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Re-Examination of the Oil and Gas Origins in the Kekeya Gas Condensate Field,Northwest China——A Case Study of Hydrocarbon-Source Correlation Using Sophisticated Geochemical Methods

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 186-203页

作者： GONG Deyu WANG Zhaoyun LIU Gang CHEN Gang fang chenchen XIAO Zhongyao Research Institute of Petroleum Exploration and Development PetroChina Tarim Oilfield Company PetroChina

This work discussed the origins, alteration and accumulation processes of the oil and gas in the Kekeya gas condensate field based on molecular compositions, stable carbon isotopes, light hydrocarbons, diamondoid hydrocarbons and biomarker fingerprints. A comparison study is also made between the geochemical characteristics of the Kekeya hydrocarbons and typical marine and terrigenous hydrocarbons of the Tarim Basin. Natural gas from the Kekeya gas condensate field is derived from Middle–Lower Jurassic coal measures while the condensates are derived from Carboniferous–Permian marine source rocks with a higher maturity. In the study area, both natural gas and condensates have experienced severe water washing. A large amount of methane was dissolved into the water, resulting in a decrease in the dryness coefficient. Water washing also makes the carbon isotopic compositions of the natural gas more negative and partially reverse. Considering that the gas maturities are higher than once expected, gas generation intensity in the study area should be much stronger and the gas related to the Jurassic coal measures could promise a greater prospecting potential. As a result of evaporative fractionation, the Kekeya condensates are enriched in saturates and lack aromatics. Evaporative fractionation disguises the original terrigenous characteristics of the light hydrocarbons associated with the natural gas, making it appear marinesourced. Thus, alteration processes should be fully taken into consideration when gas–source correlations are carried out based on light hydrocarbons. With the condensates discovered in the study area all being ＂migration phase＂, the pre-salt Cretaceous and Jurassic reservoirs may promise great exploration potential for the ＂residual phase＂ hydrocarbons. This research not only is of significance for oil and gas exploration in the southwest Tarim Basin, but also sheds light on the oil/gas-source correlations in general.

关键词： Kekeya gas condensate field evaporative fractionation water washing coal-derived gas marine condensates stable carbon isotopes diamondoid hydrocarbons

Multiscale confinement nitridation in molybdenum carbide for efficient hydrogen production

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Journal of Energy Chemistry 2024年第7期94卷 61-69页

作者： Liming Dai chenchen fang Xiaoyuan Zhang Xuefeng Xu Xuanxuan Chen Xinyue Zong Xueming Hu Wenyao Zhang Liang Xue Pan Xiong Yongsheng Fu Jingwen Sun Junwu Zhu Key Laboratory for Soft Chemistry and Functional Materials Ministry of EducationNanjing University of Science and TechnologyNanjing 210094JiangsuChina

The molybdenum carbide(Mo_(2)C)has been regarded as one of the most cost-efficient and stable electrocatalyst for the hydrogen evolution reaction(HER)by the virtue of its Pt-like electronic ***,the inherent limitation of high density of empty valence band significantly reduces its catalytic reactivity by reason of strong hydrogen desorption ***,we propose a multiscale confinement synthesis method to design the nitrogen-rich Mo_(2)C for modulating the band structure via decomposing the pre-coordination bonded polymer in a pressure-tight tube sealing ***-bonded c/N-Mo in the coordination precursor constructs a micro-confinement space,enabling the homogeneous nitrogenization in-situ happened during the formation of Mo_(2)***,the evolved gases from the precursor decomposition in tube sealing system establish a macro-confinement environment,preventing the lattice N escape and further endowing a continuous *** the multiscale confinement effects,the nitrogen-rich Mo2C displays as high as 25%N-Mo concentration in carbide lattice,leading to a satisfactory band ***,the constructed nitrogen-rich Mo_(2)C reveals an adorable catalytic activity for HER in both alkaline and acid *** is anticipated that the multiscale confinement synthesis strategy presents guideline for the rational design of electrocatalysts and beyond.

关键词： Molybdenum carbide Hydrogen evolution reaction Multiscale confinement synthesis Valence band modulation Nitrogen doping

Can ECE Classes Sustainably Empower Preschool Children’s Development?-A Longitudinal Study of the Role of ECE Classes in Children’s Learning and Development

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Frontiers of Education in China 2024年第1期19卷 83-98页

作者： SHI Jin XUE Haiping fang chenchen College of Preschool Education Capital Normal UniversityBeijing 100048China College of Education Capital Normal UniversityBeijing 100048China Graduate School of Education Peking UniversityBeijing 100871China

Does enrolling children aged 0-3 in early childhood education(ECE)classes continuously empower their learning and development after entering kindergarten?Based on the tracking survey data of 664 children aged 3-6 in 2017 and 367 children aged 3-6 in 2018,this study uses Propensity Score Matching to analyze this *** findings reveal that children’s family socioeconomic status is a key factor influencing their participation in ECE *** baseline data show that participation in ECE classes does not significantly improve children’s learning and ***,the follow-up data show that participation in ECE classes plays a significant negative role in motor development for children moving to their second year of kindergarten,but subsequently plays a positive role in language development,health,and safety for those entering their third year of ***,participation in ECE classes plays no continuous positive role in children’s learning and development after they enter *** on these findings,it is suggested that parents should respect the natural laws of child development instead of blindly following the trend of attending ECE classes,and high-quality parental companionship is *** Chinese government is supposed to implement policies such as“double reduction”to regulate ECE institutions that fail to operate in good faith.

关键词： early childhood education(ECE)classes preschool children’s learning and development “double reduction”

The effect of volatile components in oil on evolutionary character- istics of diamondoids during oil thermal pyrolysis

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Science China Earth Sciences 2016年第10期59卷 362-370页

作者： fang chenchen XIONG YongQiang LI Yun LIANG QianYong WANG TongShan LI YongXin Research Institute of Petroleum Exploration and Development Beijing 100083 China State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangzhou Marine Geological Survey Ministry of Land and Resource Guangzhou 510760 China

On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(saturated, aromatic, resin, and asphalene fractions). However, little is known about the effect of volatile components in oil on diamondoid generation and diamondoid indices due to the lack of attention to these components in experiments. In this study, the effect of volatile components in oil on diamondoid generation and maturity indices was investigated by the pyrolysis simulation experiments on a normal crude oil from the HD23 well of the Tarim Basin and its residual oil after artificial volatilization, combined with quantitative analysis of diamondoids. The results indicate that the volatile components(≤n C12) in oil have an obvious contribution to the generation of adamantanes, which occurs mainly in the early stage of oil cracking(Easy Ro<1.0%), and influences the variations in maturity indices of adamantanes; but they have no obvious effect on the generation and maturity indices of diamantanes. Therefore, some secondary alterations e.g., migration, gas washing, and biodegradation, which may result in the loss of light hydrocarbons in oil under actual geological conditions, could affect the identification of adamantanes generated during the late-stage cracking of crude oil, and further influence the practical application of adamantane indices.

关键词： Crude oil Volatile component Thermal pyrolysis Diamondoids Evolution characteristics

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家庭背景、课外补习与学生非认知能力的关系研究——基于中国教育追踪调查数据的经验证据

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当代教育论坛 2018年第4期 39-46页

作者：方晨晨北京师范大学教育学部

基于中国教育追踪调查2014年数据,利用倾向得分匹配法和中介模型探讨课外补习对学生非认知能力的影响以及家庭背景、课外补习和学生非认知能力三者的路径机制,研究发现:参加课外补习的学生非认知能力平均得分明显高于未参加课外补习的... 详细信息

基于中国教育追踪调查2014年数据,利用倾向得分匹配法和中介模型探讨课外补习对学生非认知能力的影响以及家庭背景、课外补习和学生非认知能力三者的路径机制,研究发现:参加课外补习的学生非认知能力平均得分明显高于未参加课外补习的学生。采用倾向得分匹配法分析发现,学生参加课外补习有助于提高非认知能力,兴趣类课外补习对学生非认知能力的影响效应高于学术类课外补习。兴趣类课外补习在家庭社会经济地位对学生非认知能力影响过程中起到了部分中介效应,而学术类课外补习并没有显著的中介效应。因此,一方面家庭应更多的选择兴趣类课外补习进行投资,提高学生非认知能力。另一方面学校应加强美育教育,重视学生非认知能力的培养。

关键词：家庭背景课外补习非认知能力倾向得分匹配法中介模型

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2000年以来中国大气田勘探开发特征

天然气工业 2015年第1期35卷 1-9页

作者：戴金星吴伟房忱琛刘丹中国石油勘探开发研究院

截至2013年底,中国共探明51个大气田,天然气储量持续高峰增长、产量快速上升、管网建设蓬勃发展、市场需求旺盛。总结2000年以来中国大气田勘探、开发的特征,可以为发现更多的大气田提供借鉴和思路。中国大气田勘探特征:仅发现于沉积面... 详细信息

截至2013年底,中国共探明51个大气田,天然气储量持续高峰增长、产量快速上升、管网建设蓬勃发展、市场需求旺盛。总结2000年以来中国大气田勘探、开发的特征,可以为发现更多的大气田提供借鉴和思路。中国大气田勘探特征:仅发现于沉积面积大于10×10~4km^2的盆地,已在9个盆地中探明了大气田;2005年前大气田探明天然气总储量较少,为2.708588×10^(12)m^3,之后则较大,2013年底探明天然气总储量为8.168377×10^(12)m^3;大气田储量丰度最大的和最小的相差超过86倍,储量丰度最大的克拉2气田为59.05×10~8m^3/km^2,最小的靖边气田为0.684×10~8m^3/km^2;深度介于3000~4500m的大气田探明储量比例大,占总储量的46.11%。中国大气田开发特征:大气田的产量是中国天然气工业的支柱,2013年大气田总产量达922.72×10~8m^3,占全国天然气总产量的76.3%;大气田的产量中以煤成气为主,2013年大气田中煤成气总产量为710.13×10~8m^3,煤成气占全国大气田总产量的77.0%;关键大气田(苏里格、靖边、大牛地、普光、克拉2等气田)的产量是支撑产气大国的基石。

关键词：中国大气田煤成气勘探开发储量产量沉积面积产层深度

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基于改进深度残差网络的番茄病害图像识别

计算机应用 2020年第S1期40卷 203-208页

作者：方晨晨石繁槐同济大学电子与信息工程学院上海201804

针对大多数深度卷积神经网络(DCNN)模型存在内存占用较多、计算资源消耗大的问题,提出一种基于改进深度残差网络(DRN)的番茄病害图像识别方法。该网络模型在传统残差神经网络的基础上,采用多尺度卷积代替原始网络结构中的单一尺度卷积,... 详细信息

针对大多数深度卷积神经网络(DCNN)模型存在内存占用较多、计算资源消耗大的问题,提出一种基于改进深度残差网络(DRN)的番茄病害图像识别方法。该网络模型在传统残差神经网络的基础上,采用多尺度卷积代替原始网络结构中的单一尺度卷积,使得提取的特征更加丰富,并拓展了网络宽度,避免因网络过深引起的退化问题。为了进一步降低模型对内存占用的需求,用深度可分离卷积替换部分标准卷积,在不损失网络性能的前提下减少模型参数。为验证改进后深度残差网络模型提升番茄病害识别性能的有效性,对获得的有限番茄病害叶片图像数据集进行了样本扩充,并基于扩充后的数据集使用改进模型与几个常见深度神经网络模型进行对比实验。结果表明,改进后的深度残差网络模型可以很好地实现番茄病害的识别,平均测试识别准确率达到98.58%,且训练后的模型仅占19.0 MB,有助于将来在低性能终端上实现对番茄病害的实时诊断。

关键词：番茄病害图像识别卷积神经网络深度残差网络

高考升学竞争与学生课外补习——基于中国家庭追踪调查数据的实证分析

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北京大学教育评论 2020年第3期18卷 172-186,192页

作者：薛海平方晨晨首都师范大学教育学院北京100048 北京大学教育学院北京100871

本文基于中国家庭追踪调查2016年数据和各省高考本科录取率数据,利用多层线性伯努利模型,对各省高考升学竞争与基础教育阶段学生课外补习参与的关系进行探究。研究发现:(1)各省基础教育阶段学生课外补习参与率随着各省本科生录取率的上... 详细信息

本文基于中国家庭追踪调查2016年数据和各省高考本科录取率数据,利用多层线性伯努利模型,对各省高考升学竞争与基础教育阶段学生课外补习参与的关系进行探究。研究发现:(1)各省基础教育阶段学生课外补习参与率随着各省本科生录取率的上升而上升,另一方面,又随着各省重点高校录取占比的上升而下降。(2)各省本科生录取率对学生参与课外补习有显著正影响,而重点高校录取占比对学生参与课外补习有显著负影响。(3)高校本科录取率对不同家庭社会经济背景学生参与课外补习影响存在异质性,但对不同阶段学校学生参与课外补习影响不存在异质性。普通高校本科招生规模扩张加深了学生和家长的高考升学竞争焦虑,促使基础教育各阶段学校学生更多参与课外补习以图进入重点大学,尤其是来自社会经济地位较高家庭的学生更倾向于选择课外补习以维持高考升学竞争优势。

关键词：课外补习教育竞争高考升学教育公平

家庭劳动对初中生能力发展的影响--基于CEPS数据的实证研究

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湖南师范大学教育科学学报 2021年第2期20卷 56-63,89页

作者：方晨晨曹连喆北京大学教育学院北京100871 首都师范大学教育学院北京100037

基于中国教育追踪调查基线数据,研究通过构建多层线性模型,分析我国初中生家庭劳动现状,探究家庭劳动与初中生能力发展的关系。研究发现:12.1%的初中生不参与家庭劳动,且不同特征的初中生家庭劳动时间存在显著差异;1小时以内的家庭劳动... 详细信息

基于中国教育追踪调查基线数据,研究通过构建多层线性模型,分析我国初中生家庭劳动现状,探究家庭劳动与初中生能力发展的关系。研究发现:12.1%的初中生不参与家庭劳动,且不同特征的初中生家庭劳动时间存在显著差异;1小时以内的家庭劳动有助于提高初中生学业成绩和认知能力;家庭劳动对初中生开放性、外倾性和宜人性等非认知能力有显著正向影响,有利于促进学生非认知能力的发展。因此,家长要重视劳动教育,在家庭教育中有机融入劳动教育,并且需遵循学生身心发展规律,开展合适的家庭劳动。同时,各方要积极构建以家庭为主体,以学校为引导,以社区为支持的内外交织、多元协同的家庭劳动教育体系。

关键词：家庭劳动学业成绩认知能力非认知能力