Sodium silicate — E550 redirects here. For the Italian locomotive, see FS Class E550 Sodium silicate … Wikipedia
Positive feedback — Alarm or panic can spread by positive feedback among a herd of animals to cause a stampede. Positive feedback is energy taken from the output of a system and reapplied to the input, which is phase congruent with the input signal. A system… … Wikipedia
Membrane potential — Differences in concentration of ions on opposite sides of a cellular membrane lead to a voltage called the membrane potential. Many ions have a concentration gradient across the membrane, including potassium (K+), which is at a high inside and a… … Wikipedia
nuclear reactor — Physics. reactor (def. 4). Also called nuclear pile. [1940 45] * * * Device that can initiate and control a self sustaining series of nuclear fission reactions. Neutrons released in one fission reaction may strike other heavy nuclei, causing them … Universalium
Battery (electricity) — For other uses, see Battery (disambiguation). Various cells and batteries (top left to bottom right): two AA, one D, one handheld ham radio battery, two 9 volt (PP3), two AAA, one C, one … Wikipedia
Glass ionomer cement — A Glass Ionomer Cement (GIC) is one of a class of materials commonly used in dentistry as filling materials and luting cements. These materials are based on the reaction of silicate glass powder and polyalkeonic acid. These tooth coloured… … Wikipedia
Nuclear fuel — Process … Wikipedia
Action potential — In physiology, an action potential is a short lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called… … Wikipedia
renal system — ▪ anatomy Introduction in humans (human body), organ system that includes the kidneys, where urine is produced, and the ureters, bladder, and urethra for the passage, storage, and voiding of urine. In many respects the human excretory, or… … Universalium
building construction — Techniques and industry involved in the assembly and erection of structures. Early humans built primarily for shelter, using simple methods. Building materials came from the land, and fabrication was dictated by the limits of the materials and… … Universalium
drug — drug1 /drug/, n., v., drugged, drugging. n. 1. Pharm. a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well being. 2. (in federal law) a. any substance… … Universalium