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含硫气藏元素硫沉积及防治对策研究

钻采工艺 2005年第6期28卷 86-89,92页

作者：欧成华胡晓东万红心西南石油学院石油工程测井实验室西南油气田公司川东北气矿塔里木油田公司西气东输项目部

通过对西方发达国家在含硫气藏元素硫沉积及防治对策研究方面所获成果的系统分析,获得以下认识:元素硫沉积将严重影响含硫气井动态,甚至造成关井停产,具有巨大危害;当流体组分中硫化氢含量较高、凝析物(C5+)含量较低,井底压力温度较高,... 详细信息

通过对西方发达国家在含硫气藏元素硫沉积及防治对策研究方面所获成果的系统分析,获得以下认识:元素硫沉积将严重影响含硫气井动态,甚至造成关井停产,具有巨大危害;当流体组分中硫化氢含量较高、凝析物(C5+)含量较低,井底压力温度较高,或从井底到井口具有较大的温度压力变化时,近井地带和井筒节流部件附近极易发生硫沉积;目前主要采取向井中加入溶硫剂等事后措施防治硫沉积,而有关预防元素硫沉积危害的技术还有待进一步研究。

关键词：含硫气藏元素硫沉积防治对策

The low Mach number limit of non-isentropic magnetohydrodynamic equations with large temperature variations in bounded domains

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Science China Mathematics 2024年第4期67卷 787-818页

作者： Min Liang Yaobin ou School of Mathematics Renmin University of ChinaBeijing 100872China

This paper verifies the low Mach number limit of the non-isentropic compressible magnetohydrodynamic(MHD)equations with or without the magnetic diffusion in a three-dimensional bounded domain when the temperature variation is large but *** uniform estimates of strong solutions are established in a short time interval independent of the Mach number,provided that the slip boundary condition for the velocity and the Neumann boundary condition for the temperature are imposed and the initial data is well-prepared.

关键词： low Mach number limit non-isentropic compressible magnetohydrodynamic equations large temperature variations bounded domains

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页岩纳米孔隙表面分形特征及其影响因素

西南石油大学学报（自然科学版） 2017年第6期39卷 85-91页

作者：孙雷高玉琼潘毅欧成华 "油气藏地质及开发工程"国家重点实验室.西南石油大学四川成都610500

明确页岩纳米孔隙表面分形特征有助于深化对页岩吸附机理与吸附模型的认识。以五峰组/龙马溪组、延长组页岩为研究对象,基于氮气吸附法孔隙结构参数,计算了页岩纳米孔隙表面分形维数,并与泥岩、致密砂岩分形维数对比,揭示了有机质、黏... 详细信息

明确页岩纳米孔隙表面分形特征有助于深化对页岩吸附机理与吸附模型的认识。以五峰组/龙马溪组、延长组页岩为研究对象,基于氮气吸附法孔隙结构参数,计算了页岩纳米孔隙表面分形维数,并与泥岩、致密砂岩分形维数对比,揭示了有机质、黏土矿物等对孔隙表面分形特征的影响。研究表明,五峰组/龙马溪组页岩纳米孔隙表面分维值为2.7~2.9,延长组页岩为2.3~2.7,其分维值取决于10 nm以下孔隙累计表面积大小;页岩分维值与有机质成熟演化阶段正相关,而与有机质含量关系复杂;有机质孔与黏土矿物晶间孔表面均具有明显的分形特征,该孔隙发育是页岩具有表面分形特征的根本性原因,但前者的分维值显著大于后者有机质与黏土矿物表面呈现高度粗糙性,严重偏离光滑平整特性,因此,甲烷在页岩纳米孔内的吸附属于典型的非均匀固体上的吸附。

关键词：分形表面纳米孔页岩有机质黏土矿物

High-throughput screening of single-atom catalysts confined in monolayer black phosphorus for efficient nitrogen reduction reaction

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Nano Research 2024年第4期17卷 2360-2367页

作者： Xiao-Yan Li Manyi Duan Pengfei ou Department of Electrical and Computer Engineering University of TorontoTorontoOntario M5S 1A4Canada School of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610101China Department of Chemistry Northwestern UniversityEvanstonIL 60208USA

The discovery of metal-nitrogen centers as the active sites for electrolysis has aroused significant interest in utilizing single-atom catalysts for nitrogen reduction reaction(NRR).Properly designed nanostructured catalysts that strongly interact with nitrogen molecules(N_(2))can promote adsorption and activation,thereby resulting in efficient catalysts with high stability,activity,and *** this study,using density functional theory calculations,we selected monolayer black phosphorus(BP)as the substrate and screened a series of single-atom transition metals confined in tri-coordinated and tetra-coordinated active centers(without and with N dopants)to electro-catalyze *** a result,we have identified two promising candidates(Hf_(1)-N_(1)P_(2)-1 and Tc_(1)-N_(4)),which exhibit not only low overpotentials of 0.56 and 0.49 V but also high thermodynamic and electrochemical stability,as well as good selectivity towards NRR over the competing hydrogen evolution *** also demonstrate the ability of Hf_(1)-N_(1)P_(2)-1 and Tc_(1)-N_(4) to activate and hydrogenate N_(2) by donating electrons and regulating charge *** study not only predicts new BP-based promising catalysts but also provides guidance for the rational design of high-performance NRR electrocatalysts under ambient conditions.

关键词： N_(2) electroreduction reaction single-atom catalysts black phosphorus density functional theory high-throughput calculations

Block Basis for Modular Coinvariants of Pseudo-Reflection Groups

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Algebra Colloquium 2024年第1期31卷 41-48页

作者： Ke ou School of Statistics and Mathematics Yunnan University of Finance and Economics Kunming 650221China

We investigate the block basis for modular coinvariants of finite pseudo-reflection *** are particularly interested in the case of a subgroup G of the parabolic subgroups of GLn(q)which generalizes the Weyl groups of ... 详细信息

关键词： modular invariant theory pseudo-reflection group block basis coinvariant

Development of a convolutional neural network based geomechanical upscaling technique for heterogeneous geological reservoir

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2111-2125页

作者： Zhiwei Ma Xiaoyan ou Bo Zhang Earth and Environmental Sciences Division Los Alamos National LaboratoryLos AlamosUSA Civil and Environmental Engineering University of AlbertaEdmontonCanada

Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological ***,a robust and efficient geomechanical upscaling technique for heterogeneous geological reservoirs is lacking to advance the applications of three-dimensional(3D)reservoir-scale geomechanical simulation considering detailed geological ***,we develop convolutional neural network(CNN)proxies that reproduce the anisotropic nonlinear geomechanical response caused by lithological heterogeneity,and compute upscaled geomechanical properties from CNN *** CNN proxies are trained using a large dataset of randomly generated spatially correlated sand-shale realizations as inputs and simulation results of their macroscopic geomechanical response as *** trained CNN models can provide the upscaled shear strength(R^(2)>0.949),stress-strain behavior(R^(2)>0.925),and volumetric strain changes(R^(2)>0.958)that highly agree with the numerical simulation results while saving over two orders of magnitude of computational *** is a major advantage in computing the upscaled geomechanical properties directly from geological realizations without the need to perform local numerical simulations to obtain the geomechanical *** proposed CNN proxybased upscaling technique has the ability to(1)bridge the gap between the fine-scale geocellular models considering geological uncertainties and computationally efficient geomechanical models used to assess the geomechanical risks of large-scale subsurface development,and(2)improve the efficiency of numerical upscaling techniques that rely on local numerical simulations,leading to significantly increased computational time for uncertainty quantification using numerous geological realizations.

关键词： Upscaling Lithological heterogeneity Convolutional neural network(CNN) Anisotropic shear strength Nonlinear stressestrain behavior

Pixel-level crack segmentation of tunnel lining segments based on an encoder–decoder network

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 681-698页

作者： Shaokang Hou Zhigang ou Yuequn HUANG Yaoru LIU State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China China Renewable Energy Engineering Institute Beijing 100120China State Key Laboratory of Stimulation and Regulation of Water Cycles in River Basins China Institute of Water Resources and Hydropower ResearchBeijing 100038China Hunan Provincial Water Resources Development&Investment Co. Ltd.Changsha 410007China

Regular detection and repair for lining cracks are necessary to guarantee the safety and stability of *** development of computer vision has greatly promoted structural health *** study proposes a novel encoder–decoder structure,CrackRecNet,for semantic segmentation of lining segment cracks by integrating improved VGG-19 into the U-Net *** image acquisition equipment is designed based on a camera,3-dimensional printing(3DP)bracket and two laser rangefinders.A tunnel concrete structure crack(TCSC)image data set,containing images collected from a double-shield tunnel boring machines(TBM)tunnel in China,was *** data preprocessing operations,such as brightness adjustment,pixel resolution adjustment,flipping,splitting and annotation,2880 image samples with pixel resolution of 448×448 were *** model was implemented by Pytorch in PyCharm processed with 4 NVIDIA TITAN V *** the experiments,the proposed CrackRecNet showed better prediction performance than U-Net,TernausNet,and *** paper also discusses GPU parallel acceleration effect and the crack maximum width quantification.

关键词： tunnel lining segment crack detection semantic segmentation convolutional neural network encoder-decoder structure

Entangled photons enabled ultrafast stimulated Raman spectroscopy for molecular dynamics

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Light(Science & Applications) 2024年第8期13卷 1615-1622页

作者： Jiahao Joel Fan Zhe-Yu ou Zhedong Zhang Department of Physics City University of Hong KongKowloonHong Kong SARChina City University of Hong Kong Shenzhen Research InstituteShenzhenGuangdongChina

Quantum entanglement has emerged as a great resource for studying the interactions between molecules and *** propose a new scheme of stimulated Raman scattering with entangled photons.A quantum ultrafast Raman spectroscopy is developed for condensed-phase molecules,to monitor the exciton populations and *** results are obtained,showing an entanglement-enabled time-frequency scale not attainable by classical *** Raman signal presents an unprecedented selectivity of molecular correlation functions,as a result of the Hong-ou-Mandel *** work suggests a new paradigm of using an unconventional interferometer as part of spectroscopy,with the potential to unveil advanced information about complex materials.

关键词： materials spectroscopy selectivity

Performance Prediction Based Workload Scheduling in Co-Located Cluster

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2043-2067页

作者： Dongyang ou Yongjian Ren Congfeng Jiang School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou310018China

Cloud service providers generally co-locate online services and batch jobs onto the same computer cluster,where the resources can be pooled in order to maximize data center resource *** to resource competition between batch jobs and online services,co-location frequently impairs the performance of online *** study presents a quality of service(QoS)prediction-based schedulingmodel(QPSM)for *** performance prediction of QPSM consists of two parts:the prediction of an online service’s QoS anomaly based on XGBoost and the prediction of the completion time of an offline batch job based on ***-line service QoS anomaly prediction is used to evaluate the influence of batch jobmix on on-line service performance,and batch job completion time prediction is utilized to reduce the total waiting time of batch *** the same number of batch jobs are scheduled in experiments using typical test sets such as CloudSuite,the scheduling time required by QPSM is reduced by about 6 h on average compared with the first-come,first-served strategy and by about 11 h compared with the random scheduling *** with the non-co-located situation,QPSM can improve CPU resource utilization by 12.15% and memory resource utilization by 5.7% on *** show that the QPSM scheduling strategy proposed in this study can effectively guarantee the quality of online services and further improve cluster resource utilization.

关键词： Co-located cluster workload scheduling online service batch jobs data center