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青龙矿田兰旗组火山岩岩石学、地球化学特征及成因探讨
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作者 李国臣 孙祥 +1 位作者 罗毅 谷勇 《自然科学》 2015年第2期40-48,共9页
青龙铀矿田中侏罗统兰旗组为一套较厚中性火山熔岩–火山碎屑岩,是含矿层上覆最重要保护层。基于火山岩相学特征将兰旗组划分为3段:下段安山集块岩、安山角砾岩、及碎斑安山岩、安山岩;中段紫红色凝灰质砂岩、砾岩;上段气孔状安山岩夹... 青龙铀矿田中侏罗统兰旗组为一套较厚中性火山熔岩–火山碎屑岩,是含矿层上覆最重要保护层。基于火山岩相学特征将兰旗组划分为3段:下段安山集块岩、安山角砾岩、及碎斑安山岩、安山岩;中段紫红色凝灰质砂岩、砾岩;上段气孔状安山岩夹薄层黑云母晶屑凝灰岩。对各层位的火山熔岩进行了岩石地球化学分析,结果显示总体具有低镁低钛高铝高钾特征,属准铝质系列和高钾钙碱性系列;稀土元素、相容元素、不相容元素等显示下地壳岩浆混入幔源特征,并显示了各阶段混染程度存在强–弱–强演化趋势;岩浆成因并非大规模结晶分异,可能主要为部分熔融;其形成构造背景为板内造山环境,处于地壳缩短加厚晚期向减薄转换阶段。 展开更多
关键词 兰旗组 中性火山岩 岩石学 地球化学 成因
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Porous reduced graphene oxide for ultrasensitive detection of nitrogen dioxide
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作者 Zengyong Chu Min Xiao +4 位作者 Qichao Dong guochen li Tianjiao Hu Ye Zhang Zhenhua Jiang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第1期511-516,共6页
The defect engineering in graphene plays a significant role for the application of gas sensors. In this work, we proposed an efficient method to prepare ultrasensitive gas sensors based on the porous reduced graphene ... The defect engineering in graphene plays a significant role for the application of gas sensors. In this work, we proposed an efficient method to prepare ultrasensitive gas sensors based on the porous reduced graphene oxide(PRGO). Photo-Fenton etching was carried out on GO nanosheets in a controlled manner to enrich their vacancy defects. The resulting porous graphene oxide(PGO) was then drop-coated on interdigital electrodes and hydrothermal reduced at 180 °C. Controllable reduction was achieved by varying the water amount. The gas sensor based on PRGO-5 min-6h exhibited superior sensing and selective performance toward nitrogen dioxide(NO2), with an exceptional high sensitivity up to 12 ppm-1.The theoretical limit of detection is down to 0.66 ppb. The excellent performance could be mainly attributed to the typical vacancy defects of PRGO. Some residue carboxylic groups on the edges could also facilitate the adsorption of polar molecules. The process has a great potential for scalable fabrication of high-performance NO2gas sensors. 展开更多
关键词 Gas sensors Nitrogen dioxide Graphene oxide Photo-fenton reaction Porous reduced graphene oxide
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Role of depressive symptoms in cardiometabolic diseases and subsequent transitions to all-cause mortality:an application of multistate models in a prospective cohort study 被引量:3
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作者 Yanan Qiao Siyuan liu +4 位作者 guochen li Yanqiang Lu Ying Wu Yi Ding Chaofu Ke 《Stroke & Vascular Neurology》 SCIE CSCD 2021年第4期511-518,I0003,I0004,共10页
Background and purpose The role of depression in the development and outcome of cardiometabolic diseases remains to be clarified.We aimed to examine the extent to which depressive symptoms affect the transitions from ... Background and purpose The role of depression in the development and outcome of cardiometabolic diseases remains to be clarified.We aimed to examine the extent to which depressive symptoms affect the transitions from healthy to diabetes,stroke,heart disease and subsequent all-cause mortality in a middle-aged and elderly European population.Methods A total of 78212 individuals aged≥50 years from the Survey of Health Ageing and Retirement in Europe were included.Participants with any baseline cardiometabolic diseases including diabetes,stroke and heart disease were excluded.Depressive symptoms were measured by the Euro-Depression scale at baseline.Participants were followed up to determine the occurrence of cardiometabolic diseases and all-cause mortality.We used multistate models to estimate the transition-specific HRs and 95%CIs after adjustment of confounders.Results During 500711 person-years of follow-up,4742 participants developed diabetes,2173 had stroke,5487 developed heart disease and 7182 died.Depressive symptoms were significantly associated with transitions from healthy to diabetes(HR:1.12,95%CI:1.05 to 1.20),stroke(HR:1.31,95%CI:1.18 to 1.44),heart disease(HR:1.26,95%CI:1.18 to 1.34)and all-cause mortality(HR:1.41,95%CI:1.34 to 1.49).After cardiometabolic diseases,depressive symptoms were associated with the increased risk of all-cause mortality in patients with diabetes(HR:1.54,95%CI:1.25 to 1.89),patients who had stroke(HR:1.29,95%CI:1.03 to 1.61)and patients with heart disease(HR:1.21,95%CI:1.02 to 1.44).Conclusions Depressive symptoms increase the risk of diabetes,stroke and heart disease,and affect the risk of mortality after the onset of these cardiometabolic conditions.Screening and treatment of depressive symptoms may have profound implications for the prevention and prognosis of cardiometabolic diseases. 展开更多
关键词 DISEASES SYMPTOMS MORTALITY
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