(n.) Mineral pitch; a black, tarry substance, burning with a bright flame; Jew's pitch. It occurs as an abundant natural product in many places, as on the shores of the Dead and Caspian Seas. It is used in cements, in the construction of pavements, etc. See Asphalt.
(n.) By extension, any one of the natural hydrocarbons, including the hard, solid, brittle varieties called asphalt, the semisolid maltha and mineral tars, the oily petroleums, and even the light, volatile naphthas.
Example Sentences:
(1) Tar bitumens are classifiable as the pyrolysis products of organic materials and are applied hot.
(2) The tests of bitumen, chlorcaoutchouc, asbestos cement and polyacryl delivered results comparable to those achieved under working conditions.
(3) Did these donations have anything to do with the investigation found, Clinton’s State Department approving the Alberta Clipper , a controversial pipeline carrying large amounts of tar-sands bitumen from Alberta to Wisconsin?
(4) There is also oil company interest in shale deposits at 10 locations in Morocco, two in Egypt as well as a "bitumen belt" in Nigeria which is already suffering major environmental damage from oil spills in the delta and the flaring of excess gas.
(5) But the huge amounts of water and solvents needed to extract oil from bitumen dramatically boost greenhouse gas output and, on latest production forecasts, will increase Canada’s CO2 emissions by 56 megatonnes by 2020 .
(6) The primary task is to ascertain whether tar bitumen can be replaced as a binder in paving for roads and what safety measures are practicable.
(7) Even plastics and bitumen which were used in the sphere of drinking water showed after an exposure time of three months up to 192 ml slime per square meter.
(8) The acute toxicity of three materials derived from Athabasca Oil Sands--(1) bitumen plus naphtha, (2) untreated naphtha (0-250 degrees C) and (3) synthetic crude oil (0-500 degrees C)--was assessed in a battery of tests.
(9) The relation of carbohydrate and protein content significantly changed from 2 at the beginning to 30 after 12 months of incubation the bitumen coating test plates.
(10) Since the bitumen-derived streams do not differ substantially in carcinogenic potency from petroleum-derived materials of comparable boiling range and process history, industrial hygiene practices which limit exposures to levels comparable to those observed in the petroleum-refining industry should provide similar measures of protection.
(11) Biological monitoring of exposure to bitumen fumes during road-paving operations was carried out.
(12) The exposure of sixteen road workers to bitumen fumes was studied.
(13) Time-weighted average values of bitumen fumes were determined by personal samplers.
(14) Mineral water and bitumen fraction induced an increase of the enzyme activity by 23, 20 and 45%, respectively.
(15) Bitumen plus naphtha administered at a concentration of 1.46 mg l-1 did not cause mortality in exposed rats or mice.
(16) A 2010 analysis by Accufacts Inc., an energy consulting firm that focuses on pipelines, identified Koch's Corpus Christi plant as one of 22 Gulf Coast refineries—out of more than 50—that is now capable of refining "a significant volume of blended bitumen," the type of crude that would flow through the Keystone XL.
(17) The village's fishing creek is contaminated; the school has been looted; the mangrove forests are coated in bitumen and everyone has left, refugees from a place blighted by the exploitation of the region's most valuable asset: crude oil.
(18) If the oil finds its way into those waters, the heavy tar sands bitumen will create a submerged disaster requiring a cleanup effort far above and beyond conventional responses.
(19) The carcinogenic potential of Athabasca tar sands and six experimental liquids derived from crude bitumen was evaluated utilizing the mouse epidermal carcinogenesis model.
(20) In the laboratory technique they have been using the American PIN-DEX system of pull-out necks, modelling of buttress construction without relief and together with the construction, in addition to ceramic facet making to chemical facet-making by means of composite bitumen made by KULZER, trade mark DENTACOLOR XS, which polymerize in Ultraviolet light.
Naphtha
Definition:
(n.) The complex mixture of volatile, liquid, inflammable hydrocarbons, occurring naturally, and usually called crude petroleum, mineral oil, or rock oil. Specifically: That portion of the distillate obtained in the refinement of petroleum which is intermediate between the lighter gasoline and the heavier benzine, and has a specific gravity of about 0.7, -- used as a solvent for varnishes, as a carburetant, illuminant, etc.
(n.) One of several volatile inflammable liquids obtained by the distillation of certain carbonaceous materials and resembling the naphtha from petroleum; as, Boghead naphtha, from Boghead coal (obtained at Boghead, Scotland); crude naphtha, or light oil, from coal tar; wood naphtha, from wood, etc.
Example Sentences:
(1) Acute toxicity studies using rats and rabbits compared the effects of naphtha, Jet-A, JP-4, diesel and "residual" distillate fractions of both petroleum derived crude oils and hydrotreated shale oil.
(2) A program was initiated to assess the toxicological properties of high-flash aromatic naphtha since there may be human exposure through inhalation or external body contact.
(3) The acute toxicity of three materials derived from Athabasca Oil Sands--(1) bitumen plus naphtha, (2) untreated naphtha (0-250 degrees C) and (3) synthetic crude oil (0-500 degrees C)--was assessed in a battery of tests.
(4) Three toddlers mis-swallowed a mouth of cleaning naphtha accidentally.
(5) It is concluded that chronic exposure to this high aromatic naphtha is without systemic toxicity in rats under the conditions of these studies.
(6) Inhalation studies were conducted to assess the subacute and subchronic toxicity of EDS hydrotreated naphtha (HN).
(7) Bitumen plus naphtha administered at a concentration of 1.46 mg l-1 did not cause mortality in exposed rats or mice.
(8) There was little evidence that inhalation exposure to EDS hydrotreated naphtha adversely affected reproductive performance or fetal development in Sprague-Dawley rats.
(9) A unique opportunity was presented to observe the potentially toxic effects of an acute exposure to the vapors of petroleum naphtha distillate on a relatively large number of individuals.
(10) An amount of 5 g of naphtha or fuel oil is diluted to 10 ml with dichloromethane and spiked with a small quantity (ca.
(11) In addition, the nephrotoxic activity observed with the naphtha streams and distillation fraction correlated well with the proportion of branched alkanes contained in each.
(12) A synthetic crude oil, prepared by blending naphtha and light and heavy gas oils, was moderately carcinogenic; however, the activity of this sample fell within the range of values obtained in studies of crude petroleum samples.
(13) One such application is a mixture of predominantly 9-carbon aromatic molecules (C9 aromatics, primarily isomers of ethyltoluene and trimethylbenzene), which is removed and used as a solvent--high-flash aromatic naphtha.
(14) Industrial hygiene measurements showed low-level airborne exposures to organic solvents (primarily naphthas) and minimal airborne exposure to glycol ethers.
(15) One such application is a mixture of predominantly 9-carbon aromatic molecules (C9 aromatics, primarily isomers of ethyltoluene and trimethylbenzene), which is removed and used as a solvent--High Flash Aromatic Naphtha.
(16) 5-Isothiocyanato-1,3-dioxo-2-p-tolyl-2,3-dihydro-1H-benz[de]isoquinoline (= 5-isothio-cyanato-1,8-naphthalenedicarbox-4-methylphenylimide, compd.5) was synthesized from 1H,3H-naphtho(1,8-cd)pyran-1,3-dione (= 1,8-naphtha-lenedicarboxylic anhydride, compd.1) through nitration, condensation with p-toluidine, reduction with tin(II)-chloride yielding 5-amino-1,3-dioxo-2-p-tolyl-2,3-dihydro-1H-benz(de)isoquino-line (4) as intermediate, and condensation with thiophosgene.
(17) Untreated naphtha administered at a concentration of 10.6 mg l-1 was lethal to essentially all of the mice; but only two rats died.
(18) Cleaning naphtha, a product of Chinese Petroleum Corporation, is a complex hydrocarbon mixture which contains mainly aliphatic hydrocarbons.
(19) The central nervous system depression described in acute exposure cases of the intact (not distillate) petroleum naphtha fumes was not observed in any of this series.
(20) The study population included 59 women who had been exposed to petroleum naphtha and toluene and 24 age-matched control women.