www射-国产免费一级-欧美福利-亚洲成人福利-成人一区在线观看-亚州成人

US EUROPE AFRICA ASIA 中文
Business / Green China

Beijing-area air better than before

By Cheng Yingqi (China Daily) Updated: 2014-03-03 03:54

The pollution that hit Hebei province, Beijing and Tianjin in the past week was less severe than last year's incident, monitoring results revealed.

From Feb 20 to 26, Beijing, Tianjin and Hebei were shrouded in smog.

However, environment-monitoring results of the Chinese Academy of Sciences showed that the average concentration of PM2.5 — fine particulate matter with a diameter less than 2.5 microns that can lodge in the lungs — was 11 percent less than it was when smog hit the region in spring 2013, and the peak concentration decreased by 16.4 percent.

"The concentration of pollutants in the smog decreased by 20 to 30 percent in general over the last year," said Wang Yuesi, a researcher from the Institute of Atmospheric Physics under the Chinese Academy of Sciences.

Wang was speaking on Saturday at a forum in Beijing held by the Chinese Academy of Sciences, which discussed the cause of the smog.

The institute monitored the concentration of PM2.5 and other pollutants across the country, with 23 monitoring stations in North China. The comparison was based on data collected in January and February this year and January 2013, when severe pollution lasted nearly a month in North China.

Both of these smog events had similar climatic conditions, Wang said.

"The monitoring results show that the emergency measures taken to cope with air pollution were effective. But the effect may not be so obvious to the general public because the PM2.5 concentration still caused a deterioration in visibility," he said.

Visibility in the smog was 2 kilometers, while Wang said the visibility will not be improved unless the PM2.5 concentration falls to less than 100 micrograms per cubic meter. In February, it was 230 mg per cubic meter.

Beijing's contingency plan includes forcing nearby plants to cut their production.

However, Wang said that only long-term solutions will end the pollution.

"The major PM2.5 source comes from coal power stations," he said. "The overall area of Beijing, Tianjin and Hebei accounts for some 0.05 percent of the world, while this region consumes 11 percent of its coal, so you don't have to use your imagination to understand why we are suffering from air pollution. We are living inside a huge chimney."

He Hong, a researcher at the Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, said: "Our research shows that 'second particles' contribute around 60 percent to the formation of PM2.5 in Beijing and Tianjin."

Second particles are pollutants generated by chemical reactions between different pollutants released into the atmosphere.

"As a result, reducing the emissions of oxynitride and oxysulfide from coal fuel and vehicles is necessary," He said.

However, due to the complex chemical reactions, scientists are not sure about the exact contributing factors of smog. To understand better, the Chinese Academy of Sciences will apply for construction in 2016 of a "smog chamber" to simulate pollution conditions.

Hot Topics

Editor's Picks
...
主站蜘蛛池模板: 亚洲精选在线观看 | 理论片我不卡在线观看 | 成人18网址在线观看 | 青青青免费手机版视频在线观看 | 中文字幕一区二区三区精彩视频 | 欧美三级超在线视频 | 国产三级小视频在线观看 | 九九大香尹人视频免费 | 九九久久久 | 日本一级毛片高清免费观看视频 | 波多野结衣一区在线 | 伊在人亚洲香蕉精品区 | 性色aⅴ在线观看swag | 久久99亚洲精品久久久久99 | 嫩草影院在线观看网站成人 | 国产精品激情丝袜美女 | 孕妇xxxx视频在线 | 扒开双腿猛进入爽爽在线观看 | 久草福利在线观看 | 久草在线资源网站 | 国产成人精品曰本亚洲77美色 | 亚洲国产精品成人久久 | 成人免费视频软件网站 | 三级视频在线播放线观看 | 大胆gogo999亚洲肉体艺术 | 欧美日韩国产人成在线观看 | 天天噜夜夜操 | 成人毛片国产a | 日本在线视频不卡 | www.欧美xxxx | 天天看a| 国产欧美日韩精品第二区 | 亚洲精品影院久久久久久 | 中文字幕乱码中文乱码51精品 | 国产91精选在线观看网站 | 久久精品国产这里是免费 | 国产一区第一页 | 成人三级精品视频在线观看 | 96精品视频在线播放免费观看 | 国产精品亚洲第五区在线 | a级片在线免费观看 |