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...

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...

In livable city streets, the physical and social components should work together to enhance the health and development of the urban community and every individual member of the society. These streets are known as the heart of urban social life, and also as a place for providing social needs of citizens. Due to the essence of modern lifestyle and allocation of larger part of people's time to out...

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...

from 1950s onward, new theories and critical approaches burgeoned across humanities. these theories were context-oriented; as a result, the analysis of discursive practices gained significance. thus, social, political, historical and cultural discourses that have been hitherto marginalized and considered inferior to literary texts, were introduced as important texts to be analyzed by critics. o...

this thesis is an evaluation of poetry of sylvia plath (1932- 1963) and forough farrokhzad (1935-1967) using feminist approach and finds the positive concepts of hope, reason and strength through feminine images in their poetry. plath and farrokhzad are from different cultures and different countries but they share the same concepts and themes in their poetry. by applying feminist theory to the...

 In today's world, the process of globalization and communication and information innovations has brought the "cities" into an actor of national and global competition. No urban point in the world can rely on maintaining its traditional role in the urban hierarchy, as other urban areas compete in a network structure with other cities in order to enhance their position on the network and overcom...