检索结果-南通市图书馆

Evolution and generation mechanism of retained oil in lacustrine shales: A combined ReaxFF-MD and pyrolysis simulation perspective

引用

Petroleum Science 2025年第1期22卷 29-41页

作者： Biao Sun Xiao-Ping Liu Jie Liu Tian Liu Zu-Xian Hua wen-Di peng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) College of Geosciences China University of Petroleum (Beijing) International Petroleum Exploration and Production Corporation SINOPEC

To accurately investigate the evolution characteristics and generation mechanism of retained oil, the study analyzed organic-rich lacustrine shale samples from the Paleogene Kongdian Formation in Cangdong Sag, Bohai Bay Basin. This analysis involves Rock-Eval pyrolysis, pyrolysis simulation experiments,Gas Chromatograph Mass Spectrometer（GC-MS）, and reactive molecular dynamics simulations（Reax FF）. The results revealed the retained oil primarily consisted of n-alkanes with carbon numbers ranging from C14to C36. The generation of retained oil occurred through three stages. A slow growth stage of production rate was observed before reaching the peak of oil production in Stage I. Stage II involved a rapid increase in oil retention, with C12-C17and C24-C32serving as the primary components,increasing continuously during the pyrolysis process. The generation process involved the cleavage of weak bonds, including bridging bonds（hydroxyl, oxy, peroxy, imino, amino, and nitro）, ether bonds, and acid amides in the first stage（Ro= 0.50%-0.75%）. The carbon chains in aromatic ring structures with heteroatomic functional groups breaks in the second stage（Ro= 0.75%-1.20%）. In the third stage（Ro= 1.20%-2.50%）, the ring structures underwent ring-opening reactions to synthesize iso-short-chain olefins and radicals, while further breakdown of aliphatic chains occurred. By coupling pyrolysis simulation experiments and molecular simulation technology, the evolution characteristics and bond breaking mechanism of retained oil in three stages were revealed, providing a reference for the formation and evolution mechanism of retained oil.

关键词： Lacustrine shale Retained oiliness evolution Pyrolysis simulation experiments ReaxFF molecular dynamics Hydrocarbon generation evolution

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

考虑热力耦合的轨道车辆车轮建模与仿真

引用

交通运输工程学报 2016年第5期16卷 30-41页

作者：文永蓬徐小峻尚慧琳李琼上海工程技术大学城市轨道交通学院上海201620 上海应用技术大学机械工程学院上海201418

以城市轨道车辆车轮为研究对象,建立了S型辐板轨道车辆车轮模型,利用有限元方法研究了不同磨耗情况下车轮结构应力和热应力的变化特点,分析了结构场和温度场的耦合作用对车轮应力特性的影响,获得了热力耦合作用下的车轮结构应力和热应... 详细信息

以城市轨道车辆车轮为研究对象,建立了S型辐板轨道车辆车轮模型,利用有限元方法研究了不同磨耗情况下车轮结构应力和热应力的变化特点,分析了结构场和温度场的耦合作用对车轮应力特性的影响,获得了热力耦合作用下的车轮结构应力和热应力的耦合规律。仿真结果表明：随着车轮踏面的磨耗,其结构应力、热应力与耦合应力均呈非线性变化,在车轮直径为800～840mm的磨损区间,耦合应力较稳定,当磨损到直径小于800mm之后,其耦合应力增长较快,特别是磨耗到770mm时,耦合应力骤升,磨耗到限时耦合应力达到179.5 MPa;车轮的耦合应力是复杂的三维空间力系的叠加,在耦合应力分布上,车轮辐板处耦合应力最大点位置发生漂移现象,制动结束时的车轮辐板处耦合应力最大,大于结构应力最大值与热应力最大值,因此,耦合应力在车轮应力中占主导作用,在车轮的结构设计时,建议考虑结构应力和热应力的耦合作用,把耦合应力作为车轮疲劳强度的评价指标。

关键词：轨道车辆车轮热力耦合结构场温度场磨耗

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A single-pixel elemental imaging method using neutron-induced gamma-ray activation

引用

Nuclear Science and Techniques 2025年第1期36卷 1-12页

作者： Can Cheng yong-Ji Xie Xun-Rong Xia Jia-Yu Gu Dong Zhao Yi-Ze Chen Ai-Yun Sun Xu-wen Liang wen-Bao Jia Da-Qian Hei Department of Ionizing Radiation and Medical Engineering Jiangsu Institute of MetrologyNanjing 210023China Institute of Nuclear Analytical Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China China Nuclear Power Engineering Co. LtdBeijing 100840China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Neutron-induced gamma-ray imaging is a spectroscopic technique that uses characteristic gamma rays to infer the elemental distribution of an ***,this technique requires the use of large facilities to supply a high neutron flux and a time-consuming detection procedure involving direct collimating *** this study,a new method based on low neutron flux was proposed.A single-pixel gamma-ray detector combined with random pattern gamma-ray masks was used to measure the characteristic gamma rays emitted from the *** of the elemental distribution in the sample,comprising 30×30 pixels,were reconstructed using the maximum-likelihood expectation-maximization *** results demonstrate that the elemental imaging of the sample can be accurately determined using this *** proposed approach,which eliminates the need for high neutron flux and scanning measurements,can be used for in-field imaging applications.

关键词： Elemental imaging Neutron-induced gamma-ray activation Single-pixel imaging

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Facilitation of microbialite development by continental weathering in the Cambrian Zhangxia Formation,southern North China Block

引用

Journal of Palaeogeography 2025年第1期14卷 172-185页

作者： wen-Tao Yang Jia-Qi Zhu Min Wang Chao Liu yong-An Qi School of Resources and Environment Henan Polytechnic University Key Laboratory of Biogenic Traces and Sedimentary Minerals of Henan Province Henan Polytechnic University State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences

We report geochemical data for carbonate rocks from the Cambrian Zhangxia Formation,southern North China Block,including trace-element contents and C,O,and Sr isotopic compositions,to determine the controls on the development of microbialites in this *** sedimentary environment of the Zhangxia Formation evolved from carbonate-slope through platform-margin-reef to ooid-shoal,and then to open-platform settings,corresponding to the development of micrites,microbialites,and oolitic *** data show that δ13C values decrease upwards through the Zhangxia Formation,from 0.99‰to-1.59‰,whereas δ18O values increase from-9.91‰to-7.10‰.Total rare earth element （REE）contents decrease upwards through the stratigraphy,and the contents of Th and Sc show a similar trend.87Sr/86Sr ratios reach a maximum of 0.710544 in the horizons of microbialite development,Member 2 of the Zhangxia Formation,above which the ratios are uniform,with a mean value of *** these geochemical data with the inferred sedimentary evolution,the Zhangxia Formation is interpreted to have formed in a depositional environment that changed from transgression to *** weathering played a crucial role in promoting the input of terrigenous materials,which in turn favored the development of microbialites during the early stage of deposition of the Zhangxia Formation.

关键词： Carbonate rocks Trace elements C and Sr isotopes Microbialites Cambrian

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

间接连接型音叉振动式微机械陀螺的性能变异分析

引用

机械设计与制造 2013年第7期 80-83页

作者：文永蓬尚慧琳上海工程技术大学城市轨道交通学院上海201620 上海应用技术学院机械工程学院上海200235

以一种间接连接型音叉振动式微机械陀螺为研究对象,分析了加工误差引起的关键参数的性能变异对检测输出电容的影响。通过对这种微机械陀螺的检测原理介绍并对其动力学进行分析,获得了误差检测模型输出电容表达式。结果表明,这种微机械... 详细信息

以一种间接连接型音叉振动式微机械陀螺为研究对象,分析了加工误差引起的关键参数的性能变异对检测输出电容的影响。通过对这种微机械陀螺的检测原理介绍并对其动力学进行分析,获得了误差检测模型输出电容表达式。结果表明,这种微机械陀螺检测微弹性梁弹性系数的变异引起的不对称对系统输出具有较大的影响,加工中对检测微弹性梁应引起足够的重视。工作为间接连接型音叉振动式微机械陀螺加工性能的提高具有一定的参考价值。

关键词：微机械微机械陀螺间接连接性能变异加工误差

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

服役条件下车-设备耦合的地铁车辆横向振动特性

引用

交通运输工程学报 2024年第4期24卷 161-170页

作者：文永蓬吴俊汉钟硕乔宗志祥周慧上海工程技术大学城市轨道交通学院上海201620 上海工程技术大学上海市轨道交通振动与噪声控制技术工程研究中心上海201620 上海地铁维护保障有限公司车辆分公司上海200235

为了降低车体的横向振动,提高长期服役过程中的地铁车辆乘坐舒适性,建立了含车下设备的地铁车辆横向动力学模型,调研了车辆行驶速度分布以及反映轮轨接触状态的等效锥度在服役条件下的动态变化规律,获得了车-设备耦合下的横向振动特性,... 详细信息

为了降低车体的横向振动,提高长期服役过程中的地铁车辆乘坐舒适性,建立了含车下设备的地铁车辆横向动力学模型,调研了车辆行驶速度分布以及反映轮轨接触状态的等效锥度在服役条件下的动态变化规律,获得了车-设备耦合下的横向振动特性,形成了车-设备耦合的车体横向减振参数设计方法。研究结果表明:地铁车辆的服役条件会随着车辆的行驶速度和等效锥度改变而动态改变,逐渐增大的轮轨接触等效锥度会导致车辆临界速度降低,加剧车辆的横向振动,横向振动的特征频率会随行驶速度和等效锥度的提高而线性增大,其数值集中在低频1~3 Hz范围;车体与设备在横向发生振动耦合时,设备的质量与弹性悬挂刚度存在最优匹配关系,选取合适的悬挂刚度能显著降低车体的横向振动,适当增加车下设备宽度和侧滚惯量,有助于降低车体的横向振动,为了抑制车-设备的横向振动,要重视横向悬挂刚度的选取,建议选取6.0×10^(4)N·m^(-1);车下设备与车体之间采用合适的弹性悬挂连接,让设备横向振动频率与车体的横向振动频率接近,利用车-设备的同频耦合振动,能够降低车体的横向振动,有利于车辆运行品质的提升。

关键词：车辆工程地铁车辆车下设备蛇行运动横向振动弹性悬挂耦合振动

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

考虑UIC强度准则的轨道车轮辐板渐进结构拓扑优化方法

引用

交通运输工程学报 2019年第5期19卷 84-95页

作者：郑晓明文永蓬尚慧琳刘跃杰上海工程技术大学城市轨道交通学院上海201620 上海应用技术大学机械工程学院上海201418

为了提高轨道车轮的结构性能,利用渐进结构拓扑优化方法(ESO)建立了轨道车轮的结构优化模型;以双S型轨道车轮为设计蓝本,分析了轨道车轮的辐板设计域,提出了轨道车轮在多工况作用下的渐进结构拓扑优化方法;介绍了利用渐进结构拓扑优化... 详细信息

为了提高轨道车轮的结构性能,利用渐进结构拓扑优化方法(ESO)建立了轨道车轮的结构优化模型;以双S型轨道车轮为设计蓝本,分析了轨道车轮的辐板设计域,提出了轨道车轮在多工况作用下的渐进结构拓扑优化方法;介绍了利用渐进结构拓扑优化方法实现结构应力均匀化的优化思路;根据《整体车轮技术检验》(UIC 510-5:2003)标准,分别考虑了轨道车轮在直线工况、曲线工况和道岔通过工况,不仅获得这3种典型工况共同作用下的拓扑优化结构,而且还获得了3种典型工况依次作用下的6种拓扑结构;对比了优化前后车轮辐板的应力,并利用有限元工具验证了优化后车轮的辐板应力特性,证明渐进结构拓扑优化方法的正确性和有效性。研究结果表明:利用渐进结构拓扑优化方法对轨道车轮的拓扑优化是适用的;在车轮质量不增加的前提下,优化后车轮辐板的厚度增加且不等厚,有效地减小应力集中,降低结构应力;对比原双S型车轮,优化后6种车轮模型的结构性能均有所提升,分别提高了16.6%、20.7%、22.5%、21.3%、20.1%和19.5%,其中,方案3的优化车轮在3种工况下辐板处的最大结构应力分别降低了4.0%、14.5%和6.7%。研究有助于轨道车轮结构强度的提高,并对多工况耦合作用下轨道车轮结构优化具有重要的参考价值。

关键词：车辆工程轨道车轮渐进结构优化拓扑优化多工况结构应力

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Changes in River Cross-section Morphology and Response to Streamflow and Sediment Processes in Middle Reaches of Yellow River,China

引用

Chinese Geographical Science 2025年第1期35卷 161-174页

作者： wen yongfu LI pengfei LI Mengzhen MA Chaohui GAO peng MU Xingmin ZHAO Guangju The Research Center of Soil and Water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences&Ministry of Water ResourcesYangling 712100China University of Chinese Academy of Sciences Beijing 100049China Hebei University of Water Resources and Electric Engineering Cangzhou 061001China Xi’an University of Science and Technology Xi’an 710054China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China

Changes in river cross-section morphology have decisive influences on the flood discharge and sand transport capacity of rivers;thus,these changes strongly reflect the vitality of a *** this paper,based on the river cross-section and water and sediment data of two different periods(1974−1987 and 2007−2021),the trend analysis,change-point analysis and sediment rating curve method were used to analyze the change process of river cross-section morphology and its response to streamflow and sediment changes in the main river stream of the Yellow River at the Longmen hydrological *** 1974 to 1987(except in 1977),the riverbed experi-enced siltation,and the riverbed elevation ***,from 2007 to 2021,the riverbed experienced scouring,and the riverbed el-evation gradually *** cross-section shape changed from rectangular to U-shaped(deeper on the right side)at the Longmen *** changes in streamflow and sediment processes significantly impacted the evolution of river ***-flow(P<0.05),sediment discharge(P<0.01),and the sediment load coefficients(P<0.01)decreased *** relationship between the water depth and sediment load coefficients followed a power *** decreasing trend in sediment discharge was sig-nificantly stronger than that in *** sediment particles tended to become *** sediment rating curve indicates that the sediment supply from upstream decreased while the erosive power in the river channel increased,leading to a gradual decline in riverbed elevation at the Longmen cross-section from 2007 to *** findings help us better understand the impacts of ecological restoration on changes in river streamflow and sediment during river evolution.

关键词： cross-section shape riverbed elevation water depth streamflow sediment discharge eco-restoration Longmen station middle reaches of the Yellow River,China

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Visualization of the protective role of estrogen against female liver fibrosis via an ER viscosity NIR fluorescent probe

引用

Science China Chemistry 2025年第1期68卷 360-368页

作者： Zheng Liu Changyu Zhang Zipeng Li Wanying Ma Jia Liu Xiang Xia Ning Xu wen Sun Jianjun Du Jiangli Fan Xiaojun peng State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China Ningbo Institute of Dalian University of Technology Ningbo 315016China

Endoplasmic reticulum(ER)viscosity has emerged as a new potential biomarker for hepatic fibrosis(HF).Herein,we report the first ER-targeting viscosity-responsive near-infrared(NIR)fluorescent probe HBT-PP for investigations of HF *** twisted intramolecular charge transfer(TICT)and the excited state intramolecular proton transfer(ESIPT)are combined to endow HBT-PP with the selective response towards viscosity(~62-fold)and a super large stokes shift(~320 nm).HBT-PP mainly targets organelle ER and is able to image the drug-or alcohol-induced viscosity elevation in living ***,HBT-PP was successfully applied to visualize the gender difference in HF and the protective role of estrogen in restraining HF *** note,after 10 min of stain with HBT-PP,HF lesions showed a stage-based response,indicating the potential of this probe in fast and early diagnosis of *** results clearly demonstrated the promising application of HBT-PP as a new tool for exploring ER viscosity-involved physiological and pathological processes.

关键词： NIR fluorescent probe ER viscosity hepatic fibrosis gender difference estrogen

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Flow behavior and dynamic softening mechanism of Pt−10Ir precious alloy

引用

Transactions of Nonferrous Metals Society of China 2025年第1期35卷 225-242页

作者： Xin-pei ZHANG Jun-jie HE Lin PI Quan FU wen-yan ZHOU Jun CHENG Sheng-wen BAI Xuan ZHOU Yi LIU yong MAO Materials Genome Institute School of Materials and EnergyYunnan UniversityKunming 650091China Kunming Precious Materials&Technology Co. Ltd.Yunnan Precious Metals Laboratory Co.Ltd.Sino-Platinum Metals Co.Ltd.Kunming 650106China Kunming Institute of Precious Metals Kunming 650106China State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals Sino-Platinum Metals Co.Ltd.Kunming 650106China Shaanxi Key Laboratory of Biomedical Metal Materials Northwest Institute for Non-ferrous Metal ResearchXi’an 710016China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The hot deformation behavior of Pt−10Ir alloy was studied under a wide range of deformation *** a low deformation temperature(950−1150℃),the softening mechanism is primarily dynamic *** addition,dynamic recrystallization by progressive lattice rotation near grain boundaries(DRX by LRGBs)and microshear bands assisted dynamic recrystallization(MSBs assisted DRX)coordinate the ***,it is difficult for the dynamic softening to offset the stain hardening due to a limited amount of DRXed *** a high deformation temperature(1250−1350℃),three main DRX mechanisms associated with strain rates occur:DRX by LRGBs,DRX by a homogeneous increase in misorientation(HIM)and geometric DRX(GDRX).With increasing strain,DRX by LRGBs is enhanced gradually under high strain rates;the“pinch-off”effect is enhanced at low strain rates,which was conducive to the formation of a uniform and fine microstructure.

关键词： platinum alloy hot deformation microstructure evolution dynamic recovery dynamic recrystallization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：