Alkaline lacustrine shale is highly heterogeneous,and the complex relationship between the organicinorganic porosity network and hydrocarbon occurrence restricts the effectiveness of shale oil exploration and developm...Alkaline lacustrine shale is highly heterogeneous,and the complex relationship between the organicinorganic porosity network and hydrocarbon occurrence restricts the effectiveness of shale oil exploration and development.Herein,we investigated the Fengcheng Formation(P_(1)f)in Mahu Sag.This study integrated geochemistry,Soxhlet extraction,scanning electron microscopy,gas adsorption,and nuclear magnetic resonance T_(1)-T_(2)spectroscopy to elucidate the microscopic oil occurrence mechanisms in shales.Results indicate the presence of felsic shale,dolomitic shale,lime shale,and mixed shale within the P_(1)f.Matrix pores and microfractures associated with inorganic minerals are the predominant pore types in P_(1)f.Adsorbed oil primarily resides on the surfaces of organic matter and clay minerals,while free oil predominantly occupies inorganic pores and microfractures with larger pore sizes.Variations exist in the quantity and distribution of shale oil accumulation across different scales,where free oil and adsorbed oil are governed by dominant pores with diameters exceeding 10 nm and ineffective pores with diameters below 10 nm,respectively.Shale oil occurrence characteristics are influenced by organic matter,pore structure,and mineral composition.Felsic shale exhibits a high abundance of dominant pores,possesses the highest oil content,predominantly harbors free oil within these dominant pores,and demonstrates good mobility.Fluid occurrence in dolomitic shale and lime shale is intricate,with low oil content and a free oil to adsorbed oil ratio of 1:1.Mixed shale exhibits elevated clay mineral content and a scarcity of dominant pores.Moreover,ineffective pores contain increased bound water,resulting in medium oil content and limited mobility predominantly due to adsorption.Presently,shale oil mainly occurs in the dominant pores with a diameter larger than 10 nm in a free state.During the exploration and development of alkaline lacustrine shale oil resources,emphasis should be placed on identifying sweet spots within the felsic shale characterized by dominant pores.展开更多
To investigate oral health status in the residents of Sichuan Province, southwest China, a cross-sectional study was performed using the latest Oral Health Survey Basic Methods recommended by the World Health Organiza...To investigate oral health status in the residents of Sichuan Province, southwest China, a cross-sectional study was performed using the latest Oral Health Survey Basic Methods recommended by the World Health Organization. A multistage stratified random cluster-sampling method was used to enroll participants from the following three groups： children aged 3-5 years, adolescents aged 12 years, and people aged 65-74 years. In these three groups, the mean numbers of teeth that were affected by caries were 3.28, 0.86 and 5.13, respectively, resulting in a prevalence of 63.47%, 37.20% and 83.20%, respectively. Relative to the high rate of decayed teeth, the prevalence of fillings was very low in all age groups （0.97%, 7.24% and 5.43%, respectively）, In the 12-year-old adolescent group, only 3.61% had good pit and fissure sealing. In addition, the rate of dental fluorosis was 24.80%, and the Community Fluorosis Index value was 0.39. In the elder group, the community periodontal index was 2.92. The prevalence in the elderly of having lost at least one tooth was 75.54%. Additionally, 4.44% of these participants were edentulous. The incidence of dental prosthesis was 51.75%, the proportion with a removable partial denture, a fixed denture, full dentures, dental implants and an informal fixed bridge was 21.59%, 11.45%, 4.64%, 0 and 16.67%, respectively. In this study, 8.2% of the elderly participants were affected by different types of oral mucosal lesions. Among such lesions, recurrent aphthous ulcers were most prevalent （2.69%） and oral lichen planuses were second （1.6%）. The conclusion presented in this survey is that oral diseases, especially dental caries and periodontal disease, are frequent and common in Sichuan province, China. Moreover, the treatment rate is very low, and primary prevention and treatment options are therefore urgently needed in this population.展开更多
Objective: To understand the health status of transitional resettlement sites and the needs of residents on health education, and to pro-vide basis for conducting health education after ear- thquakes and other public ...Objective: To understand the health status of transitional resettlement sites and the needs of residents on health education, and to pro-vide basis for conducting health education after ear- thquakes and other public emergen-cies. Method: From May 31 to June 2, 2008 (19 to 21 days after the earthquake), field obser-vation, questionnaire survey, and structured interviews were conducted in five transitional resettlement sites. Information on health status, health service, health education, and residents’ needs on health education was col-lected. Results: 430 questionnaires were dis-tributed and 424 valid completed ones were returned. Food and water were adequately supplied. Clinics for health assistance were established and environment disinfecting was conducted regularly by public health profes-sionals. Health education was available to residents. The large proportion (98.6%, 97.9%, 88.7%, and 93.2% respectively) of the residents acknowledged that water supply, food supply, lavatories, and health service were adequate to fulfill basic needs. The overall disease in-cidence of surveyed residents was 44.8%, and diarrhea and fever with respiratory symptoms were the most common diseases. Among residents’ needs on disease prevention knowl-edge and skills, basic knowledge of infectious diseases was most desirable (49.8%), and safety knowledge of water uses was secon-darily most desirable (36.8%). The most fa-vored approach of obtaining knowledge was watching television. Conclusions: In the pe-riod of 20 days after the earthquake, Living security, health facilities, and health care ser-vice could satisfy residents’ basic needs. Post-disaster health education should con-centrate on basic knowledge and skills of communicable diseases and health- risky be-havior. Timely distributing disease prevention materials could be effective.展开更多
空间碎片高精度定轨、碰撞预警和清除等技术问题对高精度空间碎片测量数据提出了迫切需求。激光测距技术是目前精度最高的空间碎片观测手段,然而大部分空间碎片轨道预报精度差,降低了空间碎片测距的成功率。文中提出了一种基于时间偏差...空间碎片高精度定轨、碰撞预警和清除等技术问题对高精度空间碎片测量数据提出了迫切需求。激光测距技术是目前精度最高的空间碎片观测手段,然而大部分空间碎片轨道预报精度差,降低了空间碎片测距的成功率。文中提出了一种基于时间偏差修正的空间碎片轨道预报优化方法,旨在提高测距过程中对碎片的稳定跟踪能力,进而获得更多的观测数据。通过选取Starlette、Larets和Lares三颗精密定轨卫星,基于两行根数(Two Line Element,TLE)轨道时间偏差修正与SP3精密星历的对比验证了方法的有效性,三颗卫星的视位置偏差较初始值分别减少51.7%、76.0%和95.0%。进而提出把预报方位角俯仰角时间序列看作整体的时间偏差计算方法,实现了三颗卫星时间偏差的仿真计算。实验依托中国科学院云南天文台1.2 m望远镜实际跟踪TLE预报的大量空间碎片,从实验上分析文中提出方法的有效性。空间碎片观测实验结果为,方位角偏差的平均修正量为83.5%,俯仰角偏差的平均修正量为79.8%,时间偏差修正方法可大幅修正碎片预报位置偏差,该方法可为不可见空间碎片的跟踪提供技术支撑,提升激光测距系统全天时观测能力。展开更多
基金financially supported by the State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development(33550000-22-ZC0613-0006)National Natural Science Foundation of China(42202133)+2 种基金CNPC Innovation Fund(2022DQ02-0106)Strategic Cooperation Technology Projects of the CNPC and CUPB(ZLZX2020-01-05)Key Laboratory of Tectonics and Petroleum Resources(China University of Geosciences),Ministry of Education,China(TPR-2023-05)。
文摘Alkaline lacustrine shale is highly heterogeneous,and the complex relationship between the organicinorganic porosity network and hydrocarbon occurrence restricts the effectiveness of shale oil exploration and development.Herein,we investigated the Fengcheng Formation(P_(1)f)in Mahu Sag.This study integrated geochemistry,Soxhlet extraction,scanning electron microscopy,gas adsorption,and nuclear magnetic resonance T_(1)-T_(2)spectroscopy to elucidate the microscopic oil occurrence mechanisms in shales.Results indicate the presence of felsic shale,dolomitic shale,lime shale,and mixed shale within the P_(1)f.Matrix pores and microfractures associated with inorganic minerals are the predominant pore types in P_(1)f.Adsorbed oil primarily resides on the surfaces of organic matter and clay minerals,while free oil predominantly occupies inorganic pores and microfractures with larger pore sizes.Variations exist in the quantity and distribution of shale oil accumulation across different scales,where free oil and adsorbed oil are governed by dominant pores with diameters exceeding 10 nm and ineffective pores with diameters below 10 nm,respectively.Shale oil occurrence characteristics are influenced by organic matter,pore structure,and mineral composition.Felsic shale exhibits a high abundance of dominant pores,possesses the highest oil content,predominantly harbors free oil within these dominant pores,and demonstrates good mobility.Fluid occurrence in dolomitic shale and lime shale is intricate,with low oil content and a free oil to adsorbed oil ratio of 1:1.Mixed shale exhibits elevated clay mineral content and a scarcity of dominant pores.Moreover,ineffective pores contain increased bound water,resulting in medium oil content and limited mobility predominantly due to adsorption.Presently,shale oil mainly occurs in the dominant pores with a diameter larger than 10 nm in a free state.During the exploration and development of alkaline lacustrine shale oil resources,emphasis should be placed on identifying sweet spots within the felsic shale characterized by dominant pores.
基金funded by a grant from Scientific Research in the Public Interest(201502002)conducted by the Department of Preventive Dentistry,West China Hospital of Stomatology,Sichuan University,China
文摘To investigate oral health status in the residents of Sichuan Province, southwest China, a cross-sectional study was performed using the latest Oral Health Survey Basic Methods recommended by the World Health Organization. A multistage stratified random cluster-sampling method was used to enroll participants from the following three groups： children aged 3-5 years, adolescents aged 12 years, and people aged 65-74 years. In these three groups, the mean numbers of teeth that were affected by caries were 3.28, 0.86 and 5.13, respectively, resulting in a prevalence of 63.47%, 37.20% and 83.20%, respectively. Relative to the high rate of decayed teeth, the prevalence of fillings was very low in all age groups （0.97%, 7.24% and 5.43%, respectively）, In the 12-year-old adolescent group, only 3.61% had good pit and fissure sealing. In addition, the rate of dental fluorosis was 24.80%, and the Community Fluorosis Index value was 0.39. In the elder group, the community periodontal index was 2.92. The prevalence in the elderly of having lost at least one tooth was 75.54%. Additionally, 4.44% of these participants were edentulous. The incidence of dental prosthesis was 51.75%, the proportion with a removable partial denture, a fixed denture, full dentures, dental implants and an informal fixed bridge was 21.59%, 11.45%, 4.64%, 0 and 16.67%, respectively. In this study, 8.2% of the elderly participants were affected by different types of oral mucosal lesions. Among such lesions, recurrent aphthous ulcers were most prevalent （2.69%） and oral lichen planuses were second （1.6%）. The conclusion presented in this survey is that oral diseases, especially dental caries and periodontal disease, are frequent and common in Sichuan province, China. Moreover, the treatment rate is very low, and primary prevention and treatment options are therefore urgently needed in this population.
文摘Objective: To understand the health status of transitional resettlement sites and the needs of residents on health education, and to pro-vide basis for conducting health education after ear- thquakes and other public emergen-cies. Method: From May 31 to June 2, 2008 (19 to 21 days after the earthquake), field obser-vation, questionnaire survey, and structured interviews were conducted in five transitional resettlement sites. Information on health status, health service, health education, and residents’ needs on health education was col-lected. Results: 430 questionnaires were dis-tributed and 424 valid completed ones were returned. Food and water were adequately supplied. Clinics for health assistance were established and environment disinfecting was conducted regularly by public health profes-sionals. Health education was available to residents. The large proportion (98.6%, 97.9%, 88.7%, and 93.2% respectively) of the residents acknowledged that water supply, food supply, lavatories, and health service were adequate to fulfill basic needs. The overall disease in-cidence of surveyed residents was 44.8%, and diarrhea and fever with respiratory symptoms were the most common diseases. Among residents’ needs on disease prevention knowl-edge and skills, basic knowledge of infectious diseases was most desirable (49.8%), and safety knowledge of water uses was secon-darily most desirable (36.8%). The most fa-vored approach of obtaining knowledge was watching television. Conclusions: In the pe-riod of 20 days after the earthquake, Living security, health facilities, and health care ser-vice could satisfy residents’ basic needs. Post-disaster health education should con-centrate on basic knowledge and skills of communicable diseases and health- risky be-havior. Timely distributing disease prevention materials could be effective.
文摘空间碎片高精度定轨、碰撞预警和清除等技术问题对高精度空间碎片测量数据提出了迫切需求。激光测距技术是目前精度最高的空间碎片观测手段,然而大部分空间碎片轨道预报精度差,降低了空间碎片测距的成功率。文中提出了一种基于时间偏差修正的空间碎片轨道预报优化方法,旨在提高测距过程中对碎片的稳定跟踪能力,进而获得更多的观测数据。通过选取Starlette、Larets和Lares三颗精密定轨卫星,基于两行根数(Two Line Element,TLE)轨道时间偏差修正与SP3精密星历的对比验证了方法的有效性,三颗卫星的视位置偏差较初始值分别减少51.7%、76.0%和95.0%。进而提出把预报方位角俯仰角时间序列看作整体的时间偏差计算方法,实现了三颗卫星时间偏差的仿真计算。实验依托中国科学院云南天文台1.2 m望远镜实际跟踪TLE预报的大量空间碎片,从实验上分析文中提出方法的有效性。空间碎片观测实验结果为,方位角偏差的平均修正量为83.5%,俯仰角偏差的平均修正量为79.8%,时间偏差修正方法可大幅修正碎片预报位置偏差,该方法可为不可见空间碎片的跟踪提供技术支撑,提升激光测距系统全天时观测能力。
