Science — page 120 of 132

13,110 terms including subtopics (0 terms filed directly here)

Science terms

Thermocline A distinct layer of water where rising warm and sinking cold water meet but do not mix.
Thermocouple A device consisting of two dissimilar conductors with their ends connected together.
Thermodynamic Chart A chart containing contours of pressure, temperature, moisture, and potential temperature, all drawn relative to each other such that basic thermodynamic…
Thermodynamic Cycle An idealized process in which a working fluid (water, air, ammonia, etc) successively changes its state (from a liquid to a gas and back to a liquid) for…
Thermodynamic Diagram Used interchangably with Thermodynamic Chart; a chart containing contours of pressure, temperature, moisture, and potential temperature, all drawn…
Thermodynamics A study of the transformation of energy from one form to another, and its practical application. (see Law(s) of Thermodynamics above).
Thermoelectric (power) water use Water used in generating electricity with steam-driven turbine generators. Power plants that burn coal and oil are examples of thermoelectric-power…
Thermoelectric Conversion The conversion of heat into electricity by the use of thermocouples.
Thermograph An instrument that measures and records air temperature.
Thermography (ther-MAH-gruh-fee) In medicine, a procedure in which a heat-sensing infrared camera is used to record the surface heat produced by different parts of the…
Thermohaline Circulation Large-scale density-driven circulation in the ocean, caused by differences in temperature and salinity.
thermohaline circulation (THC) density-driven circulation system in the world's oceans. In the Atlantic, warm water flows northward in the surface ocean, loses heat to the overlying…
thermolabile Not resistant to heat, often in the context of a molecule which is unstable upon heating. Opposite: thermostable.
Thermometer An instrument for measuring air temperature.
thermophile An organism which is adapted to high temperatures, such as in hot springs and geysers, smoker vents on the sea floor, and domestic hot water pipes.
Thermophotovoltaic Cell A device where sunlight concentrated onto a absorber heats it to a high temperature, and the thermal radiation emitted by the absorber is used as the…
Thermopile A large number of thermocouples connected in series.
thermosensitivity Loss of biological activity of a molecule at high temperature.
Thermosiphon The natural, convective movement of air or water due to differences in temperature.
Thermosiphon System This passive solar hot water system consists relies on warm water rising, a phenomenon known as natural convection, to circulate water through the…
Thermosphere The atmospheric shell extending from the top of the mesosphere to outer space. It is a region of more or less steadily increasing temperature with height…
thermostable A molecule which retains its biological activity at some specified higher temperature. Opposite: thermolabile.
Thermostat A device used to control temperatures; used to control the operation of heating and cooling devices by turning the device on or off when a specified…
thermotherapy (THER-moh-THAYR-uh-pee) Treatment of disease using heat.
Theta-e (or Equivalent Potential Temperature) - The temperature a parcel of air would have if a) it was lifted until it became saturated, b) all water vapor was…
Theta-e Ridge An axis of relatively high values of theta-e. Severe weather and excessive rainfall often occur near or just upstream from a theta-e ridge.
THETAE Abbreviation for Theta-e; the temperature a parcel of air would have if a) it was lifted until it became saturated, b) all water vapor was condensed out…
Thiazolidinediones A class of antidiabetes drugs that enhances the activity of insulin.
Thick arch dam An arch dam with a base thickness to structural height ratio of 0.3 or greater (previously defined as 0.5 or greater).
Thickness or width of dam The thickness or width of a dam as measured horizontally between the upstream and downstream faces and normal to the axis or centerline crest of the dam.
Thin arch dam An arch dam with a base thickness to structural height ratio of 0.2 or less (previously defined as 0.3 or less).
Thin film A layer of semiconductor material, such as copper indium diselenide or gallium arsenide, a few microns or less in thickness, used to make solar…
Thin Line Echo A narrow, elongated, non-precipitating echo. It is usually associated with thunderstorm outflows, fronts, or other density discontinuities.
thinning 1. Removal of older stems to promote new growth. 2. Removal of excess fruits to improve the size and quality of the remaining fruits. 3.
Thixotrophy The property of a material that enables it to stiffen in a relatively short time on standing but, upon agitation or manipulation, to change to a very soft…
THK Thick/Thickness
THN Thin
Thorn forest A type of forest formation, mostly tropical and subtropical, intermediate between desert and steppe, dominated by small trees and shrubs.
Threatened A legal classification for a species which is likely to become endangered within the foreseeable future.
Threatened species Any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.
Threatened, endangered and sensitive species (TE&S) (TE&S) Formal classifications of species. Sensitive: Species for which population viability is a concern.
Three-Hour Rainfall Rate This WSR-88D Radar product displays precipitation total (in inches) of the current and past two clock hours as a graphical image.
Three-phase Current Alternating current in which three separate pulses are present, identical in frequency and voltage, but separated 120 degrees in phase.
Threshold the point a system must cross to enter a new state or condition.
Threshold Runoff The runoff in inches from a rain of specified duration that causes a small stream to slightly exceed bankfull.
THRFTR Thereafter
Thrombocyte (Platelet) A tiny, disc-shaped blood cell responsible for controlling abnormal or excessive bleeding.
Thrombopoietin (THROM-boh-POY-eh-tin) A substance made by the body that helps make blood cells, especially platelets.
Through cut An excavation between parallel banks that begins and ends at original grade.
THRU Through
Thrust block (anchor block) A massive block of concrete built to withstand a thrust or pull. A mass of concrete or similar material appropriately placed around a pipe to prevent…
THRUT Throughout
THSD Thousand
Thunder The sound caused by rapidly expanding gases in a lightning discharge.
Thunderstorm A local storm produced by a cumulonimbus cloud and accompanied by lightning and thunder.
thymidine A chemical compound found in DNA. Also used as treatment for mucositis.
thymidine kinase (Abbreviation: tk). An enzyme that allows a cell to utilize an alternate metabolic pathway for incorporating thymidine into DNA.
Thymidine kinase (tk) An enzyme that allows a cell to utilize an alternate metabolic pathway for incorporating thymidine into DNA.
thymidine triphosphate Abbreviation: TTP; dTTP is strictly correct but rarely used.
thymidylic acid (Abbreviation: TMP or dTMP). Synonym for thymidine 5'-monophosphate, a deoxyribonucleotide containing the nucleoside thymidine.
thymine (Abbreviation: T). One the bases found in DNA. See: thymidine.
Thymine (T) A nitrogenous base, one member of the base pair AT (adenine-thymine). See also: base pair, nucleotide
Thymus An organ that is part of the lymphatic system, in which T lymphocytes grow and multiply. The thymus is in the chest behind the breastbone.
Ti (tumor-inducing) plasmid A giant plasmid of Agrobac- terium tumefaciens that is responsible for tumor formation in infected plants.
Ti plasmid Tumour-inducing plasmid. A large plasmid present in pathogenic Agrobacterium tumefaciens, responsible for the induction of tumours in plant with crown…
Tidal Cycle The periodic changes in the intensity of tides caused primarily by the varying relations between the earth, moon, and sun.
Tidal Piling Occurs when unusually high water levels occur as the result of an accumulation of successive incoming tides that do not completely drain due to opposing…
Tidal Power The power available from the rise and fall of ocean tides. A tidal power plant works on the principal of a dam or barrage that captures water in a basin…
Tidal Wave See TSUNAMI
TIDE The periodic, rhythmic rise and fall of the sea surface that results from the gravity of the moon and sun acting on the rotating Earth.
Tide Anomaly Actual water level minus the prediction.
Tide Prediction The computation of tidal highs and lows at a given location resulting from the gravitational interactions between the earth and primarily the moon and sun.
Tidelands The zone between the mean high water and mean low water lines.
Tides The periodic (occurring at regular intervals) variations in the surface water level of the oceans, bays, gulfs, and inlets.
Tie lines Transmission line connecting two or more power systems.
Tier 1 Reclamation public protection guideline dealing with loss of life (LOL) considerations. See annualized loss of life.
Tier 2 Reclamation public protection guideline dealing with public trust responsibilities based on the annual failure probability of the structure.
Tiering The coverage of general matters in a broad National Environmental Policy Act document with subsequent narrowly focused documents; helps to eliminate…
Tight This is an undesirable condition of the race car. A NASCAR race car is tight when the front wheels loose grip before the rear wheels loose grip when going…
TIL Until
Tile Pipe made of baked clay.
Till A deposit of sediment formed under a glacier, consisting of an unlayered mixture of clay, silt, sand, and gravel ranging widely in size and shape.
Tillage Plowing, seedbed preparation, and cultivation practices. See conventional tillage.
Tilt To play wildly or recklessly. A player is said to be "on tilt" if he is not playing his best, playing too many hands, trying wild bluffs, raising with bad…
Tilt Angle (of a Solar Collector or Module) The angle at which a solar collector or module is set to face the sun relative to a horizontal position.
Tilt Sequence Radar term indicating that the radar antenna is scanning through a series of antenna elevations in order to obtain a volume scan.
Tilted Storm A thunderstorm or cloud tower which is not purely vertical but instead exhibits a slanted or tilted character.
Tilted Updraft A thunderstorm updraft which is not purely vertical but instead exhibits a slanted or tilted character.
Tilth Soil condition in relation to lump or particle size.
Timber Wood beams larger than 4 x 6.
Timber stand improvement Intermediate pruning, weeding, and thinning of a stand of timber prior to its reaching mature rotation age to improve growing conditions and control stand…
Timbering Wood bracing in a tunnel or excavation.
Timbering set A tunnel support consisting of a roof beam or arch, and two posts.
Timberland Forest land capable of producing 20 cubic feet of wood per acre per year.
Time of concentration The time required for storm runoff to flow from the most remote point of a catchment or drainage area to the outlet or point under consideration.
Time-of-Use (TOU) Rates The pricing of electricity based on the estimated cost of electricity during a particular time block.
Time-of-use pricing A rate design imposing higher charges to customers during periods of the day when higher demand is experienced.
Timer A device that can be set to automatically turn appliances (lights) off and on at set times.
Timer (Water Heater) This device can automatically turn the heater off at night and on in the morning.
Tip Speed Ratio In reference to a wind energy conversion device's blades, the difference between the rotational speed of the tip of the blade and the actual velocity of…