Search results
Results from the WOW.Com Content Network
Terrarium. A terrarium ( pl.: terraria or terrariums) is usually a sealable glass container containing soil and plants that can be opened for maintenance to access the plants inside; however, terraria can also be open to the atmosphere. Terraria are often kept as ornamental items. A closed terrarium's transparent walls allow heat and light to ...
Thoriated glass is a glass material used in the manufacture of optical systems, specifically photographic lenses. It is useful to this process due to its high refractive index. Thoriated glass is radioactive due to the inclusion of thorium dioxide, oxide of radioactive element thorium. It has therefore been succeeded as a material of choice by ...
Thorium dioxide (ThO 2 ), also called thorium (IV) oxide, is a crystalline solid, often white or yellow in colour. Also known as thoria, it is mainly a by-product of lanthanide and uranium production. [ 4] Thorianite is the name of the mineralogical form of thorium dioxide. It is moderately rare and crystallizes in an isometric system.
Thorium ( 90 Th) has seven naturally occurring isotopes but none are stable. One isotope, 232 Th, is relatively stable, with a half-life of 1.405×10 10 years, considerably longer than the age of the Earth, and even slightly longer than the generally accepted age of the universe. This isotope makes up nearly all natural thorium, so thorium was ...
Point of view (literature) or narrative mode, the perspective of the narrative voice; the pronoun used in narration; Point of view (painting), the angle of painter vision; Point of view (pornography), a subset of gonzo pornography in which the performer also holds the camera; Point-of-view shot, a technique in motion photography
A point of view shot (also known as POV shot, first-person shot or subjective camera) is a film scene —usually a short one—that is shot as if through the eyes of a character (the subject). The camera shows what the subject's eyes would see. It is usually established by being positioned between a shot of a character looking at something, and ...
Thorium reacts with hydrogen to form the thorium hydrides ThH 2 and Th 4 H 15, the latter of which is superconducting below the transition temperature of 7.5–8 K; at standard temperature and pressure, it conducts electricity like a metal. [12] Thorium is the only metallic element that readily forms a hydride higher than MH 3. [31]
Monazite contains 2.5% thorium, allanite has 0.1 to 2% thorium and zircon can have up to 0.4% thorium. [2] Thorium-containing minerals occur on all continents. [3] [4] [5] Thorium is several times more abundant in Earth's crust than all isotopes of uranium combined and thorium-232 is several hundred times more abundant than uranium-235. [6]