Research on effective source rocks directly affects the accuracy of identifying hydrocarbon resources, and indirectly affects the exploration decisions in petroliferous basins. Although the previous evaluation methods...Research on effective source rocks directly affects the accuracy of identifying hydrocarbon resources, and indirectly affects the exploration decisions in petroliferous basins. Although the previous evaluation methods of effective source rocks vary relatively widely, a complete quantitative evaluation approach has not yet been developed. For that reason, we redefined the concept of effective source rocks based on the existing research results. Surrounding this definition, and guided by the hydrocarbon expulsion theory, the quantitative model called ＂two stages and three steps＂ method is established to predict effective source rocks. Its application in the Bozhong Depression indicates that among the four sets source rocks in the Bozhong Depression, the Member 3 of the Shahejie Formation （Es 3 ） has the largest effective source rock thickness, and the Member 1 Member 2 of the Shahejie Formation （Es 1＋2 ） is the second largest .The effective part of dark mudstone is only 30%-80% of the total volume and with the increase of buried depth and improvement of quality, the effective part increases. Comprehensive analysis indicates that the ＂two stages and three steps＂ method is a practical technique for effective source rock prediction.展开更多
In the context of the COVID-19 pandemic and under the pressure of high competitiveness for higher education in China,junior high school students’mental health is facing greater challenges.Understanding the time alloc...In the context of the COVID-19 pandemic and under the pressure of high competitiveness for higher education in China,junior high school students’mental health is facing greater challenges.Understanding the time allocation of study and sleep is necessary for developing effective prevention and treatment programs.Based on a survey of 31,057 junior high school students in 47 junior high schools in Gansu Province,China's Mainland,the study analyzed the associations of time spent on study and sleep with anxiety and depressive symptoms among junior high school students through chi-square test,ANOVA,logistic regression model and threshold regression model.It was found that 18.4%–21.1%of junior high school students had mild and above anxiety and depressive symptoms.Female junior high school students were more likely to have anxiety and depressive symptoms.In addition,time spent on study was significantly and positively associated with anxiety and depressive symptoms and time spent on sleep was significantly and negatively associated with anxiety and depressive symptoms.Late sleepers were more likely to suffer from anxiety and depressive tendencies.Reducing after-school study time appropriately and getting more sleep are beneficial in reducing anxiety and depression,but it is more important to ensure time of sleep.For the reduction of anxiety and depressive symptoms,the maximum time spent on study after school should not exceed 1.92 h,the minimum time spent on sleep at night should be more than 7 h and a 40-min lunch break should be guaranteed at noon.展开更多
目的探讨紧张型头痛(tension type headache,TTH)患者发作期、发作间期触觉辨别能力的变化及机制。方法该研究为横断面研究。收集2023年10月至2024年2月在中国人民解放军总医院第一医学中心头痛门诊就诊的TTH患者,包括发作期和发作间期...目的探讨紧张型头痛(tension type headache,TTH)患者发作期、发作间期触觉辨别能力的变化及机制。方法该研究为横断面研究。收集2023年10月至2024年2月在中国人民解放军总医院第一医学中心头痛门诊就诊的TTH患者,包括发作期和发作间期各105例,另纳入109名志愿者作为健康对照组。收集受试者年龄、受教育时间、简易精神状态检查量表(mini-mental state examination,MMSE)、蒙特利尔认知评估量表(Montreal cognitive assessment,MoCA)、焦虑自评量表(self-rating anxiety scale,SAS)、抑郁自评量表(self-rating depression scale,SDS)评分等临床资料。通过触觉认知测试仪检测3组受试者的触觉辨别阈值,采用Kruskal-Wallis检验分析三组受试者触觉辨别阈值的差异。结果三组受试者年龄、受教育时间、MMSE、MoCA等一般资料差异无统计学意义(均P>0.05)。TTH患者合并焦虑抑郁者比例高于健康对照组(P<0.01)。通过协方差分析结果显示焦虑、抑郁与TTH对触觉辨别能力的影响的交互作用不显著。TTH患者发作期和发作间期组的触觉辨别阈值明显高于健康对照组(P<0.01),而TTH患者发作间期和发作期的触觉辨别阈值比较差异无统计学意义(P=1.000)。结论TTH患者发作期和发作间期的触觉认知水平均下降;触觉认知测试仪可识别TTH患者的早期触觉认知功能下降。展开更多
Hydrocarbon source rock obviously controls the formation and distribution of hydrocarbon reservoirs. Based on the geological concept of ＂source control theory＂, the concept of a hydrocarbon distribution threshold wa...Hydrocarbon source rock obviously controls the formation and distribution of hydrocarbon reservoirs. Based on the geological concept of ＂source control theory＂, the concept of a hydrocarbon distribution threshold was put forward. This means the maximum range for hydrocarbon controlled by the source rock conditions to migrate in the hydrocarbon basins. Three quantitative analysis models are proposed on this basis, namely the hydrocarbon accumulation probability, maximum hydrocarbon scale threshold and reserve distribution probability, which respectively refer to the probability of forming a hydrocarbon reservoir, the possible maximum scale of the hydrocarbon reservoir and the percentage of reserve distribution in a certain area within the hydrocarbon distribution threshold. Statistical analysis on 539 hydrocarbon reservoirs discovered in 28 hydrocarbon source kitchens from seven sedimentary basins and sags of eastern China shows the maximum reservoir scale possibly formed in the hydrocarbon basin, hydrocarbon accumulation probability and oil and gas reserve distribution probability are all controlled by the characteristics of the hydrocarbon source rock. Generally, as the distances from the hydrocarbon source rock center and hydrocarbon discharge boundary get longer and the hydrocarbon discharge intensity of hydrocarbon source rock center gets smaller, there will be lower probability of hydrocarbon accumulation. Corresponding quantitative models are established based on single factor statistics and multivariate analysis. Practical application in the Jiyang Depression shows that the prediction from the quantitative analysis model for the hydrocarbon distribution threshold agree well with the actual exploration results, indicating that the quantitative analysis model is likely to be a feasible tool.展开更多
文摘Research on effective source rocks directly affects the accuracy of identifying hydrocarbon resources, and indirectly affects the exploration decisions in petroliferous basins. Although the previous evaluation methods of effective source rocks vary relatively widely, a complete quantitative evaluation approach has not yet been developed. For that reason, we redefined the concept of effective source rocks based on the existing research results. Surrounding this definition, and guided by the hydrocarbon expulsion theory, the quantitative model called ＂two stages and three steps＂ method is established to predict effective source rocks. Its application in the Bozhong Depression indicates that among the four sets source rocks in the Bozhong Depression, the Member 3 of the Shahejie Formation （Es 3 ） has the largest effective source rock thickness, and the Member 1 Member 2 of the Shahejie Formation （Es 1＋2 ） is the second largest .The effective part of dark mudstone is only 30%-80% of the total volume and with the increase of buried depth and improvement of quality, the effective part increases. Comprehensive analysis indicates that the ＂two stages and three steps＂ method is a practical technique for effective source rock prediction.
文摘In the context of the COVID-19 pandemic and under the pressure of high competitiveness for higher education in China,junior high school students’mental health is facing greater challenges.Understanding the time allocation of study and sleep is necessary for developing effective prevention and treatment programs.Based on a survey of 31,057 junior high school students in 47 junior high schools in Gansu Province,China's Mainland,the study analyzed the associations of time spent on study and sleep with anxiety and depressive symptoms among junior high school students through chi-square test,ANOVA,logistic regression model and threshold regression model.It was found that 18.4%–21.1%of junior high school students had mild and above anxiety and depressive symptoms.Female junior high school students were more likely to have anxiety and depressive symptoms.In addition,time spent on study was significantly and positively associated with anxiety and depressive symptoms and time spent on sleep was significantly and negatively associated with anxiety and depressive symptoms.Late sleepers were more likely to suffer from anxiety and depressive tendencies.Reducing after-school study time appropriately and getting more sleep are beneficial in reducing anxiety and depression,but it is more important to ensure time of sleep.For the reduction of anxiety and depressive symptoms,the maximum time spent on study after school should not exceed 1.92 h,the minimum time spent on sleep at night should be more than 7 h and a 40-min lunch break should be guaranteed at noon.
基金supported by the National Natural Science Foundation Project(Grant No.41102085)the National Key Basic Research and Development 973 Program Project(Grant No.2011CB201105)+1 种基金Supported by Research Fund for the Doctoral Program of Higher Education of China(20110007120001)Supported by Science Foundation of China University of Petroleum, Beijing(No.KYJJ2012-01-08)
文摘Hydrocarbon source rock obviously controls the formation and distribution of hydrocarbon reservoirs. Based on the geological concept of ＂source control theory＂, the concept of a hydrocarbon distribution threshold was put forward. This means the maximum range for hydrocarbon controlled by the source rock conditions to migrate in the hydrocarbon basins. Three quantitative analysis models are proposed on this basis, namely the hydrocarbon accumulation probability, maximum hydrocarbon scale threshold and reserve distribution probability, which respectively refer to the probability of forming a hydrocarbon reservoir, the possible maximum scale of the hydrocarbon reservoir and the percentage of reserve distribution in a certain area within the hydrocarbon distribution threshold. Statistical analysis on 539 hydrocarbon reservoirs discovered in 28 hydrocarbon source kitchens from seven sedimentary basins and sags of eastern China shows the maximum reservoir scale possibly formed in the hydrocarbon basin, hydrocarbon accumulation probability and oil and gas reserve distribution probability are all controlled by the characteristics of the hydrocarbon source rock. Generally, as the distances from the hydrocarbon source rock center and hydrocarbon discharge boundary get longer and the hydrocarbon discharge intensity of hydrocarbon source rock center gets smaller, there will be lower probability of hydrocarbon accumulation. Corresponding quantitative models are established based on single factor statistics and multivariate analysis. Practical application in the Jiyang Depression shows that the prediction from the quantitative analysis model for the hydrocarbon distribution threshold agree well with the actual exploration results, indicating that the quantitative analysis model is likely to be a feasible tool.
