In-situ measurement of atmospheric CO_2 was made at the top of the Waliguan Mountain(36°17′N,100°54′E,3816 m asl).where the air is not directly affected by the local anthropogenic and natural sources,by us...In-situ measurement of atmospheric CO_2 was made at the top of the Waliguan Mountain(36°17′N,100°54′E,3816 m asl).where the air is not directly affected by the local anthropogenic and natural sources,by using a nondispersive infrared(NDIR)analyzer and following the procedures proposed by WMO.The CO_2 in the flask samples collected on the mountain was also analyzed in a laboratory.The measurements uncover the daily,monthly and seasonal variabilities and the baseline level of the CO_2 in the air over the“clean”area of Chinese hinterland.Results suggest that the CO_2 concentration over the East Asia continent has evident periodical variation,similar to that of global distribution.In 1992,an annual mean baseline CO_2 concentration of 356.4 ppm over the continent was obtained.The annual mean val- ue was 357.2 ppm for 1993.Some relationships between the CO_2 concentration at Waliguan and the weather conditions, especially,wind speed and direction are found through the observation.展开更多
The reduction of low-concentration carbon dioxide with water to organic fuels is still a huge challenge. In this study, we successfully designed the partially oxidized cobalt nanoparticles coated by the nitrogendoped ...The reduction of low-concentration carbon dioxide with water to organic fuels is still a huge challenge. In this study, we successfully designed the partially oxidized cobalt nanoparticles coated by the nitrogendoped carbon layer(Co@NC) of 2-8 nm via a facile method and then interspersed with different amount of Pt nanoparticles. The Co@NC decorated with 1 wt% Pt exhibits the best ability for COreduction to CHand a CHproduction rate of 14.4 μmol·g·his achieved. It is worth noting that the system is carried out under low-concentration CO(400 ppm) circumstance without any sacrificial agent, which could be meaningful to the design of catalysts for atmospheric COreduction.展开更多
There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional a...There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73.展开更多
基金This study is supported by the National Science and Technology Commission of China.
文摘In-situ measurement of atmospheric CO_2 was made at the top of the Waliguan Mountain(36°17′N,100°54′E,3816 m asl).where the air is not directly affected by the local anthropogenic and natural sources,by using a nondispersive infrared(NDIR)analyzer and following the procedures proposed by WMO.The CO_2 in the flask samples collected on the mountain was also analyzed in a laboratory.The measurements uncover the daily,monthly and seasonal variabilities and the baseline level of the CO_2 in the air over the“clean”area of Chinese hinterland.Results suggest that the CO_2 concentration over the East Asia continent has evident periodical variation,similar to that of global distribution.In 1992,an annual mean baseline CO_2 concentration of 356.4 ppm over the continent was obtained.The annual mean val- ue was 357.2 ppm for 1993.Some relationships between the CO_2 concentration at Waliguan and the weather conditions, especially,wind speed and direction are found through the observation.
基金financially supported by the National Natural Science Foundation of China(Nos.51772312 and 51472260)the Environmental Functional Materials Innovation Team of Ministry of Education(IRT 16R49)the International Joint Laboratory on Resource Chemistry(IJLRC)
文摘The reduction of low-concentration carbon dioxide with water to organic fuels is still a huge challenge. In this study, we successfully designed the partially oxidized cobalt nanoparticles coated by the nitrogendoped carbon layer(Co@NC) of 2-8 nm via a facile method and then interspersed with different amount of Pt nanoparticles. The Co@NC decorated with 1 wt% Pt exhibits the best ability for COreduction to CHand a CHproduction rate of 14.4 μmol·g·his achieved. It is worth noting that the system is carried out under low-concentration CO(400 ppm) circumstance without any sacrificial agent, which could be meaningful to the design of catalysts for atmospheric COreduction.
文摘There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73.
