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The reservoir lithology of the fourth Member of Dengying Formation in the north-central Sichuan Basin is complex with strong heterogeneity， which limits the gas reservoir exploration in the fourth Member of Dengying Formation. To further deepen the understanding of sedimentary facies and reservoir characteristics in Well DB1 area in north-central Sichuan， the sedimentary facies and reservoir characteristics of the fourth Member of Dengying Formation in Well DB1l area in the north-central Sichuan were studied based on the data of drilling core， thin section observation， well logging， log， physical property test， and drilling results. The results show that two sedimentary subfacies of platform margin and restricted platform are mainly developed in the fourth Member of Dengying Formation in the study area， and sedimentary microfacies such as algal mound， grain beach， and inter-beach sea were further identified. Among them， algal mound microfacies mainly develop algal clot dolomite and algal stromatolite dolomite， grain beach microfacies mainly develop calcarenite dolomite， and inter-beach sea microfacies mainly develop micritic dolomite and powder crystal dolomite. The algal mounds and grain beaches in the fourth Member of Dengying Formation in the study area are mainly developed on the side of the platform margin， and the deposition of algal mounds and grain beaches in the platform gradually decreases mainly inter-beach sea deposition. The development of algal mounds in the fourth Member of the Dengying Formation in the study area is characterized by longitudinal superposition， and the horizontal extension is relatively close. Meanwhile， the algal mounds are concentrated in the Upper Submember of the fourth Member of Dengying Formation with large monomer thickness， while the Lower Submember of the fourth Member of Dengying Formation is less developed and thinner. The reservoir rock types of the fourth Member of Dengying Formation in the study area are mainly algal clot dolomite， algal stromatolite dolomite， and calcarenite dolomite. The reservoir space is mainly algal binding framework pore， intergranular dissolved pore， and intergranular dissolved pore. The core porosity of the fourth Member of Dengying Formation in the study area is distributed between 2.02% and 6.03% with an overall average porosity of 3.11%， the core permeability is distributed between 0.007 04 and 9.78 mD， and the overall average permeability is 0.692 64 mD. The overall physical properties are characterized by low porosity and ultra-low permeability， and some samples show low porosity and high permeability due to the influence of fractures.

Objective: To investigate the prevalence, awareness, treatment, control and related influence factors of hypertension among rural adult residents in areas along the Yangtze River in Anhui Province., Methods: Totally 2873 rural adult residents in seven typical towns along the Yangtze River of Chizhou, Tongling and Ma'anshan Cities, Anhui Province were selected, with multistage-stratified random cluster sampling, to perform questionnaires and physical measurements from year 2014 to 2015., Results: The prevalence of hypertension was 30. 7%( standardized prevalence was 18. 4%), the awareness rate was 50. 6%( standardized rate was 29. 0%), the treatment rate was40. 4%( standardized rate was 18. 7%), the control rate was 17. 7%( standardized ratewas 9. 3%) in rural areas along the Yangtze River in Anhui Province. The prevalence, awareness, treatment and control rates of hypertension were increased with age increase. Abdominal obesity( OR = 1. 855, 95% CI 1. 467-2. 344), family history of hypertension( OR = 1. 594, 95% CI 1. 265-2. 008), the average annual household income < 60 000 yuan and increased BMI were risk factors of hypertension in rural areas along the Yangtze River. Female( OR = 0. 734, 95% CI 0. 604-0. 891) was its protective factors. While the factors of awareness, treatment and control rates of hypertension were not same., Conclusion: The prevalence of hypertension is higher in the areas along the Yangtze River in Anhui Province. However, the awareness, treatment and control rate of hypertension are lower.