Sharif Digital Repository

The removal performance of total poly phenols and orthodiphenols (o-diphenols) content in olive mill waste (OMW) was investigated with a three stages cross flow laboratory scale rotating biological contactor (RBC) in the present study. Due to high COD and other pollutant existed in the original OMW, before biological treatment of OMW by the RBC system, physico-chemical treatment was effected for COD and other pollutant reduction. Inoculation of RBC was effected by sludge from olive oil factory, and microbial acclimation was continued to 49 days and the system was adapted to about 300ppm of OMW poly phenols and o-diphenols. In biological treatment, effect of operating parameters such as... 

The removal performance of total poly phenols and orthodiphenols (o-diphenols) content in olive mill waste (OMW) was investigated with a three stages cross flow laboratory scale rotating biological contactor (RBC) in the present study. Due to high COD and other pollutant in the original OMW, physico-chemical treatment was effected for COD and other pollutant reduction prior to biological treatment of OMW by the RBC system. Inoculation of RBC was effected by sludge from olive oil factory. In biological treatment, effect of operating parameters such as hydraulic loading (HL) and influent COD were examined. The study of the physicochemical treatment before biological treatment of OMW showed,... 

A laboratory scale study using a modified rotating biological contactor (RBC) was constructed to assess aerobic treatment of toluene, a typical aromatic hydrocarbon. The RBC consisted of 72 parallel discs rotating in a reservoir and was arranged in three stages, i.e. 24 discs oriented in each stage. An artificial wastewater containing toluene was fed to the RBC, inoculated with an enriched culture from petrochemical sewage. The rotation of the discs and the recycling time ensured good mixing of the bulk liquid and resulted in a regular biofilm thickness. Toluene removal was measured by COD measurement and GC. The effect of initial toluene concentration on toluene biodegradation showed a zero... 

In this paper, controlling microbial degradation of water based metalworking system fluid, emulsion oil, is investigated using glutaraldehyde as biocide. Microbial population was determined through colony counting method. Evaluation and results demonstrate that a 15 day treatment by glutaraldehyde results in higher resistance to microbial deterioration. Analysis of variance through multiple comparison tests was conducted and Least Significant Difference (LSD) was determined. An overall observed paired difference between the first and second treatment is significant; therefore, the first treatment, with an addition of glutaraldehyde every 15 days is suggested  

Background: In the recent study, optimum operational conditions of cathode compartment of microbial fuel cell were determined by using Response Surface Methodology (RSM) with a central composite design to maximize power density and COD removal. Methods: The interactive effects of parameters such as, pH, buffer concentration and ionic strength on power density and COD removal were evaluated in two-chamber microbial batch-mode fuel cell. Results: Power density and COD removal for optimal conditions (pH of 6.75, buffer concentration of 0.177 M and ionic strength of cathode chamber of 4.69 mM) improve by 17 and 5%, respectively, in comparison with normal conditions (pH of 7, buffer concentration... 

Doxorubicin-loaded nanocarriers were produced employing folate-modified polyethylene glycol (PEG)-functionalized gold nanoparticles for targeted delivery to positive folate-receptor cancer cells. Doxorubicin and folate were, respectively, conjugated to activated-folate and activated-PEG. The conjugates formed doxorubicin nanocarrier with an average size of 12 nm in diameter. The drug release response of functionalized gold nanoparticles was characterized by an initial rapid drug release followed by a controlled release. The doxorubicin nanocarriers showed higher cytotoxic effect on folate-receptor-positive cells (KB cells) than folatereceptor-negative cells (A549 cells). Cell viability in... 

Partial purification of plant peroxidase from turnip (Brassica rapa) was optimized. Aqueous two phase system and precipitation by ammonium sulfate (as two parallel purification methods) were used. Polyethylene glycol/ammonium sulfate/NaCl (25:7:3%, w/v) system followed by gel-filtration chromatography gave a purification factor of about 36 fold. On the other hand, ammonium sulfate precipitation (60-80% deg) followed by gel filtration gave only about 13 purification fold. Hence, the aqueous two-phase system was more efficient and useful method as a primary purification step since it was less laborious, less time-consuming, and led to more purification factor. The partially purified turnip... 

In this study, synthesis of conductive metal nanowires by using aligned and immobilised DNA strand on solid substrate is reported. The nanoporous gold film was prepared by electrostatic self assembly of gold nanoparticles capped with tryptophan. Tryptophan would improve surface properties of gold nanoparticles for strongly attaching to DNA. Fourier transform infrared (FTIR) spectroscopy confirmed that gold nanoparticles have been capped by tryptophan. Also measured zeta potential shows that there are positive charges on the surface of gold nanoparticles. Investigations by AFM observati on substantially confirm that tryptophan-capped gold nanoparticles can be bonded to DNA template... 

Horseradish peroxidase was encapsulated in calcium alginate for the purpose of phenol removal. Upon immobilization, pH profile of enzyme activity changes as it shows higher value at basic and acidic solution. Investigation into time course of phenol removal for both encapsulated and free enzyme showed that encapsulated enzyme had nearly similar efficiency in comparison with the same concentration of free enzyme; however the capsules were reusable up to four cycles without any changes in their retention activity  

Background: Cancer is the first cause of death in developed countries. The heterogeneous nature of cancer requires patient-specified treatment plans. One reliable approach is collecting Circulating Tumour Cells (CTCs) and using them for prognosis and drug response assessment purposes. CTCs are rare and their separation from normal cell requires high-accuracy methods. Methods: A microfluidic cell capture device to separate CTCs from peripheral blood is presented in this study. The CTC separation device applies hydrodynamic forces to categorize cells according to their sizes. The proposed device is designed and evaluated by numerical simulations and validated experimentally. The simulation... 

This study presents the removal performance of phenol in a three-stages cross flow laboratory-scale rotating biological contactor (RBC). The impact of major process and operating variables, such as input hydraulic loading (HL), input COD loading, and temperature of wastewater on the total removal efficiency of the system were examined. It was observed that the phenol removal performance worsened when the HL increased, and optimum total phenol removal efficiency of 99.9% was observed at loading of 4 × 10-3 m-3 m-2 per day and COD concentration of 800 mg dm-3. On the basis of overall treatment of phenol containing wastewater in the RBC, the optimal removal performance was noted at the end of... 

The purpose of this study was to investigate the use of a horizontal packed bed bioreactor, named Biopack, to treat high strength wastewater, such as bakers yeast wastewater. The Biopack system (RBCP) is a modified rotating biological contactor and the system was applied for secondary treatment. The RBCP system produced high treatment efficiencies, COD removal was 94.9% when COD was 472 mg/l and surface organic loading = 0.187 kg COD/m2 per day and surface hydraulic loading = 6 l/m2 per day. Variations of surface hydraulic loading from 6 to 11.9 l/m2 per day produced a decrease in COD removal efficiency from 94.9 to 58.6%. Other factors, such as shock load, retention time and rotational... 

In this paper the effect of the COD/SO4 ratio on the performance of an anaerobic baffled reactor (ABR) was investigated. Synthetic wastewater (3000 mg-COD/l) was used as the sole organic substrate. ABR was maintained at a hydraulic retention time (HRT) of 1 day and at a temperature of 35 °C. The results of this study showed that when COD/SO4 ratios were changed from 16.7 to 6 with increasing sulfate concentration from 180 to 500 mg/l, COD conversion was not decreased, but a slight increase in COD removal was observed. These phenomena indicated that both methanogenic bacteria and sulfate reducing bacteria (SRB) could exist in the system as synthrophism. Maximum COD and sulfate removal were 86... 

Bacillus sp. As-101 which produces flocculating substances was isolated from activated sludge, using a proteolytic enzyme. Bioflocculant As-101 was partially purified by cold ethanol and cetylpyridinium chloride. The partially purified flocculating substance was an acidic polysaccharide including uronic, pyruvic and acetic acids, respectively, in an approximate ratio of 11.4%, 6.1%, 0.4%. The biopolymer is also a sugar-protein derivative consisting of glucose, mannose and galactose. The protein, the sugar contents ratio is about 83-17%. Bioflocculant As-101 acted under acidic condition and the maximum activity was observed at optimum pH ˜ 3.7 and optimum concentration of 30 ppm in kaolin... 

In order to produce bioethanol from agricultural residues such as wheat straw, the decomposition lignocellulosic materials into soluble sugars is necessary. This work focused on the influence of dilute sulphuric acid pretreatment conditions on sugar removal and the enzymatic saccharification of wheat straw. Response surface methodology (RSM) based on rotatable central composite design (RCCD) was used to optimise H 2SO 4-catalysed hydrothermal pretreatment of wheat straw, in respect to acid concentration (0.75-2.25%), treatment time (10-30min) and temperature (120-160°C). The pretreated wheat straw was hydrolysed by a standard blend of Cellusoft CR ®. Enzymatic hydrolysis was also measured to... 

Phosphatidylcholine (PC) possesses amphiphilic characteristics to form vesicles or liposome nanoparticles and can be utilized to deliver essential nutrients such as proteins, peptide antigens, and essential fatty acids. In this study, an attempt has been made to obtain purified PC and evaluate its potential in nanoliposome synthesis and its corresponding drug release profile. In this regard, four physical separation techniques comprising extraction, precipitation, static, and dynamic adsorption were assessed and applied to purify PC from soybean lecithin. Different solvents and the ratio of lecithin to solvent were used to achieve the highest PC percentage. The results of an HPLC test showed... 

Phosphatidylcholine (PC) possesses amphiphilic characteristics to form vesicles or liposome nanoparticles and can be utilized to deliver essential nutrients such as proteins, peptide antigens, and essential fatty acids. In this study, an attempt has been made to obtain purified PC and evaluate its potential in nanoliposome synthesis and its corresponding drug release profile. In this regard, four physical separation techniques comprising extraction, precipitation, static, and dynamic adsorption were assessed and applied to purify PC from soybean lecithin. Different solvents and the ratio of lecithin to solvent were used to achieve the highest PC percentage. The results of an HPLC test showed... 

This paper intends to introduce a simple fast space-efficient linear method for a general pattern recognition problem. The presented algorithm can find the closest match for a given sample within a number of samples which has already been introduced to the system. The fact of using averaging and fuzzy numbers in this method encourages that it may be a noise resistant recognition process. As a test bed, a problem of recognition of spoken words has been set forth to this algorithm. Test data contain clean and noisy samples and results have been compared to that of a widely used speech recognition method, HMM