نتایج جستجو برای: nonlocal and length scale parameters

تعداد نتایج: 16955907  

Journal: :international journal of nano dimension 0
r. ansari department of mechanical engineering, university of guilan, p.o. box 3756, rasht, iran h. rouhi department of mechanical engineering, university of guilan, p.o. box 3756, rasht, iran

in this paper, the stability characteristics of single-walled carbon nanotubes (swcnts) under the action of axial load are investigated. to this end, a nonlocal flügge shell model is developed to accommodate the small length scale effects. the analytical rayleigh-ritz method with beam functions is applied to the variational statement derived from the flügge-type buckling equations. molecular dy...

A Fatahi-Vajari A. Imam,

This paper investigates the lateral vibration of single-layered graphene sheets based on a new theory called doublet mechanics with a length scale parameter. After a brief reviewing of doublet mechanics fundamentals, a sixth order partial differential equation that governs the lateral vibration of single-layered graphene sheets is derived. Using doublet mechanics, the relation between natural f...

In the present study, free vibration behaviors of of carbon nanotube (CNT) and boron nitride nanotube (BNNT) have been investigated via Eringen’s nonlocal continuum theory. Size effect has been considered via nonlocal continuum theory. Nanotubes have become popular in the world of science thanks to their characteristic properties. In this study, free vibrations of Boron Nitride Nanotube (BNNT) ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه بیرجند - دانشکده کشاورزی 1390

abstract this study is carried out to determine the chemical composition in the three vegetative stages of the haloxylon sp., degradation parameters, with adding naoh and ca(oh2 ). for this purpose, in may and october and january 2010 enough some haloxylon sp. of the ammary area was prepared. crude protein and ash percentage are decrease, neutral detergent fiber percentage with pragress stage ...

The main goal of this research is to provide a more detailed investigation of the size-dependent response of magneto-electro-thermo-elastic (METE) nanobeams subjected to propagating wave, ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - پژوهشکده مهندسی فرایند 1395

abstract: mineral scaling in oil and gas production equipment is one of the most important problem that occurs while water injection and it has been recognized to be a major operational problem. the incompatibility between injected and formation waters may result in inorganic scale precipitation in the equipment and reservoir and then reduction of oil production rate and water injection rate. ...

In the present study, small scale effect on critical buckling loads of triangular nano- composite plates under uniform in-plane compression is studied. Since at nano-scale the structure of the plate is discrete, the size dependent nonlocal elasticity theory is employed to develop an equivalent continuum plate model for this nanostructure incorporating the changes in its mechanical behavior. The...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شیراز - دانشکده علوم 1391

in this thesis protic and aprotic ammonium-based ionic liquids were synthesized and their surface tensions were measured in the range of 298-373k. the protics are alkyl ammonium-based ils with the carboxylate (formate, acetate, propionate) anion and aprotics are quaternary ammonium-based ils with bis(trifluoromethylsulfonyl)imide anion. capillary rise method was used for surface tension measure...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده علوم 1391

1. to determine whether difference in birth body mass influenced growth performance in pipistrellus kuhlii we studied a total of 12 captive-born neonates. bats were assigned to two body mass groups: light birth body mass (lbw: 0.89 ± 0.05, n=8) and heavy birth body mass (hbw: 1.35 ± 0.08, n=4). heavier body mass at birth was associated with rapid postnatal growth (body mass and forearm length) ...

Abolhasan Nazarinezhad Giashi, Habib Ramezannezhad Azarboni Reza Ansari,

In this paper, based on the nonlocal Timoshenko beam theory, a nonlinear model is presented for the vibrational behavior of carbon nanotubes (CNTs) embedded in elastic medium in thermal environment. Using the Timoshenko beam theory and nonlocal elasticity of Eringen, the influences of rotary inertia, transverse shear deformation and small scale effect are taken into account. To model the intera...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید