(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.
Hydrocarbon
Definition:
(n.) A compound containing only hydrogen and carbon, as methane, benzene, etc.; also, by extension, any of their derivatives.
Example Sentences:
(1) The high transition enthalpy for kerasin is ascribed to a lesser accommodation of gauche conformers in the hydrocarbon chains just below the transition temperature.
(2) Aryl hydrocarbon hydroxylase (AHH) inducibility, carbon monoxide in expired air (CO), serum gammaglutamyl-transferase (GGT), and total cholesterol were compared in equal-sized, age-matched samples of healthy middle-aged males born in 1921, 1934-1936, and 1946 attending the ongoing preventive medical population program in Malmö.
(3) The length of the hydrocarbon chains of the surface-modified silica supports had no significant influence on the selectivity.
(4) The specificity of binding to microsomal proteins of metabolically activated hydrocarbons has been studied.
(5) Aryl hydrocarbon (benzo(a)pyrene) hydroxylase is present and inducible in Buffalo rat liver cells in culture.
(6) The possible occupational cause of the disease, as more solvents in the mud have the structure of aromatic hydrocarbons is discussed.
(7) Experiments with a series of adsorbents homologous with CPAD-Sepharose, in which the length of the hydrocarbon chain was varied, provided strong evidence of hydrophobic interactions, in addition to ionic interactions, in the binding of these proteins to CPAD-Sepharose.
(8) In the hydrocarbon promotion study, dose related increases were observed in the incidence of ACF in male rats promoted with UG or 50 ppm TMP for 24 or 60 weeks.
(9) The results also demonstrated that there was not any apparent correlation between the receptor-binding avidities and in vitro monooxygenase enzyme-induction potencies for the most active polynuclear aromatic hydrocarbons.
(10) Both main-stream and side-stream cigarette smoke condensates and some fractions, containing water-soluble bases, water-insoluble bases, and polycyclic aromatic hydrocarbons, were found to induce AHH activity in lung and liver, the lung being induced to the greatest extent.
(11) Pancreas transplantation offers the possibility of preventing the development and progression of diabetic lesions by adequate control of hydrocarbon metabolism.
(12) A comparison of the relative cytosolic Ah (9S) receptor binding affinities and aryl hydrocarbon hydroxylase (AHH) induction potencies of these hydrocarbons with their 4S protein binding affinities demonstrated the following: five compounds, namely 1,2,5,6-dibenz[a]-anthracene, 1,2,3,4-dibenz[a]anthracene, picene, benzo[a]pyrene and 3-methylcholanthrene exhibited high to moderate binding affinities for the 4S and 9S cytosolic proteins (EC50 values less than 10(-6) M) and induced AHH in rat hepatoma cells; three compounds, namely perylene, benzo[e]pyrene and benzo[g,h,i]perylene exhibited high affinities for the 4S binding protein (1.25 X 10(-7), 4.4 X 10(-8) and 2.9 X 10(-8) M, respectively) and low affinities (EC50 values greater than 10(-5) M) for the Ah receptor protein; moreover these three compounds did not induce AHH in rat hepatoma H-4-II E cells in culture.
(13) It was found that HBSAg was strongly bound to straight hydrocarbon chains with more than seven carbon atoms.
(14) The parent hydrocarbons and the related K-region dihydrodiols induced some sister-chromatid exchanges but they were considerably less active than these two non-K-region diols.
(15) The effect of various fuel additives on the ability of platinum-palladium catalytic converters to remove the carbon monoxide and hydrocarbon components of automotive exhaust has been examined.
(16) Other chlorinated hydrocarbons as decachlorobiphenyl, pentachloronaphthalene, hexachloronaphthalene and hexachlorostyrene were identified, but not quantified.
(17) It has been estimated that natural oil seeps may also contribute as much as 10% of the hydrocarbons in the global marine environment.
(18) The metabolic fate of the carcinogenic aza-aromatic hydrocarbon 7-methyl[7-(14)C]benz[c]acridine (14C-7MBAC) was studied in hepatocytes freshly isolated from untreated, phenobarbital-pretreated and 3-methylcholanthrene-pretreated rats.
(19) Renal cytochrome P450, aryl hydrocarbon hydroxylase, 7-ethoxycoumarin-O-deethylase, and benzphetamine N-demethylase were increased after partial hepatectomy by 84%, 360%, 165% and 406%, respectively.
(20) Antioxidants devoid of hydrocarbon tails, are 10-20 fold more potent LPO inhibitors than the corresponding AOs with hydrocarbon tails.