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... 

Micropollutants are a wide group of organic compounds that are detected in most compartments of the environment. Their environmental concentration is usually in the range of few ng/l to mg/l, but they remain biologically active even at such low concentrations; may be accumulated through the food chain, and pose a serious threat to the environment, fauna, and human health. Among micropollutants, pharmaceutical active compounds (PhACs) are of special concern. It is accepted that the main sources of PhACs in the environment are effluents from wastewater treatment plants (WWTPs), where conventional activated sludge processes are not able to degrade most of them. To address these concerns, the... 

Polychlorobiphenyl compounds are a class of persistent organic pollutants consisting of two biphenyl rings and chlorine substations. Polychlorobiphenyls do not dissolve in water, are very stable at high temperatures, and are considered a good conductor. Due to the mentioned properties in the 1930s and 1940s, these compounds were widely used in various industries such as power plants, Painting industry, Plastics industry, etc. After years of use, these substances have been found to be very dangerous to the health of living organisms and the environment due to their high resistance to decomposition and the ability to accumulate in adipose tissue. Today, although the production and use of these... 

Pharmaceutical active compounds existence in the water would cause serious ecological risks and human health-related adverse effects which turn to environmental concern, therefore several studies have done to remove pharmaceutical active compounds efficiently. Carbamazepine (CBZ), a widely used psychiatric drug, is one of the most frequently detected compounds in the surface water and groundwater which is studies in the current study. Recently, biocatalytic degradation using ligninolytic enzymes such as laccase provides a promising approach for their removal from water and wastewater. In this work, carbamazepine removal by immobilized laccase on modified membrane by multi wall carbon nanotube... 

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... 

This research addresses the fabrication and characterization of a multilayered nanocomposite scaffold with a dual purpose for post-surgical bone cancer treatment . Eliminating residual cancer cells and promoting bone tissue regeneration. The scaffold was prepared from a combination of hydroxyapatite and 58S bioactive glass bioceramics in an 8 to 2 ratio. This bioceramic powder was combined with polylactic acid polymer, and scaffolds with precise and controlled geometry were fabricated using an FDM 3D printer. The design of this geometry facilitates cell infiltration, nutrient and waste transport, and ultimately, bone matrix formation. For anticancer properties, graphene oxide nanomaterial... 

Bisphenol A is one of Endocrine Disturbing Chemicals. Enzymatic removal of bisphenol A is an interesting and green method. However, application of enzymes has been hampered due to lower operational stability and lots of difficulties in recovery and recycling. Enzyme immobilization can ba an innovative approach to circumvent these drawbacks. Laccase from Trametes hirsuta used for Bisphenol A removal. Firstly, magnetic nanoparticles were synthesized by coprecipitation method and aminofunctionalized by (3-aminopropyl)-mmethoxysilane. Subsequently, laccase was precipitated with i-propanol in the presence of aminofunctionalized nanoparticles and followed by addition of glutaraldehyde to the final... 

Polychlorinated biphenyls are a group of hydrocarbons that are composed of two benzene rings and chlorine admixture on it. Due to their special properties, these materials were added to oils for years to improve their properties. These compounds have many industrial applications in various industries, such as the production of fluorescent lamps, adhesives, dyes, and especially as a cooling and insulating liquid as the Askarel oil in power transformers. Due to the properties of these compounds, which include stability and bioaccumulation in fatty tissues, the wide use of these substances causes environmental contamination and leads to a variety of cancerous diseases. Among the cleaning... 

Carbon nanotubes were coated with boehmite nanoparticles by sol gel method. According to the TGA analysis, formation of gamma-alumina from boehmite was at 500 . SEM investigation revealed the uniform coverage of gamma-alumina nanoparticles on the surface of CNTs. Composite powders containing 1, 2 and 3vol% of coated CNTs were produced by mixing the coated CNTs with alumina suspension. Phase analysis of composite powder calcined at 500 showed the complete decomposition of boehmite and formation of gamma-alumina. Samples were shaped by cold isostatic pressing at the pressure of 180MPa and sintering was performed using two different methods of conventional and microwave. Existance of the CNTs... 

One of the major environmental challenges in recent decades has been the presence and accumulation of micropollutants in water resources and natural ecosystems, leading to numerous adverse consequences for the environment and the health of living organisms. Among these compounds, endocrine-disrupting pollutants are of particular importance due to the hormonal disturbances they cause. Bisphenol A (BPA) is one of the most well-known endocrine disruptors, raising significant concerns regarding its environmental and health risks. Traditional methods for removing these pollutants include biological and physicochemical processes, which often lack sufficient efficiency for complete BPA removal.... 

Polychlorinated Biphenyls are a class of organic compounds that are composed of two biphenyl rings attached by 1-10 chlorine atoms. Due to their specific properties, such as physical and chemical stability, flame resistance, and dielectric properties, these compounds are used as dielectric liquids, heat-exchange fluids, hydraulic liquids, plastifiers, and especially as Askarel oil in power plant transformer. Because of their high persistency in the environment, high toxicity, and bioaccumulation in the adipose tissue of humans and animals, their production is banned in most countries, and their use has been limited. There are different methods for detoxification of these compounds, and in... 

In this study, the co-pyrolysis process of textile waste based on cellulose and polyethylene terephthalate (PET) was investigated using thermogravimetric analysis (TGA/DTG). Additionally, the pyrolysis kinetics of the thermal degradation process for each material and their combinations were studied. Kinetic parameters, including activation energy (E) and pre-exponential factor (A), were calculated for the pyrolysis of the samples using iso-conversional kinetic models such as Friedman (FR), Kissinger-Akahira-Sunose (KAS), and Flynn-Wall-Ozawa (FWO) based on the TGA and DTG curve data and compared with the corresponding reported values. Furthermore, the pyrolysis kinetics were modeled using... 

Land subsidence is a gradual settling or sudden sinking of the land surface from changes that take place underground. There are different causes of land subsidence; most notably, groundwater overdraft and severe weather conditions. Subsidence of the land surface due to ground water overdraft is caused by an increase in the intergranular pressure in unconsolidated aquifers, which results in a loss of buoyancy of solid particles in the zone dewatered by the falling water table and accordingly compaction of the aquifer. In this study, an experimental approach was developed to examine applicability of Microbially induced carbonate precipitation (MICP) for land subsidence control under... 

Due to the environmental crisis caused by the accumulation of plastics and disposable containers in nature, along with the significant challenges associated with their waste management, finding effective solutions to reduce plastic-related pollution was considered essential. One potential approach to address this issue is the use of indigenous microorganisms capable of plastic biodegradation, as well as the replacement of conventional plastics with biodegradable bioplastics that, owing to their degradable structures, reduced the environmental pollution load. In this study, the biodegradability of bio-based disposable containers was investigated through the isolation and purification of... 

Contaminants in drinking water, including microbial contaminants, have a great impact on the health of people in the community and can seriously threaten public health. In recent years, diseases caused by pathogenic bacteria due to the consumption of contaminated water have led to many deaths. As a result, water treatment has been one of the most important human concerns. Among the new water treatment technologies, metal-organic(MOF) frameworks are a new generation of porous materials that have properties such as high surface area, water stability and functionality due to their dual structure. As a result, they are widely used today in various scientific fields, including water purification.... 

Treatment of Wastewater of textile industries has been always challenging due to the high organic matter which is a suitable substrate for the growth of microorganisms. Also, discharge of wastewater into the open water causes water adsorbing more sunlight, raising water temperature and therefor decreasing dissolved oxygen. In addition, the acidity of wastewater decreases the quality of agricultural soil. Among wastewater treatment methods, biological methods are cheaper, environment friendly, and produce less by product. Among all the microorganism responsible for biological treatment, fungi and enzymes are more applicable. Especially white-rot fungi are the most effective microorganism to... 

Microbially-induced calcium carbonate precipitation is a low-cost, environmentally friendly, novel ground improvement technique that has received much attention in recent years. Most studies on biological soil stabilization have investigated the mechanical and hydraulic behavior of soils in dry and saturated conditions. However, the behavior of soils stabilized by this method in the unsaturated state should be of immense concern through the extent of unsaturated soils in nature. Therefore, this study aims to investigate the effects of microbially-induced calcium carbonate precipitation on the soil-water retention curve and changes of small strain shear modulus of unsaturated cemented and... 

In recent years, non-biodegradable microplastics (MPs), which cause a lot of pollution in the environment, have become a major concern worldwide. Due to their small size and large surface area, these plastic particles have a great ability to be absorbed into biological cells. Due to their hydrophobic surface, these particles have the ability to absorb pollutants such as heavy metals, toxic medicinal substances, softeners, etc. Microplastics are usually persistent in the environment, allowing them to be transported along the food chain. Research on the degradation of microplastics is focused on biological and non-biological approaches. To date, microorganisms such as algae, fungi, and... 

Acidizing is the most widely performed job to remove the formation damage, and enhance the oil recovery. Different models have been introduced to design the optimized condition for acidizing. However, none of them are able to predict the optimum injection flow rate in the actual application. As a result, Calcite cores are extracted from reservoirs for conducting experiments and modifying the present models. Nevertheless, acidizing is an intrusive technique destroying the costly extracted cores. Thus, there is a need to construct calcite cores of various porosities and permeabilities to take advantage of them in acidizing modelling.Microbially induced calcite precipitation is a well-known... 

Understanding biological systems requires extensive knowledge of individual parameters, and to study the processes of cell differentiation and cell behavior, a suitable environment must be created with the physiological conditions of the human body. For this purpose, with the knowledge of microfluidics, a microenvironment can be provided to study the behavior of cells on a small scale. The use of bone tissue model microfluidic chips is an alternative and new method in which it is possible to study the behavior of cells to differentiate into bone and to examine the toxicity of drugs, which in itself can help in the effective and successful treatment of these cases show. Therefore, in this...