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Machine Learning and Data fusion Approach for Elastic Rock Properties Estimation and fracturability Evaluation

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Energy and AI 2024年第2期16卷 1-13页

作者： Yiwen Gong Ilham El-monier Mohamed Mehana The Ohio State University SimTech LLC Los Alamos National Laboratory

Accurate rock elastic property determination is vital for effective hydraulic fracturing,particularly Young’s modulus due to its link to rock *** study integrates interdisciplinary data for better predictions of elastic modulus,combining data mining,experiments,and calibrated *** used the microstructural insights extracted from rock images for geomechanical facies ***,the petrophysical data and well logs were correlated with shear wave velocity(Vs)and Young’s *** developed a machine-learning workflow to predict Young’s modulus and assess rock fracturability,considering mineral composition,geomechanics,and *** findings indicate that artificial neural networks effectively predict Young’s modulus,while K-Means clustering and hierarchical support vector machines excel in identifying rock and geomechanical *** Microscale thin section analysis in conj.nction with fracture modeling enhances our understanding of fracture geometries and facilitates fracturability ***,fracturability is controlled by specific geomechanical facies during initiation and propagation and influenced by continuity of geomechanical facies in small depth *** conclusion,this study demonstrates data mining and machine learning potential for predicting rock properties and assessing fracturability,aiding hydraulic fracturing design optimization through diverse data and advanced methods.

关键词： Young’s modulus prediction fracability evaluation landing point selection rock mechanics machine learning

Interfacial effects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. j. Sabina A.B.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the effects of dispersion of Bloch-floquet waves. A particular attention is given to structures containing interfaces between dissimilar media and localization of the electrical fields near such interfaces.

关键词： Piezoelectric periodic composites Interfaces Dispersion of Bloch-floquet waves

Oxidation and Coatings for Power Generation： New Super Ultra Critical Steam Turbines

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中国腐蚀与防护学报 2009年第4期29卷 318-319页

作者： f. j. PEREZ Grupo de Investigacion de Ingenieria de Superficies y Materiales Nanoestructurados U. C. M. N°910627 facultad de Ciencias Quimicas Universidad Complutense de Madrid. 28040 Madrid Spain

The steels with chromium contents between 9%and 12%wt are used for power plants with advanced steam oxidation *** present good creep properties as 9%Cr steels and good oxidation resistance,at the temperatures range between 500℃～600℃.In the last years numerous investigation in development of coatings has been realized with the aim the protected them against the oxidation in order to allow operation of steam turbines at 650℃.In this study,Al-Hf protective coatings were deposited by CVD-fBR on ferritic steel HCM-12A followed by a diffusion heat treatment,have shown to be protective at 650℃under steam for at least 3000 hours of laboratory steam exposure under atmospheric *** and composition of coatings were characterized by different techniques, such as scanning electron microscopy(SEM),electron probe microanalysis,and X-ray diffraction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermogravimetric measurements (TG) during the initial stages oxidation of the P92 ferritic steel without and of Al and Al/Si coating by chemical vapour deposition in fluidized bed reactors(CVD-fBR) at 650℃in Ar+20%H_2O for 150 h were *** order to go forward to coatings design the Thermocalc code is used as base for the MSdata. TG-MS experiments were conducted in a closed steam loop in order to obtain information about the oxyhydroxides formation as reaction between coatings and *** those results the role of the different coating element could be established and optimized for the coating *** oxidation mechanism based on the TG-MS results is *** morphology/composition and structure of the oxidized samples were also studied using SEM/EDS and XRD techniques.

关键词：氧化金属腐蚀防护

Topsoil as Affected by Dung Deposition Under Resting Places of Red Howler Monkey (Alouatta seniculus)

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Pedosphere 2008年第6期18卷 691-698页

作者： S. POUVELLE f. fEER j. f. PONGE Musum National d'Histoire Naturelle CNRS UMR 7179 4 avenue du Petit-Chateau

The short-term influence of dung deposition and the further redistribution of dung by dung beetles were studied under a resting place of the red howler monkey （Alouatta seniculus） living in tropical ralnforests of South America. Monkey dung was experimentally clumped on the field in a place used by troops of howler monkeys for resting in the Nouragues Reserve Station, french Guiana. Dung-treated plots were sampled serially over three weeks and compared with controls located in their immediate vicinity. The composition of the soil matrix （top 10 cm） was studied in successive microlayers using an optical method. Under the influence of dung beetle activity, the topsoil became more homogeneous by losing its litter, its content in earthworm faeces increased in the course of time, and surface mineral deposits were penetrated by roots. The results were interpreted in the light of present knowledge on the effects of soil animal activity on plant growth and survival of seedlings.

关键词： dung beetle activity earthworm faeces roots tropical ralnforests

Light metal compound casting

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Science China(Technological Sciences) 2009年第1期52卷 46-51页

作者： Konrad j. M. PAPIS j.erg f. LOEffLER Peter j. UGGOWITZER ETH Zurich Laboratory of Metal Physics and Technology Wolfgang-Pauli-Str. 10

‘Compound casting’simplifies j.ining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as j.int structures of spaceframe constructions in transport industry. In this proj.ct, ‘compound casting’ of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu- ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the j.ining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and Al12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protective coating to the substrate.

关键词： compound casting aluminium alloys magnesium alloys interface structure

Shale characteristics impact on Nuclear Magnetic Resonance (NMR) fluid typing methods and correlations

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Petroleum 2016年第2期2卷 138-147页

作者： Mohamed Mehana Ilham El-monier University of Oklahoma Suez UniversityUSA University of Oklahoma USA

The development of shale reservoirs has brought a paradigm shift in the worldwide energy *** entails developing robust techniques to properly evaluate and unlock the potential of those *** application of Nuclear Magnetic Resonance techniques in fluid typing and properties estimation is well-developed in conventional ***,Shale reservoirs characteristics like pore size,organic matter,clay content,wettability,adsorption,and mineralogy would limit the applicability of the used interpretation methods and *** of these limitations include the inapplicability of the controlling equations that were derived assuming fast relaxation regime,the overlap of different fluids peaks and the lack of robust correlation to estimate fluid properties in *** study presents a state-of-the-art review of the main contributions presented on fluid typing methods and correlations in both experimental and theoretical *** study involves Dual Tw,Dual Te,and doping agent's application,T1-T2,D-T2 and T2sec vs.T1/T2 *** addition,fluid properties estimation such as density,viscosity and the gas-oil ratio is *** study investigates the applicability of these methods along with a study of the current fluid properties correlations and their ***,it recommends the appropriate method and correlation which are capable of tackling shale heterogeneity.

关键词： Shale fluid typing fluid properties Heterogeneity Nuclear Magnetic Resonance

Magnetic Behaviour of Sm2Co7/fe/Sm2 Co7, Nanocomposite Trilayers with Cr and Ti Additions

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Chinese Physics Letters 2009年第3期26卷 255-257页

作者： f. Shahzad S. A. Siddiqi j. Zhou Advaaced Light Source Berkeley Lab University of California Berkeley CA 94720 USA Centre for Solid State Physics University of the Punjab Lahore-54590 Pakistan Department of Physics University of California Berkeley California 94720 USA

Trilayered Sm2Co7/fe/Sm2Co7 spring exchange magnets are fabricated by dc magnetron sputtering on MgO substrates. Very thin layers （0.3-0.7 nm） of Cr and Ti are added at the interfaces of the two magnetic phases. The thickness of StucCo7 is kept at 20nm and fe at 6nm while the thickness of Cr and Ti are varied as 0.3, 0.5, and 0.7nm. The base pressure of sputtering chamber is kept below 10^-7 Torr and Ar pressure at 3-8m Torr. The samples are characterized by x-ray diffraction （XRD） and SQUID magnetometer. We report improvement in exchange coupling of nonacomposite magnets by addition of thin layers of Cr at interfaces.

关键词： MAGNETIC materials MAGNETIC properties COMPOSITE materials LAYER structure (Solids) MICROfABRICATION NANOSTRUCTURED materials ADDITION reactions SAMARIUM

fabrication and Characterization of SmCo5/fe65Co35 and SmCo5/fe Composite Spring Exchange Magnets

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Chinese Physics Letters 2008年第7期25卷 2642-2644页

作者： f. Shahzad S. A. Siddiqi j. Zhou Centre for Solid State Physics University of the Punjab Lahore-54590 Pakistan Department of Physics University of California Berkeley California-P4720 USA

SmCo5/fe65Co35 and SmCo5/fe spring exchange magnets are fabricated by dc magnetron sputtering on MgO substrates and 100-nm-thick Si3N4 membranes, respectively. The base pressure of sputtering chamber is kept below 10^-7 Tort, and Ar pressure is 3 to 8mTorr. The samples are characterized by an x-ray diffractometer, a superconducting quantum interference magnetometer, and high resolution magnetic soft x-ray microscopy. We obtain the complete exchange coupling and single phase behaviour of composite magnets. The （BH）max value achieved is 28.8 MGOe.

关键词： the power-law exponents precipitation durative abrupt precipitation change

UV/visible spectroscopic analysis of CO^(3+) and CO^(2+) during the dissolution of cobalt from mixed Co-Cu oxidized ores

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International j.urnal of Minerals,Metallurgy and Materials 2011年第3期18卷 260-269页

作者： j. Ndalamo A.f. Mulaba-Bafubiandi B.B. Mamba Department of Chemical Technology University of Johannesburg Department of Extraction Metallurgy University of Johannesburg

The leaching of cobalt from four-mixed Co-Cu oxidized ores containing cobalt at levels ranging from 0.5wt% to 34wt% was studied and the results has been reported. Conventional dissolution of these oxidized Co-Cu ores with diluted H2SO4 and SO2 as a reducing agent resulted in a substantial improvement in the solution based recovery of cobalt. UV/visible spectroscopic analysis of the leached solu-tions indicated that the increased cobalt content in the solution was a result of flushing the acidified cobalt leaching solution with SO2. fur-thermore, UV/visible spectroscopy confirmed that as SO2 was flushed into the acidified leaching solution, Co3＋ bearing minerals were re-duced to the readily soluble Co2＋ bearing minerals, and this resulted in the increase of total cobalt in the collected solution. The mechanism of the reduction of Co3＋ to Co2＋ bearing minerals when SO2 is flushed during the leaching of mixed Co-Cu oxidized ores, including the stability trends of Co3＋, Co2＋, and Cu2＋ complexes, as shown by their UV/visible spectra, are also discussed.

关键词： cobalt metallurgy dissolution leaching reaction kinetics spectroscopic analysis