bekenstein and hawking by introducing temperature and every black hole has entropy and using the first law of thermodynamic for black holes showed that this entropy changes with the event horizon surface. bekenstein and hawking entropy equation is valid for the black holes obeying einstein general relativity theory. however, from one side einstein relativity in some cases fails to explain expe...

this thesis attempts to measure learning styles, self efficacy and intrinsic motivation as predictors of iranian ielts reading comprehension. in order to address this issue, a quantitative study was conducted on some randomly selected intact students at ferdowsi university. these two groups were assigned as they were undergraduate (ba=91) and graduate (ma =74) students; they were all aged betwe...

‏‎the community dynamics of aquatic coleoptera(insecta)in one of the spring-stream habitats of bammo national park in fars province called cheshmeh-ye-ghanbari is studied as a pilot project and model for acquaintance with and furthering the biodiversity studies on fauna of iran. sixteen species-populations out of nineteen of this community were already identified for their taxonomy and for thei...

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 ...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

abstract in first part of this project, the use of a new and biguanid-like catalyst supported on silica as a recyclable catalyst provides a new route for the synthesis of a variety of arylalkylidene rhodanine derivatives through knoevenagle reaction in at present of solvent at room temperature. rhodanine derivatives and especially arylalkylidene rhodanines have proven to be attractive compound...

asymmetric membranes are widely used in many industrial membrane separation processes. the major advantage of membrane filtration over the conventional process is its ability to remove a wider spectrum of particles without using any chemicals. hollow fiber configuration offer many advantages over flat-sheet or tubular membranes. the spinning process of hollow fiber may look simple, yet it is te...

this thesis basically deals with the well-known notion of the bear-invariant of groups, which is the generalization of the schur multiplier of groups. in chapter two, section 2.1, we present an explicit formula for the bear-invariant of a direct product of cyclic groups with respect to nc, c>1. also in section 2.2, we caculate the baer-invatiant of a nilpotent product of cyclic groups wuth resp...

چکیده: در این تحقیق تأثیر ملاس که یکی از محصولات جانبی صنایع قند می باشد به عنوان یک افزودنی مقاومت خشک جدید در بهبود پالایش پذیری و ویژگی های فیزیکی و مکانیکی مقوای کنگره ای کهنه (occ) مورد بررسی قرار گرفته شد. بدین منظور پنج سطح ملاس( 0،5، 10، 15 و 18%) و سه سطح درجه روانی(420،400و320 میلی لیتر)به عنوان فاکتورهای متغیر در نظر گرفته شد و برای هر تیمار کاغذهای دست ساز با مساحت 2cm200 و وزن پای...

in this thesis, barium ferrite nano particles were prepared by sol-gel method. their structural and magnetic properties of samples have been investigated using thermo gravimetric analysis (tg-dta), x-ray powder diffractometer (xrd), fourier transform infrared (ftir), scanning electron microscopy (sem), field emission scanning electron microscopy (fesem), ac susceptometer, vibrating sample magne...