or dry in cylindrical pods. In order to provide quick access for servicing and placement, there is a trend to use trays of dry batteries in cylindrical pods. Externally carried batteries can also be used as droppable ballasts in the event of an emergency requiring additional buoyancy to surface Silver-zinc or silver-cadmium batteries provide three to five times as much energy per pound as lead-acid batteries and are employed where mission requirements justify their added costs. For endurances beyond 50 hr, fuel cells, radio isotopes, and nuclear reactor can be employed at much greater cost. Most submersibles have maximum speeds in the range of (330 )3-5 knots (1.5-2.6m/s) and have modest power needs for propulsion. Doubling the speed would require at least eight times more power. Sensors These instruments are required on small submersibles to determine position, communicate with other units. and make observations of the environment both for a record and while performing work. Typical radio on a small oceanographic submersible include radio telephone, underwater telephone, external lighting, magnetic recorder, movie camera(carried internal in the pressure hull for viewing through sight ports), magnetic recorder, directional gyro, depth sounder Life support systems All submersibles require life support systems, and those on the small oceanographic type take into consideration the following services for atmospheric control and monitoring breathing mixture supply system; carbon dioxide removal system; hydrogen, carbon monoxide, and toxin removal systems; air purification and filtering systems, atmospheric monitoring system; and emergency breathing supply system. Most systems on the small submersibles are relatively simple and emphasize the removal of carbon dioxide and the supply of replacement oxygen. Air inside the submersible is drawn continuously through an absorbent system composed of activated harcoal to remove odors and of lithium hydroxide and baralyme to remove Oz so that its concentration never exceeds about 0. 1%. The internal hull pressure, displayed on an aneroid barometer and sensitive altimeter, decreases slightly as CO2 removal equipment to maintain the pressure at I atm(101 325Nm2) Both O and CO2 content are constantly monitored by meters Submersibles have proved to be a significant tool in many commercial applications and for scientific research and their abundance and utilization is steadily increasing ( From"McGraw- Hill Encyclopedia of Science and Technology", Vol 9. 1982) Technical Terms 1. oceanographic submersible海洋考察潜7. coral珊瑚 水器 8. geology地质 submersible潜水器,可潜器 ology生物 sampling取样 10. handling gear for launching and retrieval 3. undersea vehicle潜水船(器) 起吊回收装置 4. offshore oil industry近海(海洋)石油11. logistic and maintenance support后勤维 工业 护保障(设施) 5. cable burial电缆埋设 12. heavy sea大风浪 6. salvage救捞 13. manipulator机械手or dry in cylindrical pods. In order to provide quick access for servicing and placement, there is a trend to use trays of dry batteries in cylindrical pods. Externally carried batteries can also be used as droppable ballasts in the event of an emergency requiring additional buoyancy to surface. Silver-zinc or silver-cadmium batteries provide three to five times as much energy per pound as lead-acid batteries and are employed where mission requirements justify their added costs. For endurances beyond 50 hr, fuel cells, radio isotopes, and nuclear reactor can be employed at much greater cost. Most submersibles have maximum speeds in the range of (.330.)3—5 knots (1.5—2.6m/s) and have modest power needs for propulsion. Doubling the speed would require at least eight times more power.3 Sensors These instruments are required on small submersibles to determine position, communicate with other units, and make observations of the environment both for a record and while performing work. Typical radio on a small oceanographic submersible include radio telephone, underwater telephone, external lighting, magnetic recorder, movie camera (carried internal in the pressure hull for viewing through sight ports), magnetic recorder, directional gyro, depth sounder, and manometer depth indicator. Life support systems All submersibles require life support systems, and those on the small oceanographic type take into consideration the following services for atmospheric control and monitoring: breathing mixture supply system; carbon dioxide removal system; hydrogen, carbon monoxide, and toxin removal systems; air purification and filtering systems; atmospheric monitoring system; and emergency breathing supply system. Most systems on the small submersibles are relatively simple and emphasize the removal of carbon dioxide and the supply of replacement oxygen. Air inside the submersible is drawn continuously through an absorbent system composed of activated charcoal to remove odors and of lithium hydroxide and boralyme to remove CO2 so that its concentration never exceeds about 0.1%.4 The internal hull pressure, displayed on an aneroid barometer and sensitive altimeter, decreases slightly as CO2 removal equipment to maintain the pressure at 1 atm (101 325Nm2 ) .5 Both O2 and CO2 content are constantly monitored by meters. Submersibles have proved to be a significant tool in many commercial applications and for scientific research and their abundance and utilization is steadily increasing. （From “McGraw- Hill Encyclopedia of Science and Technology”, Vol. 9. 1982） Technical Terms 1. oceanographic submersible 海洋考察潜 水器 submersible 潜水器，可潜器 2. sampling 取样 3. undersea vehicle 潜水船（器） 4. offshore oil industry 近海（海洋）石油 工业 5. cable burial 电缆埋设 6. salvage 救捞 7. coral 珊瑚 8. geology 地质 9. biology 生物 10. handling gear for launching and retrieval 起吊回收装置 11. logistic and maintenance support 后勤维 护保障（设施） 12. heavy sea 大风浪 13. manipulator 机械手