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Two-Way Interactions Between Equatorially-Trapped Waves and the Barotropic Flow

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Chinese Annals of Mathematics,Series B 2009年第5期30卷 539-568页

作者： James FERGUSON Boualem KHOUIDER maryam NAMAZI Department of Mathematics and Statistics University of Victoria Department of Mathematics and Statistics University of VictoriaPO BOX 3045 STN CSC Victoria

Lateral energy exchange between the tropics and the midlatitudes is a topic of great importance for understanding Earth＇s climate system. In this paper, the authors address this issue in an idealized set up through simple shallow water models for the interactions between equatorially trapped waves and the barotropic mode, which supports Rossby waves that propagate poleward and can excite midlatitude teleconnection patterns. It is found here that the interactions between a Kelvin wave and a fixed meridionai shear （mimicking the jet stream） generates a non-trivial meridional velocity and meridional convergence in phase with the upward motion that can attain a maximum of about 50%, which oscillates on frequencies ranging from one day to 10 days. When, on the other hand, the barotropic flow is forced by slowly propagating Kelvin waves a complex flow pattern emerges; it consists of a phase-locked barotropic response that is equatoriaily trapped and that propagates eastward with the forcing Kelvin wave and a certain number of planetary Rossby waves that propagate westward and toward the poles as seen in nature. It is suggested here that the poleward propagating waves are to some sort of multi-way resonant interaction with the phase locked response. Moreover, it is shown here that a numerical scheme with dispersion properties that depend on the direction perpendicular to the direction of propagation, namely the 2D central scheme of Nessyahu and Tadmor, can artificially alter significantly the topology of the wave fields and thus should be avoided in climate models.

关键词： Equatorially trapped waves Wave interactions Jet stream Rossby waves Phase locked Dispersion relation Central scheme Climate modeling

Thermomechanical response of aluminum alloys under the combined action of tensile loading and laser irradiations

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Chinese Physics B 2018年第3期27卷 469-480页

作者： Mohsan Jelani Zewen Li Zhonghua Shen maryam Sardar School of Science Nanjing University of Science and Technology Nanjing 210094 China Advanced Launching Co-Innovation Centre Nanjing University of Science and Technology Nanjing 210094 China

This study reports the investigation of the thermomechanical behavior of aluminum alloys （AI-1060, A1-6061, and A1-7075） under the combined action of tensile loading and laser irradiations. The continuous wave ytterbium fiber laser （wavelength 1080 nm） was employed as the irradiation source, while tensile loading was provided by the tensile testing machine. The effects of various pre-loading and laser power densities on the failure time, temperature distribution, and the deformation behavior of aluminum alloys are analyzed. The experimental results represent the significant reduction in failure time for higher laser power densities and for high preloading values, which implies that preloading may contribute a significant role in the failure of the material at elevated temperature. Fracture on a microscopic scale was predominantly ductile comprising micro-void nucleation, growth, and coalescence. The AI-1060 specimens behaved plastically to some extent, while A1-6061 and A1-7075 specimens experienced catastrophic failure. The reason and characterization of ma- terial failure by tensile and laser loading are explored in detail. A comparative behavior of under-tested materials is also investigated. This work suggests that studies considering only combined loading are not enough to fully understand the mechanical behavior of under-tested materials. For complete characterization, one should consider the effect of heating as well as loading rate and the corresponding involved processes with the help of thermomechanical coupling and the thermal elastic-plastic theory.

关键词： aluminum alloys fiber laser tensile loading thermomechanical effects failure evolution

Homological Dimensions with Respect to a Semidualizing Module and Tensor Products of Algebras

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Algebra Colloquium 2015年第2期22卷 215-222页

作者： maryam Salimi Elham Tavasoli Siamak Yassemi Department of Mathematics East Tehran Branch Islamic Azad University Tehran Iran Department of Mathematics University of Tehran Tehran IranSchool of Mathematics Institute for Research in Fundamental Sciences (IPM) Tehran Iran

Let C be a semidualizing module for a commutative ring R. It is shown that the ：IC-injective dimension has the ability to detect the regularity of R as well as the Pc-projective dimension. It is proved that if D is dualizing for a Noetherian ring R such that idR（D） = n 〈 ∞, then ：ID-idR（F） ≤ n for every flat R-module F. This extends the result due to Enochs and Jenda. Finally, over a Noetherian ring R, it is shown that if M is a pure submodule of an R-module N, then/TC-idR（M） ≤ IC-idR（N）. This generalizes the result of Enochs and Holm.

关键词： semidualizing C-projectives C-injectives pure submodules

Mobilizing the seed storage oil in milk thistle (Silybum marianum) can supply energy for seed germination and early seedling growth and apply as TAGs breakdown marker

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Oil Crop Science 2023年第4期8卷 207-216页

作者： Mohammad Shahin Daneshmandi maryam Mohammadi maryam Asadi Adele Robati Department of Plant Production Faculty of Agriculture Science and Natural ResourcesUniversity of Torbat HeydariehP.O.Box 95161-68595Torbat HeydariehIran

Milk thistle(Silybum marianum)is a crucial medicinal plant containing a large amount of *** the study,the changes in storage oil during seed germination and seedling transition from heterotrophic phases were *** results showed that seed oil decreased from 19.53%to 0.88%on the 7th day of seedling *** hydrolysis continued until the 4th day of germination with a low slope,but then increased the use of oils in seed germination end seedling growth *** results indicated that the quantitative changes in fatty acids,presented at lower amount,were relatively higher than dominant fatty *** were decreasing phenolic content in the developing seedlings,but overall,lowest level of total phenolic content can be attributed to the control(30.52 mg⋅100 g⋅Oil^(-1)).In contrast,the maximum peroxide value(2.58 meq⋅kg Oil^(-1))in the developing seedling was observed on the last day of the *** results showed that there was a significant correlation between saturated fatty acid,unsaturated fatty acid,and lipase ***,the correlation between lipase activity and polyunsaturated fatty acids was significantly higher than between lipase activity and monounsaturated fatty acids(R^(2)=90%and R^(2)=77%,respectively).Therefore,the lipolysis process acts selectively in milk thistle *** to the results,C12:0 exhibits a greater impact on the early seedling growth rather than on the germination process and is one of the determining factors in the transition from heterotroph to ***,it can be a marker for TAGs breakdown.

关键词： Fatty acid Lipase Milk thistle Lauric acid TAGs Total polyphenol

Ga-(Nb+Ta)-(Nb/Ta)(Zr/Hf) Ternary Diagram: An Excellent Tool for Discriminating Barren and Ta-Hosting Granite-Pegmatite Systems

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Journal of Earth Science 2020年第3期31卷 551-558页

作者： maryam Mohamadizadeh Seyed Hossein Mojtahedzadeh Farimah Ayati Mining and Metallurgical Engineering Department Yazd UniversityYazd 98195-741Iran Department of Geology Payame Noor University19395-4697 TehranIran

Discriminating barren and fertile intrusions is one of the main challenges in the search for rare-element *** comprising more than one element can make discrimination of productive and barren samples more *** diagrams distinguish samples by simultaneous means of positive and/or negative correlations between variables.A ternary diagram for S-type peraluminous granites has been obtained in this ***,a database composed of Ta-bearing and barren granitic systems was created,then geochemical behavior of trace elements was studied,and statistical investigations were done using GCDkit software,which resulted in the Ga-(Nb+Ta)-(Nb/Ta)(Zr/Hf)ternary diagram which can distinguish the non-mineralized granites from productive *** Ta-bearing samples,which are situated in the fertile field in the diagram,are those which have high Nb and Ta contents,elevated Ga content and the lowest Nb/Ta and Zr/Hf values.

关键词： tantalum mineralization S-type peraluminous granite discrimination of fertile and barren granites whole-rock geochemistry indicators

Recent tectonic activity in Central Alborz Mountain,Iran:morphometric analysis and knickpoint identification

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Journal of Mountain Science 2020年第12期17卷 3137-3161页

作者： Parisa SHOKRI maryam DEHBOZORGI Saeid HAKIMI ASIABAR Department of Earth Science Kharazmi UniversityTehran15719-14911Iran Department of Geology Lahijan BranchAzad UniversityGilan1616Iran

Alborz,as part of the Alpine-Himalayan orogeny belt,has been the result of the convergence of the Central Iranian and Eurasian plate since the late *** study area located in Central Alborz encompasses different Quaternary ***,the present study aimed to evaluate the effect of faults on river landforms through morphotectonic indices and the causes of knickpoints and knickzones in the Bedrock Rivers in part of Central *** this end,six morphometric indices such as longitudinal gradient(SL),hierarchical anomaly(Δα),the bifurcation index(R),hypsometric integral and hypsometric curve(Hi-Hc),relative relief(Bh),and basin shape(Bs) were calculated and analyzed in38 sub-basins of the ***,the area was divided into extremely high,high,medium,and low tectonic activity areas using the relative tectonic activity(IAT).Normalized steepness and concavity indices along with the longitudinal profiles of the streams were obtained using Matlab and Arc GIS *** on the findings,the existence of slope-break knickpoints at the mountain piedmont at the outlet of large rivers through active faults demonstrated that most of these landforms were created by movements along the main faults such as Khazar,Nusha,Soheil,Deylaman,Kashachal,representing high tectonic activity in the central and southern parts of the study ***,the values of these indices were extremely low and indicated low tectonic activity in the northern parts located in the embayment part of the Caspian ***,the findings revealed that these classes correspond well to the areas with landforms such as V-shaped and narrow valleys,gorges,deflected and offset streams,deformed Neogene,and Quaternary units that indicate the post-Neogene activity.

关键词： Morphotectonic Bedrock rivers Knickpoint Quaternary Fault Uplift Central Alborz

Quantum speedup and non-Markovianity of an atom in structured reservoirs:pseudomodes as a good description of environmental memory

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Communications in Theoretical Physics 2024年第8期76卷 60-66页

作者： maryam Hadipour Soroush Haseli Saeed Haddadi Faculty of Physics Urmia University of TechnologyUrmiaIran School of Physics Institute for Research in Fundamental Sciences(IPM)PO Box 19395-5531TehranIran Faculty of Physics Semnan UniversityPO Box 35195-363SemnanIran

Following the recent paper(Teittinen et al 2019 New J. Phys. 21 123041), one can see that in general there is no simple relation between non-Markovianity and quantum speed limit. Here, we investigate the connection between quantum speed limit time and non-Markovianity of an atom in structured environments(reservoirs) whose dynamics is governed by an exact pseudomode master equation(Garraway 1997 Phys. Rev. A 55 2290). In particular, we find an inverse relation between them, which means that the non-Markovian feature of the quantum process leads to speedup of evolution. Thus, there is a link between quantum speedup and memory effects for specific cases of dynamical evolution. Our results might shed light on the relationship between the speedup of quantum evolution and the backflow of information from the environment to the system.

关键词： quantum speed limit non-Markovianity pseudomode method structured environments

Deflection amplification factor for estimating seismic lateral deformations of RC frames

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Earthquake Engineering and Engineering Vibration 2015年第2期14卷 373-384页

作者： maryam Samimifar Asghar Vatani Oskouei Fayaz Rahimzadeh Rofooei Department of Civil Engineering Shahid Rajaee Teacher Training University Department of Civil Engineering Kharazmi University Department of Civil Engineering Sharif University of Technology

Different values have been assigned to the ratio of the defl ection amplifi cation factor(Cd) to the response modifi cation factor(R) for a specifi ed force-resisting system in the seismic design provisions while the same application is defi ned for it. An analytical study of the seismic responses of several reinforced concrete frames subjected to a suite of earthquake records performed in this research indicate that the stories’ overstrength and stiffness distribution along the structural height can affect local defl ections more than global ones. Therefore, the Cd/R ratio is calculated based on the ratio of both maximum inelastic to maximum elastic displacements and interstory drifts. Due to damage concentration in some specifi c stories, the defl ection amplifi cation factor calculated based on inelastic interstory drifts was larger than that of the inelastic displacements. Consequently, a minimum value of 1.0 is recommended for the Cd/R ratio in order to estimate maximum inelastic drifts. The ratio of inelastic to elastic displacement was generally found to increase slightly along the structural height for the studied RC models. In addition, it was detected that the story damage indices of the studied RC frames decrease when the inverted value of inelastic interstory drift ratios are increased through a(negative) power form.

关键词： deflection amplification factor nonlinear dynamic

Synthesis of linear low-density polyethylene-g-poly(acrylic acid)-co-starch/organo-montmorillonite hydrogel composite as an adsorbent for removal of Pb(Ⅱ) from aqueous solutions

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Journal of Environmental Sciences 2015年第1期27卷 9-20页

作者： maryam Irani Hanafi Ismail Zulkifli Ahmad Maohong Fan School of Materials and Mineral Resources Engineering USM Engineering Campus Universiti Sains Malaysia Department of Chemical and Petroleum Engineering University of Wyoming

The purpose of this work is to remove Pb（II） from the aqueous solution using a type of hydrogel composite. A hydrogel composite consisting of waste linear low density polyethylene, acrylic acid, starch, and organo-montmorillonite was prepared through emulsion polymerization method. Fourier transform infrared spectroscopy（FTIR）, Solid carbon nuclear magnetic resonance spectroscopy（CNMR））, silicon-29 nuclear magnetic resonance spectroscopy（Si NMR））, and X-ray diffraction spectroscope（（XRD） were applied to characterize the hydrogel composite. The hydrogel composite was then employed as an adsorbent for the removal of Pb（II） from the aqueous solution. The Pb（II）-loaded hydrogel composite was characterized using Fourier transform infrared spectroscopy（FTIR））,scanning electron microscopy（SEM））, and X-ray photoelectron spectroscopy（（XPS））. From XPS results, it was found that the carboxyl and hydroxyl groups of the hydrogel composite participated in the removal of Pb（II）. Kinetic studies indicated that the adsorption of Pb（II）followed the pseudo-second-order equation. It was also found that the Langmuir model described the adsorption isotherm better than the Freundlich isotherm. The maximum removal capacity of the hydrogel composite for Pb（II） ions was 430 mg/g. Thus, the waste linear low-density polyethylene-g-poly（acrylic acid）-co-starch/organo-montmorillonite hydrogel composite could be a promising Pb（II） adsorbent.

关键词： Hydrogel Waste polymers Organo clay Heavy metal ions Adsorption mechanism