《保护臭氧层》PPT课件.ppt
《《保护臭氧层》PPT课件.ppt》由会员分享,可在线阅读,更多相关《《保护臭氧层》PPT课件.ppt(28页珍藏版)》请在三一办公上搜索。
1、保護臭氧層OZONE LAYER PROTECTION,臭氣層 OZONE LAYER,在離地面15至35 公里的平流層內,由臭氧氣體形成的一道屏障A shield of ozone gas in the stratosphere between 15 to 35 km它能吸收紫外光的輻射,因此可阻擋來自太陽有害光線的滲透 It absorbs ultraviolet(UV)radiation,thus inhibiting penetration of harmful UV rays from the sun一九七五年,科學家己測到每年春季,南極洲上空豐厚的臭氧層呈現急劇轉薄的現象 In 1
2、975,scientists have detected a severe drop in ozone abundance in the layer over Antarctica each spring,臭氣層 OZONE LAYER,一九八七年,發現南極洲上空的臭氧層消失了一半,出現一個大缺口,面積相等於美國總面積的兩倍 In 1987,half of Antarcticas ozone was found to have disappeared over a region twice the size of US,creating an enormous“hole”in the ozon
3、e layer當地球表面受到更多紫外光的輻射時:With more UV radiation reaching the earths surface:皮膚癌、白內障等發病率增加,人體免疫系統受損Increased incidence of skin cancer,eye cataracts,damage to human immune system地球生態系統受破壞Damage to the ecology of the earth臭氧層的損耗,乃由損耗臭氧層的物質所造成Ozone depletion is caused by the ozone depleting substances,消耗
4、臭氧層的物質OZONE DEPLETING SUBSTANCES(ODSs),是人造化學化合物-鹵烴、其中包括碳和鹵素(氟、氯或溴)原子 A family of man-made chemical compounds-halocarbons,containing carbon and halogen(Fluorine,Chlorine or Bromine)atoms ODSs 性質極其穩定,延續長久,存在於大氣下層,可飄浮至離地面16公里的平流層 Extremely stable and a long life span in the lower atmosphere allowing tr
5、ansport to the stratosphere situated 16 km above the ground level 在平流層內ODSs遭紫外光作用而分解,釋出氯原子與臭氧作用而產生氧分子,因而降低平流層內臭氧濃度 In the stratosphere,ODSs are broken down by the action of ultraviolet light,releasing chlorine atoms,reacting with ozone to produce molecular oxygen,thus reducing the ozone concentratio
6、n of the stratospheric ozone layer.,消耗臭氧層物質包括ODSs include含氯氟氫 ChloroFluoroCarbons(CFC)鹵代碳氫化合物(哈龍)HALogenated hydrocarbON(HALON)甲基氯仿(1,1,1-三氯乙烷)Methyl Chloroform(1,1,1-trichloroethane)甲基溴 Methyl Bromide四氯化碳(四氯甲烷)Carbon tetrachloride(Tetrachloromethane)含溴氟氫 HydroBromoFluoroCarbons(HBFC)含氯氟氫 HydroChlor
7、oFluoroCarbons(HCFC),消耗臭氧層的物質OZONE DEPLETING SUBSTANCES(ODSs),消耗臭氧層物質的用途 APPLICATION OF ODS,CFC,HCFC:供冷氣工程和製冷工業用作冷卻劑(CFC-11,CFC-12 and HCFC-22)Used as refrigerants in the air-conditioning and refrigeration industry作為噴霧劑的推進劑(CFC-11 and CFC-12)Used as propellants for aerosol sprays供發泡膠工業用作發泡劑(CFC-11 a
8、nd CFC-12)Used as blowing agents for foam industry供電子工業用作清潔劑(CFC-113)Used as cleaning agents in electronic industry哈龍 HALONS手提滅火器內所用的哈龍(Halons 1211)BCF used in portable fire extinguisher固定防火裝置內所用的哈龍(Halons 1301)BTM used in fixed fire protection installations,消耗臭氧層物質的用途 APPLICATION OF ODS,三氯乙烷 1,1,1-
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 保护臭氧层 保护 臭氧层 PPT 课件
链接地址:https://www.31ppt.com/p-5463626.html