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In recent decades, due to economic, political and environmental issues, tend to use of the CHP systems (combined heating and power) have increased. CHP systems not only increase energy efficiency, but also decrease fuel consumption and emission levels of systems. The use of CHP technology in the industry has a long history, but the use of these systems in the commercial and residential sector, is considered, recently. As to the residential buildings, both electricity and thermal energy demands fluctuate seasonally and hourly, so it is necessary to take account of the plant’s annual operational strategies for the variations of load demands. In this paper, a nonlinear programming model is... 

The question of the time is one of the obscure and challenging subjects which has been discussed as a mysterious problem in various civilizations. In ancient Greece, the question has been debated among the supporters of existence and eternity. We observe the words of Plato, on the existence of the absolute essence of eternity against the change and transition time instantiated as a conducted river in the Heraclitus view. Other discussions focused on the relationship between the change and displacement, or the the spatial relations to which Aristotle paid attention. With the passing of time from the ancient and medieval eras to the Renaissance period, along with the growth of the science in... 

With the popular choice of using underground structures and tunnel in big cities and with significant damage in recent large earthquake; therefore more attention is given to the behavior of the underground structure in seismic area. The purpose of this thesis is to present the Soil-Tunnel-Structure Interaction analysis performed for different dynamic load condition. Therefore we modeled a 3D intersection part of two different tunnels in homogeneous soil by ABAQUS software. The soil and concrete structure of tunnel is modeled by three dimensional solid finite elements and the boundary of soil is modeled by three dimensional infinite elements with 8 nodes. The results demonstrate the geostatic... 

A brief overview of the proposed research, its aims, engineering relevance and applications Underground space has long been exploited through the history to fulfill different human necessities. Underground facilities built in areas subject to earthquake activity must withstand both seismic and static loads. Some underground structures have experienced significant damage in recent large earthquakes. Tehran is located in seismic zone and investigation and research on the subject has significant role in design and construction of underground spaces for earthquake loads. Underground structures are complex structures which consist of different parts Such as passage way and platform space. Passage... 

The aim of this project was to upgrade and reduce viscosity of heavy oils by adsorbing of asphaltene on Ni-Mo/CB and converting it into lighter and more valuable gas and liquid compounds. Asphaltene has been extracted from a heavy crude oil sample of Soroush oil field in Iran. After adsorption, Asphaltene conversion to lighter components (gas/liquid) was studied through hydrocracking process. To prepare the support of catalyst, Carbon Black, initially a thermal treatment step under the argon gas atmosphere followed by acid-washing process was performed. Afterward, the catalysts was prepared through dry impregnation method. In order to activate catalyst for hydrocracking, the catalysts has... 

The parasite entering into the blood of a malaria infected individual eventually causes the formation of gametocytes inside the blood cells. With the insect bite, the male and female gametes will enter the insect's stomach and form the zygote. After developing in the stomach, the zygote first turns into an ookinete and then into an oocyst, and by passing through the stomach wall and tearing the sporozoites, it enters the salivary glands of the insect, and if another person is bitten by that insect, the parasite enters the body of that person. and this cycle continues between the insect and the human body. Stopping this cycle requires blocking one part of this cycle. Studies show that... 

Transition metal oxides and carbon based materials (especially graphene) are common electrode materials in supercapacitors. The metal oxide limitation is due to their high agglomeration and low electrical conductivity. On the other hand graphene base materials due to their unique structure as well as high electrical conductivity and high surface area increase energy storage capability. However, chemically produced graphene generally suffers from high agglomeration and re-stacking after removal from the solution and drying, g, which results in reduced electrochemical performance of graphene sheets in supercapacitors. To take full advantage of these two groups of materials, it is expected that...