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基于场景频率的石化装置气体探测覆盖率评估

中国安全生产科学技术 2024年第2期20卷 97-103页

作者：王雅真凌晓东慕云涛刘迪张云燕化学品安全全国重点实验室山东青岛266071 中石化安全工程研究院有限公司山东青岛266071 中石化国家石化项目风险评估技术中心有限公司山东青岛266071

为解决现有评估方法未能定量分析泄漏场景发生频率在石化过程模块中的分布不均匀性,提出1种基于场景频率的石化装置气体探测覆盖率评估方法,包括典型泄漏场景库构建、基于计算流体动力学(CFD)的气体泄漏扩散行为仿真以及基于场景频率的... 详细信息

为解决现有评估方法未能定量分析泄漏场景发生频率在石化过程模块中的分布不均匀性,提出1种基于场景频率的石化装置气体探测覆盖率评估方法,包括典型泄漏场景库构建、基于计算流体动力学(CFD)的气体泄漏扩散行为仿真以及基于场景频率的探测覆盖率计算3个步骤;提出1种定量筛选方法以选择更具代表性的高频泄漏场景,在表征装置泄漏场景特点的同时节约计算资源。研究结果表明:通过引入泄漏场景频率对覆盖率评估计算公式进行升级,案例分析结果显示该计算方法能够更加真实准确地对气体探测系统有效性进行评估。研究结果可提高石化装置气体探测覆盖率评估工作的效率及准确性。

关键词：安全工程技术 GDS系统场景频率气体扩散仿真场景探测覆盖率

Organic geochemistry and petrology of source rocks from the Banqiao Sag, Bohai Bay Basin, China: Implications for petroleum exploration

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Petroleum Science 2022年第4期19卷 1505-1515页

作者： Xiang-Bai liu Guang-di liu Wen-Ya Jiang Ze-Zhang Song Na Wang State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Geosciences China University of PetroleumBeijing102249China Exploration and Development Research Institute Dagang Oilfield CompanyPetroChinaTianjin300280China

The organic geochemistry and petrology of source rocks determine the hydrocarbon generation potential of the Banqiao Sag. In this study, organic geochemistry and petrology were used to determine the abundance of organic matter(OM), OM type, OM maturity, and sedimentary environments of the source rocks, collected from Cenozoic Shahejie Formation, Banqiao Sag, Bohai Bay Basin, China. Vitrinite and liptinite are the main maceral composition of the source rocks, and range from 18% to 81% and from 2% to82% on a mineral matter free(MMF) basis, respectively. The values of vitrinite reflectance(Ro)(0.36%-1.20%) and the Tmaxvalues(397-486.C) show that the thermal maturity range from low mature to peak-maturity. The abundance of OM varies between 0.22% and 4.37%, suggesting that the source rocks of the Shahejie(Es) Formation are mainly fair to good source rocks. The Rock-Eval pyrolysis results show that the source rocks have good petroleum generation potential. The amount of free hydrocarbons(S_1)and hydrocarbons generated from pyrolysis(S_(2)) range within 0.01-3.70 mg/g, and 0.04-29.17 mg/g. The hydrogen index(HI) varies between 18.18 and 741.13 mg HC/g TOC, with most of the samples appearing to be mainly Type II kerogen, and thereby exhibiting the ability to generate both oil and gas. The ratios of Pr/Ph, the cross plot of Pr/nC_(17)-Ph/nC_(18), the cross plot of C_(29)/C_(27)-Pr/Ph, and ternary of dibenzothiophene, dibenzofuran, and fluorene, indicate that the Shahejie Formation deposited in suboxic and weak reducing environments. The main biological source is from advanced plants. The maceral composition and rock pyrolysis data indicate the kerogen type is a humic type or mixed sapropelic-humic type. The source rocks of the Shahejie(Es) Formation occur in the oil window, and the abundant organic richness,humic kerogen demonstrate that these rocks are effective oil and gas source rocks. The mudstone rocks in the Shahejie Formation are the main source of oil and gas and re

关键词： Lacustrine source rocks Petrology Biomarkers Depositional environment Banqiao Sag

Critical Transition Reynolds Number for the Incompressible Flat-plate Boundary Layer as Searched by Numerical Simulation

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Advances in Applied Mathematics and Mechanics 2023年第4期15卷 1056-1075页

作者： Yongming Zhang di liu Ning Li Laboratory for High-Speed Aerodynamics Tianjin UniversityTianjin 300072China Department of Mechanics Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300072China Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China

The critical transition Reynolds number is the lowest value at which the turbulent flow can hold in real *** determination of the critical transition Reynolds number not only is a scientific problem,but also is important for some engineering ***,there is no available theoretical method to search the critical *** the hypersonic boundary layer with significant importance for engineering problems,there is no available experimental method to search the critical value so ***,it is imperative to take numerical method to search *** this paper,direct numerical simulations(DNS)method is employed to determine the critical transition Reynolds number for the incompressible flat-plate boundary ***,under the assumption of parallel flow,the temporal mode DNS is performed to determine the critical value as Re_(xpcr)=43767,which is quite close to the numerical results of other ***,under the condition of nonparallel flow,the spatial mode DNS is performed to determine the critical transition Reynolds number as Re_(xcr)=3×10^(5),which is well consistent with the experimental *** principle,the proposed method in this paper can be extended to the supersonic/hypersonic boundary layer,and that problem will be discussed in the subsequent papers.

关键词： Critical transition Reynolds number flat-plate boundary layer DNS temporal mode spatial mode

中药山慈菇基原物种生态适宜性关键生态因子及区划研究

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世界科学技术-中医药现代化 2024年第5期26卷 1254-1260页

作者：池玉洁朱明玉刘义飞刘迪森林胡志刚张景景湖北中医药大学药学院

目的为山慈菇基原物种科学引种和选址扩种提供理论基础。方法通过查询多个数据库和实地调查，收集山慈菇基原物种在全国范围内的257个有效分布数据。综合海拔、温度、太阳辐射、降雨量和水汽压5个类别共68个生态因子，利用Maxent和Arc... 详细信息

目的为山慈菇基原物种科学引种和选址扩种提供理论基础。方法通过查询多个数据库和实地调查，收集山慈菇基原物种在全国范围内的257个有效分布数据。综合海拔、温度、太阳辐射、降雨量和水汽压5个类别共68个生态因子，利用Maxent和ArcGIS对山慈菇基原物种的生态适宜性进行分析。结果分析得到影响山慈菇生态适宜性的关键生态因子主要是降雨量、太阳辐射以及海拔，不同基原物种间关键生态因子有显著差异。最适宜杜鹃兰、独蒜兰以及云南独蒜兰生长的潜在区域分别集中在台湾、华南地区以及云南四川相接一带。结论本研究进一步对其潜在分布区分别进行了生态适宜性等级划分，为山慈菇合理引种栽培及人工规范化扩种提供科学依据。

关键词：山慈菇 Maxent模型及ArcGIS 生态因子生态适宜性

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考虑频响函数混叠误差的阻尼比识别效果研究

东南大学学报（自然科学版） 2024年第1期54卷 126-134页

作者：曲春绪屠桂凯高富忠伊廷华李宏男刘迪周海俊李文全大连理工大学土木工程学院大连116024 中铁第四勘察设计院集团有限公司线路站场设计研究院武汉430063 深中通道管理中心中山528411 极端环境绿色长寿道路工程全国重点实验室深圳518060 辽宁省交通规划设计院有限责任公司沈阳110111

通过实测频响函数识别阻尼比时,识别准确性受到频谱混叠现象的影响,因此建立了考虑频响函数混叠误差的阻尼比识别有效性判断方法.首先,根据傅里叶变换原理进行理论推导,证明了采样频率不足时频响函数会发生混叠现象;然后,根据频响函数... 详细信息

通过实测频响函数识别阻尼比时,识别准确性受到频谱混叠现象的影响,因此建立了考虑频响函数混叠误差的阻尼比识别有效性判断方法.首先,根据傅里叶变换原理进行理论推导,证明了采样频率不足时频响函数会发生混叠现象;然后,根据频响函数混叠原理和模态叠加原理,建立了多自由度结构的基准频响混叠误差拟合公式,进而给出考虑频响函数混叠误差的阻尼比识别结果有效性判断的步骤.通过对两自由度理论频响函数模型设置不同的等效柔度比和固有频率比,表明其对两阶模态计算频响混叠误差有显著影响;通过对比四层框架结构基准模型的响应在设置不同采样频率时对阻尼比的识别结果,验证了所提方法的可行性.

关键词：采样频率频谱混叠频响函数阻尼比识别傅里叶变换

One-step post-treatment boosts thermoelectric properties of PEDOT:PSS flexible thin films

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Journal of Materials Science & Technology 2023年第1期132卷 81-89页

作者： Xingyu liu Xiao-Lei Shi Li Zhang Wei-di liu Yanling Yang Zhi-Gang Chen School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China School of Chemistry and Physics Queensland University of TechnologyBrisbaneQLD 4000Australia Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbaneQLD 4072Australia

Developing high-performance poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)sig-nificantly widens the practical applications of flexible organic thermoelectric devices,while the water-based co-solvent dopants and/or post-treatments are still rarely studied so ***,we develop a one-step post-treatment to improve the power factor of PEDOT:PSS films by using a water-based solution,which is composed of co-solvent(polar solvent dimethylacetamide(DMAC)and deionized water)and organic reducing agent L-ascorbic acid(LAA).The 80 vol.%DMAC solution significantly boosts the room-temperature electrical conductivity of the films from 5 to 964 S cm^(−1),while the Seebeck coefficient can be further enhanced from 18.7 to 25μV K−1 by treating with 0.5 mol L−1 LAA,contributing to a sig-nificantly improved power factor of 55.3μW m^(−1)K^(−2).The boosted electrical conductivity is ascribed to the separated PEDOT and PSS phases triggered by the high dielectric constant and polarity of DMAC;while the improved Seebeck coefficient is attributed to the reduced oxidation degree of PEDOT from the reducing agent LAA,both confirmed by the comprehensive structural and morphological ***,a maximum power factor of 64.4μW m^(−1)K^(−2)can be achieved at 360 K and the observed temperature-dependent electrical transport behavior can be well explained by the Mott variable range hopping ***,a flexible thermoelectric device,assembled by the as-fabricated PEDOT:PSS films,exhibits a maximum output power of∼23 nW at a temperature difference of 25 K,indicating the potential for applying to low-grade wearable electronics.

关键词： Thermoelectric PEDOT:PSS Post-treatment dimethylacetamide L-ascorbic acid

A recursive least squares algorithm with ?1 regularization for sparse representation

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Science China(Information Sciences) 2023年第2期66卷 281-282页

作者： di liu Simone BALdi Quan liu Wenwu YU School of Cyber Science and Engineering Southeast University School of Computation Information and Technology Technical University of Munich School of Mathematics Center for Mobile Communication and Security Southeast University School of Artificial Intelligence Southeast University

Sparse representation aims to identify a few basic elements in a signal, so as to use a combination of such elements to reconstruct the original signal. The ?1-norm has been widely applied in sparse representation, either when processing batches of data offline, or online as in adaptive filtering [1–3]. Representative algorithms for online sparse representation include zero-attracting LMS(ZA-LMS) [4],?1-RLS [5], ?1-RRLS [6], zero-attracting RLS(ZA-RLS) [7],

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Recent advances in high-performance triboelectric nanogenerators

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Nano Research 2023年第9期16卷 11698-11717页

作者： di liu Yikui Gao Linglin Zhou Jie Wang Zhong Lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China College of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

The development of the Internet of Things(IoT)and artificial intelligence has accompanied the evolution of energy demand and structure in the new era,and the power sources for billions of distributed electronics and sensors have aroused worldwide *** an alternative energy harvesting technology,triboelectric nanogenerators(TENGs)have received remarkable attention and have shown attractive potential applications for use in micro/nano power sources,self-powered sensors,highvoltage power sources,and blue energy due to their advantages of small size,light weight,flexibility,low cost,and high efficiency at low *** this review,we discuss high-performance TENGs from the perspectives of triboelectric charge density,output voltage,energy density,and corresponding quantification *** these topics,the limitations,optimization methods and techniques,and potential directions to challenge these limits are comprehensively discussed and ***,we discuss the emerging challenges,strategies,and opportunities for research and development of highperformance TENGs.

关键词： high-performance triboelectric nanogenerator(TENG) charge density voltage energy density average power density

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毛细驱动诱发的尾矿强度劣化演化规律及机制

安全与环境学报 2024年第2期24卷 503-510页

作者：刘迪李泽宇卢才武杨辉张泽家顾清华连民杰西安建筑科技大学资源工程学院西安710055 西安市智慧工业感知计算与决策重点实验室西安710055 西安本末安全环保技术服务有限公司西安710100 中钢集团矿业开发有限公司北京100080

为了研究毛细作用对尾矿坝工程性质的影响规律及机制,以陕西某铜矿尾矿为研究对象,通过直剪试验对自然含水状态下、毛细饱和状态下、重力饱和状态下堆积坝外坡和沉积滩面不同距离处的尾矿进行力学性质测试。结果表明:尾矿黏聚力随粒径... 详细信息

为了研究毛细作用对尾矿坝工程性质的影响规律及机制,以陕西某铜矿尾矿为研究对象,通过直剪试验对自然含水状态下、毛细饱和状态下、重力饱和状态下堆积坝外坡和沉积滩面不同距离处的尾矿进行力学性质测试。结果表明:尾矿黏聚力随粒径减小逐渐增大,内摩擦角随粒径减小逐渐减小,二者共同作用影响其抗剪强度;随含水率的增大,尾矿强度逐渐下降;浸润线以上毛细饱和带中尾矿含水率与浸润线以下尾矿含水率相等;基于以上研究结果,引入毛细饱和带概念,提出了基于毛细作用影响的尾矿坝真实浸润线的概念与计算方法,修正了浸润线高度计算公式。

关键词：安全工程尾矿库安全毛细作用抗剪强度浸润线