نتایج جستجو برای: the surface area decreases x

تعداد نتایج: 16289058  

پایان نامه :وزارت علوم، تحقیقات و فناوری - پژوهشگاه مواد و انرژی - پژوهشکده سرامیک 1392

thermal barrier coatings (tbcs) are used to provide thermal insulation to the hot section components of gas turbines in order to enhance the operating temperature and turbine efficiency. hot corrosion and thermal shocks are the main destructive factors in tbcs which comes as a result of oxygen and molten salt diffusion into the coating. in this thesis atmospheric plasma spraying was used to dep...

Amir Hossein Masoomparast Hamid Khorsand Nasim Kiayee

In this study chemical method of dissolution-Precipitation was applied to produce amorphous silica nanoparticles from rice straw ash (RSA), the waste material of rice cultivation. The morphology, particle size, structure and area of specific surface of synthesized amorphous silica nanoparticles were evaluated using transmission electron microscopy (TEM), X-ray diffraction analysis (XRD) and BET...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تحصیلات تکمیلی علوم پایه زنجان - دانشکده فیزیک 1392

in the first part of this thesis we explored wetting and its dynamics for small droplets. first, we showed how a simple feature of water droplets on a surface, i.e. laplace pressure, can be exploited to build a micropump. we investigated capillary pumping in microchannels both experimentally and numerically. putting two droplets of different sizes at the in/outlet of a microchannel, will ge...

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده زبانهای خارجی 1392

this study focuses on tracing the clearly defined elements of magic realism in toni morrison’s song of solomon as an illustrious african american example of the mode. magic realism is a fictional technique that combines fantasy with raw physical reality in a search for truth beyond that available from the surface of everyday life. toni morrison, as a distinguished african-american practitioner ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده علوم 1392

a novel acrylic acid-functionalized fe3o4 magnetic nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperacid in chemical transformations. the structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (tem), thermogravimetric analysis (tga), and ft-ir...

دادمهر, وحید, صائب, فاطمه, نظرزاده, مریم,

We have investigated hall effect on YBa2Cu3-xMxO7-δ (M=Ni, Fe) bulk samples, with dopant amount 0 ≤ x ≤ 0.045 for Ni and 0 ≤ x ≤ 0.03 for Fe, with magnetic field (H=2.52, 4.61, 6.27 kOe) perpendicular to sample’s surface with constant current 100 mA. Our study shows that as both dopants increases, TC decreases and it decreases faster by Ni . In these ranges of dopant and magnetic field the Hall...

Natural convection heat transfer was investigated experimentally in a concentric-cylinders annulus. To enhance the rate of heat transfer, pin fins were installed on the surface of the inner cylinder. Two fin arrangements were employed, namely, staggered and in-line arrangements. The length of the fins varied from 2 to 8 cm and the Rayleigh number Ra changed in the range from 5 x 105  to 5 x 106...

The performance of LaMnxNi1-xO3±δ perovskite mixed oxides (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, 1) which were prepared by different methods, the Pechini and sol-gel methods in the oxidation of greenhouse gases, CH4 and CO, has been investigated. All samples were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electr...

In this study, two new Ni/La-Al2O3 catalysts were prepared by a sol-gel method, with different aluminium precursors (aluminium triisopropoxide and aluminium nitrate). The catalysts were characterized by scanning electron microscope (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), BET specific surface area, and particle size analysis (PSA) techniques. The BET results showed that the par...

Ebrahim Babaei Nader Rostameizadeh

In this study simple catalytic test experiment was performed in a flask of rotary evaporator for dechlorination of nitrochlorobenzene (NCB) over two samples of Ni/LaAl2 O3 nanocatalysts (C1 and C2). In the reaction, Ni acts as a catalyst to collect hydrogen gas in aqueous solution and dissociate it to produce active hydrogen atoms for replacing the chlorine. The catalysts were characterized by ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید