نتایج جستجو برای: Dynamic Dielectric Constant

تعداد نتایج: 645089  

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده علوم 1393

in this thesis, structural, electronical, and optical properties of inverse pervskite(ca3pbo) in cubic phase have been investigated.the calculation have been done based on density functional theory and according to generalized gradiant approximate (gga) as correlating potential. in order to calculate the configurations, implementing in the wien2k code have been used from 2013 version. first of ...

Journal: :مهندسی بیوسیستم ایران 0
محمود سلطانی فیروز کارشناسی ارشد، دانشگاه تهران رضا علیمردانی استاد، دانشگاه تهران محمود امید استاد، دانشگاه تهران

grading of agricultural products has always been a subject of research by scientists. one of the criteria to be chosen for grading of fruits is the fruit's level of ripeness. different methods have been employed to assess the status of fruit ripeness some of which are destructive and others are not so. in this research, a noninvasive capacitive method was used to estimate the ripeness leve...

Journal: :جنگل و فرآورده های چوب 0
کژال مرادیان کارشناس ارشد صنایع خمیر و کاغذ، دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران محمد آزادفلاح استادیار، گروه علوم و صنایع چوب و کاغذ، دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران امیر عباس شایگانی اکمل استادیار، گروه مهندسی برق، دانشکدة مهندسی برق و کامپیوتر، دانشگاه تهران، تهران، ایران علی عبدالخانی دانشیار، گروه علوم و صنایع چوب و کاغذ، دانشکدة منابع طبیعی، دانشگاه تهران، کرج، ایران

the oil-paper insulation is a type of an inexpensive combination insulation system in oil-filled power transformers. in this study the dielectric and strength properties of canola oil and mineral oil impregnated hand-sheet papers were investigated. all hand sheets were made of unbleached bagasse soda pulp with two different freeness levels of 200 ± 25 ml, csf and 400± 25 ml,csf. after drying th...

Journal: :journal of physical & theoretical chemistry 2013
m. aghaie t. jalili

using the mixed solvents, (water +ethanol + propanol), the solubility of cdf2 was determined byevaporating method at 25° c. the results showed that the sollbility, s, of cdf2 decreases bydecreasing the dielectric constant of the mixed solvent .once the solubility of cdf2 was determined,the concentration solubility product, ksp(c)=4s3, was calculated .furthermore ,by estimating the meanactivity ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه ارومیه 1377

the methods which are used to analyze microstrip antennas, are divited into three categories: empirical methods, semi-empirical methods and full-wave analysis. empirical and semi-empirical methods are generally based on some fundamental simplifying assumptions about quality of surface current distribution and substrate thickness. thses simplificatioms cause low accuracy in field evaluation. ful...

Despite the simplicity of the hexagonal graphene structure formed by carbon atoms, the electronic behavior shows fascinating properties, giving high expectation for the possible applications of graphene in the field. The Graphene Nano-Ribbon Field Effect Transistor (GNRFET) is an emerging technology that received much attention in recent years. In this paper, we investigate the device performan...

زرگر شوشتری, مرتضی, سلطانی, میترا, موسوی قهفرخی, سید ابراهیم,

In this paper, the chromium doped spinel zinc ferrite nanoparticles were synthesized by using of glycine as a fuel with microwave combustion method. After preparing the samples  with x = 0.0, 0.5, 1.0, 1.5, 2.0, the electromagnetic and electrical properties such as dielectric constant, ac conductivity, dielectric loss factor (and Curie temperature were investigated. According to the results, in...

Journal: :آب و خاک 0
داوود نامدار خجسته مهدی شرفا محمود فاضلی سنگانی

abstract time domain reflectometry (tdr) is a widely used method for measuring the dielectric constant (ka) and bulk electrical conductivity (σa) in soils. the tdr-measured σa and ka can be used to calculate the soil solution electrical conductivity, (σp). a theoretical model describing a linear relationship between bulk electrical conductivity, σa, and dielectric constant, ka, in moist soil wa...

In this research, BaTiO3 thick deposit has been successfully sprayed by air plasma spray. The microstructure and dielectric properties of thick films were investigated by secondary electron microscopy (SEM) and LCR meter respectively. XRD measurement was carried out on plasma sprayed BaTiO3. The results illustrate differences in the crystal structure between plasma sprayed coatings and feed sto...

Journal: :journal of agricultural science and technology 2010
a. afzal s. f. mousavi m. khadem

water is one of the most vital constituents in plants. in this research, for an estimation of leaf moisture content, the variation of capacitance was employed. the variations were measured via designed and manufactured capacitive sensors. the objective of the research was to estimate leaf moisture content by measuring its capacitance for five agronomic crops. experiments for measuring leaf capa...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید