Sharif Digital Repository

In textile industry, advanced oxidation processes are used for degrading and removing color from dye baths which allow wastewater reuse. In this study, photochemical oxidation processes (UV-A/K2S2O8, UV-C/ K2S2O8) and chemical oxidation process (dark/K2S2O8), were investigated in a laboratory scale photoreactor for decolorization of the Reactive blue 19 (RB19) dye from synthetic textile wastewater. The effects of operating parameters such as potassium persulphate dosage, pH, reaction time and UV source, on decolorization have been evaluated. The results of direct chemical oxidation showed that 50% of the dye was been removed using K2S2O8 in dark condition after 5h reaction time and... 

Dyestuffs removal from industrial wastewater requires special advanced technologies, since dyes are usually difficult to remove by biological methods. In this study nanofiltration process was used for removal of different dyestuffs from solutions. The rate of dye removal by spiral wound nanofiltration membrane in film thin composite MWCO=90 Dalton, was evaluated for four classes of dyes acidic, disperse, reactive and direct in red and blue dyes medium. Dye absorbance was measured by spectrophotometric method (2120 Standard Method 1998). Effects of feed concentration, pressure and total dissolved solids concentration were also studied. Results showed that increasing dye concentration lead to... 

In recent years there has been potential increase in the use of alkaline protease as industrial catalysts. Many major industrial and commercial applications, such as food and textile industries, and medical diagnoses, are highly dependent on the protease enzyme. In the cell immobilization technique, the free movement of microorganisms is restricted in the process, and a continuous system of fermentation can be used. In the present work, this technique has been used for alkaline protease production using different carriers, such as chitosan, corn cob and corn tassel. Enzyme activity before immobilization (72 h) was 78.3 U/ml. Corn cob, with 65% immobilization capacity and the highest enzyme... 

Low temperature plasma (LTP) is nowadays an intensively investigated superficial treatment of wool. In this work we have investigated the effect of LTP on wool fabric under different conditions. The effect of the position of samples inside the reactor and the kind of gases used as discharge medium has been also investigated. The results show that not only the topography of the surface is modified but also the chemical composition of the surface. It is shown that the hydrophilicity of the samples and also their shrink resistance and anti-felting behavior have improved significantly under LTP treatment. The results show that the shrinkage of 30.1% for untreated samples has reduced to about... 

In this paper a reliability, emission, and network security constrained unit commitment (UC) with the focus on wind power integration is formulated. It is shown that clearing both energy and spinning reserve markets taking into account network constraints provides a reliable and economic solution for day-ahead operation planning of a power system with a significant amount of thermal and wind power in the generation portfolio. The developed UC is formulated and implemented in MATLAB. The IEEE 24-Bus Reliability Test System (RTS) is used to verify the UC method by simulation. © 2017 IEEE  

Various challenging pollutants are produced in the environment by organic materials of diverse industries including leather, paint, and textile. Nowadays, it is vital to develop efficient manners regarding the fundamental issues and removing pollutants. Such pollutants can be effectively removed from the environment through heterogeneous catalysts. Recently, a huge deal of interest has been attracted by hydrogel-based metal catalysts as heterogeneous and efficient catalysts. In this regard, silver with its unique features is suitable for environmental remediation. Hence, the present review deals with summarizing the present advances in the synthesis of silver-based hydrogel catalysts, as... 

Cotton fabrics have been prepared with smart properties by functional finishing with stimuli-responsive nano gel. A biopolymer (chitosan) and a synthetic polymer (poly-NiPAAm) have been used for the synthesis of nano gel through semi-batch surfactant-free dispersion polymerization (SB-SFDP) method. The incorporation of nano gel to textile fabrics is achieved by pad-dry-cure procedure, using an aqueous nano gel dispersion and 1,2,3,4-butantetracarboxylic acid as a crosslinking agent. With this cross linking method, it is possible to integrate the nano gel into the cotton fabric’s structure with good resistance to washing. The changes in physiological comfort parameters of cotton fabric such... 

In recent years, much attention has been given to monitoring multistage processes in order to effectively improve the product reliability. To this end, the output of the process is investigated under special circumstances, and the values corresponding to reliability-related quality characteristic are measured. However, analyzing reliability data is quite complicated because of their unique features such as being censored and obeying nonnormal distributions. A more sophisticated picture arises when the observations of the process are autocorrelated in some cases, which makes the application of previous control procedures futile. In this paper, the accelerated failure time (AFT) regression... 

The presence of dyes as pollutants in wastewater sources from textile industries can cause significant health issues if they are not adequately treated. Dye adsorption to entrap contaminants in nanoparticle pores has created considerable attention in recent years due to the environmental concerns occurring as a result of spillage of dyes in water bodies. In efforts to understand adsorption capability UiO-66, metal-organic frameworks (MOFs) were developed and examined for the separation of four pollutant dyes containing methyl red (MR), methyl orange (MO), malachite green (MG), and methylene blue (MB), which are widely used in textile industries. The adsorbent structural stability in water,... 

Laminated polymer-steel composites are promising layered materials for practical applications in the automotive industry considering their superior crush resistance capacity in terms of enhanced damping potential. In this research, the sheet lamination (SL) route of friction stir additive manufacturing (FTAM) technology was implemented for the production of a poly-methyl-methacrylate (PMMA) polymer matrix composite structure as reinforced by textile stainless steel layers, and feeding of PMMA granulates inside the stirred region. Layers bonding and the soundness of composite formation during fabrication of the laminated structure were studied. Possible chemical interactions between the steel... 

The photocatalytic degradation of Reactive Blue 19 (RB19) dye has been studied using TiO2 nanofibre as the photocatalyst in aqueous solution under UV irradiation. Titanium dioxide nanofibre was prepared using a templating method with tetraisopropylorthotitanate as a precursor. The experiments were carried out in the presence of the TiO2 nanofibre, and the effects of pH and electron acceptors on the degradation process were investigated. In order to observe the quality of the aqueous solution, chemical oxygen demand (COD) measurements were also carried out before and after the treatments. The photocatalytic decomposition of RB19 was most efficient in acidic solution. With the addition of...