HYDROLOGICAL REGIME, objective change of state of water object in time (a level and a discharge of water, the ice phenomena, etc.), stipulated primarily climatic features of the given basin. The natural hydrological regime is quite often essentially recasted under influence of economic activities of the person.

HYDROLOGY (from gidro... And... logija), the science investigator natural waters, the phenomena and processes, in them weeping. A subject of study of hydrology - all kinds of waters of a hydrosphere in oceans, seas, the rivers, lakes, water reservoirs, bogs, soil and underground waters. It is divided on oceanology and land hydrology. Investigates a hydrologic cycle in a nature, influence on him of a human activity and steering of a mode of water objects and a water relationships of separate terrains; carries out the analysis of hydrological elements for separate terrains and the Earth as a whole; the forecast of a condition and intelligent use of water resources assesss also; uses the methods used in geography, physics and other sciences.

LAND HYDROLOGY, the science investigator surface waters of a dry matter: the rivers, lakes, water reservoirs, bogs and icehouses; section of hydrology. The land hydrology on objects of study is sectioned into river hydrology (the doctrine about the rivers - potamologiju), a limnology (ozerovedenie), telmathology.

HYDROLOCATION (from gidro... And an armour. locatio - disposition), position finding and travelling speeds of submerged objects through the sound signals which are radiated objects (a passive detection and ranging, shumopelengatsija) or as a result of reflectance from them specially sent signals (an active detection and ranging). On rate of propagation of a note in water and to period between the moments of radiance and method of a sound signal determine distance up to object, and on a direction of arrival of a radioecho - a direction of object. A hydrolocation apply to detection of the ships (in particular, submersibles), shoals of a fish, probe of a bottom, etc.

HYDROMAGNETIC DYNAMO, intensifying or maintenance in a stationary state of a magnetic field hydrodynamic motion of a conducting medium (plasma, a liquid). The mechanism of a hydromagnetic dynamo is similar to generation of a current flow and a magnetic field in the dynamo self-excited. Implementation of a hydromagnetic dynamo in entrails of asters and some planets (including. The Earth) explain exaltation for them a natural magnetic field (see. Hydromagnetics).

HYDROMETALLURGY (from gidro... And metallurgy), extraction of metals from ores, concentrates and waste products of different manufactures through water solutions of chemical reactants (leaching) with consequent secretion of metals from solutions (napr., case hardening, an electrolysis). The hydrometallurgy has received broad application in manufacture of many metals.

GIDROMETEOIZDAT, publishing house, Saint Petersburg (branch in Moscow). It is based in 1934. The literature on meteorology, hydrology, oceanology.

The HYDROMETEOROLOGICAL SERVICE of Russian Federation (GMS), ensures a national economy with the information and forecasts in range of meteorology, a climatology, an agrometeorology, hydrology and marine meteorology. The network of meteorological and hydrological stations enters into it, observatories and so forth. It is headed by the Federal service of Russia on a hydrometeorology and environmental monitoring.

The HYDROMETEOROLOGICAL CENTRE of the Russian Federation research (hydrometeorological centre of Russia), is based in 1965 on the basis Central institute of forecasts (it is based in 1930). All kinds of meteorological, hydrological, agrometeorological forecasts. One of the centres of the World weather service.

HYDROMETEORS, synonym for a rainfall of any stem. A rainfall secreted directly from air above ground and on subjects (dew, hoarfrost, hoarfrost and so forth) more often are implied.

HYDROMETRY (from gidro... And... metrija), section of hydrology in which are developed primarily a technique of study of a mode of seas, the rivers and lakes, channels and water reservoirs, and also ways of supervision of the phenomena defining this mode (measurement of speed of a water-course, his level, depth, etc.).

HYDRO-MECHANIZATION, way of mechanization of earth, mountain and other activities at which all or a main body of production processes are carried out by driving water deluge.

HYDROMECHANICS, the section of mechanics investigator balance and motion of liquids, and also interaction of a liquid with bodies submersed or driving in her. It is sectioned into hydrodynamics and a hydrostatics.

WATER DUTY (from gidro... And an armour. modulus - a measure), average discharge of an irrigating water (in ë) on 1 ga crops of a crop for 1 seconds. Knowing a water duty and the area of a raflux plot, it is possible to define consumption of water by him on 1 watering and all irrigation season. The water duty enables to compare a discharge of water of a source of an irrigation to requirements for her of agricultural plants and to constitute the water use schedule.

JET GUN (from gidro... And English monitor - a waterjet), the apparatus for building potent water jets with the purpose of destruction and conveyance of rocks. For the first time it is applied in Russia on gravel mines of Ural (1830).

HYDRAULIC CLUTCH (from gidro... And a clutch), a hydrodynamic transmission - the mechanism relaying rotary movement from a drive shaft to conducted. Will consist of an impeller pump and the water-wheel which blade sprockets are connivent and will derivate toroobraznuju a cavity which is filled in with working fluid. Ministers for a torque transfer without his change (loss in a hydraulic clutch are not taken into account). It is applied in drives of drill rigs, feed pumps and induced-draft fans teploenergotsentralej, etc.

HYDRONEPHROSIS (from gidro... And grech. nephros - a kidney), a stretching renal pelvises and calyxes owing to violation of out flux wet. Complication - an atrophy of a kidney and its metamorphosis into a cyst. The causes: a nephrolithiasis, a tumour, a scar of a ureter. Treatment operating.

HYDRAULIC FILL, hydrotechnical construction for warehousing rock refuse, washery refuses and other materials delivered by a means of a hydro-mechanization. Receiving ability - a little bit one million in m3, an altitude - tens meters.

HYDROCLEARING, clearing of engine fuels, oils and other petroleum of impurity of organic derivative sulfur, oxygen, nitrogen. Implements action of hydrogen at the presence of catalysts at 250-415 °S and pressure 1-10 MPa; thus impurity turn to saturated hydrocarbons and readily-removable H2S, H2O, NH3.

HYDROSTATIC TRANSMISSION, the same, that a hydraulic transmission.