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Applied Geophysics 2022年第4期19卷 485-502,603页

作者： Pang meng-Qiang Ba Jing Wu Chun-Fang Carcione José maria müller Tobias School of Earth Science and Engineering Hohai UniversityNanjingu211000China Bochum University of Applied Sciences D-44801 BochumGermany Shanghai Technical Institute of Electronics and Information Shanghai201411China National Institute of Oceanography and Applied Geophysics(OGS) SgonicoTrieste 34010

In recent years,the Yanchang shale-oil formations of the Ordos Basin are rich in reserves with complex lithology and structure characteristics,low porosity and low permeability,and weak anomalies for oil and water discriminations,have been the key targets of unconventional oil/gas resource exploration and development in the relevant *** joint acoustic-electrical(AE)properties can be used to interpret reservoir lithology,mineralogy,pore structure,and fluid *** conduct tests of thin section analysis,X-ray diff raction,and ultrasonic and electrical experiments at diff erent pressures and saturation degrees,cores from the shale-oil formations in the Q area of the basin are *** variations in AE properties with respect to clay content,porosity,pressure(microfracture),and saturation are *** experimental results indicate that the rock physics behaviors of sandstones with diff erent clay contents vary *** AE properties of clean sandstones are basically dependent on the microfractures(pressure),while for muddy sandstones,the clay content is an important factor affecting the *** target reservoir consists of interbedded sandstone and shale *** AE equivalent medium equations and the Gurevich theory are applied to establish the joint models for the diff erent lithologies and simulate the variations in AE properties with respect to fluid type,pore structure,and mineral *** three-dimensional joint templates of clean and muddy sandstones,as well as shale,are developed based on the elastic and electrical attributes and then calibrated using the experimental and well-log *** reservoir properties are estimated with the templates and validated by the log *** results indicate that the joint templates based on lithology characteristics can eff ectively characterize the properties of interbedded sandstone and shale ***,the combined application of AE data provides more beneficial informatio

关键词： shale-oil formations acoustic-electrical(AE)properties interbedded layers clay content pore structure rock physics model

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甜菜种子中线粒体的纯化研究

中山大学学报（自然科学版） 2000年第3期39卷 78-81页

作者：宋松泉 Kenneth m.FREDLUND Ian m.mφller 中山大学生命科学学院广东广州510275 Department of Seed Physiology Novartis Seeds AB Department of Plant Physiology Lund University

吸胀 2 4h的甜菜 (BetavulgarisL cv Loke)种子线粒体通过差速离心和修改的Percoll梯度 (上部为 0 3mol/L甘露醇 ,下部为 0 3mol/L蔗糖 )被纯化 .线粒体位于Percoll梯度的上部 ,大约 30～ 35mL处 .细胞色素C氧化酶 (线粒体的标记酶 )... 详细信息

吸胀 2 4h的甜菜 (BetavulgarisL cv Loke)种子线粒体通过差速离心和修改的Percoll梯度 (上部为 0 3mol/L甘露醇 ,下部为 0 3mol/L蔗糖 )被纯化 .线粒体位于Percoll梯度的上部 ,大约 30～ 35mL处 .细胞色素C氧化酶 (线粒体的标记酶 )活性、苹果酸脱氢酶活性和蛋白质含量主要分布在此部位 .

关键词：线粒体纯化 Percoll梯度甜菜种子

A patchy-saturated rock physics model for tight sandstone based on microscopic pore structures

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Applied Geophysics 2022年第2期19卷 147-160,306页

作者： Wu Chun-Fang Ba Jing Carcione José m. müller Tobias m. Zhang Lin School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China National Institute of Oceanography and Applied Geophysics(OGS) Trieste 34010Italy

The wave-induced local fluid flow mechanism is relevant to the complex heterogeneity of pore structures in *** analysis of the local fluid flow mechanism is useful for accurately describing the wave propagation characteristics in reservoir *** the exploration and production of hydrocarbon reservoirs,the real stratum.may be partially saturated with a multi-phase fluid mixture in ***,it is of great significance to investigate the wave velocity dispersion and attenuation features in relation to pore structures and *** this work,the characteristics of fabric microstructures are obtained on the basis of pressure dependency of dry rock moduli using the effective medium theory.A novel anelasticity theoretical model for the wave propagation in a partially-saturated medium is presented by combining the extended Gurevich squirt-flow model and White patchysaturation *** simulations are used to analyze wave propagation characteristics that depend on water saturation,external patchy diameter,and *** consider a tight sandstone from the Qingyang area of the Ordos Basin in west China and perform ultrasonic measurements under partial saturation states and different confining pressures,where the basic properties of the rock are obtained at the full gas *** comparison of experimental data and theoretical modeling results shows a fairly good agreement,indicating that the new theory is effective.

关键词： Pore structure patchy saturation state squirt-flow effect wave velocity dispersion and attenuation

Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： Jens müller Sebastian Leonow Johannes Schulz Christian Hansen martin monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

An explainable AI framework for robust and transparent data-driven wind turbine power curve models

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Energy and AI 2024年第1期15卷 312-327页

作者： Simon Letzgus Klaus-Robert müller machine Learning Group Technische Universitβe BerlinStraβe des 17.Juni 135Berlin10623Germany Berlin Institute for the Foundations of Learning and Data Berlin10587Germany Department of Artificial Intelligence Korea UniversitySeoul136-713South Korea max Planck Institute for Informatics Saarbrücken66123Germany

In recent years,increasingly complex machine learning methods have become state-of-the-art in modelling wind turbine power curves based on operational *** these methods often exhibit superior performance on test sets,they face criticism due to a perceived lack of transparency and concerns about their robustness in dynamic,non-stationary environments encountered by wind *** this work,we address these issues and present a framework that leverages explainable artificial intelligence methods to gain systematic insights into data-driven power curve *** its core,we propose a metric to quantify how well a learned model strategy aligns with the underlying physical principles of the *** novel tool enables model validation beyond the conventional error metrics in an automated *** demonstrate,for instance,its capacity as an indicator for model generalization even when limited data is ***,it facilitates understanding how decisions made during the machine learning development process,such as data selection,pre-processing,or training parameters,affect learned *** a result,we obtain physically more reasonable models,a prerequisite not only for robustness but also for meaningful insights into turbine operation by domain *** latter,we illustrate in the context of wind turbine performance *** summary,the framework aims to guide researchers and practitioners alike toward a more informed selection and utilization of data-driven wind turbine power curve models.

关键词： Explainable AI(XAI) machine learning Wind energy Wind turbine power curve SCADA Condition monitoring

Nano-and micro-patterned Biomaterials

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复旦学报（自然科学版） 2007年第5期46卷 706-页

作者： m.C.Lensen m.Diez V.A.Schulte P.mela m.mller DWI e.V.and Institute of Technical and macromolecular Chemistry RWTH AachenGermany

1 Results Our objective is two fold: we (ⅰ) aim at the development of novel patterning methodologies in order to (ⅱ) achieve control over the positioning and alignment of living *** patterning of the biointerfaces is carried out both at the micro-and nanometer scale and involve (bio)chemical as well as topographic *** former are relatively easily obtained by patterning techniques adapted from (conventional) soft lithography,*** means of micro-contact printing (μ-CP).The topographic pat...

关键词： soft lithography hydrogels nanoimprinting UV-curing cell adhesion

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彩色电视屏用光敏磷光体粉浆的研磨条件

发光学报 1975年第3期 7-9页

作者： m.mller 周国华 AEG电话公司西德

美国电化学学会第145次会议文章摘要中,有53篇和发光材料、显示器件有关。我们从中选译了一部份,陆续刊登以供参考。这次刊出的是和彩色电视有关的文章摘要,参考资料目录一律从略。

关键词：磷光体粉浆扫描电子显微照片润湿能力

Analyzing voting power in decentralized governance:Who controls DAOs?

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Blockchain(Research and Applications) 2024年第3期5卷 123-129页

作者： Robin Fritsch marino müller Roger Wattenhofer ETH Zurich 8092ZurichSwitzerland

We empirically study the state of three prominent DAO governance systems on the Ethereum blockchain:Compound,Uniswap and Ethereum name service(ENS).In particular,we examine how the voting power is distributed in these *** a comprehensive dataset of all governance token holders,delegates,propos-als,and votes,we analyze who holds the voting power and how this power is being used to influence governance *** we reveal that the majority of voting power is concentrated in the hands of a small number of addresses,we rarely observe these powerful entities overturning a vote by choosing a different outcome than that of the overall community and less influential voters.

关键词： Decentralized autonomous organization DAO governance Liquid democracy Blockchain

New Amphiphilic Amino Acid Derivatives for Efficient DNA Transfection in Vitro

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Advances in Chemical Engineering and Science 2017年第2期7卷 191-205页

作者： Lucía C.Pena maría F.Argaraná maría m.De Zan Antonella Giorello Sebastián Antuna Claudio C.Prieto Carolina m.I.Veaute Diana m.müller LAQUImAP Dto.Química OrgánicaUniversidad Nacional del LitoralSanta FeArgentina Cát.microbiología General Universidad Nacional del LitoralSanta FeArgentina Laoratorio de Control de medicamentos Universidad Nacional del LitoralSanta FeArgentina Instituto de Investigaciones en Catálisis y Petroquímica Universidad Nacional del LitoralSanta FeArgentina Laboratorio de Cultivos Celulares Universidad Nacional del LitoralSanta FeArgentina Laboratorio de Inmunología Básica Universidad Nacional del LitoralSanta FeArgentina

Nucleic acids-based therapies have recently developed as next-generation agents for treating and preventing viral infection, cancer, and genetic disorders, but their use is still limited due to its relatively poor delivery into targeted cells. We designed and synthesized new amphiphilic amino acid derivatives (cysteine-based) of low molecular weight, formed by the same pentapeptide (AG2: WWCOO) N-acylated, with different hydrophobic chains containing from 12 to 18 carbons, named AG2-Cn (N), which dimerize by oxidation in the presence of pLenti-CmV-GFP Puro plasmid (P) in the respective gemini. We determined transfection efficiency, critical micelle concentration, particle size, ζ-potential and cytotoxicity for the derivatives obtained. We found that all the synthesized compounds were active for DNA delivery and had greater ability to transfect CHO-K1 cells. In particular, AG2-C18 is a promising carrier for gene delivery because it showed no cytotoxicity and its activity was greater than or equal to the commercial actives currently used.

关键词： Amphiphile N-Acylated Cysteine Gemini Ornithine Transfection