introduction acetic acid bacteria are large group of obligate aerobic gram negative bacteria with the ability to oxidize ethanol to acetic acid (1). they are widely distributed in natural habitats and classified in family acetobacteraceae. members of this family are useful in industrial production of vinegar(2). acetic acid bacteria (aab) can use substrates as glucose, ethanol, lactate or glyc...

throughout this dissertation r is a commutative ring with identity and m is a unitary r-module. in this dissertation we investigate submodules of multiplication , prufer and dedekind modules. we also stat the equivalent conditions for which is ring , wher l is a submodule of afaithful multiplication prufer module. we introduce the concept of integrally closed modules and show that faithful mu...

in this thesis, we exploit a simple and suitable method for immobilization of copper(ii) complex of 4?-phenyl-terpyridine on activated multi-walled carbon nanotubes [amwcnts-o-cu(ii)-phtpy]. this nanostructure was characterized by various physico-chemical techniques. to ensure the efficiency and fidelity of copper species, the implementation of three-component strategies in click-chemistry all...

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...

بررسی تنوع ژنتیکی ژنوتیپ‏های بومی پیاز ایرانی در مقایسه با انواع خارجی چکیده: برنامه های اصلاحی گیاهان بر اساس تنوع و انتخاب صفات برتر کمی و کیفی صورت می گیرد. لذا، ارزیابی تنوع ژنتیکی، اولین مرحله در برنامه های اصلاحی است. در این راستا، استفاده از روش های جدید مطالعه‏ی تنوع ژنتیکی ضروری به نظر می رسد. در این بررسی تعیین تنوع ژنتیکی سیزده ژنوتیپ پیاز ایرانی در مقایسه با دو ژنوتیپ خارجی با است...

the main purpose of this study was to investigate any relationship between high school efl teachers metaphorical understandings of their role in class and their self-efficacy beliefs. teachers metaphors were elicited through two different prompts: one picturing what they believed a language teacher should be like in class, and the other demonstrating what they are actually like in class; such...

abstract: one of the most visited & important spaces in different countries by tourist are urban areas. the old tehran which major part is located in district 12 is historical showcase of the capital, but, its hiidden cultural attraction is not used as it should be. this thesis occasionally engage in studying the efficacy of correct installation of travel guide boards in welfare & easily acc...

abstract: the present study was undertaken to investigate whether 1) there is any significant correlation between iranian efl/eap learners’ l2 writing proficiency and their willingness to communicate, 2) there is any significant difference between efl and eap learners in terms of willingness to communicate, 3) there is any significant difference in wtc of iranian efl/eap learners with 1- nati...

abstract amino acids are building blocks of proteins, and play a vital role in living beings existence and their functionality. the interaction of these compounds with metal ions is of great importance to biochemists, and chemists, because their functions can be utilized as a model in understanding enzymes mechanism for transport of metal ions to tissues. among twenty essential amino acids w...