In order to solve water resources problems in the North China Plain, this paper explored human-nature compound water circulation system from three aspects including urban flood control, surface drainage and saline wat...In order to solve water resources problems in the North China Plain, this paper explored human-nature compound water circulation system from three aspects including urban flood control, surface drainage and saline water in the central and eastern of the North China Plain. Results show that:(1) The technical methods have achieved zero increase in rainwater runoff in urban areas,(2) surface drainage depletion problems can be solved through abandoned water and river water separation method,(3) and technical method through promoting rainwater infiltration would be used to solve problem of saline water in the central and eastern parts. This research provides a new perspective to the ultimate solutions to water resources problems in the North China Plain, and a fresh research direction for the development of hydro-geological science.展开更多
In the typical region of central North China Plain, vadose sediments are Holocene sediment strata. With samples from field drillings, the study analyzes the sedimentary characteristics of vadose zone. The study takes ...In the typical region of central North China Plain, vadose sediments are Holocene sediment strata. With samples from field drillings, the study analyzes the sedimentary characteristics of vadose zone. The study takes the content of silty sand as the basis for sedimentary environment analysis, and the content of clay and sand as the sensitive indicator for sedimentary characteristics. Combining palynology analysis, the study divides vadose zone from top to bottom into diluvia oxbow lacustrine sediments, lacustrine sediments, lacustrine and swamp sediments, weak palaeohydrodynamic lacustrine sediments and alluvial sediments. Based on the sedimentary characteristics of Holocene strata, it analyzes the changes across depth of vadose zone water potential and matrix potential, obtaining the influence of vadose zone sedimentary characteristics on the migration of water in typical region of central North China Plain.展开更多
Although the Chinese people have, through continuous efforts, built the constantly improving Yellow River flood control system, and created a miracle which has been tranquil for over 50 years, the tendency for the dow...Although the Chinese people have, through continuous efforts, built the constantly improving Yellow River flood control system, and created a miracle which has been tranquil for over 50 years, the tendency for the downstream watercourse of the Yellow River to uplift every year has not been fundamentally curbed, and the aboveground river is still the “scourge” of the sons and daughters of the Yellow River. By the use of a variety of modern investigation and survey methods, the geological environment characteristics of the downstream of the Yellow River have been identified basically, including the environmental and geological factors affecting the stability of aboveground rivercourse of the lower Yellow River such as the active fracture of the lower Yellow River, crustal uplift, land subsidence, seismic activity, geological conditions of dike foundation engineering, hydrodynamic conditions of rivers, and geomorphology of watercourses. After a comprehensive analysis of the inability mode of aboveground river on the downstream of the Yellow River and its corresponding impact factors, by using the fuzzy comprehensive evaluation method, we have evaluated the crustal stability of the aboveground river, dike foundation stability, watercourse landform stability and overall stability. The results of comprehensive results show that the stability of downstream aboveground rivercourse of the Yellow River can be divided into four grades and 11 sections, i e. “basically stable, unstable, very unstable and extremely unstable”. On the basis of the stability segmentation, we consider the influence of integrally the future structural faults, earthquakes, the difference of watercourse between forward and backward heights of dikes, river regime and river type, historical crevasses, foundation soil liquefaction and seepage deformation, and find out 17 most unstable danger points. Finally, from 17 danger points, we select 7 danger points which are most prone to instability including Wuzhi, Zhongmou, Kaifeng, Fengqiu, Dongming, Changyuan and Dong’e. The calculation and analysis of the range and area inundated by 7 danger points, area, and number of people threatened, possible economic loss, and environmental damage, the inability caused by any one of 7 points could bring disastrous consequences to the downstream.展开更多
文摘目的:通过前瞻性观察性研究分析非瓣膜性房颤脑梗死无症状性出血转化患者的临床资料,探讨合并房颤的急性脑梗死出血转化患者行低剂量低分子肝素(low-molecular-weight heparin,LMWH)抗凝治疗的疗效。方法:纳入2016年1月至2018年11月在如皋市人民医院神经内科住院的非瓣膜性房颤脑梗死无症状性出血转化患者120例,根据是否予以低剂量低分子肝素抗凝治疗,分为抗凝组(n=56)和对照组(n=64),分析入组患者急性期的临床资料,随访30 d,以美国国立卫生研究院卒中量表(the National Institutes of Health Stroke Scale,NIHSS)减分值、30 d改良Rankin(mRs)评分、30 d良好预后(mRs 2分)、再发脑梗死、其他栓塞事件、颅内外出血事件为主要观察指标。结果:抗凝组和对照组在NIHSS减分值、再发脑梗死(1.79%vs 14.06%)差异有统计学意义(P<0.05);30 d mRs评分、30 d良好预后、颅内外出血事件及其他栓塞事件差异无统计学意义;单因素(抗凝治疗)分析显示,NIHSS减分值(OR=2.41,95%CI 1.30~3.51)、再发脑梗死(OR=0.10,95%CI 0.01~0.79)差异有统计学意义(P<0.05);多因素分析显示,NIHSS减分值(OR=39.87,95%CI 21.98~57.77)、再发脑梗死(OR=0.10,95%CI 0.01~0.86)差异有统计学意义(P<0.05)。结论:合并非瓣膜性房颤的急性脑梗死无症状性出血转化患者行低剂量低分子肝素抗凝治疗能改善神经功能,降低再发脑梗死风险,且不增加颅内外出血事件。
基金funded by National Key Basic Research Program of China(2010CB428800),Geological Survey(20023064)(12120113102400)
文摘In order to solve water resources problems in the North China Plain, this paper explored human-nature compound water circulation system from three aspects including urban flood control, surface drainage and saline water in the central and eastern of the North China Plain. Results show that:(1) The technical methods have achieved zero increase in rainwater runoff in urban areas,(2) surface drainage depletion problems can be solved through abandoned water and river water separation method,(3) and technical method through promoting rainwater infiltration would be used to solve problem of saline water in the central and eastern parts. This research provides a new perspective to the ultimate solutions to water resources problems in the North China Plain, and a fresh research direction for the development of hydro-geological science.
基金support from Groundwater Scientific and Engineering Key Laboratory Open Fund of the Ministry of Land and Resources and the National Survey and Evaluation Project on Groundwater Resources and Environmental Issues (1212011121147)
文摘In the typical region of central North China Plain, vadose sediments are Holocene sediment strata. With samples from field drillings, the study analyzes the sedimentary characteristics of vadose zone. The study takes the content of silty sand as the basis for sedimentary environment analysis, and the content of clay and sand as the sensitive indicator for sedimentary characteristics. Combining palynology analysis, the study divides vadose zone from top to bottom into diluvia oxbow lacustrine sediments, lacustrine sediments, lacustrine and swamp sediments, weak palaeohydrodynamic lacustrine sediments and alluvial sediments. Based on the sedimentary characteristics of Holocene strata, it analyzes the changes across depth of vadose zone water potential and matrix potential, obtaining the influence of vadose zone sedimentary characteristics on the migration of water in typical region of central North China Plain.
文摘Although the Chinese people have, through continuous efforts, built the constantly improving Yellow River flood control system, and created a miracle which has been tranquil for over 50 years, the tendency for the downstream watercourse of the Yellow River to uplift every year has not been fundamentally curbed, and the aboveground river is still the “scourge” of the sons and daughters of the Yellow River. By the use of a variety of modern investigation and survey methods, the geological environment characteristics of the downstream of the Yellow River have been identified basically, including the environmental and geological factors affecting the stability of aboveground rivercourse of the lower Yellow River such as the active fracture of the lower Yellow River, crustal uplift, land subsidence, seismic activity, geological conditions of dike foundation engineering, hydrodynamic conditions of rivers, and geomorphology of watercourses. After a comprehensive analysis of the inability mode of aboveground river on the downstream of the Yellow River and its corresponding impact factors, by using the fuzzy comprehensive evaluation method, we have evaluated the crustal stability of the aboveground river, dike foundation stability, watercourse landform stability and overall stability. The results of comprehensive results show that the stability of downstream aboveground rivercourse of the Yellow River can be divided into four grades and 11 sections, i e. “basically stable, unstable, very unstable and extremely unstable”. On the basis of the stability segmentation, we consider the influence of integrally the future structural faults, earthquakes, the difference of watercourse between forward and backward heights of dikes, river regime and river type, historical crevasses, foundation soil liquefaction and seepage deformation, and find out 17 most unstable danger points. Finally, from 17 danger points, we select 7 danger points which are most prone to instability including Wuzhi, Zhongmou, Kaifeng, Fengqiu, Dongming, Changyuan and Dong’e. The calculation and analysis of the range and area inundated by 7 danger points, area, and number of people threatened, possible economic loss, and environmental damage, the inability caused by any one of 7 points could bring disastrous consequences to the downstream.
