The seismological characteristics of the 15 February 2013 Chelyabinsk bolide explosion are investigated based on seismograms recorded at 50 stations with epicentral distances ranging from 229 to 4324 km. By using 8–2...The seismological characteristics of the 15 February 2013 Chelyabinsk bolide explosion are investigated based on seismograms recorded at 50 stations with epicentral distances ranging from 229 to 4324 km. By using 8–25 s vertical-component Rayleigh waveforms,we obtain a surface-wave magnitude of 4.17±0.31 for this event. According to the relationship among the Rayleigh-wave magnitude,burst height and explosive yield, the explosion yield is estimated to be 686 kt. Using a single-force source to fit the observed Rayleigh waveforms, we obtain a single force of 1.03×10^(12) N, which is equivalent to the impact from the shock wave generated by the bolide explosion.展开更多
With nylon mesh bags, the decomposition and nutrients release characteristics of two kinds of green manure crops, February orchid （Orychophragmus violaceus） and Hair Vetch （Vicia villosa Roth）, were investigated i...With nylon mesh bags, the decomposition and nutrients release characteristics of two kinds of green manure crops, February orchid （Orychophragmus violaceus） and Hair Vetch （Vicia villosa Roth）, were investigated in this study. The results showed that these two kinds of green manure crops were decomposed rapidly in the first 14 days, and then decomposed slowly. After 80 days of incubation, the decomposition rates of February orchid and Hair Vetch were 66.92% and 63.12%, respectively. Different nutrients had different release rates from the green manures. Nitrogen （N） and potassium （K） were released rapidly in the initial 7 days, and phosphorus （P） was released steadily in the 80 days of incubation. In the two kinds of green manures, the release rates all ranked as K＇s〉N＇s〉P＇s. The release rates of nutrients, especially P （P〈0.05）, of February orchid were higher than those of Hair Vetch.展开更多
Illustration All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in ...Illustration All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.展开更多
All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China...All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geoohysics, China Earthquake Administration.展开更多
The Moroccan Spring in 2011 has been a golden opportunity for Moroccan women to put their country on the democratization track. Their decision to take an integral part in all aspects of the uprisings stems from their ...The Moroccan Spring in 2011 has been a golden opportunity for Moroccan women to put their country on the democratization track. Their decision to take an integral part in all aspects of the uprisings stems from their belief that their participation and contribution are necessary for any potential democratic changes that would undoubtedly secure and bring them more rights. However, the appointment of only one female minister in the first Islamist-led government and the reluctance to implement the provisions of the new constitution, namely the issue of gender parity, are but two of the new alarming examples that have disappointed Moroccan women. Based on interviews with women＇s movement organizations＇ leaders and 20 February Movement （20-FMVT） female activists and through following the development of the Arab Spring in Morocco in particular and in the Middle Eastern ＆ Northern Africa region in general, this paper considers the different roles, specificity, and gains of Moroccan women during and after the so-called Moroccan Spring. The paper argues that despite their limited gains in the aftermath of this momentum, Moroccan women managed once again to prove their agency and ability to change laws and instigate reforms.展开更多
基金supported by the National Key Research and Development Program of China (grant 2017YFC0601206)the National Natural Science Foundation of China (grants 41674060 and 41630210)
文摘The seismological characteristics of the 15 February 2013 Chelyabinsk bolide explosion are investigated based on seismograms recorded at 50 stations with epicentral distances ranging from 229 to 4324 km. By using 8–25 s vertical-component Rayleigh waveforms,we obtain a surface-wave magnitude of 4.17±0.31 for this event. According to the relationship among the Rayleigh-wave magnitude,burst height and explosive yield, the explosion yield is estimated to be 686 kt. Using a single-force source to fit the observed Rayleigh waveforms, we obtain a single force of 1.03×10^(12) N, which is equivalent to the impact from the shock wave generated by the bolide explosion.
文摘With nylon mesh bags, the decomposition and nutrients release characteristics of two kinds of green manure crops, February orchid （Orychophragmus violaceus） and Hair Vetch （Vicia villosa Roth）, were investigated in this study. The results showed that these two kinds of green manure crops were decomposed rapidly in the first 14 days, and then decomposed slowly. After 80 days of incubation, the decomposition rates of February orchid and Hair Vetch were 66.92% and 63.12%, respectively. Different nutrients had different release rates from the green manures. Nitrogen （N） and potassium （K） were released rapidly in the initial 7 days, and phosphorus （P） was released steadily in the 80 days of incubation. In the two kinds of green manures, the release rates all ranked as K＇s〉N＇s〉P＇s. The release rates of nutrients, especially P （P〈0.05）, of February orchid were higher than those of Hair Vetch.
文摘Illustration All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.
文摘All the data in this catalog are chosen from the ＂Preliminary Seismological Report of Chinese Seismic Stations＂ （Its abbreviation is ＂Monthly Report＂）. The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The ＂Monthly Report＂ is monthly compiled by the Ninth Section of Institute of Geoohysics, China Earthquake Administration.
文摘The Moroccan Spring in 2011 has been a golden opportunity for Moroccan women to put their country on the democratization track. Their decision to take an integral part in all aspects of the uprisings stems from their belief that their participation and contribution are necessary for any potential democratic changes that would undoubtedly secure and bring them more rights. However, the appointment of only one female minister in the first Islamist-led government and the reluctance to implement the provisions of the new constitution, namely the issue of gender parity, are but two of the new alarming examples that have disappointed Moroccan women. Based on interviews with women＇s movement organizations＇ leaders and 20 February Movement （20-FMVT） female activists and through following the development of the Arab Spring in Morocco in particular and in the Middle Eastern ＆ Northern Africa region in general, this paper considers the different roles, specificity, and gains of Moroccan women during and after the so-called Moroccan Spring. The paper argues that despite their limited gains in the aftermath of this momentum, Moroccan women managed once again to prove their agency and ability to change laws and instigate reforms.
