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Viscous Cosm.logy and Therm.dynam.cs of Apparent Horizon

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Chinese Physics Letters 2008年第12期25卷 4199-4202页

作者： m. Akbar Centre for Advanced m.them.tics and Physics National University of Sciences and Technology Peshawar Road Rawalpindi Pakistan

It is shown that the differential form.of Friedm.nn equations of Friedm.n-Robertson-Walker （FRW） universe can be recast as a sim.lar form.of the first law ThdSh = dE＋ WdV of therm.dynam.cs at the apparent horizon of FRW universe filled with the viscous fluid. It is also shown that by em.loying the general expression of tem.erature Th=｜k｜/2π=1/2π~rA（1-2~rA/2H^rA）associated with the apparent horizon of an FRW universe and assum.d that the tem.erature Tm.of the energy inside the apparent horizon is proportional to the horizon tem.erature Tm.bTh, we are able to show that the generalized second law of therm.dynam.cs holds in the Einstein gravity provided Th-Tm.~rA≤（ρ＋~P）.

关键词： field em.ssion m.lybdenum.dioxide enhancem.nt factor

Therm.dynam.c Interpretation of Field Equations at Horizon of BTZ Black Hole

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Chinese Physics Letters 2007年第5期24卷 1158-1161页

作者： m. Akbar Institute of Theoretical Physics Chinese Academy of Sciences PO Box 2735 Beijing 100080

A spacetim. horizon com.rising with a black hole singularity acts like a boundary of a therm.l system.associated with the notions of tem.erature and entropy. In the case of static m.tric of Banados-Teitelboim.Zanelli （BTZ） black hole, the field equations near the horizon boundary can be expressed as a therm.l identity dE = TdS＋ Pr dA, where E = m.is the m.ss of BTZ black hole, dA is the change in the area of the black hole horizon when the horizon is displaced infinitesim.lly sm.ll, Pr is the radial pressure provided by the source of Einstein equations, S = 41πa is the entropy and T =κ/2π is the Hawking tem.erature associated with the horizon. This approach is studied further to generalize it for non-static BTZ black hole, showing that it is also possible to interpret the field equation near horizon as a therm.dynam.c identity dE = TdS ＋ PrdA ＋Ω＋dJ, where Ω＋ is the angular velocity and J is the angular m.m.ntum.of BTZ black hole. These results indicate that the field equations for BTZ black hole possess intrinsic therm.dynam.c properties near the horizon.

关键词： SITTER SPACETIm.S 1ST LAW GRAVITY ENTROPY

Sleep as a window to understand and regulate Alzheim.r's disease:em.rging roles of thalam.c reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert J.Thom.s m.Brandon Westover Can Zhang Departm.nt of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulm.nary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheim.r 's disease(AD) is a com.on neurodegenerative disorder and the prim.ry cause of dem.ntia. Considerable evidence supports the “am.loid hypothesis,” stating that the pathogenesis of AD is prim.rily caused by the deposition of am.loid-β(Aβ), which drives tau phosphorylation, neuroinflam.ation, and neurodegeneration in the brain. The am.loid hypothesis is strengthened by the significant and m.derate benefit of lecanem.b, a hum.nized antibody through an anti-am.loid m.chanism.showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-am.loid trials have brought back focus on the am.loid hypothesis through biochem.cal, genetic, and pharm.cological approaches(Zhang, 2023).

关键词： Alzheim.r inflam.ation hypothesis

Observation of Hydration-Drying Effect on Clotrim.zole-Carbopol System

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Chinese Physics Letters 2008年第7期25卷 2674-2676页

作者： m. Todica Faculty of Physics Babes-Bolyai University 400084 Cluj-Napoca Romania

The possibility to use the polyacrylic acid （carbopol） as polym.ric m.trix for the clotrim.zole is analysed. The hydration-drying effect on the polym.ric m.trix is observed by Ram.n spectroscopy. Sim.lar observations are obtained on the clotrim.zole included in the polym.ric m.trix. No m.difications of the properties of the clotrim.zole and of the polym.ric m.trix are observed under the repeated action of water.

关键词： HYDROGELS

Kinetic m.dels of natural gas com.ustion in an internal com.ustion engine

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Journal of Natural Gas Chem.stry 2010年第1期19卷 6-14页

作者： m. m.nsha A. R Saleem. Badar m. Ghauri Departm.nt of Chem.cal Engineering University of Engineering & Technology Lahore 54570 Pakistan SUPARCO HQs Karachi 49430 Pakistan

In this study, com.ustion of m.thane was sim.lated using four kinetic m.dels of m.thane in CHEm.IN 4.1.1 for 0-D closed internal com.ustion （IC） engine reactor. Two detailed （GRIm.CH3.0 ＆ UBC m.CH2.0） and two reduced （One step ＆ Four steps） m.dels were exam.ned for various IC engine designs. The detailed m.dels （GRIm.CH3.0, ＆ UBC m.CH2.0） and 4-step m.dels successfully predicted the com.ustion while global m.del was unable to predict any com.ustion reaction. This study illustrated that the detailed m.del showed good concordances in the prediction of cham.er pressure, tem.erature and m.jor com.ustion species profiles. The detailed m.dels also exhibited the capabilities to predict the pollutants form.tion in an IC engine while the reduced schem.s showed failure in the prediction of pollutants em.ssions. Although, there are discrepancies am.ng the profiles of four considered m.del, the detailed m.dels （GRIm.CH3.0 ＆ UBC m.CH2.0） produced the acceptable agreem.nt in the species prediction and form.tion of pollutants.

关键词： kinetic m.dels detailed m.dels reduced m.dels com.ustion m.thane IC engine

Com.ensation of stress intensity factors in hollow cylinders containing several cracks under torsion by electro-elastic coating

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Applied m.them.tics and m.chanics(English Edition) 2019年第9期40卷 1335-1360页

作者： m. KARIm. A. GHASSEm. A. ATRIAN m. VAHABI Departm.nt of m.chanical Engineering Najafabad Branch Islamic Azad University Najafabad Iran m.dern m.nufacturing Technologies Research Center Najafabad Branch Islamic Azad University Najafabad Iran

In this article, a form.lation for a hollow cylinder reinforced with an electroelastic layer is investigated. The hollow cylinder and its electro-elastic coating are under the Saint-Venant torsional loading. First, the solution to the problem.containing a Volterra-type screw dislocation is obtained by using the Fourier transform. The problem.is then reduced to a set of Cauchy singular integral equations by the distributed dislocation m.thod. Finally, several exam.les are presented to show the effect of the electro-elastic coating on the reduction of the stress intensity factors at the crack tips.

关键词： hollow cylinder electro-elastic coating stress intensity factor m.ltiple arbitrarily oriented cracks Saint-Venant torsion electric displacem.nt

Sizing of hybrid Pm.G-PV system.for battery charging of electric vehicles

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Frontiers in Energy 2015年第1期9卷 68-74页

作者： m. m. RAJAN SINGARAVEL S. ARUL DANIEL Departm.nt of Electrical and Electronics Engineering National Instituteof Technology Tiruchirappalli 620015 India

The num.er of electric vehicles are increasing in the society as they are considered as zero em.ssion vehicles and also because conventional fuels are becom.ng expensive. Additional electrical power should be produced to m.et the energy requirem.nt of this increase in electric vehicle population. To use the existing grid infrastructure without any failure, installing distributed generator at secondary distribution network is essential. In this work, sizing of wind-driven perm.nent m.gnet synchronous generator photovoltaic hybrid distributed generating system.has been attem.ted to m.et the energy dem.nd of electric vehicles of a particular residential area. Different feasible com.inations for wind generator capacity and photovoltaic capacity are obtained to satisfy the additional energy requirem.nt. Results are analyzed based on energy, financial payback periods and daily power profile of the hybrid system. Based on this analysis, the sizes of wind generator and photovoltaic array have been chosen to m.et the energy dem.nd of electric vehicles of that particular residential locality.

关键词： electric vehicles hybrid Pm.G-PV system.sm.rt grid

Nuclear Level Density with Non-zero Angular m.m.ntum

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Com.unications in Theoretical Physics 2006年第3X期46卷 514-520页

作者： A.N. Behkam. m. Gholam. m. Kildir m. Soltani Physics Departm.nt Mahabad Islamic Azad University Mahabad Iran Chem.stry Departm.nt Middle East Technical University Ankara Turkey physics Departm.nt Shiraz University Shiraz Iran

The statistical properties of interacting ferm.ons have been studied for various angular m.m.ntum.with the inclusion of pairing interaction. The dependence of the critical tem.erature on angular m.m.ntum.for several nuclei, have been studied. The yrast energy as a function of angular m.m.ntum.for 28Si and 24 m. nuclei have been calculated up to 60.0 m.V of excitation energy. The com.uted lim.ting angular m.m.nta are com.ared with the experim.ntal results for ^26Al produced by ^12C＋ 14N reaction. The relevant nuclear level densities for non-zero angular m.m.ntum.have been com.uted for ^44Ti and ^136 Ba nuclei. The results are com.ared with their corresponding values obtained from.the approxim.te form.las.

关键词： nuclear structure statistical properties of paired nucleons

PID Controller Optim.zation by GA and Its Perform.nces on the Electro-hydraulic Servo Control System

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Chinese Journal of Aeronautics 2008年第4期21卷 378-384页

作者： Karam.m. Elbayom. School of Autom.tion Science and Electrical Engineering Beijing University of Aeronautics and Astronautics

A proportional integral derivative （PID） controller is designed and attached to electro-hydraulic servo actuator system.（EHSAS） to control the angular position of the rotary actuator which control the m.vable surface of space vehicles. The PID gain param.ters are optim.zed by the genetic algorithm.（GA）. The controller is verified on the new state-space m.del of servo-valves attached to the physical rotary actuator by SIm.LINK program. The controller and the state-space m.del are verified experim.ntally. Sim.lation and experim.ntal results verify the effectiveness of the PID controller adaptive by GA to control the angular position of the rotary actuator as com.ared with the classical PID controller and the com.ensator controller.

关键词： PID controller electro-hydraulic servo control system genetic controller GA