Sharif Digital Repository

nowadays, due to population growth, unconventional use of water resources and on the other hand, climate change, limited renewable water resources, reduction of groundwater cavities, the need for water for agricultural use and energy production are increasing. Due to the fact that each cubic meter of dirty water pollutes 40 to 60 cubic meters of clean water and the entry of polluted effluent into the receiving sources of environmental degradation leads to a lot of wastewater treatment, water consumption management and The development of wastewater treatment processes is also becoming increasingly important. At present, wastewater treatment plants face the challenges of high energy... 

Boric acid (H3BO3) is a weak monobasic acid that exist as a white powder in the standard conditions. In industry, it is used in manufacturing of fiberglas filaments, precious metals soldering and production of flat panel LCD displays. In all of these applications, normal grade boric acid is used, but nuclear industry demands an ultrapure boric acid (UPA) for controlling of the reactivity and power levels in pressurized water reactors. Annual consumption of UPA in Bushehr Power Plant (BPP) is around 60 metric tons. Currently, this amount is imported from Russia, but atomic energy organization of Iran plans to displace it by the acid made inside the country. Domestic production of UPA in... 

Nowadays, intracellular studies have been widely developed in biological applications. Intracellular analysis requires direct experiments on cells such as cell separation, purification, lysis and DNA extraction. The process of cell lysis and the resulting DNA purification is a crucial step in diagnostic processes. Since, the basis of many genetic studies is the information existed in double-stranded DNA structures.In this project, a microfluidic system is presented which performs integrated chemical cell lysis and DNA extraction. The cell used in this study is L-929. In order to increase cell lysis, the serpentine micromixer in combination with internal and external barriers at the beginning... 

In this study a droplet-based microfluidic system is desighned and fabricated to effectiverly lyse MCF7 cells and extract and purify their DNAs. The main purpose of this study is to transfer all the steps from macro scale to a microfluidic system containing a fluidic chip. This system is a semi automatic system and every part of the lysis and purification process is performed in one step. The first step is to encapsulate single cells and multi cells inside the droplets. By controlling the concentration of the cell solution, the number of encapsulated cells inside the droplet is efficiently and easily controlled and the cells were encapsulated as single cells and as multi cells inside the... 

Fresh water has always been one of the basic needs of human. Thus using different methods for water purification becomes more important in recent years. In classic methods such as distillation chamber and thermal method, water flux was always low and salt rejection wasn’t satisfactory. So investigating new methods such as nanofiltration becomes more important. This method has high efficiency and good water flux in compare with old methods. One of the useful materials in nanofiltration is grapheme oxide (GO). GO sheets make an array of nanochannels and this membrane improves filtration and water flux. Different parameters affect water flux and salt rejection in this membrane. Restructuring... 

Gold is a noble and precious metal used in various industries, including jewelry, electrical and electronic, catalyst, and medical industries. Multiple processes are used to extract and refine gold; each one has its advantages and disadvantages. In this research Work, comprehensive information on the electrochemical purification process of gold from anode electrode with 75% crude gold and titanium cathode electrode in the chloride electrolyte solution is presented. To perform the purification process, first using the parameters and their levels, including temperature (30, 45, and 60 degrees Celsius), voltage (2, 2.2, and 2.4 volts), and acid concentration (1, 2, and 3 M), Design of... 

During the past few years, hexavalent chromium (Cr(VI)) is of environmental concern due to its high toxicity and mobility. Therefore, removing it from industrial wastewater is of chief significance. In this research, efficient photocatalyst materials (xµLTiO2NPs@ZIF-8) for the reduction of Cr(VI) from water resources were firstly synthesized. This composite was prepared by an in situ method with zeolitic imidazolate framework-8 as the matrix. TiO2 and ZIF-8 were selected for their excellent stability in aqueous media, high photoactivity, non-toxicity, and high surface area. The structure of the as-synthesized materials was characterized by X-ray powder diffraction (XRD), scanning electron... 

Titanium dioxide is one of the most important first material in many industrial applications and for producing Titanium.Although it was discovered more than 200 years ago and has been commercially processed for 85 years, it is still being actively investigated. So far Iran imports TiO2. But some projects have been planned to produce pure TiO2 from Ilmenite and Titanomagnetite ore. In the present work production of highly purity TiO2 from Ilmenite ore by chloride leaching has been investigated. Chloride leaching has been accomplished by several stages of leaching in hydrochloric acid, reduction, crystallization, hydrolysis and finally calcination of the powder. According to the result... 

In all types of chromatography for the extraction and purification of proteins, a fixed substrate is needed with which the mobile phase containing the proteins interact with them. This fixed bed should contain grains that have characteristics such as sphericity, high surface area, hydrophilicity, binding power to functional groups, chemical stability, low specific absorption, reusability and low cost. Commercially, the most commonly substrates in the ranges of the molecular weight of proteins are agarose and dextran. Agar was extracted from Gracilaria salicornia seaweed and removal of ionic groups was investigated by three methods. In washing with isopropanol, the ionic groups were reduced... 

Triclosan is widely used as an antibacterial agent in personal health care products, especially in recent years with the spread of the Coronavirus. This substance is one of the emerging contaminants, and due to its stable and toxic nature, this material cannot be destroyed in the process of biological wastewater treatment. In this research, a new bacterial strain was isolated and purified from industrial wastewater for the biological removal of triclosan. Based on 16S rRNA sequencing, it was found that the isolated strain belongs to the Enterobacter cloacae family and can grow in high concentrations of triclosan. It was observed that naphthalene dioxygenase and laccase enzymes are active... 

During the past years, microtechnologies have been extensively used in Chemical reactions. In these systems, using an optimal system for separation, and purification of Chemical Products is of great importance. In this study, we have focused on the separation of organic-phase and aqueous-phase Products in 26 fabricated microsystems. The fabrication method of the glass microseparators consists of Lithography, Acidization, and Glass-to-Glass Thermal Connection. We have also studied key parameters of organic and aqueous phase separation in continuous capillary microseparators like the width of the capillary channel, length of the capillary channel, number of the capillary channels, and flow of... 

Air pollution is one of the main environmental problems in Iran's metropolises, especially in the city of Tehran. Taxis have a significant contribution to pollution due to the long distances they travel during the day. Due to the fact that the operation of automotive three-way catalysts is a function of their operating conditions, and considering the different fuel composition in Iran and the specific conditions of engine performance, exhaust gas composition can be different from similar cases abroad. A commercial three-way catalyst was tested to evaluate its performance under conditions relevant to the exhaust gas of Tehran's taxis fleet. In this study, CO and C3H6 were considered as the... 

Photocatalytic degradation is one of the developing modern and effective methods for decontamination of hazardous pollutants of chemical industrial wastewater. In spite of great developments in this field of research and its various advantages, finding a process with high efficiency and optimization of the operating parameters are still required to be investigated. In this study, the photocatalytic degradation of 2-Nitrophenol under natural sunlight irradiation using industrial photocatalysts such as TiO2 (Hombikat), ZnO, WO3 and TiO2 (P25) was investigated. The photocatalysts were characterized by the XRD, BET, SEM and DRS tests and the effects of significant operating parameters (the... 

Cell lysis, as the first procedure of cell pretreatment, is a process that breaks cell membranes open thereby facilitating access to intracellular substances, such as DNA, proteins, and other components for further analysis to diagnose and treat diseases at early stages. Currently, there are several methods for cell lysis at macroscales. However, the time-consuming and expensive procedures as well as the large scal of the system are the main disadvantages of the systems. Recently, microfluidic systems have attracted considerable attention due to advantages associated with automation, integration and miniaturization of biomedical test protocols. Centrifugal microfluidics (Lab-on-a-Disc) is a... 

Enzymes, which are biochemical catalysts, have important applications in different industries such as food, pharmaceutical, medical, chemical identification and etc. Several methods have been used for separation of enzymes among which precipitation, chromatography and two-phase system. In this work, purification of α-amylase has been done by Ammonium Sulfate and Acetone precipitation, gel filtration based on Sephadex, and PEG-salt aqueous two-phase system. Furthermore, mass and momentum conservations’ equations were solved simultaneously to simulate the process based on the finite element method (FEM). Crude enzyme was precipitated with different saturations of ammonium sulfate and the... 

Increased photo catalytic activity of NiO and 〖Co〗_3 O_4 were obtained by Ni〖Co〗_2 O_4 synthesizing and supporting functionalized multiwall carbon nano-tubes via calcinations followed by hydrothermal precipitation. NiO, 〖Co〗_3 O_4 and Ni〖Co〗_2 O_4 were prepared in the same procedure exactly for the subsequent photo catalytic activity to be compared to Ni〖Co〗_2 O_4/MWCNT later on. The photo catalytic degradation of Reactive Red 120 dye as a deazo organic pollutant model was used for experimental photo catalytic performance analysis. The CCD method was applied for experimental designing, modeling, and optimizing the operational parameters of the photo catalytic degradation of RR120 using... 

Conjugated linoleic acid (CLA), a mixture of positional and geometrical isomers of linoleic acid with conjugated double bonds, has gained considerable attention because of its anticarcinogenic and obesity treatment properties. The most biologically active CLA isomers are 9c, 11t-18:2 and 10t, 12c-18:2. The aim of this study is to separate and purify the two essential isomers via enzymatic method by Candida rugosa lipase and chemical method by urea crystallization and also optimization of reaction conditions in order to better separation. For enzymatic purification, L-menthol and Lauryl alcohol were used separately. Optimization of reaction conditions by enzyme content, time and the ratio of... 

Conjugated linoleic acid (CLA), a mixture of positional and geometrical isomers of linoleic acid with conjugated double bonds, has gained considerable attention because of its anticarcinogenic and obesity treatment properties. The most biologically active CLA isomers are 9c, 11t-18:2 and 10t, 12c-18:2. Natural sources of CLA are fat of meat and dairy products derived from ruminant animals. About 3 grams of CLA per day is necessary to provide human health needs, but each person receives about 10% of this value from natural resources, thus production of CLA as a dietary supplement is necessary. CLA is produced from biological and chemical methods but because of high yield of chemical... 

Photocatalytic degradation is one of the developing modern and effective methods for decontamination of hazardous pollutants of chemical industrial wastewater. For this purpose, in this research, the efficiency of the photocatalytic process in degradation of Cortisone Acetate is investigated under solar light irradiation, and the effect of two useful oxidants, potassium persulfate (PDS) and potassium proxy mono sulfate (PMS), on the degradation efficiency is examined. At first, the single effect of these two oxidants, and then their interaction effects with the photocatalyst (TiO2-P25) and solution pH by analytical analysis and with the help of Response Surface Methodology (RSM) and... 

This project related to gas purification according to difference in the deposition point in the fludized bed.The main reason for choosing fluidized bed is increasing overall heat transfer coefficient compare in to other heat exchangers. Separation process, by cooling the wall causes the self- deposition gas phase shifts to solid phase. Solid formed on the wall, act as an insulating layer and greatly reduces the heat transfer. To solve this problem, the fluidized bed system is offered because fluid particles in addition to remove the insulating layer, improving convection heat transfer coefficient . Laboratory tests show the feasibility of preventing the formation of insulating layer by...