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carbonaceous chondrite Although fewer than 100 carbonaceous chondrites are known, they provide a great deal of information about the origin of the Sun and planets, and even of life itself (see organic matter, in meteorites). Carbonaceous chondrites are the most primitive and unaltered type of meteorite known, with an elemental composition probably similar to that of the nebula Different groups of carbonaceous chondrites have been identified that came from parent bodies in different parts of the solar nebula. www.daviddarling.info /encyclopedia/C/carbchon.html   (1078 words)

Encyclopedia: Carbonaceous chondrite   (Site not responding. Last check: 2007-11-07) Carbonaceous chondrites are the most primitive and unaltered type of meteorite known, with an elemental composition probably similar to that of the nebula from which the Solar System formed. All carbonaceous chondrites are primitive and undifferentiated meteorites that formed in oxygen-rich regions of the primordial solar nebula so that most of the metal is not found in its free form but in the form of silicates, oxides, or sulfides. However, the carbonaceous chondrites are a rather heterogenous class, and there are different clans and groups of carbonaceous chondrites that formed on their respective parent bodies in different regions of the early solar nebula. www.nationmaster.com /encyclopedia/Carbonaceous-chondrite   (1023 words)

Carbonaceous chondrite - Wikipedia, the free encyclopedia A carbonaceous chondrite or a C-type chondrite is a type of chondritic meteorite which contains high levels of water and organic compounds, representing only a small proportion (~5%) of known meteorites. Carbonaceous chondrites are grouped according to dinstinctive compositions thought to reflect the type of parent body from which they originated. This group, named after the Ivuna meteorite, are considered the least altered of all carbonaceous chondrites. en.wikipedia.org /wiki/Carbonaceous_chondrite   (416 words)

Carbonaceous - Wikipedia, the free encyclopedia Please categorize this article to list it with similar topics. Carbonaceous is the defining attribute of a substance rich in carbon. Particularly, carbonaceous hydrocarbons are very unsaturated, high-molecular-weight hydrocarbons, having an elevated carbon:hydrogen ratio. en.wikipedia.org /wiki/Carbonaceous   (86 words)

[No title] Carbonaceous (C) chondrites are some of the most complex of all meteorites. Carbonaceous chondrites are the only meteorites known with petrologic grades 1 and 2. Two carbonaceous chondrites, Allende and Murchison, are of particular interest to scientists and, curiously, both fell in 1969, but on opposite sides of the world. www.meteorlab.com /METEORLAB2001dev/carbchon.htm   (289 words)

Flame retardant foams - Patent 4857394 It is understood that when the lower amounts of the carbonaceous fibers are being utilized, that is 0.5%, the carbonaceous fiber is intended to be primarily on the surface of the foam structure. It has been surprisingly discovered that when carbonaceous fibers, especially non-linear fibers, are added to the reaction mixture of a foam forming reaction, a substantial portion of the carbonaceous fibers will bcome distributed on the exterior surface of the formed structure when the reaction mixture is not stirred. The carbonaceous material which may be utilized in the invention may be derived from stabilized acrylic fibers which are classified into three groups depending upon the particular use and the environment that the structures in which they are incorporated are placed. www.freepatentsonline.com /4857394.html   (3833 words)

Carbonaceous Clues to the Early Solar System   (Site not responding. Last check: 2007-11-07) Scientists have conducted an organic analysis of the Tagish Lake meteorite, a rare, carbon-rich meteorite classified as a carbonaceous chondrite. For example, the Murchison meteorite, a carbonaceous chondrite found in Australia in 1969, contains numerous amino acids and a variety of other organic compounds that are the building blocks for life. Carbonaceous chondrite meteorites generally show little evidence of being shaped by high temperatures. nai.arc.nasa.gov /news_stories/tagish.cfm   (927 words)

Natural Petroleum - NO Connection With Biological Matter The carbonaceous meteorites, including particularly the carbonaceous chondrites, are meteorites whose chemical composition includes carbon in quantities ranging from a few tenths of a percent to approximately six percent, by mass.1-5 The age of the carbonaceous meteorites is typically 3-4.5 billion years; and their origins clearly abiotic. Significantly, much of the carbon material of the carbonaceous meteorites consists of hydrocarbons, as both solids and in liquid form.1, 5, 7, 8 However, the petroleum material contained in carbonaceous meteorites cannot be considered to be the origin of the natural petroleum found in the near-surface crust of the Earth. From the interiors of carbonaceous meteorites have been extracted the common amino-acid molecules alanine, aspartic acid, glutamic acid, glycine, leusine, proline, serine, threonine, as well as the unusual ones a-aminoisobutyric acid, isovaline, pseudoleucine.22-24 At one time, all had been considered to be solely of biotic origin. www.rense.com /general65/naty.htm   (4493 words)

[No title]   (Site not responding. Last check: 2007-11-07) A second approach for increasing the catalytic activity of carbonaceous chars begins with a carbonaceous feedstock which is inherently suitable to yield a high degree of catalytic activity in the final carbonaceous chars. Oxidation of said treated carbonaceous feedstock can be effected during or after carbonization and is optionally conducted to a level that is typically well beyond the requirements of activated carbon manufacture. In another preferred embodiment of the invention, the carbonaceous material is a coal to which less than 15% by weight of a nitrogen-containing compound having at least one nitrogen functionality in which the nitrogen exhibits an oxidation number of less than zero is added. www.wipo.int /cgi-pct/guest/getbykey5?KEY=01/05704.010125&ELEMENT_SET=DECL   (6231 words)

Fluorinated carbonaceous fibers - Patent 4937140 The linear carbonaceous fibers may be prepared by heat treating fibers or filaments in a manner known in the art. The carbonaceous materials which are utilized in the present invention may be classified in three groups depending upon the particular use and the environment that the structures in which they are incorporated are placed. The carbonaceous aromatic polyamide fibers and fibrous materials which may be utilized in the fluorination treatment according to the invention may be prepared according to the process described in the aforementioned U.S. Pat. www.freepatentsonline.com /4937140.html   (2500 words)

Carbonaceous adsorbent regeneration and halocarbon displacement by hydrocarbon gases - Patent 5300468 Carbonaceous adsorbent regeneration and halocarbon displacement by hydrocarbon gases This invention describes a process for regeneration of halocarbon bearing carbonaceous adsorbents through which a carbonaceous adsorbent is contacted with hydrocarbon gases, preferably propane, butane and pentane at near room temperatures and at atmospheric pressure. Carbonaceous adsorbents are used routinely for the adsorption of halocarbons from gaseous and aqueous streams as used in air and water purification processes. www.freepatentsonline.com /5300468.html   (4643 words)

www.meteorites.com classification   (Site not responding. Last check: 2007-11-07) Carbonaceous chondrites have mostly undergone aqueous alteration (none are of grade higher than 4), while most ordinary and enstatite chondrites have undergone thermal metamorphism (none are of grade lower than 3). Carbonaceous chondrites are further subdivided into four subgroups, in two different ways: 1) with respect to elemental composition; b) by petrologic type. In the second subdivision scheme, the carbonaceous chondrites are classified on a petrological (as opposed to compositional) basis more specifically according to their state of alteration. www.meteorites.com /classif.html   (3318 words)

[No title]   (Site not responding. Last check: 2007-11-07) Claim 27-A fuel for barbecuing, comprising: a carbonaceous material, said carbonaceous material having a shape which is a cylinder including a plan view which is a circle and a circumscribing sidewall, and having flattened surfaces on the sidewall of said cylinder defined by a plurality of planes cutting through chords of said circle. Claim 31-A fuel for barbecuing, comprising in combination: a carbonaceous material having a surface, an accelerant, said accelerant disposed on a portion of said surface of said carbonaceous material, and fusing means, said fusing means disposed on said surface of said carbonaceous material coincidental with said accelerant. a carbonaceous material, said carbonaceous material having a shape which is a cylinder including a cross-section which is a circle and a circumscribing sidewall, and having flattened surfaces on said sidewall defined by a plurality of planes cutting through chords of said circle. www.wipo.int /cgi-pct/guest/getbykey5?KEY=03/66786.030814&ELEMENT_SET=DECL   (5751 words)

Carbonaceous-Silicate Grain Models The model consists of a mixture of carbonaceous grains and silicate grains, each with a broad size distribution extending from a = 3.5 Angstrom ultrasmall grains (containing tens of C atoms) to micron-sized particles. The smallest carbonaceous grains have the optical and physical properties of PAH (polycyclic aromatic hydrocarbon) molecules. The larger (a > 100 Angstrom) carbonaceous grains are assumed to have the optical properties of graphite spheres. www.astro.princeton.edu /~draine/dust/dustmix.html   (753 words)

THE SIGNIFICANCE OF PROTEIN AMINO ACIDS IN CARBONACEOUS METEORITES   (Site not responding. Last check: 2007-11-07) However, given the preponderance of impact events during the Earth's early history and the fact that carbonaceous meteorites contain amino acids, the exogenous delivery of life's precursors to Earth is a reasonable alternative. Carbonaceous meteorites contain eight of the protein amino acids that, with the exception of glycine, exhibit the L-enantiomer excess that is characteristic of life. It is possible that most of these amino acids were also present in carbonaceous meteorites, but diagenetic processes and analytical uncertainties have effectively limited their detection. gsa.confex.com /gsa/2003AM/finalprogram/abstract_59831.htm   (378 words)

Allende Meteorite Carbonaceous chondrites are thought to be the most primitive form of matter in the universe. CI carbonaceous chondrites--a somewhat more primitive type--have a composition very close to that of the Sun. Chemical analyses of carbonaceous chondrites have revealed both non-biological and biological amino acids--the buildings blocks of life. www.alaska.net /~meteor/AMinfo.htm   (693 words)

CO3, CR, CM, CV, CK, CI, CH, carbonaceous chondrites Carbonaceous chondrites are a rare kind of meteorite that contain organic compounds such as amino acids and kerogin, an organic matter often found in coal and shale. Instead of containing the anhydrous silicates found in most chondrites, the carbonaceous types have claylike hydrous silicate minerals. Carbonaceous chondrites represent some of the most primitive of all meteorites, with solar major element composition (Fe, Si, Mg, Ca, Al). www.saharamet.com /meteorite/gallery/Ctypes/CAIs.html   (417 words)

Carbonaceous Chondrite   (Site not responding. Last check: 2007-11-07) Carbonaceous chondrite is any stony meteorite or asteroid containing material associated with life (e.g., hydrocarbons, amino acids, and forms resembling microscopic fossils) and for which some researchers have postulated an extraterrestrial biological origin. Magnesium sulfate is found in narrow veins; and since it is water soluble, carbonaceous chondrites disintegrate rapidly because of weathering. Their texture, similar to that of the terrestrial rocks called volcanic tuffs, indicates that they have been repeatedly fragmented and re-cemented. abyss.uoregon.edu /~js/glossary/carbonaceous_chondrite.html   (118 words)

Research Abstract: 1987-01 Intercomparison Of Methods For The Measurement Of Carbonaceous Aerosol Species The denuder was intended to prevent sorption of vapor-phase carbonaceous material on the quartz filter, particulate matter thereon, or the fluidized bed. The fluidized bed was intended to trap carbonaceous material lost from the filter by volatilization following collection in the particulate state. Based on QA studies as well as atmospheric particulate sample results, the alumina denuder was judged ineffective in eliminating the positive error in organic aerosol sampling with quartz filters. www.arb.ca.gov /research/abstracts/a4-158-32.htm   (492 words)

Carbonaceous ores Carbonaceous ores are those containing components which absorb dissolved gold during leaching thereby reducing gold extractions by cyanidation. Carbonaceous matter is also present in Witwatersrand ores (sometimes called Thucholite) though it contributes only a small extent to reduced gold extraction. Such carbonaceous matter consists of hydrocarbon, humic acid and elemental carbon. www.e-goldprospecting.com /html/carbonaceous_ores.html   (200 words)

Carbonaceous megaremains from the Neoproterozoic Owk Shales On the basis of the present fossil assemblage, the OSF is considered to be of the Neoproterozoic age. The carbonaceous compression and impressions reported here are found in abundance on bedding planes at the shale-siltstone, and shale-claystone junctions of the OSF. The OSF specimens are small pieces of carbonaceous remains and similar to the type material. www.ias.ac.in /currsci/may10/articles24.htm   (2388 words)

EPA: ORD: NCER: Research Opportunities: Current RFA Thus, the focus of this RFA is on carbonaceous PM2.5, which is expected to be a significant contributor to PM2.5 in areas that are predicted to continue to violate the NAAQS. Carbonaceous PM is composed of two major components: organic carbon, which is made up of hundreds of individual organic compounds, and elemental carbon, which is also referred to as soot, fl carbon, or light-adsorbing carbon. When available, organic tracer species of carbonaceous PM2.5 are a powerful means to match source signatures with ambient measurements to determine the relative importance of emission sources (e.g., Schauer et al., 1996). es.epa.gov /ncer/rfa/current/2003airpm.html   (3062 words)

Factors of Metamorphism of Carbonaceous Material   (Site not responding. Last check: 2007-11-07) Metamorphism of the carbonaceous material is expressed in the graphitisation process. Retention of the volatile matter may also be responsible for the required plasticity to yield the mesophase habit of the transitional material. It depends strongly on temperature and to lesser extent on static pressure, shear stress, coexisting minerals that act as catalysts and the type of carbonaceous material. titan.minpet.unibas.ch /minpet/persons/petrova/factor.html   (504 words)

Class Definition for Class 201 - DISTILLATION: PROCESSES, THERMOLYTIC Solid carbonaceous materials within the purview of this class (201) include (exemplary but not limiting) such minerals as coal and oil shale and substances of an organic nature such as organic wastes and wood. The term is also applied in the art to the solid, carbonaceous residue from the thermolytic distillation of such materials as oil shale, petroleum and pitch. For the purpose of this class is the carbonaceous material which is undergoing a distillation operation. www.uspto.gov /go/classification/uspc201/defs201.htm   (4338 words)

ARS | Publication request: Carbonaceous Materials in Soil-Derived Dusts Soil-derived carbon-rich material exists in many organic and inorganic forms in soils including but not limited to living organisms, remains of organisms or chemicals that they create in various stages of decomposition including relatively stable forms such as humus, sorbed man-made chemicals such as pesticides, herbicides, and incidental contaminants, charcoal, and carbonate minerals. This carbonaceous portion of soils material that is lost due to wind erosion is the most chemically active portion of the soil and perhaps the most important. A large body of literature deals with carbonaceous aerosols of anthropogenic and other non-soil related sources such as industry, combustion, volatile organic materials released from vegetation, etc., and natural geological emissions. www.ars.usda.gov /research/publications/publications.htm?SEQ_NO_115=104506&pf=1   (415 words)

Method and apparatus for a vacuum thermionic converter with thin film carbonaceous field emission (US6064137) A Vacuum Diode is constructed in which the electrodes of the Vacuum Diode are coated with a thin film of diamond-like carbonaceous material. The cathode and anode are separated by spacers and a rinse-able material, the rinse-able material which is later removed. Carbonaceous films and the related process for producing a thin film of ablated diamond are not previously known in connection with Vacuum Thermionic Converters, and provide a practical and improved means of constructing such devices. www.delphion.com /details?pn=US06064137__   (413 words)

Carbonaceous Meteorites: Analogs for organic synthesis on Mars Carbonaceous Meteorites: Analogs for organic synthesis on Mars   Carbonaceous meteorites consist of material derived from the solar nebula 4.5 billion years ago.   In summary, carbonaceous meteorites collected at the time of or shortly after impact provide the most reliable record of the solar system’s organic inventory during the early stages of its formation. www.psi.edu /~rperry/perry/Marsabstract.html   (406 words)

Chapter 7.2 There are two stages of decomposition in the BOD test: a carbonaceous stage and a nitrogenous stage (fig. The carbonaceous stage, or first stage, represents that portion of oxygen demand involved in the conversion of organic carbon to carbon dioxide. The nitrogenous stage, or second stage, represents a combined carbonaceous plus nitrogeneous demand, when organic nitrogen, ammonia, and nitrite are converted to nitrate. water.usgs.gov /owq/FieldManual/Chapter7-Archive/chapter7.2/7.2.html   (718 words)

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