(n.) A gaseous compound of carbon and hydrogen, in the proportion of two atoms of the former to two of the latter. It is a colorless gas, with a peculiar, unpleasant odor, and is produced for use as an illuminating gas in a number of ways, but chiefly by the action of water on calcium carbide. Its light is very brilliant.
Example Sentences:
(1) Optimum rates of acetylene reduction in short-term assays occurred at 20% O2 (0.2 atm (1 atm = 101.325 kPa] in the gas phase.
(2) On siratro, CIAT899 induced nodules that were ineffective in acetylene reduction, whereas the EPS-deficient mutants induced effective nodules.
(3) It is suggested that acetylene reduction assays may not be accurately applied to samples containing methane oxidizing bacteria.
(4) Biological nitrogen fixation, as determined by acetylene reduction, occurs in Lake Erie.
(5) Some of the thiophenes and their acetylenic derivatives possess extremely potent phototoxic activities toward membrane-containing viruses.
(6) The efficiencies of the different positional isomers in supporting cell proliferation varied from essentially 0 cells per fmol for the 2-5 and 13-17 isomers to high values when the acetylenic bond was near the center of the chain: e.g.
(7) If the cultures were grown in media with NH4+, NO3-, urea, glutamine or asparagine, hydrogen photoevolution by the cells and acetylene reduction started after the lag-phase and proceeded at a low rate.
(8) Under suitable growth conditions the acetylenic acids are catabolized and partly reused via acetate for de novo synthesis of fatty acids.
(9) 2-Ethynyl-4,5-diphenylthiazoles were synthesized by the palladium catalyst cross-coupling reaction of 2-iodo-4,5-diphenylthiazole with monosubstituted acetylenes.
(10) The conditions which are necessary for the synthesis and function of this system were studied in whole cells by using acetylene reduction as a sensitive assay for the presence of the N(2)-fixing system.
(11) However, in culture under aerobic conditions, large, phase-bright vesicles are formed in HFPCcI3 within 20 h following removal of NH+4 from the culture medium and reach peak numbers within 72 to 96 h. In vivo acetylene reduction activity parallels vesicle formation.
(12) Vesicles permeabilized by freeze-thaw or detergents showed increased rates of acetylene reduction due to increased permeability of dithionite.
(13) After 30 minutes at this new driving force, four timed acetylene samples were again collected.
(14) 3-(1,2,3-Triazol-1-yl)methylcephalosporins have been prepared by the direct cycloaddition of acetylene to 3-azidomethylcephalosporins, which were obtained by nucleophilic substitution of 3-chloromethylcephalosporins with sodium azide in N,N-dimethylformamide.
(15) Biological dinitrogen fixation in mangrove communities of the Tampa Bay region of South Florida was investigated using the acetylene reduction technique.
(16) Nitrate reductase (nar) A, B and E mutants of Escherichia coli with plasmids carrying Klebsiella pneumoniae nitrogen fixation (nif) genes reduced acetylene independently of added molybdate, but nar D mutants showed pleiotropic dependence on the concentration of added molybdate for expression of both nar and nif.
(17) Two important side reactions of this procedure are known: the formation of the isomeric beta-ethynyl derivative and the formation of a dimeric product with acetylene bridge.
(18) Acetylene-reducing activity of purified nitrogenase from Klebsiella pneumoniae was studied over a range of ATP and Mg(2+) concentrations at 15 degrees C, pH7.8.
(19) The reconstituted acid mixture is injected into the graphite tube atomizer for analysis of Cu and Cd and aspirated into the air--acetylene flame for measurement of Zn.
(20) The 19-acetylenic testosterone, a confirmed metabolite from primate studies, was 25% as efficient as MDL 18,962 for aromatase inactivation, while 6 beta-hydroxy- and 6-oxo analogs were 11% and 5%, respectively as efficient as their parent compound.
Illuminating
Definition:
(p. pr. & vb. n.) of Illuminate
(a.) Giving or producing light; used for illumination.
Example Sentences:
(1) It is concluded that in the mouse model the ability of buspirone to reduce the aversive response to a brightly illuminated area may reflect an anxiolytic action, that the dorsal raphe nucleus may be an important locus of action, and that the effects of buspirone may reflect an interaction at 5-hydroxytryptamine receptors.
(2) With this system, a brain region loaded with fura-2 was illuminated by a rotating disc bearing three different interference filters of 340, 360 and 380 nm at a rate of 600 rpm.
(3) Naloxone injection into those rats exposed to constant illumination significantly increased hypothalamic levels of beta-endorphin compared to saline injected controls.
(4) These data show an extra-hepatic lipolytic effect of glucagon in vivo, but do not illuminate the significance of this effect in the intact animal.
(5) The illumination of the F1-ATPase complexes with NAB-ADP or NAB-GDP leads to the covalent binding of one nucleotide analogue molecule to the enzyme and to the irreversible inactivation of F1-ATPase.
(6) Both eosin derivatives, however, inactivate acetylcholinesterase upon illumination of air-equilibrated samples of hemoglobin-free labeled ghosts.
(7) This 520-nm change can be used for the continuous measurement of pH changes in thylakoids during steady-state illumination.
(8) Photosynthetic activity of the cells was checked by placing the cell evenly illuminated in a (14)CO(2) atmosphere.
(9) The visual processes revealed in these experiments are considered in terms of inferred illumination and surface reflectances of objects in natural scenes.
(10) The second triplet, which was stable in the dark at 4.2 K following illumination, was assigned to the radical pair Donor+I-.
(11) Superoxide anion (O2.-) was photogenerated upon illumination of riboflavin in fluorescent light.
(12) One of these has high sporulation-inducing activity after illumination in vitro.
(13) Upon illumination, a dark-adapted photosynthetic sample shows time-dependent changes in chlorophyll (Chl) a fluorescence yield, known as the Kautsky phenomenon or the OIDPS transient.
(14) The effects of continuous illumination, adrenalectomy and induction or inhibition of microsomal enzymes on antipyretic action of phenacetin were evaluated.
(15) Out of the seabird whoops and thrashing drumming of the intro to Endangered Species come guitar-sax exchanges that sound like Prime Time’s seething fusion soundscapes made illuminatingly clearer.
(16) As the differential diagnosis between Crohn's disease and appendicitis is difficult and the surgical approach to the appendix in the presence of Crohn's disease is controversial, we illuminate some practical points in the preoperative evaluation of these patients and deal with the question of whether appendectomy should be performed in these patients.
(17) superficial or interstitial illumination) and the optical interaction coefficients of the irradiated tissue.
(18) Activity was stimulated by the change in illumination levels at dawn and dusk.
(19) On prolonged UV-A illumination the ESR spectrum of 16-doxylstearic acid in dimyristoyl phosphatidylcholine vesicles loaded with 8-methoxypsoralen changed dramatically as a second broad component gradually appeared.
(20) All plasma porphyrins could be protected for several days from similar photodegradation by performing all blood drawing, processing, and assay procedures under ordinary red-incandescent illumination, and by storage in the dark.