(1) Convincing evidence suggests that both the Ir spike and the extinction event were caused by the collision of a large bolide (greater than 10 km in diameter) with the Earth.
Boride
Definition:
(n.) A binary compound of boron with a more positive or basic element or radical; -- formerly called boruret.
Example Sentences:
(1) The risetime of the photogating effect increases with increasing concentration of tetraphenyl boride.
(2) In the region of saturated conductance of boride ion, the increase in conductivity is 3.6-fold.
(3) Special ceramic hard substances, such as silicides and borides, are used as separating agents for the casting of the secondary structure.
(4) There are several materials whose thermionic emission properties are better than those of tungsten or compatible to those of tungsten among the carbides and borides, such as TaC, HfC, ZrC, LaB6, and CeB6, as judged by the figure of merit.
(5) Thermionic emission properties of several kinds of refractory carbides, nitrides, and borides of the transition metals in the form of powder were investigated with a newly developed measuring device and evaluated by the figure of merit defined as the ratio of the effective work function to the working temperature at which the vapor pressure becomes 1 x 10(-5) Torr.
(6) From the brightness characteristics, it was found that some of carbides, carbide solid solutions, and borides such as HfC, ZrC (Ta0.8-0.7Hf0.2-0.3)C, TaB2, and HfB2 are very good emitters comparable to LaB6.
(7) These calculations indicate that there is insufficient porphyrin charge density to cancel the boride ion space charge and the following article proposes a novel ion chain mechanism to explain these effects.
(8) New preparation methods for carburization, nitriding, and boriding of the wires of matrix metals and alloys were successfully developed for using these materials as the cathode of the electron microscope.