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1

Thermal Decomposition of Lanthanide, Yttrium, and Scandium Oxalates and Carbonates  

NASA Astrophysics Data System (ADS)

Data concerning the thermal decomposition of lanthanide, yttrium, and scandium oxalates and carbonates are surveyed. The complexity of the process, the large number of stages involved, and the dependence of the composition of the intermediates in the thermal transformations on the experimental conditions is noted. Certain process characteristics have been discovered and it is concluded that the decomposition process depends on the ionic radius of the metal. The bibliography includes 83 references.

Sharov, Vyacheslav A.; Bezdenezhnykh, G. V.

1981-07-01

2

Author's personal copy Deposition of yttrium oxide thin films in supercritical carbon dioxide  

E-print Network

Author's personal copy Deposition of yttrium oxide thin films in supercritical carbon dioxide 2007 Available online 4 March 2008 Abstract A synthetic avenue for the formation of yttrium oxide thin,5-heptanedionato) yttrium(III) with inorganic (H2O2) and organic (tert-butyl and di-tert-amyl) peroxides

Gougousi, Theodosia

3

RBS and GAXRD contributions to yttrium implanted extra low carbon steel characterization  

SciTech Connect

Extra low carbon steel samples were yttrium implanted using an ion implantation method. Composition and structural studies were carried out before and after yttrium implantations by several analytical and structural techniques (Rutherford backscattering spectrometry, reflection high energy electron diffraction, scanning electron microscopy, X-ray diffraction, and glancing angle X-ray diffraction) to characterize the yttrium implantation effect on extra low carbon steel. The aim of this article is to show the contributions of Rutherford back-scattering spectrometry (RBS) and glancing angle X-ray diffraction (GAXRD) to the determination of yttrium depth profiles in the samples. The results obtained by these techniques are compared to those of the other analyses performed in this work to show the existing correlation between composition and structural studies. Their results allow a better understanding of the effect of yttrium implantation in extra low carbon steel before studying their corrosion resistance at high temperature.

Caudron, E.; Buscail, H. [Equipe Locale Univ. Blaise Pascal Clermont-Fd II, Le Puy en Velay (France). Lab. Vellave d`Elaboration et d`Etude des Materiaux] [Equipe Locale Univ. Blaise Pascal Clermont-Fd II, Le Puy en Velay (France). Lab. Vellave d`Elaboration et d`Etude des Materiaux; Jacob, Y.P.; Stroosnijder, M.F. [European Commission, Ispra (Italy). Inst. for Advanced Materials] [European Commission, Ispra (Italy). Inst. for Advanced Materials

1999-02-01

4

EXTRACTION OF YTTRIUM AND RARE-EARTH ELEMENTS FROM A EUXENITE CARBONATE RESIDUE  

Microsoft Academic Search

Three comparatively simple, efficient, and rapid extraction methods for ; the dissolution of yttrium and rare-earth elements from a euxenite carbonate ; residue have been developed, using dilute sulfuric acid as the solvent. ; Extraction processes have resulted in yields of 98+ % of the total rare-earth ; elements and yttrium contained in the residue and have given preliminary ;

V. E. Shaw; D. J. Bauer; J. M. Gomes

1959-01-01

5

Dye adsorption on mesoporous activated carbon fiber obtained from pitch containing yttrium complex  

Microsoft Academic Search

The adsorption of acid dyes (Acid Blue 9, Acid Blue 74, Acid Orange 10, and Acid Orange 51), direct dyes (Direct Black 19, Direct Yellow 11, and Direct Yellow 50), and basic dyes (Basic Brown 1 and Basic Violet 3) on a highly mesoporous activated carbon fiber (Y-ACF) obtained from pitch containing yttrium acetylacetonate was investigated in terms of size

Hisashi Tamai; Takeshi Yoshida; Masahiko Sasaki

1999-01-01

6

Removal of arsenite and arsenate ions from aqueous solution by basic yttrium carbonate  

Microsoft Academic Search

A new method has been developed to remove arsenite and arsenate ions from aquatic systems by using basic yttrium carbonate (BYC). Various parameters such as pH, anion concentration and reaction time were studied to establish optimum conditions. The removal by adsorption of arsenite and arsenate ions was found to be > 99% depending on initial concentration in the pH range

Syed A. Wasay; Akira Uchiumi; Shuzo Tokunaga

1996-01-01

7

Comparison of the erbium-yttrium aluminum garnet and carbon dioxide lasers for in vitro bone and cartilage ablation  

SciTech Connect

The in vitro bone- and cartilage-ablation characteristics of the solid-state erbium:yttrium aluminum garnet laser were compared to those of the carbon dioxide laser. Ablations of fresh, frozen cadaver septal cartilage and maxillary sinus bone were performed using total energies between 1 and 6 J. Specimens were studied using hematoxylin and eosin stain and digitized, computer-assisted measurements of 35-mm photographs. Erbium-yttrium aluminum garnet-ablated bone averaged 5 microns of adjacent tissue thermal injury, compared with 67 microns with carbon dioxide-ablated bone. Erbium-yttrium aluminum garnet-ablated cartilage averaged 2 microns of adjacent tissue thermal injury, compared with 21 microns with the carbon dioxide-ablated cartilage. The tissue-ablation characteristics of the erbium-yttrium aluminum garnet laser are promising for future otolaryngologic applications.

Gonzalez, C.; van de Merwe, W.P.; Smith, M.; Reinisch, L. (Uniformed Services Univ. of the Health Sciences, Bethesda, MD (USA))

1990-01-01

8

doi:10.1016/S0016-7037(03)00495-2 Carbonate Complexation of Yttrium and the Rare Earth Elements in Natural Waters  

E-print Network

doi:10.1016/S0016-7037(03)00495-2 Carbonate Complexation of Yttrium and the Rare Earth Elements June 23, 2003) Abstract--Potentiometric measurements of Yttrium and Rare Earth Element (YREE.36), (Lu, 2.58, 7.29). Copyright © 2004 Elsevier Ltd 1. INTRODUCTION The environmental behavior of Yttrium

Meyers, Steven D.

9

PET Imaging of Soluble Yttrium-86-Labeled Carbon Nanotubes in Mice  

PubMed Central

Background The potential medical applications of nanomaterials are shaping the landscape of the nanobiotechnology field and driving it forward. A key factor in determining the suitability of these nanomaterials must be how they interface with biological systems. Single walled carbon nanotubes (CNT) are being investigated as platforms for the delivery of biological, radiological, and chemical payloads to target tissues. CNT are mechanically robust graphene cylinders comprised of sp2-bonded carbon atoms and possessing highly regular structures with defined periodicity. CNT exhibit unique mechanochemical properties that can be exploited for the development of novel drug delivery platforms. In order to evaluate the potential usefulness of this CNT scaffold, we undertook an imaging study to determine the tissue biodistribution and pharmacokinetics of prototypical DOTA-functionalized CNT labeled with yttrium-86 and indium-111 (86Y-CNT and 111In-CNT, respectively) in a mouse model. Methodology and Principal Findings The 86Y-CNT construct was synthesized from amine-functionalized, water-soluble CNT by covalently attaching multiple copies of DOTA chelates and then radiolabeling with the positron-emitting metal-ion, yttrium-86. A gamma-emitting 111In-CNT construct was similarly prepared and purified. The constructs were characterized spectroscopically, microscopically, and chromatographically. The whole-body distribution and clearance of yttrium-86 was characterized at 3 and 24 hours post-injection using positron emission tomography (PET). The yttrium-86 cleared the blood within 3 hours and distributed predominantly to the kidneys, liver, spleen and bone. Although the activity that accumulated in the kidney cleared with time, the whole-body clearance was slow. Differential uptake in these target tissues was observed following intraveneous or intraperitoneal injection. Conclusions The whole-body PET images indicated that the major sites of accumulation of activity resulting from the administration of 86Y-CNT were the kidney, liver, spleen, and to a much less extent the bone. Blood clearance was rapid and could be beneficial in the use of short-lived radionuclides in diagnostic applications. PMID:17878942

Jaggi, Jaspreet S.; Finn, Ronald D.; Zanzonico, Pat B.; Villa, Carlos; Rey, Diego; Mendenhall, Juana; Batt, Carl A.; Njardarson, Jon T.; Scheinberg, David A.

2007-01-01

10

In situ high-temperature X-ray diffraction characterization of yttrium-implanted extra low-carbon steel  

SciTech Connect

Yttrium-implanted and unimplanted extra low-carbon steel samples were analyzed at T = 700 C and under an oxygen partial pressure P{sub O2} = 0.041Pa for 24 h to show the yttrium implantation effect on extra low-carbon steel high-temperature corrosion resistance. Sample oxidation weight gains were studied by thermogravimetry, and structural analyses were performed using in situ high-temperature X-ray diffraction with the same experimental conditions. The aim of this paper is to show the initial nucleation stage of the main compounds induced by oxidation at high temperatures according to the initial sample treatment (yttrium-implanted or unimplanted). The results obtained by in situ high-temperature X-ray diffraction will be compared to those by thermogravimetry to show the existing correlation between weight gain curves and structural studies. Results allow one to understand the improved corrosion resistance of yttrium-implanted extra low-carbon steel at high temperatures.

Caudron, E.; Buscail, H.; Perrier, S.

1999-11-01

11

Yttrium-Iron-Garnet as a molten carbonate fuel cell cathode  

SciTech Connect

Yttrium iron garnets (YIG), Y{sub 3}FO{sub 5}0{sub 12} barium ferrite, BaFe{sub l2}O{sub l9}, were synthesized and characterized as alternate molten carbonate fuel cell cathode materials. Doping and calcining conditions were established to synthesize phase pure doped YIG. The conductivity of singly doped YIG was found to be lower than that of lithiated NiO. The performance of singly doped YIG cathode in an in-cell test at the Institute of Gas Technology was below the current NiO cathode due to high polarization loss. Doubly doped compositions were synthesized and characterized. A second dopant was identified and optimized to achieve a conductivity value comparable to lithiated NiO. The advanced composition also exhibited improved corrosion characteristics at 10 atm pressure under cathode gas conditions. A barium ferrite based magnetoplumbite material was tested as a potential cathode candidate in molten carbonate. The material formed a reaction product that was conductive at room temperature; it also exhibited some magnetization. The reaction product was characterized to have Fe{sub 2}O{sub 3} structure. Attempts to synthesize single phase Ba-doped Fe{sub 2}O{sub 3} was unsuccessful. The doped YIG material appears to provide the solutions to two problems that currently limit the MCFC performance and life, namely, cathode stability in the melt and high conductivity in the oxidant atmosphere.

Khandkar, A. (Ceramatec, Inc., Salt Lake City, UT (United States))

1992-09-01

12

High-performance carbon-nanotube-based complementary field-effect-transistors and integrated circuits with yttrium oxide  

NASA Astrophysics Data System (ADS)

High-performance p-type carbon nanotube (CNT) transistors utilizing yttrium oxide as gate dielectric are presented by optimizing oxidization and annealing processes. Complementary metal-oxide-semiconductor (CMOS) field-effect-transistors (FETs) are then fabricated on CNTs, and the p- and n-type devices exhibit symmetrical high performances, especially with low threshold voltage near to zero. The corresponding CMOS CNT inverter is demonstrated to operate at an ultra-low supply voltage down to 0.2 V, while displaying sufficient voltage gain, high noise margin, and low power consumption. Yttrium oxide is proven to be a competitive gate dielectric for constructing high-performance CNT CMOS FETs and integrated circuits.

Liang, Shibo; Zhang, Zhiyong; Si, Jia; Zhong, Donglai; Peng, Lian-Mao

2014-08-01

13

High-performance carbon-nanotube-based complementary field-effect-transistors and integrated circuits with yttrium oxide  

SciTech Connect

High-performance p-type carbon nanotube (CNT) transistors utilizing yttrium oxide as gate dielectric are presented by optimizing oxidization and annealing processes. Complementary metal-oxide-semiconductor (CMOS) field-effect-transistors (FETs) are then fabricated on CNTs, and the p- and n-type devices exhibit symmetrical high performances, especially with low threshold voltage near to zero. The corresponding CMOS CNT inverter is demonstrated to operate at an ultra-low supply voltage down to 0.2?V, while displaying sufficient voltage gain, high noise margin, and low power consumption. Yttrium oxide is proven to be a competitive gate dielectric for constructing high-performance CNT CMOS FETs and integrated circuits.

Liang, Shibo; Zhang, Zhiyong, E-mail: zyzhang@pku.edu.cn; Si, Jia; Zhong, Donglai; Peng, Lian-Mao, E-mail: lmpeng@pku.edu.cn [Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University, Beijing 100871 (China)

2014-08-11

14

Correlation of optical properties and temperature-induced irreversible phase transitions in europium-doped yttrium carbonate nanoparticles  

SciTech Connect

Nanophase europium-doped yttrium carbonate precursors are subjected to heat treatments, ranging from 300 Degree-Sign C to 1100 Degree-Sign C for dwell times of 5 min, 30 min, and 180 min. XRD, TEM, FT-IR, fluorescence, fluorescence excitation, and fluorescence lifetime measurements are used to characterize the materials. Upon heating, the material transitions through several amorphous stages until it reaches the crystalline cubic Y{sub 2}O{sub 3} phase. DSC measurements show an exothermic transition at 665.7 Degree-Sign C, indicating the formation of crystalline Y{sub 2}O{sub 3}. The grain size development is fitted by the relaxation equation and yields an activation energy of 50.3 kJ/mol. The amorphous phases are characterized by inhomogenously broadened optical spectra. Heating up to 700 Degree-Sign C leads to an increased fluorescence lifetime (from about 1 ms to 2.4 ms). As the material is heated to higher temperatures and completes the formation of the crystalline cubic Y{sub 2}O{sub 3} phase, the optical spectra become narrower and the fluorescence lifetime decreases to about 1.2 ms. - Graphical abstract: Fluorescence lifetimes of Eu-doped Y{sub 2}O{sub 3} precursors heated for 5, 30, and 180 min to various temperatures. Highlights: Black-Right-Pointing-Pointer Irreversible phase transitions in nanoparticles are of interest for thermometry. Black-Right-Pointing-Pointer Eu-doped nanophase yttrium carbonate precursors were heat-treated. Black-Right-Pointing-Pointer The material undergoes decomposition and crystallization. Black-Right-Pointing-Pointer Morphological and optical properties are measured. Black-Right-Pointing-Pointer Optical properties can be used to deduce the temperature.

Gunawidjaja, Ray; Myint, Thandar [Applied Sciences Laboratory, Institute for Shock Physics, Washington State University, Spokane, WA 99210-1495 (United States); Eilers, Hergen, E-mail: eilers@wsu.edu [Applied Sciences Laboratory, Institute for Shock Physics, Washington State University, Spokane, WA 99210-1495 (United States)

2011-12-15

15

Synergistic effects of sequential carbon dioxide and neodymium:yttrium aluminum garnet laser injuries. Experimental observations and measurements  

SciTech Connect

The carbon dioxide and neodymium:yttrium aluminum garnet lasers have well documented but characteristically different biological effects, yet little is known about their cumulative, synergistic, or paradoxical effects when used sequentially on living tissue. Using a Merrimack ML 880 laser, a series of superimposed CO/sub 2/ and Nd:YAG lesions in various combinations were produced on the undersurface of dog tongues. Therapeutic time and power settings were chosen and the number of applications varied, with suitable controls. Observations and measurements were made on acute, healing, and healed lesions. All lesions were excised and submitted for routine hematoxylin and eosin histology. Acute lesions were also assessed for cell viability using rhodamine 123 as a supravital marker. The results show that, even though all the lesions eventually heal, the actual cell damage produced by the Nd:YAG laser is much more than is suggested by the size of the acute lesion. This cell damage can be reduced by the surface carbonization produced by initial application of the CO/sub 2/ laser. Higher surface temperatures are reached in this combination with less fibrosis and scarring than equal energy counterparts where the Nd:YAG laser was applied first. The knowledge of these synergistic effects can be used to advantage in the clinical setting. The rhodamine 123 technique also appears to be a valid measure of acute thermal tissue injury.

Primrose, W.J.; McDonald, G.A.; O'Brien, M.J.; Vaughan, C.W.; Strong, M.S.

1987-01-01

16

Comparative and quantitative study of neutral debris emanated from tin plasmas produced by neodymium-doped yttrium-aluminum-garnet and carbon dioxide laser pulses  

NASA Astrophysics Data System (ADS)

Amount of neutral debris emanated from extreme ultraviolet light source must be minimized to maximize its lifetime. Emanation of neutral atomic debris was experimentally investigated using laser-induced-fluorescence technique for carbon dioxide (CO2, 10.6 ?m in wavelength) and Nd-doped yttrium-aluminum-garnet (Nd:YAG, 1.064 ?m) lasers irradiated tin foils. Total number of neutral atomic debris from CO2 laser-irradiated tin foils was 1/100 times smaller than that from Nd:YAG irradiated ones. Competitiveness of CO2 laser was revealed in terms of debris mitigation.

Matsuoka, Yuji; Nakai, Yuki; Fujioka, Shinsuke; Maeda, Shinsuke; Shimomura, Masashi; Shimada, Yoshinori; Sunahara, Atsushi; Nishimura, Hiroaki; Yoshida, Minoru

2010-09-01

17

Comparative and quantitative study of neutral debris emanated from tin plasmas produced by neodymium-doped yttrium-aluminum-garnet and carbon dioxide laser pulses  

SciTech Connect

Amount of neutral debris emanated from extreme ultraviolet light source must be minimized to maximize its lifetime. Emanation of neutral atomic debris was experimentally investigated using laser-induced-fluorescence technique for carbon dioxide (CO{sub 2}, 10.6 {mu}m in wavelength) and Nd-doped yttrium-aluminum-garnet (Nd:YAG, 1.064 {mu}m) lasers irradiated tin foils. Total number of neutral atomic debris from CO{sub 2} laser-irradiated tin foils was 1/100 times smaller than that from Nd:YAG irradiated ones. Competitiveness of CO{sub 2} laser was revealed in terms of debris mitigation.

Matsuoka, Yuji; Nakai, Yuki; Fujioka, Shinsuke; Maeda, Shinsuke; Shimomura, Masashi; Nishimura, Hiroaki [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Osaka 565-0871 (Japan); Shimada, Yoshinori; Sunahara, Atsushi [Institute for Laser Technology, Osaka University, 2-6 Yamada-Oka, Osaka 565-0871 (Japan); Yoshida, Minoru [Department of Electronics and Electronic Engineering, Kinki University, 3-4-1 Kowakae, Osaka 577-8502 (Japan)

2010-09-13

18

Carbon nanotubes : synthesis, characterization, and applications  

E-print Network

copper, and yttrium have been used as co-catalysts [178, 438], producing yields of single-walled carbon nanotubescopper TEM grid (Electron Microscopy Sciences, part #FF200-Cu) across the sample, transferring a small quantity of carbon nanotubes

Deck, Christian Peter

2009-01-01

19

Carbon spheres  

Microsoft Academic Search

The discovery of fullerenes has opened up new studies in shaped carbon materials. In particular the discovery that carbon atoms in fullerenes showed curved sp2 bonding also led to the discovery of single walled carbon nanotubes and a re-investigation of carbon fibers and tubes. The area of shaped carbon materials has since been dominated by studies of carbon nanotubes. The

Amit A. Deshmukh; Sabelo D. Mhlanga; Neil J. Coville

2010-01-01

20

Carbon Cycles  

NSDL National Science Digital Library

Students are introduced to the concept of energy cycles by learning about the carbon cycle. They learn how carbon atoms travel through the geological (ancient) carbon cycle and the biological/physical carbon cycle. They consider how human activities disturb the carbon cycle by emitting carbon dioxide into the atmosphere. They discuss how engineers and scientists are working to reduce carbon dioxide emissions. Lastly, students consider how they can help the world through simple energy conservation measures.

2014-09-18

21

carbon cycle  

NSDL National Science Digital Library

Life on earth is based on carbon. Living things acquire carbon from their environment - from air, water, soil, and rock and from other living things - through processes such as photosynthesis, respiration and decomposition. The carbon cycle model is a representation of the movement of carbon from sources to sinks through chemical and physical transfers. The carbon cycle activity allows students to see the effect of fossil fuel burning on the carbon cycle.

Maryland Virtual High School

22

Carbon-carbon cylinder block  

NASA Technical Reports Server (NTRS)

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.

Ransone, Philip O. (Inventor)

1998-01-01

23

Carbon Smackdown: Carbon Capture  

ScienceCinema

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

Jeffrey Long

2010-09-01

24

Carbon Smackdown: Carbon Capture  

SciTech Connect

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

Jeffrey Long

2010-07-12

25

Carbon-carbon piston development  

NASA Technical Reports Server (NTRS)

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.

Gorton, Mark P.

1994-01-01

26

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 ...

27

Carbon Sequestration  

NSDL National Science Digital Library

In this inquiry-based lesson, learners measure the biomass of trees, calculate the carbon stored by the trees, and use this information to create recommendations about using trees for carbon sequestration. This activity encourages learners to think critically about managing forests for carbon sequestration.

New York Hall of Science

2012-01-01

28

Carbon-Carbon Piston Architectures  

NASA Technical Reports Server (NTRS)

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.

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

1999-01-01

29

CARBON MONOXIDE  

EPA Science Inventory

This document summarizes the carbon monoxide literature related to effects on man and his environment for the consideration of the Environmental Protection Agency in updating the information in the Air Quality Criteria for Carbon Monoxide. It emphasizes recent major advances in o...

30

Carbon-Carbon Piston Architectures  

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

31

Carbon Cycle  

NSDL National Science Digital Library

This activity from NOAA Earth System Research Laboratory introduces students to the current scientific understanding of the greenhouse effect and the carbon cycle. The activity leads them through several interactive tasks investigating recent trends in atmospheric carbon dioxide. Students analyze scientific data and use scientific reasoning to determine the causes responsible for these recent trends. By studying carbon cycle science in a visual and interactive manner, the activity provides students with a conceptual framework with which to address the challenges of a changing climate.

NOAA/Earth System Research Laboratory

32

Developments in carbon materials  

NASA Technical Reports Server (NTRS)

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.

Burchell, Timothy D.

1994-01-01

33

Infiltrated carbon foam composites  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

34

Carbon Cycle  

NSDL National Science Digital Library

This interactive animation focuses on the carbon cycle and includes embedded videos and captioned images to provide greater clarification and detail of the cycle than would be available by a single static visual alone.

Sciencelearn

35

Co-Precipitation of Double Carbonates of Yttrium and the Rare Earth Elements, Na2xM2(CO3)3+x, from Seawater-Like Electrolyte Solutions  

NASA Astrophysics Data System (ADS)

Co-precipitation of mixed carbonates of yttrium and the rare earth elements (YREEs) from perchlorate and chloride solutions at seawater ionic strength (0.7 molal, T = 25°C) was induced by raising pH under an atmosphere of 100% CO2. Solution pH was monitored with a glass combination electrode, and dissolved YREE concentrations by ICP-MS after filtration through 0.2 ?m pore size membranes. Experiments were conducted (a) in NaClO4 and NaCl with equimolar YREE mixtures (all 1 mM); (b) in NaClO4 with equimolar YREE mixtures (10 ?M) plus 1 mM Sm; and (c) with pure Sm and Yb solutions (10 mM). The applied pH range (4-8) resulted in a nearly 7 orders of magnitude variation of the free carbonate concentration. Double-logarithmic plots of individual YREE concentrations as a function of the free carbonate concentration are highly linear for all experiments, whereby the slopes represent carbonate:YREE ratios of the saturated solutions in equilibrium with the mixed co-precipitates, for each element. In virtually all cases (except for Y, Yb, and Lu in the equimolar mixture and Lu in the Sm-enriched mixture, both in NaClO4) the observed slopes are significantly larger than 1.5, the value expected for pure YREE carbonates (x = 0). The higher values suggest missing positive charge, which must be supplied by Na+, the only other positive ion in the solutions. Double carbonates of the form NaM(CO3)2 have long been known as the least soluble YREE salts in Na-rich solutions, yet their role in YREE geochemical cycles has been largely ignored. In addition, studies of their solubilities have focused mainly on precipitates of single YREEs, which do not occur in nature. The stoichiometry of the mixed co-precipitates appears quite complicated and variable. The pure Sm and Yb precipitates yield slopes of ~1.6, indicating minor incorporation of Na+. The mixed co-precipitate formed in NaClO4 yields slopes that smoothly vary from ~1.5 for Y and Lu to a maximum of ~1.8 for Sm. In NaCl the slopes are about 0.1 units higher and the maximum is shifted to slightly heavier elements, possibly due to YREE-chloride complexation. In the Sm-enriched co-precipitate the slopes range from ~1.5 for Lu to ~2.0 for Dy, displaying substantially more structure as a function of atomic number. Ion concentration products, calculated from the inferred stoichiometries, are similar in magnitude to published solubility products for the pure carbonates of single YREEs but show distinctly different patterns across the YREE series. These results could have a profound impact on interpretations of the pH-dependent incorporation of YREEs in marine carbonates, such as coral skeletons and pteropod shells, which are generally based on the solubility products of single-YREE carbonates precipitated from Na-free solutions. YREE abundance patterns and Nd isotope ratios in biominerals are likely to be increasingly used in studies of paleo-ocean circulation patterns, coastal inputs of dust due to mining and deforestation, and possibly ocean acidification.

Schijf, J.; Byrne, R. H.

2010-12-01

36

Carbon Temperature Model  

NSDL National Science Digital Library

With this carbon/temperature interactive model, students investigate the role of atmospheric carbon in the greenhouse effect using a relationship between atmospheric carbon dioxide and global temperature.

NASA: Challenger Center

37

Carbon particles  

DOEpatents

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.

Hunt, Arlon J. (Oakland, CA)

1984-01-01

38

Carbon microtubes  

DOEpatents

A carbon microtube comprising a hollow, substantially tubular structure having a porous wall, wherein the microtube has a diameter of from about 10 .mu.m to about 150 .mu.m, and a density of less than 20 mg/cm.sup.3. Also described is a carbon microtube, having a diameter of at least 10 .mu.m and comprising a hollow, substantially tubular structure having a porous wall, wherein the porous wall comprises a plurality of voids, said voids substantially parallel to the length of the microtube, and defined by an inner surface, an outer surface, and a shared surface separating two adjacent voids.

Peng, Huisheng (Shanghai, CN); Zhu, Yuntian Theodore (Cary, NC); Peterson, Dean E. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM)

2011-06-14

39

Frozen Carbon  

NSDL National Science Digital Library

This is a polar map of permafrost extent in the Northern Hemisphere. A sidebar explains how permafrost, as it forms and later thaws, serves as both a sink and source for carbon to the atmosphere. Related multimedia is a slideshow of permafrost scientists from U. of Alaska, Fairbanks, collecting permafrost data in the field.

Jonathan Corum

40

Black Carbon  

NSDL National Science Digital Library

Black carbon, composed of tiny particles of soot, is produced whenever organic substances like fossil fuels, firewood or coal is incompletely burned. These particles are polluting the air and causing serious health and environmental concerns for people around the world. "Changing Planet" is produced in partnership with the National Science Foundation.

NBC Learn

2010-10-07

41

Carbon dioxide  

NSDL National Science Digital Library

Bubbles are an indicator of a chemical reaction. An indicator is an object, material, or organism that tells you if a specific substance is present. In the sugar test, carbon dioxide gas release is an indicator that yeast is using sugar to grow. The more gas produced, the more sugar a specific substance contains.

Arie Melamed-Katz (None; )

2007-06-19

42

Carbon Footprint  

NSDL National Science Digital Library

Students investigate how much greenhouse gas (carbon dioxide and methane) their family releases into the atmosphere each year and relate it to climate change. To address this, students use the Environmental Protection Agency Personal Emissions Calculator to estimate their family's greenhouse gas emissions and to think about how their family could reduce those emissions.

2007-01-01

43

Oxidation protected carbon-carbon  

NASA Technical Reports Server (NTRS)

Pyrolized carbon-carbon has one unique advantage over other materials that makes its application to the space shuttle thermal protection system very attractive. This unique characteristic is the increase in material strength and modulus with increase in temperature up to about 2500 K (4040 F). Offsetting this unique advantage are disadvantages which include brittleness, high cost, and the tendency of the material to react with oxygen, particularly at high temperatures. The development of an oxidation inhibitor for the material and the definition of fabrication processes for selected full-scale components are considered.

Pavlosky, J. E.; St. Leger, L. G.

1972-01-01

44

Molecular Structure of Carbonate ion  

NSDL National Science Digital Library

Carbonates were studied extensively by geologists. Common carbonate-containing geologic materials are barium calcium carbonate, lead carbonate, and strontium carbonate. Carbonate is the salt of carbonic acid. Many counter ions are possible, including calcium carbonate and barium carbonate. Calcium carbonate is a brittle white rock, used in many buildings. Lithium carbonate is used to treat manic phases for bipolar disorder/manic depression. Carbonic acid is found in carbonated beverages, giving them a tart flavor.

2002-09-18

45

Carbon Cycle  

NSDL National Science Digital Library

Elementary students often successfully memorize and repeat back the stages in cycles, with no deep conceptual understanding of the complexities of the processes involved. Their ability to synthesize knowledge of the cycles with a wider breadth of information related to real-world, unresolved environmental issues such as global warming, greenhouse gas emissions or the burning of biomass for fuel is probably less well developed. In order to engage in meaningful discussions of carbon-related environmental issues, students also need an understanding of the changing nature of the earth s atmosphere. The relative proportion of nitrogen, carbon dioxide, oxygen, ozone and other gases is neither consistent around the world nor constant over time. What factors contribute to the variability in atmospheric content? Which of the factors should be controlled? What are the possible approaches to controlling them? What are the possible and probable outcomes of such controlling measures?

Mary LeFever

2007-01-01

46

Carbon Trading, Carbon Taxes and Social Discounting  

E-print Network

Carbon Trading, Carbon Taxes and Social Discounting Elisa Belfiori belf0018@umn.edu University of Minnesota Abstract This paper considers the optimal design of policies to carbon emissions in an economy, such as price or quantity controls on the net emissions of carbon, are insufficient to achieve the social

Weiblen, George D

47

IC Engine Applications of Carbon-Carbon  

NASA Technical Reports Server (NTRS)

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.

Northam, G. Burton; Rivers, H. Kevin

2000-01-01

48

Public Review Draft: A Method for Assessing Carbon Stocks, Carbon  

E-print Network

Public Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse, and Zhu, Zhiliang, 2010, Public review draft; A method for assessing carbon stocks, carbon sequestration

49

Carbon Nanotubes  

NSDL National Science Digital Library

From the NanoEd Resource Portal, this course describes the purpose and uses of carbon nanotubes in etching, indentation, compression, bending, and twisting as well as their application as gears. Instructed by Dr. Meyya Meyyappan and contributed by the NASA Ames Research Center, the main content of this course is the variety of demonstration videos on each topic so visitors may make the nanoscale visible. In total, there are thirty mpg format videos, and each would make an excellent addition to any nanotechnology classroom.

Meyyappan, Meyya

50

Carbon "Kidprints"  

NSDL National Science Digital Library

In this self-paced tutorial, learners explore the personal choices students make every day as resource consumers, and how those decisions contribute to the climate health of our planet. Multimedia educational resources such as video clips, digital interactive explorations and a quiz are included. This is the fifth of ten self-paced professional development modules providing opportunities for teachers to learn about climate change through first-hand data exploration. A carbon consumption calculator designed for kids to be used in the classroom and glossary links to vocabulary are included.

51

Carbon Cycle: Where Is This Crucial Carbon?  

NSDL National Science Digital Library

This demonstration aims to teach students about the nature of carbon, the different types of compounds it exists in (e.g. charcoal, glucose, carbon dioxide), the biochemical reactions it takes part in (photosynthesis and respiration), the range of processes that carbon and carbon compounds are involved in on Earth, and how these link together to form the carbon cycle. Students will be reminded that carbon is the fundamental building block of life (the element that life is based on). They will discover that carbon is contained in everything from fossil fuels to DNA and is cycled and re-cycled through the carbon cycle. Students will also understand that both animals and plants need carbon although they obtain it in different ways. This site has teacher notes and directions, suggested questions with answers, a list of required materials, and a glossary.

52

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...

53

CALIFORNIA CARBON SEQUESTRATION THROUGH  

E-print Network

CALIFORNIA ENERGY COMMISSION CARBON SEQUESTRATION THROUGH CHANGES IN LAND USE IN WASHINGTON. Carbon Sequestration Through Changes in Land Use in Washington: Costs and Opportunities. California for Terrestrial Carbon Sequestration in Oregon. Report to Winrock International. #12;ii #12;iii Preface

54

The Carbon Cycle  

NSDL National Science Digital Library

This narrated slide presentation shows the carbon cycle, looking at various parts of this biogeochemical sequence by examining carbon reservoirs and how carbon is exchanged among them and the atmosphere.

Thinkport

55

Photophysics of carbon nanotubes  

E-print Network

This thesis reviews the recent advances made in optical studies of single-wall carbon nanotubes. Studying the electronic and vibrational properties of carbon nanotubes, we find that carbon nanotubes less than 1 nm in ...

Samsonidze, Georgii G

2007-01-01

56

Low Carbon Fuel Standards  

E-print Network

transitioning to low-carbon alternative transportation fuelsLow-Carbon Fuel Standard for California, Part 2: Policy Analysis. Institute of TransportationLow-Carbon Fuel Standard for California, Part 1: Technical Analysis. Insti- tute of Transportation

Sperling, Dan; Yeh, Sonia

2009-01-01

57

Method of making carbon-carbon composites  

DOEpatents

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.

Engle, Glen B. (16716 Martincoit Rd., Poway, CA 92064)

1993-01-01

58

Interpreting carbon-isotope excursions: carbonates and organic matter  

Microsoft Academic Search

Variations in the carbon isotopic compositions of marine carbonate and organic carbon provide a record of changes in the fraction of organic carbon buried through time and may provide clues to changes in rates of weathering and sources of organic carbon. Paired carbonate and organic carbon isotope determinations provide a possibility of interpreting not only changes in the global carbon

Lee R. Kump; Michael A. Arthur

1999-01-01

59

Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production  

E-print Network

#12;Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward Zero Carbon Energy Production Toward

Narasayya, Vivek

60

Carbon Capture (Carbon Cycle 2.0)  

SciTech Connect

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/

Smit, Berend

2010-02-03

61

Carbon Capture (Carbon Cycle 2.0)  

ScienceCinema

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/

Smit, Berend

2011-06-08

62

Integral Ring Carbon-Carbon Piston  

NASA Technical Reports Server (NTRS)

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.

Northam, G. Burton (Inventor)

1999-01-01

63

Carbon-carbon grid for ion engines  

NASA Technical Reports Server (NTRS)

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.

Garner, Charles E. (inventor)

1993-01-01

64

Carbon-carbon grid for ion engines  

NASA Technical Reports Server (NTRS)

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.

Garner, Charles E. (inventor)

1995-01-01

65

Carbon dioxide sequestration by mineral carbonation  

Microsoft Academic Search

The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept behind mineral CO2 sequestration is the mimicking of natural weathering processes in which calcium or magnesium containing minerals

W. J. J. Huijgen; R. N. J. Comans

2007-01-01

66

Composite carbon foam electrode  

DOEpatents

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.

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

1997-05-06

67

Composite carbon foam electrode  

DOEpatents

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.

Mayer, Steven T. (San Leandro, CA); Pekala, Richard W. (Pleasant Hill, CA); Kaschmitter, James L. (Pleasanton, CA)

1997-01-01

68

From carbon nanotubes to carbon atomic chains  

NASA Astrophysics Data System (ADS)

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.

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

2010-10-01

69

Magnetic carbon.  

PubMed

The discovery of nanostructured forms of molecular carbon has led to renewed interest in the varied properties of this element. Both graphite and C60 can be electron-doped by alkali metals to become superconducting; transition temperatures of up to 52 K have been attained by field-induced hole-doping of C60 (ref. 2). Recent experiments and theoretical studies have suggested that electronic instabilities in pure graphite may give rise to superconducting and ferromagnetic properties, even at room temperature. Here we report the serendipitous discovery of strong magnetic signals in rhombohedral C60. Our intention was to search for superconductivity in polymerized C60; however, it appears that our high-pressure, high-temperature polymerization process results in a magnetically ordered state. The material exhibits features typical of ferromagnets: saturation magnetization, large hysteresis and attachment to a magnet at room temperature. The temperature dependences of the saturation and remanent magnetization indicate a Curie temperature near 500 K. PMID:11607027

Makarova, T L; Sundqvist, B; Höhne, R; Esquinazi, P; Kopelevich, Y; Scharff, P; Davydov, V A; Kashevarova, L S; Rakhmanina, A V

2001-10-18

70

Dynamic carbon footprinting  

Microsoft Academic Search

The early focus by individual businesses on the reduction of their own carbon footprint is being superseded by a phase of building carbon-constrained business networks. Across these networks, businesses evaluate each others' footprints and conduct business accordingly. Dynamic carbon footprinting is emerging as a powerful tool for guiding operational logic and business transformation into the carbon-constrained markets, with delivery of

Michael Gell

2008-01-01

71

Carbon Cycle Diagram  

NSDL National Science Digital Library

This diagram illustrates some of the most abundant stores of carbon and identifies some of the pathways in the carbon cycle along which carbon is transferred from one form to another. Long-term sinks of carbon are labelled in black; shorter-term fluxes are labelled in purple. Amounts are in billions of tons.

72

Acetylenic carbon allotrope  

DOEpatents

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.

Lagow, R.J.

1998-02-10

73

Carbon Journey Game  

NSDL National Science Digital Library

This hands-on activity is a kinesthetic game illustrating the dynamics of the carbon cycle. Acting as carbon atoms, students travel from one carbon reservoir to another; at each reservoir they determine, by rolling dice, how long they stay in the reservoir or how likely it is that they will move to another carbon reservoir.

Andrill

74

Acetylenic carbon allotrope  

DOEpatents

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.

Lagow, Richard J. (6204 Shadow Mountain Dr., Austin, TX 78731)

1998-01-01

75

Acetylenic carbon allotrope  

DOEpatents

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.

Lagow, Richard J. (6204 Shadow Mountain Dr., Austin, TX 78731)

1999-01-01

76

Carbon Cycle Game  

NSDL National Science Digital Library

In this interactive, regionally-relevant carbon cycle game, students are challenged to understand the role of carbon in global climate change. They imagine that they are carbon molecules and travel via different processes through carbon reservoirs on the Colorado Plateau (the Four Corners area of Arizona, Colorado, New Mexico and Utah). This game can be adapted to other regions.

Colorado Plateau Climate Science and Solutions Partnership

77

Pyrolyzed thin film carbon  

NASA Technical Reports Server (NTRS)

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.

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

2010-01-01

78

Mesoporous carbon materials  

DOEpatents

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.

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

2014-09-09

79

Sorption of Carbon Dioxide onto Sodium Carbonate  

Microsoft Academic Search

Sodium carbonate was used as a sorbent to capture CO2 from a gaseous stream of carbon dioxide, nitrogen, and moisture. The breakthrough data of CO2 were measured in a fixed bed to observe the reaction kinetics of CO2?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

2006-01-01

80

Carbon/Carbon extendible Nozzles  

NASA Astrophysics Data System (ADS)

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.

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

2002-03-01

81

Carbon fuel cells with carbon corrosion suppression  

DOEpatents

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.

Cooper, John F. (Oakland, CA)

2012-04-10

82

The Carbon Cycle  

NSDL National Science Digital Library

This Earth Observatory site contains detailed information on the carbon cycle of the Earth. It provides an explanation of the role of carbon in the geologic carbon cycle followed by a discussion of carbon in the life process, including photosynthesis and respiration. Carbon sinks on land and in the ocean are covered next, followed by the human role in the cycle. Lastly, the activity of the National Aeronautics and Space Administration, (NASA), and that of the National Oceanic and Atmospheric Administration, (NOAA) in the exploration of the connection of the carbon cycle to weather and climate is covered.

2011-04-27

83

Metallic carbon materials  

DOEpatents

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.

Cohen, Marvin Lou (Berkeley, CA); Crespi, Vincent Henry (Darien, IL); Louie, Steven Gwon Sheng (Berkeley, CA); Zettl, Alexander Karlwalter (Kensington, CA)

1999-01-01

84

Method of making carbon-carbon composites  

DOEpatents

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.

Engle, Glen B. (16716 Martincoit Rd., Poway, CA 92064)

1991-01-01

85

Sodium carbonate poisoning  

MedlinePLUS

Sodium carbonate (also known as washing soda or soda ash) is a chemical found in many household and ... products. This article focuses on poisoning due to sodium carbonate. This is for information only and not for ...

86

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...

87

Interstellar carbon in meteorites  

NASA Technical Reports Server (NTRS)

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.

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

1983-01-01

88

Carbon nanotube nanoelectrode arrays  

DOEpatents

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.

Ren, Zhifeng (Newton, MA); Lin, Yuehe (Richland, WA); Yantasee, Wassana (Richland, WA); Liu, Guodong (Fargo, ND); Lu, Fang (Burlingame, CA); Tu, Yi (Camarillo, CA)

2008-11-18

89

Biogeochemistry: Old carbon mobilized  

NASA Astrophysics Data System (ADS)

Soil contains aged organic carbon that can be hundreds or thousands of years old. Human disturbance in small and large watersheds is mobilizing some of this fossil carbon from soils to aquatic systems.

Evans, Chris

2015-02-01

90

Carbon Monoxide Safety Tips  

E-print Network

Protect yourself and your family from the deadly effects of carbon monoxide--a colorless, odorless poisonous gas. This publication describes the warning signs of carbon monoxide exposure and includes a home safety checklist....

Shaw, Bryan W.; Garcia, Monica L.

1999-07-26

91

The boundless carbon cycle  

Microsoft Academic Search

The terrestrial biosphere is assumed to take up most of the carbon on land. However, it is becoming clear that inland waters process large amounts of organic carbon and must be considered in strategies to mitigate climate change.

Tom J. Battin; Sebastiaan Luyssaert; Louis A. Kaplan; Anthony K. Aufdenkampe; Andreas Richter; Lars J. Tranvik

2009-01-01

92

ESM 271 Carbon Footprints and Carbon Accounting Instructor: Sangwon Suh  

E-print Network

1 ESM 271 Carbon Footprints and Carbon Accounting Instructor: Sangwon Suh Bren hall 3422, suh: Homework (1 for each week @10%): 40% Personal carbon account (report): 30% Final exam: 30% Course schedule Week 1: Introduction to carbon footprint and carbon account - Background: carbon awareness, major

California at Santa Barbara, University of

93

Carbon/Carbon Pistons for Internal Combustion Engines  

NASA Technical Reports Server (NTRS)

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.

Taylor, A. H.

1986-01-01

94

Carbon Cycle Roleplay  

NSDL National Science Digital Library

In this creative roleplay activity, learners will explore the various processes of the carbon cycle using movement and props to aid in comprehension. Learners will understand that carbon changes forms throughout the carbon cycle, and that carbon is continuously moving throughout all the cycles at the same time. This standards-based lesson, which is great for the classroom, camps, or afterschool programs, includes roleplay cards and ideas for props.

California Academy of Sciences

2008-01-01

95

Understanding the Carbon Cycle  

NSDL National Science Digital Library

In this unit, students use Internet resources, slide presentations, and modeling to explain how understanding the carbon cycle helps scientists understand and prepare for global climate change, what might happen if sources of carbon produced more than sinks could remove, and what might happen if sinks absorbed more than sources produced. They should understand how the carbon cycle affects various life forms and the role that carbon plays in their lives. Procedures, a glossary, assessments, and scoring rubrics are provided.

96

Metal filled porous carbon  

DOEpatents

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.

Gross, Adam F. (Los Angeles, CA); Vajo, John J. (West Hills, CA); Cumberland, Robert W. (Malibu, CA); Liu, Ping (Irvine, CA); Salguero, Tina T. (Encino, CA)

2011-03-22

97

The Contemporary Carbon Cycle  

Microsoft Academic Search

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

R. A. Houghton

2003-01-01

98

Carbon Footprint Towson University  

E-print Network

Carbon Footprint Towson University GHG Inventory for Educational Institutes Getting Starting.TM The Carbon Footprint 8 The Constellation Experience A Broad Inventory 1. Scope I-Direct Emissions works.TM The Carbon Footprint 10 The Constellation Experience A Broad Inventory 3. Scope III

Fath, Brian D.

99

Carbon Nanotube Image Gallery  

NSDL National Science Digital Library

The mission of NanoLab, Inc. is to utilize nanoscale science and engineering to create high value products from carbon nanotubes, aligned carbon nanotube arrays, and other nanomaterials. This website provides an image gallery of: carbon nanotubes, nanoparticles, nanowire, as well as nanotube fillings, coatings, and arrays.

100

Carbon Goes To…  

ERIC Educational Resources Information Center

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…

Savasci, Funda

2014-01-01

101

Nonmagnetic carbon nanotubes  

Microsoft Academic Search

We have synthesized by chemical vapor deposition (CVD) single-, double-, and multiwalled carbon nanotubes without magnetic impurities. In particular, we have applied a rhenium-based CVD technique yielding nonmagnetic carbon nanotubes with diamagnetic Re particles. In addition, carbon nanotubes prepared with iron as catalyst particles are annealed at very high temperatures in which the catalyst material is completely vaporized, while the

Kamil Lipert; Florian Kretzschmar; Manfred Ritschel; Albrecht Leonhardt; Rüdiger Klingeler; Bernd Büchner

2009-01-01

102

Molten Carbonate Fuel Cell  

NSDL National Science Digital Library

This page is an introduction to the Molten Carbonate fuel cell. It uses flash animation to explain in greater detail what the Molten Carbonate fuel cell consists of and how it works. The website has an introductory animation which is followed by more in depth description of the molten carbonate fuel cell works.

103

Carbon management and biodiversity  

Microsoft Academic Search

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

Michael A. Huston; Gregg Marland

2003-01-01

104

The Carbon Cycle  

NSDL National Science Digital Library

This module covers the basics of the carbon cycle and research efforts that aim to integrate ecology and the earth sciences, and describes new methodologies being developed to explore the carbon cycle. The module is divided into the following sections: Overview, Exchanges between Reservoirs, Feedbacks in the Carbon Cycle, Implications for Global Climate, Questions and Discussion Topics, Glossary, and Suggested Reading.

Elizabeth Sulzman

105

Intro to Carbon Sequestration  

ScienceCinema

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.

None

2010-01-08

106

Intro to Carbon Sequestration  

SciTech Connect

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.

2008-03-06

107

Protolytic carbon film technology  

SciTech Connect

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.

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

1996-04-01

108

Carbon offsetting: sustaining consumption?  

Microsoft Academic Search

In this paper we examine how theories of sustainable and ethical consumption help us to understand a new, rapidly expanding type of consumer product designed to mitigate climate change: carbon offsets. The voluntary carbon offset market grew by 200% between 2005 and 2006, and there are now over 150 retailers of voluntary carbon offsets worldwide. Our analysis concentrates on the

Heather Lovell; Harriet Bulkeley; Diana Liverman

2009-01-01

109

Screen for Carbon Dioxide.  

ERIC Educational Resources Information Center

Presents a set of laboratory experiments that can assist students in the detection of carbon dioxide. Offers a variation of the supported drop method of carbon dioxide detection that provides readily visible positive results. Includes background information on carbon dioxide. (ML)

Foster, John; And Others

1986-01-01

110

Carbon in detonations  

SciTech Connect

We review three principal results from a five year study of carbon and its properties in detonations and discuss the implications of these results to the behavior of explosives. We first present a new determination of the carbon melt line from release wave velocity measurements in the shocked state. We then outline a colloidal theory of carbon clustering which from diffusion limited coagulation predicts a slow energy release rate for the carbon chemistry. Finally, we show the results from the examination of recovered soot. Here we see support for the colloid theory and find the diamond phase of carbon. The main theme of this paper is that the carbon in detonation products is in the form of a colloidal suspension of carbon clusters which grow through diffusion limited collisions. Even the final state is not bulk graphite or diamond, but is a collection of small, less than 100 /angstrom/A, diamond and graphitic clusters. 23 refs., 4 figs.

Johnson, J.D.

1989-01-01

111

Carbon dioxide sequestration by direct mineral carbonation with carbonic acid  

SciTech Connect

The Albany Research Center (ARC) of the US Department of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. The ARC tests have focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite and member (mg{sub 2}SiO{sub 4})], or serpentine [Mg{sub 3}Si{sub 2}O{sub 5}(OH){sub 4}]. This slurry is reacted with supercritical carbon dioxide (CO{sub 2}) to produce magnesite (MgCO{sub 3}). The CO{sub 2} is dissolved in water to form carbonic acid (H{sub 2}CO{sub 3}), which dissociates to H{sup +} and HCO{sub 3}{sup {minus}}. The H{sup +} reacts with the mineral, liberating Mg{sup 2+} cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and for this reason, these results may also be applicable to in-situ geological sequestration regimes. Results of the baseline tests, conducted on ground products of the natural minerals, have been encouraging. Tests conducted at ambient temperature (22 C) and subcritical CO{sub 2} pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times. Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185 C and a partial pressure of CO{sub 2} (P{sub CO{sub 2}}) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction conditions, have achieved roughly 83% conversion of heat treated serpentine and 84% conversion of olivine to the carbonate in 6 hours. The results from the current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, or some combination of the two. Future tests are intended to examine a broader pressure/temperature regime, various pretreatment options, as well as other mineral groups.

O'Connor, W.K.; Dahlin, D.C.; Nilsen, D.N.; Walters, R.P.; Turner, P.C.

2000-07-01

112

Carbon dioxide sequestration by direct mineral carbonation with carbonic acid  

SciTech Connect

The Albany Research Center (ARC) of the U.S. Dept. of Energy (DOE) has been conducting a series of mineral carbonation tests at its Albany, Oregon, facility over the past 2 years as part of a Mineral Carbonation Study Program within the DOE. Other participants in this Program include the Los Alamos National Laboratory, Arizona State University, Science Applications International Corporation, and the DOE National Energy Technology Laboratory. The ARC tests have focused on ex-situ mineral carbonation in an aqueous system. The process developed at ARC utilizes a slurry of water mixed with a magnesium silicate mineral, olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. This slurry is reacted with supercritical carbon dioxide (CO2) to produce magnesite (MgCO3). The CO2 is dissolved in water to form carbonic acid (H2CO3), which dissociates to H+ and HCO3 -. The H+ reacts with the mineral, liberating Mg2+ cations which react with the bicarbonate to form the solid carbonate. The process is designed to simulate the natural serpentinization reaction of ultramafic minerals, and for this reason, these results may also be applicable to in-situ geological sequestration regimes. Results of the baseline tests, conducted on ground products of the natural minerals, have been encouraging. Tests conducted at ambient temperature (22 C) and subcritical CO2 pressures (below 73 atm) resulted in very slow conversion to the carbonate. However, when elevated temperatures and pressures are utilized, coupled with continuous stirring of the slurry and gas dispersion within the water column, significant reaction occurs within much shorter reaction times. Extent of reaction, as measured by the stoichiometric conversion of the silicate mineral (olivine) to the carbonate, is roughly 90% within 24 hours, using distilled water, and a reaction temperature of 185?C and a partial pressure of CO2 (PCO2) of 115 atm. Recent tests using a bicarbonate solution, under identical reaction conditions, have achieved roughly 83% conversion of heat treated serpentine and 84% conversion of olivine to the carbonate in 6 hours. The results from the current studies suggest that reaction kinetics can be improved by pretreatment of the mineral, catalysis of the reaction, or some combination of the two. Future tests are intended to examine a broader pressure/temperature regime, various pretreatment options, as well as other mineral groups.

O'Connor, William K.; Dahlin, David C.; Nilsen, David N.; Walters, Richard P.; Turner, Paul C.

2000-01-01

113

Process of making carbon-carbon composites  

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

114

Enhanced carbon dioxide adsorption through carbon nanoscrolls.  

PubMed

Over the last few years, significant efforts have been devoted to exploring the capabilities of carbon based structures for gas separation and filtration. In the present study the layering behavior of carbon dioxide transported through carbon nanoscrolls is examined through molecular dynamics simulations. The layering arrangements are investigated for carbon nanoscrolls with intralayer distances spanning from 4.2 to 8.3 Å at temperature of 300 K and pressures ranging from 5 to 20 bars. Characteristic layering structures are developed around the internal and external surfaces of the nanoscroll for all the examined cases. It is shown that the number of layers, their relative strength, and the starting point of bifurcation phenomena vary as a function of the nanoscrolls' intralayer distance, scroll's core radius, CO2 density, and gas structure interactions. It is also shown that the number of carbon dioxide molecules adsorbed per scroll's carbon particles is a function of the scroll's surface-to-volume ratio and is maximized under certain structural configurations. PMID:22304187

Mantzalis, Dimitrios; Asproulis, Nikolaos; Drikakis, Dimitris

2011-12-01

115

Mechanical behavior of carbon-carbon composites  

NASA Technical Reports Server (NTRS)

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.

Rozak, G. A.

1984-01-01

116

Carbon isotopes in mollusk shell carbonates  

NASA Astrophysics Data System (ADS)

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 ?13C reflects the local mix of C3 and C4 plants consumed. Shell ?13C 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 ?13C is typically a few ‰ lower than ambient DIC, and often decreases with age. Shell ?13C 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.

McConnaughey, Ted A.; Gillikin, David Paul

2008-10-01

117

Carbon dioxide sensor  

SciTech Connect

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).

Dutta, Prabir K. (Worthington, OH); Lee, Inhee (Columbus, OH); Akbar, Sheikh A. (Hilliard, OH)

2011-11-15

118

COPPER-CATALYZED CROSS-COUPLING REACTIONS: THE FORMATION OF CARBON-CARBON AND CARBON-SULFUR BONDS  

E-print Network

COPPER-CATALYZED CROSS-COUPLING REACTIONS: THE FORMATION OF CARBON-CARBON AND CARBON-SULFUR BONDS-COUPLING REACTIONS: THE FORMATION OF CARBON-CARBON AND CARBON-SULFUR BONDS A Dissertation Presented by CRAIG G. BATES: THE FORMATION OF CARBON-CARBON AND CARBON-SULFUR BONDS MAY 2005 CRAIG G BATES, B.S., ROGER WILLIAMS UNIVERISTY

Venkataraman, Dhandapani "DV"

119

Preparation of synthetic carbon adsorbents by polyvinyl chloride (PVC) carbonization  

Microsoft Academic Search

Preparation of synthetic carbon adsorbents by carbonization of polyvinyl chloride (produced by Anwil, Wocawek, Poland) is described in the paper. The influence of polyvinyl chloride (PVC) carbonization conditions on the porous structure of the obtained carbon was studied. Part of the prepared carbonizates was activated in the atmosphere of in water vapour and carbon dioxide (600 - 800 oC). The

SECTIO AA; M. Seredych; A. Gierak

120

Carbon RRLs Carbon RRLs towards Ultra-compact HII Regions  

E-print Network

Carbon RRLs Carbon RRLs towards Ultra-compact HII Regions Dana S. Balser D. Anish Roshi (Raman (Agnes Scott College) #12;Carbon RRLs Carbon Radio Recombination Lines (RRLs) NGC 2024 (Orion B) IC 1795 (W3) Palmer et al. (1967) #12;Carbon RRLs Photodissociation Regions (PDRs) Hollenbach & Tielens (1997

Balser, Dana S.

121

Pyrolytic carbon electrodes Lithographically Defined Porous Carbon Electrodes**  

E-print Network

Pyrolytic carbon electrodes Lithographically Defined Porous Carbon Electrodes** D. Bruce Burckel Polsky* The special nature of the CÃ?C bond can lead to various polymorphic forms of carbon such as graphite, glassy-carbon, fullerenes (such as buckyballs), carbon nanotubes, and diamond. Electrodes made

New Mexico, University of

122

Carbon nanofibers and carbon nanotubes in regenerative medicine  

Microsoft Academic Search

Carbon nanotubes and carbon nanofibers have long been investigated for applications in composite structural materials, semiconductor devices, and sensors. With the recent well-documented ability to chemically modify nanofibrous carbon materials to improve their solubility and biocompatibility properties: a whole new class of bioactive carbon nanostructures has been created for biological applications. This review focuses on the latest applications of carbon

Phong A. Tran; Lijie Zhang; Thomas J. Webster

2009-01-01

123

Creating With Carbon  

NASA Technical Reports Server (NTRS)

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.

2003-01-01

124

Mesoporous carbon materials  

DOEpatents

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.

Dai, Sheng (Knoxville, TN); Wang, Xiqing (Oak Ridge, TN)

2012-02-14

125

Mesoporous carbon materials  

DOEpatents

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.

Dai, Sheng; Wang, Xiqing

2013-08-20

126

Molten carbonate fuel cell separator  

DOEpatents

In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

Nickols, R.C.

1984-10-17

127

Molten carbonate fuel cell separator  

DOEpatents

In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

Nickols, Richard C. (East Hartford, CT)

1986-09-02

128

The carbon dioxide cycle  

USGS Publications Warehouse

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.

James, P.B.; Hansen, G.B.; Titus, T.N.

2005-01-01

129

Sodium reactivity with carbons  

Microsoft Academic Search

We report in this paper some results on the reactivity of different carbon materials, and in particular a set of pitch-coke samples heat treated between 800 and 2400 °C, with sodium. An experimental cell has been designed, which allows carbon to react with sodium vapor at relative pressure close to 0.9 up to 800 °C. The different carbon-sodium samples were

L. Joncourt; M. Mermoux; P. H. Touzain; L. Bonnetain; D. Dumas; B. Allard

1996-01-01

130

USGS Carbon Cycle Research  

NSDL National Science Digital Library

This portal provides access to information on United States Geological Survey (USGS) research activities conducted in support of the U.S. Carbon Cycle Science Program (CCSP). This research includes carbon sequestration in sediments, landscape dynamics and vegetation change, fate of carbon in cold region forests, exchanges of greenhouse gases, water vapor, and heat at the Earth's surface, and other topics. Each topic heading features links to reports or program webpages.

131

The Carbon Cycle  

NSDL National Science Digital Library

Since living things extract carbon from their nonliving environment, for life to continue carbon must be recycled. This site tells us that the cycle is not in balance and explores the possibilities of where the missing carbon might be found. The site also explains the greenhouse effect and global warming and also covers the other greenhouse gases such as methane and chlorofluorocarbons (CFCs). It also features diagrams, a graph, and links to other sites for more detailed information.

John Kimball

132

Seeing the Carbon Cycle  

NSDL National Science Digital Library

The most important biochemical reactions for life in the ocean and on Earth are cellular respiration and photosynthesis. These two reactions play a central role in the carbon cycle. The ocean-based carbon cycle is highly relevant to today's students because of its key role in global warming. This experiment allows middle school students to observe the influence of the carbon cycle on algae growth, explore experimental design, collect data, and draw a conclusion.

Catherine Cramer

2006-01-01

133

Why is Carbon Important?  

NSDL National Science Digital Library

Students explore the carbon cycle and the relationship between atmospheric carbon dioxide concentrations and temperature. Students create and compare graphs of carbon dioxide and temperature data from one local (Mauna Loa, Hawaii) meteorological station and one NASA global data set. These graphs, as well as a global vegetation map and an atmospheric wind circulation patterns diagram, are used as evidence to support the scientific claims they develop through their analysis and interpretation.

NASA Goddard Space Flight Center

134

Temperature VS Carbon Dioxide  

NSDL National Science Digital Library

In this activity, students examine the relationship between carbon dioxide levels and global temperature change by studying a graph of these two variables. They will discover that by using data from ice cores, scientists can determine temperature and carbon dioxide levels in the air as far back as a hundred thousand years in the past. The students try to predict which variable is the independent one and then make a graph of temperature change and carbon dioxide levels. After making their graph, students describe the relationship between temperature and carbon dioxide levels in the atmosphere to determine if their predictions were correct.

135

Carbon Monoxide Toxicity  

PubMed Central

Of all fatal poisonings in the United States, an estimated half are due to carbon monoxide. The number of non-lethal poisonings due to carbon monoxide is difficult to estimate because signs and symptoms of carbon monoxide poisoning cover a wide spectrum and mimic other disorders. Misdiagnosis is serious, as the patient often returns to the contaminated environment. Those not receiving proper treatment are at significant risk, as high as 10% to 12%, of developing late neurological sequelae. The diagnosis of carbon monoxide poisoning depends upon precise history taking, careful physical examination, and a high index of suspicion. ImagesFigure 2 PMID:21221282

Aniol, Michael J.

1992-01-01

136

Calcium carbonate overdose  

MedlinePLUS

Tums overdose; Calcium overdose ... Calcium ... Products containing calcium carbonate, including Certain antacids (Tums, Chooz) Certain mineral supplements Certain hand lotions Certain vitamin and mineral supplements Note: ...

137

Nanographene reinforced carbon/carbon composites  

NASA Astrophysics Data System (ADS)

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 dispersions compared to VGCNF/phenolic dispersions. In nanocomposites, at low concentration (? 1.5 wt%), NGP were effective in increasing the flexure strength, char content and lowering the porosity and coefficient of thermal expansion of neat phenolic resin. At higher concentration (>1.5wt%), NGP had a tendency to agglomerate and lost their effectiveness. The behavior observed in nanocomposites continued in manufactured CCC. The highest Inter Laminar Shear Strength (ILSS), flexure strength/modulus, stiffness and density was observed at 1.5 wt% NGP. In CCC at concentrations > 1.5 wt%, the properties (ILSS, flexure, stiffness, density) decreased due to agglomeration but they were still higher compared to that of neat CCC (without NGP).

Bansal, Dhruv

138

Carbon dioxide sequestration by mineral carbonation  

SciTech Connect

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.

Gerdemann, Stephen J.; Dahlin David C.; O'Connor William K.; Penner Larry R.

2003-11-01

139

Method for Making a Carbon-Carbon Cylinder Block  

NASA Technical Reports Server (NTRS)

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.

Ransone, Phillip O. (Inventor)

1997-01-01

140

Low Cost Carbon Fiber Production Carbon Fiber Manufacturing Cost Modeling  

E-print Network

Low Cost Carbon Fiber Production Carbon Fiber Manufacturing Cost Modeling Oak Ridge National spinning, and the low mass conversion yield of precursor to carbon fiber. Alternative precursors have22725 Research Areas Freight Flows Passenger Flows Supply Chain Efficiency Transportation: Energy

141

Microbially mediated mineral carbonation  

NASA Astrophysics Data System (ADS)

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 implemented and economically efficient alternative to other technologies currently under development for mineral sequestration. Dismukes GC, Carrieri D, Bennette N, Ananyev GM, Posewitz MC (2008) Aquatic phototrophs: efficient alternatives to land-based crops for biofuels. Current Opinion in Biotechnology, 19, 235-240. Ferris FG, Wiese RG, Fyfe WS (1994) Precipitation of carbonate minerals by microorganisms: Implications of silicate weathering and the global carbon dioxide budget. Geomicrobiology Journal, 12, 1-13. Lackner KS, Wendt CH, Butt DP, Joyce EL, Jr., Sharp DH (1995) Carbon dioxide disposal in carbonate minerals. Energy, 20, 1153-1170. Power IM, Wilson SA, Thom JM, Dipple GM, Gabites JE, Southam G (2009) The hydromagnesite playas of Atlin, British Columbia, Canada: A biogeochemical model for CO2 sequestration. Chemical Geology, 206, 302-316. Thompson JB, Ferris FG (1990) Cyanobacterial precipitation of gypsum, calcite, and magnesite from natural alkaline lake water. Geology, 18, 995-998.

Power, I. M.; Wilson, S. A.; Dipple, G. M.; Southam, G.

2010-12-01

142

Mantle carbon flux calculated  

NASA Astrophysics Data System (ADS)

A geochemist at the National Aeronautics and Space Administration (NASA) Ames Research Center (Moffett Field, Calif.) has greatly improved the accuracy of determining oceanic carbon outgassing rates by developing a new technique for extracting carbon dioxide that prevents contamination. David Des Marias burned his rock samples in pure oxygen at 450°C and then 650°C, before melting them at 1200°C to expel the gases. The samples remained in the same apparatus throughout the cleaning and melting, allowing Des Marais to clean the sample while limiting atmospheric contamination. His earlier work with lunar samples had shown that the process was effective, since only minor amounts of carbon were found in those samples after the cleaning.By analyzing samples of glassy ocean ridge tholeiites from the Mid-Cayman Rise, the East Pacific Rise (21°N), the Mid-Atlantic Ridge, and the Galapagos Ridge, Des Marais determined the ratio of carbon to 3He in the samples. Then, by relating that ratio to an established rate for total oceanic 3He flux, he calculated a mantle carbon flux of 20-30 million tons of carbon per year. The carbon emitted from the ocean ridges and other undersea volcanic areas represents more than 90% of the global carbon outflow from the mantle. Two other previous estimates of carbon outflow ranged from 0.1 to 10 times his result. Des Marais' finding is considered the most accurate because he was able to accurately measure carbon and 3He without depending on the assumptions made by others that all CO2 comes from volcanos and all the carbon emitted from the mantle has been preserved at the surface.

Wainger, Lisa

1988-03-01

143

Elevated atmospheric carbon dioxide increases soil carbon  

SciTech Connect

In a study funded by the U.S. Department of Energy's Office of Science, researchers from Argonne and Oak Ridge National Laboratories and Kansas State and Texas A&M Universities evaluated the collective results of earlier studies by using a statistical procedure called meta-analysis. They found that on average elevated CO2 increased soil carbon by 5.6 percent over a two to nine year period. They also measured comparable increases in soil carbon for Tennessee deciduous forest and Kansas grassland after five to eight years of experimental exposure to elevated CO2.

Norby, Richard J [ORNL; Jastrow, Julie D [ORNL; Miller, Michael R [ORNL; Matamala, Roser [Argonne National Laboratory (ANL); Boutton, Thomas W [Texas A& M University; Rice, Charles W [ORNL; Owensby, Clenton E [Kansas State University

2005-01-01

144

Carbon Energy Flows Belowground  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plants use photosynthesis to convert carbon dioxide in the atmosphere and energy from sunlight into energy-containing, carbon-based foodstuffs (i.e. carbohydrates such as sugars and starches) that provide the building blocks for all life on Earth. Without photosynthesis, sunlight would not be a goo...

145

The carbon cycle revisited  

NASA Technical Reports Server (NTRS)

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.

Bolin, Bert; Fung, Inez

1992-01-01

146

Modeling Carbon Exchange  

NASA Technical Reports Server (NTRS)

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.

Sellers, Piers

2012-01-01

147

Seeing the Carbon Cycle  

ERIC Educational Resources Information Center

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,…

Drouin, Pamela; Welty, David J.; Repeta, Daniel; Engle-Belknap, Cheryl A.; Cramer, Catherine; Frashure, Kim; Chen, Robert

2006-01-01

148

Magnetoconductance of carbon nanotubes  

Microsoft Academic Search

As a result of the interaction between the spin and the magnetic field (B), special step structures are predicted to exist in the ballistic magnetoconductance of carbon nanotubes. The electronic structure of a carbon nanotube drastically changes from a metal (semiconductor) to a semiconductor (metal) during the variation of the magnetic flux. When the spin-B interaction is neglected, the Fermi

M. F. Lin; Kenneth W.-K. Shung

1995-01-01

149

Ingredients for Life: Carbon  

NSDL National Science Digital Library

Carbon is the basis of all organic molecules. It is also one of the most abundant elements in the universe. This video segment illustrates the special characteristics of carbon that make it an essential ingredient for life. The segment is one minute thirty-eight seconds in length. A background essay and list of discussion questions are also provided.

150

Material Science of Carbon  

Microsoft Academic Search

Carbon is a ubiquitous material that is essential for the functioning of modern society. Because carbon can exist in a multitude of forms, it can be tailored to possess practically any property that might be required for a specific application. The list of applications is very extensive and includes: aircraft brakes, electrodes, high temperature molds, rocket nozzles and exit cones,

Wesley P. Hoffman

2005-01-01

151

Lead carbonate scintillator materials  

DOEpatents

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.

Derenzo, Stephen E. (Pinole, CA); Moses, William W. (Berkeley, CA)

1991-01-01

152

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 ...

153

Sustainable carbon materials.  

PubMed

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. PMID:25301517

Titirici, Maria-Magdalena; White, Robin J; Brun, Nicolas; Budarin, Vitaliy L; Su, Dang Sheng; del Monte, Francisco; Clark, James H; MacLachlan, Mark J

2015-01-01

154

Carbon films from polyacrylonitrile  

Microsoft Academic Search

Polyacrylonitrile (PAN) films have been fabricated by both spin and solvent casting techniques, and pyrolyzed to produce carbon films in the thickness range of 200--50 000 A. These films have higher electrical conductivities than carbon films produced from most other precursors at similar temperatures. The chemical structure of the films at different stages of processing was investigated by UV, IR,

C. L. Renschler; A. P. Sylwester; L. V. Salgado

1989-01-01

155

Ingredients for Life: Carbon  

NSDL National Science Digital Library

Carbon is the basis of all organic molecules. It is also one of the most abundant elements in the universe. This video segment illustrates the special characteristics of carbon that make it an essential ingredient for life. The segment is one minute thirty-eight seconds in length. A background essay and list of discussion questions are also provided.

2011-07-22

156

Carbon capture and storage  

Microsoft Academic Search

Carbon capture and storage (CCS) covers a broad range of technologies that are being developed to allow carbon dioxide (CO2) emissions from fossil fuel use at large point sources to be transported to safe geological storage, rather than being emitted to the atmosphere. Some key enabling contributions from technology development that could help to facilitate the widespread commercial deployment of

Jon Gibbins; Hannah Chalmers

2008-01-01

157

Amorphous-Carbon Films  

NASA Technical Reports Server (NTRS)

Report describes structure, preparation, characterization, and applications of films of amorphous-carbon. Amorphous-carbon films potentially useful as masks in x-ray lithography, layers for passivation of high-speed microelectronic circuits, hard films to protect magnetic recording media and optical components from degradation by chemical etching or wear, and radiation detectors.

Pouch, John J.; Alterovitz, Samuel A.

1993-01-01

158

Carbon Dioxide Fountain  

ERIC Educational Resources Information Center

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.)…

Kang, Seong-Joo; Ryu, Eun-Hee

2007-01-01

159

Carbon Dioxide Emission Estimates  

NSDL National Science Digital Library

The Carbon Dioxide Information Analysis Center of the Oak Ridge National Laboratory provides this new data on carbon dioxide emissions from fossil fuel burning, hydraulic cement production, and gas flaring in 1995. Data for one degree grid cells can be downloaded from the site in addition to code for analysis of the data.

160

Carbon nanotubes for nanorobotics  

Microsoft Academic Search

The well-defined geometry, exceptional mechanical properties, and extraordinary electrical characteristics of carbon nanotubes qualify them for structuring nanoelectronic circuits, nanoelectromechanical systems, and nanorobotic systems. Relative displacements between the atomically smooth, nested shells in multiwalled carbon nanotubes can be used as robust nanoscale motion enabling mechanisms for applications such as bearings, switches, gigahertz oscillators, shuttles, memories, syringes, and actuators. The hollow

Lixin Dong; Arunkumar Subramanian; Bradley J. Nelson

2007-01-01

161

Fly ash carbon passivation  

DOEpatents

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.

La Count, Robert B; Baltrus, John P; Kern, Douglas G

2013-05-14

162

Production of Carbon Dioxide  

NSDL National Science Digital Library

In this chemistry activity, learners use common chemicals to produce carbon dioxide and observe its properties. This resource includes brief questions for learners to answer after the experiment. Use this activity to introduce learners to carbon dioxide and its use as a fire extinguisher. Note: this activity involves an open flame.

The Science House

2014-01-28

163

Simplified Carbonate Sequence Stratigraphy  

NSDL National Science Digital Library

Students interpret shallow to deep marine carbonate environments developed across a 150-km wide carbonate platform, identify a single depositional sequence (and internal systems tracts), correlate facies, then reconstruct the platform geometry at specific time intervals during sequence development. This exercise is based on a real-world example and can be modified based on available samples.

maya elrick

164

The boundless carbon cycle  

Microsoft Academic Search

4 , they are assumed to lie within the terrestrial biosphere. We argue that inland waters have a significant role in the sequestration, transport and mineralization of organic carbon. Integration of these fluxes into the traditional carbon cycle is needed for appropriate CO2 management and climate change mitigation. Inland waters — such as ponds, lakes, wetlands, streams, rivers and reservoirs

Sebastiaan Luyssaert; Louis A. Kaplan; Anthony K. Aufdenkampe; Andreas Richter; Lars J. Tranvik; Tom J. Battin

2009-01-01

165

Carbon Park Environmental Impact Assessment  

E-print Network

of offsetting the University's carbon footprint, promoting biodiversity and establishing easily maintained Carbon Park Environmental Impact Assessment A B.E.S.T. Project By, Adam Bond 2011 #12; Bishop's University Carbon Park

166

Isolation of Carbon Nanostructures  

SciTech Connect

Carbon nanostructures such a single wall carbon nanotubes (SWCNT), double wall carbon nanotubes (DWCNT) and fullerene peapods (e.g. C70 at SWCNT) usually occur in the form of bundles. Here, we present application of a novel simple and versatile method for deposition of small isolated nanoribbons of carbon nanotubes on annealed gold surface. The nanoribbons were characterized by Raman spectroscopy and exhibit characteristic features of individual carbon nanostructures. The resonance condition allowed the observation of a distinct spectrum of one inner tube in the nanoribbon from DWCNT. The signal of inner tubes of isolated DWCNT nanoribbons was found to be up to 50 times stronger than the sum of signals of the corresponding tubes in buckypaper sample. This dramatic enhancement is assigned to SERS (surface enhanced resonant Raman scattering) effect.

Kalbac, Martin; Kavan, Ladislav [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-182 23 Prague 8 (Czech Republic); Leibniz Institute of Solid State and Materials Research, Helmholtzstr. 20, D - 01069 Dresden (Germany); Pelouchova, Hana; Janda, Pavel; Zukalova, Marketa [J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-182 23 Prague 8 (Czech Republic); Dunsch, Lothar [Leibniz Institute of Solid State and Materials Research, Helmholtzstr. 20, D - 01069 Dresden (Germany)

2005-09-27

167

Hydrogen storage by carbon sorption  

Microsoft Academic Search

This research determined experimentally the extent to which carbon sorbents such as activated carbon, carbon black, carbon aerogels, and carbon molecular sieves can augment the capacity of compressed hydrogen gas (CHG) storage systems. These carbon sorbents were tested at ambient temperature (300 K), at acetone-and-dry-ice temperature (190 K), and at liquid-nitrogen temperature (80 K). We concluded that, at the pressures

Scott Hynek; Ware Fuller; Jeffrey Bentley

1997-01-01

168

Atmospheric Carbon Dioxide and Carbon Reservoir Changes  

Microsoft Academic Search

The net release of CO2 from the biosphere to the atmosphere between 1850 and 1950 is estimated to amount to 1.2 × 109 tons of carbon per year. During this interval, changes in land use reduced the total terrestrial biomass by 7 percent. There has been a smaller reduction in biomass over the last few decades. In the middle 19th

Minze Stuiver

1978-01-01

169

Carbon observation: the Integrated Carbon Observing System  

NASA Astrophysics Data System (ADS)

A better knowledge of the carbon sinks' underlying processes, and their sustainability, is required to assess current mitigation efforts and to better predict the future ability of the carbon cycle to uptake anthropogenic emissions. To address these needs, carbon observations are required to better estimate the fluxes of carbon greenhouse gases to and from the atmosphere. ICOS is a recently-launched, world-class research infrastructure dedicated to the monitoring and improved understanding of carbon sources and sinks. It consists of complementary, harmonized networks of long-term ecosystem monitoring stations focusing on Europe and adjacent regions. The ICOS networks will comprise 40 operational atmospheric stations (measuring atmospheric composition in greenhouse gases and other core parameters), as many ecosystem stations (measuring fluxes from ecosystems) and about 10 oceanic measurement platforms. The operational status is expected in 2014. The networks will be coordinated through a set of central facilities: three Thematic centres respectively for atmospheric, ecosystem and ocean data and stations performance assessment, and a Central analytical lab. The mission of the thematic centres is to process, validate and distribute data to end-users. ICOS will also set up a Carbon portal dedicated to easy discovery of and access to data and elaborated products such as flux maps by end users. Through its European Commission funded Preparatory phase ICOS has demonstrated its capability to monitor greenhouse gases across Europe at 4 atmospheric sites and 4 ecosystem sites, working in near real time with the Atmospheric and Ecosystem Thematic Centres. At this occasion, the instrumental package, the experimental set up and protocols prepared for the standardized ICOS station are tested. ICOS measurements will allow the estimation of regional fluxes at a typical resolution of 50 km daily from the atmospheric network, with a precision of ~40 gC m-2 yr-1. The ecosystem network informs on the small scale variability of fluxes and its drivers. ICOS needs to be well connected and interoperable with other global and regional networks. When completed, ICOS will contribute to provide the essential long-term observations required to understand the present state and predict future behaviour of the global carbon cycle and greenhouse gases' emissions.

Paris, J.; Ciais, P.; Papale, D.; Rivier, L.; Consortium, I.

2012-12-01

170

Prokaryotic carbonic anhydrases.  

PubMed

Carbonic anhydrases catalyze the reversible hydration of CO(2) [CO(2)+H(2)Oright harpoon over left harpoon HCO(3)(-)+H(+)]. Since the discovery of this zinc (Zn) metalloenzyme in erythrocytes over 65 years ago, carbonic anhydrase has not only been found in virtually all mammalian tissues but is also abundant in plants and green unicellular algae. The enzyme is important to many eukaryotic physiological processes such as respiration, CO(2) transport and photosynthesis. Although ubiquitous in highly evolved organisms from the Eukarya domain, the enzyme has received scant attention in prokaryotes from the Bacteria and Archaea domains and has been purified from only five species since it was first identified in Neisseria sicca in 1963. Recent work has shown that carbonic anhydrase is widespread in metabolically diverse species from both the Archaea and Bacteria domains indicating that the enzyme has a more extensive and fundamental role in prokaryotic biology than previously recognized. A remarkable feature of carbonic anhydrase is the existence of three distinct classes (designated alpha, beta and gamma) that have no significant sequence identity and were invented independently. Thus, the carbonic anhydrase classes are excellent examples of convergent evolution of catalytic function. Genes encoding enzymes from all three classes have been identified in the prokaryotes with the beta and gamma classes predominating. All of the mammalian isozymes (including the 10 human isozymes) belong to the alpha class; however, only nine alpha class carbonic anhydrase genes have thus far been found in the Bacteria domain and none in the Archaea domain. The beta class is comprised of enzymes from the chloroplasts of both monocotyledonous and dicotyledonous plants as well as enzymes from phylogenetically diverse species from the Archaea and Bacteria domains. The only gamma class carbonic anhydrase that has thus far been isolated and characterized is from the methanoarchaeon Methanosarcina thermophila. Interestingly, many prokaryotes contain carbonic anhydrase genes from more than one class; some even contain genes from all three known classes. In addition, some prokaryotes contain multiple genes encoding carbonic anhydrases from the same class. The presence of multiple carbonic anhydrase genes within a species underscores the importance of this enzyme in prokaryotic physiology; however, the role(s) of this enzyme is still largely unknown. Even though most of the information known about the function(s) of carbonic anhydrase primarily relates to its role in cyanobacterial CO(2) fixation, the prokaryotic enzyme has also been shown to function in cyanate degradation and the survival of intracellular pathogens within their host. Investigations into prokaryotic carbonic anhydrase have already led to the identification of a new class (gamma) and future research will undoubtedly reveal novel functions for carbonic anhydrase in prokaryotes. PMID:10978542

Smith, K S; Ferry, J G

2000-10-01

171

Carbon dioxide adsorbent study  

NASA Technical Reports Server (NTRS)

A study was initiated on the feasibility of using the alkali metal carbonate - bi-carbonate solid-gas reaction to remove carbon dioxide from the atmosphere of an EVA life support system. The program successfully demonstrates that carbon dioxide concentrations could be maintained below 0.1 mole per cent using this chemistry. Further a practical method for distributing the carbonates in a coherent sheet form capable of repeated regeneration (50 cycles) at modest temperatures (423 K), without loss in activity was also demonstrated. Sufficiently high reaction rates were shown to be possible with the carbonate - bi-carbonate system such that EVA hardware could be readily designed. Experimental and design data were presented on the basis of which two practical units were designed. In addition to conventional thermally regenerative systems very compact units using ambient temperature cyclic vacuum regeneration may also be feasible. For a one man - 8 hour EVA unit regenerated thermally at the base ship a system volume of 14 liters is estimated.

Onischak, M.; Baker, B. S.

1973-01-01

172

Carbon monoxide poisoning (acute)  

PubMed Central

Introduction Carbon monoxide is an odourless, colourless gas, and poisoning causes hypoxia, cell damage, and death. Exposure to carbon monoxide is measured either directly from blood samples and expressed as a percentage of carboxyhaemoglobin, or indirectly using the carbon monoxide in expired breath. Carboxyhaemoglobin percentage is the most frequently used biomarker of carbon monoxide exposure. Although the diagnosis of carbon monoxide poisoning can be confirmed by detecting elevated levels of carboxyhaemoglobin in the blood, the presence of clinical signs and symptoms after known exposure to carbon monoxide should not be ignored. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of oxygen treatments for acute carbon monoxide poisoning? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2007 (BMJ Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 12 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: 100% hyperbaric oxygen, oxygen 28%, and oxygen 100% by non-re-breather mask. PMID:19445736

2008-01-01

173

Carbon monoxide poisoning (acute)  

PubMed Central

Introduction Carbon monoxide is an odourless, colourless gas, and poisoning causes hypoxia, cell damage, and death. Exposure to carbon monoxide is measured either directly from blood samples and expressed as a percentage of carboxyhaemoglobin, or indirectly using the carbon monoxide in expired breath. Carboxyhaemoglobin percentage is the most frequently used biomarker of carbon monoxide exposure. Although the diagnosis of carbon monoxide poisoning can be confirmed by detecting elevated levels of carboxyhaemoglobin in the blood, the presence of clinical signs and symptoms after known exposure to carbon monoxide should not be ignored. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of oxygen treatments for acute carbon monoxide poisoning? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 12 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: 100% hyperbaric oxygen, oxygen 28%, and oxygen 100% by non-re-breather mask. PMID:21418677

2010-01-01

174

The Growth and Characterization of Germanium-Carbon Alloy Thin Films and Solid Phase Equilibria for Metal-Silicon - Ternary Systems: Magnesium, Calcium, Strontium, Barium, Scandium, Yttrium, Lanthanum, Titanium, Zirconium and Hafnium  

NASA Astrophysics Data System (ADS)

Thin films of pure germanium-carbon alloys (Ge _{rm x}C _{rm 1-x} with 0 <=q x <=q 1) have been grown on Si and Al_2O_3 substrates by pulsed laser ablation in a high vacuum chamber. The films were analyzed by x-ray 0-20 diffraction (XRD), x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), conductivity measurements and optical absorption spectroscopy. The analyses of these new materials showed that films of all compositions were amorphous, free of contamination and uniform in composition. By changing the film composition, the optical band gap of these semiconducting films was varied from 0.00 eV to 0.85 eV for x = 0.0 to 1.0 respectively. According to the AES results, the carbon atoms in the Ge-C alloy thin film samples have a bonding structure that is a mixture of sp^2 and sp^3 hybridizations. The presence of the sp^2 C is apparently what causes the bandgap of amorphous Ge-C alloys to decrease with increasing carbon concentration. The solidus portion of the ternary phase diagrams of the type M-Si-O, where M = Mg, Ca, Sr, Ba, Sc, Y, La, Ti, Zr and Hf have been derived at 298K and 1 atm oxygen partial pressure by investigating the bulk reactions possible in these systems. These phase diagrams, which have been determined by experiments and by calculations using thermodynamic data available, can be used to predict the occurrence of the reaction products or the stability of the phases present at the interfaces between different solid materials. Hence, they provide guides in designing thin film structures and in selecting candidate materials to form chemically stable interfaces. A research effort has been made on the investigation of the growth of diamond thin films from a carbon containing solid-CI_4, using laser ablation technique. The film grown by laser ablation from CI _4 is mainly composed of carbon with very small amount of oxygen and iodine as indicated by x-ray photoelectron spectroscopy data. The Auger electron spectroscopy result shows that the film grown contains a mixture of sp^2 and sp^3 hybridized carbon. By using x-ray powder diffraction and magnetic susceptibility measurements methods, we studied the chemical stability of candidate interlayer materials between YBa _2Cu_3O _7-delta and Si. The results show that CaF_2 reacts with YBCO while BaF_2 is chemically stable with YBCO. LaGaO_3 and Ca _2SiO_4 are chemically stable with Si and more investigations need to be made on the reactivity between Ca_2SiO _4 and YBCO.

Yuan, Haojie

1992-09-01

175

Carbon Sequestration via Mineral Carbonation: Overview and Assessment  

E-print Network

1 Carbon Sequestration via Mineral Carbonation: Overview and Assessment 14 March 2002 Howard Herzog overview and assessment of carbon sequestration by mineral carbonation (referred to as "mineral Coal Alliance) combines a capture process with mineral sequestration. However, this report looks only

176

Pistons and Cylinders Made of Carbon-Carbon Composite Materials  

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

177

Cumulative Carbon and Just Allocation of the Global Carbon Commons  

E-print Network

Cumulative Carbon and Just Allocation of the Global Carbon Commons R.T. Pierrehumbert* Abstract statistic, called cumulative carbon. This statistic is the aggregate amount ofcarbon emitted in theform such activitiespersist.In thispaper the conceptis usedto addressthe question offair allocation of carbon emissions

Pierrehumbert, Raymond

178

SCALE-UP OF CARBON /CARBON BIPOLAR PLATES  

E-print Network

#12;SCALE-UP OF CARBON /CARBON BIPOLAR PLATES Quarterly Report to the Department of Energy, May 19 Scale-up of Carbon/Carbon Bipolar Plates · Project Objectives ­ Build and demonstrate a pilot facility capable of producing 300 bipolar plates per hour ­ Develop a quality assurance plan for the facility

179

Integrating aquatic carbon fluxes in a boreal catchment carbon budget  

Microsoft Academic Search

In this paper, we assess the extent to which the export of terrestrially fixed carbon to aquatic systems and the aquatic metabolism of this carbon affect the overall accumulation of organic carbon in a boreal catchment. We estimated the contribution of stocks and processes in aquatic environments to the carbon balance of a boreal catchment in northern Sweden. We used

A. Jonsson; G. Algesten; A.-K. Bergström; K. Bishop; S. Sobek; L. J. Tranvik; M. Jansson

2007-01-01

180

Pistons and Cylinders Made of Carbon-Carbon Composite Materials  

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

181

A novel carbon fiber based porous carbon monolith  

SciTech Connect

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.

Burchell, T.D.; Klett, J.W.; Weaver, C.E.

1995-07-01

182

Carbon footprint calculator  

NSDL National Science Digital Library

This site is produced by British Petroleum and provides a simple, interactive guide to estimate your annual household carbon emissions. The calculator asks questions about the features of your residence, car travel, air travel and recycling habits. As each question is answered, a graph displays the carbon emissions so you can see the effects of each of the options presented. This tool is intended as an approximate guide only, but is useful for stimulating an awareness of the approximate amount of carbon dioxide emitted by everyday tasks.

British Petroleum

183

Introduction to Carbon Nanotubes  

NASA Astrophysics Data System (ADS)

Carbon nanotubes are among the amazing objects that science sometimes creates by accident, without meaning to, but that will likely revolutionize the technological landscape of the century ahead. Our society stands to be significantly influenced by carbon nanotubes, shaped by nanotube applications in every aspect, just as silicon-based technology still shapes society today. The world already dreams of space-elevators tethered by the strongest of cables, hydrogen-powered vehicles, artificial muscles, and so on - feasts that would be made possible by the emerging carbon nanotube science.

Monthioux, Marc; Serp, Philippe; Flahaut, Emmanuel; Razafinimanana, Manitra; Laurent, Christophe; Peigney, Alain; Bacsa, Wolfgang; Broto, Jean-Marc

184

Carbon Nanotubes in Neuroscience  

PubMed Central

Carbon nanotubes have electrical, mechanical and chemical properties that make them one of the most promising materials for applications in neuroscience. Single-walled and multi-walled carbon nanotubes have been increasingly used as scaffolds for neuronal growth and more recently for neural stem cell growth and differentiation. They are also used in interfaces with neurons, where they can detect neuronal electrical activity and also deliver electrical stimulation to these cells. The emerging picture is that carbon nanotubes do not have obvious adverse effects on mammalian health. Thus in the near future they could be used in brain–machine interfaces. PMID:19812974

Malarkey, Erik B.

2010-01-01

185

Carbon monoxide poisoning  

PubMed Central

Carbon monoxide poisoning is a significant cause of illness and death. Its protean symptoms probably lead to a gross underestimation of its true incidence. Low levels of carbon monoxide aggravate chronic cardiopulmonary problems, and high levels are associated with cardiac arrhythmias and cerebral edema. Patients who survive acute poisoning are at risk of delayed neurologic sequelae. The measurement of carboxyhemoglobin levels does not reveal the tissue levels of carbon monoxide but is useful in determining therapy. Treatment includes the monitoring and management of cardiac arrhythmias and oxygenation. Hyperbaric oxygenation is beneficial, but there are currently no definite criteria for its use. PMID:4027805

Dolan, Michael C.

1985-01-01

186

IMPACCT: Carbon Capture Technology  

SciTech Connect

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.

None

2012-01-01

187

Trees and Carbon  

NSDL National Science Digital Library

The transport and transformation of substances in the environment are known collectively as biogeochemical cycles. These global cycles involve the circulation of elements and nutrients that sustain both the biological and physical aspects of the environment. As an example, this discussion centers around the carbon cycle and how carbon is sequestered in trees. Students will perform an activity that replicates a case study in which the biomass of trees in a 15-acre plot of forest was calculated to determine the amount of carbon sequestered per acre.

John Pratte

188

40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.  

Code of Federal Regulations, 2012 CFR

... false Carbon monoxide and carbon dioxide analyzer specifications. 86...316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made...

2012-07-01

189

40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.  

Code of Federal Regulations, 2010 CFR

... false Carbon monoxide and carbon dioxide analyzer specifications. 86...316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made...

2010-07-01

190

40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.  

Code of Federal Regulations, 2013 CFR

... false Carbon monoxide and carbon dioxide analyzer specifications. 86...316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made...

2013-07-01

191

40 CFR 86.316-79 - Carbon monoxide and carbon dioxide analyzer specifications.  

Code of Federal Regulations, 2011 CFR

... false Carbon monoxide and carbon dioxide analyzer specifications. 86...316-79 Carbon monoxide and carbon dioxide analyzer specifications. (a) Carbon monoxide and carbon dioxide measurements are to be made...

2011-07-01

192

Authigenic Carbonate and the History of the Global Carbon Cycle  

NASA Astrophysics Data System (ADS)

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.

Schrag, Daniel P.; Higgins, John. A.; Macdonald, Francis A.; Johnston, David T.

2013-02-01

193

A novel carbon fiber based porous carbon monolith  

SciTech Connect

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).

Burchell, T.D.; Klett, J.W.; Weaver, C.E.

1995-06-01

194

Resistivity of Carbon-Carbon Composites Halved  

NASA Technical Reports Server (NTRS)

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 fibers in the samples were still intercalated after composite fabrication, they were subjected to X-ray diffraction. The composites containing intercalated graphite fibers showed much higher background scatter than that of pristine fibers, indicating the presence of bromine in the samples. More importantly, faint features indicative of intercalation were visible in the diffraction pattern, showing that the fibers were still intercalated.

Gaier, James R.

2004-01-01

195

Carbon Isotope Ratios in Belowground Carbon Cycle Processes  

Microsoft Academic Search

Abstract Analyses of carbon isotope ratios (?,C values of CO2effluxing from soils, but asof,yet a global,database,is lacking,with which,to test this prediction. Such a global,database,would be a useful input for global carbon cycle models,which,rely on ?values,to constrain source and sink relations. Keywords: global change, ecosystem processes, soil organic carbon, carbon isotope ratio, carbon cycle,

James R. Ehleringer; Nina Buchmann; Lawrence B. Flanagan

2000-01-01

196

Carbon in the Oceans  

NSDL National Science Digital Library

In this assignment, students in small groups are asked to interpret and explain a figure depicting one aspect of marine carbon biogeochemistry. Then a representative of each group explains the figure to the class.

Amy Townsend-Small

197

Ringed-Carbon Compounds  

NSDL National Science Digital Library

In this interactive activity adapted from NOVA, learn about alkaloids and steroids, both examples of compounds with carbon rings. Short videos with interviews,animations, and photographs are featured.

WGBH Educational Foundation

2007-02-12

198

Occult Carbon Monoxide Poisoning  

PubMed Central

A syndrome of headache, fatigue, dizziness, paresthesias, chest pain, palpitations and visual disturbances was associated with chronic occult carbon monoxide exposure in 26 patients in a primary care setting. A causal association was supported by finding a source of carbon monoxide in a patient's home, workplace or vehicle; results of screening tests that ruled out other illnesses; an abnormally high carboxyhemoglobin level in 11 of 14 patients tested, and abatement or resolution of symptoms when the source of carbon monoxide was removed. Exposed household pets provided an important clue to the diagnosis in some cases. Recurrent occult carbon monoxide poisoning may be a frequently overlooked cause of persistent or recurrent headache, fatigue, dizziness, paresthesias, abdominal pain, diarrhea and unusual spells. PMID:3825110

Kirkpatrick, John N.

1987-01-01

199

Carbon nanotubes: Fibrillar pharmacology  

NASA Astrophysics Data System (ADS)

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.

Kostarelos, Kostas

2010-10-01

200

Transport in Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

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.

Datta, S.; Xue, Yong-Qinag; Anantram, M. P.; Saini, Subhash (Technical Monitor)

1999-01-01

201

Carbon Monoxide Information Center  

MedlinePLUS Videos and Cool Tools

... Portable Generator-Related Deaths More CO Blogs Research & Statistics January 08, 2015 Non-Fire Carbon Monoxide Deaths ... Engine-Driven Tools View All CO-Related Injury Statistics and Technical Reports Inside CPSC: Recalls Safety Education ...

202

Carbon sequestration in soils  

SciTech Connect

The purpose of this article is to examine (a) the magnitude of the potential for carbon sequestration in the soil as a means of reducing carbon dioxide (CO{sub 2}) in the atmosphere, (b) some of the measures that might be used to achieve this potential, (c) the methods available for estimating carbon sequestration on a farm or regional level, (d) what is needed to achieve international consensus, and (e) additional information needs. This article is not presented as a definitive document but rather as an overview of where scientific opinion converges and where more work is needed. In addition, it aims to provoke discussion of the measures that can increase soil carbon sequestration and the policies that might be used to implement those measures.

Bruce, J.P. [Soil and Water Conservation Society, Ottawa, Ontario (Canada); Frome, M. [Soil and Water Conservation Society, Washington, DC (United States); Haites, E. [Margaree Consultants, Toronto, Ontario (Canada); Janzen, H. [Agriculture and Agri-Food Canada, Lethbridge, Alberta (Canada); Lal, R. [Ohio State Univ., Columbus, OH (United States). School of Natural Resources; Paustian, K. [Colorado State Univ., Fort Collins, CO (United States). Natural Resource Ecology Lab.

1999-01-01

203

Carbon Monoxide Poisoning  

MedlinePLUS

... minutes.** Consumers die when they improperly use gas generators, charcoal grills, and fuel-burning camping heaters and stoves inside their homes or in other enclosed or partiallyenclosed spaces during power outages. *** Preparedness Tips Install a carbon monoxide (CO) ...

204

Extrasolar Carbon Planets  

E-print Network

We suggest that some extrasolar planets planets and low-mass white dwarf planets are especially good candidate members of this new class of planets, but these objects could also conceivably form around stars like the Sun. This planet-formation pathway requires only a factor of two local enhancement of the protoplanetary disk's C/O ratio above solar, a condition that pileups of carbonaceous grains may create in ordinary protoplanetary disks. Hot, Neptune-mass carbon planets should show a significant paucity of water vapor in their spectra compared to hot planets with solar abundances. Cooler, less massive carbon planets may show hydrocarbon-rich spectra and tar-covered surfaces. The high sublimation temperatures of diamond, SiC, and other carbon compounds could protect these planets from carbon depletion at high temperatures.

Marc J. Kuchner; S. Seager

2005-05-02

205

Carbon Monoxide Safety  

MedlinePLUS

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

206

Carbon Monoxide (CO)  

MedlinePLUS

... stoves, and fireplaces; gas stoves; generators and other gasoline powered equipment; automobile exhaust from attached garages; and ... page ALERT!! Preventing Carbon Monoxide Poisoning from Small Gasoline-Powered Engines and Tools . (1996) This joint alert ...

207

Research Summary Carbon Additionality  

E-print Network

.1 and 12.5 of the Kyoto Protocol. The underlying rationale is to enable activities contributing further and evidence requirements. o consider implications of Kyoto Protocol/National GHG Inventory carbon accounting

208

GETTING CARBON CAPTURE AND STORAGE  

E-print Network

GETTING CARBON CAPTURE AND STORAGE TECHNOLOGIES TO MARKET BREAKING THE DEADLOCK Report of a Science: Carbon Capture and Storage © OECD/IEA 2009, fig. 1, p. 6 Figures 2 and 3 reprinted with permission from `UK Carbon storage and capture, where is it?' by Stuart Haszeldine, Professor of Carbon Capture

Haszeldine, Stuart

209

4, 1367, 2007 Modelling carbon  

E-print Network

BGD 4, 13­67, 2007 Modelling carbon overconsumption and extracellular POC formation M. Schartau et carbon overconsumption and the formation of extracellular particulate organic carbon M. Schartau1 , A Correspondence to: M. Schartau (markus.schartau@gkss.de) 13 #12;BGD 4, 13­67, 2007 Modelling carbon

Paris-Sud XI, Université de

210

Method for synthesizing carbon nanotubes  

DOEpatents

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.

Fan, Hongyou

2012-09-04

211

Carbon14 in tree rings  

Microsoft Academic Search

In order to investigate how reliably the carbon 14 content of tree rings reflects that of atmospheric carbon dioxide, two types of determinations were carried out: (1) carbon 14 determinations in annual rings from the beginning of this century until 1974 and (2) carbon 14 determinations in synchronous wood from the North American bristlecone pine and from European oak trees,

William F. Cain; Hans E. Suess

1976-01-01

212

Molecular Structure of Carbonic acid  

NSDL National Science Digital Library

The hypothetical acid formed with carbon dioxide and water; it is only in the H2CO3 form when in solution. This acid is found in everyday products, the most prominent of which include carbonated beverages. The conversion of carbonic acid into water and carbon dioxide in sodas is the reason the beverage looses the bubbling.

2002-09-10

213

Powdered Activated Carbon Adsorption  

Microsoft Academic Search

\\u000a Historically, the use of activated carbon has been limited to treatment applications for drinking water. In the past two decades,\\u000a more attention has been given to the potential use of activated carbons for wastewater treatment. The interest in such a process\\u000a has stemmed from the growing concern over the quality of rain water from which we get our potable water.

Yung-Tse Hung; Howard H. Lo; Lawrence K. Wang; Jerry R. Taricska; Kathleen Hung Li

214

Introduction to Carbon Nanotubes  

NASA Astrophysics Data System (ADS)

Carbon nanotubes are remarkable objects that look set to revolutionize the technological landscape in the near future. Tomorrow's society will be shaped by nanotube applications, just as silicon-based technologies dominate society today. Space elevators tethered by the strongest of cables; hydrogen-powered vehicles; artificial muscles: these are just a few of the technological marvels that may be made possible by the emerging science of carbon nanotubes.

Monthioux, Marc; Serp, Philippe; Flahaut, Emmanuel; Razafinimanana, Manitra; Laurent, Christophe; Peigney, Alain; Bacsa, Wolfgang; Broto, Jean-Marc

215

Amorphous Hydrogenated Carbon Nanofilm  

Microsoft Academic Search

Amorphous hydrogenated carbon (a-C:H) nanofilm is a metastable form of amorphous carbon with significant sp3 bonding. a-C:H\\u000a is a semiconductor with a high mechanical hardness, chemical inertness, and optical transparency. This chapter will describe\\u000a the deposition methods, deposition mechanisms, characterization methods, electronic structure, gap states, defects, doping,\\u000a luminescence, field emission, mechanical properties, and some applications of a-C:H. The films have

Dechun Ba; Zeng Lin

216

Prokaryotic carbonic anhydrases  

Microsoft Academic Search

Carbonic anhydrases catalyze the reversible hydration of CO2 [CO2+H2O?HCO3?+H+]. Since the discovery of this zinc (Zn) metalloenzyme in erythrocytes over 65 years ago, carbonic anhydrase has not only been found in virtually all mammalian tissues but is also abundant in plants and green unicellular algae. The enzyme is important to many eukaryotic physiological processes such as respiration, CO2 transport and

Kerry S Smith; James G Ferry

2000-01-01

217

Material Science of Carbon  

NASA Astrophysics Data System (ADS)

Carbon is a ubiquitous material that is essential for the functioning of modern society. Because carbon can exist in a multitude of forms, it can be tailored to possess practically any property that might be required for a specific application. The list of applications is very extensive and includes: aircraft brakes, electrodes, high temperature molds, rocket nozzles and exit cones, tires, ink, nuclear reactors and fuel particles, filters, prosthetics, batteries and fuel cells, airplanes, and sporting equipment.

Hoffman, Wesley P.

218

Sedimentary Rocks: Carbonate Rocks  

NSDL National Science Digital Library

Sedimentary Rocks: Carbonate Rocks is a course handout meant to accompany the discussion of chemical and biochemical sedimentary rocks. Rock composition is broken into the main categories of limestone and dolostone. Depositional conditions are discussed, including the topics of coral reefs, plankton, and carbonate compensation depth (CCD). There are a few photographs, which display calcareous algae. Links are provided to the online Physical Geology resources at Georgia Perimeter College.

Pamela Gore

219

Functionalization of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

These project will explore the functionalization of carbon nanotubes via the formation of molecular complexes with perylene diimide based systems. It is anticipated that these complexes would be soluble in organic solvent and enable the homogenous dispersion of carbon nanotubes in polymer films. Molecular complexes will be prepared and characterized using standard spectroscopic and thermal analytical techniques. Polymer films will be prepared with these complexes and their properties (electrical and thermal conductivity, mechanical properties, stability) evaluated.

Webber, Stephen E.

2003-01-01

220

Lead carbonate scintillator materials  

DOEpatents

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.

Derenzo, S.E.; Moses, W.W.

1991-05-14

221

Nanopumping using carbon nanotubes.  

SciTech Connect

A new 'nanopumping' effect consisting of the activation of an axial gas flow inside a carbon nanotube by producing Rayleigh traveling waves on the nanotube surface is predicted. The driving force for the new effect is the friction between the gas particles and the nanotube walls. A molecular dynamics simulation of the new effect was carried out showing macroscopic flows of atomic and molecular hydrogen and helium gases in a carbon nanotube.

Insepov, Z.; Wolf, D.; Hassanein, A.; Mathematics and Computer Science; INL

2006-01-01

222

Nanopumping using carbon nanotubes.  

PubMed

A new "nanopumping" effect consisting of the activation of an axial gas flow inside a carbon nanotube by producing Rayleigh traveling waves on the nanotube surface is predicted. The driving force for the new effect is the friction between the gas particles and the nanotube walls. A molecular dynamics simulation of the new effect was carried out showing macroscopic flows of atomic and molecular hydrogen and helium gases in a carbon nanotube. PMID:16967997

Insepov, Zeke; Wolf, Dieter; Hassanein, Ahmed

2006-09-01

223

Carbon dioxide removal process  

DOEpatents

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.

Baker, Richard W.; Da Costa, Andre R.; Lokhandwala, Kaaeid A.

2003-11-18

224

Method of manufacturing carbon nanotubes  

NASA Technical Reports Server (NTRS)

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.

Benavides, Jeanette M. (Inventor); Leidecker, Henning W. (Inventor); Frazier, Jeffrey (Inventor)

2004-01-01

225

Carbon Characterization Laboratory Report  

SciTech Connect

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.

David Swank; William Windes; D.C. Haggard; David Rohrbaugh; Karen Moore

2009-03-01

226

Functionalized Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

227

Carbon based prosthetic devices  

SciTech Connect

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.

Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

1998-12-31

228

Thermal oxidation of carbon nanomaterials  

NASA Astrophysics Data System (ADS)

The process of the thermal oxidation of various carbon nanomaterials (multiwalled carbon nanotubes, carbon black, nanoporous carbon and graphite) used in the catalytic layers of electrochemical energy converters (electrolyzers, fuel cells) has been studied. The thermal stability of these materials has been determined. Relationships between the structural characteristics of carbon nanomaterials and the parameters of their thermal oxidation in air have determined using the methods of differential thermal analysis and adsorption-structure analysis.

Glebova, N. V.; Nechitailov, A. A.; Kukushkina, Yu. A.; Sokolov, V. V.

2011-05-01

229

Mechanistical studies on the formation and destruction of carbon monoxide (CO), carbon dioxide (CO2), and carbon trioxide (CO3)  

E-print Network

Mechanistical studies on the formation and destruction of carbon monoxide (CO), carbon dioxide (CO2 monoxide (CO), carbon dioxide (CO2), and molecular oxygen (O2) with varying carbon-to-oxygen ratios from 1 and destruction pathways of carbon monoxide (CO), carbon dioxide (CO2), and carbon trioxide (CO3

Kaiser, Ralf I.

230

Molten carbonate fuel cell cathode with mixed oxide coating  

DOEpatents

A molten carbonate fuel cell cathode having a cathode body and a coating of a mixed oxygen ion conductor materials. The mixed oxygen ion conductor materials are formed from ceria or doped ceria, such as gadolinium doped ceria or yttrium doped ceria. The coating is deposited on the cathode body using a sol-gel process, which utilizes as precursors organometallic compounds, organic and inorganic salts, hydroxides or alkoxides and which uses as the solvent water, organic solvent or a mixture of same.

Hilmi, Abdelkader; Yuh, Chao-Yi

2013-05-07

231

Measurement of carbon capture efficiency and stored carbon leakage  

DOEpatents

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.

Keeling, Ralph F.; Dubey, Manvendra K.

2013-01-29

232

Microbially mediated carbon mineralization: Geoengineering a carbon-neutral mine  

NASA Astrophysics Data System (ADS)

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.

Power, I. M.; McCutcheon, J.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.; Southam, G.

2013-12-01

233

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

234

Carbon fuel particles used in direct carbon conversion fuel cells  

DOEpatents

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.

Cooper, John F. (Oakland, CA); Cherepy, Nerine (Oakland, CA)

2012-01-24

235

Carbon Fuel Particles Used in Direct Carbon Conversion Fuel Cells  

DOEpatents

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.

Cooper, John F. (Oakland, CA); Cherepy, Nerine (Oakland, CA)

2008-10-21

236

Carbon fuel particles used in direct carbon conversion fuel cells  

DOEpatents

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.

Cooper, John F. (Oakland, CA); Cherepy, Nerine (Oakland, CA)

2011-08-16

237

Carbon fuel particles used in direct carbon conversion fuel cells  

DOEpatents

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.

Cooper, John F.; Cherepy, Nerine

2012-10-09

238

Chemically modified carbonic anhydrases useful in carbon capture systems  

DOEpatents

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.

Novick, Scott; Alvizo, Oscar

2013-01-15

239

Chemically modified carbonic anhydrases useful in carbon capture systems  

SciTech Connect

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.

Novick, Scott J; Alvizo, Oscar

2013-10-29

240

Metal-to-ligand alkyl migration inducing carbon-sulfur bond cleavage in dialkyl yttrium complexes supported by thiazole-containing amidopyridinate ligands: synthesis, characterization, and catalytic activity in the intramolecular hydroamination reaction.  

PubMed

Neutral Y(III) dialkyl complexes supported by tridentate N(-) ,N,N monoanionic methylthiazole- or benzothiazole-amidopyridinate ligands have been prepared and completely characterized. Studies on their stability in solution revealed progressive rearrangement of the coordination sphere in the benzothiazole-containing system through an unprecedented metal-to-ligand alkyl migration and subsequent thiazole ring opening. Attempts to synthesize hydrido species from the dialkyl precursor led to the generation of a dimeric yttrium species stabilized by a trianionic N(-) ,N,N(-) ,S(-) ligand as the result of metal-to-ligand hydride migration with chemoselective thiazole ring opening and subsequent dimerization through intermolecular addition of the residual Y?H group to the imino fragment of a second equivalent of the ring-opened intermediate. DFT calculations were used to elucidate the thermodynamics and kinetics of the process, in support of the experimental evidence. Finally, all isolated yttrium complexes, especially their cationic forms prepared by activation with the Lewis acid Ph3 C(+) [B(C6 F5 )4 ](-) , were found to be good candidate catalysts for intramolecular hydroamination/cyclization reactions. Their catalytic performance with a number of primary and secondary amino alkenes was assessed. PMID:24616174

Lyubov, Dmitry M; Luconi, Lapo; Rossin, Andrea; Tuci, Giulia; Cherkasov, Anton V; Fukin, Georgy K; Giambastiani, Giuliano; Trifonov, Alexander A

2014-03-17

241

CarbonTracker  

NSDL National Science Digital Library

This portal provides information about the National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory (ERSL) CarbonTracker, a system to keep track of carbon dioxide uptake and release at the Earth's surface over time. CarbonTracker produces model predictions of atmospheric CO2 mole fractions, to be compared with the observed atmospheric CO2 mole fractions. Materials available at the site include CO2 flux maps, flux time series graphs, carbon 'weather' maps, and CO2 concentration time series graphs. A download (FTP) page provides access to datasets on 3-D CO2 mole fractions, weekly fluxes, atmospheric CO2 observations, and to the CarbonTracker source code. There is also a link to the Interactive Atmospheric Data Visualization (IADV) tool, a data explorarion tool that enables users to view all data including near real-time preliminary measurement results, obtain details about each sampling location, manipulate and compare NOAA ESRL datasets, create custom graphs, and view their plots online or save them for later use. Other materials include subscription information for an email list, a glossary, and a bibliography.

242

Carbon Fibers Conductivity Studies  

NASA Technical Reports Server (NTRS)

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.

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

1980-01-01

243

Orbiting Carbon Observatory  

NASA Technical Reports Server (NTRS)

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.

Miller, Charles E.

2005-01-01

244

Carbon Cycle: Exchanging Carbon Dioxide between the Atmosphere and Ocean  

NSDL National Science Digital Library

This lab investigates the exchange of carbon dioxide between the atmosphere and the ocean's surface. It is based on the fact that carbon dioxide dissolves in the ocean and provides the source of that plants and plankton living in the ocean rely on for photosynthesis. Students will discover that the amount of carbon dioxide the ocean can contain depends on the temperature of the water and its salinity (whether it is sea water or fresh water) and that cold water can hold more carbon dioxide in solution than warm water. They will observe that when carbon dioxide dissolves in water, it forms carbonic acid which makes the water acidic, and they will test for the acidity caused by the presence of dissolved carbon dioxide using Universal Indicator, which turns yellow when the solution is acidic. This activity tests whether sea water or fresh water absorbs more carbon dioxide.

245

Carbon Cycle and Life  

NSDL National Science Digital Library

In this lesson, learners explore the steps in the carbon cycle and draw conclusions about the importance of the carbon cycle in the planetary temperature system. The lesson models scientific inquiry using the 5E instructional model and includes teacher notes, prerequisite concepts, common misconceptions, student journal and reading. This is lesson six in the Astro-Venture Geology Training Unit that was developed to increase students' awareness of and interest in astrobiology and the many career opportunities that utilize science, math and technology skills. The lessons are designed for educators to use with the Astro-Venture multimedia modules.

2012-08-03

246

Ultrahard carbon nanocomposite films  

SciTech Connect

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.

SIEGAL,MICHAEL P.; TALLANT,DAVID R.; PROVENCIO,PAULA P.; OVERMYER,DONALD L.; SIMPSON,REGINA L.; MARTINEZ-MIRANDA,L.J.

2000-01-27

247

Carbon Capture and Storage  

SciTech Connect

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 key documents written in the last three years that provide information on the status, economics, technology, and impact of CCS. These are cited throughout this text and identified as key references at the end of this manuscript. When coupled with improvements in energy efficiency, renewable energy supplies, and nuclear power, CCS help dramatically reduce current and future emissions (US CCTP 2005, MIT 2007). If CCS is not available as a carbon management option, it will be much more difficult and much more expensive to stabilize atmospheric CO{sub 2} emissions. Recent estimates put the cost of carbon abatement without CCS to be 30-80% higher that if CCS were to be available (Edmonds et al. 2004).

Friedmann, S

2007-10-03

248

Carbon wastewater treatment process  

NASA Technical Reports Server (NTRS)

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.

Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

1974-01-01

249

Carbon films from polyacrylonitrile  

SciTech Connect

Polyacrylonitrile (PAN) films have been fabricated by both spin and solvent casting techniques, and pyrolyzed to produce carbon films in the thickness range of 200--50 000 A. These films have higher electrical conductivities than carbon films produced from most other precursors at similar temperatures. The chemical structure of the films at different stages of processing was investigated by UV, IR, Raman, and XPS spectroscopies. An extra degree of control over the final electrical conductivity was obtained by varying the PAN content of copolymer precursors. Oxidation rates and an activation energy were determined. Finally, processing techniques are described which allow both dry and wet film transfer and lithographic patterning.

Renschler, C.L.; Sylwester, A.P.; Salgado, L.V.

1989-03-01

250

Nanopumping Using Carbon Nanotubes  

Microsoft Academic Search

ABSTRACT A new,“nanopumping” effect consisting of the activation of an axial gas flow inside a carbon,nanotube,by producing,Rayleigh traveling waves on the nanotube,surface is predicted. The driving force for the new,effect is the friction between,the gas particles and the nanotube,walls. A molecular,dynamics,simulation of the new,effect was,carried out showing,macroscopic,flows of atomic and molecular,hydrogen,and helium gases,in a carbon,nanotube. Actuation of a fluid flow

Zeke Insepov; Dieter Wolf; Ahmed Hassanein

2006-01-01

251

Carbon Dioxide Exercise  

NSDL National Science Digital Library

In this activity, students work in groups, plotting carbon dioxide concentrations over time on overheads and estimating the rate of change over five years. Stacked together, the overheads for the whole class show an increase on carbon dioxide over five years and annual variation driven by photosynthesis. This exercise enables students to practice basic quantitative skills and understand how important sampling intervals can be when studying changes over time. A goal is to see how small sample size may give incomplete picture of data.

Randy Richardson

252

Pitch carbon microsphere composite  

NASA Technical Reports Server (NTRS)

Petroleum pitch carbon microspheres were prepared by flash heating emulsified pitch and carbonizing the resulting microspheres in an inert atmosphere. Microsphere composites were obtained from a mixture of microspheres and tetraester precursor pyrrone powder. Scanning electron micrographs of the composite showed that it was an aggregate of microspheres bonded together by the pyrrone at the sphere contact points, with voids in and among the microspheres. Physical, thermal, and sorption properties of the composite are described. Composite applications could include use as a honeycomb filler in elevated-temperature load-bearing sandwich boards or in patient-treatment tables for radiation treatment of tumors.

Price, H. L.; Nelson, J. B.

1977-01-01

253

The reduction of carbon-carbon multiple bond systems  

E-print Network

THE REDUCTION OF CARBON-CARBON MULTIPLE BOND SYSTEMS A Thesis By Donald Roy Ferguson Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1965... CHEMISTRY THE REDUCTION OF CARBON-CARBON MULTIPLE BOND SYSTEMS A Thesis By Donald Roy Ferguson Approved as to style and content by; (Chairman of Committee) (H of epar (M er) (Member) (Memb ) (Member) August 1965 Acknowledgement For his direction...

Ferguson, Donald Roy

1965-01-01

254

Activated carbon catalyzing the formation of carbon nanotubes  

Microsoft Academic Search

Activated carbon (AC), a common carbon material, is employed as catalyst to synthesize carbon nanotubes (CNTs) through chemical vapor deposition (CVD) and detonation-assisted CVD methods. The results show AC can effectively catalyze CNT formation. From the microscopic observations on morphologies and structures of the formed intermediates, it is found that carbon-catalyzed CNT formation follows particle-wire-tube stepwise evolution mechanism, in which

Jinling Song; Shouai Feng; Jianghong Zhao; Jianfeng Zheng; Zhenping Zhu

2010-01-01

255

Potassium intercalation of carbon onions ‘opened’ by carbon dioxide treatment  

Microsoft Academic Search

The potassium intercalation of onion-like carbon (OLC) samples consisting of aggregates of carbon onions is studied with photoemission spectroscopy. OLC samples were initially prepared by annealing nanodiamonds (3–20nm in diameter) at 1800K in vacuum. The resulting OLC consists of closed fullerene-like shells. The ‘closed’ OLC was subsequently treated with carbon dioxide at 1020K in order to open the carbon shells

Yu. V. Butenko; Amit K. Chakraborty; N. Peltekis; S. Krishnamurthy; V. R. Dhanak; M. R. C. Hunt; L. Šiller

2008-01-01

256

Deep Recycling of Carbon  

NASA Astrophysics Data System (ADS)

While most of the subducted H2O is recycled at shallow and subarc depths, carbon is less readily mobilized and susceptive to complex redox processes involving CO2 in solids, fluids and melts, elemental carbon, Fe- and Si- carbides, and methane. Here I review the various ways of recycling carbon during subduction and present a spectrum of possible reaction products in the mantle. Metamorphic reactions liberate <20% of the subducted CO2 to the subarc region (Connolly 2005, EPSL). Larger amounts might be mobilized through (sediment) melting. Although the wet pelite solidus is only shifted by 30-50 oC (at 3 GPa) with carbonates, the latter remain stable with melts that are saturated in a H2O+CO2-fluid. Complete dissolution of carbonates requires temperatures above any predicted subduction geotherm. Carbonated sediments yield CO2-rich phonolites to 5 GPa but carbonatites at higher pressures. The silicate melts become increasingly potassic with pressure, while the alkali-rich carbonatites have their highest K/Na at 8 GPa, slightly decreasing to 13 GPa and become sodic with the disappearance of residual cpx at ~16 GPa. What may happen when carbonated pelite derived melts migrate into the mantle is illustrated in Central Italy: in this case, it can be experimentally demonstrated that hybridization of ultrapotassic phonolitic melts with ~2 wt% H2O and ~6 wt% CO2 in the mantle results in the primitive parents of the ultrapotassic kamafugite suites which have ~43 wt% SiO2. Hence, despite a crustal isotopic signature of C, O, and Sr in these rocks, the CO2 of the Italian magmatism does not stem from assimilation in the crust but from melts derived from subducted marine carbonates mixed with pelagic clays and then reacted in the mantle. The migration of CO2-bearing fluids and melts into the mantle may lead to a redox-shock. Where high liquid/mantle ratios prevail, carbonatites rest in their oxidized form and may only freeze in relatively cold lithospheric keels where they form metasomatic zones prone to generate kimberlites in the context of a much later remelting event. Where the redox-capacity of the oxidized crust-derived material is subequal to the reduced mantle, iron carbides are to be expected. The eutectic in the Fe-Ni-C system is at lower temperatures than the mantle adiabat, leading to the distinct possibility that such zones entrained in global mantle convection will contain ~1% of eutectic Fe-C-melt. When the amount of subduction derived CO2 is small compared to the redox capacity of a metal bearing reduced mantle, diamond will form, but diamond itself is not truly reducing at high pressures. The most extreme reducing case leads to moissanite (found together with diamond), which isotopic signature implies involvement of organically derived carbon. Moissanite (SiC) only forms at fO2 <6-8 log units below iron-wustite and coexists with mantle silicates that have an XMg of 0.995-0.998. Our calculations show that a fluid or melt with a bulk, which is slightly more reduced than the CO2-H2O-tieline in C-O-H, may evolve to ultra-reduced residual C-H-rich fluids through removal of CO2 (through carbonate precipitation) followed by removal of H2O (through hydrous silicate formation). As SiC may only be in grain scale equilibrium with the mantle and requires a protracted fluid-fractionation, we propose that SiC is generally a low temperature phase formed from originally already reducing fluids involving organic carbon and hence subduction.

Schmidt, M. W.

2012-12-01

257

Carbon accounting and carbon footprint – more than just diced results?  

Microsoft Academic Search

Purpose – The purpose of this paper is to discuss the growing public interest in climate protection and the desire for climate-friendly consumption which has led to a previously unimagined demand for Carbon Labels on products and various approaches to calculating the carbon footprint of firms or individual products. Design\\/methodology\\/approach – A principal problem in calculating the carbon footprint is

Mario Schmidt

2009-01-01

258

Cumulative Carbon and Just Allocation of the Global Carbon Commons  

E-print Network

America, and in particular the United States, has a strong moral obligation to take the lead in actions of carbon emitted in the form of carbon dioxide by activities such as fossil fuel burning and deforestation the question of fair allocation of carbon emissions amongst nations or other emitting units. It is concluded

Pierrehumbert, Raymond

259

Management practices affects soil carbon dioxide emission and carbon storage  

Technology Transfer Automated Retrieval System (TEKTRAN)

Agricultural practices contribute about 25% of total anthropogenic carbon dioxide emission, a greenhouse gas responsible for global warming. Soil can act both as sink or source of atmospheric carbon dioxide. Carbon dioxide fixed in plant biomass through photosynthesis can be stored in soil as organi...

260

Method of Manufacturing Carbon Fiber Reinforced Carbon Composite Valves  

NASA Technical Reports Server (NTRS)

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.

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

1998-01-01

261

Australian carbon dust emission: a carbon accounting omission?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Erosion preferentially removes the finest carbon- and nutrient-rich soil fractions, and consequently its role may be significant within terrestrial carbon (C) cycles. However, the impacts of wind erosion on soil organic carbon redistribution are not considered in most SOC models, or within the Austr...

262

Adsorption and migration of carbon adatoms on zigzag carbon nanotubes  

E-print Network

Adsorption and migration of carbon adatoms on zigzag carbon nanotubes A.V. Krasheninnikov a,*, K of single-walled zigzag carbon nanotubes. We demonstrate that the adatoms form strong covalent bonds and migration barrier depend on the nanotube diameter and chirality. The migration barriers, being in the range

Krasheninnikov, Arkady V.

263

SYNTHESIS OF CARBONATED FATTY METHYL ESTERS USING SUPERCRITICAL CARBON DIOXIDE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The two step syntheses of the cyclic carbonates: carbonated methyl oleate (CMO) and carbonated methyl linoleate (CML) are reported. First, synthesis of the epoxide through well precedented chemical reaction of unsaturated fatty methyl esters with hydrogen peroxide and formic acid is performed. Nex...

264

IMPROVED SYNTHESIS OF CARBONATED SOYBEAN OIL IN SUPERCRITICAL CARBON DIOXIDE  

Technology Transfer Automated Retrieval System (TEKTRAN)

Carbonates from oleochemical origin have shown recent promise for use in the cosmetics, filter, and detergent industries. Carbonates may also form building blocks for polymeric materials. Especially of interest are cyclic carbonates, which upon addition to an amine, form a non-isocyanate urethane....

265

Determination of carbonate carbon in geological materials by coulometric titration  

USGS Publications Warehouse

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.

Engleman, E.E.; Jackson, L.L.; Norton, D.R.

1985-01-01

266

Carbon Currency: The Credits and Debits of Carbon Emissions Trading  

NSDL National Science Digital Library

NOVA Australia, an initiative of the Australian Academy of Science, posts new feature articles regularly. 2000 publications include "Carbon currency: the credits and debits of carbon emissions trading" (discussing carbon emissions trading and whether trading can limit the enhanced greenhouse effect).

2000-01-01

267

Calcium carbonate with magnesium overdose  

MedlinePLUS

The combination of calcium carbonate and magnesium is commonly found in antacids, which are medicines that provide heartburn relief. Calcium carbonate with magnesium overdose occurs when someone accidentally or ...

268

Carbon Monoxide: The Silent Killer  

MedlinePLUS

... Travel & Motor Vehicle Safety En Español Holiday & Seasonal Carbon Monoxide — What You Can't See or Smell ... You Emergency physicians see the tragic consequences of carbon monoxide poisoning each year, especially during the winter ...

269

Dewatering Peat With Activated Carbon  

NASA Technical Reports Server (NTRS)

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.

Rohatgi, N. K.

1984-01-01

270

Sensor applications of carbon nanotubes  

E-print Network

A search of published research on sensing mechanisms of carbon nanotubes was performed to identify applications in which carbon nanotubes might improve on current sensor technologies, in either offering improved performance, ...

Rushfeldt, Scott I

2005-01-01

271

AUSTRALIA'S CARBON FOOTPRINT  

Microsoft Academic Search

This paper gives an overview of the construction techniques and methods used to assign greenhouse gas accounts to industry sectors and of the use of input–output analysis to subsequently calculate the carbon footprint of Australia. The work is motivated by the introduction of an emissions-trading scheme in Australia, and by the need for policy to be developed around the direct

Richard Wood; Christopher J. Dey

2009-01-01

272

GLOBAL TERRESTRIAL CARBON CYCLE  

EPA Science Inventory

There is great uncertainty with regard to the future role of the terrestrial biosphere in the global carbon cycle, arising from both an inadequate understanding of current pools and fluxes as well as the potential effects of rising atmospheric concentrations of CO, on natural eco...

273

Carbon cloth supported electrode  

DOEpatents

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.

Lu, Wen-Tong P. (Upper St. Clair, PA); Ammon, Robert L. (Baldwin both of, PA)

1982-01-01

274

Populations of Carbon Stars  

NASA Astrophysics Data System (ADS)

Carbon stars in the Galaxy do not constitute a single family, but may be divided over several types with distinctive spectroscopic and photometric properties. A subtype of the N stars, characterised by high velocities and weak CN bands, may have been captured by the Milky Way from a cannibalised dwarf galaxy.

Lloyd Evans, T.

2011-09-01

275

Carbon nanotube electronics  

Microsoft Academic Search

We evaluate the potential of carbon nanotubes (CNTs) as the basis for a new nanoelectronic technology. After briefly reviewing the electronic structure and transport properties of CNTs, we discuss the fabrication of CNT field-effect transistors (CNTFETs) formed from individual single-walled nanotubes (SWCNTs), SWCNT bundles, or multiwalled (MW) CNTs. The performance characteristics of the CNTFETs are discussed and compared to those

PHAEDON AVOURIS; JOERG APPENZELLER; RICHARD MARTEL; SHALOM J. WIND

2003-01-01

276

Carbon Nanotube Quantum Resistors  

Microsoft Academic Search

The conductance of multiwalled carbon nanotubes (MWNTs) was found to be quantized. The experimental method involved measuring the conductance of nanotubes by re- placing the tip of a scanning probe microscope with a nanotube fiber, which could be lowered into a liquid metal to establish a gentle electrical contact with a nanotube at the tip of the fiber. The conductance

Stefan Frank; Philippe Poncharal; Z. L. Wang; Walt A. de Heer

1998-01-01

277

Changing Planet: Black Carbon  

NSDL National Science Digital Library

This video addresses two ways in which black carbon contributes to global warming - when in the atmosphere, it absorbs sunlight and generates heat, warming the air; when deposited on snow and ice, it changes the albedo of the surface. The video is effective in communicating about a problem frequently underrepresented in discussions of climate change and also public health.

NBC Learn

278

GRANULAR ACTIVATED CARBON INSTALLATIONS  

EPA Science Inventory

This paper presents a compilation and summary of design criteria, performance, and cost data from 22 operating municipal and industrial granular activated carbon (GAC) installations that treat water and wastewater or process food and beverage products. Guidance for using this inf...

279

Carbon-Fuelled Future  

SciTech Connect

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.

Appel, Aaron M.

2014-09-12

280

From Coffee to Carbon  

NSDL National Science Digital Library

In this activity, learners place cards featuring biological structures in order by their relative size from largest to smallest. The cards feature structures ranging from the carbon atom (340 pm) to a skin cell (30 ?m) to a coffee bean (8 mm). This activity can also be used as a formative assessment or an anticipatory set.

Molly Malone

2008-01-01

281

Carbon smackdown: wind warriors  

SciTech Connect

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.

Glen Dahlbacka of the Accelerator & Fusion Research Division and Ryan Wiser of the Environmental Energy Technologies Division are the speakers.

2010-07-21

282

Mass carbon monoxide poisoning  

PubMed Central

The largest occurrence of carbon monoxide poisoning in Britain demonstrates the potential for mass accidental poisoning. It emphasises the need for strict public health controls and the importance of good liaison between emergency services to ensure that such events are quickly recognised and that the necessary resources are organised. PMID:10658990

McGuffie, C; Wyatt, J; Kerr, G; Hislop, W

2000-01-01

283

Carbon smackdown: smart windows  

ScienceCinema

August 3, 2010 Berkeley Lab talk: In the fourth of five Carbon Smackdown matches, Berkeley Lab researchers Delia Milliron of the Materials Sciences Division and Stephen Selkowitz of the Environmental Energy Technologies Division talk about their work on energy-saving smart windows.

Delia Milliron

2010-09-01

284

Life without Carbon?  

NASA Astrophysics Data System (ADS)

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.

Cuntz, Manfred; Williams, Peter E.

2006-05-01

285

A Strict Carbon Diet  

NSDL National Science Digital Library

This short video follows San Francisco inventor and engineer Saul Griffith as he determines his family's carbon footprint and develops a special cargo bike to further reduce his individual footprint. This video highlights innovation, creativity, and design as solutions to problems. The overall message is inspiring and proactive.

Doug (producer) Hamilton

286

Carbon smackdown: wind warriors  

ScienceCinema

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.

Glen Dahlbacka of the Accelerator & Fusion Research Division and Ryan Wiser of the Environmental Energy Technologies Division are the speakers.

2010-09-01

287

Transmissivity of carbon monoxide  

NASA Technical Reports Server (NTRS)

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.

Drayson, S. R.; Tallamraju, R.; Chaney, L. W.

1973-01-01

288

Carbon arc solar simulator  

Microsoft Academic Search

Measurements of the spatial, spectral, and temporal characteristics of the beam irradiance of a carbon arc solar simulator are reported. Pyroelectric radiometer measurements of total irradiance and spectroradiometer measurements of spectral irradiance are presented. The solar simulator spectral irradiance is compared with the ASTM standard AM 1.5 global solar spectral irradiance over a wavelength region of 300-2500 nm. The suitability

Robert A. Olson; Jack H. Parker

1991-01-01

289

Hydrothermal carbonization of microalgae  

Microsoft Academic Search

Hydrothermal carbonization is a process in which biomass is heated in water under pressure to create a char product. With higher plants, the chemistry of the process derives primarily from lignin, cellulose and hemicellulose components. In contrast, green and blue-green microalgae are not lignocellulosic in composition, and the chemistry is entirely different, involving proteins, lipids and carbohydrates (generally not cellulose).

Steven M. Heilmann; H. Ted Davis; Lindsey R. Jader; Paul A. Lefebvre; Michael J. Sadowsky; Frederick J. Schendel; Marc G. von Keitz; Kenneth J. Valentas

2010-01-01

290

Atmospheric Carbon Dioxide  

NSDL National Science Digital Library

This figure, the famous Keeling Curve, shows the history of atmospheric carbon dioxide concentrations as directly measured at Mauna Loa, Hawaii. This curve is an essential piece of evidence that shows the increased greenhouse gases that cause recent increases in global temperatures.

Robert A. Rohde

291

Carbon Dioxide Increases  

NSDL National Science Digital Library

In this problem set, learners will analyze the Keeling Curve showing carbon dioxide concentration in the atmosphere since 1985 to answer a series of questions. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

292

Polyimide/carbon Nanocomposites  

NASA Technical Reports Server (NTRS)

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.

Harris, Frank W.

2003-01-01

293

Carbon Additionality: Discussion Paper  

E-print Network

is to distinguish activities which further contribute to climate change mitigation from those which, although.2 Underlying Rationale 12 3. Tests, Methodologies and Evidence 12 3.1 Legal, Regulatory & Institutional TestsFix Standard (CFS) 28 Climate, Community and Biodiversity Standard (CCBS) 28 Forest Carbon Standard (FCS) 28

294

Poly (Carbonate-Mide) Polymer  

NASA Technical Reports Server (NTRS)

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.

St.clair, T. L. (inventor); Maudgal, S. (inventor); Pratt, J. R. (inventor)

1986-01-01

295

Carbon aerogels for electrochemical applications  

Microsoft Academic Search

A major advantage of highly crosslinked, organic aerogels is the ability to transform many of these materials into electrically conductive carbon aerogels. Carbon aerogels have been formed as monoliths, microspheres, irregularly-shaped powders, and thin film composites. In all cases, the carbon aerogels retain their high surface area (400–800 m2\\/g) and ultrafine cell\\/pore size (<100 nm). Carbon aerogels are being examined

R. W. Pekala; J. C. Farmer; C. T. Alviso; T. D. Tran; S. T. Mayer; J. M. Miller; B. Dunn

1998-01-01

296

Carbon nanotube array based sensor  

DOEpatents

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.

Lee, Christopher L.; Noy, Aleksandr; Swierkowski, Stephan P.; Fisher, Karl A.; Woods, Bruce W.

2005-09-20

297

Templated Growth of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

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.

Siochik Emilie J. (Inventor)

2007-01-01

298

Poly(carbonate-imide) polymer  

NASA Technical Reports Server (NTRS)

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.

St. Clair, Terry L. (Inventor); Maudgal, Shubha (Inventor); Pratt, J. Richard (Inventor)

1987-01-01

299

14 April 2001 tmospheric carbon dioxide  

E-print Network

emissions is through increased carbon sequestration into forests. In a large-scale assessment, Birdsey- ing carbon sequestration in southern forests. Carbon sequestration via southern pine forests may policy commitments. Keywords: carbon sequestration; southern pine forests ABSTRACT MEETING GLOBAL POLICY

Teskey, Robert O.

300

Model-based estimation of the global carbon budget and its uncertainty from carbon dioxide and carbon isotope records  

E-print Network

Model-based estimation of the global carbon budget and its uncertainty from carbon dioxide and the terrestrial biosphere based on carbon dioxide and carbon isotope records, and prior information on model of carbon dioxide and the resulting atmospheric concentration of carbon dioxide determined from the behavior

Jain, Atul K.

301

Carbon Fiber Risk Analysis. [conference  

NASA Technical Reports Server (NTRS)

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.

1979-01-01

302

Globalizing carbon lock-in  

Microsoft Academic Search

This paper extends the arguments surrounding carbon lock-in elaborated in Unruh (Energy Policy 28 (2000) 817; 30 (2002) 317) to countries currently undergoing industrialization. It argues that, for numerous reasons, industrializing countries are unlikely to leapfrog carbon intensive energy development. On the contrary, carbon lock-in may be globalizing and could further constrain climate change mitigation options. It is then argued

Gregory C. Unruh; Javier Carrillo-Hermosilla

2006-01-01

303

1, 167193, 2004 Terrestrial carbon  

E-print Network

BGD 1, 167­193, 2004 Terrestrial carbon budget at country-scale I. A. Janssens et al. Title Page Biogeosciences Discussions is the access reviewed discussion forum of Biogeosciences The carbon budget.janssens@ua.ac.be) 167 #12;BGD 1, 167­193, 2004 Terrestrial carbon budget at country-scale I. A. Janssens et al. Title

Paris-Sud XI, Université de

304

Carbon: electrochemical and physicochemical properties  

Microsoft Academic Search

This book provides a reference source for the application and study of carbon materials in electrochemistry. The first four chapters deal with the physical properties and chemical reactivity of carbon in its many forms. The remaining chapters focus on the role of carbon materials in electrode and electrochemistry applications. The book concludes with a complete listing of recently assigned patents

K Kinoshita

1988-01-01

305

Carbon Cloth Supports Catalytic Electrodes  

NASA Technical Reports Server (NTRS)

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.

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

1983-01-01

306

Atomic Structure of Carbon Nanomaterials  

E-print Network

Materials #12;Atomistic model of pyrolytic carbons Jean-Marc Leyssale et al. APPLIED PHYSICS LETTERS 95Atomic Structure of Carbon Nanomaterials: Physics and Characterization Jian-Min (Jim) Zuo;Outline of This Talk I. Structure of carbon nanomaterials II. Electron diffraction III. Growth

Zuo, Jian-Min "Jim"

307

Carbon Nanotubes for Data Processing  

E-print Network

Carbon Nanotubes for Data Processing Joerg Appenzeller, T. J. Watson Research Center, IBM Research.2 Electronic Structure of Graphene 4 2.3 Electronic Structure of Carbon Nanotubes 4 2.4 Transport Properties 6 2.5 Contacts 9 3 Synthesis of Carbon Nanotubes 10 3.1 Synthetic Methods 10 3.2 Growth Mechanisms 12

Joselevich, Ernesto

308

Raman spectroscopy of carbon nanotubes  

Microsoft Academic Search

The use of Raman spectroscopy to reveal the remarkable structure and the unusual electronic and phonon properties of single wall carbon nanotubes (SWNTs) is reviewed comprehensively. The various types of Raman scattering processes relevant to carbon nanotubes are reviewed, and the theoretical foundations for these topics are presented. The most common experimental techniques used to probe carbon nanotubes are summarized,

M. S. Dresselhaus; G. Dresselhaus; R. Saito; A. Jorio

2005-01-01

309

Raman Scattering in Carbon Nanotubes  

E-print Network

Raman Scattering in Carbon Nanotubes Ms.sc. Thesis Faculty of Science University of Copenhagen 2003;#12;Abstract The phonon properties of single-wall carbon nanotubes (SWNT's) are investi- gated using Raman. Employing a tight binding method the electronic structure of single-wall carbon nanotubes is explored the

Nygård, Jesper

310

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...

311

The Structures & Properties of Carbon  

ERIC Educational Resources Information Center

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…

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

2006-01-01

312

Full Carbon Account for Russia  

Microsoft Academic Search

The Forestry Project (FOR) at IIASA has produced a full carbon account (FCA) for Russia for 1990, together with scenarios for 2010. Currently, there are rather big question marks regarding the existing carbon accounts for Russia, and Russia is critical to the global carbon balance due to its size. IIASA is in a position to perform solid analysis of Russia

S. Nilsson; A. Shvidenko; V. Stolbovoi; M. Gluck; M. Jonas; M. Obersteiner

2000-01-01

313

Carbon Nanotube Linear Bearing Nanoswitches  

E-print Network

Carbon Nanotube Linear Bearing Nanoswitches V. V. Deshpande, H.-Y. Chiu, H. W. Ch. Postma, C. Miko-friction bearing capabilities of multiwalled carbon nanotubes (MWNTs) to realize nanoelectromechanical switches bearing capabilities3-5 of multi- and double-walled carbon nanotubes (MWNTs and DWNTs) to realize

Bockrath, Marc

314

Dispersion toughened silicon carbon ceramics  

DOEpatents

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.

Wei, G.C.

1984-01-01

315

Arnold Schwarzenegger THE CARBON DIOXIDE  

E-print Network

i Arnold Schwarzenegger Governor THE CARBON DIOXIDE ABATEMENT POTENTIAL OF CALIFORNIA'S MID, Afzal Siddiqui, and Judy Lai. 2011. The Carbon Dioxide Abatement Potential of California's Mid/Agricultural/Water EndUse Energy Efficiency · Renewable Energy Technologies · Transportation The Carbon Dioxide

316

8, 73157337, 2008 Carbon dioxide  

E-print Network

ACPD 8, 7315­7337, 2008 Carbon dioxide distributions over Europe C. Gurk et al. Title Page Abstract distributions of carbon dioxide over Europe C. Gurk1 , H. Fischer1 , P. Hoor1 , M.G. Lawrence1 , J. Lelieveld1 Publications on behalf of the European Geosciences Union. 7315 #12;ACPD 8, 7315­7337, 2008 Carbon dioxide

Paris-Sud XI, Université de

317

Getting to Know Global Carbon  

NSDL National Science Digital Library

GLOBE Carbon Cycle is focused on bringing the most cutting edge research and research techniques in the field of terrestrial ecosystem carbon cycling into the classroom. Students can collect data about their school field site through existing GLOBE protocols of phenology, land cover and soils as well as through new protocols focused on biomass and carbon stocks in vegetation.

2013-01-01

318

The geochemistry of late Archaean microbial carbonate: implications for ocean chemistry and continental erosion history  

Microsoft Academic Search

Trace element concentrations and combined Sr- and Nd-isotope compositions were determined on stromatolitic carbonates (microbialites) from the 2.52 Ga Campbellrand carbonate platform (South Africa). Shale-normalised rare earth element and yttrium patterns of the ancient samples are similar to those of modern seawater in having positive La and Y anomalies and in being depleted in light rare earth elements. In contrast

Balz S Kamber; Gregory E Webb

2001-01-01

319

Carbon sequestration and its role in the global carbon cycle  

USGS Publications Warehouse

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.

McPherson, Brian J.; Sundquist, Eric T.

2009-01-01

320

Carbon Sequestered, Carbon Displaced and the Kyoto Context  

SciTech Connect

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.

Marland, G.; Schlamadinger, B.

1999-04-18

321

Development of a carbon-carbon hip prosthesis.  

PubMed

This article deals with the use of carbon-fiber-reinforced-carbon materials for the manufacture of hip prosthesis stems. It considers the manufacturing process of carbon-carbon (C-C) composites made of carbon fibers infiltrated either with dense pyrolytic carbon or silicon carbide (SiC) through chemical vapor infiltration. The chemicophysical properties of these composites are examined according to their structures. The long-term response (2 years) of cortical bone to various types of carbon-carbon was evaluated mainly for bone contact and ingrowth. Carbon-carbon coated with calcium phosphate was found to speed up the bone formation as compared to pyrolytic carbon or SiC coatings. The low modulus of elasticity of the C-C materials could be responsible for quicker bone contact as compared to a much stiffer material like sintered aluminum oxide. The biomechanical performance of C-C hip stems was assessed through (a) implantations into cadaver femurs, (b) fatigue testing, and (c) finite element analysis. These tests showed: (a) a better stress transfer as compared to a metal prosthesis having the same design, (b) no fatigue damage, (c) a computerized stem stress distribution in accordance with the fractures obtained during static mechanical testing. PMID:3624286

Christel, P; Meunier, A; Leclercq, S; Bouquet, P; Buttazzoni, B

1987-08-01

322

Significant contribution of authigenic carbonate to marine carbon burial  

NASA Astrophysics Data System (ADS)

Carbon is removed from the Earth's surface through the formation and burial of carbon-bearing rocks and minerals. The formation of calcium carbonate and its burial in marine sediments accounts for around 80% of the total carbon removed from the Earth's surface. However, the fraction of calcium carbonate that precipitates in the oceans, versus that which precipitates authigenically in marine sediments, is unclear. Here, we compile measurements of the calcium concentration of pore fluids collected at 672 seafloor sites around the globe to calculate the global flux of calcium within marine sediments. We use these data, combined with alkalinity measurements of pore fluids, to quantify authigenic calcium carbonate precipitation. We estimate that the net calcium flux into marine sediments that can be ascribed to authigenic carbonate precipitation amounts to around 1×1012 mol yr-1. As such, we estimate that authigenic carbonate precipitation accounts for at least 10% of global carbonate accumulation. We show that much of the precipitation occurs along the eastern margins of ocean basins, where organic matter delivery to the sea floor is likely to be high. We suggest that authigenic calcium carbonate precipitation represents a non-negligible component of the global carbon cycle.

Sun, Xiaole; Turchyn, Alexandra V.

2014-03-01

323

Authigenic carbonate and the history of the global carbon cycle.  

PubMed

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. PMID:23372007

Schrag, Daniel P; Higgins, John A; Macdonald, Francis A; Johnston, David T

2013-02-01

324

Development of a carbon formation reactor for carbon dioxide reduction  

NASA Technical Reports Server (NTRS)

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.

Noyes, G.

1985-01-01

325

Erosion of soil organic carbon: implications for carbon sequestration  

USGS Publications Warehouse

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.

Van Oost, Kristof; Van Hemelryck, Hendrik; Harden, Jennifer W.

2009-01-01

326

The Global Carbon Cycle Radiative forcing  

E-print Network

The Global Carbon Cycle Radiative forcing Global carbon reservoirs Glacial-interglacial cycles Anthropogenic CO2 Ocean carbon cycle Carbonate chemistry and air-sea equilibrium "Solubility pump due to CO2 #12;Global carbon reservoirs #12;Geologic timescales #12;Pre-industrial Carbon Cycle

Follows, Mick

327

Integrating aquatic carbon fluxes in a boreal catchment carbon budget  

NASA Astrophysics Data System (ADS)

SummaryIn this paper, we assess the extent to which the export of terrestrially fixed carbon to aquatic systems and the aquatic metabolism of this carbon affect the overall accumulation of organic carbon in a boreal catchment. We estimated the contribution of stocks and processes in aquatic environments to the carbon balance of a boreal catchment in northern Sweden. We used published data concerning the net ecosystem exchange (NEE) of CO 2 in terrestrial environments, and calculations of loss of terrestrial carbon to surface water and the turnover of terrestrial carbon in aquatic systems. The NEE of terrestrial environments was estimated to be 139 g C/m 2 of catchment area per year. The export of terrestrially fixed carbon to aquatic systems was 8.6 g C/m 2/yr, resulting in a net accumulation of organic carbon in terrestrial systems of 131 g C/m 2/yr. Almost 45% of the terrestrial export was mineralized in streams and lakes and evaded as CO 2, while most of the remaining (approximately 55%) terrestrial export was transported to the sea as organic carbon or as dissolved inorganic carbon emanating from soil respiration. The sedimentation of organic carbon and input of organic carbon via aquatic primary production were insignificant when compared to the mineralization and river transport of terrestrial organic carbon. Aquatic fluxes were small compared to the terrestrial NEE, which we consider to be largely a consequence of the studied catchment being subject to intensive forestry resulting in a large annual accumulation of carbon in growing tree biomass.

Jonsson, A.; Algesten, G.; Bergström, A.-K.; Bishop, K.; Sobek, S.; Tranvik, L. J.; Jansson, M.

2007-02-01

328

Global carbon budget 2013  

NASA Astrophysics Data System (ADS)

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 data sets 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), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with 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 independent dynamic global vegetation models forced by observed climate, CO2 and land cover change (some including nitrogen-carbon interactions). All uncertainties are reported as ±1?, 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 0.9 ± 0.5 GtC yr-1, GATM 4.3 ± 0.1 GtC yr-1, SOCEAN 2.5 ± 0.5 GtC yr-1, and SLAND 2.8 ± 0.8 GtC yr-1. For year 2012 alone, EFF grew to 9.7 ± 0.5 GtC yr-1, 2.2% above 2011, reflecting a continued growing trend in these emissions, GATM was 5.1 ± 0.2 GtC yr-1, SOCEAN was 2.9 ± 0.5 GtC yr-1, and assuming an ELUC of 1.0 ± 0.5 GtC yr-1 (based on the 2001-2010 average), SLAND was 2.7 ± 0.9 GtC yr-1. GATM was high in 2012 compared to the 2003-2012 average, almost entirely reflecting the high EFF. The global atmospheric CO2 concentration reached 392.52 ± 0.10 ppm averaged over 2012. We estimate that EFF will increase by 2.1% (1.1-3.1%) to 9.9 ± 0.5 GtC in 2013, 61% above emissions in 1990, based on projections of world gross domestic product and recent changes in the carbon intensity of the economy. With this projection, cumulative emissions of CO2 will reach about 535 ± 55 GtC for 1870-2013, about 70% from EFF (390 ± 20 GtC) and 30% from ELUC (145 ± 50 GtC). This paper also documents any changes in the methods and data sets used in this new carbon budget from previous budgets (Le Quéré et al., 2013). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi:10.3334/CDIAC/GCP_2013_V2.3).

Le Quéré, C.; Peters, G. P.; Andres, R. J.; Andrew, R. M.; Boden, T. A.; 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.; Maignan, F.; 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.; Takahashi, T.; Tilbrook, B.; van Heuven, S.; Viovy, N.; Wanninkhof, R.; Wiltshire, A.; Zaehle, S.

2014-06-01

329

Carbon Capture and Storage, 2008  

ScienceCinema

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.

None

2010-01-08

330

Nanocrystalline diamond from carbon nanotubes  

NASA Astrophysics Data System (ADS)

Structural phase transformation from multiwalled carbon nanotubes to nanocrystalline diamond by hydrogen plasma post-treatment was carried out. Ultrahigh equivalent diamond nucleation density above 1011 nuclei/cm2 was easily obtained. The diamond formation and growth mechanism was proposed to be the consequence of the formation of sp3 bonded amorphous carbon clusters. The hydrogen chemisorption on curved graphite network and the energy deposited on the carbon nanotubes by continuous impingement of activated molecular or atomic hydrogen are responsible for the formation of amorphous carbon matrix. Diamond nucleates and grows in the way similar to that of diamond chemical vapor deposition processes on amorphous carbon films.

Sun, L. T.; Gong, J. L.; Zhu, Z. Y.; Zhu, D. Z.; He, S. X.; Wang, Z. X.; Chen, Y.; Hu, G.

2004-04-01

331

Carbon Capture and Storage, 2008  

SciTech Connect

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.

2009-03-19

332

Understanding the Global Carbon Cycle  

NSDL National Science Digital Library

The site offers charts and graphs to aid in a detailed explanation of where carbon comes from and where it goes. Supplementing the main topic, links lead to the topics Carbon and Land Use, Missing Carbon Sink, and Forest Sequestered Carbon Dioxide. Their conclusion is that the major contributor to climatic change, and hence the human activity most in need of change, is use of fossil fuels for energy. Advances in the technology of renewable energy sources, including wood-derived fuels, might reduce our reliance on fossil fuels and thus reduce global emissions of carbon dioxide significantly.

333

Carbon dioxide dangers demonstration model  

USGS Publications Warehouse

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.

Venezky, Dina; Wessells, Stephen

2010-01-01

334

DETERMINATION OF OXYGEN IN YTTRIUM FLUORIDE BY A VACUUM DISTILLATION TECHNIQUE  

Microsoft Academic Search

A conventional vacuum fusion gas analysis unit is used for the ; determination of oxygen in yttrium fluoride. The yttrium fluoride ia distilled ; from the furnace, leaving the less volatile oxygen-containing compounds to be ; reduced by the carbon crucible. Recoveries of oxygen are quantitative when a ; liquid reaction medium is provided for the reduction. The effect of

V. M. Horrigan; V. A. Fassel; J. W. Goetzinger

1960-01-01

335

Raman Spectroscopy of Amorphous Carbon  

SciTech Connect

Amorphous carbon is an elemental form of carbon with low hydrogen content, which may be deposited in thin films by the impact of high energy carbon atoms or ions. It is structurally distinct from the more well-known elemental forms of carbon, diamond and graphite. It is distinct in physical and chemical properties from the material known as diamond-like carbon, a form which is also amorphous but which has a higher hydrogen content, typically near 40 atomic percent. Amorphous carbon also has distinctive Raman spectra, whose patterns depend, through resonance enhancement effects, not only on deposition conditions but also on the wavelength selected for Raman excitation. This paper provides an overview of the Raman spectroscopy of amorphous carbon and describes how Raman spectral patterns correlate to film deposition conditions, physical properties and molecular level structure.

Tallant, D.R.; Friedmann, T.A.; Missert, N.A.; Siegal, M.P.; Sullivan, J.P.

1998-01-01

336

Carbon Fiber Composites  

NASA Technical Reports Server (NTRS)

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.

1997-01-01

337

Depositing Diamondlike Carbon Films  

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

338

Carbon Dioxide Landscape  

NASA Technical Reports Server (NTRS)

23 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of some of the widely-varied terrain of the martian south polar residual cap. The landforms here are composed mainly of frozen carbon dioxide. Each year since MGS arrived in 1997, the scarps that bound each butte and mesa, or line the edges of each pit, in the south polar region, have changed a little bit as carbon dioxide is sublimed away. The scarps retreat at a rate of about 3 meters (3 yards) per martian year. Most of the change occurs during each southern summer.

Location near: 86.7oS, 9.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

2005-01-01

339

EB2012-MS-43 ADVANCES IN THE MODELLING OF CARBON/CARBON  

E-print Network

EB2012-MS-43 ADVANCES IN THE MODELLING OF CARBON/CARBON COMPOSITE UNDER TRIBOLOGICAL CONSTRAINTS 1, homogenization, carbon ABSTRACT Thermo mechanical properties of Carbon-Carbon composite (C/C) allow them, the Carbon-Carbon composites (C/C) are materials frequently used in industrial applications such as plane

Paris-Sud XI, Université de

340

Carbon K-edge Spectra of Carbonate Minerals  

SciTech Connect

Carbon K-edge X-ray spectroscopy has been applied to the study of a wide range of organic samples, from polymers and coals to interstellar dust particles. Identification of carbonaceous materials within these samples is accomplished by the pattern of resonances in the 280-320 eV energy region. Carbonate minerals are often encountered in the study of natural samples, and have been identified by a distinctive resonance at 290.3 eV. Here C K-edge and Ca L-edge spectra from a range of carbonate minerals are presented. Although all carbonates exhibit a sharp 290 eV resonance, both the precise position of this resonance and the positions of other resonances vary among minerals. The relative strengths of the different carbonate resonances also vary with crystal orientation to the linearly polarized X-ray beam. Intriguingly, several carbonate minerals also exhibit a strong 288.6 eV resonance, consistent with the position of a carbonyl resonance rather than carbonate. Calcite and aragonite, although indistinguishable spectrally at the C K-edge, exhibited significantly different spectra at the Ca L-edge. The distinctive spectral fingerprints of carbonates provide an identification tool, allowing for the examination of such processes as carbon sequestration in minerals, Mn substitution in marine calcium carbonates (dolomitization) and serpentinization of basalts.

Brandes, J.; Wirick, S; Jacobsen, C

2010-01-01

341

Quantitative analysis of carbon in silicon carbide coated with carbon.  

PubMed

Nonconductive specimens for scanning electron microscopy or X-ray microanalysis are coated with conductive carbon in order to reduce charging. But carbon film absorbs X-ray fluxes causing errors in measuring chemical composition. Especially when the carbon content is measured, carbon coating not only blocks X-rays but also becomes a source of carbon X-rays. It is thus necessary to determine how much errors are induced by carbon coating, and how thick coating is allowed for the accurate measurement. In this study, quantitative analysis of carbon on silicon carbide with carbon coating films was attempted by electron probe microanalyzer. It was found that measured carbon content increased in a nonlinear manner up to 40% with a film thickness, whereas silicon content decreased slightly. Carbon X-ray intensity was determined by computer simulation, which increased in a linear manner with the thickness. The discrepancy was due to a nucleation and growth of islands and thus a change of density with a thickening of coating film. PMID:23920162

Lee, Hongrim; Kim, Junsu; Yun, Jondo

2013-08-01

342

Carbon nanotube network varactor  

NASA Astrophysics Data System (ADS)

Microelectromechanical system (MEMS) varactors based on a freestanding layer of single-walled carbon nanotube (SWCNT) films were designed, fabricated and tested. The freestanding SWCNT film was employed as a movable upper patch in the parallel plate capacitor of the MEMS. The measurements of the SWCNT varactors show very high tunability, nearly 100%, of the capacitance with a low actuation voltage of 10 V. The functionality of the varactor is improved by implementing a flexible nanocellulose aerogel filling.

Generalov, A. A.; Anoshkin, I. V.; Erdmanis, M.; Lioubtchenko, D. V.; Ovchinnikov, V.; Nasibulin, A. G.; Räisänen, A. V.

2015-01-01

343

Carbon nanotube network varactor.  

PubMed

Microelectromechanical system (MEMS) varactors based on a freestanding layer of single-walled carbon nanotube (SWCNT) films were designed, fabricated and tested. The freestanding SWCNT film was employed as a movable upper patch in the parallel plate capacitor of the MEMS. The measurements of the SWCNT varactors show very high tunability, nearly 100%, of the capacitance with a low actuation voltage of 10 V. The functionality of the varactor is improved by implementing a flexible nanocellulose aerogel filling. PMID:25556375

Generalov, A A; Anoshkin, I V; Erdmanis, M; Lioubtchenko, D V; Ovchinnikov, V; Nasibulin, A G; Räisänen, A V

2015-01-30

344

CARBON DIOXIDE FIXATION.  

SciTech Connect

Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

FUJITA,E.

2000-01-12

345

Amorphous Carbon Nanospheres  

SciTech Connect

Amorphous carbon nanosphere used as the anode material for Li-intercalation in Lithium-ion energy storage. This structure was obtained through a thermal annealing process at a temperature of 3000 degree Kelvin, simulated using the LAMMPS molecular dynamics code on the LCRC Fusion resource. Science: Kah Chun Lau, Larry Curtiss, Argonne National Laboratory Visualization: Aaron Knoll, Mark Hereld, Michael E. Papka, Argonne National Laboratory

None

2012-01-01

346

Assessing geochemical carbon management  

Microsoft Academic Search

The challenge of reversing rising atmospheric CO2 concentrations is growing with the continued expansion of CO2-emitting energy infrastructure throughout the world and with the lack of coordinated, effective measures to manage and reduce\\u000a emissions. Given this situation, it is prudent for society to explore all potential carbon management options, including those\\u000a with seemingly low probability for success. Recent initiatives for

Jennie C. Stephens; David W. Keith

2008-01-01

347

Carbonate fuel cell matrix  

DOEpatents

A carbonate fuel cell matrix comprising support particles and crack attenuator particles which are made platelet in shape to increase the resistance of the matrix to through cracking. Also disclosed is a matrix having porous crack attenuator particles and a matrix whose crack attenuator particles have a thermal coefficient of expansion which is significantly different from that of the support particles, and a method of making platelet-shaped crack attenuator particles.

Farooque, Mohammad (Huntington, CT); Yuh, Chao-Yi (New Milford, CT)

1996-01-01

348

The Carbon Cycle  

NSDL National Science Digital Library

This online lab exercise focuses on the processes involved in the Carbon cycle and the influences of human activity on those processes- especially as they relate to Earth's weather and climate. The fourth in a 10-part lab series on weather and climate, this lab exercise is designed for first and second year college geoscience students (majors and non-majors) as well as pre-service STEM teachers.

349

Total organic carbon analyzer  

Microsoft Academic Search

The development and testing of a breadboard version of a highly sensitive total-organic-carbon (TOC) analyzer are reported. Attention is given to the system components including the CO2 sensor, oxidation reactor, acidification module, and the sample-inlet system. Research is reported for an experimental reagentless oxidation reactor, and good results are reported for linearity, sensitivity, and selectivity in the CO2 sensor. The

Richard G. Godec; Paul P. Kosenka; Brian D. Smith; Richard S. Hutte; Johanna V. Webb; Richard L. Sauer

1991-01-01

350

Low dimensional carbon electronics  

NASA Astrophysics Data System (ADS)

This thesis covers several different experiments that comprised my graduate career. The main focus of these experiments was the use of carbon as an electronic material and a steady evolution of fabrication recipes that allowed us to perform reliable and consistent measurements. The second chapter describes experiments with carbon nanotubes, where our goal was to produce devices capable of manipulating electronic spin states in order create quantum bits or "qubits." The third chapter covers the development of fabrication recipes with the goal of creating qubits within Si-Ge nanowire, and the bottom-gating approach that was developed. The fourth chapter begins graphene related research, describing one of the simplest uses of graphene as a simple transparent electrode on a SiN micromembrane. The remainder of the thesis describes experiments that develop graphene based optical and infrared detectors, study their characteristics and determine the physics that underlies their detection mechanism. Key in these experiments were the fabrication recipes that had been developed to create carbon nanotube and Si-Ge nanowire devices. Finally, we demonstrate how engineering of the device's thermal characteristics can lead to improved sensitivity and how graphene can be used in novel applications where conventional materials are not suitable.

Herring, Patrick Kenichi

351

Frozen Carbon Dioxide  

NASA Technical Reports Server (NTRS)

1 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a south polar residual cap landscape, formed in frozen carbon dioxide. There is no place on Earth that one can go to visit a landscape covering thousands of square kilometers with frozen carbon dioxide, so mesas, pits, and other landforms of the martian south polar region are as alien as they are beautiful. The scarps of the south polar region are known from thousands of other MGS MOC images to retreat at a rate of about 3 meters (3 yards) per martian year, indiating that slowly, over the course of the MGS mission, the amount of carbon dioxide in the martian atmosphere has probably been increasing.

Location near: 86.9oS, 25.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

2005-01-01

352

Carbon Dioxide Landforms  

NASA Technical Reports Server (NTRS)

19 March 2004 The martian south polar residual ice cap is mostly made of frozen carbon dioxide. There is no place on Earth that a person can go to see the landforms that would be produced by erosion and sublimation of hundreds or thousands of cubic kilometers of carbon dioxide. Thus, the south polar cap of Mars is as alien as alien can get. This image, acquired in February 2004 by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), shows how the cap appears in summer as carbon dioxide is subliming away, creating a wild pattern of pits, mesas, and buttes. Darker surfaces may be areas where the ice contains impurities, such as dust, or where the surface has been roughened by the removal of ice. This image is located near 86.3oS, 0.8oW. This picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the top/upper left.

2004-01-01

353

Carbon taxes and India  

SciTech Connect

Using the Indian module of the Second Generation Model 9SGM, we explore a reference case and three scenarios in which greenhouse gas emissions were controlled. Two alternative policy instruments (carbon taxes and tradable permits) were analyzed to determine comparative costs of stabilizing emissions at (1) 1990 levels (the 1 X case), (2) two times the 1990 levels (the 2X case), and (3) three times the 1990 levels (the 3X case). The analysis takes into account India`s rapidly growing population and the abundance of coal and biomass relative to other fuels. We also explore the impacts of a global tradable permits market to stabilize global carbon emissions on the Indian economy under the following two emissions allowance allocation methods: (1) {open_quotes}Grandfathered emissions{close_quotes}: emissions allowances are allocated based on 1990 emissions. (2) {open_quotes}Equal per capita emissions{close_quotes}: emissions allowances are allocated based on share of global population. Tradable permits represent a lower cost method to stabilize Indian emissions than carbon taxes, i.e., global action would benefit India more than independent actions.

Fisher-Vanden, K.A.; Pitcher, H.M.; Edmonds, J.A.; Kim, S.H. [Pacific Northwest Lab., Richland, WA (United States); Shukla, P.R. [Indian Institute of Management, Ahmedabad (India)

1994-07-01

354

Studies of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

The fellowship experience for this summer for 2004 pertains to carbon nanotube coatings for various space-related applications. They involve the following projects: (a) EMI protection films from HiPco-polymers, and (b) Thermal protection nanosilica materials. EMI protection films are targeted to be eventually applied onto casings of laptop computers. These coatings are composites of electrically-conductive SWNTs and compatible polymers. The substrate polymer will be polycarbonate, since computer housings are typically made of carbon composites of this type of polymer. A new experimental copolymer was used last year to generate electrically-conductive and thermal films with HiPco at 50/50 wt/wt composition. This will be one of the possible formulations. Reference films will be base polycarbonate and neat HiPco onto polycarbonate films. Other coating materials that will be tried will be based on HiPco composites with commercial enamels (polyurethane, acrylic, polyester), which could be compatible with the polycarbonate substrate. Nanosilica fibers are planned for possible use as thermal protection tiles on the shuttle orbiter. Right now, microscale silica is used. Going to the nanoscale will increase the surface-volume-per-unit-area of radiative heat dissipation. Nanoscale carbon fibers/nanotubes can be used as templates for the generation of nanosilica. A sol-gel operation is employed for this purpose.

Caneba, Gerard T.

2005-01-01

355

Thermal Cycling of Thermal Control Paints on Carbon-Carbon and Carbon-Polyimide Composites  

NASA Technical Reports Server (NTRS)

Carbon-carbon composites and carbon-polyimide composites are being considered for space radiator applications owing to their light weight and high thermal conductivity. For those radiator applications where sunlight will impinge on the surface, it will be necessary to apply a white thermal control paint to minimize solar absorptance and enhance infrared emittance. Several currently available white thermal control paints were applied to candidate carbon-carbon and carbon-polyimide composites and were subjected to vacuum thermal cycling in the range of -100 C to +277 C. The optical properties of solar absorptance and infrared emittance were evaluated before and after thermal cycling. In addition, adhesion of the paints was evaluated utilizing a tape test. The test matrix included three composites: resin-derived carbon-carbon and vapor infiltrated carbon-carbon, both reinforced with pitch-based P-120 graphite fibers, and a polyimide composite reinforced with T-650 carbon fibers, and three commercially available white thermal control paints: AZ-93, Z-93-C55, and YB-71P.

Jaworske, Donald A.

2006-01-01

356

Oxidative Attack of Carbon/Carbon Substrates through Coating Pinholes  

NASA Technical Reports Server (NTRS)

A critical issue with oxidation protected carbon/carbon composites used for spacecraft thermal protection is the formation of coating pinholes. In laboratory experiments, artificial pinholes were drilled through SiC-coatings on a carbon/carbon material and the material was oxidized at 600, 1000, and 1400 C at reduced pressures of air. The attack of the carbon/carbon was quantified by both weight loss and a novel cross-sectioning technique. A two-zone, one dimensional diffusion control model was adapted to analyze this problem. Agreement of the model with experiment was reasonable at 1000 and 1400 C; however results at lower temperatures show clear deviations from the theory suggesting that surface reaction control plays a role.

Jacobson, Nathan S.; Leonhardt, Todd; Curry, Donald; Rapp, Robert A.

1998-01-01

357

Implications of carbon dust emission for terrestrial carbon cycling and carbon accounting  

NASA Astrophysics Data System (ADS)

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, or within national carbon accounting schemes. Current estimates of the loss of SOC to wind erosion do not consider the preferential removal and enrichment of SOC in dust emissions, and consequently underestimate the significance of carbon dust emissions for the carbon cycle and carbon accounting. We present a process-based approximation of SOC enrichment within the Computational Environmental Management System (CEMSYS v5) Australian national wind erosion model. It enabled the prediction of carbon dust emission at a 50 km spatial resolution across Australia each month from 2000-2011. Our results show that the total dust emission for Australia is 118 Mt yr-1, with carbon dust emissions (<22 ?m) in the order of 1.59 Mt yr-1. Rangelands are found to produce ~84% of Australia's carbon dust emissions (1.34 Mt yr-1), while agricultural lands produce 0.11 Mt yr-1. However, agricultural lands produce larger carbon dust emissions per km2 than rangelands. The long-distance transport of SOC by wind is expected to result in large mineralisation rates due to (e.g.) photochemical oxidation, and the release of up to 5.9 Mt CO2-e yr-1. These results on the loss of SOC in dust, and the release of CO2 during long-distance transport, demonstrate the need for aeolian processes to be given greater significance in terrestrial carbon cycling, and for them to be incorporated into carbon accounting systems.

Webb, N.; Chappell, A.; Butler, H.; Strong, C.; McTainsh, G.; Leys, J.

2012-12-01

358

The Toxicology of Carbon Nanotubes  

NASA Astrophysics Data System (ADS)

1. Carbon nanotube structure, synthesis and applications C. Singh and W. Song; 2. The aerodynamic behaviour and pulmonary deposition of carbon nanotubes A. Buckley, R. Smith and R Maynard; 3. Utilising the concept of the biologically effective dose to define the particle and fibre hazards of carbon nanotubes K. Donaldson, R. Duffin, F. Murphy and C. Poland; 4. CNT, biopersistence and the fibre paradigm D. Warheit and M. DeLorme; 5. Length-dependent retention of fibres in the pleural space C. Poland, F. Murphy and K. Donaldson; 6. Experimental carcinogenicity of carbon nanotubes in the context of other fibres K. Unfried; 7. Fate and effects of carbon nanotubes following inhalation J. Ryman-Rasmussen, M. Andersen and J. Bonner; 8. Responses to pulmonary exposure to carbon nanotubes V. Castranova and R. Mercer; 9. Genotoxicity of carbon nanotubes R. Schins, C. Albrecht, K. Gerloff and D. van Berlo; 10. Carbon nanotube-cellular interactions; macrophages, epithelial and mesothelial cells V. Stone, M. Boyles, A. Kermanizadeh, J. Varet and H. Johnston; 11. Systemic health effects of carbon nanotubes following inhalation J. McDonald; 12. Dosimetry and metrology of carbon nanotubes L. Tran, L. MacCalman and R. Aitken; Index.

Donaldson, Ken; Poland, Craig; Duffin, Rodger; Bonner, James

2012-06-01

359

Uncovering the Neoproterozoic carbon cycle.  

PubMed

Interpretations of major climatic and biological events in Earth history are, in large part, derived from the stable carbon isotope records of carbonate rocks and sedimentary organic matter. Neoproterozoic carbonate records contain unusual and large negative isotopic anomalies within long periods (10-100 million years) characterized by ?(13)C in carbonate (?(13)C(carb)) enriched to more than +5 per mil. Classically, ?(13)C(carb) is interpreted as a metric of the relative fraction of carbon buried as organic matter in marine sediments, which can be linked to oxygen accumulation through the stoichiometry of primary production. If a change in the isotopic composition of marine dissolved inorganic carbon is responsible for these excursions, it is expected that records of ?(13)C(carb) and ?(13)C in organic carbon (?(13)C(org)) will covary, offset by the fractionation imparted by primary production. The documentation of several Neoproterozoic ?(13)C(carb) excursions that are decoupled from ?(13)C(org), however, indicates that other mechanisms may account for these excursions. Here we present ?(13)C data from Mongolia, northwest Canada and Namibia that capture multiple large-amplitude (over 10 per mil) negative carbon isotope anomalies, and use these data in a new quantitative mixing model to examine the behaviour of the Neoproterozoic carbon cycle. We find that carbonate and organic carbon isotope data from Mongolia and Canada are tightly coupled through multiple ?(13)C(carb) excursions, quantitatively ruling out previously suggested alternative explanations, such as diagenesis or the presence and terminal oxidation of a large marine dissolved organic carbon reservoir. Our data from Namibia, which do not record isotopic covariance, can be explained by simple mixing with a detrital flux of organic matter. We thus interpret ?(13)C(carb) anomalies as recording a primary perturbation to the surface carbon cycle. This interpretation requires the revisiting of models linking drastic isotope excursions to deep ocean oxygenation and the opening of environments capable of supporting animals. PMID:22388817

Johnston, D T; Macdonald, F A; Gill, B C; Hoffman, P F; Schrag, D P

2012-03-15

360

Geologic Carbon Sequestration and Biosequestration (Carbon Cycle 2.0)  

SciTech Connect

Don DePaolo, Director of LBNL's Earth Sciences Division, 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/

DePaolo, Don [Director, LBNL Earth Sciences Division] [Director, LBNL Earth Sciences Division

2010-02-03

361

Method for joining carbon-carbon composites to metals  

DOEpatents

A method for joining carbon-carbon composites to metals by brazing. Conventional brazing of recently developed carbon-bonded carbon fiber (CBCF) material to a metal substrate is limited by the tendency of the braze alloy to "wick" into the CBCF composite rather than to form a strong bond. The surface of the CBCF composite that is to be bonded is first sealed with a fairly dense carbonaceous layer achieved by any of several methods. The sealed surface is then brazed to the metal substrate by vacuum brazing with a Ti-Cu-Be alloy.

Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Moorhead, Arthur J. (Knoxville, TN)

1997-01-01

362

Geologic Carbon Sequestration and Biosequestration (Carbon Cycle 2.0)  

ScienceCinema

Don DePaolo, Director of LBNL's Earth Sciences Division, 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/

DePaolo, Don [Director, LBNL Earth Sciences Division

2011-06-08

363

Soil warming, carbon-nitrogen interactions, and forest carbon budgets.  

PubMed

Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon-nitrogen interactions in atmosphere-ocean-land earth system models to accurately simulate land feedbacks to the climate system. PMID:21606374

Melillo, Jerry M; Butler, Sarah; Johnson, Jennifer; Mohan, Jacqueline; Steudler, Paul; Lux, Heidi; Burrows, Elizabeth; Bowles, Francis; Smith, Rose; Scott, Lindsay; Vario, Chelsea; Hill, Troy; Burton, Andrew; Zhou, Yu-Mei; Tang, Jim

2011-06-01

364

Soil warming, carbon–nitrogen interactions, and forest carbon budgets  

PubMed Central

Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon–nitrogen interactions in atmosphere–ocean–land earth system models to accurately simulate land feedbacks to the climate system. PMID:21606374

Melillo, Jerry M.; Butler, Sarah; Johnson, Jennifer; Mohan, Jacqueline; Steudler, Paul; Lux, Heidi; Burrows, Elizabeth; Bowles, Francis; Smith, Rose; Scott, Lindsay; Vario, Chelsea; Hill, Troy; Burton, Andrew; Zhou, Yu-Mei; Tang, Jim

2011-01-01

365

Carbon-Carbon Turbocharger Housing Unit for Intermittent Combustion Engines  

NASA Technical Reports Server (NTRS)

An improved, lightweight, turbine housing unit for an intermittent combustion reciprocating internal combustion engine turbocharger is prepared from a lay-up or molding of carbon-carbon composite materials in a single-piece or two-piece process. When compared to conventional steel or cast iron, the use of carbon-carbon composite materials in a turbine housing unit reduces the overall weight of the engine and reduces the heat energy loss used in the turbocharging process. This reduction in heat energy loss and weight reduction provides for more efficient engine operation.

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

1998-01-01

366

Carbon Emission Flow in Networks  

PubMed Central

As the human population increases and production expands, energy demand and anthropogenic carbon emission rates have been growing rapidly, and the need to decrease carbon emission levels has drawn increasing attention. The link between energy production and consumption has required the large-scale transport of energy within energy transmission networks. Within this energy flow, there is a virtual circulation of carbon emissions. To understand this circulation and account for the relationship between energy consumption and carbon emissions, this paper introduces the concept of “carbon emission flow in networks” and establishes a method to calculate carbon emission flow in networks. Using an actual analysis of China's energy pattern, the authors discuss the significance of this new concept, not only as a feasible approach but also as an innovative theoretical perspective. PMID:22761988

Kang, Chongqing; Zhou, Tianrui; Chen, Qixin; Xu, Qianyao; Xia, Qing; Ji, Zhen

2012-01-01

367

Self-organized carbon nanotips  

NASA Astrophysics Data System (ADS)

We have developed a carbon nanostructure, which is comprised of high-density carbon nanotips on a graphite layer. These carbon nanotips, with tip diameters of ˜10 nm, are grown by high-density plasma chemical vapor deposition onto Ni-coated Si using an inductively coupled plasma. The Ni on Si changes into NiSi2 by substrate heating. First, a carbon buffer layer and then a graphene sheet are formed on the NiSi2. Then, the carbon nanotips are grown by a C2H2/H2 plasma on the graphene sheet. The carbon nanotips show good adhesion to the substrate and are almost aligned, with an average length of 110 nm. They exhibit a turn-on field of 0.1 V/?m, a field amplification factor of ˜13 000, a current density of 2 mA/cm2 at a field of 2 V/?m, and uniform electron emission.

Jang, Jin; Chung, Suk Jae; Kim, Hong Sik; Lim, Sung Hoon; Lee, Choong Hun

2001-09-01

368

Radiocarbon dating of terrestrial carbonates  

USGS Publications Warehouse

Terrestrial carbonates encompass a wide range of materials that potentially could be used for radiocarbon (14C) dating. Biogenic carbonates, including shells and tests of terrestrial and aquatic gastropods, bivalves, ostracodes, and foraminifera, are preserved in a variety of late Quaternary deposits and may be suitable for 14C dating. Primary calcareous deposits (marls, tufa, speleothems) and secondary carbonates (rhizoliths, fracture fill, soil carbonate) may also be targeted for dating when conditions are favorable. This chapter discusses issues that are commonly encountered in 14C dating of terrestrial carbonates, including isotopic disequilibrium and open-system behavior, as well as methods used to determine the reliability of ages derived from these materials. Recent methodological advancements that may improve the accuracy and precision of 14C ages of terrestrial carbonates are also highlighted.

Pigati, Jeffrey S.

2014-01-01

369

Compilation of carbon-14 data  

SciTech Connect

A review and critical analysis was made of the original sources of carbon-14 in the graphite moderator and reflector zones of the eight Hanford production reactors, the present physical and chemical state of the carbon-14, pathways (other than direct combustion) by which the carbon-14 could be released to the biosphere, and the maximum rate at which it might be released under circumstances which idealistically favor the release. Areas of uncertainty are noted and recommendations are made for obtaining additional data in three areas: (1) release rate of carbon-14 from irradiated graphite saturated with aerated water; (2) characterization of carbon-14 deposited outside the moderator and reflector zones; and (3) corrosion/release rate of carbon-14 from irradiated steel and aluminum alloys.

Paasch, R.A.

1985-07-08

370

Howell, R.A., 2012 Living with a carbon allowance 1 Living with a carbon allowance: the experiences of Carbon  

E-print Network

Howell, R.A., 2012 Living with a carbon allowance 1 Living with a carbon allowance: the experiences of Carbon Rationing Action Groups and implications for policy Rachel A. Howell Environmental Change with a carbon allowance: the experiences of Carbon Rationing Action Groups and implications for policy. Energy

371

Carbon uptake in low dissolved inorganic carbon environments: the effect of limited carbon availability on photosynthetic organisms in thermal waters  

Microsoft Academic Search

Photosynthesis is the primary carbon fixation process in thermal waters below 70°C, but some hydrothermal waters have extremely low dissolved inorganic carbon (DIC), potentially limiting the growth of inorganic carbon fixing organisms such as algae and cyanobacteria. To address the issue of how carbon is assimilated by phototrophs in these environments, we conducted experiments to compare inorganic carbon uptake mechanisms

K. D. Myers; C. R. Omelon; P. Bennett

2010-01-01

372

Alternative cathodes for molten carbonate fuel cells  

SciTech Connect

Yttrium Ions Garnets (YIG), Y{sub 3}Fe{sub 5}O{sub 12}, and Barium Ferrite, BaFe{sub 12}O{sub 19}, were synthesized and characterized. Among the various synthesis techniques tried the gel resin process was found to be the best method of synthesis in terms of purity of the phase and the conventional powder mixing/calcination technique was found to give the highest yield of the desired phase in larger quantities. Doping and calcining conditions were established to synthesize phase pure Ca-doped cubic YIG. The weight loss of doped YIG in molten carbonate was comparable to that reported for NiO, the current state-of-the-art cathode material. However, the stability of the YIG is expected to be better than NiO due to the stability of the corrosion product, Y{sub 2}O{sub 3}. The performance of doped YIG cathode in an in-cell test at the Institute of Gas Technology was below the present state of the are cathode due to high polarization loss. A Barium Ferrite based magnetoplumbite material was tested as a potential cathode candidate in molten carbonate. The material formed a reaction product that was conductive at room temperature; it also exhibited some magnetization.

Rolfson, B.K.; Elangovan, S.; Khandkar, A.C. (Ceramatec, Inc., Salt Lake City, UT (USA))

1990-05-01

373

Carbon dioxide affects global ecology  

Microsoft Academic Search

Man's activities are changing the carbon dioxide and oxygen content of the entire atmosphere. These changes may, in turn, affect worldwide weather and the growth of plants. Under normal conditions, the amounts of carbon dioxide and oxygen in the atmosphere remain approximately in equilibrium on a year-to-year basis. The atmosphere today contains about 21% oxygen and about 0.032% carbon dioxide

Eugene K. Peterson

1969-01-01

374

Lithium Diffusion in Graphitic Carbon  

Microsoft Academic Search

Graphitic carbon is currently considered the state-of-the-art material for the negative electrode in lithium-ion cells, mainly due to its high reversibility and low operating potential. However, carbon anodes exhibit mediocre charge\\/discharge rate performance, which contributes to severe transport-induced surface-structural damage upon prolonged cycling, and limits the lifetime of the cell. Lithium bulk diffusion in graphitic carbon is not yet completely

Kristin Persson; Vijay A. Sethuraman; Laurence J. Hardwick; Yoyo Hinuma; Ying Shirley Meng; Anton van der Ven; Venkat Srinivasan; Robert Kostecki; Gerbrand Ceder

2011-01-01

375

What is the Carbon Cycle?  

NSDL National Science Digital Library

This activity has students explore the carbon cycle and learn to identify carbon sources, sinks, and release agents. They will come to understand that carbon is critical to the biosphere and must continue cycling to support life on earth. The instructor guide contains detailed background material, learning goals, alignment to national standards, grade level/time, details on materials and preparation, procedure, assessment ideas, and modifications for alternative learners.

376

Carbon Dioxide Production at Home  

NSDL National Science Digital Library

In this problem set, learners will consider the "Carbon Footprint" of a family of four in a given context, as well as the US and global averages, and compare that with their own to answer a series of questions. They will use an online Carbon Footprint calculator to determine their own per-capita carbon production. Answer key is provided. This problem is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

2012-08-03

377

Doped nanocrystalline calcium carbonate phosphates  

Microsoft Academic Search

The formation of nanocrystalline calcium carbonate phosphates doped with Fe2+, Mg2, Zn2+, K+, Si4+, and Mn2+ has been studied by X-ray diffraction, IR spectroscopy, differential thermal analysis, and energy dispersive X-ray fluorescence\\u000a analysis. The results indicate that the synthesis involves the formation of hydroxy carbonate complexes from the three calcium\\u000a carbonate polymorphs (calcite, vaterite, and aragonite) in a solution of

L. F. Koroleva

2010-01-01

378

Global carbon budget 2014  

NASA Astrophysics Data System (ADS)

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 and cement production data, respectively, while emissions from Land-Use Change (ELUC), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with 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 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 independent Dynamic Global Vegetation Models forced by observed climate, CO2 and land cover change (some including nitrogen-carbon interactions). We compare the variability and mean land and ocean fluxes to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as ±1?, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2004-2013), EFF was 8.9 ± 0.4 GtC yr-1, ELUC 0.9 ± 0.5 GtC yr-1, GATM 4.3 ± 0.1 GtC yr-1, SOCEAN 2.6 ± 0.5 GtC yr-1, and SLAND 2.9 ± 0.8 GtC yr-1. For year 2013 alone, EFF grew to 9.9 ± 0.5 GtC yr-1, 2.3% above 2012, contining the growth trend in these emissions. ELUC was 0.9 ± 0.5 GtC yr-1, GATM was 5.4 ± 0.2 GtC yr-1, SOCEAN was 2.9 ± 0.5 GtC yr-1 and SLAND was 2.5 ± 0.9 GtC yr-1. GATM was high in 2013 reflecting a steady increase in EFF and smaller and opposite changes between SOCEAN and SLAND compared to the past decade (2004-2013). The global atmospheric CO2 concentration reached 395.31 ± 0.10 ppm averaged over 2013. We estimate that EFF will increase by 2.5% (1.3-3.5%) to 10.1 ± 0.6 GtC in 2014 (37.0 ± 2.2 GtCO2 yr-1), 65% above emissions in 1990, based on projections of World Gross Domestic Product and recent changes in the carbon intensity of the economy. From this projection of EFF and assumed constant ELUC for 2014, cumulative emissions of CO2 will reach about 545 ± 55 GtC (2000 ± 200 GtCO2) for 1870-2014, about 75% from EFF and 25% from ELUC. This paper documents changes in the methods and datasets used in this new carbon budget compared with previous publications of this living dataset (Le Quéré et al., 2013, 2014). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi:10.3334/CDIAC/GCP_2014). Italic font highlights significant methodological changes and results compared to the Le Quéré et al. (2014) manuscript that accompanies the previous version of this living data.

Le Quéré, C.; Moriarty, R.; Andrew, R. M.; Peters, G. P.; Ciais, P.; Friedlingstein, P.; Jones, S. D.; Sitch, S.; Tans, P.; Arneth, A.; Boden, T. A.; Bopp, L.; Bozec, Y.; Canadell, J. G.; Chevallier, F.; Cosca, C. E.; Harris, I.; Hoppema, M.; Houghton, R. A.; House, J. I.; Jain, A.; Johannessen, T.; Kato, E.; Keeling, R. F.; Kitidis, V.; Klein Goldewijk, K.; Koven, C.; Landa, C. S.; Landschützer, P.; Lenton, A.; Lima, I. D.; Marland, G.; Mathis, J. T.; Metzl, N.; Nojiri, Y.; Olsen, A.; Ono, T.; Peters, W.; Pfeil, B.; Poulter, B.; Raupach, M. R.; Regnier, P.; Rödenbeck, C.; Saito, S.; Salisbury, J. E.; Schuster, U.; Schwinger, J.; Séférian, R.; Segschneider, J.; Steinhoff, T.; Stocker, B. D.; Sutton, A. J.; Takahashi, T.; Tilbrook, B.; van der Werf, G. R.; Viovy, N.; Wang, Y.-P.; Wanninkhof, R.; Wiltshire, A.; Zeng, N.

2014-09-01

379

Functionalization of carbon nanotubes  

NASA Technical Reports Server (NTRS)

Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H.sub.2 or F.sub.2 or C.sub.nH.sub.m) is irradiated to provide a cold plasma of selected target particles, such as atomic H or F, in a first chamber. The target particles are directed toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec.

Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

2007-01-01

380

Functionalization of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H2, or F2, or CnHm) is irradiated to provide a cold plasma of selected target particles, such as atomic H or F, in a first chamber. The target particles are directed toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec.

Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

2007-01-01

381

Integrated Carbon Observation System  

NASA Astrophysics Data System (ADS)

ICOS is a recently-launched, world-class research infrastructure dedicated to the monitoring and improved understanding of carbon sources and sinks. It consists of complementary, harmonized networks of long-term monitoring stations focusing on Europe and adjacent regions. The ICOS networks will comprise about 40 operational atmospheric stations (measuring atmospheric composition in greenhouse gases and other core parameters), ca. 30 ecosystem stations (measuring fluxes to and from ecosystems) and about 25 oceanic measurement platforms (including fixed time series stations, repeat hydrographic sections and voluntary observing ships). The station networks are expected to be operational in 2014. The networks will be coordinated through a set of central facilities: three Thematic Centres respectively for atmospheric, ecosystem and ocean data, and a Central Analytical Laboratory. The mission of the Thematic Centres is to process, validate and distribute data to end-users. ICOS will also set up a Carbon Portal dedicated to easy discovery of and access to data and elaborated products such as flux maps by end users. Through its Preparatory Phase Project (funded by the EU through FP7) ICOS is currently demonstrating its capability to monitor greenhouse gases across Europe at four atmospheric sites and four ecosystem sites, working in near real time with the Atmospheric and Ecosystem Thematic Centres. At this occasion, the instrumental packages, the experimental set up as well as protocols prepared for the standardized ICOS stations are tested. ICOS atmospheric measurements, in combination with a dedicated modelling framework, will allow estimating daily fluxes at a typical resolution of 50 km with a precision of ~40 gC m-2 yr-1. The ecosystem network informs on the small scale variability of fluxes and its drivers. When completed, ICOS will provide the essential long-term observations required to understand the present state and predict future behaviour of the global carbon cycle and greenhouse gases emissions. ICOS will notably provide key data for the monitoring and assessment of the impact of carbon sequestration and/or greenhouse gases emission reduction activities on global atmospheric composition levels.

Paris, J.-D.; Ciais, P.; Rivier, L.; Chevallier, F.; Dolman, H.; Flaud, J.-M.; Garrec, C.; Gerbig, C.; Grace, J.; Huertas, E.; Johannessen, T.; Jordan, A.; Levin, I.; Papale, D.; Valentini, R.; Watson, A.; Vesala, T.; ICOS-PP Consortium

2012-04-01

382

Carbon Nanotube Interconnect  

NASA Technical Reports Server (NTRS)

Method and system for fabricating an electrical interconnect capable of supporting very high current densities ( 10(exp 6)-10(exp 10) Amps/sq cm), using an array of one or more carbon nanotubes (CNTs). The CNT array is grown in a selected spaced apart pattern, preferably with multi-wall CNTs, and a selected insulating material, such as SiOw, or SiuNv is deposited using CVD to encapsulate each CNT in the array. An exposed surface of the insulating material is planarized to provide one or more exposed electrical contacts for one or more CNTs.

Li, Jun (Inventor); Meyyappan, Meyya (Inventor)

2006-01-01

383

Carbon-Nanotube Optoelectronics  

Microsoft Academic Search

\\u000a Semiconducting single-walled carbon nanotubes are direct-gap materials that\\u000a provide ideal systems for the study of photophysics in one-dimension. While\\u000a their excited states involve strongly bound 1D excitons, their single atomic\\u000a layer structure makes their optical properties especially sensitive to their\\u000a environment and external fields, thus allowing for their controlled modification. In\\u000a this chapter we review the properties of the excited

Phaedon Avouris; Marcus Freitag; Vasili Perebeinos

384

Carbonate fuel cell anodes  

DOEpatents

A molten alkali metal carbonates fuel cell porous anode of lithium ferrite and a metal or metal alloy of nickel, cobalt, nickel/iron, cobalt/iron, nickel/iron/aluminum, cobalt/iron/aluminum and mixtures thereof wherein the total iron content including ferrite and iron of the composite is about 25 to about 80 percent, based upon the total anode, provided aluminum when present is less than about 5 weight percent of the anode. A process is described for production of the lithium ferrite containing anode by slipcasting.

Donado, R.A.; Hrdina, K.E.; Remick, R.J.

1993-04-27

385

Carbonate fuel cell anodes  

DOEpatents

A molten alkali metal carbonates fuel cell porous anode of lithium ferrite and a metal or metal alloy of nickel, cobalt, nickel/iron, cobalt/iron, nickel/iron/aluminum, cobalt/iron/aluminum and mixtures thereof wherein the total iron content including ferrite and iron of the composite is about 25 to about 80 percent, based upon the total anode, provided aluminum when present is less than about 5 weight percent of the anode. A process for production of the lithium ferrite containing anode by slipcasting.

Donado, Rafael A. (Chicago, IL); Hrdina, Kenneth E. (Glenview, IL); Remick, Robert J. (Bolingbrook, IL)

1993-01-01

386

The Carbon Cycle Science Program  

NSDL National Science Digital Library

The US Global Change Research Program (USGCRP) provides this site with the purpose of supplying "critical unbiased scientific information on the fate of carbon dioxide in the environment to contribute to the ongoing public dialogue." The USGCRP's focus for the fiscal year 2000 is on determining the location, magnitude, and use of carbon sinks in North America. Sections of the site include Current Research Activities, Contacts, Program and Science Planning, and Meetings and Workshops. Users can download The Carbon Cycle Science Plan in .pdf format and also obtain specific, current information on the background and goals of the Carbon Cycle Science Program initiative.

387

Radial textured carbon nanoflake spherules  

NASA Astrophysics Data System (ADS)

A unique type of carbon structure, radial textured carbon nanoflake spherules, has been synthesized by a microwave plasma assisted chemical vapor deposition method. The spherules with a diameter of 1.2-35?m consist of a number of radially distributed carbon nanoflakes growing from a common core. The constituent nanoflakes are interlaced and perpendicular to the surface of spherules, forming a large amount of open edge planes. Thus, the carbon nanoflake spherules are isotropic graphite with a larger surface area and higher surface activity, which can be demonstrated by Raman scattering spectroscopy with two characteristic peaks of 860 and 1140cm-1.

Shang, N. G.; Staedler, T.; Jiang, X.

2006-09-01

388

Carbon-assisted flyer plates  

DOEpatents

A laser driven flyer plate utilizing an optical fiber connected to a laser. The end of the optical fiber has a layer of carbon and a metal layer deposited onto it. The carbon layer provides the laser induced plasma which is superior to the plasma produced from most metals. The carbon layer plasma is capable of providing a flatter flyer plate, converting more of the laser energy to driving plasma, promoting a higher flyer plate acceleration, and providing a more uniform pulse behind the plate. In another embodiment, the laser is in optical communication with a substrate onto which a layer of carbon and a layer of metal have been deposited.

Stahl, David B. (Los Alamos, NM); Paisley, Dennis L. (Santa Fe, NM)

1994-01-01

389

Carbon layers for integrated optics  

NASA Astrophysics Data System (ADS)

Study of fabrication and properties of the carbon layers by using the PACVD (Plasma Assisted Chemical Vapor Deposition) apparatus is reported. The layers were grown on silicon substrates with methane as the precursor and were then doped with the erbium ions by treating the fabricated samples in glycerin or in the solution of erbium nitrate. To obtain deeper erbium containing carbon layers (up to 1 ?m) the "sandwich method" was used based on repetition (three times) of carbon deposition and subsequent diffusion of erbium after which followed annealing in vacuum oven. The obtained results proved that it is in principle possible to fabricate the erbium containing carbon thin optical layers.

Prajzler, Vaclav; Huettel, Ivan; Schroefel, Josef; Nekvindova, Pavla; Gurovic, Jan; Mackova, Anna

2003-07-01

390

Exploring Marine Carbon Isotope Excursions  

NSDL National Science Digital Library

David Jones, Geology Department, Amherst College Topic: stable isotopes, geochemistry, oceanography, carbon cycle Course type: Upper level undergraduate course Description The exercise is designed to introduce ...

391

Carbon nanotube IR detectors (SV)  

SciTech Connect

Sandia National Laboratories (Sandia) and Lockheed Martin Corporation (LMC) collaborated to (1) evaluate the potential of carbon nanotubes as channels in infrared (IR) photodetectors; (2) assemble and characterize carbon nanotube electronic devices and measure the photocurrent generated when exposed to infrared light;(3) compare the performance of the carbon nanotube devices with that of traditional devices; and (4) develop and numerically implement models of electronic transport and opto-electronic behavior of carbon nanotube infrared detectors. This work established a new paradigm for photodetectors.

Leonard, F. L.

2012-03-01

392

The Evolution of Carbon Stars  

NASA Astrophysics Data System (ADS)

This dissertation is concerned with the nature of the carbon stars, unusual late-type stars in which the abundance of carbon in the photosphere is greater than that of oxygen. Data from the Infrared Astronomical Satellite (IRAS) survey has shown that carbon stars which were identified from optical surveys and those identified from the SiC dust features in their IRAS Low Resolution Spectrometer LRS spectra have different IRAS colours. The former (which will be referred to as visual carbon stars) are visually bright and have large excesses at 6 microns, while the latter group (which will be referred to as infrared carbon stars) have blackbody energy distributions. The origin of visual carbon stars has been discussed by Chan and Kwok (1988) based on the hypothesis of Willems and de Jong (1988). A complete sample of visual carbon stars detected by IRAS with 12 microns flux densities greater than 5 Jy was selected, and 207 LRS spectra were extracted for those sources without previous \\lrs data. Of these, 152 sources had new LRS spectra with reasonably good signal-to-noise ratio and 575 sources had previously released LRS spectra. All these spectra have been classified with the scheme of Volk and Cohen (1989). When the LRS spectra of these 727 IRAS CCGCS sources were examined, 15 were found to show the 9.7 microns silicate emission feature which is expected to occur only in an oxygen-rich circumstellar shell. Eight of these are reported for the first time in this dissertation. This group of visual carbon stars (hereafter called silicate carbon stars) may represent transition objects between oxygen-rich and carbon stars on the asymptotic giant branch (AGB) because the photosphere is carbon-rich while the circumstellar material resembles that from a typical M-type star. A radiative transfer dust shell model for these silicate carbon stars is presented. The model spectra produce excellent fits to the observed energy distributions of these silicate carbon stars. The J-type stars (^13C-rich carbon stars) have been suggested to be transition objects between M-type stars and C-type stars. An optical spectroscopic study of these silicate carbon stars was performed at the Dominion Astrophysical Observatory (DAO) in Victoria in 1991. CCGCS 1653, CCGCS 4222, CCGCS 4923 and CCGCS 5848 have been confirmed to be J stars. CCGCS 1158 and CCGCS 4729 are provisionally identified as J stars. A preliminary spectral analysis has also been carried out. Model calculations are presented on the evolution from the visual carbon stars to infrared carbon stars, and on the evolution of infrared carbon stars. A new empirical opacity function for the SiC grain is derived based on the LRS spectra of a selected sample of infrared carbon stars. A two-shell model has been developed with an oxygen-rich detached shell and a newly-forming SiC dust shell. The energy distributions of ~110 transition objects which are late-stage visual carbon stars or early-stage infrared carbon stars are fitted with this Interrupted Mass Loss Model. Furthermore, the model tracks successfully explain the "C" shaped distribution of the transition objects in the IRAS 12 microns/25 microns/60 microns colour-colour diagram. The energy distributions of ~150 infrared carbon stars are also matched with a radiative transfer dust shell model using only SiC dust. The colour evolution of infrared carbon stars can be explained with a continuous increase in mass loss rate on the AGB. An evolutionary scenario of AGB stars is suggested. There is a branching of M-type and C-type stars on the AGB with each branch evolving independently to the planetary nebula stage. The initial mass of the star in the main sequence may be the factor that determines which branch the star will follow. (SECTION: Dissertation Abstracts)

Chan, S. Josephine

1993-04-01

393

Refractory Oxidative-Resistant Ceramic Carbon Insulation  

NASA Technical Reports Server (NTRS)

High-temperature, lightweight, ceramic carbon insulation is prepared by coating or impregnating a porous carbon substrate with a siloxane gel derived from the reaction of an organodialkoxy silane and an organotrialkoxy silane in an acid or base medium in the presence of the carbon substrate. The siloxane gel is subsequently dried on the carbon substrate to form a ceramic carbon precursor. The carbon precursor is pyrolyzed, in an inert atmosphere, to form the ceramic insulation containing carbon, silicon, and oxygen. The carbon insulation is characterized as a porous, fibrous, carbon ceramic tile which is particularly useful as lightweight tiles for spacecraft.

Leiser, Daniel B. (Inventor); Hsu, Ming-Ta S. (Inventor); Chen, Timothy S. (Inventor)

2001-01-01

394

Swansea University Carbon Management Plan 2010 -2020 SUMMARY Swansea University  

E-print Network

). Hydrofluorocarbons (HFC), Perflurorocarbons (PFC) and Sulphur hexafluoride (SF6). Carbon emissions The term `carbon emissions. However, within the context of HEFCW `carbon emissions' more specifically means `carbon dioxide

Grant, P. W.

395

Lesson Summary Students will learn about different carbon  

E-print Network

in seawater - Carbon in marine animals and plants - Carbon in coal and natural gas - Carbon in oil - Carbon' * - Carbon dioxide in the atmosphere - Carbon in green plants - Carbon in animals - Carbon in soil - Carbon, but now (since the industrial revolution) the large scale burning of oil, coal and natural gas, along

Mojzsis, Stephen J.

396

46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether. 151.50-40 Section...Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl...

2013-10-01

397

46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether. 151.50-40 Section...Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl...

2014-10-01

398

46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether. 151.50-40 Section...Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl...

2012-10-01

399

46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether. 151.50-40 Section...Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl...

2011-10-01

400

46 CFR 151.50-40 - Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Additional requirements for carbon disulfide (carbon bisulfide) and ethyl ether. 151.50-40 Section...Requirements § 151.50-40 Additional requirements for carbon disulfide (carbon bisulfide) and ethyl...

2010-10-01

401

University of Aberdeen Carbon Management Plan  

E-print Network

of Aberdeen is committed to reducing its carbon footprint and to playing its part in limiting the worstUniversity of Aberdeen Carbon Management Plan Higher Education Carbon Management Programme working with Page 1 The University of Aberdeen Carbon Management Programme Carbon Management Plan (CMP

Levi, Ran

402

6, 34193463, 2006 Black carbon or  

E-print Network

), and the early studies on the environmental cycle of "black carbon" (BC) were summarized in the monograph BlackACPD 6, 3419­3463, 2006 Black carbon or brown carbon M. O. Andreae and A. Gelencs´er Title Page Chemistry and Physics Discussions Black carbon or brown carbon? The nature of light-absorbing carbonaceous

Paris-Sud XI, Université de

403

The Global Carbon Cycle Radiative forcing  

E-print Network

The Global Carbon Cycle Radiative forcing Global carbon reservoirs Glacial-interglacial cycles Anthropogenic CO2 Ocean-atmosphere partitioning Ocean carbon cycle Carbon distribution in the ocean;Geological timescales #12;Present day carbon cycle Gruber & Sarmiento (2002) #12;Glacial

Follows, Mick

404

Carbon Management Plan 1. Executive summary 5  

E-print Network

Carbon Management Plan June 2011 #12;2 #12;3 CONTENTS 1. Executive summary 5 2. Introduction 15 3. Background and context 16 4. Carbon management strategy 18 5. Carbon emissions baseline and projections 22 6. Past actions and achievements 30 7. Carbon Management Plan implementation 33 8. Carbon Management Plan

Haase, Markus

405

Electrical models for vertical carbon nanotube capacitors  

Microsoft Academic Search

We present electrical models for a carbon nanotube capacitor with high capacitance per unit area. We begin by introducing the concept of using vertically grown carbon nanotubes to develop a carbon nanotube capacitor. Three potential structures of the carbon nanotube capacitor are presented. We determine the capacitance per unit area for each structure. The carbon nanotube capacitor structures exhibit capacitances

Mark M. Budnik; Eric W. Johnson; Joshua D. Wood

2008-01-01

406

Forest carbon offsets in the United States  

Microsoft Academic Search

carbon weight in trees can be computed from dry weight of tree biomass by dividing by 2 as trees are roughly fifty percent carbon based on dry weight. Carbon weight can then be converted into CO2 weight by multiplying by 3.67, based on the molecular weights of carbon and carbon dioxide. According to Birdsey (1992), 731 million acres of forest

Burl Carraway; Weihuan Xu

2008-01-01

407

Materials property definition and generation for carbon-carbon and carbon phenolic materials  

NASA Technical Reports Server (NTRS)

A data base program to generate statistically significant material-property data for carbon-carbon and carbon phenolic materials to be used in designs of Space Shuttle is described. The program, which will provide data necessary for thermal and stress modeling of Shuttle nozzle and exit cone structures, includes evaluation of tension, compression, shear strength, shear modulus, thermal expansion, thermal conductivity, permeability, and emittance for both materials; the testing of carbon phenolic materials also includes CTE, off-gassing, pyrolysis, and RTG. Materials to be tested will be excised from Space Shuttle inlet, throat, and exit cone billets and modified involute carbon-carbon exit cones; coprocessed blocks, panels, and cylinders will also be tested.

Canfield, A. R.; Mathis, J. R.; Starrett, H. S.; Koenig, J. R.

1987-01-01

408

Role of activated carbon pellets in carbon dioxide removal  

Microsoft Academic Search

The removal of carbon dioxide from gas\\/air streams is more often becoming necessary in many industries for different purposes. In cryogenic air separation plant, air has to be free from carbon dioxide before its liquefaction otherwise blockage due to freezing of heat exchange equipment would result. Enrichment of methane in biogas to have fuel of higher calorific value can be

S. C Sarkar; A Bose

1997-01-01

409

Grafting carbon nanotubes onto carbon fiber by use of dendrimers  

Microsoft Academic Search

A novel method is developed for grafting carbon nanotubes (CNTs) onto the carbon fiber (CF) surface by use of dendrimers. CF surface is functionalized by an adsorbed dendrimers layer. After an oxidation treatment, CNTs with carboxyl, carbonyl or hydroxyl groups are grafted onto the amino-functionalized CFs via chemical interactions. Homogeneous multi-scale structures with different CNT densities and lengths are gained

Lei Mei; Xiaodong He; Yibin Li; Rongguo Wang; Chao Wang; Qingyu Peng

2010-01-01

410

Effects of Porosity on Strength of Carbon-Carbon Composites  

Microsoft Academic Search

Filament wound\\/CVD (Chemical Vapor Deposition) carbon-carbon composites have received considerable attention and application within the past few years because of their desirable characteristics such as high heat of ablation, thermal shock resistance, high strength at elevated temperatures, and chemical inertness. However, poor mechanical properties in the transverse direction have hampered the total effectiveness of these composites in some applications and

Gilbert William Brassell; James A. Horak; Barry Lynn Butler

1975-01-01

411

Carbon Code Requirements for voluntary carbon sequestration projects  

E-print Network

Documentation 7 2.3 Management plan and capacity 7 2.4 Management of risks and permanence 8 2.5 Management leakage 12 3.4 Project carbon sequestration 12 3.5 Net carbon sequestration 13 4. Environmental quality 14 management as part of modern sustainable forest management. Specific objectives of the Code include

412

Carbon dioxide sequestration in cement kiln dust through mineral carbonation.  

PubMed

Carbon sequestration through the formation of carbonates is a potential means to reduce CO2 emissions. Alkaline industrial solid wastes typically have high mass fractions of reactive oxides that may not require preprocessing, making them an attractive source material for mineral carbonation The degree of mineral carbonation achievable in cement kiln dust (CKD) underambienttemperatures and pressures was examined through a series of batch and column experiments. The overall extent and potential mechanisms and rate behavior of the carbonation process were assessed through a complementary set of analytical and empirical methods, including mass change, thermal analysis, and X-ray diffraction. The carbonation reactions were carried out primarily through the reaction of CO2 with Ca(OH)2, and CaCO3 was observed as the predominant carbonation product. A sequestration extent of over 60% was observed within 8 h of reaction without any modifications to the waste. Sequestration appears to follow unreacted core model theory where reaction kinetics are controlled by a first-order rate constant at early times; however, as carbonation progresses, the kinetics of the reaction are attenuated by the extent of the reaction due to diffusion control, with the extent of conversion never reaching completion. PMID:19368202

Huntzinger, Deborah N; Gierke, John S; Kawatra, S Komar; Eisele, Timothy C; Sutter, Lawrence L

2009-03-15

413

Three-dimensional helical carbon materials: Microcoiled carbon fibers, carbon nanocoils, carbon nanotubes: Synthesis, properties and applications  

NASA Astrophysics Data System (ADS)

Materials with a 3D-helical/spiral-structure in micron size have recently aroused a great deal of interests because of their helical morphology and unique properties. However, materials with a 3D helical structure are not commonly observed among industrially available materials. Researchers have been trying to synthesize various micro- and nano-sized 3D helical materials and are exploring the mechanisms, nature, and properties of these materials. Yet a systematic study on 3D helical carbon materials in micro- and nano-size has been missing. This research work is intended as a first step to fill this gap. Among various 3D helical materials, carbon element has stimulated great interests. Micro coiled carbon fibers, carbon nanocoils, and carbon nanotubes are major types of 3D helical carbon materials ranging from micron to nano size. Synthesis of these 3D helical carbon materials by a catalytic chemical vapor deposition method is presented in this thesis. It involves a pyrolysis of hydrocarbon gas (e.g. acetylene) over transition metals, such as Ni, Fe, and Co, at high reaction temperature (500--1000°C). Besides the conventional thermal filament chemical vapor deposition method, a novel microwave chemical vapor deposition (MWCVD) method has been developed to synthesize micro- and nano-sized 3D helical carbon materials economically. The faster heating and cooling processes associated with microwave CVD have potential for large-scale production in the near future. Compared with previously reported microwave plasma enhanced chemical vapor deposition (MWPECVD) method, this method does not require high vacuum and much higher deposition rate is another major advantage. It has been found in this work that microwave plays an important role on coil morphology formation for micro coiled carbon fibers and carbon nanocoils. The large temperature gradient around the catalytic particles could be the reason. Different reaction factors have been checked to optimize the deposition. Due to their extraordinary properties, carbon nanotubes have been expected to have wide applications. Efforts have been made on the synthesis of high quality carbon nanotubes economically in this work. A novel catalyst/catalyst support pair, iron/magnesium carbonate, has been developed for synthesis of multi-walled carbon nanotubes with high purity. The coil morphology is induced by insertion of pentagon-heptagon pairs into hexagonal network of nanotube wall periodically. Thorough purification of carbon nanotubes is always a concern before investigating their properties and potential applications. Impurities in raw carbon nanotube material have to be removed by chemical treatment. A couple of purification methods are presented in this work. Various techniques have been used to characterize these micro- and nano-3D materials, such as scanning electron microscopy (SEM), energy dispersive spectrum (EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer Emmett-Teller (BET), thermal gravimetric analysis (TGA), etc. Growth mechanisms are proposed based on the experimental and characterization results. It is verified that the nonuniform carbon deposition rate on catalyst particles leads to the bending of the carbon fiber/tubule, and hence results in the coil morphology. To conclude, the research work reported here is a systematic study on synthesis, characterizations, and applications of micro- and nano-3D helical carbon materials, such as micro coiled carbon fibers, carbon nanocoils and carbon nanotubes. A few suggestions for future research directions are also listed.

Xie, Jining

414

Friction behaviors of carbon\\/carbon composites with different pyrolytic carbon textures  

Microsoft Academic Search

Friction and wear properties of carbon\\/carbon (C\\/C) composites with a smooth laminar (SL), a medium textured rough laminar (RL) and a high textured RL pyrolytic carbon texture were investigated with a home-made laboratory scale dynamometer to simulate airplane normal landing (NL), over landing (OL) and rejected take-off (RTO) conditions. The morphology of worn surfaces at different braking levels was observed

Xiang Xiong; Bai-yun Huang; Jiang-hong Li; Hui-juan Xu

2006-01-01

415

Carbon Dioxide Carbonates in the Earth;s Mantle: Implications to the Deep Carbon Cycle  

SciTech Connect

An increase in the ionic character in C-O bonds at high pressures and temperatures is shown by the chemical/phase transformation diagram of CO{sub 2}. The presence of carbonate carbon dioxide (i-CO{sub 2}) near the Earth's core-mantle boundary condition provides insights into both the deep carbon cycle and the transport of atmospheric CO{sub 2} to anhydrous silicates in the mantle and iron core.

Yoo, Choong-Shik; Sengupta, Amartya; Kim, Minseob (Princeton); (WSU)

2012-05-22

416

Carbon Nanotube Purification  

NASA Technical Reports Server (NTRS)

A method for cleaning or otherwise removing amorphous carbon and other residues that arise in growth of a carbon nanotube (CNT) array. The CNT array is exposed to a plurality of hydroxyls or hydrogen, produced from a selected vapor or liquid source such as H2O or H2O2. and the hydroxyls or hydrogen (neutral or electrically charged) react with the residues to produce partly or fully dissolved or hydrogenated or hydroxylizated products that can be removed or separated from the CNT array. The hydroxyls or hydrogen can be produced by heating the CNT array, residue and selected vapor or liquid source or by application of an electromagnetic excitation signal with a selected frequency or range of frequencies to dissociate the selected vapor or liquid. The excitation frequency can be chirped to cover a selected range of frequencies corresponding to dissociation of the selected vapor or liquid. Sonication may be uscd to supplement dissociation of the H2O and/or H2O2.

Delzeit, Lance D. (Inventor); Delzeit, Clement J. (Inventor)

2005-01-01

417

Carbon nanotube array actuators  

NASA Astrophysics Data System (ADS)

Experimental investigations of highly vertically aligned carbon nanotubes (CNTs), also known as CNT-arrays, are the main focus of this paper. The free strain as result of an active material behavior is analyzed via a novel experimental setup. Previous test experiences of papers made of randomly oriented CNTs, also called Bucky-papers, reveal comparably low free strain. The anisotropy of aligned CNTs promises better performance. Via synthesis techniques like chemical vapor deposition (CVD) or plasma enhanced CVD (PECVD), highly aligned arrays of multi-walled carbon nanotubes (MWCNTs) are synthesized. Two different types of CNT-arrays are analyzed, morphologically first, and optically tested for their active characteristics afterwards. One type of the analyzed arrays features tube lengths of 750-2000 ?m with a large variety of diameters between 20 and 50 nm and a wave-like CNT-shape. The second type features a maximum, almost uniform, length of 12 ?m and a constant diameter of 50 nm. Different CNT-lengths and array types are tested due to their active behavior. As result of the presented tests, it is reported that the quality of orientation is the most decisive property for excellent active behavior. Due to their alignment, CNT-arrays feature the opportunity to clarify the actuation mechanism of architectures made of CNTs.

Geier, S.; Mahrholz, T.; Wierach, P.; Sinapius, M.

2013-09-01

418

Carbonic acid on Mars?  

NASA Astrophysics Data System (ADS)

For a long time carbonic acid (H 2CO 3) had defied many efforts for its detection by IR spectroscopic techniques. Recently H 2CO 3 has been synthesized at low temperature (?10-80 K), and stabilized up to ?250 K, by energetic ion irradiation of frozen targets made of H 2O:CO 2 ice mixtures (Moore and Khanna, Spectrochim. Acta47, 255-262, 1991; Moore et al., J, Geophys. Res.96(2), 17,541-17,545, 1991, DelloRusso et al., Geophys. Res.98(E3), 5505-5510, 1993; Brucato et al., Icarus 1996 (in press)) and by protonation of bicarbonate (Hage et al., J. Am. Chem. Soc.115, 8427-8431, 1993; J. Chem. Soc. Faraday Trans.91(17), 2823-2826, 1995). Its IR spectrum has been obtained. A comparison between the IR laboratory spectrum of H 2CO 3 with some spectra of Mars suggests that carbonic could be present on the surface and/or atmosphere of the red planet. Its firm identification requires the acquisition of better astronomical data possibly from space missions (e.g. Mars 96) and would be of primary relevance for both the organic and inorganic chemistry taking place on Mars.

Strazzulla, G.; Brucato, J. R.; Cimino, G.; Palumbo, M. E.

1996-11-01

419

Introduction to Carbonate Equilibrium  

NSDL National Science Digital Library

The activity asks students to make observations about what occurs when two effervescent antacid tablets are placed into a beaker of water. The Students work together in groups. There are three parts to the activity. In the first part, the tablets are dropped into tap water and student groups (2-4 students) must complete a series of question sheets (one per group) that guide them through thinking about the event. In the second part, a presentation on chemical equilibrium for the carbonate system is given. The starting point is the answers received in the first part. Basic chemical reactions for the carbonate system are presented including equilibrium expressions for each reaction and discussion about open and closed systems. At the end of class, a handout is given to the students. In the third part, three beakers (acidic, neutral and basic solutions, but not indicated) are placed together and two tablets are placed into each beaker. Students are split into two groups (8-12 students) and are asked to describe why the reactions are different. Discussion follows collection of student responses in each part. Once the chemical reactions and equilibrium expressions are presented, they are involved and referenced in all discussions.

michael stapleton

420

Carbon dioxide and climate  

SciTech Connect

Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

Not Available

1990-10-01

421

Intermediate Temperature Carbon - Carbon Composite Structures. CRADA Final Report  

SciTech Connect

The objective of this Cooperative Research and Development Agreement (CRADA) between UT-Battelle, LLC (the "Contractor") and Synterials, Inc. (the "Participant") was to demonstrate promising processing methods, which can lead to producing Carbon-Carbon Composites (CCC), with tensile and interlaminar properties comparable to those of organic matrix composites and environmental stability at 1200 F for long periods of time. The participant synthesized carbon-carbon composites with two different fiber coatings and three different matrices. Both parties evaluated the tensile and interlaminar properties of these materials and characterized the microstructure of the matrices and interfaces. It was found that fiber coatings of carbon and boron carbide provided the best environmental protection and resulted in composites with high tensile strength.

Lara-Curzio, Edgar [ORNL

2007-06-01

422

Compressed carbon nanotubes: A family of new multifunctional carbon allotropes  

PubMed Central

The exploration of novel functional carbon polymorphs is an enduring topic of scientific investigations. In this paper, we present simulations demonstrating metastable carbon phases as the result of pressure induced carbon nanotube polymerization. The configuration, bonding, electronic, and mechanical characteristics of carbon polymers strongly depend on the imposed hydrostatic/non-hydrostatic pressure, as well as on the geometry of the raw carbon nanotubes including diameter, chirality, stacking manner, and wall number. Especially, transition processes under hydrostatic/non-hydrostatic pressure are investigated, revealing unexpectedly low transition barriers and demonstrating sp2?sp3 bonding changes as well as peculiar oscillations of electronic property (e.g., semiconducting?metallic?semiconducting transitions). These polymerized nanotubes show versatile and superior physical properties, such as superhardness, high tensile strength and ductility, and tunable electronic properties (semiconducting or metallic). PMID:23435585

Hu, Meng; Zhao, Zhisheng; Tian, Fei; Oganov, Artem R.; Wang, Qianqian; Xiong, Mei; Fan, Changzeng; Wen, Bin; He, Julong; Yu, Dongli; Wang, Hui-Tian; Xu, Bo; Tian, Yongjun

2013-01-01

423

The kinetics of binding carbon dioxide in magnesium carbonate  

SciTech Connect

Humans currently consume about 6 Gigatons of carbon annually as fossil fuel. In some sense, the coal industry has a unique advantage over many other anthropogenic and natural emitters of CO{sub 2} in that it owns large point sources of CO{sub 2} from which this gas could be isolated and disposed of. If the increased energy demands of a growing world population are to be satisfied from coal, the implementation of sequestration technologies will likely be unavoidable. The authors` method of sequestration involves binding carbon dioxide as magnesium carbonate, a thermodynamically stable solid, for safe and permanent disposal, with minimal environmental impact. The technology is based on extracting magnesium hydroxide from common ultramafic rock for thermal carbonation and subsequent disposition. The economics of the method appear to be promising, however, many details of the proposed process have yet to be optimized. Realization of a cost effective method requires development of optimal technologies for efficient extraction and thermal carbonation.

Butt, D.P.; Lackner, K.S.; Wendt, C.H.; Vaidya, R.; Pile, D.L.; Park, Y.; Holesinger, T.; Harradine, D.M. [Los Alamos National Lab., NM (United States); Nomura, Koji [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.]|[Chichibu Onada Cement Co., Tokyo (Japan)

1998-08-01

424

Prospects for using carbon-carbon composites for EMI shielding  

NASA Technical Reports Server (NTRS)

Since pyrolyzed carbon has a higher electrical conductivity than most polymers, carbon-carbon composites would be expected to have higher electromagnetic interference (EMI) shielding ability than polymeric resin composites. A rule of mixtures model of composite conductivity was used to calculate the effect on EMI shielding of substituting a pyrolyzed carbon matrix for a polymeric matrix. It was found that the improvements were small, no more than about 2 percent for the lowest conductivity fibers (ex-rayon) and less than 0.2 percent for the highest conductivity fibers (vapor grown carbon fibers). The structure of the rule of mixtures is such that the matrix conductivity would only be important in those cases where it is much higher than the fiber conductivity, as in metal matrix composites.

Gaier, James R.

1990-01-01

425

Comparison of carbon onions and carbon blacks as conductive additives for carbon supercapacitors in organic electrolytes  

NASA Astrophysics Data System (ADS)

This study investigates carbon onions (?400 m2 g-1) as a conductive additive for supercapacitor electrodes of activated carbon and compares their performance with carbon black with high or low internal surface area. We provide a study of the electrical conductivity and electrochemical behavior between 2.5 and 20 mass% addition of each of these three additives to activated carbon. Structural characterization shows that the density of the resulting film electrodes depends on the degree of agglomeration and the amount of additive. Addition of low surface area carbon black (?80 m2 g-1) enhances the power handling of carbon electrodes but significantly lowers the specific capacitance even when adding small amounts of carbon black. A much lower decrease in specific capacitance is observed for carbon onions and the best values are seen for carbon black with a high surface area (?1390 m2 g-1). The overall performance benefits from the addition of any of the studied additives only at either high scan rates and/or electrolytes with high ion mobility. Normalization to the volume shows a severe decrease in volumetric capacitance and only at high current densities nearing 10 A g-1 we can see an improvement of the electrode capacitance.

Jäckel, N.; Weingarth, D.; Zeiger, M.; Aslan, M.; Grobelsek, I.; Presser, V.

2014-12-01

426

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

NASA Technical Reports Server (NTRS)

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(TradeMark) 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.

Jaworske, Donald A.

2006-01-01

427

Carbon Cycle Discussion After the warm-up quiz, discuss the carbon cycle.  

E-print Network

Carbon Cycle Discussion After the warm-up quiz, discuss the carbon cycle. Carbon is one: a reservoir where the stuff goes; carbon sink: ocean, landfills, trees Carbon cycling is a type the youtube video linked from the powerpoint on carbon cycling if there is extra time. #12;

Carrington, Emily

428

Production of precipitated calcium carbonate from calcium silicates and carbon dioxide  

Microsoft Academic Search

The possibilities for reducing carbon dioxide emissions from the pulp and paper industry by calcium carbonation are presented. The current precipitated calcium carbonate (PCC) production uses mined, crushed calcium carbonate as raw materials. If calcium silicates were used instead, carbon dioxide emissions from the calcination of carbonates would be eliminated. In Finland, there could, thus, be a potential for eliminating

Sebastian Teir; Sanni Eloneva; Ron Zevenhoven

2005-01-01

429

A chemical method to graft carbon nanotubes onto a carbon fiber  

Microsoft Academic Search

A simple method is developed for grafting carbon nanotubes (CNTs) onto a carbon fiber surface. CNT and carbon fiber undergo an oxidation treatment. Oxidation generates oxygen, like carboxyl, carbonyl or hydroxyl groups, or amine groups on nanotubes and carbon fiber surface. Functionalized CNTs are dispersed in a solvent and deposited on carbon fibers. The bonds between CNT and carbon fiber

Abdelghani Laachachi; Alexandre Vivet; Gérard Nouet; Bessem Ben Doudou; Christophe Poilâne; Jun Chen; Jin Bo bai; M'Hamed Ayachi

2008-01-01

430

A study on Low-Carbon City Proper Planning based on Carbon Footprint  

Microsoft Academic Search

The research tool of Carbon Footprint was brought forward to formulate Low-Carbon City Proper Planning better. In order to accommodate the long range and uncertainty in Low-Carbon City Proper planning, for example, Beijing Shijingshan District, all kinds of Carbon Footprint and the capacity of Carbon sink of city proper were calculated and analyzed by the computing method of Carbon Footprint,

Bo Wu; Wei-hua Zeng

2011-01-01

431

Carbon recycling in ophiolite-hosted carbonates, Oman-UAE  

NASA Astrophysics Data System (ADS)

Large-scale surface and subsurface freshwater carbonate deposits of probable Quaternary age have formed on the Oman-UAE ophiolite. Here, serpentinisation reactions in ultramafic rocks have produced calcite and magnesite. These carbonates are frequently cited as examples of natural atmospheric CO2 sequestration, but the possibility of carbon recycling has not been addressed. The aim of this study is to assess the degree of atmospheric CO2 being incorporated into carbonates versus that which has been recycled from alternative sources such as soil CO2, or limestones that underlie the ophiolite. This has been determined through ?13C/?18O, 87Sr/86Sr and 14C analysis of all major carbonate lithofacies identified. Our analyses of modern carbonate crusts forming on the surface of stagnant hyperalkaline (pH >11) waters show highly depleted ?13C and ?18O values (-25.5‰ ×0.5 PDB and -16.8‰ ×0.5 PDB respectively). This depletion has been attributed to a kinetic isotope effect occurring during atmospheric CO2 exchange with Ca(OH)2 hyperalkaline waters [1]. By comparison, inactive travertine deposits show a large range in ?13C (-10.5 to -21.8‰ PDB) which lies on a trajectory from the composition of modern crusts towards bicarbonate fluids in equilibrium with soil CO2. We interpret this trend as being produced by the mixing of different carbon sources, either at the time of formation or during later alteration. Modern carbonates and inactive travertines also have 87Sr/86Sr ratios and Sr concentrations similar to Cretaceous and Tertiary limestones which surround the ophiolite, whilst subsurface veins also display 87Sr/86Sr ratios similar to these Cretaceous limestones. Carbon recycling can also be determined with 14C. Modern atmospheric CO2 has a global average of 105-106% modern 14C (pMC), therefore freshwater carbonates forming solely from atmospheric CO2 would be expected to contain >100 pMC. However, modern carbonates display varied results from 94.5-101.4 pMC. Low values could be caused by meteoric waters incorporating 14C 'dead' carbon through the dissolution of limestones and/or uptake of soil CO2. This 'dead' carbon would then be assimilated into veins and surface deposits, offsetting pMC values. Inactive travertines show significant fluctuations in 14C values within a single hand sample, where stratigraphically younger samples give older radiocarbon 'ages' outside of error. These fluctuations may have been caused by the presence of limestone sourced 'dead' carbon in waters at time of formation, surface runoff containing soil CO2 or by later recrystallisation. Isotopic evidence indicates that mixing of contemporary atmospheric carbon and recycled older carbon has taken place during the on-going carbonation of the Oman-UAE ophiolite sequence. Failure to account for this recycled carbon could lead to inaccurate estimates of natural CO2 sequestration rates. References [1] Clark, I.D. and Fontes, J. (1990) Palaeoclimatic reconstruction in Northern Oman based on carbonates from hyperalkaline groundwaters. Quaternary Res, 33, 320-336

Stephen, A.; Jenkin, G. R.; Smith, D. J.; Styles, M. T.; Naden, J.; Boyce, A. J.; Bryant, C. L.

2013-12-01

432

Impregnating Coal With Calcium Carbonate  

NASA Technical Reports Server (NTRS)

Relatively inexpensive process proposed for impregnating coal with calcium carbonate to increase rates of gasification and combustion of coal and to reduce emission of sulfur by trapping sulfur in calcium sulfide. Process involves aqueous-phase reactions between carbon dioxide (contained within pore network of coal) and calcium acetate. Coal impregnated with CO2 by exposing it to CO2 at high pressure.

Sharma, Pramod K.; Voecks, Gerald E.; Gavalas, George R.

1991-01-01

433

Carbon Nanotubes for Polymer Photovoltaics  

Microsoft Academic Search

Carbon nanotubes are being investigated for optical absorption, exciton dissociation, and carrier transport in polymer photovoltaic devices. In the present work, single wall carbon nanotubes (SWNTs) were synthesized by an Alexandrite pulsed laser vaporization reactor at standard conditions and purified based upon our previously reported TOP procedure. The SWNTs were dispersed in polymer composites for pure MEH-PPV, pure P3HT, and

Annick Anctil; Roberta Dileo; Chris Schauerman; Brian Landi; Ryne Raffaelle

2007-01-01

434

Polymer Nanocomposites Containing Carbon Nanotubes  

Microsoft Academic Search

We review the present state of polymer nanocomposites research in which the fillers are single- wall or multiwall carbon nanotubes. By way of background we provide a brief synopsis about carbon nanotube materials and their suspensions. We summarize and critique various nanotube\\/polymer composite fabrication methods including solution mixing, melt mixing, and in situ polymerization with a particular emphasis on evaluating

Mohammad Moniruzzaman; Karen I. Winey

2006-01-01

435

Structural flexibility of carbon nanotubes  

Microsoft Academic Search

We report high resolution electron microscope (HREM) observations and atomistic simulations of the bending of single and multi-walled carbon nanotubes under mechanical duress. Single and multiple kinks are observed at high bending angles. Their occurrence is quantitatively explained by the simulations, which use a realistic many-body potential for the carbon atoms. We show that the bending is fully reversible up

Sumio Iijima; Charles Brabec; Amitesh Maiti; Jerzy Bernholc

1996-01-01

436

Carbon Nanotube Nucleated Polymer Crystallization  

Microsoft Academic Search

Crystallinity studies were performed on carbon nanotube?doped Poly(m?phenylenevinylene?co?2,5?dioctyloxy?p?phenylenevinylene) (PmPV) and Poly (vinyl alcohol) (PVOH). Differential Scanning Calorimetry (DSC) of the composites verified that carbon nanotubes nucleate polymer crystallization.

K. P. Ryan; M. Cadek; A. Drury; M. Ruether; W. J. Blau; J. N. Coleman

2005-01-01

437

Plasmachemical Synthesis of Carbon Suboxide  

E-print Network

A nonthermal carbon monoxide plasma is known to produce a solid deposition which is thought to be a polymer of carbon suboxide (C3O2); however there are very few investigations of this deposition in the literature. This thesis contains an analysis...

Geiger, Robert

2012-12-11

438

Determining total carbon in hydrazine  

NASA Technical Reports Server (NTRS)

Procedure incorporates modified pyrolysis train. Samples are vaporized before entering furnace to be pyrolyzed at 850 C + or - 25 C. Direct collection of pyrolyzed gas reduces loss of carbon dioxide. Infrared spectroscopy can be used to analyze samples for carbon dioxide content.

Davis, E. E.

1977-01-01

439

Carbon budgets in symbiotic associations  

SciTech Connect

Methods are described which permit the estimation of daily budgets for photosynthetically fixed carbon in any alga-invertebrate symbiosis. Included is a method for estimating total daily translocation which does not involve the use of C-14. A daily carbon budget for a shallow water symbiotic reef coral is presented.

Muscatine, L.; Falkowski, P.G.; Dubinsky, Z.

1983-01-01

440

Carbon Sequestration in Campus Trees  

NSDL National Science Digital Library

In this activity, students use a spreadsheet to calculate the net carbon sequestration in a set of trees; they will utilize an allometric approach based upon parameters measured on the individual trees. They determine the species of trees in the set, measure trunk diameter at a particular height, and use the spreadsheet to calculate carbon content of the tree using forestry research data.

Robert S. Cole

441

Ongoing transients in carbonate compensation  

Microsoft Academic Search

Uptake of anthropogenic CO2 is acidifying the oceans. Over the next 2000 years, this will modify the dissolution and preservation of sedimentary carbonate. By coupling new formulas for the positions of the calcite saturation horizon, zsat, the compensation depth, zcc, and the snowline, zsnow, to a biogeochemical model of the oceanic carbonate system, we evaluate how these horizons will change

Bernard P. Boudreau; Jack J. Middelburg; Andreas F. Hofmann; Filip J. R. Meysman

2010-01-01

442

Is Carbon Hard or Soft?  

NSDL National Science Digital Library

The representation shows differences in the arrangement of carbon atoms that make up diamonds and graphite. Through text and pictures, the resource describes the difference in arrangement of two different carbon allotropes. The text relates the differences in arrangements to differences in the hardness (properties) of the materials.

443

CARBON NANOTUBES AS MULTIPOLLUTANT SORBENTS  

EPA Science Inventory

Exploratory Research Program Project - Carbon nanotubes (CNTs) are formed from graphite (or graphene) sheets rolled into tubes, typically with diameters of 1 - 10 nm and lengths of 200 - 500 nm. Carbon nanotubes have unique electrical properties that have led to interest in thei...

444

SOURCE ASSESSMENT: CARBON BLACK MANUFACTURE  

EPA Science Inventory

The report summarizes the assessment of air emissions from the manufacture of carbon black, currently manufactured in the U.S. by two major processes: thermal and oil furnace. Sources of atmospheric emissions within oil furnace plants (about 90% of the 30 U.S. carbon black plants...

445

Carbon nanotubes: The solar approach  

Microsoft Academic Search

Using the same experimental set-up as for the solar production of fullerenes, we can also produce carbon nanotubes by direct vaporization of a mixture of powdered carbon and catalyst (Co, Ni, Y). The structure of the nanotubes is strongly dependent on the experimental conditions (pressure and flow rate of Ar gas) and we can obtain either multi-walled nanotubes or ropes

D. Laplaze; P. Bernier; W. K. Maser; G. Flamant; T. Guillard; A. Loiseau

1998-01-01

446

Carbon partitioning to cellulose synthesis  

Microsoft Academic Search

This article discusses the importance and implications of regulating carbon partitioning to cellulose synthesis, the characteristics of cells that serve as major sinks for cellulose deposition, and enzymes that participate in the conversion of supplied carbon to cellulose. Cotton fibers, which deposit almost pure cellulose into their secondary cell walls, are referred to as a primary model system. For sucrose

Candace H. Haigler; Milka Ivanova-Datcheva; Patrick S. Hogan; Vadim V. Salnikov; Sangjoon Hwang; Kirt Martin; Deborah P. Delmer

2001-01-01

447

DIALKYL CARBONATES AS LUBRICANT ADDITIVES  

Technology Transfer Automated Retrieval System (TEKTRAN)

It has been previously reported that dialkyl carbonates represent attractive lubricants, in part, to their ampiphilic nature and their decomposition to non-corrosive simple alcohols and carbon dioxide. Members of our labs previously examined such materials as additives for biodiesel applications an...

448

Hydrogen storage in carbon nanostructures  

Microsoft Academic Search

Carbon nanotubes have been known for more than 10 years. It is a challenge to fill their unique tubular structure with metals and gases. Especially, the absorption of hydrogen in single wall nanotubes has attracted many research groups worldwide. The values published for the quantity of hydrogen absorbed in nanostructured carbon materials varies between 0.4 and 67 mass%. With the

A. Züttel; P. Sudan; Ph. Mauron; T. Kiyobayashi; Ch. Emmenegger; L. Schlapbach

2002-01-01

449

Carbon dioxide and terrestrial ecosystems  

Microsoft Academic Search

This book is a summary of the current research which addresses the effects of elevated carbon dioxide on terrestrial ecosystems and an identification of significant unresolved issues. Chapters address the carbon dioxide effects on trees and forests, unmanaged herbaceous ecosystems, and crops. Included are experimental studies, conceptual models, general mathematical models, dynamic simulation models.

G. W. Koch; H. A. Mooney

1996-01-01

450

Permafrost soils and carbon cycling  

NASA Astrophysics Data System (ADS)

Knowledge of soils in the permafrost region has advanced immensely in recent decades, despite the remoteness and inaccessibility of most of the region and the sampling limitations posed by the severe environment. These efforts significantly increased estimates of the amount of organic carbon stored in permafrost-region soils and improved understanding of how pedogenic processes unique to permafrost environments built enormous organic carbon stocks during the Quaternary. This knowledge has also called attention to the importance of permafrost-affected soils to the global carbon cycle and the potential vulnerability of the region's soil organic carbon (SOC) stocks to changing climatic conditions. In this review, we briefly introduce the permafrost characteristics, ice structures, and cryopedogenic processes that shape the development of permafrost-affected soils, and discuss their effects on soil structures and on organic matter distributions within the soil profile. We then examine the quantity of organic carbon stored in permafrost-region soils, as well as the characteristics, intrinsic decomposability, and potential vulnerability of this organic carbon to permafrost thaw under a warming climate. Overall, frozen conditions and cryopedogenic processes, such as cryoturbation, have slowed decomposition and enhanced the sequestration of organic carbon in permafrost-affected soils over millennial timescales. Due to the low temperatures, the organic matter in permafrost soils is often less humified than in more temperate soils, making some portion of this stored organic carbon relatively vulnerable to mineralization upon thawing of permafrost.

Ping, C. L.; Jastrow, J. D.; Jorgenson, M. T.; Michaelson, G. J.; Shur, Y. L.

2015-02-01

451

4, 317348, 2007 Lateral carbon  

E-print Network

BGD 4, 317­348, 2007 Lateral carbon exchange in a tidal mangrove creek S. Bouillon et al. Title mangrove creek (Ras Dege, Tanzania) S. Bouillon 1,2 , J. J. Middelburg 2 , F. Dehairs 1 , A. V. Borges 3, France 317 #12;BGD 4, 317­348, 2007 Lateral carbon exchange in a tidal mangrove creek S. Bouillon et al

Boyer, Edmond

452

Diamond-like amorphous carbon  

Microsoft Academic Search

Diamond-like carbon (DLC) is a metastable form of amorphous carbon with significant sp3 bonding. DLC is a semiconductor with a high mechanical hardness, chemical inertness, and optical transparency. This review will describe the deposition methods, deposition mechanisms, characterisation methods, electronic structure, gap states, defects, doping, luminescence, field emission, mechanical properties and some applications of DLCs. The films have widespread applications

J. Robertson

2002-01-01

453

Carbon emission from farm operations  

Microsoft Academic Search

This manuscript is a synthesis of the available information on energy use in farm operations, and its conversion into carbon equivalent (CE). A principal advantage of expressing energy use in terms of carbon (C) emission as kg CE lies in its direct relation to the rate of enrichment of atmospheric concentration of CO2. Synthesis of the data shows that estimates

R Lal

2004-01-01

454

Viewpoint Carbon-negative biofuels  

Microsoft Academic Search

Current Kyoto-based approaches to reducing the earth's greenhouse gas problem involve looking for ways to reduce emissions. But these are palliative at best, and at worst will allow the problem to get out of hand. It is only through sequestration of atmospheric carbon that the problem can be solved. Carbon-negative biofuels represent the first potentially huge assault on the problem,

John A. Mathews

455

Short communication Diffusion of carbon in austenite  

E-print Network

carbon concentration gradients at the transformation interfacesinvolved in suchreactionsmakesit. In a concentration gradient, a carbon atom attempting random motion therefore 'sees'an exaggerated differenceinShort communication Diffusion of carbon in austenite H. K. D. H. Bhadeshia The concentration

Cambridge, University of

456

21 CFR 582.1619 - Potassium carbonate.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2011-04-01 false Potassium carbonate. 582.1619 Section 582.1619...General Purpose Food Additives § 582.1619 Potassium carbonate. (a) Product. Potassium carbonate. (b) Conditions of use....

2011-04-01

457

ASSESSMENT OF BUILDING LIFECYLE CARBON EMISSIONS  

E-print Network

Even though the Carbon Capture & Sequestration Technologies (CC & ST) program at the Massachusetts Institute of Technology initiated carbon emission research in late 1990s (CSI, 2013), carbon emissions has only become a ...

Kwok, George

2014-05-31

458

21 CFR 582.1425 - Magnesium carbonate.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Magnesium carbonate. 582.1425 Section 582.1425...General Purpose Food Additives § 582.1425 Magnesium carbonate. (a) Product. Magnesium carbonate. (b) Conditions of use....

2010-04-01

459

46 CFR 153.1040 - Carbon disulfide.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Carbon disulfide. 153.1040 Section 153...Special Cargo Procedures § 153.1040 Carbon disulfide. (a) No person may load, carry, or discharge carbon disulfide unless the cargo tank...

2014-10-01

460

46 CFR 153.1040 - Carbon disulfide.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Carbon disulfide. 153.1040 Section 153...Special Cargo Procedures § 153.1040 Carbon disulfide. (a) No person may load, carry, or discharge carbon disulfide unless the cargo tank...

2013-10-01

461

46 CFR 153.1040 - Carbon disulfide.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Carbon disulfide. 153.1040 Section 153...Special Cargo Procedures § 153.1040 Carbon disulfide. (a) No person may load, carry, or discharge carbon disulfide unless the cargo tank...

2012-10-01

462

21 CFR 582.1425 - Magnesium carbonate.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 2014-04-01 false Magnesium carbonate. 582.1425 Section 582.1425...General Purpose Food Additives § 582.1425 Magnesium carbonate. (a) Product. Magnesium carbonate. (b) Conditions of use....

2014-04-01

463

21 CFR 582.1425 - Magnesium carbonate.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2011-04-01 false Magnesium carbonate. 582.1425 Section 582.1425...General Purpose Food Additives § 582.1425 Magnesium carbonate. (a) Product. Magnesium carbonate. (b) Conditions of use....

2011-04-01

464

21 CFR 582.1425 - Magnesium carbonate.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 2013-04-01 false Magnesium carbonate. 582.1425 Section 582.1425...General Purpose Food Additives § 582.1425 Magnesium carbonate. (a) Product. Magnesium carbonate. (b) Conditions of use....

2013-04-01

465

21 CFR 582.1425 - Magnesium carbonate.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 2012-04-01 false Magnesium carbonate. 582.1425 Section 582.1425...General Purpose Food Additives § 582.1425 Magnesium carbonate. (a) Product. Magnesium carbonate. (b) Conditions of use....

2012-04-01

466

21 CFR 184.1191 - Calcium carbonate.  

Code of Federal Regulations, 2011 CFR

...As a byproduct in the “Lime soda process”; (2) By precipitation of calcium carbonate from calcium hydroxide in the “Carbonation process”; or (3) By precipitation of calcium carbonate from calcium chloride in the “Calcium...

2011-04-01

467

The Carbon Crisis in 90 Seconds  

NSDL National Science Digital Library

This video features a short animated sequence that illustrates the difference between young and old carbon released into the atmosphere from the consumption of food (young carbon) and the burning of fossil fuels (old carbon).

NASA

468

21 CFR 184.1240 - Carbon dioxide.  

Code of Federal Regulations, 2010 CFR

...Drugs 3 2010-04-01 2009-04-01 true Carbon dioxide. 184.1240 Section 184.1240 Food...Specific Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2 , CAS...

2010-04-01

469

46 CFR 153.1040 - Carbon disulfide.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Carbon disulfide. 153.1040 Section 153...Special Cargo Procedures § 153.1040 Carbon disulfide. (a) No person may load, carry, or discharge carbon disulfide unless the cargo tank...

2010-10-01

470

46 CFR 153.1040 - Carbon disulfide.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Carbon disulfide. 153.1040 Section 153...Special Cargo Procedures § 153.1040 Carbon disulfide. (a) No person may load, carry, or discharge carbon disulfide unless the cargo tank...

2011-10-01

471

21 CFR 582.1619 - Potassium carbonate.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Potassium carbonate. 582.1619 Section 582.1619...General Purpose Food Additives § 582.1619 Potassium carbonate. (a) Product. Potassium carbonate. (b) Conditions of use....

2010-04-01

472

Carbon Footprint Exercise  

NSDL National Science Digital Library

Step 1. Students are asked to keep track of their energy use from a variety of sources (heating/cooling, electricity, transportation, secondary emissions, etc) during the 9 days of Thanksgiving break, when many of them are likely to travel. They use the total for the 9 days that they calculated using an online calculator to estimate their yearly footprint and compare it to US and world averages. For most of them, the amount of carbon emitted during those 9 days is quite large because of airplane travel or long-distance driving. However, using a week of break when many students will travel allows them to become aware of the significance of transportation in carbon emissions. We provided a table with electricity and heating/cooling bills for various residence halls for students who stay on campus during the break. Step 2. Students complete an online survey where they are asked to enter the values that they have obtained for the various components of the calculator, perform some simple calculations and compare their annual footprint to the U.S. average. We used SurveyGizmo for the survey because it allows to download the data in a spreadsheet format and has some limited plotting features. The free version allows a maximum of 250 submissions, the Basic version ($19 per month, can be canceled at any time) has unlimited submissions. Step 3. Students write an essay through BlackBoard/WebCT (Assignment). A few guiding questions are provided for this essay where students reflect on the results of their impact on the global carbon budget, what they found surprising, and if they plan to make any changes to their lifestyle to limit their impact. No length limit is set for the essay. The guidelines and components of this assignment are available on a wiki page. The three steps can be implemented in BlackBoard/WebCT as a Lesson Plan with links to the online calculator (step 1), to the survey (step 2), and to the Assignment/essay (step 3).

Cinzia Cervato

473

The carbon brace  

PubMed Central

Background The CMCR brace (Corset MonocoqueCarbone respectant la Respiration –which means Monoshell Carbon Brace respecting Breathing) is an innovative brace, used in orthopaedic treatment for progressive thoracic, thoraco-lumbar or combined scoliosis, whatever their etiology. It can be used at the very young age without disrupting the chest growth, but should be kept for reducible scoliosis in older teenagers. Brace description and principles The CMCR brace is monoshell while retaining the corrective principle of the polyvalve Lyon brace with one or two supports (brace “pads”) located on hump(s).In contrast to Lyon brace made of plexidur and structured by metal reinforcement with adjustable but fixed localized supports, the CMCR brace is made of polyethylene and carbon with adjustable and mobile supports. This mobility provides a permanent pressure, which varies depending on ribs and spine movements. The correction is obtained without spinal extension so that each respiratory movement takes part in a gradual return to dorsal kyphosis. Results Results were presented in two published analysis: •?In the first retrospective study about 115 patients, French-published in the Annals of Physical Medicine and Rehabilitation (2005), the CMCR brace stabilized moderate scoliosis, decreased the vital capacity (VC) of 13% compared to the VC without brace, and did not have sufficient impact on the hump reduction. Treatment had better results when started at Risser 3 or 4 than Risser 0, 1, 2. The brace was then modified to increase the dorsal pad pressure and the location of correction forces was defined more precisely through the use of 3D analysis. •?The second study published in Scoliosis (2011) mainly focused on the impact on VC at brace setting up and followed a cohort of 90 patients treated with CMCR. Girls as well as boys increased VC during treatment, and at brace definitive removal, VC had increased of 21% from the initial value, whereas the theoretical VC at the same time rose by 18%. The difference between the time where the child actually wears its brace and the time asked by the clinician for the brace to be worn is only 1 hour, which means that this brace is accepted by teenagers. Conclusions Orthopaedic treatment is still a heavy treatment for teenagers in growth period. This orthosis is designed to partly maintain spine and chest mobility. We hope so to have part in improving life conditions of these teenagers, compared to those treated with rigid braces. PMID:23409701

2013-01-01

474

Ex situ aqueous mineral carbonation  

SciTech Connect

The U.S. Department of Energy's National Energy Technology Laboratory (NETL) located in Albany, OR (formerly the Albany Research Center) has studied ex situ mineral carbonation as a potential option for carbon dioxide sequestration. Studies focused on the reaction of Ca-, Fe-, and Mg-silicate minerals with gaseous CO{sub 2} to form geologically stable, naturally occurring solid carbonate minerals. The research included resource evaluation, kinetic studies, process development, and economic evaluation. An initial cost estimate of about $69/ton of CO{sub 2} sequestered was improved with process improvements to about 54/ton. The scale of ex situ mineral carbonation operations, requiring about 55,000 tons of mineral to carbonate, the daily CO{sub 2} emissions from a 1-GW, coal-fired power plant, may make such operations impractical. 23 refs., 4 figs., 5 tabs.

Stephen J. Gerdemann; William K. O'Connor; David C. Dahlin; Larry R. Penner; Hank Rush [National Energy Technology Laboratory, Albany, OR (United States)

2007-04-01

475

Natural materials for carbon capture.  

SciTech Connect

Naturally occurring clay minerals provide a distinctive material for carbon capture and carbon dioxide sequestration. Swelling clay minerals, such as the smectite variety, possess an aluminosilicate structure that is controlled by low-charge layers that readily expand to accommodate water molecules and, potentially, carbon dioxide. Recent experimental studies have demonstrated the efficacy of intercalating carbon dioxide in the interlayer of layered clays but little is known about the molecular mechanisms of the process and the extent of carbon capture as a function of clay charge and structure. A series of molecular dynamics simulations and vibrational analyses have been completed to assess the molecular interactions associated with incorporation of CO2 in the interlayer of montmorillonite clay and to help validate the models with experimental observation.

Myshakin, Evgeniy M. (National Energy Technology Laboratory, Pittsburgh, PA); Romanov, Vyacheslav N. (National Energy Technology Laboratory, Pittsburgh, PA); Cygan, Randall Timothy

2010-11-01

476

Method for producing carbon nanotubes  

DOEpatents

Method for producing carbon nanotubes. Carbon nanotubes were prepared using a low power, atmospheric pressure, microwave-generated plasma torch system. After generating carbon monoxide microwave plasma, a flow of carbon monoxide was directed first through a bed of metal particles/glass beads and then along the outer surface of a ceramic tube located in the plasma. As a flow of argon was introduced into the plasma through the ceramic tube, ropes of entangled carbon nanotubes, attached to the surface of the tube, were produced. Of these, longer ropes formed on the surface portion of the tube located in the center of the plasma. Transmission electron micrographs of individual nanotubes revealed that many were single-walled.

Phillips, Jonathan (Santa Fe, NM); Perry, William L. (Jemez Springs, NM); Chen, Chun-Ku (Albuquerque, NM)

2006-02-14

477

Molecular Structure of Carbon Dioxide  

NSDL National Science Digital Library

Carbon dioxide was first described in the 17th century by Jan Baptist van Helmont, a Belgium chemist. The chemical CO2 is released into the atmosphere when carbon-containing fossil fuels like oil, natural gas, and coal are burned in air. It is also produced by various microorganisms in fermentation and is breathed out by animals. Plants absorb carbon dioxide during photosynthesis, using both the carbon and the oxygen to construct carbohydrates. Every year the amount of CO2 in the atmosphere is increasing. CO2 build-up in the atmosphere is caused by deforestation, therefore reducing the number of trees available to absorb CO2. Excess CO2 in the environment causes Global Warming and the Greenhouse Effect. It is also toxic to humans since inhalation of large amounts of CO2 can cause suffocation. Some beverages, such as beer and sparkling wine contain carbon dioxide as a result of fermentation.

2002-08-15

478

Processing, characterization and modeling of carbon nanofiber modified carbon/carbon composites  

NASA Astrophysics Data System (ADS)

Carbon/Carbon (C/C) composites are used in high temperature applications because they exhibit excellent thermomechanical properties. There are several challenges associated with the processing of C/C composites that include long cycle times, formation of closed porosity within fabric woven architecture and carbonization induced cracks that can lead to reduction of mechanical properties. This work addresses various innovative approaches to reduce processing uncertainties and thereby improve thermomechanical properties of C/C by using vapor grown carbon nanofibers (VGCNFs) in conjunction with carbon fabric and precursor phenolic matrix. The different aspects of the proposed research contribute to understanding of the translation of VGCNFs properties in a C/C composite. The specific objectives of the research are; (a) To understand the mechanical properties and microstructural features of phenolic resin precursor with and without modification with VGCNFs; (b) To develop innovative processing concepts that incorporate VGCNFs by spraying them on carbon fabric and/or adding VGCNFs to the phenolic resin precursor; and characterizing the process induced thermal and mechanical properties; and (c) To develop a finite element model to evaluate the thermal stresses developed in the carbonization of carbon/phenolic with and without VGCNFs. Addition of VGCNFs to phenolic resin enhanced the thermal and physical properties in terms of flexure and interlaminar properties, storage modulus and glass transition temperature and lowered the coefficient of thermal expansion. The approaches of spraying VGCNFs on the fabric surface and mixing VGCNFs with the phenolic resin was found to be effective in enhancing mechanical and thermal properties of the resulting C/C composites. Fiber bridging, improved carbon yield and minimization of carbonization-induced damage were the benefits of incorporating VGCNFs in C/C composites. Carbonization induced matrix cracking predicted by the finite element model is consistent with that observed experimentally. The finite element model is supported by a modification of a shear-lag model that describes the load transfer of a crack at the fiber/matrix interface.

Samalot Rivera, Francis J.

479

Process for making hollow carbon spheres  

DOEpatents

A hollow carbon sphere having a carbon shell and an inner core is disclosed. The hollow carbon sphere has a total volume that is equal to a volume of the carbon shell plus an inner free volume within the carbon shell. The inner free volume is at least 25% of the total volume. In some instances, a nominal diameter of the hollow carbon sphere is between 10 and 180 nanometers.

Luhrs, Claudia C.; Phillips, Jonathan; Richard, Monique N.; Knapp, Angela Michelle

2013-04-16

480

Forests as carbon sinks  

SciTech Connect

When the nations of the world signed and later ratified the United Nations Framework Convention on Climate Change (FCCC), they accepted the difficult challenge of stabilizing the composition of the atmosphere with respect to the greenhouse gases (GHGs). Success will require a reduction in both use of fossil fuels and rates of deforestation. Forests have a large enough influence on the atmosphere that one of the options for stabilizing the concentrations of GHGs in the atmosphere includes the use of forests as a carbon sink through reforestation of large areas. We identify in this paper the potential and the limitations of such projects. We discuss the implications of four approaches in management of forests globally: (i) continued deforestation, (ii) halting deforestation, (iii) net reforestation including agroforestry, and (iv) substituting the use of wood fuels for fossil fuels.

Houghton, R.A.; Woodwell, R.M. [Woods Hole Research Center, Woods Hole, MA (United States)

1995-11-01

481

Functionalization of Carbon Nanotubes  

NASA Technical Reports Server (NTRS)

Method and system for functionalizing a collection of carbon nanotubes (CNTs). A selected precursor gas (e.g., H2 or F2 or CnHm) is irradiated to provide a cold plasma of selected target species particles, such as atomic H or F, in a first chamber. The target species particles are d irected toward an array of CNTs located in a second chamber while suppressing transport of ultraviolet radiation to the second chamber. A CNT array is functionalized with the target species particles, at or below room temperature, to a point of saturation, in an exposure time interval no longer than about 30 sec. *Discrimination against non-target species is provided by (i) use of a target species having a lifetime that is much greater than a lifetime of a non-target species and/or (2) use of an applied magnetic field to discriminate between charged particle trajectories for target species and for non-target species.

Khare, Bishun N. (Inventor); Meyyappan, Meyya (Inventor)

2009-01-01

482

Dispersible carbon nanotubes.  

PubMed

A method is proposed to produce nanoparticles dispersible and recyclable in any class of solvents, and the concept is illustrated with the carbon nanotubes. Classically, dispersions of CNTs can be achieved through steric stabilization induced by adsorbed or grafted polymer chains. Yet, the surface modification of CNTs surfaces is irreversible, and the chemical nature of the polymer chains imposes the range of solvents in which CNTs can be dispersed. To address this limitation, supramolecular bonds can be used to attach and to detach polymer chains from the surface of CNTs. The reversibility of supramolecular bonds offers an easy way to recycle CNTs as well as the possibility to disperse the same functional CNTs in any type of solvent, by simply adapting the chemical nature of the stabilizing chains to the dispersing medium. The concept of supramolecular functionalization can be applied to other particles, for example, silica or metal oxides, as well as to dispersing in polymer melts, films or coatings. PMID:24458908

Soulié-Ziakovic, Corinne; Nicolaÿ, Renaud; Prevoteau, Alexandre; Leibler, Ludwik

2014-01-27

483

Cantilevered carbon nanotube hygrometer  

NASA Astrophysics Data System (ADS)

We investigate the effects of humidity on the vibrations of carbon nanotubes (CNTs) using two types of CNT cantilevers: open-ended and close-ended CNT cantilevers. As the humidity increases, the resonant frequency of the open-ended CNT cantilever decreases due to the adsorption of water molecules onto the CNT tip, whereas that of the close-ended CNT cantilever increases probably due to the change in the viscosity of the air surrounding the CNT cantilever, which is negatively correlated with the humidity of air. Our findings suggest that a close-ended CNT cantilever is more suitable for a quick-response and ultrasensitive hygrometer because it continuously reads the viscosity change of moist air in the vicinity of the CNT.

Kuroyanagi, Toshinori; Terada, Yuki; Takei, Kuniharu; Akita, Seiji; Arie, Takayuki

2014-05-01

484

Carbon nanotube Archimedes screws.  

PubMed

Recently, nanomechanical devices composed of a long stationary inner carbon nanotube and a shorter, slowly rotating outer tube have been fabricated. In this paper, we study the possibility of using such devices as nanoscale transducers of motion into electricity. When the outer tube is chiral, we show that such devices act like quantum Archimedes screws, which utilize mechanical energy to pump electrons between reservoirs. We calculate the pumped charge from one end of the inner tube to the other, driven by the rotation of a chiral outer nanotube. We show that the pumped charge can be greater than one electron per 360° rotation, and consequently, such a device operating with a rotational frequency of 10 MHz, for example, would deliver a current of ?1 pAmp. PMID:21126086

Oroszlány, László; Zólyomi, Viktor; Lambert, Colin J

2010-12-28

485

Carbon nanotube biconvex microcavities  

NASA Astrophysics Data System (ADS)

Developing highly efficient microcavities with predictive narrow-band resonance frequencies using the least amount of material will allow the applications in nonlinear photonic devices. We have developed a microcavity array that comprised multi-walled carbon nanotubes (MWCNT) organized in a biconvex pattern. The finite element model allowed designing microcavity arrays with predictive transmission properties and assessing the effects of the microarray geometry. The microcavity array demonstrated negative index and produced high Q factors. 2-3 ?m tall MWCNTs were patterned as biconvex microcavities, which were separated by 10 ?m in an array. The microcavity was iridescent and had optical control over the diffracted elliptical patterns with a far-field pattern, whose properties were predicted by the model. It is anticipated that the MWCNT biconvex microcavities will have implications for the development of highly efficient lenses, metamaterial antennas, and photonic circuits.

Butt, Haider; Yetisen, Ali K.; Ahmed, Rajib; Yun, Seok Hyun; Dai, Qing

2015-03-01

486

Carbon nanotube terahertz detector.  

PubMed

Terahertz (THz) technologies are promising for diverse areas such as medicine, bioengineering, astronomy, environmental monitoring, and communications. However, despite decades of worldwide efforts, the THz region of the electromagnetic spectrum still continues to be elusive for solid state technology. Here, we report on the development of a powerless, compact, broadband, flexible, large-area, and polarization-sensitive carbon nanotube THz detector that works at room temperature. The detector is sensitive throughout the entire range of the THz technology gap, with responsivities as high as ?2.5 V/W and polarization ratios as high as ?5:1. Complete thermoelectric and opto-thermal characterization together unambiguously reveal the photothermoelectric origin of the THz photosignal, triggered by plasmonic absorption and collective antenna effects, and suggest that judicious design of thermal management and quantum engineering of Seebeck coefficients will lead to further enhancement of device performance. PMID:24875576

He, Xiaowei; Fujimura, Naoki; Lloyd, J Meagan; Erickson, Kristopher J; Talin, A Alec; Zhang, Qi; Gao, Weilu; Jiang, Qijia; Kawano, Yukio; Hauge, Robert H; Léonard, François; Kono, Junichiro

2014-07-01

487

Carbon Monoxide Sensor  

NASA Technical Reports Server (NTRS)

The fuel cell is a system which employs an electrochemical process to convert gases- J such as hydrogen and oxygen directly into electricity. Under NASA sponsorship, GE's Aircraft Equipment Division developed fuel cells to supply electrical power for the Gemini and Biosatellite spacecraft of the sixties and is currently working on advanced fuel cell development. This long-term effort has resulted in a series of spinoff applications using the same general technology for a variety of purposes, among them the recently marketed Dosimeter. The Dosimeter is designed to help users meet safety requirements for industrial atmospheres, as specified by the Occupational Safety and Health Administration and other regulatory agencies. The compact, pocket-sized sensor measures personnel exposure to carbon monoxide and provides both a visual and an audible alarm if the concentration of the gas exceeds present levels. The Dosimeter offers substantial improvement in measuring accuracy over earlier warning indicators.

1978-01-01

488

Sampling Carbon Dioxide  

NSDL National Science Digital Library

In this lab activity, student teams hypothesize which source has a greater becomes CO² concentration: their breath, auto exhaust, or air in the classroom. They test gas samples from each of these sources, plot data, and hypothesize about the respective role engine exhaust and animal respiration play in contemporary climate change. The lab procedures require Bromthymol Blue indicator solution (BTB), household ammonia, vinegar, and balloons. Links to videos supporting the investigations are provided. This activity is supported by a textbook chapter, "How is Carbon Dioxide Measured?," part of the unit, Climate Change, in Global Systems Science (GSS), an interdisciplinary course for high school students that emphasizes how scientists from a wide variety of fields work together to understand significant problems of global impact.

2012-09-28

489

Carbon Nanotube Electron Gun  

NASA Technical Reports Server (NTRS)

An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

Nguyen, Cattien V. (Inventor); Ribaya, Bryan P. (Inventor)

2013-01-01

490

Carbon nanotube electron gun  

NASA Technical Reports Server (NTRS)

An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

Nguyen, Cattien V. (Inventor); Ribaya, Bryan P. (Inventor)

2010-01-01

491

Carbon Dioxide Landscape  

NASA Technical Reports Server (NTRS)

7 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mid-summer view of the south polar residual cap at full MOC resolution, 1.5 m (5 ft) per pixel. During each of the three summers since the start of the MGS mapping mission in March 1999, the scarps that form mesas and pits in the 'Swiss cheese'-like south polar terrain have retreated an average of about 3 meters (1 yard). The material is frozen carbon dioxide; another 3 meters or so of each scarp is expected to be removed during the next summer, in late 2005. This image is located near 86.0oS, 350.8oW, and covers an area about 1.5 km (0.9 mi) wide. Sunlight illuminates the scene from the top/upper left.

2004-01-01

492

Catalytic Growth of Macroscopic Carbon Nanofibers Bodies with Activated Carbon  

SciTech Connect

Carbon-carbon composite of activated carbon and carbon nanofibers have been synthesized by growing Carbon nanofiber (CNF) on Palm shell-based Activated carbon (AC) with Ni catalyst. The composites are in an agglomerated shape due to the entanglement of the defective CNF between the AC particles forming a macroscopic body. The macroscopic size will allow the composite to be used as a stabile catalyst support and liquid adsorbent. The preparation of CNT/AC nanocarbon was initiated by pre-treating the activated carbon with nitric acid, followed by impregnation of 1 wt% loading of nickel (II) nitrate solutions in acetone. The catalyst precursor was calcined and reduced at 300 deg. C for an hour in each step. The catalytic growth of nanocarbon in C{sub 2}H{sub 4}/H{sub 2} was carried out at temperature of 550 deg. C for 2 hrs with different rotating angle in the fluidization system. SEM and N{sub 2} isotherms show the level of agglomeration which is a function of growth density and fluidization of the system. The effect of fluidization by rotating the reactor during growth with different speed give a significant impact on the agglomeration of the final CNF/AC composite and thus the amount of CNFs produced. The macrostructure body produced in this work of CNF/AC composite will have advantages in the adsorbent and catalyst support application, due to the mechanical and chemical properties of the material.

Abdullah, N.; Muhammad, I. S.; Hamid, S. B. Abd. [NANOCEN, Block A, Level 3, Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur (Malaysia); Rinaldi, A. [NANOCEN, Block A, Level 3, Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur (Malaysia); Inorganic Chemistry Department, Fritz-Haber Institute der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany); Su, D. S.; Schlogl, R. [Inorganic Chemistry Department, Fritz-Haber Institute der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany)

2009-06-01

493

The reionization of carbon  

NASA Astrophysics Data System (ADS)

Observations suggest that C II was more abundant than C IV in the intergalactic medium towards the end of the hydrogen reionization epoch (z ˜ 6). This transition provides a unique opportunity to study the enrichment history of intergalactic gas and the growth of the ionizing ultraviolet background (UVB) at early times. We study how carbon absorption evolves from z = 10 to 5 using a cosmological hydrodynamic simulation that includes a self-consistent multifrequency UVB as well as a well-constrained model for galactic outflows to disperse metals. Our predicted UVB is within ˜2-4 times of that from Haardt & Madau, which is fair agreement given the uncertainties. Nonetheless, we use a calibration in post-processing to account for Lyman ? forest measurements while preserving the predicted spectral slope and inhomogeneity. The UVB fluctuates spatially in such a way that it always exceeds the volume average in regions where metals are found. This implies both that a spatially uniform UVB is a poor approximation and that metal absorption is not sensitive to the epoch when H II regions overlap globally even at column densities of 1012 cm-2. We find, consistent with observations, that the C II mass fraction drops to low redshift while C IV rises owing the combined effects of a growing UVB and continued addition of carbon in low-density regions. This is mimicked in absorption statistics, which broadly agree with observations at z = 6-3 while predicting that the absorber column density distributions rise steeply to the lowest observable columns. Our model reproduces the large observed scatter in the number of low-ionization absorbers per sightline, implying that the scatter does not indicate a partially neutral Universe at z ˜ 6.

Finlator, Kristian; Thompson, Robert; Huang, Shuiyao; Davé, Romeel; Zackrisson, E.; Oppenheimer, B. D.

2015-03-01

494

UCSF Sustainability Baseline Assessment: Carbon Footprint Analysis  

E-print Network

UCSF Sustainability Baseline Assessment: Carbon Footprint Analysis Final Issue Date: March 21, 2010 #12;Carbon Footprint Analysis Background This chapter of the Sustainability Assessment focuses on UCSF

Yamamoto, Keith

495

The evolution of carbon stars  

NASA Astrophysics Data System (ADS)

This thesis is concerned with the evolution of carbon stars. A carbon star is a late-type star in which the abundance of carbon in the photosphere is greater than that of oxygen. Data from the Infrared Astronomical Satellite (IRAS) survey were used to show that carbon stars which are identified from optical surveys and those identified from the SiC dust features in the IRAS Low Resolution Spectrometer (LRS) spectra have different IRAS colors. The former ( "visual carbon stars" ) are visually bright and have large excesses at 60 mu m, while the latter group ( "infrared carbon stars" ) have blackbody energy distributions. All catalogued visual carbon stars with IRAS 12 mu m fluxes greater than 5 Jy were searched for LRS spectra in the IRAS LRS data base. 152 new LRS spectra with reasonable good signal-to-noise ratio along with 575 sources with previously released LRS spectra have been classified in the classification scheme of Volk and Cohen (1989a). The LRS spectra of all these sources were examined, and 15 were found to show the 10 mu m silicate emission feature. Eight of these are new discoveries. This group of "silicate carbon stars" may represent transition objects between oxygen-rich and carbon stars on the asymptotic giant branch (AGB). A radiative transfer model of optically thick detached shells for these silicate carbon stars is presented which produces excellent fits to the observed energy distribution of silicate carbon stars. J stars (l3C-rich carbon stars) have been suggested to be transition objects between M-type stars and C-type stars. An optical spectroscopic study of these silicate carbon stars was performed. Four sources have been confirmed to be J stars. Two more are provisionally identified as J stars. A preliminary spectral analysis has also been carried out. Model calculations are presented on the evolution from the visual carbon stars to infrared carbon stars, and on the evolution of infrared carbon stars. A new empirical opacity function for the SiC grain is derived from the LRS spectra of infrared carbon stars. A two-shell system model (oxygen-rich detached shell and newly-forming SiC dust shell), the Interrupted Mass Loss Model, has been developed. The energy distribution of approximately 110 transition objects with developing SiC dust shells are fitted with the Interrupted Mass Loss Model. Furthermore, the model tracks successfully explain the 'C' shaped distribution of these objects in the IRAS 12 mu m/25 mu m/60 mu m colour-colour diagram. The energy distributions of approximately 150 infrared carbon stars are also matched with a radiative transfer SiC dust shell model. The evolution of infrared carbon stars (from the SiC shell model) can be understood by a continuous increase in mass loss rate on the AGB. A evolutionary scenario of AGB stars is suggested. There is a branching of M-type and C-type stars on the AGB with each branch evolving independently to the planetary nebula stage. The initial mass of the star in the main sequence may be the factor that determines which branch the star will follow.

Chan, Siu-Kuen Josephine

1992-01-01

496

Carbon sequestration in European croplands.  

PubMed

The Marrakech Accords allow biospheric carbon sinks and sources to be included in attempts to meet emission reduction targets for the first commitment period of the Kyoto Protocol. Forest management, cropland management, grazing land management, and re-vegetation are allowable activities under Article 3.4 of the Kyoto Protocol. Soil carbon sinks (and sources) can, therefore, be included under these activities. Croplands are estimated to be the largest biospheric source of carbon lost to the atmosphere in Europe each year, but the cropland estimate is the most uncertain among all land-use types. It is estimated that European croplands (for Europe as far east as the Urals) lose 300 Tg (C) per year, with the mean figure for the European Union estimated to be 78 Tg (C) per year (with one SD=37). National estimates for EU countries are of a similar order of magnitude on a per-area basis. There is significant potential within Europe to decrease the flux of carbon to the atmosphere from cropland, and for cropland management to sequester soil carbon, relative to the amount of carbon stored in cropland soils at present. The biological potential for carbon storage in European (EU 15) cropland is of the order of 90-120 Tg (C) per year, with a range of options available that include reduced and zero tillage, set-aside, perennial crops, deep rooting crops, more efficient use of organic amendments (animal manure, sewage sludge, cereal straw, compost), improved rotations, irrigation, bioenergy crops, extensification, organic farming, and conversion of arable land to grassland or woodland. The sequestration potential, considering only constraints on land use, amounts of raw materials and available land, is up to 45 Tg (C) per year. The realistic potential and the conservative achievable potentials may be considerably lower than the biological potential because of socioeconomic and other constraints, with a realistically achievable potential estimated to be about 20% of the biological potential. As with other carbon sequestration options, potential impacts of non-CO, trace gases also need to be factored in. If carbon sequestration in croplands is to be used in helping to meet emission reduction targets for the first commitment period of the Kyoto Protocol, the changes in soil carbon must be measurable and verifiable. Changes in soil carbon can be difficult to measure over a 5-year commitment period, and this has implications for Kyoto accounting and verification. Currently, most countries can hope to achieve only a low level of verifiability during the first commitment period, whereas those with the best-developed national carbon accounting systems will be able to deliver an intermediate level of verifiability. Very stringent definitions of verifiability would require verification that would be prohibitively expensive for any country. There is considerable potential in European croplands to reduce carbon fluxes to the atmosphere and to sequester carbon iri the soil, but carbon sequestration in soil has a finite potential and is non-permanent. Given that carbon sequestration may also be difficult to measure and verify, soil carbon sequestration is a riskier long-term strategy for climate mitigation than direct reduction of carbon emissions. However, improved agricultural management often has a range of other environmental and economic benefits in addition to climate mitigation potential, and this may make attempts to improve soil carbon storage attractive as part of integrated sustainability policies. PMID:17633030

Smith, Pete; Falloon, Pete

2005-01-01

497

A 400 million year carbon isotope record of pedogenic carbonate: Implications for paleoatmospheric carbon dioxide  

Microsoft Academic Search

A 400 record of atmospheric carbon dioxide levels has been estimated by applying a COâ paleobarometer to a database of 758 analyses of paleosol (fossil soil) carbonates. This database is a compilation of new data and previously published values from the literature. Many new analyses of Mesozoic paleosols are reported, an era poorly represented in the literature. Results indicate that

D. D. Ekart; T. E. Cerling; I. P. Montanez; N. J. Tabor

1999-01-01

498

Nanophase Carbonates on Mars: Implications for Carbonate Formation and Habitability  

NASA Technical Reports Server (NTRS)

Despite having an atmosphere composed primarily of CO2 and evidence for abundant water in the past, carbonate minerals have only been discovered in small amounts in martian dust [1], in outcrops of very limited extent [2, 3], in soils in the Northern Plains (the landing site of the 2007 Phoenix Mars Scout Mission) [4] and may have recently been detected in aeolian material and drilled and powdered sedimentary rock in Gale Crater (the Mars Science Laboratory [MSL] landing site) [5]. Thermal analysis of martian soils by instruments on Phoenix and MSL has demonstrated a release of CO2 at temperatures as low as 250-300 degC, much lower than the traditional decomposition temperatures of calcium or magnesium carbonates. Thermal decomposition temperature can depend on a number of factors such as instrument pressure and ramp rate, and sample particle size [6]. However, if the CO2 released at low temperatures is from carbonates, small particle size is the only effect that could have such a large impact on decomposition temperature, implying the presence of extremely fine-grained (i.e., "nanophase" or clay-sized) carbonates. We hypothesize that this lower temperature release is the signature of small particle-sized (clay-sized) carbonates formed by the weathering of primary minerals in dust or soils through interactions with atmospheric water and carbon dioxide and that this process may persist under current martian conditions. Preliminary work has shown that clay-sized carbonate grains can decompose at much lower temperatures than previously thought. The first work took carbonate, decomposed it to CaO, then flowed CO2 over these samples held at temperatures >100 degC to reform carbonates. Thermal analysis confirmed that carbonates were indeed formed and transmission electron microsopy was used to determine crystal sized were on the order of 10 nm. The next step used minerals such as diopside and wollastonite that were sealed in a glass tube with a CO2 and H2O source. After reacting these materials for a number of hours, thermal analysis demonstrated the formations of carbonates that decomposed at temperatures as low as 500 degC [7]. Further work is underway to carry out the weathering process under more Mars-like conditions (low pressure and low temperature) to determine if the carbonate decomposition temperature can be shifted to even lower temperatures, consistent with what has been detected by thermal analysis instruments on Mars.

Archer, P. Douglas, Jr.; Lauer, H. Vern; Ming, Douglas W.; Niles, Paul B.; Morris, Richard V.; Rampe, Elizabeth B.; Sutter, Brad

2014-01-01

499

Spectral evidence for carbonates on Mars: Hydrous carbonates  

NASA Technical Reports Server (NTRS)

Although many of the spectral features of the Martian samples studied are not unique mineralogical indicators, much of the current spectral data is consistent with (possibly abundant) hydrous carbonates on the surface of Mars. The absorption features in the measured samples were quite weak compared with those of anhydrous carbonates. The weak features imply that significantly more hydrous carbonates can be incorporated onto the surface before becoming spectrally evident; however, exact limits have yet to be determined. The stability of these materials in the Martian environment is not known, but their formation and occurrence in low temperature terrestrial environments makes them appealing candidates for weathering products on Mars.

Calvin, W. M.; King, T. V. V.

1991-01-01

500

Onion-like carbon and carbon nanotube film antennas  

NASA Astrophysics Data System (ADS)

In this paper, radiating dipole antennas have been fabricated from rolled carbon films, which are typically used for supercapacitor electrodes. Return loss and radiation pattern measurements for onion-like carbon (OLC) and multi-walled carbon nanotubes (MWCNTs) antenna samples are presented and compared to a copper standard. The OLC antenna's radiation pattern measurements show a peak gain of -1.48 dBi, just less than 3 dB of a copper dipole antenna. Compared to antennas made from MWCNT films, the OLC samples show better radiation performance despite a lower measured conductivity.

Vacirca, Nicholas A.; McDonough, John K.; Jost, Kristy; Gogotsi, Yury; Kurzweg, Timothy P.

2013-08-01