An increasing number of geological hazards along high-speed railways on the Qinghai‒Tibetan Plateau have occurred and have resulted in a profound influence on old infrastructure,which has attracted increasing attentio...An increasing number of geological hazards along high-speed railways on the Qinghai‒Tibetan Plateau have occurred and have resulted in a profound influence on old infrastructure,which has attracted increasing attention.The landslide event that occurred on September 15,2022,in Jiujiawan village,Xining city,Qinghai Province,is a typical case.Based on field investigations and remote sensing interpretations,a comprehensive analysis was conducted on the landslide.Additionally,the potential secondary failure of the current Jiujiawan landslide was assessed using Fast Lagrangian Analysis of Continua in Three Dimensions(FLAC3D).Based on the application of the small baseline subset-interferometric synthetic aperture radar(SBAS-InSAR)technique to SAR images from February 24,2017 to September 14,2022,a significant westward horizontal deformation was found to have been formed prior to the occurrence of the landslide.The maximum annual average deformation rate in the line of sight(LOS)direction reached-45 mm/yr,with a maximum cumulative deformation of-178 mm.This value was consistent with the continual increase in annual precipitation(2.51 mm/yr)prior to the occurrence of the landslide.The accumulated precipitation before the landslide was 279.8 mm,accounting for 54.2%of the total annual precipitation,with a particularly notable surge in monthly precipitation observed during August(250.3 mm).Additionally,the occurrence of a seismic event with a magnitude of Ms 6.9 in Menyuan County,80 km away from Xining,could be a potential triggering factor to the landslide,as evidenced by an abrupt subsidence alteration observed prior to and following the earthquake.The maximum subsidence in the line of sight(LOS)direction exceeded 11 mm,exhibiting a highly consistent spatial distribution with the occurrence range of landslides.These results suggest that the Jiujiawan landslide was likely induced by earthquake events in the early stage and heavy rainfall in the later stage.The FLAC3D numerical simulation show that after the landslide,the slope remained marginally stable under natural conditions;however,it is susceptible to reactivation with heavy rainfall.展开更多
In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, whi...In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway.展开更多
为探讨电子束辐照对大豆品质的影响,以1.09、2.99、5.76、7.89、8.97 k Gy吸收剂量的电子束对大豆进行辐照处理,研究电子束辐照对大豆含油率、蛋白质含量、氨基酸的组成及含量、酸价、过氧化值、蛋白质溶解度及尿素酶活性的影响。结果表...为探讨电子束辐照对大豆品质的影响,以1.09、2.99、5.76、7.89、8.97 k Gy吸收剂量的电子束对大豆进行辐照处理,研究电子束辐照对大豆含油率、蛋白质含量、氨基酸的组成及含量、酸价、过氧化值、蛋白质溶解度及尿素酶活性的影响。结果表明,电子束辐照对大豆含油率、蛋白含量、氨基酸组成及含量影响较小;5.76 k Gy时,酸价降低了37.3%,8.97 k Gy时过氧化值及尿素酶活性分别降低37.5%和11.36%。综合分析可知,5.76 k Gy是大豆的电子束辐照储藏适宜剂量。本研究结果为电子束辐照在大豆储藏与加工中的应用提供了参考。展开更多
以玉米和赭曲霉毒素A纯品为研究对象,研究了电子束辐照对玉米品质的影响,探讨了辐照对赭曲霉毒素A的降解效果。结果表明,电子束辐照对玉米的常规营养成分、氨基酸含量及其组成几乎没有影响,但5kGy剂量的电子束辐照对玉米脂肪酸组成及脂...以玉米和赭曲霉毒素A纯品为研究对象,研究了电子束辐照对玉米品质的影响,探讨了辐照对赭曲霉毒素A的降解效果。结果表明,电子束辐照对玉米的常规营养成分、氨基酸含量及其组成几乎没有影响,但5kGy剂量的电子束辐照对玉米脂肪酸组成及脂肪酸值有显著影响。赭曲霉毒素A的降解率随着辐照剂量的增加而提高,在3kGy的辐照剂量下,初始质量浓度为310.0μg/L的赭曲霉毒素A降解率为49.55%,当辐照剂量增大到5 k Gy时,降解率达到93.19%,此后降解率随辐照剂量增加的趋势变缓。因此,3~5 k Gy剂量的电子束辐照不会降低玉米品质,并能够降解赭曲霉毒素A。展开更多
基金supported by the Natural Science Foundation of Qinghai Province,China(No.2024-SF-129).
文摘An increasing number of geological hazards along high-speed railways on the Qinghai‒Tibetan Plateau have occurred and have resulted in a profound influence on old infrastructure,which has attracted increasing attention.The landslide event that occurred on September 15,2022,in Jiujiawan village,Xining city,Qinghai Province,is a typical case.Based on field investigations and remote sensing interpretations,a comprehensive analysis was conducted on the landslide.Additionally,the potential secondary failure of the current Jiujiawan landslide was assessed using Fast Lagrangian Analysis of Continua in Three Dimensions(FLAC3D).Based on the application of the small baseline subset-interferometric synthetic aperture radar(SBAS-InSAR)technique to SAR images from February 24,2017 to September 14,2022,a significant westward horizontal deformation was found to have been formed prior to the occurrence of the landslide.The maximum annual average deformation rate in the line of sight(LOS)direction reached-45 mm/yr,with a maximum cumulative deformation of-178 mm.This value was consistent with the continual increase in annual precipitation(2.51 mm/yr)prior to the occurrence of the landslide.The accumulated precipitation before the landslide was 279.8 mm,accounting for 54.2%of the total annual precipitation,with a particularly notable surge in monthly precipitation observed during August(250.3 mm).Additionally,the occurrence of a seismic event with a magnitude of Ms 6.9 in Menyuan County,80 km away from Xining,could be a potential triggering factor to the landslide,as evidenced by an abrupt subsidence alteration observed prior to and following the earthquake.The maximum subsidence in the line of sight(LOS)direction exceeded 11 mm,exhibiting a highly consistent spatial distribution with the occurrence range of landslides.These results suggest that the Jiujiawan landslide was likely induced by earthquake events in the early stage and heavy rainfall in the later stage.The FLAC3D numerical simulation show that after the landslide,the slope remained marginally stable under natural conditions;however,it is susceptible to reactivation with heavy rainfall.
基金supported by the Natural Science Foundation of Qinghai Province, China (No.2021-ZJ940Q)。
文摘In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway.
文摘为探讨电子束辐照对大豆品质的影响,以1.09、2.99、5.76、7.89、8.97 k Gy吸收剂量的电子束对大豆进行辐照处理,研究电子束辐照对大豆含油率、蛋白质含量、氨基酸的组成及含量、酸价、过氧化值、蛋白质溶解度及尿素酶活性的影响。结果表明,电子束辐照对大豆含油率、蛋白含量、氨基酸组成及含量影响较小;5.76 k Gy时,酸价降低了37.3%,8.97 k Gy时过氧化值及尿素酶活性分别降低37.5%和11.36%。综合分析可知,5.76 k Gy是大豆的电子束辐照储藏适宜剂量。本研究结果为电子束辐照在大豆储藏与加工中的应用提供了参考。
文摘以玉米和赭曲霉毒素A纯品为研究对象,研究了电子束辐照对玉米品质的影响,探讨了辐照对赭曲霉毒素A的降解效果。结果表明,电子束辐照对玉米的常规营养成分、氨基酸含量及其组成几乎没有影响,但5kGy剂量的电子束辐照对玉米脂肪酸组成及脂肪酸值有显著影响。赭曲霉毒素A的降解率随着辐照剂量的增加而提高,在3kGy的辐照剂量下,初始质量浓度为310.0μg/L的赭曲霉毒素A降解率为49.55%,当辐照剂量增大到5 k Gy时,降解率达到93.19%,此后降解率随辐照剂量增加的趋势变缓。因此,3~5 k Gy剂量的电子束辐照不会降低玉米品质,并能够降解赭曲霉毒素A。
