The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these i...The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were studied.The above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater conditions.Comparatively,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and salinity.During the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant algae.Moreover,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial input.The OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and bacteria.Tectonic subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct differences.Overall,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace elements.The established models may have positive implications for research of lacustrine source rocks in offshore areas with few drillings.展开更多
目的系统评价葡萄糖酸氯己定抗菌敷料预防中心静脉导管相关性血流感染的疗效。方法通过PubMed、Web of Science、Embase、Cochrane Library、中国知网、中国生物医学文献数据库和万方等中英文数据库,检索关于葡萄糖酸氯己定抗菌敷料预...目的系统评价葡萄糖酸氯己定抗菌敷料预防中心静脉导管相关性血流感染的疗效。方法通过PubMed、Web of Science、Embase、Cochrane Library、中国知网、中国生物医学文献数据库和万方等中英文数据库,检索关于葡萄糖酸氯己定抗菌敷料预防导管相关静脉血流感染的中英文文献,检索时限均为建库至2021年8月10日。由2名研究人员独立按照设定的纳入与排除标准,纳入合格文献、提取文献信息和质量评价后,并采用RevMan 5.4软件进行Meta分析。结果最终共纳入12篇中英文文献,包括8773名患者。Meta分析结果显示,与普通敷料置于导管穿刺点相比,葡萄糖酸氯己定抗菌敷料能有效降低导管相关静脉血流感染的发生率(RR=0.47,95%CI:0.35~0.63),还能够降低患者导管细菌定植的发生率(RR=0.49,95%CI:0.32~0.57)。亚组分析发现,各亚组间差异均无统计学意义,表明氯己定抗菌敷料均能降低相关静脉血流感染的发生。结论葡萄糖酸氯己定抗菌敷料与普通敷料覆盖导管穿刺点相比,能够有效降低导管相关静脉血流感染的发生率和导管细菌定植发生率。展开更多
基金funded by the“Key Scientific Issues and Innovative Technology Research on Oil and Gas Resource Exploration in China Sea Risk Exploration Area”(Grant No.CCL2022RCPS2017XNN)from CNOOC Research Institute,Beijing.
文摘The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were studied.The above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater conditions.Comparatively,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and salinity.During the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant algae.Moreover,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial input.The OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and bacteria.Tectonic subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct differences.Overall,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace elements.The established models may have positive implications for research of lacustrine source rocks in offshore areas with few drillings.
文摘目的系统评价葡萄糖酸氯己定抗菌敷料预防中心静脉导管相关性血流感染的疗效。方法通过PubMed、Web of Science、Embase、Cochrane Library、中国知网、中国生物医学文献数据库和万方等中英文数据库,检索关于葡萄糖酸氯己定抗菌敷料预防导管相关静脉血流感染的中英文文献,检索时限均为建库至2021年8月10日。由2名研究人员独立按照设定的纳入与排除标准,纳入合格文献、提取文献信息和质量评价后,并采用RevMan 5.4软件进行Meta分析。结果最终共纳入12篇中英文文献,包括8773名患者。Meta分析结果显示,与普通敷料置于导管穿刺点相比,葡萄糖酸氯己定抗菌敷料能有效降低导管相关静脉血流感染的发生率(RR=0.47,95%CI:0.35~0.63),还能够降低患者导管细菌定植的发生率(RR=0.49,95%CI:0.32~0.57)。亚组分析发现,各亚组间差异均无统计学意义,表明氯己定抗菌敷料均能降低相关静脉血流感染的发生。结论葡萄糖酸氯己定抗菌敷料与普通敷料覆盖导管穿刺点相比,能够有效降低导管相关静脉血流感染的发生率和导管细菌定植发生率。
