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Three-dimensional analysis of a faulted CO2 reservoir using an Eshelby-Mori-Tanaka approach to rock elastic properties and fault permeability

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Journal of rock Mechanics and Geotechnical Engineering 2016年第6期8卷 828-845页

作者： ba Nghiep Nguyen Zhangshuan hou George V.Last Diana h.bacon Pacific Northwest National Laboratory RichlandWAUSA

This work develops a three-dimensional(3D) multiscale model to analyze a complex carbon dioxide(CO_2) faulted reservoir that includes some key geologic features of the San Andreas and nearby faults southwest of the Kimberlina *** model uses the STOMP-CO2 code for flow modeling that is coupled to the AbaQUS~ finite element package for geomechanical analysis.A 3D AbaQUS~ finite element model is developed that contains a large number of 3D solid elements with two nearly parallel faults whose damage zones and cores are discretized using the same continuum *** zones with different mineral compositions are considered:shale,sandstone,fault damaged sandstone,fault damaged shale,and fault ***' elastic properties that govern their poroelastic behavior are modeled by an Eshelby-Mori-Tanaka approach(EMTA).which can account for up to 15 mineral *** permeability of fault damage zones affected by crack density and orientations is also predicted by an EMTA formulation.A STOMP-CO2 grid that exactly maps the AbaQUS~ finite element model is built for coupled hydromechanical *** of the reservoir assuming three different crack pattern situations(including crack volume fraction and orientation) for the fault damage zones are performed to predict the potential leakage of CO_2 due to cracks that enhance the permeability of the fault damage *** results illustrate the important effect of the crack orientation on fault permeability that can lead to substantial leakage along the fault attained by the expansion of the CO_2 *** hydraulic fracture and tendency for the faults to slip are also examined and discussed in terms of stress distributions and geomechanical properties.

关键词： Carbon dioxide(CO_2) reservoir Geomechanical modeling Mineralogy homogenization Fault Leakage Slip Elastic properties

Influence of Solid Fraction on Gravity Segregation of Sn in A1-20Sn Alloy Casting

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Journal of Materials Science & Technology 2000年第6期16卷 577-580页

作者： Zhang P. Du Y.h. Zeng D.B. Cui J.Z. ba L.M. Dep. of Mechanical Eng. Tsinghua Univ. Beijing 100084 China

The influence of solid fraction of Al-20Sn alloy mushy on gravity segregation of Sn in casting was studied . The relationship between solid fraction and the temperature of alloy mushy and that between solid fraction of alloy mushy and size of Sn particle in ingot were determined. The results show that the relationship between solid fraction and the temperature of alloy mushy was fs=1683-4.86t+0.003 5t2. The extent of gravity segregation of Sn in casting reduced gradually with the increase of solid fraction of alloy mushy. When solid fraction of alloy mushy was larger than 40%, the gravity segregation of Sn in casting could be removed basically, and the relationship between solid fraction of alloy mushy and size of Sn particle in ingot was s=-0.64fs+70.8.

关键词： Metal casting

Zeolite usage as source of silica to produce cordierite in MgO–Al_2O_3–SiO_2 system

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Journal of Advanced Ceramics 2018年第4期7卷 370-379页

作者： Tu?ba Tun? PArLAK A.?ükran DEMIrKIrAN Department of Metallurgical and Materials Engineering Faculty of EngineeringSakarya UniversityEsentepe Campus

In this study, natural zeolite was used as source of silica to produce cordierite. MgO and Al_2O_3 were added to zeolite to obtain the cordierite stoichiometry. Mixture of these raw materials was mechanically activated for different durations. The mechanically activated powder mixture was characterized using XrD, DSC, SEM, specific surface area, and particle size analyzer. The pycnometer method was used to measure the densities of mechanically activated powder mixtures. Mechanically activated for 60 min powder mixture was sintered at 1150–1350 ℃ for 1 h. The sintering behavior of the samples was determined by measuring the linear shrinkage, density, and apparent porosity. The phases in the sintered samples were identified by XrD. Cordierite and spinel phases were detected for sintered at a temperature higher than 1150 ℃ but corundum accompanied to cordierite and spinel at 1150 ℃. The microstructure of the samples was examined using both SEM and AFM. The sintering behavior and microstructural properties of the samples changed with an increase in the sintering temperature. As the apparent porosity increased with increasing sintering temperature, linear shrinkage and density values decreased. Density values were determined as 2.31–2.69 g/cm^3 depending on the temperature. The grains coarsened at higher temperature and the average grain size depending on the temperature was 1.34–1.96 μm. From the results optimum sintering temperature was determined as 1250 ℃. Dense material was produced at a temperature as low as 1250 ℃ using zeolite as raw material.

关键词： mechanical activation sintering zeolite cordierite

Multiplicity and Uniqueness of Positive Solutions for Nonhomogeneous Semilinear Elliptic Equation with Critical Exponent

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Acta Mathematicae Applicatae Sinica 2016年第1期32卷 81-94页

作者： Na ba Yan-yan WANG Lie ZhENG School of Science Hubei University of Technology Department of Mathematics Zhoukou Normal University

In this paper,we consider the following problem {-Δu（x）＋u（x）=λ（u^p（x）＋h（x））,x∈r^N,u（x）∈h^1（r^N）,u（x）〉0,x∈r^N,（＊）where λ 〉 0 is a parameter,p =（N＋2）/（N—2）.We will prove that there exists a positive constant 0 〈 A＊〈＋00such that（＊） has a minimal positive solution for λ∈（0,λ＊）,no solution for λ 〉 λ＊,a unique solution for λ = λ＊.Furthermore,（＊） possesses at least two positive solutions when λ∈（0,λ＊） and 3 ≤ N ≤ *** N ≥ 6,under some monotonicity conditions of h we show that there exists a constant 0 〈λ＊＊〈 λ＊ such that problem（＊）possesses a unique solution for λ∈（0,λ＊＊）.

关键词： nonhomogeneous semilinear elliptic problems multiplicity uniqueness

A Compact 28 Ghz Millimeter Wave Antenna for Future Wireless Communication

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Computers, Materials & Continua 2022年第7期72卷 301-314页

作者： Shahid Khan adil ba.h.r haider Ali Abdul rauf Mohamed Marey hala Mostafa Ikram Syed LCOMS ASECUniversity de LorraineMetz57070France Department of Electrical and Computer Engineering Comsats University IslamabadAbbottabad Campus22060Pakistan Electrical Engineering Department Bahauddin Zakariya UniversityMultan60800Pakistan Department of Electronics Technology University of TechnologyNowshera24100Pakistan Department of Electrical Engineering National University of Sciences and TechnologyH-12Islamabad44000Pakistan Smart Systems Engineering Laboratory College of EngineeringPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Computer Software Engineering Military College of SignalsNational University of Sciences and TechnologyIslamabad44000Pakistan

This article presents a novel modified chuck wagon dinner bell shaped millimeter wave(mm-wave)antenna at 28 *** proposed design has ultra-thin rogers 5880 substrate with relative permittivity of *** design consists of T shaped resonating elements and two open ended side *** desired 28 Ghz frequency response is achieved by careful parametric modeling of the proposed *** maximum achieved single element gain at the desired resonance frequency is 3.45 *** efficiency of the proposed design over the operating band is more than 88%.The impedance bandwidth achieved for−10 dB reference value is nearly 2.9 *** proposed antenna is transformed into four element linear array which increases the gain up to 10.5 *** fabricated prototype is tested for the measured *** is observed that measured results closely match the simulated *** considering its simple structure and focused radiation patterns,the proposed design is well suited for IoT(Internet of Things),mmWave microwave sensing,5G and future rF(radio Frequency)frontends.

关键词： rF front-ends mmWave partial ground plane 28 Ghz IoT 5G antenna

Prediction Model for Cooling of an Electrical Unit with Time-Dependent heat Generation

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Journal of Mechanics Engineering and Automation 2012年第2期2卷 124-131页

作者： adil A. Alwan rafel h. hameed Mechanical Engineering Department University of Babylon Hilla P.O. Box. No .4 Iraq

The satisfactory performance of electrical equipments depends on their operating temperature. In order to maintain these devices within the safe temperature limits, an effective cooling is needed. high heat transfer rate of compact in size and reliable operation are the challenges of a thermal design engineer of electronic equipment. Then, it has been simulated the transient a three-dimensional model to study the heating phenomenon with two assumption values of heat generation. To control for the working of this equipment, cooling process was modeled by choosing one from different cooling technique. Constant low speed fan at one direction of air flow was used for cooling to predict the reducing of heating temperature through working of this equipment. Numerical Solution of finite difference time domain method （FDTD） has been utilized to simulate the temporal and spatial temperature profiles through two processes, which would minimize the solution errors.

关键词： Cooling by force convection cooling electronic equipment thermal analysis of electronic equipment numerical modeling of cooling electronic equipment.

OPTICAL ChArACTErIZATION OF TiO_2 ThIN FILM ON SILICON SUBSTrATE DEPOSITED BY DC rEACTIVE MAGNETrON SPUTTErING

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 194-198页

作者： h.Q.Wang h.Shen D.C.ba B.W.Wang L.S.Wen D.Chen SchoolofMechanismandAutomobile ShenyangInstituteofAeronauticalEngineeringShenyang110034Ghina／／MechanismandAeronauticalCollegeNortheasternUniversityShenyang110004China TheSchoolofPhysicsandEngineering ZhongshanUniversityGuangzhou510275Ghina MechanismandAeronauticalCollege NortheasternUniversityShenyang110004China GuangzhouInstimdeofEnergyConversion Guangzhou510070China InstituteofMetalresearch TheChineseAcademyofSciencesShenyang110016China MaterialandScienceEngineeringAcademy SouthChinaUniversityofTechnologyGuangzhou510641China

TiO2 thin film has attracted considerable attention in recent years, due to its different refractive index and transparency with amorphous and different crysta ls in the visible and near-infrared wavelength region, high dielectric constant, wide band gap, high wear resistance and stability, etc, for which make it being used in many fields. This paper aims to investigate the optical characterizatio n of thin film TiO2 on silicon wafer. The TiO2 thin films were prepared by DC re active magnetron sputtering process from Ti target. The reflectivity of the film s was measured by UV-3101PC, and the index of refraction (n) and extinction coef ficient (k) were measured by n & k Analyzer 1200.

关键词： optical characterization TiO2 thin film DC reactive magnetron sputtering n & k

Thermal Pyrolysis of Waste Disposable Plastic Syringes and Pyrolysis Thermodynamics

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Advances in Chemical Engineering and Science 2022年第2期12卷 96-113页

作者： adil Koç Department of Chemical Engineering Faculty of Engineering University of &#304 nö nü Malatya Turkey

In this study, the convertibility of disposable plastic waste injectors made of hDPE and PP plastics into valuable chemical products by thermal pyrolysis was investigated. While PP plastic wastes were decomposed in the temperature range of 400°C - 445°C, hDPE plastic wastes were decomposed in the higher temperature range (430°C - 475°C). Although the physical appearance of the liquid products obtained in the thermal decomposition of PP plastic wastes are lighter in color and fluid, it has been observed that the liquid decomposition products of hDPE plastic wastes have a more dense and viscous structure. By using the first-order kinetic model, kinetic expressions for both plastic wastes were derived, reaction rate constants, k, and activation energy, Eact, and thermodynamic quantities such as reaction enthalpy, △h≠, reaction entropy, △S≠ ve and Gibbs free energy, △G≠ were calculated. In the thermal pyrolysis of PP and hDPE plastic wastes, Eact, △h≠, △G≠, △S≠ values are 162.30 kJ/mol, 156.52 kJ/mol, 219.50 kJ/mol, -87.71 J/molK, and 201.80 kJ/mol, 195.77 kJ/mol, and 229.14 kJ/mol, -46.48 J/molK, respectively. These thermodynamic quantities calculated for both plastic wastes show that the pyrolytic decomposition studies carried out in an inert gas atmosphere have endothermic reaction behavior.

关键词： Plastic Waste Injector rate Constant Thermodynamic Quantities

Pros and cons of live kidney donation in prediabetics: A critical review and way forward

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World Journal of Transplantation 2024年第1期14卷 12-31页

作者： Muhammad Abdul Mabood Khalil Nihal Mohammed Sadagah Jackson Tan Furrukh Omair Syed Vui heng Chong Salem h Al-Qurashi Center of renal Diseases and Transplantation King Fahad Armed Forces Hospital JeddahJeddah 23311Saudi Arabia Department of Nephrology RIPAS Hospital Brunei DarussalamBrunei Muara BA1710Brunei Darussalam Division of Gastroenterology and hepatology Department of MedicineRaja Isteri Pengiran Anak Saleha HospitalBandar Seri Begawan BA1710Brunei Darussalam

There is shortage of organs,including kidneys,*** with deceased kidney transplantation,there is a significant rise in live kidney *** prevalence of prediabetes(PD),including impaired fasting glucose and impaired glucose tolerance,is on the rise across the *** teams frequently come across prediabetic kidney donors for *** are at risk of diabetes,chronic kidney disease,cardiovascular events,stroke,neuropathy,retinopathy,dementia,depression and nonalcoholic liver disease along with increased risk of all-cause ***,most of the studies done in prediabetic kidney donors are retrospective in nature and have a short follow up *** is lack of prospective long-term studies to know about the real risk of complications after ***,there are variations in recommendations from various guidelines across the globe for donations in prediabetics,leading to more confusion among *** increases the responsibility of transplant teams to take appropriate decisions in the best interest of both donors and *** review focuses on pathophysiological changes of PD in kidneys,potential complications of PD,other risk factors for development of type 2 diabetes,a review of guidelines for kidney donation,the potential role of diabetes risk score and calculator in kidney donors and the way forward for the evaluation and selection of prediabetic kidney donors.

关键词： Live kidney donation Prediabetes Impaired fasting glucose Impaired glucose tolerance review