| 释义 |
dead space
dead space1. An area within the maximum range of a weapon, radar, or observer, which cannot be covered by fire or observation from a particular position because of intervening obstacles, the nature of the ground, or the characteristics of the trajectory, or the limitations of the pointing capabilities of the weapon.
2. An area or zone which is within range of a radio transmitter, but in which a signal is not received.
3. The volume of space above and around a gun or guided missile system into which it cannot fire because of mechanical or electronic limitations.dead space
dead space[′ded ‚spās] (anatomy) The space in the trachea, bronchi, and other air passages which contains air that does not reach the alveoli during respiration, the amount of air being about 140 milliliters. Also known as anatomical dead space. (medicine) A cavity left after closure of a wound. (physiology) A calculated expression of the anatomical dead space plus whatever degree of overventilation or underperfusion is present; it is alleged to reflect the relationship of ventilation to pulmonary capillary perfusion. Also known as physiological dead space. (thermodynamics) A space filled with gas whose temperature differs from that of the main body of gas, such as the gas in the capillary tube of a constant-volume gas thermometer. dead space i. An area within the maximum range of a weapon, radar, or observer that cannot be covered by fire or observation from a particular position because of intervening obstacles, the nature of the ground, the characteristics of the trajectory, or the limitations of the pointing capabilities of the weapons.
ii. An area or zone that is within range of a radio transmitter but in which a signal is not received.
iii. The volume of space above and around a gun or guided missile system into which it cannot fire because of mechanical or electronic limitations.
iv. Dead spots in radio-range reception areas over transmitting stations similar to the cone of silence but lacking normal characteristics like buildup, dead spots, surges, and fades. This phenomenon is likely to be caused by flights over mountains, areas of ore deposits, and other factors. See also cone of silence.
v. The area located between the limit of the surface wave and the point of reception of the first sky wave. It is most common in the HF (high frequency) frequency range. Also called the skip zone.dead space
dead space 1. a space remaining in the tissues as a result of failure of proper closure of surgical or other wounds, permitting the accumulation of blood or serum.2. the portions of the respiratory tract that are ventilated but not perfused by pulmonary circulation.alveolar dead space the difference between anatomical dead space and physiologic dead space, representing the space in alveoli occupied by air that does not participate in oxygen–carbon dioxide exchange (ventilation" >alveolar ventilation). It varies in different parts of the lungs and under different conditions.anatomical dead space the airways of the mouth, nose, pharynx, larynx, trachea, bronchi, and bronchioles.equipment dead space the volume of equipment that results in rebreathing of gases.physiologic dead space the sum of the anatomic and alveolar dead spaces; its volume (VD) is determined by measuring the partial pressure of carbon dioxide in a sample of exhaled gas (PECO2) and in the arterial blood (PaCO2) and (with tidal volume of VT) using the formula VD/VT = (PaCO2−PECO2)/PaCO2.dead space1. a cavity, potential or real, remaining after the closure of a wound that is not obliterated by the operative technique; 2. Physiology All non-air exchanging spaces of the upper respiratory tract; there are ± 2.0 ml of ‘dead space’/kg body weight—i.e., a 70-kg person has 140–150 ml of dead space in the oronasopharynx, bronchi, and bronchioles
Therapeutics That part of a syringe’s tip and needle that contains medication that cannot be administered; dead space is very important in insulin therapy, and for drugs in which the syringe has < 0.5 mL capacitydead space Clinical therapeutics That part of a syringe's tip and needle that contains medication that can't be administered; DS is very important in insulin therapy, and for medications where the syringe has < 0.5 mL capacitydead space (ded spās) A cavity, potential or real, remaining after the closure of a wound that is not obliterated by the operative technique.
See: anatomic dead space, physiologic dead spacedead space the air in trachea, bronchi and bronchioles that does not take part in gaseous exchange. Of each breath of 500 cm3, only about half of the air reaches the alveoli.dead space (ded spās) A cavity, potential or real, remaining after the closure of a wound that is not obliterated by the operative technique.AcronymsSeedata setThesaurusSeespace |