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Normal Crossings Degenerations of Symplectic Manifolds

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Peking Mathematical Journal 2019年第3期2卷 275-351页

作者： mohammad farajzadeh tehrani Aleksey Zinger Simons Center for Geometry and Physics Stony Brook UniversityStony BrookNY 11794USA Department of Mathematics The University of IowaIowa CityIA 52242USA Department of Mathematics Stony Brook UniversityStony BrookNY 11794USA

We use local Hamiltonian torus actions to degenerate a symplectic manifold to a normal crossings symplectic variety in a smooth one-parameter *** construction,motivated in part by the Gross-Siebert and ***’s programs,contains a multifold version of the usual(two-fold)symplectic cut construction and in particular splits a symplectic manifold into several symplectic manifolds containing normal crossings symplectic divisors with shared irreducible components in one step.

关键词： symplectic manifold irreducible

Liquid injectivity in a SAG foam process:Effect of permeability

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Petroleum Science 2024年第1期21卷 302-314页

作者： Jia-Kun Gong Yuan Wang Ridhwan-Zhafri B.Kamarul Bahrim Raj-Deo Tewari mohammad-Iqbal Mahamad Amir Rouhi farajzadeh William Rossen College of Mechanics and Materials Hohai UniversityNanjing210098JiangsuChina College of Water Conservancy&Hydropower Engineering Hohai UniversityNanjing210098JiangsuChina PETRONAS Kuala Lumpur50088Malaysia Department of Geoscience and Engineering Delft University of Technology2628 CNDelftthe Netherlands Shell Global Solutions International B.V. 1031 HWAmsterdamthe Netherlands

Foam is utilized in enhanced oil recovery and CO_(2) ***-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in *** previous studies with similar permeability cores show that during SAG injection,several banks occupy the area near the well where fluid exhibits distinct ***,underground reservoirs are heterogeneous,often *** is crucial to understand the effect of permeability on fluid behaviour and injectivity in a SAG *** this work,coreflood experiments are conducted in cores with permeabilities ranging from 16 to 2300 *** observe the same sequence of banks in cores with different ***,the speed at which banks propagate and their overall mobility can vary depending on *** higher permeabilities,the gas-dissolution bank and the forced-imbibition bank progress more rapidly during liquid *** total mobilities of both banks decrease with *** utilizing a bank-propagation model,we scale up our experimental findings and compare them to results obtained using the Peaceman *** findings reveal that the liquid injectivity in a SAG foam process is misestimated by conventional simulators based on the Peaceman *** lower the formation permeability,the greater the error.

关键词： Foam Enhanced oil recovery Surfactant-alternating-gas Injectivity Permeability

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad M.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

Recent Progress in Bionic Hydrogels for Articular Cartilage:Tribological and Mechanical Characteristics

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Journal of Bionic Engineering 2024年第2期21卷 653-673页

作者： mohammad Javan Almasi Dangsheng Xiong School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Cartilage regeneration and repair are considered clinical challenges since cartilage has limited capability for *** tissue-engineered materials have the ability to repair cartilage,they have weak mechanical characteristics and cannot resist long-term *** the other hand,surgery to replace the joint is frequently done to treat significant cartilage deterioration these ***,the materials that are being used for replacement have high friction coefficients,lack shock absorption functions,and lack *** research on natural articular cartilage structure and function may lead to bionic hydrogels,which have suitable physicochemical and biological characteristics(e.g.,tribological and mechanical properties and the ability to support loadbearing capability),but need *** on their tribological and mechanical characteristics,the current review highlights the most recent advancements of bionic hydrogels used for articular cartilage,highlighting both the field's recent progress and its potential for future *** this reason,firstly,some important property improvement methods of bionic hydrogels are discussed and then,the recent findings of various research on the making of those bionic materials are provided and *** seems that by using some modifications such as product design,surface treatments,animal tests,controlling the isoelectric point of hydrogels,and computer simulation,the intended mechanical and tribological characteristics of natural articular cartilage may be attained by the bionic hydrogels.

关键词： Bionic hydrogel Articular cartilage Mechanical property Tribological property Lubrication

Ultrasensitive plasmonic sensor based on MDM waveguide containing Persian Orsi window cavities for refractive index and blood plasma sensing

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Optoelectronics Letters 2024年第7期20卷 406-411页

作者： mohammad Ghanavati mohammad Azim Karami School of Electrical Engineering Iran University of Science and Technology

We developed a plasmonic refractive index（RI） with a metal-dielectric-metal（MDM） structure that utilizes two Persian Orsi windows-like separated cavities with a high figure of merit（FoM） and ultrasensitivity. The simulated and optimized Ag-air-Ag MDM sensor for surface plasmon resonance（SPR） offers high RI sensitivity（SRI） and the ability to detect blood plasma concentration（BPC）. The results verified that structural parameters have an effect on SRI, full width at half maximum（FWHM）, FoM, sensitivity of blood plasma（Sp） for right and left peaks, whose values are 1 345.45 nm·RIU-1, 32 nm, 42.04 RIU-1, 0.26 and 0.19 nm·L·g-1, respectively. The proposed design opens a new horizon in sensor development.

关键词： A

The modeling non-sequential double ionization of helium atom under highintensity femtosecond laser pulses with shielding charge approximation

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Communications in Theoretical Physics 2024年第2期76卷 151-156页

作者： Marjan Zakavi mohammad Sabaeian Department of Physics Faculty of ScienceShahid Chamran University of AhvazIran Center for Research on Laser and Plasma Shahid Chamran University of AhvazIran

In this study,we successfully extracted the‘knee structure’for non-sequential double ionization(NSDI)in the helium *** achieve this,for the first time,we solved the time-dependent Schrödinger equation in three dimensions for the helium atom,utilizing the shielding charge *** findings corroborate prior observations by Wang et al[Wang and Eberly,***.105,083001(2010)],demonstrating that NSDI occurs within a narrower time window in circular polarization compared to linear *** a result,the yield of linear polarization was higher than that of circular polarization,aligning with the previously reported ***,in the case of circular polarization,the time window further narrows with increasing intensity,attributed to a decrease in the time-of-flight.

关键词： NSDI knee structure TDSE shielding charge helium 3D-TDSE

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： mohammad Saifullah Vinay K.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Sacrificial piles as a countermeasure against local scour around underwater pipelines

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Water Science and Engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi Seyed mohammad Ali Zomorodiann Masih Zolghadr Hazi mohammad Azamathulla Department of Water Engineering Shiraz UniversityShiraz ***Iran Department of Water Sciences Engineering Jahrom UniversityJahrom ***Iran Department of Civil and Environmental Engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant *** can lead to failure of the pipelines resulting in environmental side effects and economic *** study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial *** sizes of sacrificial piles were examined in a linear *** piles were installed on the upstream side of the pipeline at three *** scour depth reduction rates below the pipeline were *** results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the *** sediment accumulation reduced the scour depth beneath the *** of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of *** the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar *** the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water River crossing pipeline Local scour Self-burial process Sediment transport

Developing a phenomenological model to simulate single and mixed scale formation during flow in porous media:Coupling a salt precipitation model with an ion transport equation under dynamic conditions

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Petroleum Research 2024年第1期9卷 17-36页

作者： Erfan Hosseini Dana mohammad Nazar Negar Hosseini mohammad Sarmadivaleh Exploration Directorate National Iranian Oil Company(NIOC)TehranIran Institute of Physical Chemistry and Polymer Physics Leibniz Institute of Polymer Research DresdenDresdenGermany Department of Petroleum Engineering Islamic Azad University(IAU)IlamIran WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWestern AustraliaAustralia

Water flooding and pressure maintenance are recommended to improve oil recovery practices after low recovery of petroleum reservoirs occurs during primary *** crystal formation is a frequent occurrence when using these *** experimental,numerical,and theoretical studies have been done on the mechanisms underlying scaling and permeability reduction in porous media;however,there has not been a satisfactory model *** study developed a phenomenological model to predict formation damage caused by salt *** with existing models,which provide a scaling tendency,the proposed model predicts the profile of scale *** salt precipitation model simulates reactive fluid flow through porous media.A thermodynamic,kinetic,and flow hydrodynamic model was developed and coupled with the ion transport equation to describe the movement of ***,a set of carefully designed dynamic experiments were conducted and the data were compared with the model *** forecasts and experimental data were observed to have an average absolute error(AAE)ranging from 0.68%to 5.94%,which indicates the model's suitability.

关键词： Improved oil recovery Water flooding Formation damage Scaling tendency Salt precipitation