Science terms starting with D

722 terms

  1. Department of Energy (DOE) In 1989, the Department of Energy (DOE) created the Office of Environmental Management (EM) to mitigate the risks and hazards posed by the legacy of…
  2. Dependable Capacity The load-carrying ability of an electric power plant during a specific time interval and period when related to the characteristics of the load to…
  3. Depletion Net loss of water through consumption, export, and other uses to a given area, river system, or basin.
  4. Depletion Curve That part of the hydrograph extending from the point of termination of the Recession Curve to the subsequent rise or alternation of inflow due to…
  5. Deposit An amount of money paid to the court. Hennepin County Housing Court can only accept cash and certified checks; personal checks, third-party checks, and…
  6. Deposition An oral statement made before an officer authorized by law to administer oaths.
  7. Depression A depression is a severe and prolonged downturn in the economy. Prices fall, reducing purchasing power.
  8. Depression Storage The volume of water contained in natural depressions in the land surface, such as puddles.
  9. Depth of cutoff The vertical distance that the cutoff penetrates into the dam foundation.
  10. Depth of Runoff The total runoff from a drainage basin, divided by its area. For convenience in comparing runoff with precipitation, the term is usually expressed in…
  11. Depth of snow Depth of snow Vertical interval between the top surface of a snow layer and the ground beneath; the layer is assumed to be evenly spread over the ground…
  12. Derating The production of energy by a system or appliance at a level less than its design or nominal capacity.
  13. Derecho (Pronounced day-RAY-cho), a widespread and usually fast-moving windstorm associated with convection.
  14. Deregulation The process of changing regulatory policies and laws to increase competition among suppliers of commodities and services.
  15. derepression The process of "turning on" the expression of a gene or set of genes whose expression has been repressed (turned off), usually by the displacement of a…
  16. Derivative Derivatives are financial products, such as futures contracts, options, and mortgage-backed securities.
  17. derived product A new datastream generated by applying an algorithm or model to existing data.
  18. Derived Products Processed base data on the Doppler radar.
  19. dermal uptake The transfer of a contaminant from air, water, or soil into or through the outer skin layer; considered an exposure route in an exposure assessment.
  20. Derrick Usually a non-mobile tower equipped with a hoist, but may be used as a synonym for a crane.
  21. Desalinization The removal of dissolved salts from water by natural means (leaching) or by specific water treatment processes.
  22. Desert Arid region receiving less than 10 inches of precipitation annually.
  23. Desert bench A relatively flat terrace elevated above the surface of a desert alluvial feature, such as an ephemeral stream or wash.
  24. Desert dune A wind-created ridge or mound of sand that is found in deserts or near oceans and lakes.
  25. Desert floor The land surface in a desert valley.
  26. Desert focal bird species Bird species whose requirements define spatial attributes, habitat characteristics, and management regimes representative of a healthy desert system.
  27. Desert pavement A surface layer of closely packed, loosely cemented pebbles. See also Pediment
  28. Desert riparian habitat Habitats characterized as dense groves of low shrublike trees, or tall shrubs to woodlands of small to medium-sized trees.
  29. Desert scrub The desert scrub community is characterized by plants adapted to seasonally dry climate.
  30. Desert varnish The thin red to black coating found on exposed rock surfaces in arid regions. Varnish is composed of clay minerals, oxides, and hydroxides of manganese…
  31. Desert wash A usually dry desert streambed that flows only after periods of heavy rain.
  32. Desertification When soil erosion is so severe that plants and animals can no longer exist.
  33. Desiccant Any compound used to remove moisture or water.
  34. Desiccant Cooling To condition/cool air by dessication.
  35. Desiccate To dry up; remove moisture from a substance.
  36. Desiccation The process of removing moisture; involves evaporation.
  37. Design basis The set of conditions, dimensions, needs, and requirements used to design a solar energy facility.
  38. Design basis earthquake (DBE) The earthquake which the structure is required to safely withstand with repairable damage.
  39. Design Cooling Load The amount of conditioned air to be supplied by a cooling system; usually the maximum amount to be delivered based on a specified number of cooling degree…
  40. Design Criteria The hypothetical flood used in the sizing of the dam and the associated structures to prevent dam failure by overtopping, especially for the spillway…
  41. Design features Measures or procedures incorporated into the proposed action or alternatives which could avoid or reduce adverse impacts.
  42. Design Flood The largest flood that a given project is designed to safely accommodate. The reservoir inflow hydrograph used to estimate the spillway discharge capacity…
  43. Design Heating Load The amount of heated air, or heating capacity, to be supplied by a heating system; usually the maximum amount to be delivered based on a specified number…
  44. Design Life Period of time a system or appliance (or component of) is expected to function at its nominal or design capacity without major repair.
  45. Design response spectra Smooth, broad-banded spectra appropriate for specifying the level of seismic design force, or displacement, for earthquake-resistant design purposes.
  46. Design Standards Design standards or guidelines can serve as a community's desire to control its appearance, from within and without, through a series of standards that…
  47. Design summary A document that summarizes the designers' development of the design that results in the specifications.
  48. Design Temperature The temperature that a system is designed to maintain (inside) or operate against (outside) under the most extreme conditions.
  49. Design Tip Speed Ratio For a wind turbine, the ratio of the speed of the tip of a turbine blade for which the power coefficient is at maximum.
  50. Design Voltage The nominal voltage for which a conductor or electrical appliance is designed; the reference voltage for identification and not necessarily the precise…
  51. Design water level The maximum water elevation, including the flood surcharge, that a dam is designed to be able to withstand.
  52. Design wind The most severe wind that is reasonbly possible at a particular reservoir for generating wind setup and runup.
  53. Designated floodway The channel of a water course and those portions of the adjoining flood plain required to provide for the passage of a selected flood with a small…
  54. Designated frequency flood Refers to the probability that a flood will occur in a given year. A 100-year flood is often considered in the design of diversion dams and for…
  55. Designated Roads and Trails Specific roads and trails identified by the agencies where some type of motorized vehicle use is appropriate and allowed, either seasonally or yearlong.
  56. Designers' Operating Criteria (DOC) Detailed operating criteria which stress the designer's intended use and operation of equipment and structures in the interest of safe, proper, and…
  57. Desired future condition A vision of the desired future state of a specific area. A description of land and resource conditions expected to result if management goals and…
  58. Desorption The release or removal of an adsorbed material from the surface of a solid adsorbent.
  59. desoxyribonucleic acid Obsolete spelling of deoxyribonucleic acid.
  60. Destratification The development of vertical mixing within a lake or reservoir to eliminate (either totally or partially) separate layers of temperature, plant, or animal…
  61. desulphurization See: biodesulphurization.
  62. Desuperheater An energy saving device in a heat pump that, during the cooling cycle, recycles some of the waste heat from the house to heat domestic water.
  63. Detection The first of five Early Warning System components consisting of the processes and equipment necessary to collect information about the threatening event…
  64. Detention Basins Detention basins are normally dry, but are designed to detain surface water temporarily during, and immediately after a runoff event.
  65. Detention dam A dam built to store streamflow or surface runoff, and to control the release of such stored water.
  66. Detention Ponds (Extended Detention Basins) An area surrounded by an embarkment, or an excavated pit, designed to temporarily hold stormwater long enough to allow…
  67. Detention Storage The volume of water, other than depression storage, existing on the land surface as flowing water which has not yet reached the channel.
  68. detergent Substance which lowers the surface tension of a solution, improving its cleaning properties.
  69. determinate growth Growth determined and limited in time, with a bud or flower terminating the growth of the main axis. Once established, it is usually irreversible.
  70. determination Process by which undifferentiated cells in an embryo become committed to develop into specific cell types, such as neurons, fibroblasts or muscle cells.
  71. determined Describing embryonic tissue at a stage when it can develop only as a certain kind of tissue.
  72. Detonating cord Round, flexible textile, or plastic cord with a center core of high explosive. A common use is to tie in shots using nonelectric delays (MS connectors)…
  73. Detonation Practically instantaneous decomposition or combustion of an unstable compound, with tremendous increase in volume.
  74. Detonator A device to start an explosion, as a fuse or cap.
  75. Detritus Loose natural materials, such as rock fragments or organic particles, that result directly from disintegration of rocks or organisms.
  76. Deuterium A special form of hydrogen (an isotope called "heavy hydrogen") that has a neutron as well as a proton in its nucleus.
  77. Developing Gale/Storm In the high seas and offshore forecasts, a headline used in the warnings section to indicate that gale/storm force winds are not now occurring but are…
  78. development The sum total of events that contribute to the progressive elaboration of an organism. The two major aspects of development are growth and differentiation.
  79. Development Rights Development rights give property owners the right to develop land in ways that comply with local land use regulation.
  80. developmental and reproductive effects Effects caused by some physical, chemical, or biological agent, such as radiation, to the formation and development of a fetus, that results in one or…
  81. deviation 1. An alteration from the typical form, function or behaviour. Mutation or stress are the common reasons behind deviation. 2.
  82. Deviator stress The difference between the major and minor principal stresses in a triaxial test.
  83. Dew Moisture in the air that condenses on solid surfaces when the air is saturated with water vapor.
  84. Dew point The temperature to which air with a given quantity of water vapor must be cooled to cause condensation of the vapor in the air.
  85. Dew Point Depression The difference in degrees between the air temperature and the dew point.
  86. Dew Point Front A narrow zone (mesoscale feature) of extremely sharp moisture gradient and little temperature gradient. It separates moist air from dry air.
  87. Dewatering The separation of free water from the solids portion of spent mash, sludge, or whole stillage by screening, centrifuging, filter pressing, or other means.
  88. DEWP On a buoy report, the dewpoint temperature taken at the same height as the air temperature measurement.
  89. Dewpoint The temperature to which air must be cooled, at constant pressure and water vapor content, in order for saturation or condensation to occur; the…
  90. dextrin An intermediate polysaccharide compound resulting from the hydrolysis of starch to maltose by amylase enzymes.
  91. DFUS Diffuse
  92. dG - dC tailing See: complementary homopolymeric tailing.
  93. DGGE See: denaturing gradient gel electrophoresis.
  94. dGTP Abbreviation for deoxyguanosine 5'-triphosphate. dGTP is required for DNA synthesis since it is a direct precursor molecule. See: guanosine, guanylic acid.
  95. DHRO Diversity and Human Resources Office.
  96. DI durability index.
  97. di-deoxynucleotide (Abbreviations: ddNTP,didN). A synthetic deoxynucleotide that lacks a 3'-hydroxyl group, and is thus unable to form the 3'?
  98. Diabatic A process which occurs with the addition or loss of heat. The opposite of adiabatic.
  99. Diabetes Any of several diseases in which the kidneys make a large amount of urine. Diabetes usually refers to diabetes mellitus in which there is also a high…
  100. diabetes mellitus (dye-a-BEE-teez MEL-ih-tus) A group of disorders in which there is a defect in the transfer of glucose (sugar) from the bloodstream into cells, leading to…