Sharif Digital Repository

Today, presence of micropollutants, including pharmaceutical compounds, in aquatic systems has turned into a major environmental challenge threatening the health of humans and many aquatic and terrestrial organisms. In the recent years, biodegradation of pharmaceuticals using enzymes, such as laccase, has been presented as a green method for eliminating these types of pollutants. Furthermore, regarding the improved stability and reusability of immobilized enzymes, these types of biocatalysts are suitable for industrial applications. Enzymatic membrane reactor is a promising method of enzymatic treatment and fabrication of a high-efficiency enzymatic membrane is a major step to begin this... 

Resin Transfer Molding (RTM) which is one of the categories of Liquid Composite Molding (LCM) process, is considered as one of the most important process in polymer composite manufacturing. To improve this manufacturing method and reaching higher qualities, numerous modified methods has been developed. One of these modified methods is Vaccum Assisted Resin Trasnfer Molding with Flexible Tooling which is considerably applicable in manufacturing parts with high quality, large and complex geometry. Although, this manufacturing method has variety of advantages, there are some problems such as void formation making production difficult and dependent to experimental trial and error. So numerical... 

In this study composite is built based on epoxy which is reinforced with 3D graphen foam using the RTM (resin transfer molding) method in which the molding is done by hand, through injecting epoxy to graphen foam.Good scattering and neat meshing of 3d graphen planes in composite have resulted in its improved mechanical quilities.The subject of the present study is the synthesis of graphen foam from graphen oxide and making graphen foam/epoxy composite in order to improve its mechanical properties. In order to do that, firstly graphen foam is forged from graphen oxide in a 3d mesh, in a way that single graphen planes in polymer matrixes are eliminated.Having very little density, very high... 

The use of polymers is increasing day by day due to low density, reasonable price and ability to produce different products. On the other hand, the accumulation of polymer wastes in nature is one of the environmental concerns in today's world, which is mainly due to the widespread use of polymers in the packaging industry and disposable applications. In order to solve this problem, recycling is recommended as the most appropriate and economical solution. Because in addition to consuming polymer waste, it also saves energy and reduces carbon footprint.Polyethylene terephthalate (PET) is one of the polymeric materials which; It has a special place in the packaging industry and is widely used... 

The aim of this dissertation is to analyze the tensile-stress fatigue of composite rods made of a combination of carbon-epoxy resin as well as carbon chopped-phenolic resin and to investigate the effect of different parameters on their fatigue life. The curing process is completely different in carbon / epoxy and carbon / phenolic composites, Carbon / Epoxy is a thermo-plastic composite, but carbon / phenolic is a thermo- set composite. Therefore, differences in the curing process, raw materials, changes in the volume percentage of resin and fibers, the effects of different loading during the production and curing process of the composite, cooling and heating rates during production can... 

One of the major environmental problems in recent years is the presence of micropollutants that cause many problems for the environment and living organisms. The micropollutant bisphenol A and the drug diclofenac are one of the pollutants and endocrine disruptors. Usually, conventional biological and physico-chemical methods do not have a high ability to remove such pollutants. Also, advanced oxidation methods usually lead to the production of highly toxic products. Using enzymes is an attractive method to remove these micropollutants. Laccase enzyme is one of the most famous enzymes in the field of biotherapy because it can remove a wider range of pollutants and it is one of the... 

Nowadays, micropollutants present in aquatic environments posses a significant threat to the well-being and health of human beings. Various physicochemical and advanced approaches have been proposed to confront these hazards. In recent years, biological treatment methods have gained great interest for their green approach. One of these biological treatment options is the treatment of polluted waters by enzymes. Enzymatic treatment of micropollutants can be achieved by oxidoreductase enzymes. One of the most important and widely used oxidoreductase enzymes employed for water treatment is Laccase. However, enzyme immobilization is employed to counter the drawbacks of using enzymes, such as... 

Implant primary stability is a crucial component of implant survival. Primary mechanical stability is correlated with implant type, surgical technique, quantity and quality of bone at the recipient site. Since bone integration (BI) significance has been acknowledged, a variety of techniques have been developed to quicken BI and achieve faster fixation. Studies have shown that material type, and many surface properties, including as surface composition, roughness, topography, and energy, have a significant influence during the early stages of bone integration to the implant. In this work, we did synthesis one-dimensional nanoneedle-like arrays of hydroxyapatite using the injection method... 

In this research, a new method is proposed for constructing concrete structures with complex geometry, including topology-optimized concrete dams on a small scale. According to global statistics, concrete is the most consumed material in the world after water, and its production process causes a lot of damage to the environment. One of the best ways to reduce concrete consumption is to use tools such as topology optimization to design concrete structures. Nevertheless, few research has been done in the field of topology optimization of concrete dams, one of the important reasons for which is the difficulty of building physical model to perform physical tests, validating numerical models, and...