1- in a search directed to the reaction of compound)23(the cycloaddition reaction of 1,3- diphenylisobenzofurane)14(with p-benzoquinone)19(,followed by addition of cyclopentadiene was carried out.the specific spacial stracture of its ir,nmr,mass spectra. 2- in another attempt the kinetic stability and behavior of compounds)20(and)23(was studied.the main subject of this study was the highly reve...

abstract the third millennium has started, but the world is facing with serious challenges in achieving international security and peace. various human rights violations have lead the states to find means to protect human rights. also article 55 of the united nations charter introduces the respect to human rights and fundamental freedom as the most suitable ways to realize peace and security. ...

a professional is someone whose work involves performing a certain function with some degree of expertise. but a narrower definition limits the term to apply to people such as teachers and doctors, whose expertise involves not only skill and knowledge but also the exercise of highly sophisticated judgment, and whose accreditation necessitates extensive study, often university-based as well as p...

in this thesis, a better reaction conditions for the synthesis of spirobarbiturates catalyzed by task-specific ionic liquid (2-hydroxy-n-(2-hydroxyethyl)-n,n-dimethylethanaminium formate), calcium hypochlorite ca(ocl)2 or n-bromosuccinimide (nbs) in the presence of water at room temperature by ultrasonic technique is provided. the design and synthesis of spirocycles is a challenging task becaus...

fluorescence chemical sensors for the highly sensitive and selective determination of pb2+ , hg2+, co2+ and fe3+ ions in aqueous solutions are described. the ion sensing system was prepared by incorporating lipophilic ligand (l) as a neutral ion-selective fluoroionophore in the plasticized pvc membrane containing sodium tetraphenylborate or potasium tetrakis (p-chlorophenyl) borate as a liphoph...

to explore the idea the investingation proposed, aimed at finding whether the performances of the population of iranians students studying english in an efl context are consistent in l1 and l2 writing taks and whether there is a cross-linguistic transfer in this respect. in this regard the subjects were instructed to write four compositions-two in english and two in farsi-which consisted of an ...

wireless sensor networks (wsns) are one of the most interesting consequences of innovations in different areas of technology including wireless and mobile communications, networking, and sensor design. these networks are considered as a class of wireless networks which are constructed by a set of sensors. a large number of applications have been proposed for wsns. besides having numerous applic...

there are two major theories of measurement in psychometrics: classical test theory (ctt) and item-response theory (irt). despite its widespread and long use, ctt has a number of shortcomings, which make it problematic to be used for practical and theoretical purposes. irt tries to solve these shortcomings, and provide better and more dependable answers. one of the applications of irt is the as...

due to the limiting workspace of parallel manipulator and regarding to finding the trajectory planning of singularity free at workspace is difficult, so finding a best solution that can develop a technique to determine the singularity-free zones in the workspace of parallel manipulators is highly important. in this thesis a simple and new technique are presented to determine the maximal singula...

supervisors play an undeniable role in training teachers, before starting their professional experience by preparing them, at the initial years of their teaching by checking their work within the proper framework, and later on during their teaching by assessing their progress. but surprisingly, exploring their attributes, professional demands, and qualifications has remained a neglected theme i...