, and Roundtable Discussions), Web-based communities, and an exhibited database of over 12,000…

  17. 2007 Joint Service Power Expo Volume 3 Wednesday videos

    DTIC Science & Technology

    2007-04-26

    navy.mil Session 7 - Chair: Mike Bissonnette mbissonnette@mkisystems.com 8:00 a.m. - 9:30 a.m. Ultralast Chinese Li/ FeS2 Cells - David Hale Associates...Observations, LtCol K. Jansen Battlefield Power for the Warfighter: Lessons for the Development Community, Dr. Ken Zemach, Ph. D., Lion Cells , Inc. OIF...Manuals and Milspecs, Ms Susan Waggoner Solar Power Adapters and Deployable and Renewable Alternative Energy Module, Major David Morris Tactical Power

  18. ACTE Convention and Career-Tech Expo: Racing toward Charlotte

    ERIC Educational Resources Information Center

    Tech Directions, 2008

    2008-01-01

    This article reports on Association for Career and Technical Education's (ACTE's) annual convention to be held this year in Charlotte, North Carolina, from December 4-6. To provide the greatest benefits to attending educators, ACTE will again partner with several other associations at this year's convention. ACTE has lined up three speakers for…

  19. Mapping ExpoCast onto ToxCast

    EPA Science Inventory

    The National Exposure Research Laboratory (NERL) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA mission to protect human health and the environment. HEASD research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EP...

  20. ACTE Convention and Career-Tech Expo: Racing toward Charlotte

    ERIC Educational Resources Information Center

    Tech Directions, 2008

    2008-01-01

    This article reports on Association for Career and Technical Education's (ACTE's) annual convention to be held this year in Charlotte, North Carolina, from December 4-6. To provide the greatest benefits to attending educators, ACTE will again partner with several other associations at this year's convention. ACTE has lined up three speakers for…

  1. 2008 U.S. Coast Guard Innovation Expo

    DTIC Science & Technology

    2008-11-20

    implement “the full ” standard?) (E.g., How do you “synchronize” rollout of standards versions?) (E.g., Will I need to carry another radio to talk to a...people, all platforms, all systems, and all missions always supported. Public Release Authorized Value of DCMS DCMS will enable …  … Full life...tons full load 1,780 tons full load Aviation N/A Flight deck with hangar; HH- 60J or MH-65C helicopter Armament Mk38 25mm machine gun, 2x12.7mm MG

  2. ExpoCast: Exposure Science for Prioritization and Toxicity Testing

    EPA Science Inventory

    The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCastTM. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict potential toxicity and prioritize l...

  3. ExpoCast: Exposure Science for Prioritization and Toxicity Testing

    EPA Science Inventory

    The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCastTM. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict potential toxicity and prioritize l...

  4. Online World Conference and Expo: A Zillion Things at Once.

    ERIC Educational Resources Information Center

    Chuck, Lysbeth B.

    1997-01-01

    Presents the keynote speakers of the Online World 1997 conference, as well as HotBot and other search engines, the CyberClinic tracks (Practical Searching, Resource Management, Trends and Technology, Corporate Electronic Publishing, Content Reviews, and Roundtable Discussions), Web-based communities, and an exhibited database of over 12,000…

  5. Human Skeletal Material from 23JA277 Blue Springs Lake Project, Jackson County, Missouri

    DTIC Science & Technology

    1988-01-01

    Todd 1920; McKern and Stewart 1957) in that the surface of the entire demi-face is flat and granulated in appearance, the ventral rampart is complete...carbonized organic matter, some of which retain a wood-like structure. Dark mottles and the stain coating the bones effervesces with a three percent hydrogen

  6. 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

  7. Elevated CO2 Reduces the Resistance and Tolerance of Tomato Plants to Helicoverpa armigera by Suppressing the JA Signaling Pathway

    PubMed Central

    Ren, Qin; Zhu-Salzman, Keyan; Kang, Le; Wang, Chenzhu; Li, Chuanyou; Ge, Feng

    2012-01-01

    Both resistance and tolerance, which are two strategies that plants use to limit biotic stress, are affected by the abiotic environment including atmospheric CO2 levels. We tested the hypothesis that elevated CO2 would reduce resistance (i.e., the ability to prevent damage) but enhance tolerance (i.e., the ability to regrow and compensate for damage after the damage has occurred) of tomato plants to the cotton bollworm, Helicoverpa armigera. The results showed that elevated CO2 reduced resistance by decreasing the jasmonic acid (JA) level and activities of lipoxygenase, proteinase inhibitors, and polyphenol oxidase in wild-type (WT) plants infested with H. armigera. Consequently, the activities of total protease, trypsin-like enzymes, and weak and active alkaline trypsin-like enzymes increased in the midgut of H. armigera when fed on WT plants grown under elevated CO2. Unexpectedly, the tolerance of the WT to H. armigera (in terms of photosynthetic rate, activity of sucrose phosphate synthases, flower number, and plant biomass and height) was also reduced by elevated CO2. Under ambient CO2, the expression of resistance and tolerance to H. armigera was much greater in wild type than in spr2 (a JA-deficient genotype) plants, but elevated CO2 reduced these differences of the resistance and tolerance between WT and spr2 plants. The results suggest that the JA signaling pathway contributes to both plant resistance and tolerance to herbivorous insects and that by suppressing the JA signaling pathway, elevated CO2 will simultaneously reduce the resistance and tolerance of tomato plants. PMID:22829948

  8. SA-inducible Arabidopsis glutaredoxin interacts with TGA factors and suppresses JA-responsive PDF1.2 transcription.

    PubMed

    Ndamukong, Ivan; Abdallat, Ayed Al; Thurow, Corinna; Fode, Benjamin; Zander, Mark; Weigel, Ralf; Gatz, Christiane

    2007-04-01

    Salicylic acid (SA) is a plant signaling molecule that mediates the induction of defense responses upon attack by a variety of pathogens. Moreover, it antagonizes gene induction by the stress signaling molecule jasmonic acid (JA). Several SA-responsive genes are regulated by basic/leucine zipper-type transcription factors of the TGA family. TGA factors interact with NPR1, a central regulator of many SA-induced defense responses including SA/JA antagonism. In order to identify further regulatory proteins of SA-dependent signaling pathways, a yeast protein interaction screen with tobacco TGA2.2 as bait and an Arabidopsis thaliana cDNA prey library was performed and led to the identification of a member of the glutaredoxin family (GRX480, encoded by At1g28480). Glutaredoxins are candidates for mediating redox regulation of proteins because of their capacity to catalyze disulfide transitions. This agrees with previous findings that the redox state of both TGA1 and NPR1 changes under inducing conditions. Transgenic Arabidopsis plants ectopically expressing GRX480 show near wild-type expression of standard marker genes for SA- and xenobiotic-inducible responses. In contrast, transcription of the JA-dependent defensin gene PDF1.2 was antagonized by transgenic GRX480. This, together with the observation that GRX480 transcription is SA-inducible and requires NPR1, suggests a role of GRX480 in SA/JA cross-talk. Suppression of PDF1.2 by GRX480 depends on the presence of TGA factors, indicating that the GRX480/TGA interaction is effective in planta.

  9. Visualization and Measurement of the Burning Surface of Wire-Embedded Energetic Materials, Part 1: JA2 and Pentolite

    DTIC Science & Technology

    2014-06-01

    figure 4). The apparatus includes a windowed chamber capable of being pressurized up to 10 MPa. It also includes a ballast tank that adds considerably... pressures were acquired, and they can be employed to validate a state-of-the-art CFD model that ARL is developing to accelerate the development of...rates at pressure near 5.18 MPa. ..............................................................12 Figure 11. JA2 burning rates at 6.90 MPa

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Authigenic carbonate and the history of the global carbon cycle.

    PubMed

    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 O(2) 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.

  15. 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).

  16. 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.

  17. Temporal changes in allocation and partitioning of new carbon as (11)C elicited by simulated herbivory suggest that roots shape aboveground responses in Arabidopsis.

    PubMed

    Ferrieri, Abigail P; Agtuca, Beverly; Appel, Heidi M; Ferrieri, Richard A; Schultz, Jack C

    2013-02-01

    Using the short-lived isotope (11)C (t(1/2) = 20.4 min) as (11)CO(2), we captured temporal changes in whole-plant carbon movement and partitioning of recently fixed carbon into primary and secondary metabolites in a time course (2, 6, and 24 h) following simulated herbivory with the well-known defense elicitor methyl jasmonate (MeJA) to young leaves of Arabidopsis (Arabidopsis thaliana). Both (11)CO(2) fixation and (11)C-photosynthate export from the labeled source leaf increased rapidly (2 h) following MeJA treatment relative to controls, with preferential allocation of radiolabeled resources belowground. At the same time, (11)C-photosynthate remaining in the aboveground sink tissues showed preferential allocation to MeJA-treated, young leaves, where it was incorporated into (11)C-cinnamic acid. By 24 h, resource allocation toward roots returned to control levels, while allocation to the young leaves increased. This corresponded to an increase in invertase activity and the accumulation of phenolic compounds, particularly anthocyanins, in young leaves. Induction of phenolics was suppressed in sucrose transporter mutant plants (suc2-1), indicating that this phenomenon may be controlled, in part, by phloem loading at source leaves. However, when plant roots were chilled to 5°C to disrupt carbon flow between above- and belowground tissues, source leaves failed to allocate resources belowground or toward damaged leaves following wounding and MeJA treatment to young leaves, suggesting that roots may play an integral role in controlling how plants respond defensively aboveground.

  18. Carbon Monoxide Poisoning

    MedlinePlus

    ... related Carbon Monoxide Exposures Additional Resources Quick Links Air Pollution & Respiratory Health Air Quality Asthma Mold What's New ... KB] Tiếng Việt [PDF - 89 KB] Quick Links Air Pollution & Respiratory Health Air Quality Asthma Mold What's New ...

  19. 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 ...

  20. Sodium carbonate poisoning

    MedlinePlus

    Sodium carbonate is usually not very toxic. However, if you swallow very large amounts, you may have symptoms. In this rare situation, long-term effects, even death, are possible if you do not receive quick and aggressive treatment.

  1. 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.

  2. [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.

  3. 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.

  4. Carbon partitioning in photosynthesis.

    PubMed

    Melis, Anastasios

    2013-06-01

    The work seeks to raise awareness of a fundamental problem that impacts the renewable generation of fuels and chemicals via (photo)synthetic biology. At issue is regulation of the endogenous cellular carbon partitioning between different biosynthetic pathways, over which the living cell exerts stringent control. The regulation of carbon partitioning in photosynthesis is not understood. In plants, microalgae and cyanobacteria, methods need be devised to alter photosynthetic carbon partitioning between the sugar, terpenoid, and fatty acid biosynthetic pathways, to lower the prevalence of sugar biosynthesis and correspondingly upregulate terpenoid and fatty acid hydrocarbons production in the cell. Insight from unusual but naturally occurring carbon-partitioning processes can help in the design of blueprints for improved photosynthetic fuels and chemicals production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Carbon Monoxide Safety

    MedlinePlus

    ... Media Fire Protection Technology Carbon monoxide safety outreach materials Keep your community informed about the dangers of ... muscular coordination Loss of consciousness Ultimately death Outreach materials from the U.S. Fire Administration Handout: portable generators ...

  6. 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.

  7. 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.

  8. Carbon Dioxide Reduction Systems

    NASA Technical Reports Server (NTRS)

    Burghardt, Stanley I.; Chandler, Horace W.; Taylor, T. I.; Walden, George

    1961-01-01

    The Methoxy system for regenerating oxygen from carbon dioxide was studied. Experiments indicate that the reaction between carbon dioxide and hydrogen can be carried out with ease in an efficient manner and with excellent heat conservation. A small reactor capable of handling the C02 expired by three men has been built and operated. The decomposition of methane by therma1,arc and catalytic processes was studied. Both the arc and catalytic processes gave encouraging results with over 90 percent of the methane being decomposed to carbon and hydrogen in some of the catalytic processes. Control of the carbon deposition in both the catalytic and arc processes is of great importance to prevent catalyst deactivation and short circuiting of electrical equipment. Sensitive analytical techniques have been developed for all of the components present in the reactor effluent streams.

  9. 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.

  10. Carbon Fibers and Composites

    NASA Technical Reports Server (NTRS)

    Pride, R. A.

    1979-01-01

    The basic nature of composite materials is considered. Carbon fiber composites and their area of current and planned application in civil aircraft are discussed, specifically within the framework of the various aspects of risk analysis.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. Soil carbonates and soil water

    USDA-ARS?s Scientific Manuscript database

    The presence of soil carbonates occurring as solidified masses or dispersed particles can alter soil water dynamics from what would be expected based on non-carbonate soil properties. Carbonate minerals in the soil can be derived from high carbonate parent material, additions in the form of carbonat...

  17. Carbon allocation in forest ecosystems

    Treesearch

    Creighton M. Litton; James W. Raich; Michael G. Ryan

    2007-01-01

    Carbon allocation plays a critical role in forest ecosystem carbon cycling. We reviewed existing literature and compiled annual carbon budgets for forest ecosystems to test a series of hypotheses addressing the patterns, plasticity, and limits of three components of allocation: biomass, the amount of material present; flux, the flow of carbon to a component per unit...

  18. 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.

  19. Carbon management and biodiversity.

    PubMed

    Huston, Michael A; Marland, Gregg

    2003-01-01

    International efforts to mitigate human-caused changes in the Earth's climate are considering a system of incentives (debits and credits) that would encourage specific changes in land use that can help to reduce the atmospheric concentration of carbon dioxide. The two primary land-based activities that would help to minimize atmospheric carbon dioxide are carbon storage in the terrestrial biosphere and the efficient substitution of biomass fuels and bio-based products for fossil fuels and energy-intensive products. These two activities have very different land requirements and different implications for the preservation of biodiversity and the maintenance of other ecosystem services. Carbon sequestration in living forests can be pursued on lands with low productivity, i.e. on lands that are least suitable for agriculture or intensive forestry, and are compatible with the preservation of biodiversity over large areas. In contrast, intensive harvest-and-use systems for biomass fuels and products generally need more productive land to be economically viable. Intensive harvest-and-use systems may compete with agriculture or they may shift intensive land uses onto the less productive lands that currently harbor most of the Earth's biodiversity. Win-win solutions for carbon dioxide control and biodiversity are possible, but careful evaluation and planning are needed to avoid practices that reduce biodiversity with little net decrease in atmospheric carbon dioxide. Planning is more complex on a politically subdivided Earth where issues of local interest, national sovereignty, and equity come into play.

  20. 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.

  1. 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.

  2. Functionalized Carbon Nanotubes

    NASA Technical Reports Server (NTRS)

    Lebron, Marisabel; Mintz, Eric; Meador, Michael A.; Hull, David R.; Scheiman, Daniel A.; Willis, Peter; Smalley, Richard E.

    2001-01-01

    Carbon nanotubes have created a great deal of excitement in the Materials Science community because of their outstanding mechanical, electrical, and thermal properties. Use of carbon nanotubes as reinforcements for polymers could lead to a new class of composite materials with properties, durability, and performance far exceeding that of conventional fiber reinforced composites. Organized arrays of carbon nanotubes, e.g., nanotube monolayers, could find applications as thermal management materials, light emitting devices, and sensor arrays. Carbon nanotubes could also be used as templates upon which nanotubes from other materials could be constructed. Successful use of carbon nanotubes in any of these potential applications requires the ability to control the interactions of nanotubes with each other and with other materials, e.g., a polymer matrix. One approach to achieving this control is to attach certain chemical groups to the ends and/or side-walls of the nanotubes. The nature of these chemical groups can be varied to achieve the desired result, such as better adhesion between the nanotubes and a polymer. Under a joint program between NASA Glenn, Clark Atlanta University, and Rice University researchers are working on developing a chemistry "tool-kit" that will enable the functionalization of carbon nanotubes with a variety of chemical groups. Recent results of this effort will be discussed.

  3. 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.

  4. Carbon dioxide poisoning.

    PubMed

    Langford, Nigel J

    2005-01-01

    Carbon dioxide is a physiologically important gas, produced by the body as a result of cellular metabolism. It is widely used in the food industry in the carbonation of beverages, in fire extinguishers as an 'inerting' agent and in the chemical industry. Its main mode of action is as an asphyxiant, although it also exerts toxic effects at cellular level. At low concentrations, gaseous carbon dioxide appears to have little toxicological effect. At higher concentrations it leads to an increased respiratory rate, tachycardia, cardiac arrhythmias and impaired consciousness. Concentrations >10% may cause convulsions, coma and death. Solid carbon dioxide may cause burns following direct contact. If it is warmed rapidly, large amounts of carbon dioxide are generated, which can be dangerous, particularly within confined areas. The management of carbon dioxide poisoning requires the immediate removal of the casualty from the toxic environment, the administration of oxygen and appropriate supportive care. In severe cases, assisted ventilation may be required. Dry ice burns are treated similarly to other cryogenic burns, requiring thawing of the tissue and suitable analgesia. Healing may be delayed and surgical intervention may be required in severe cases.

  5. Diverting the flux of the JA pathway in Nicotiana attenuata compromises the plant's defense metabolism and fitness in nature and glasshouse.

    PubMed

    Stitz, Michael; Baldwin, Ian T; Gaquerel, Emmanuel

    2011-01-01

    A plant's inducible defenses against herbivores as well as certain developmental processes are known to be controlled by the jasmonic acid (JA) pathway. We have previously shown that ectopically expressing Arabidopsis thaliana JA O-methyltransferase in Nicotiana attenuata (35S-jmt) strongly reduces the herbivory-elicited jasmonate bursts by acting as metabolic sink that redirects free JA towards methylation; here we examine the consequences of this metabolic sink on N. attenuata's secondary metabolism and performance in nature. In the glasshouse, 35S-jmt plants produced fewer seed capsules due to shorter floral styles, which could be restored to wild type (WT) levels after hand-pollination, and were more susceptible to Manduca sexta larvae attack. When transplanted into the Great Basin Desert in Utah, 35S-jmt plants grew as well as WT empty vector, but were highly attacked by native herbivores of different feeding guilds: leaf chewers, miners, and single cell feeders. This greater susceptibility was strongly associated with reduced emissions of volatile organic compounds (hexenylesters, monoterpenes and sesquiterpenes) and profound alterations in the production of direct defenses (trypsin proteinase inhibitors [TPI], nicotine, diterpene glycosides [DTGs] and phenylpropanoid-polyamine conjugates) as revealed by a combination of targeted and metabolomics analyses of field collected samples. Complementation experiments with JA-Ile, whose formation is outcompeted in 35S-jmt plants by the methylation reaction, restored the local TPI activation to WT levels and partially complemented nicotine and DTG levels in elicited but not systemic leaves. These findings demonstrate that MeJA, the major JA metabolite in 35S-jmt plants, is not an active signal in defense activation and highlights the value of creating JA sinks to disrupt JA signaling, without interrupting the complete octadecanoid pathway, in order to investigate the regulation of plants' defense metabolism in nature.

  6. Diverting the Flux of the JA Pathway in Nicotiana attenuata Compromises the Plant's Defense Metabolism and Fitness in Nature and Glasshouse

    PubMed Central

    Stitz, Michael; Baldwin, Ian T.; Gaquerel, Emmanuel

    2011-01-01

    A plant's inducible defenses against herbivores as well as certain developmental processes are known to be controlled by the jasmonic acid (JA) pathway. We have previously shown that ectopically expressing Arabidopsis thaliana JA O-methyltransferase in Nicotiana attenuata (35S-jmt) strongly reduces the herbivory-elicited jasmonate bursts by acting as metabolic sink that redirects free JA towards methylation; here we examine the consequences of this metabolic sink on N. attenuata's secondary metabolism and performance in nature. In the glasshouse, 35S-jmt plants produced fewer seed capsules due to shorter floral styles, which could be restored to wild type (WT) levels after hand-pollination, and were more susceptible to Manduca sexta larvae attack. When transplanted into the Great Basin Desert in Utah, 35S-jmt plants grew as well as WT empty vector, but were highly attacked by native herbivores of different feeding guilds: leaf chewers, miners, and single cell feeders. This greater susceptibility was strongly associated with reduced emissions of volatile organic compounds (hexenylesters, monoterpenes and sesquiterpenes) and profound alterations in the production of direct defenses (trypsin proteinase inhibitors [TPI], nicotine, diterpene glycosides [DTGs] and phenylpropanoid-polyamine conjugates) as revealed by a combination of targeted and metabolomics analyses of field collected samples. Complementation experiments with JA-Ile, whose formation is outcompeted in 35S-jmt plants by the methylation reaction, restored the local TPI activation to WT levels and partially complemented nicotine and DTG levels in elicited but not systemic leaves. These findings demonstrate that MeJA, the major JA metabolite in 35S-jmt plants, is not an active signal in defense activation and highlights the value of creating JA sinks to disrupt JA signaling, without interrupting the complete octadecanoid pathway, in order to investigate the regulation of plants' defense metabolism in nature

  7. 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.

  8. Programmable high crystallinity carbon patterns

    NASA Astrophysics Data System (ADS)

    Wang, Xuewen; Wang, Hong; Gu, Yang; Fu, Wei; Zheng, Lu; Liu, Guowei; He, Yongmin; Long, Yi; Zhao, Wu; Zhang, Jie; Zhang, Ting; Liu, Zheng

    2017-06-01

    Carbon nanomaterials such as carbon nanotube and graphene are promising candidates for next-generation flexible electronics. However, the practical application of carbon electronics requires controlled fabrication of those materials with micro-patterned structures on flexible substrate at wafer-scale and low cost. Inspiring from the conventional photolithography process and pyrolysis of photoresist, herein, we demonstrate the synthesis of high-quality micro-patterned high crystallinity carbon. The method employed pre-patterned pyrolyzed photoresist as carbon precursors, in order to minimize the mobility of carbon during the high temperature growth, which results into high quality carbon patterns with a lateral resolution up to ~2 µm. The flexible carbon electronics are demonstrated by transferring the as-patterned high crystallinity carbon patterns to the flexible substrate, and showing asymmetric tensile-compressive response with high output resolution. These results will pave the way to the next-generation carbon-based flexible electronics and mechanical sensors.

  9. Carbon isotope effects in carbonate systems

    NASA Astrophysics Data System (ADS)

    Deines, Peter

    2004-06-01

    Global carbon cycle models require a complete understanding of the δ 13C variability of the Earth's C reservoirs as well as the C isotope effects in the transfer of the element among them. An assessment of δ 13C changes during CO 2 loss from degassing magmas requires knowledge of the melt-CO 2 carbon isotope fractionation. In order to examine the potential size of this effect for silicate melts of varying composition, 13C reduced partition functions were computed in the temperature range 275 to 4000 K for carbonates of varying bond strengths (Mg, Fe, Mn, Sr, Ba, Pb, Zn, Cd, Li, and Na) and the polymorphs of calcite. For a given cation and a given pressure the 13C content increases with the density of the carbonate structure. For a given structure the tendency to concentrate 13C increases with pressure. The effect of pressure (‰/10 kbar) on the size of the reduced partition function of aragonite varies with temperature; in the pressure range 1 to 10 5 bars the change is given by: Δ 13C p average=-0.01796+0.06635∗ 10 3/T+0.006875∗ 10 6/T2 For calcite III the pressure effect is on average 1.4× larger than that for aragonite at all temperatures. The nature of the cation in a given structure type has a significant effect on the carbon isotope fractionation properties. The tendency to concentrate 13C declines in the series magnesite, aragonite, dolomite, strontianite, siderite, calcite, smithonite, witherite, rhodochrosite, otavite, cerrusite. For divalent cations a general expression for an estimation of the reduced partition function (β) from the reduced mass (μ = [M Cation × M Carbonate]/[M Cation + M Carbonate]) is: 1000 lnβ=(0.032367-0.072563∗ 10 3/T-0.01073∗ 10 6/T2)∗μ-14.003+29.953∗ 10 3/T+9.4610∗ 10 6/T2 For Mg-calcite the 13C content varies with the Mg concentration. The fractionation between Mg-calcite (X = mole fraction of MgCO 3) and calcite is given by: 1000 ln(α MgCalite- Calcite)=[0.013702-0.10957× 10 3/T+1.35940× 10 6/T2

  10. Implications of carbon dust emission for terrestrail carbon cycling and carbon accounting

    USDA-ARS?s Scientific Manuscript database

    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,...

  11. Measurement of carbon capture efficiency and stored carbon leakage

    SciTech Connect

    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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. Carbon fuel particles used in direct carbon conversion fuel cells

    DOEpatents

    Cooper, John F [Oakland, CA; Cherepy, Nerine [Oakland, CA

    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.

  2. 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.

  3. 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.

  4. Single-wall-carbon-nanotube/single-carbon-chain molecular junctions

    NASA Astrophysics Data System (ADS)

    Börrnert, Felix; Börrnert, Carina; Gorantla, Sandeep; Liu, Xianjie; Bachmatiuk, Alicja; Joswig, Jan-Ole; Wagner, Frank R.; Schäffel, Franziska; Warner, Jamie H.; Schönfelder, Ronny; Rellinghaus, Bernd; Gemming, Thomas; Thomas, Jürgen; Knupfer, Martin; Büchner, Bernd; Rümmeli, Mark H.

    2010-02-01

    Stable junctions between a single carbon chain and two single-wall carbon nanotubes were produced via coalescence of functionalized fullerenes filled into a single-wall carbon nanotube and directly imaged by in situ transmission electron microscopy. First principles quantum chemical calculations support the observed stability of such molecular junctions. They also show that short carbon chains bound to other carbon structures are cumulenes and stable semiconductors due to Peierls-like distortion. Junctions like this can be regarded as archetypical building blocks for all-carbon molecular electronics.

  5. 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.

  6. 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.

  7. A bHLH-Type Transcription Factor, ABA-INDUCIBLE BHLH-TYPE TRANSCRIPTION FACTOR/JA-ASSOCIATED MYC2-LIKE1, Acts as a Repressor to Negatively Regulate Jasmonate Signaling in Arabidopsis[C][W

    PubMed Central

    Nakata, Masaru; Mitsuda, Nobutaka; Herde, Marco; Koo, Abraham J.K.; Moreno, Javier E.; Suzuki, Kaoru; Howe, Gregg A.; Ohme-Takagi, Masaru

    2013-01-01

    Jasmonates (JAs) are plant hormones that regulate the balance between plant growth and responses to biotic and abiotic stresses. Although recent studies have uncovered the mechanisms for JA-induced responses in Arabidopsis thaliana, the mechanisms by which plants attenuate the JA-induced responses remain elusive. Here, we report that a basic helix-loop-helix–type transcription factor, ABA-INDUCIBLE BHLH-TYPE TRANSCRIPTION FACTOR/JA-ASSOCIATED MYC2-LIKE1 (JAM1), acts as a transcriptional repressor and negatively regulates JA signaling. Gain-of-function transgenic plants expressing the chimeric repressor for JAM1 exhibited substantial reduction of JA responses, including JA-induced inhibition of root growth, accumulation of anthocyanin, and male fertility. These plants were also compromised in resistance to attack by the insect herbivore Spodoptera exigua. Conversely, jam1 loss-of-function mutants showed enhanced JA responsiveness, including increased resistance to insect attack. JAM1 and MYC2 competitively bind to the target sequence of MYC2, which likely provides the mechanism for negative regulation of JA signaling and suppression of MYC2 functions by JAM1. These results indicate that JAM1 negatively regulates JA signaling, thereby playing a pivotal role in fine-tuning of JA-mediated stress responses and plant growth. PMID:23673982

  8. 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/)

  9. 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.

  10. 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.

  11. 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.

  12. Carbon Fibers Conductivity Studies

    NASA Technical Reports Server (NTRS)

    Yang, C. Y.; Butkus, A. M.

    1980-01-01

    In an attempt to understand the process of electrical conduction in polyacrylonitrile (PAN)-based carbon fibers, calculations were carried out on cluster models of the fiber consisting of carbon, nitrogen, and hydrogen atoms using the modified intermediate neglect of differential overlap (MINDO) molecular orbital (MO) method. The models were developed based on the assumption that PAN carbon fibers obtained with heat treatment temperatures (HTT) below 1000 C retain nitrogen in a graphite-like lattice. For clusters modeling an edge nitrogen site, analysis of the occupied MO's indicated an electron distribution similar to that of graphite. A similar analysis for the somewhat less stable interior nitrogen site revealed a partially localized II electron distribution around the nitrogen atom. The differences in bonding trends and structural stability between edge and interior nitrogen clusters led to a two-step process proposed for nitrogen evolution with increasing HTT.

  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. 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.

  15. Carbon in Orion

    NASA Astrophysics Data System (ADS)

    Walter, D. K.

    1991-08-01

    The carbon abundance in the Orion nebula is redetermined from a detailed study of UV spectra in the IUE archives. Temperature and electron density gradients were derived for the inner 5 arcmin of the nebula using new and existing observational data. These temperatures and densities were used to calculate the carbon abundance for 19 positions largely north or west of the Trapezium. The new carbon abundance is found to be log(C/H) + 12 = 7.83 (+0.13, -0.20). This is 0.5-0.7 dex lower than previous studies found. New atomic parameters, a newer UV-extinction curve, and higher temperatures account for these differences from previous studies. C/H and C/O are found to be constant across the face of the nebula. The influence of temperature fluctuations on abundances was investigated.

  16. The Pyrogenic Carbon Cycle

    NASA Astrophysics Data System (ADS)

    Bird, Michael I.; Wynn, Jonathan G.; Saiz, Gustavo; Wurster, Christopher M.; McBeath, Anna

    2015-05-01

    Pyrogenic carbon (PyC; includes soot, char, black carbon, and biochar) is produced by the incomplete combustion of organic matter accompanying biomass burning and fossil fuel consumption. PyC is pervasive in the environment, distributed throughout the atmosphere as well as soils, sediments, and water in both the marine and terrestrial environment. The physicochemical characteristics of PyC are complex and highly variable, dependent on the organic precursor and the conditions of formation. A component of PyC is highly recalcitrant and persists in the environment for millennia. However, it is now clear that a significant proportion of PyC undergoes transformation, translocation, and remineralization by a range of biotic and abiotic processes on comparatively short timescales. Here we synthesize current knowledge of the production, stocks, and fluxes of PyC as well as the physical and chemical processes through which it interacts as a dynamic component of the global carbon cycle.

  17. 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.

  18. Monoalkyl carbonates in carbonated alcoholic beverages.

    PubMed

    Rossi, Marcelo Rabello; Vidal, Denis Tadeu Rajh; do Lago, Claudimir Lucio

    2012-07-15

    The presence of monoethyl carbonate (MEC) in beer and sparkling wine is demonstrated for the first time, as well as the formation of this species in drinks prepared with a distilled beverage and a carbonated soft drink. A capillary electrophoresis (CE) equipment with two capacitively coupled contactless conductivity detector (C(4)D) was used to identify and quantify this species. The concentrations of MEC in samples of lager beer and rum and cola drink were, respectively, 1.2 and 4.1 mmol/l, which agree with the levels of ethanol and CO2 available in these products. Previous results about the kinetics of the reaction suggest that only a small amount of MEC should be formed after the ingredients of a drink are mixed. However, in all three cases (whisky and club soda; rum with cola; gin and tonic water), MEC was quickly formed, which was attributed to the low pH of the drinks. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. 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.

  20. 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.

  1. 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.

  2. Carbon microstructures for electrochemical studies

    SciTech Connect

    Kostecki, Robert; Song, Xiang Yun; Kinoshita, Kim

    2001-06-22

    Thin layers of photoresist were spin coated onto silicon wafers, and then carbonized to form smooth carbon films by heating in nitrogen for 1 hour at temperatures between 600 to 1100 C. Well-defined carbon microstructures on Si wafers that are being considered for electrodes in a microbattery concept were obtained by additional processing steps involving patterning and lithography of the photoresist prior to carbonization. The status of the fabrication of carbon microelectrodes obtained by pyrolysis of photoresist, characterization of the carbons by surface-sensitive techniques and electrochemical analysis by cyclic voltammetry of the I{sup -}/I{sub 3}{sup -} redox reaction is described.

  3. Inkjet Printing of Carbon Nanotubes.

    PubMed

    Tortorich, Ryan P; Choi, Jin-Woo

    2013-07-29

    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.

  4. Global Carbon Budget 2016

    SciTech Connect

    Le Quéré, C.; Andrew, R. M.; Canadell, Josep G.; Sitch, Stephen; Boden, T. A.; al., et

    2016-01-01

    The use of data is conditional on citing the original data sources. Full details on how to cite the data are given at the top of each page. For research projects, if the data are essential to the work, or if an important result or conclusion depends on the data, co-authorship may need to be considered. The Global Carbon Project facilitates access to data to encourage its use and promote a good understanding of the carbon cycle. Respecting original data sources is key to help secure the support of data providers to enhance, maintain and update valuable data.

  5. Global Carbon Budget 2015

    SciTech Connect

    Le Quere, C.; Moriarty, R.; Andrew, R. M.; Canadell, J. G.; Sitch, S.; Boden, T. A.; al., et

    2015-01-01

    The use of data is conditional on citing the original data sources. Full details on how to cite the data are given at the top of each page. For research projects, if the data are essential to the work, or if an important result or conclusion depends on the data, co-authorship may need to be considered. The Global Carbon Project facilitates access to data to encourage its use and promote a good understanding of the carbon cycle. Respecting original data sources is key to help secure the support of data providers to enhance, maintain and update valuable data.

  6. 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.

  7. 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

  8. 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.

  9. Photoconductivity in Carbon Fibers.

    DTIC Science & Technology

    1987-10-30

    4191 728 PHOTOCONDUCTIVITY IN CARBON FJ9KRS(U) INARS S INST OF TECH CANMRIDGE J STEINBECK ET RL 39 OCT 87 RFOSR-TR-88-6228 F49929-85-C-8i47...r ’ r y ... : SS f3l~f lJ Photoconductivity - in Graohite Fibers J. Steinbeck , F.Yu, G.Braunstein, G.Dresselhaus, M.S.Dresselhaus and T.VenkaLesan...8217I iFOSR’ 88 - 0228 Photoconductivity in Carbon Fibers J. Steinbeck , F. Yu, G. Braunstein, G. Dresselhaus, M.S. Dresselhaus, Massachusetts Institute

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Electron Beam Exposure of Thermal Control Paints on Carbon-Carbon and Carbon-Polyimide Composites

    NASA Astrophysics Data System (ADS)

    Jaworske, Donald A.

    2006-01-01

    Carbon-carbon and carbon-polyimide composites are being considered for use as radiator face sheets or fins for space radiator applications. Several traditional white thermal control paints are being considered for the surface of the composite face sheets or fins. One threat to radiator performance is high energy electrons. The durability of the thermal control paints applied to the carbon-carbon and carbon-polyimide composites was evaluated after extended exposure to 4.5 MeV electrons. Electron exposure was conducted under argon utilizing a Mylar™ bag enclosure. Solar absorptance and infrared emittance was evaluated before and after exposure to identify optical properties degradation. Adhesion of the paints to the carbon-carbon and carbon-polyimide composite substrates was also of interest. Adhesion was evaluated on pristine and electron beam exposed coupons using a variation of the ASTM D-3359 tape test. Results of the optical properties evaluation and the adhesion tape tests are summarized.

  17. CarbonSat Constellation

    NASA Astrophysics Data System (ADS)

    Sun, Wei; Tobehn, Carsten; Ernst, Robert; Bovensmann, Heinrich; Buchwitz, Michael; Burrows, John P.; Notholt, John

    1 Carbon dioxide (CO2) and methane (CH4) are the most important manmade greenhouse gases (GHGs) which are driving global climate change. Currently, the CO2 measurements from the ground observing network are still the main sources of information but due to the limited number of measurement stations the coverage is limited. In addition, CO2 monitoring and trading is often based mainly on bottom-up calculations and an independent top down verification is limited due to the lack of global measurement data with local resolution. The first CO2 and CH4 mapping from SCIAMACHY on ENVISAT shows that satellites add important missing global information. Current GHG measurement satellites (GOSAT)are limited either in spatial or temporal resolution and coverage. These systems have to collect data over a year or even longer to produce global regional fluxes products. Conse-quently global, timely, higher spatial resolution and high accuracy measurement are required for: 1. A good understanding of the CO2 and CH4 sources and sinks for reliable climate predic-tion; and 2. Independent and transparent verification of accountable sources and sinks in supporting Kyoto and upcoming protocols The CarbonSat constellation idea comes out the trade off of resolution and swath width during CarbonSat mission definition studies. In response to the urgent need to support the Kyoto and upcoming protocols, a feasibility study has been carried out. The proposed solution is a constellation of five CarbonSat satellites in 614km LTAN 13:00, which is able to provide global, daily CO2 and CH4 measurement everywhere on the Earth with high spatial resolution 2 × 2 km and low uncertainty lt;2ppm (CO2) and lt;8ppb (CH4). The unique global daily measurement capability significantly increases the number of cloud free measurements, which enables more reliable services associated with reduced uncertainty, e.g. to 0.15ppm (CO2) per month in 10km and even more timely products. The CarbonSat Constellation in

  18. 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.

  19. 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.

  20. Fixation of carbon dioxide into dimethyl carbonate over ...

    EPA Pesticide Factsheets

    A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydrating agent or requirement for azeotropic distillation. Prepared for submission to Nature Scientific reports.

  1. 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.

  2. 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

  3. Adaptive Carbon Allocation by Plants Enhances the Terrestrial Carbon Sink.

    PubMed

    Xia, Jiangzhou; Yuan, Wenping; Wang, Ying-Ping; Zhang, Quanguo

    2017-06-13

    Carbon allocation is one of the most important physiological processes to optimize the plant growth, which exerts a strong influence on ecosystem structure and function, with potentially large implications for the global carbon budget. However, it remains unclear how the carbon allocation pattern has changed at global scale and impacted terrestrial carbon uptake. Based on the Community Atmosphere Biosphere Land Exchange (CABLE) model, this study shows the increasing partitioning ratios to leaf and wood and reducing ratio to root globally from 1979 to 2014. The results imply the plant optimizes carbon allocation and reaches its maximum growth by allocating more newly acquired photosynthate to leaves and wood tissues. Thus, terrestrial vegetation has absorbed 16% more carbon averagely between 1979 and 2014 through adjusting their carbon allocation process. Compared with the fixed carbon allocation simulation, the trend of terrestrial carbon sink from 1979 to 2014 increased by 34% in the adaptive carbon allocation simulation. Our study highlights carbon allocation, associated with climate change, needs to be mapped and incorporated into terrestrial carbon cycle estimates.

  4. Australian carbon dust emission: a carbon accounting omission?

    USDA-ARS?s Scientific Manuscript database

    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...

  5. The Kane Experimental Forest carbon inventory: Carbon reporting with FVS

    Treesearch

    Coeli Hoover; Stephanie Rebain

    2008-01-01

    As the number of state and regional climate change agreements grows, so does the need to assess the carbon implications of planned forest management actions. At the operational level, producing detailed stock estimates for the primary carbon pools becomes time-consuming and cumbersome. Carbon reporting functionality has been fully integrated within the Forest...

  6. Microbial carbon cycling in Lost City hydrothermal chimneys and other serpentinite-hosted ecosystems (Invited)

    NASA Astrophysics Data System (ADS)

    Brazelton, W. J.; Lang, S. Q.; Morrill, P. L.; Twing, K. I.; Crespo-Medina, M.; Morgan-Smith, D.; Früh-Green, G. L.; Schrenk, M. O.

    2013-12-01

    contrast to the dense populations of methanogen-like archaea in Lost City chimneys. Clearly, the role of methanogens must be constrained in order to gain a firm understanding of the carbon flux from serpentinite ecosystems, and future potential investigations of these systems will be discussed. References 1. Schrenk MO, Brazelton WJ, Lang SQ. 2013. Rev. Mineral. Geochem. 75:575-606. 2. Schrenk MO, Kelley DS, Bolton SA, Baross JA. 2004. Environ. Microbiol. 6:1086-1095. 3. Brazelton WJ, Schrenk MO, Kelley DS, Baross JA. 2006. Appl. Environ. Microbiol. 72:6257-6270. 4. Brazelton WJ, Mehta MP, Kelley DS, Baross JA. 2011. mBio2:4. doi:10.1128/mBio.00127-11. 5. Lang SQ, Früh-Green GL, Bernasconi SM, Lilley MD, Proskurowski G, Méhay S, Butterfield D a. 2012. Geochim. Cosmochim. Acta. 92:82-99. 6. Brazelton WJ, Morrill PL, Szponar N, Schrenk MO. 2013. Appl. Environ. Microbiol. 79:3906.

  7. The friction and wear of carbon-carbon composites for aircraft brakes

    NASA Astrophysics Data System (ADS)

    Hutton, Toby

    Many carbon-carbon composite aircraft brakes encounter high wear rates during low energy braking operations. The work presented in this thesis addresses this issue, but it also elucidates the microstructural changes and wear mechanisms that take place in these materials during all braking conditions encountered by aircraft brakes. A variety of investigations were conducted using friction and wear testing, as well as examination of wear surfaces and wear debris using OM, SEM, X-RD, TGA and Density Gradient Separation (DOS). Friction and wear tests were conducted on a PAN fibre/CVI matrix carbon-carbon composite (Dunlop) and a pitch fibre/Resin-CVI matrix carbon-carbon composite (Bendix). Extensive testing was undertaken on the Dunlop composites to asses the effects of composite architecture, fibre orientation and heat treatment temperatures on friction and wear. Other friction and wear tests, conducted on the base Dunlop composite, were used to investigate the relative influences of temperature and sliding speed. It was found that the effect of temperature was dominant over composite architecture, fibre orientation and sliding speed in governing the friction and wear performance of the Dunlop composites. The development of bulk temperatures in excess of 110 C by frictional heating resulted in smooth friction and a low wear rate. Reducing heat treatment temperature also reduced the thermal conductivity producing high interface temperatures, low smooth friction coefficients and low wear rates under low energy braking conditions. However, this was at the expense of high oxidative wear rates under higher energy braking conditions. The Bendix composites had lower thermal conductivities than the fully heat treated Dunlop composite and exhibited similar friction and wear behaviour to Dunlop composites heat treated to lower temperatures. Examination of the wear surfaces using OM and SEM revealed particulate or Type I surface debris on wear surfaces tested under low energy

  8. 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)

  9. 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.

  10. Carbon Nanotube Solar Cells

    PubMed Central

    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. PMID:22655070

  11. 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.

  12. 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)

  13. 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.

  14. 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

  15. 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.

  16. Nanostructured Carbon Coatings

    DTIC Science & Technology

    2000-01-01

    coatings having a low- friction coefficient for a variety of applications, from heavy-load bearings to nanocoatings for MEMS; protective coating for...tribological coatings having a low-friction coefficient for a variety of applications, from heavy- load bearings to nanocoatings for MEMS. Carbon

  17. 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.

  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. Life without Carbon?

    NASA Astrophysics Data System (ADS)

    Cuntz, Manfred; Williams, Peter E.

    2006-05-01

    Carbon is the centerpiece of all life on Earth and one of the most abundant elements in the Solar System and Sun-like stars. Yet alien biochemistries and one's choice of a definition of life offer possibility for other forms of life.

  20. 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.

  1. 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.

  2. Lanthanum carbonate (Shire).

    PubMed

    Locatelli, Francesco; D'Amico, Marco; Pontoriero, Giuseppe

    2003-07-01

    Shire Pharmaceuticals Group plc, under exclusive license from AnorMED Inc (a subsidiary of Johnson Matthey), is developing lanthanum carbonate, a phosphate-binding lanthanum salt, for the potential treatment of hyperphosphatemia in dialysis patients. It is currently in pre-registration in the US, Canada and Western Europe, and earlier stage clinical trials are ongoing in Japan.

  3. Carbon Slurry Secondary Atomization.

    DTIC Science & Technology

    1986-09-01

    ELEMENT NO. NO. N ACCESSION NO. 1 62203F 3048 I 05 I 34 11 TITLE (Include Securty Clasification ) Carbon Slurry Secondary Atomization 12. PERSONAL AUTHOR(S...density, size, and induction time. Any continuing program in this area should attempt to keep these criteria in mind . IV. VOLATILE ADDITIVE STUDIES 1

  4. 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.

  5. Carbon isotope fractionation in wood during carbonization

    NASA Astrophysics Data System (ADS)

    Turney, C. S. M.; Wheeler, D.; Chivas, Allan R.

    2006-02-01

    A significant uncertainty exists as to whether δ 13C values in charcoal meaningfully represent the stable isotopic content of the original material, with studies suggesting variable responses to both natural and laboratory heating. An extensive study was undertaken using fully homogenised samples of wood taken from Eucalyptus spp., Quercus robur and Pinus radiata. The results demonstrate that the duration of heating had no tangible effect on the final composition of the charred material, with the δ 13C and carbon content of wood fixed after 30 min of heating. Furthermore, all three wood types become progressively depleted in 13C with increasing temperature. The results demonstrate that even at temperatures commonly reached in natural fires (<450 °C) isotopic fractionation of up to 1.3‰ can take place indicating that the absolute values obtained from charcoal extracted for paleoenvironmental reconstruction must be interpreted with caution.

  6. 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.

  7. Squeezing the arctic carbon balloon

    Treesearch

    Evan S. Kane

    2012-01-01

    The advancement of trees into Arctic tundra can increase total aboveground carbon storage. A study now shows, however, that greater plant growth also enhances belowground decomposition, resulting in a net loss of carbon from the ecosystem.

  8. 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.

  9. 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.

  10. Carbon Diffusion in Zircon

    NASA Astrophysics Data System (ADS)

    Cherniak, D. J.; Watson, E. B.; Boehnke, P.; Harrison, T. M.

    2016-12-01

    With the recent discovery of potentially biogenic carbon in 4.1 billion-year-old zircon (Bell et al., 2015), it is important to understand diffusion of C in zircon in order to assess the potential of these carbonaceous inclusions to preserve isotopic evidence of Earth's early history. In this study, we have characterized carbon diffusion in natural zircon at 1-atm and under high-pressure conditions in the presence of hydrous species. The 1-atm experiments were conducted by implanting 13C into polished, oriented slabs of zircon, with implanted samples heated in air or under buffered conditions in silica glass ampoules sealed under vacuum. High-pressure experiments (1 GPa) were conducted in a piston-cylinder apparatus, using 13C labeled glycine as the starting source (this breaks down at run conditions). In all cases, 13C distributions in zircon were measured by Nuclear Reaction Analysis (NRA) using the reaction 13C(p,γ)14N. In addition to the NRA measurements, we have also conducted analyses of carbon in zircon by ion microprobe. For diffusion parallel to c we obtain a well-constrained Arrhenius relation over the temperature range 600-1100°C. Diffusion normal to c is similar. Data from the high-pressure experiments and those run under buffered conditions also yield similar diffusivities, suggesting that carbon diffusion is not significantly affected by these parameters over the range of conditions studied. Carbon diffuses more rapidly than most cations in zircon, with the exception of lithium, but several orders of magnitude more slowly than helium. Zircon will therefore be moderately retentive of carbon. For example, diffusion distances on Gyr timescales would be on order of nm at 200°C, μm at 350°C and mm at 650°C, suggesting that carbon isotopic signatures contained within carbonaceous inclusions in zircon may be retained over long timeframes if zircons experience only moderate heating. E.A. Bell, P. Boehnke, T. M. Harrison, W.L. Mao (2015) PNAS 47, 14518-14521

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  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. Boron nitride converted carbon fiber

    SciTech Connect

    Rousseas, Michael; Mickelson, William; Zettl, Alexander K.

    2016-04-05

    This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.

  19. ABA Is an Essential Signal for Plant Resistance to Pathogens Affecting JA Biosynthesis and the Activation of Defenses in Arabidopsis[W

    PubMed Central

    Adie, Bruce A.T.; Pérez-Pérez, Julián; Pérez-Pérez, Manuel M.; Godoy, Marta; Sánchez-Serrano, José-J.; Schmelz, Eric A.; Solano, Roberto

    2007-01-01

    Analyses of Arabidopsis thaliana defense response to the damping-off oomycete pathogen Pythium irregulare show that resistance to P. irregulare requires a multicomponent defense strategy. Penetration represents a first layer, as indicated by the susceptibility of pen2 mutants, followed by recognition, likely mediated by ERECTA receptor-like kinases. Subsequent signaling of inducible defenses is predominantly mediated by jasmonic acid (JA), with insensitive coi1 mutants showing extreme susceptibility. In contrast with the generally accepted roles of ethylene and salicylic acid cooperating with or antagonizing, respectively, JA in the activation of defenses against necrotrophs, both are required to prevent disease progression, although much less so than JA. Meta-analysis of transcriptome profiles confirmed the predominant role of JA in activation of P. irregulare–induced defenses and uncovered abscisic acid (ABA) as an important regulator of defense gene expression. Analysis of cis-regulatory sequences also revealed an unexpected overrepresentation of ABA response elements in promoters of P. irregulare–responsive genes. Subsequent infections of ABA-related and callose-deficient mutants confirmed the importance of ABA in defense, acting partly through an undescribed mechanism. The results support a model for ABA affecting JA biosynthesis in the activation of defenses against this oomycete. PMID:17513501

  20. OsMYC2, an essential factor for JA-inductive sakuranetin production in rice, interacts with MYC2-like proteins that enhance its transactivation ability

    PubMed Central

    Ogawa, Satoshi; Miyamoto, Koji; Nemoto, Keiichirou; Sawasaki, Tatsuya; Yamane, Hisakazu; Nojiri, Hideaki; Okada, Kazunori

    2017-01-01

    Biosynthesis of sakuranetin, a flavonoid anti-fungal phytoalexin that occurs in rice, is highly dependent on jasmonic acid (JA) signalling and induced by a variety of environmental stimuli. We previously identified OsNOMT, which encodes naringenin 7-O-methyltransferase (NOMT); NOMT is a key enzyme for sakuranetin production. Although OsNOMT expression is induced by JA treatment, the regulation mechanism that activates the biosynthetic pathway of sakuranetin has not yet been elucidated. In this study, we show that JA-inducible basic helix-loop-helix transcriptional factor OsMYC2 drastically enhances the activity of the OsNOMT promoter and is essential for JA-inducible sakuranetin production. In addition, we identified 2 collaborators of OsMYC2, OsMYC2-like protein 1 and 2 (OsMYL1 and OsMYL2) that further activated the OsNOMT promoter in synergy with OsMYC2. Physical interaction of OsMYC2 with OsMYL1 and OsMYL2 further supported the idea that these interactions lead to the enhancement of the transactivation activity of OsMYC2. Our results indicate that JA signalling via OsMYC2 is reinforced by OsMYL1 and OsMYL2, resulting in the inductive production of sakuranetin during defence responses in rice. PMID:28067270

  1. Low Carbon Development of Hainan

    NASA Astrophysics Data System (ADS)

    Yi, Feng; Kun, Zhang

    With the construction of Hainan international tourism island rising to a national strategy level, the green growth pattern based on low carbon objectives will become a significant part in the development of Hainan's economy. In this paper, low carbon electric power system and differentiation service will be discussed, and some opinions were brought up to have a good impact on Hainan's low carbon development.

  2. Dispersion toughened silicon carbon ceramics

    DOEpatents

    Wei, G.C.

    1984-01-01

    Fracture resistant silicon carbide ceramics are provided by incorporating therein a particulate dispersoid selected from the group consisting of (a) a mixture of boron, carbon and tungsten, (b) a mixture of boron, carbon and molybdenum, (c) a mixture of boron, carbon and titanium carbide, (d) a mixture of aluminum oxide and zirconium oxide, and (e) boron nitride. 4 figures.

  3. CARBON IN FORESTS: QUALITY MATTERS

    EPA Science Inventory

    The nature of carbon in forests is discussed from the perspective of carbon sequestration and global climate change. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Areas vulnerable to climate change with respect to ca...

  4. Carbon Cloth Supports Catalytic Electrodes

    NASA Technical Reports Server (NTRS)

    Lu, W. T. P.; Ammon, R. L.

    1983-01-01

    Carbon cloth is starting material for promising new catalytic electrodes. Carbon-cloth electrodes are more efficient than sintered-carbon configuration previously used. Are also chemically stable and require less catalyst--an important economic advantage when catalyst is metal such as platinum.

  5. CARBON IN FORESTS: QUALITY MATTERS

    EPA Science Inventory

    The nature of carbon in forests is discussed from the perspective of carbon sequestration and global climate change. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Areas vulnerable to climate change with respect to ca...

  6. Stochastic modeling of carbon oxidation

    SciTech Connect

    Chen, W.Y,; Kulkarni, A.; Milum, J.L.; Fan, L.T.

    1999-12-01

    Recent studies of carbon oxidation by scanning tunneling microscopy indicate that measured rates of carbon oxidation can be affected by randomly distributed defects in the carbon structure, which vary in size. Nevertheless, the impact of this observation on the analysis or modeling of the oxidation rate has not been critically assessed. This work focuses on the stochastic analysis of the dynamics of carbon clusters' conversions during the oxidation of a carbon sheet. According to the classic model of Nagle and Strickland-Constable (NSC), two classes of carbon clusters are involved in three types of reactions: gasification of basal-carbon clusters, gasification of edge-carbon clusters, and conversion of the edge-carbon clusters to the basal-carbon clusters due to the thermal annealing. To accommodate the dilution of basal clusters, however, the NSC model is modified for the later stage of oxidation in this work. Master equations governing the numbers of three classes of carbon clusters, basal, edge and gasified, are formulated from stochastic population balance. The stochastic pathways of three different classes of carbon during oxidation, that is, their means and the fluctuations around these means, have been numerically simulated independently by the algorithm derived from the master equations, as well as by an event-driven Monte Carlo algorithm. Both algorithms have given rise to identical results.

  7. The Structures & Properties of Carbon

    ERIC Educational Resources Information Center

    Castellini, Olivia M.; Lisensky, George C.; Ehrlich, Jennifer; Zenner, Greta M.; Crone, Wendy C.

    2006-01-01

    The four main forms of carbon--diamond, graphite, buckyballs, and carbon nanotubes (CNTs)--are an excellent vehicle for teaching fundamental principles of chemical bonding, material structure, and properties. Carbon atoms form a variety of structures that are intrinsically connected to the properties they exhibit. Educators can take advantage of…

  8. Underwater Acoustic Carbon Nanotube Thermophone

    DTIC Science & Technology

    2016-09-23

    Attorney Docket No. 300042 1 of 10 UNDERWATER ACOUSTIC CARBON NANOTUBE THERMOPHONE STATEMENT OF GOVERNMENT INTEREST [0001] The invention...the Invention [0003] The present invention is an acoustically transparent carbon nanotube underwater acoustic source which acts as a thermophone...development of underwater acoustic carbon nanotube (CNT) yarn sheets capable of producing high acoustic output at low frequencies with broad bandwidth. An

  9. Carbon Nanotube Underwater Acoustic Thermophone

    DTIC Science & Technology

    2016-09-23

    Attorney Docket No. 300009 1 of 8 A CARBON NANOTUBE UNDERWATER ACOUSTIC THERMOPHONE STATEMENT OF GOVERNMENT INTEREST [0001] The...the Invention [0003] The present invention is an acoustically transparent carbon nanotube thermophone. (2) Description of the Prior Art [0004...amplitude of the resulting sound waves. [0006] Recently, there has been development of underwater acoustic carbon nanotube (CNT) yarn sheets capable

  10. Carbon Fiber Risk Analysis. [conference

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The scope and status of the effort to assess the risks associated with the accidental release of carbon/graphite fibers from civil aircraft is presented. Vulnerability of electrical and electronic equipment to carbon fibers, dispersal of carbon fibers, effectiveness of filtering systems, impact of fiber induced failures, and risk methodology are among the topics covered.

  11. The Structures & Properties of Carbon

    ERIC Educational Resources Information Center

    Castellini, Olivia M.; Lisensky, George C.; Ehrlich, Jennifer; Zenner, Greta M.; Crone, Wendy C.

    2006-01-01

    The four main forms of carbon--diamond, graphite, buckyballs, and carbon nanotubes (CNTs)--are an excellent vehicle for teaching fundamental principles of chemical bonding, material structure, and properties. Carbon atoms form a variety of structures that are intrinsically connected to the properties they exhibit. Educators can take advantage of…

  12. The synthesis of organic carbonates from carbon dioxide.

    PubMed

    Sakakura, Toshiyasu; Kohno, Kazufumi

    2009-03-21

    Carbon dioxide (CO(2)) is an easily available, renewable carbon resource, which has the advantages of being non-toxic, abundant and economical. CO(2) is also attractive as an environmentally friendly chemical reagent, and is especially useful as a phosgene substitute. CO(2) is an "anhydrous carbonic acid" that rapidly reacts with basic compounds. Nucleophilic attack at CO(2) conveniently produces carboxyl and carbamoyl groups. Further reactions of these species with electrophiles lead to the formation of organic carbonates and carbamates. The present article deals with the synthetic technologies leading to organic carbonates using CO(2) as a raw material.

  13. Apparatus for producing carbon-coated nanoparticles and carbon nanospheres

    DOEpatents

    Perry, W. Lee; Weigle, John C.; Phillips, Jonathan

    2015-10-20

    An apparatus for producing carbon-coated nano- or micron-scale particles comprising a container for entraining particles in an aerosol gas, providing an inlet for carbon-containing gas, providing an inlet for plasma gas, a proximate torch for mixing the aerosol gas, the carbon-containing gas, and the plasma gas, bombarding the mixed gases with microwaves, and providing a collection device for gathering the resulting carbon-coated nano- or micron-scale particles. Also disclosed is a method and apparatus for making hollow carbon nano- or micro-scale spheres.

  14. Stronger Carbon Fibers for Reinforced Plastics

    NASA Technical Reports Server (NTRS)

    Cagliostro, D. E.; Lerner, N. R.

    1983-01-01

    Process makes fibers 70 percent stronger at lower carbonization temperature. Stronger carbon fibers result from benzoic acid pretreatment and addition of acetylene to nitrogen carbonizing atmosphere. New process also makes carbon fibers of higher electrical resistance -- an important safety consideration.

  15. JaTS: a fully portable seismic tomography software based on Fresnel wavepaths and a probabilistic reconstruction approach

    NASA Astrophysics Data System (ADS)

    Grandjean, Gilles; Sage, Sandrine

    2004-11-01

    JaTS, a Java 2D seismic tomography software, is presented. It implements original algorithms achieving optimal accuracy with reasonable computing costs. A second-order Fast Marching Method (FMM) is used for solving the eikonal equation, therefore enabling a fast and robust computation of seismic traveltimes between sources and receivers. The wavepaths are materialized by Fresnel volumes rather than by conventional rays. This approach accounts for complex velocity models and has the advantage of considering the effects of the wave frequency in the velocity model resolution. The model is computed by a Simultaneous Iterative Reconstruction Technique (SIRT) which has been reformulated to integrate Fresnel wavepaths by using a probabilistic approach. In addition, various utilities are implemented, such as a tapering filter, used to decrease artifact effects occurring in the vicinity of the sources and receivers. The software also offers the possibility of reconstructing the velocity field on a grid larger than the one used for the wave propagation computation. This contributes to stabilize the estimated values. All of the seismic processing tools have been integrated with a user-friendly graphical interface. JaTS represents a tightly integrated tool suite that supports the entire process of importing the SG2 field records, first-break picking, forward modeling and velocity-field computing across multiple platforms.

  16. Carbon and carbon-14 in lunar soil 14163

    SciTech Connect

    Fireman, E.L.; Stoenner, R.W.

    1981-01-01

    Carbon is removed from the surface of lunar soil 14163 size fractions by combustions at 500 and 1000/sup 0/C in an oxygen stream and the carbon contents and the carbon-14 activities are measured. The carbon contents are inversely correlated with grain size. A measured carbon content of 198 ppM for bulk 14163, obtained by combining the size fraction results, is modified to 109 +- 12 ppM by a carbon contamination correction. This value is in accord with a previous determination, 110 ppM, for bulk 14163. The small (< 53 ..mu..) grains of 14163 had more combusted carbon-14 activity, 31.2 +- 2.5 dpm /kg, than the large (> 53 ..mu..) grains, 11.2 +- 2.0 dpm/kg. The combusted carbon and carbon-14 are attributed mainly to solar-wind implantation. Melt extractions of carbon-14 from the combusted soil samples gave essentially identical activities, 21.0 +- 1.5 and 19.2 +- 2.0 dpm/kg for the small and large grains, and are attributed to cosmic-ray spallation-produced carbon-14.

  17. Accelerated carbonation of brucite in mine tailings for carbon sequestration.

    PubMed

    Harrison, Anna L; Power, Ian M; Dipple, Gregory M

    2013-01-02

    Atmospheric CO(2) is sequestered within ultramafic mine tailings via carbonation of Mg-bearing minerals. The rate of carbon sequestration at some mine sites appears to be limited by the rate of CO(2) supply. If carbonation of bulk tailings were accelerated, large mines may have the capacity to sequester millions of tonnes of CO(2) annually, offsetting mine emissions. The effect of supplying elevated partial pressures of CO(2) (pCO(2)) at 1 atm total pressure, on the carbonation rate of brucite [Mg(OH)(2)], a tailings mineral, was investigated experimentally with conditions emulating those at Mount Keith Nickel Mine (MKM), Western Australia. Brucite was carbonated to form nesquehonite [MgCO(3) · 3H(2)O] at a rate that increased linearly with pCO(2). Geochemical modeling indicated that HCO(3)(-) promoted dissolution accelerated brucite carbonation. Isotopic and aqueous chemistry data indicated that equilibrium between CO(2) in the gas and aqueous phases was not attained during carbonation, yet nesquehonite precipitation occurred at equilibrium. This implies CO(2) uptake into solution remains rate-limiting for brucite carbonation at elevated pCO(2), providing potential for further acceleration. Accelerated brucite carbonation at MKM offers the potential to offset annual mine emissions by ~22-57%. Recognition of mechanisms for brucite carbonation will guide ongoing work to accelerate Mg-silicate carbonation in tailings.

  18. Carbon sequestration and its role in the global carbon cycle

    USGS Publications Warehouse

    McPherson, Brian J.; Sundquist, Eric T.

    2009-01-01

    For carbon sequestration the issues of monitoring, risk assessment, and verification of carbon content and storage efficacy are perhaps the most uncertain. Yet these issues are also the most critical challenges facing the broader context of carbon sequestration as a means for addressing climate change. In response to these challenges, Carbon Sequestration and Its Role in the Global Carbon Cycle presents current perspectives and research that combine five major areas: • The global carbon cycle and verification and assessment of global carbon sources and sinks • Potential capacity and temporal/spatial scales of terrestrial, oceanic, and geologic carbon storage • Assessing risks and benefits associated with terrestrial, oceanic, and geologic carbon storage • Predicting, monitoring, and verifying effectiveness of different forms of carbon storage • Suggested new CO2 sequestration research and management paradigms for the future. The volume is based on a Chapman Conference and will appeal to the rapidly growing group of scientists and engineers examining methods for deliberate carbon sequestration through storage in plants, soils, the oceans, and geological repositories.

  19. Graphene oxide assisted hydrothermal carbonization of carbon hydrates.

    PubMed

    Krishnan, Deepti; Raidongia, Kalyan; Shao, Jiaojing; Huang, Jiaxing

    2014-01-28

    Hydrothermal carbonization (HTC) of biomass such as glucose and cellulose typically produces micrometer-sized carbon spheres that are insulating. Adding a very small amount of Graphene oxide (GO) to glucose (e.g., 1:800 weight ratio) can significantly alter the morphology of its HTC product, resulting in more conductive carbon materials with higher degree of carbonization. At low mass loading level of GO, HTC treatment results in dispersed carbon platelets of tens of nanometers in thickness, while at high mass loading levels, free-standing carbon monoliths are obtained. Control experiments with other carbon materials such as graphite, carbon nanotubes, carbon black, and reduced GO show that only GO has significant effect in promoting HTC conversion, likely due to its good water processability, amphiphilicity, and two-dimensional structure that may help to template the initially carbonized materials. GO offers an additional advantage in that its graphene product can act as an in situ heating element to enable further carbonization of the HTC products very rapidly upon microwave irradiation. Similar effect of GO is also observed for the HTC treatment of cellulose.

  20. Carbon Sequestered, Carbon Displaced and the Kyoto Context

    SciTech Connect

    Marland, G.; Schlamadinger, B.

    1999-04-18

    The integrated system that embraces forest management, forest products, and land-use change impacts the global carbon cycle - and hence the net emission of the greenhouse gas carbon dioxide - in four fundamental ways. Carbon is stored in living and dead biomass, carbon is stored in wood products and landfills, forest products substitute in the market place for products made from other materials, and forest harvests can be used wholly or partially to displace fossil fuels in the energy sector. Implementation of the Kyoto Protocol to the United Nations Framework Convention on Climate Change would result in the creation of international markets for carbon dioxide emissions credits, but the current Kyoto text does not treat all carbon identically. We have developed a carbon accounting model, GORCAM, to examine a variety of scenarios for land management and the production of forest products. In this paper we explore, for two simple scenarios of forest management, the carbon flows that occur and how these might be accounted for under the Kyoto text. The Kyoto protocol raises questions about what activities can result in emissions credits, which carbon reservoirs will be counted, who will receive the credits, and how much credit will be available? The Kyoto Protocol would sometimes give credits for carbon sequestered, but it would always give credits when fossil-fuel carbon dioxide emissions are displaced.

  1. A metallic carbon consisting of helical carbon triangle chains.

    PubMed

    Hu, Meng; Dong, Xiao; Pan, Yilong; Xu, Bo; Yu, Dongli; He, Julong

    2014-06-11

    Carbon is the basis of life on Earth and many technological applications. We computationally report an sp3-hybridization-assembled carbon allotrope constructed by helical triangle chains through the evolutionary structure prediction method. Different from the previous metallic carbon K4, this carbon, called Tri-carbon, is mechanically and dynamically stable at ambient pressure. High ring strain in the carbon triangle blocks forces the C–C bond in Tri-carbon to be a 'bent bond', rather than the common single bond in diamond or the π bond in graphite. Unlike the unstrained sp3-hybridization in semiconductive diamond, valence electrons in the 'bent bond' are recombined to form extremely anisotropic sp3-hybridized bonds, thus conferring metallicity to Tri-carbon. Under nonhydrostatic conditions, Tri-carbon shows significantly anisotropic ideal tensile and compressive strength. Tri-carbon is expected to be achieved through chemical methods, such as the synthesis of cyclopropane derivatives (e.g. triangulane and tetrahedrane). These methods eliminate the restriction of ultra-high pressure to obtain metallic carbons.

  2. Thermodynamic assessment of microencapsulated sodium carbonate slurry for carbon capture

    SciTech Connect

    Stolaroff, Joshuah K.; Bourcier, William L.

    2014-01-01

    Micro-encapsulated Carbon Sorbents (MECS) are a new class of carbon capture materials consisting of a CO₂- absorbing liquid solvent contained within solid, CO₂-permeable, polymer shells. MECS enhance the rate of CO₂ absorption for solvents with slow kinetics and prevent solid precipitates from scaling and fouling equipment, two factors that have previously limited the use of sodium carbonate solution for carbon capture. Here, we examine the thermodynamics of sodium carbonate slurries for carbon capture. We model the vapour-liquid-solid equilibria of sodium carbonate and find several features that can contribute to an energy-efficient capture process: very high CO₂ pressures in stripping conditions, relatively low water vapour pressures in stripping conditions, and good swing capacity. The potential energy savings compared with an MEA system are discussed.

  3. Thermodynamic assessment of microencapsulated sodium carbonate slurry for carbon capture

    DOE PAGES

    Stolaroff, Joshuah K.; Bourcier, William L.

    2014-01-01

    Micro-encapsulated Carbon Sorbents (MECS) are a new class of carbon capture materials consisting of a CO₂- absorbing liquid solvent contained within solid, CO₂-permeable, polymer shells. MECS enhance the rate of CO₂ absorption for solvents with slow kinetics and prevent solid precipitates from scaling and fouling equipment, two factors that have previously limited the use of sodium carbonate solution for carbon capture. Here, we examine the thermodynamics of sodium carbonate slurries for carbon capture. We model the vapour-liquid-solid equilibria of sodium carbonate and find several features that can contribute to an energy-efficient capture process: very high CO₂ pressures in stripping conditions,more » relatively low water vapour pressures in stripping conditions, and good swing capacity. The potential energy savings compared with an MEA system are discussed.« less

  4. Development of a carbon formation reactor for carbon dioxide reduction

    NASA Technical Reports Server (NTRS)

    Noyes, G.

    1985-01-01

    Applied research, engineering development, and performance evaluation were conducted on a process for formation of dense carbon by pyrolysis of methane. Experimental research showed that dense (0.7 to 1.6 g/cc bulk density and 1.6 to 2.2 g/cc solid density) carbon can be produced by methane pyrolysis in quartzwool-packed quartz tubes at temperatrues of 1100 to 1300 C. This result supports the condensation theory of pyrolytic carbon formation from gaseous hydrocarbons. A full-scale Breadboard Carbon Formation Reactor (CFR) was designed, fabricated, and tested at 1100 to 1200 C with 380 to 2280 sccm input flows of methane. Single-pass conversion of methane to carbon ranged from 60 to 100 percent, with 89 percent average conversion. Performance was projected for an Advanced Carbon Reactor Subsystem (ACRS) which indicated that the ACRS is a viable option for management of metabolic carbon on long-duration space missions.

  5. Erosion of soil organic carbon: implications for carbon sequestration

    USGS Publications Warehouse

    Van Oost, Kristof; Van Hemelryck, Hendrik; Harden, Jennifer W.; McPherson, B.J.; Sundquist, E.T.

    2009-01-01

    Agricultural activities have substantially increased rates of soil erosion and deposition, and these processes have a significant impact on carbon (C) mineralization and burial. Here, we present a synthesis of erosion effects on carbon dynamics and discuss the implications of soil erosion for carbon sequestration strategies. We demonstrate that for a range of data-based parameters from the literature, soil erosion results in increased C storage onto land, an effect that is heterogeneous on the landscape and is variable on various timescales. We argue that the magnitude of the erosion term and soil carbon residence time, both strongly influenced by soil management, largely control the strength of the erosion-induced sink. In order to evaluate fully the effects of soil management strategies that promote carbon sequestration, a full carbon account must be made that considers the impact of erosion-enhanced disequilibrium between carbon inputs and decomposition, including effects on net primary productivity and decomposition rates.

  6. Liner protected carbon-carbon heat pipe concept

    NASA Astrophysics Data System (ADS)

    Rovang, Richard D.; Hunt, Maribeth E.

    1992-01-01

    A lightweight, high performance radiator concept using carbon-carbon heat pipes is being developed to support space nuclear power applications, specifically the SP-100 system. Carbon-carbon has been selected as an outer structural tube member because of its high temperature and strength characteristics; however, this material must be protected from the potassium heat pipe working fluid. A metallic liner approach is being taken to provide this fluid barrier. Feasibility issues associated with this approach include materials compatibility, fabricastion of the thin-walled liner, bonding the liner to the carbon-carbon tube, mismatch of coefficient of thermal expansion (CTE), carbon diffusion, and end cap closures. To resolve these issues, a series of test coupons have been fabricated and tested, assessing various liner materials, braze alloys, and substrate precursors. These tests will lead to a final heat pipe architecture, material selection, and component assembly.

  7. CARBON DIOXIDE SEPARATION BY SELECTIVE PERMEATION.

    DTIC Science & Technology

    CARBON DIOXIDE , SEPARATION), (*PERMEABILITY, CARBON DIOXIDE ), POROUS MATERIALS, SILICON COMPOUNDS, RUBBER, SELECTION, ADSORPTION, TEMPERATURE, PRESSURE, POLYMERS, FILMS, PLASTICS, MEMBRANES, HUMIDITY.

  8. Carbon Capture and Storage, 2008

    SciTech Connect

    2009-03-19

    The U.S. Department of Energy is researching the safe implementation of a technology called carbon sequestration, also known as carbon capture and storage, or CCS. Based on an oilfield practice, this approach stores carbon dioxide, or CO2 generated from human activities for millennia as a means to mitigate global climate change. In 2003, the Department of Energys National Energy Technology Laboratory formed seven Regional Carbon Sequestration Partnerships to assess geologic formations suitable for storage and to determine the best approaches to implement carbon sequestration in each region. This video describes the work of these partnerships.

  9. Carbon dioxide dangers demonstration model

    USGS Publications Warehouse

    Venezky, Dina; Wessells, Stephen

    2010-01-01

    Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

  10. Carbon Capture and Storage, 2008

    ScienceCinema

    None

    2016-07-12

    The U.S. Department of Energy is researching the safe implementation of a technology called carbon sequestration, also known as carbon capture and storage, or CCS. Based on an oilfield practice, this approach stores carbon dioxide, or CO2 generated from human activities for millennia as a means to mitigate global climate change. In 2003, the Department of Energys National Energy Technology Laboratory formed seven Regional Carbon Sequestration Partnerships to assess geologic formations suitable for storage and to determine the best approaches to implement carbon sequestration in each region. This video describes the work of these partnerships.

  11. Carbon dioxide absorption methanol process

    SciTech Connect

    Apffel, F.

    1989-08-29

    This patent describes a process for removing carbon dioxide from a feed stream of natural gas having at least methane, ethane and heavier. It comprises: first, separating the feed stream in a first separator to form a first stream having substantially all of the propane and heavier hydrocarbons and carbon dioxide and ethane and a second stream, having methane, carbon dioxide and ethane; separating the second stream in a second separator into a stream of carbon dioxide product and a third stream having ethane, methane and carbon dioxide: mixing at least a portion of the third stream with a polar compound; stream after the mixing in an absorber; separating the vapor and liquid of the third stream after the mixing in an absorber; absorbing the remaining unabsorbed carbon dioxide in a lean portion of the polar compound in the absorber, the absorber carbon dioxide and ethane with the polar; separating the first stream in a third separator to separate the propane and heavier hydrocarbons from the carbon dioxide and ethane, which carbon dioxide and ethane forms a fifth stream; and separating the polar compound/carbon dioxide effluent of the absorber in a fourth separator, to separate the carbon dioxide from the polar compound, the polar compound forming a sixth stream.

  12. Global carbon budget 2013

    NASA Astrophysics Data System (ADS)

    Le Quéré, C.; Peters, G. P.; Andres, R. J.; Andrew, R. M.; Boden, T.; Ciais, P.; Friedlingstein, P.; Houghton, R. A.; Marland, G.; Moriarty, R.; Sitch, S.; Tans, P.; Arneth, A.; Arvanitis, A.; Bakker, D. C. E.; Bopp, L.; Canadell, J. G.; Chini, L. P.; Doney, S. C.; Harper, A.; Harris, I.; House, J. I.; Jain, A. K.; Jones, S. D.; Kato, E.; Keeling, R. F.; Klein Goldewijk, K.; Körtzinger, A.; Koven, C.; Lefèvre, N.; Omar, A.; Ono, T.; Park, G.-H.; Pfeil, B.; Poulter, B.; Raupach, M. R.; Regnier, P.; Rödenbeck, C.; Saito, S.; Schwinger, J.; Segschneider, J.; Stocker, B. D.; Tilbrook, B.; van Heuven, S.; Viovy, N.; Wanninkhof, R.; Wiltshire, A.; Zaehle, S.; Yue, C.

    2013-11-01

    Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe datasets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil-fuel combustion and cement production (EFF) are based on energy statistics, while emissions from Land-Use Change (ELUC), including deforestation, are based on combined evidence from land-cover change data, fire activity in regions undergoing deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (GATM) is computed from the annual changes in concentration. The mean ocean CO2 sink (SOCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. The variability in SOCEAN is evaluated for the first time in this budget with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (SLAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of Dynamic Global Vegetation Models. All uncertainties are reported as ± 1 sigma, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2003-2012), EFF was 8.6 ± 0.4 GtC yr-1, ELUC 0.8 ± 0.5 GtC yr-1, GATM 4.3 ± 0.1 GtC yr-1, SOCEAN 2.6 ± 0.5 GtC yr-1, and SLAND 2.6 ± 0.8 GtC yr-1. For year 2012 alone, EFF grew to 9.7

  13. Carbon nanotube biosensors

    PubMed Central

    Tîlmaciu, Carmen-Mihaela; Morris, May C.

    2015-01-01

    Nanomaterials possess unique features which make them particularly attractive for biosensing applications. In particular, carbon nanotubes (CNTs) can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical, and optical characteristics properties which make them one of the best suited materials for the transduction of signals associated with the recognition of analytes, metabolites, or disease biomarkers. Here we provide a comprehensive review on these carbon nanostructures, in which we describe their structural and physical properties, functionalization and cellular uptake, biocompatibility, and toxicity issues. We further review historical developments in the field of biosensors, and describe the different types of biosensors which have been developed over time, with specific focus on CNT-conjugates engineered for biosensing applications, and in particular detection of cancer biomarkers. PMID:26579509

  14. Carbon Fiber Composites

    NASA Technical Reports Server (NTRS)

    1997-01-01

    HyComp(R), Inc. development a line of high temperature carbon fiber composite products to solve wear problems in the harsh environment of steel and aluminum mills. WearComp(R), self-lubricating composite wear liners and bushings, combines carbon graphite fibers with a polyimide binder. The binder, in conjunction with the fibers, provides the slippery surface, one that demands no lubrication, yet wears at a very slow rate. WearComp(R) typically lasts six to ten times longer than aluminum bronze. Unlike bronze, WearComp polishes the same surface and imparts a self-lube film for years of service. It is designed for continuous operation at temperatures of 550 degrees Fahrenheit and can operate under high compressive loads.

  15. Carbon Monoxide Targeting Mitochondria

    PubMed Central

    Queiroga, Cláudia S. F.; Almeida, Ana S.; Vieira, Helena L. A.

    2012-01-01

    Mitochondria present two key roles on cellular functioning: (i) cell metabolism, being the main cellular source of energy and (ii) modulation of cell death, by mitochondrial membrane permeabilization. Carbon monoxide (CO) is an endogenously produced gaseoustransmitter, which presents several biological functions and is involved in maintaining cell homeostasis and cytoprotection. Herein, mitochondrion is approached as the main cellular target of carbon monoxide (CO). In this paper, two main perspectives concerning CO modulation of mitochondrial functioning are evaluated. First, the role of CO on cellular metabolism, in particular oxidative phosphorylation, is discussed, namely, on: cytochrome c oxidase activity, mitochondrial respiration, oxygen consumption, mitochondrial biogenesis, and general cellular energetic status. Second, the mitochondrial pathways involved in cell death inhibition by CO are assessed, in particular the control of mitochondrial membrane permeabilization. PMID:22536507

  16. Depositing Diamondlike Carbon Films

    NASA Technical Reports Server (NTRS)

    Mirtich, M. J.; Sovey, J. S.; Banks, B. A.

    1986-01-01

    New process demonstrated to make thin films (usually thousands of angstroms to few microns thick) that have properties of diamonds. Various plasma and ion-beam techniques employed to generate films. Films made by radio-frequency plasma decomposition of hydrocarbon gas or other alkanes, by low-energy carbon-ion-beam deposition, or by ion plating and dual ion technique using carbon target. Advantages of new process over others are films produced, though amorphous, are clear, extremely hard, chemically inert, of high resistivity, and have index of refraction of 3.2 properties similar to those of single-crystal diamonds. Films have possible uses in microelectronic applications, high-energy-laser and plastic windows, corrosion protection for metals, and other applications where desired properties of film shaped during the film-formation process.

  17. Analysis of carbon monoxide.

    PubMed

    Widdop, Brian

    2002-07-01

    The degree of exposure to carbon monoxide is most often assessed by measuring the blood carboxyhaemoglobin saturation. This measurement is relevant to investigations of acute accidental or deliberate poisoning and of chronic exposure in a domestic or work place environment. Simple spectrophotometric methods based on differential protein precipitation or dithionite reduction are prone to interference from other haemoglobin pigments and are imprecise for low-level estimations. Automated spectrophotometric devices (CO-oximeters) that estimate simultaneously total haemoglobin, percentage oxyhaemoglobin and percentage carboxyhaemoglobin have acceptable accuracy for carboxyhaemoglobin saturation levels of > 5% and are recommended for most clinical purposes. For the investigation of low-level exposure and the detection of increased haemolysis in neonates, more sensitive methods involving the release of carbon monoxide and its measurement by gas chromatography are required. Gas chromatographic methods are also appropriate when examining post-mortem blood samples where putrefaction or heat stress has resulted in a significant change in haemoglobin composition.

  18. Carbon Nanotube Biosensors

    NASA Astrophysics Data System (ADS)

    Tilmaciu, Carmen-Mihaela; Morris, May

    2015-10-01

    Nanomaterials possess unique features which make them particularly attractive for biosensing applications. In particular Carbon Nanotubes (CNTs) can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical and optical characteristics properties which make them one of the best suited materials for the transduction of signals associated with the recognition of analytes, metabolites or disease biomarkers. Here we provide a comprehensive review on these carbon nanostructures, in which we will describe their structural and physical properties, discuss functionalization and cellular uptake, biocompatibility and toxicity issues. We further review historical developments in the field of biosensors, and describe the different types of biosensors which have been developed over time, with specific focus on CNT-conjugates engineered for biosensing applications, and in particular detection of cancer biomarkers.

  19. Applications of Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Ajayan, Pulickel M.; Zhou, Otto Z.

    Carbon nanotubes have attracted the fancy of many scientists worldwide. The small dimensions, strength and the remarkable physical properties of these structures make them a very unique material with a whole range of promising applications. In this review we describe some of the important materials science applications of carbon nanotubes. Specifically we discuss the electronic and electrochemical applications of nanotubes, nanotubes as mechanical reinforcements in high performance composites, nanotube-based field emitters, and their use as nanoprobes in metrology and biological and chemical investigations, and as templates for the creation of other nanostructures. Electronic properties and device applications of nanotubes are treated elsewhere in the book. The challenges that ensue in realizing some of these applications are also discussed from the point of view of manufacturing, processing, and cost considerations.

  20. California's Future Carbon Flux

    NASA Astrophysics Data System (ADS)

    Xu, L.; Pyles, R. D.; Paw U, K.; Gertz, M.

    2008-12-01

    The diversity of the climate and vegetation systems in the state of California provides a unique opportunity to study carton dioxide exchange between the terrestrial biosphere and the atmosphere. In order to accurately calculate the carbon flux, this study couples the sophisticated analytical surface layer model ACASA (Advance Canopy-Atmosphere-Soil Algorithm, developed in the University of California, Davis) with the newest version of mesoscale model WRF (the Weather Research & Forecasting Model, developed by NCAR and several other agencies). As a multilayer, steady state model, ACASA incorporates higher-order representations of vertical temperature variations, CO2 concentration, radiation, wind speed, turbulent statistics, and plant physiology. The WRF-ACASA coupling is designed to identify how multiple environmental factors, in particularly climate variability, population density, and vegetation distribution, impact on future carbon cycle prediction across a wide geographical range such as in California.