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| 1 | Drainage evolution in intermontane basins at the Qinling-Daba Mountains显示文摘River capture is of great significance to landform evolution and hominine migration.In the Qinling-Daba Mountains,there is a viewpoint that Jialing River captured Hanjiang River,but this is still controversial.In this paper,we discuss the drainage evolution processes in intermountain basins at the Qinling-Daba Mountains based on a combination of detrital zircon UPb geochronology and geomorphic indexes.We suggest that the Hanjiang River gradually captured the Jialing River from east to west,accompanied by the evolution of the ancient Yangtze River.In terms of geomorphic evidences,wide valleys did not match with discharge,and a series of wind gaps developed in the Shiquan-Ankang basin.In addition,the valley shapes and width-toheight ratios(Vf)indicate two possible rapid incisions.The hypsometric integrals(HI)reflect that the landform gradually changes from the old stage to the youth stage from west to east.Theχvalues show that the drainage divide is moving to the side of the Yuehe River,and the Yuehe River is gradually shrinking.According to the sedimentary records,the zircon U-Pb age distributions indicate the provenance change.The high-altitude terraces show three age peaks(200–250,400–505,and 700–900 Ma),with the dominant Indosinian age peak(200–250 Ma),while the modern fluvial sediments only show a single peak of Jinning(700–900 Ma).These data show that there are two major river captures:(1)The ancient Hanjiang River cut through the regional compression ridge,and then captured the Hanzhong Basin river system(a part of the ancient Jialing river system)from east to west,and(2)The southern tributary captured the trunk with the uplift of the divide in the Shiquan-Ankang Basin,forming the modern drainage pattern in the upper Hanjiang River.The activities of the regional strike-slip fault,and the associated compression uplift played a key role in the river captures,the drainage evolution,and related landforms in the Shiquan-Ankang basin.In addition,it is shown that the evolution of the upper tributary basins lagged behind the response of the trunk channel to the tectonic activities and river captures.The interconnected wide valleys caused by river capture may have provided convenient geomorphological conditions for human migration into the Qinling-Daba Mountains along those river valleys. | Wanting XIE Xianyan WANG Hanzhi ZHANG Quanyu LIU Shejiang WANG Huayu LU | 2021 | Science China Earth Sciences2021，64，11： | 1 |
| 2 | miRNA -regulated expression of oncogenes and tumor suppressor genes in the cisplatin -inhibited growth of K562 cells显示文摘 | Xie SY Li Y J Want PY | 2010 | Oncol Rep2010，23，6： | 1 |
| 3 | In-Orbit Calibration Uncertainty of the Microwave Radiation Imager on board Fengyun-3C显示文摘This study evaluates the in-orbit calibration uncertainty(CU)for the microwave radiation imager(MWRI)on board the Chinese polar-orbiting meteorological satellite Fengyun-3 C(FY-3 C).Uncertainty analysis of the MWRI provides a direct link to the calibration system of the sensor and quantifies the calibration confidence based on the prelaunch and postlaunch measurements.The unique design of the sensor makes the uncertainty in the calibration of the sensor highly correlate to the uncertainty in the brightness temperature(TB)measured at the hot view,while the cold view has negligible impacts on the calibration confidence.Lack of knowledge on the emission of the hot-load reflector hampers the MWRI calibration accuracy significantly in the descending passes of the orbits when the hotload reflector is heated nonuniformly by the solar illumination.Radiance contamination originating from the satellite and in-orbit environments could enter the primary reflector via the hot view and further impinge on the CU,especially at the 10.65-GHz channels where the main-beam width is much broader than that of higher-frequency channels.The monthly-mean CU is lower than 2 K at all channels,depending on the observed earth scenes and in-orbit environments,and the month-to-month variation of CU is also noticed for all channels.Due to the uncertainty in the emissive hot-load reflector,CU in the descending passes is generally larger than that in the ascending orbits.Moreover,up to 1-K CU difference between the ocean and land scenes is found for the 10.65-GHz channels,while this difference is less than 0.1 K at the 89-GHz channels. | Xinxin XIE Wanting MENG Jiakai HE Weimin YU Xue LI | 2021 | Journal of Meteorological Research2021，35，6： | 0 |
| 4 | Risk Assessment and Change Monitoring of Soil and Water Loss in Ruijin City Based on RS and GIS显示文摘The land use information extraction technology for the high-resolution remote sensing images of the Gaofen No. 1 satellite was constructed. According to the spectral,band,texture and shape attributes,land use types were divided,and the changing laws of land use types were analyzed. Afterwards,according to the Table of Grading Standard of Soil Erosion Intensity( SL190-96),as well as vegetation coverage index NDVI and slope,the risks of soil and water loss were assessed. Meanwhile,the level,scale,location and scope of changes in the risks of soil and water loss were monitored by using spatial visualization and spatial statistical techniques. The results showed that the area of areas without soil erosion and moderate soil erosion areas decreased obviously from 2015 to 2017,and the decreases were up to 22. 929 3 and 13. 626 3 km^2 respectively. The area of mild soil erosion areas increased fast,and the increase reached 31. 140 0 km^2. The area of extremely strong soil erosion areas increased by7. 267 4 km^2. In the city,moderate and strong soil erosion areas reduced,while extremely strong soil erosion patches increased fast,which was mainly related to road construction and construction and development of orchards. The extremely strong soil erosion areas were distributed in the shape of a banded loop,surrounded the suburbs of the city,and shrank towards the center of Ruijin City. The constructed technology to monitor the changes in land use and soil and water loss,as well as the changing laws of land use and soil and water loss provide the theoretical basis and planning basis of soil and water conservation for urban planning departments and soil and water conservation departments. | Zhou Peng Wang Li Xie Wanting Lu Jiangyue Zhang Xiaoxu Xu Wei | 2018 | Meteorological and Environmental Research2018，9，4： | 0 |
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