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证候空间和方剂空间的数学结构 被引量:2
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作者 杨凤翔 王顺庆 《生物数学学报》 CSCD 北大核心 1990年第2期115-121,共7页
本文考察了中医理、法、方、药原理,给出了证候空间和方剂空间的数学结构,以利于中医现代化和中医临床中应用电子计算机诊疗技术。
关键词 证候空间 方剂空间 数学结构
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Organochlorine pesticides in soils from the Issyk-Kul region in the western Tian Shan Mountains,Kyrgyzstan:Implication for spatial distribution,source apportionment and ecological risk assessment
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作者 LI Qian-yu WU Jing-lu +1 位作者 ZHAO Zhong-hua SAKIEV Kadyrbek 《Journal of Mountain Science》 SCIE CSCD 2018年第7期1520-1531,共12页
As organchlorine pesticides(OCPs) may be an ecologic threat to mountain environments due to their tendency to deposit and accumulate in mountain regions undergoing long-range air transport, OCPs were analyzed in soils... As organchlorine pesticides(OCPs) may be an ecologic threat to mountain environments due to their tendency to deposit and accumulate in mountain regions undergoing long-range air transport, OCPs were analyzed in soils collected from an intermontane basin of the western Tian Shan Mountains, which is the UNESCO protected natural reserve of Issyk-Kul. Total OCP concentrations in the Issyk-Kul region ranged from 4.63 to 414 ng/g dw, of which two extraordinary high OCP concentrations(414 ng/g dw and 213 ng/g dw, respectively) influenced by an abandoned dumping site and urban sewage, respectively, were found. Principal component analysis(PCA) and correlation analysis inferred that the OCP inputs in the east of the Issyk-Kul region were mainly from local endogenous sources, and exogenous input via LRAT processes were prominent in the west and south. Additionally, the isomeric and parent substance/metabolite ratios revealed most pesticides accumulated in this region were from old usage, while DDTs had fresh input because of possibly illegal regional application and a slow degradation from the dumping site. Furthermore, ecological risk assessment revealed that no frequently adverse ecological effects were observed in the Issyk-Kul region, but potential risks on neighbouring organisms induced by p,p'-DDT and γ-HCH in dumping site and urban sewage should be considered when devising an efficient management plan to prevent secondary pollution. 展开更多
关键词 Organchlorine pesticides Pesticide distribution Pesticide sources Ecological risks Issyk-Kul region Tian Shan Mountains
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