angular displacement resolution
31Introduction to quantum mechanics — This article is an accessible, non technical introduction to the subject. For the main encyclopedia article, see Quantum mechanics. Quantum mechanics …
32Transmission electron microscopy — A TEM image of the polio virus. The polio virus is 30 nm in size.[1] Transmission electron microscopy (TEM) is a microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it… …
33Quartz crystal microbalance — A quartz crystal microbalance (QCM) measures a mass per unit area by measuring the change in frequency of a quartz crystal resonator. The resonance is disturbed by the addition or removal of a small mass due to oxide growth/decay or film… …
34United States — a republic in the N Western Hemisphere comprising 48 conterminous states, the District of Columbia, and Alaska in North America, and Hawaii in the N Pacific. 267,954,767; conterminous United States, 3,022,387 sq. mi. (7,827,982 sq. km); with… …
35geology — /jee ol euh jee/, n., pl. geologies. 1. the science that deals with the dynamics and physical history of the earth, the rocks of which it is composed, and the physical, chemical, and biological changes that the earth has undergone or is… …
36Atom — The atom is the smallest unit of an element that retains the chemical properties of that element. An atom has an electron cloud consisting of negatively charged electrons surrounding a dense nucleus. The nucleus contains positively charged… …
37atmosphere — atmosphereless, adj. /at meuhs fear /, n., v., atmosphered, atmosphering. n. 1. the gaseous envelope surrounding the earth; the air. 2. this medium at a given place. 3. Astron. the gaseous envelope surrounding a heavenly body. 4. Chem. any… …
38Comparison of analog and digital recording — This article compares the two ways in which sound is recorded and stored. Actual sound waves consist of continuous variations in air pressure. Representations of these signals can be recorded using either digital or analog techniques. An analog… …
39Asteroid — For the arcade video game, see Asteroids (video game). For other uses, see Asteroid (disambiguation). A composite image, to scale, of the asteroids that have been imaged at high resolution. As of 2011 they are, from largest to smallest: 4 Vesta,… …
40Thermodynamic temperature — is the absolute measure of temperature and is one of the principal parameters of thermodynamics. Thermodynamic temperature is an “absolute” scale because it is the measure of the fundamental property underlying temperature: its null or zero point …
