Search results
Results from the WOW.Com Content Network
[15] k 1 is the rate constant for chemical uptake from water at the respiratory surface (L*kg −1 *d −1). [15] C WD is the chemical concentration dissolved in water (g*L −1 ). [ 15 ] k 2 ,k E ,k G ,k B are rate constants that represent excretion from the organism from the respiratory surface, fecal excretion, metabolic transformation, and ...
Bromochlorodifluoromethane (BCF), also referred to by the code numbers Halon 1211 and Freon 12B1, is a haloalkane with the chemical formula C F 2 Cl Br. It is used for fire suppression, especially for expensive equipment or items that could be damaged by the residue from other types of extinguishers. [ 1 ]
Tris (pentafluorophenyl)borane, sometimes referred to as "BCF", is the chemical compound (C6F5)3B. It is a white, volatile solid. The molecule consists of three pentafluorophenyl groups attached in a "paddle-wheel" manner to a central boron atom; the BC3 core is planar. It has been described as the “ideal Lewis acid ” because of its high ...
Warmer, ice-free conditions in the southeast Bering Sea are roughly 200 times more likely now than before humans began burning planet-warming fossil fuels.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
It has a mean lifetime of 0.12 ns and decays preferentially into two gamma rays with energy of 511 keV each (in the center-of-mass frame). Para-positronium can decay into any even number of photons (2, 4, 6, ...), but the probability quickly decreases with the number: the branching ratio for decay into 4 photons is 1.439(2) × 10 −6. [1]
ν = 1 420 405 751.768(2) Hz. in a vacuum. [3] This transition is highly forbidden with an extremely small transition rate of 2.9 × 10 −15 s −1, [4] and a mean lifetime of the excited state of around 11 million years. [3] Collisions of neutral hydrogen atoms with electrons or other atoms can help promote the emission of 21 cm photons. [5]
The report said that about 0.6% of the U.S. population — about 1.9 million people — are on water systems with naturally occurring fluoride levels of 1.5 milligrams or higher.