Urea-assisted water electrolysis in an alkaline environment effectively treats urine-rich wastewater and prevents the release of ammonia gas and nitrate pollution into groundwater and drinking water; these contaminants typically result from the discharge of untreated urea into rivers and lakes. On the other hand, Urea-assisted water electrolysis is an efficient method for electrochemically producing hydrogen from water, while simultaneously cleans urea-polluted water. During this process, urea is oxidized at the anode to produce N? and CO?, while pure hydrogen is produced at the cathode and can be easily collected as a valuable green fuel. Compared to conventional water splitting, this method requires 70% less thermodynamic energy to produce H?. Expanding this technology to industrial applications, such as treatment of wastewater plants and farms, could prevent health problems and costs associated with toxic gas emissions, and contribute to the emerging hydrogen economy. In this thesis, two nickel-based bifunctional catalysts were synthesized, and their feasibility for use in the urea oxidation reaction (UOR) and hydrogen evolution reaction (HER) was investigated due to their superior electrocatalytic performance. In Chapter 1, an introduction to Urea-assisted water electrolysis and its importance is provided. In Chapter 2, a cerium-nickel bimetallic metal-organic framework (NiCe-MOF) was synthesized on nickel foam (NF) via a solvothermal method to enhance its conductivity and electrochemical properties. The prepared nanocomposite was characterized using various techniques, including X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and Field emission scanning electron microscope (FESEM). The structure of NiCe-MOF/NF was thereby determined. The electrocatalytic performance of the modified electrode toward UOR in an alkaline solution containing 0.5 M urea was evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and other electrochemical methods. Compared to stepwise-modified electrodes, the urea oxidation current on NiCe-MOF/NF was substantially increased and exhibited high stability after 200 potential cycles between 0.0 and +0.8 V. Furthermore, chronopotentiometry (CP) performed at a constant current density of 20 mA cm?² showed a very small potential drop for NiCe-MOF/NF over 20 h, confirming its excellent stability. On the other hand, linear sweep voltammetry (LSV) studies showed excellent electrocatalytic performance towards HER (in KOH, 1 M), with an overpotential of 145 mV at a current density of 10 mA cm?². Furthermore, CP stability tests demonstrated good stability of the proposed catalyst during 20 h of HER operation. The fabricated two-electrode cell, consisting of (-)NiCe-MOF/NF?NiCe-MOF/NF(+), required only 2.22 V to reach a current density of 100 mA cm?² and exhibited excellent stability, with just a slight voltage drop after 20 h of Urea-assisted water electrolysis. The superior electrochemical performance toward urea oxidation and hydrogen evolution was attributed to the effective synergy between nickel and cerium within the MOF structure. In Chapter 3, a chalcogenide was employed in the preparation of an efficient bifunctional electrocatalyst for H2

   Abstract: In the present research work, to begin with, a green preparation method was used for the synthesis of silver nanoparticles by hydrothermal method using natural materials of fresh and green skins of walnuts, onions and berries. The average diameter of silver nanoparticles was estimated to be 16 to 22 nm through transmission electron microscopy. In the first work, silver nanoparticles were used to identify types of water with different origins. Based on this, using the image processing method based on the color change of the silver nanoparticles solution after adding different waters to it, it was suggested. To perform the experiments, a plate with a plate was used, and finally, a photo of the plate was taken by a mobile phone camera, and RGB was taken from the photo by image analyzer software, then the RGB data was used to analyze the samples. Based on this method, the accuracy of the data obtained for water samples was 71.7%. In the second work, using chemometry and designing a colorimetric sensor based on silver nanoparticles, a method for detecting the percentage of ethanol in water-ethanol mixture was presented. In this work, by using the plates and taking pictures from them and analyzing the RGB data, the percentage composition of the unknown samples from the water-ethanol mixture was identified.   

  Abstract  Breast cancer is one of the most serious threats to women's health. Currently, conventional treatment methods for cancer, such as chemotherapy and radiotherapy, often prove to be less suitable due to the side effects they induce in tissues and other organs, making them less effective. In recent years, the utilization of nanotechnology has paved the way for the design and synthesis of various nanocarriers that can specifically deliver therapeutic agents to tumor cells. Biopolymer-based nanocarriers, including protein-based nanocarriers, have gained significant attention in research due to their low toxicity, biocompatibility, biodegradability, and ability to modify their structures. Sericin, one of the major proteins in silk, consisting of 18 amino acids, possesses high biodegradability, non-toxicity to normal cells, and also exhibits a pH-charge reversal characteristic, resulting in the increased release of the therapeutic agent in the tumor microenvironment. The anti-solvent precipitation (Asp) method will be employed to prepare the sericin-based protein nanocarrier. In this method, sericin protein is initially dissolved in an organic solvent, and by slowly adding it to a non-solvent, sericin molecules undergo self-assembly to form nanocarriers. This study aims to utilize sericin silk protein-based nanocarriers for encapsulating the anticancer drug cisplatin. It is well-established that cisplatin exerts its cytotoxic properties by binding to nuclear DNA and interfering with DNA replication and transcription mechanisms. In a slightly acidic tumor condition, the surface charge of sericin undergoes a pH-driven conversion from negative to positive, demonstrating that pH can regulate surface charge. The positively charged nanocarriers in the acidic tumor environment, facilitate enhanced interaction with tumor cells due to the charge attraction between the positively charged nanocarrier and the negatively charged surface of the cancer cells.

AbstractOil effluentsand oil-water emulsions are two examples of the main environmental pollutants.Although their amount is small in volume, but they have a high level ofpollution. In this study, the results of experimental studies of wastewatertreatment Oil and oil refinery of Kermanshah refinery has been presented byultrafiltration method using metal-organic frameworks (MOF) of TMU-5 type. TheDAF system and after the aeration system, Kermanshah refinery has been used asfeed. Has been reviewed. The results show that the flux and FRR increase withincreasing cross-sectional pressure and velocity. Analysis of treated effluentshows reduction of oil & grease, TSS, COD and turbidity by 100%. Comparisonof the obtained results shows the superiority of ultrafiltration method overbiological. The results indicate that treatment of effluent from refinery withultrafiltration process is possible. Is acceptable and the treated effluent isin accordance with environmental discharge standards.  AbstractOil effluentsand oil-water emulsions are two examples of the main environmental pollutants.Although their amount is small in volume, but they have a high level ofpollution. In this study, the results of experimental studies of wastewatertreatment Oil and oil refinery of Kermanshah refinery has been presented byultrafiltration method using metal-organic frameworks (MOF) of TMU-5 type. TheDAF system and after the aeration system, Kermanshah refinery has been used asfeed. Has been reviewed. The results show that the flux and FRR increase withincreasing cross-sectional pressure and velocity. Analysis of treated effluentshows reduction of oil & grease, TSS, COD and turbidity by 100%. Comparisonof the obtained results shows the superiority of ultrafiltration method overbiological. The results indicate that treatment of effluent from refinery withultrafiltration process is possible. Is acceptable and the treated effluent isin accordance with environmental discharge standards.    AbstractOil effluentsand oil-water emulsions are two examples of the main environmental pollutants.Although their amount is small in volume, but they have a high level ofpollution. In this study, the results of experimental studies of wastewatertreatment Oil and oil refinery of Kermanshah refinery has been presented byultrafiltration method using metal-organic frameworks (MOF) of TMU-5 type. TheDAF system and after the aeration system, Kermanshah refinery has been used asfeed. Has been reviewed. The results show that the flux and FRR increase withincreasing cross-sectional pressure and velocity. Analysis of treated effluentshows reduction of oil & grease, TSS, COD and turbidity by 100%. Comparisonof the obtained results shows the superiority of ultrafiltration method overbiological. The results indicate that treatment of effluent from refinery withultrafiltration process is possible. Is acceptable and the treated effluent isin accordance with environmental discharge standards.

Thelack of energy resources and pollution caused by the consumption of fossilfuels have led scientists to look for cleaner alternatives.Microbial fuel cell (MFC), as one of thebiochemical systems, has attracted theresearcher's attention due to the simultaneous energy production and wastewater treatment. The proton exchange membranes play avital role in MFC performance; their modification can lead to improvement inMFC performance and electricity generation. In the present study, sulfonated polyether sulfone (SPES) was used asthe polymer matrix, and nanoparticles were added in three weight percentages(0.1, 0.5, 1) and the results were compared. In the first work, ?-cyclodextrin (CD) and sulfonated ?-cyclodextrin (SCD) were used as nanoparticles.In the second work, Ni-Cr layered double hydroxide (LDH) was used, which was alsofunctionalized by sulfanilamide and (FLDH) was obtained. Finally, in the thirdwork, a combination of SCD and LDH was used as SCDFLDH nanoparticles.Nanoparticles and membranes were examined by various analyzes such as FTIR,SEM, EDX, WU, WCA, etc. The performance of the system was also checked byvariables such as columbic efficiency and power production. It was observedthat the modification of SPES membranes by these nanoparticles led to theimprovement of membrane properties including hydrophilicity and protonconductivity, due to their structure and many functional groups. Finally, bycomparing the results in each of the works, the membrane that showed betterperformance was introduced, which were SPES/S?CD 0.5% in the first work andSPES/FLDH 0.5% and SCDFLDH 0.5% in the second and third work respectively.Overall, the 0.5% SCDFLDH membrane had the best performance. This result wasconfirmed by the long-term performance of the mentioned membrane in MFC, andthe production power was 7.122 W/m2. As a result, the abovemembranes couldbe efficiently applied in MFCs for electricity generation and wastewatertreatment.Thelack of energy resources and pollution caused by the consumption of fossilfuels have led scientists to look for cleaner alternatives. MFC, as one of thebiochemical systems, has attracted the attention of researchers due to thesimultaneous energy production and wastewater treatment. The present study wascarried out with the aim of modifying the proton exchange membrane bynanoparticles and investigating their performance in microbial fuel cells. Inall works, sulfonated polyether sulfone (SPES) was used as the polymer matrix,and nanoparticles were added in three weight percentages (0.1, 0.5, 1) and theresults were compared. In the first work, ?-cyclodextrin (CD) and sulfonated ?-cyclodextrin (SCD) were used as nanoparticles.In the second work, Ni-Cr layered double hydroxide (LDH) was used, which was alsofunctionalized by sulfanilamide and (FLDH) was obtained. Finally, in the thirdwork, a combination of SCD and LDH was used as SCDFLDH nanoparticles.Nanoparticles and membranes were examined by various analyzes such as FTIR,SEM, EDX, WU, WCA, etc. The performance of the system was also checked byvariables such as columbic efficiency and power production. It was observedthat the modification of SPES membranes by these nanoparticles led to theimprovement of membrane properties including hydrophilicity and protonconductivity, due to their structure and many functional groups. Finally, bycomparing the results in each of the works, the membrane that showed betterperformance was introduced, which were SPES/S?CD 0.5% in the first work andSPES/FLDH 0.5% and SCDFLDH 0.5% in the second and third work respectively.Overall, the 0.5% SCDFLDH membrane had the best performance. This result wasconfirmed by the long-term performance of the mentioned membrane in MFC, andthe production power was 7.122 W/m2. As a result, the abovemembranes can be a suitable option for application in microbial fuel cells.  

Design and preparation of a novel photocatalyst, based on polymethylhydrosiloxane (PMHS) was reported. To investigate the straightforward preparation of PMHS-PEG-xT-PW, different characterization methods including FTIR, XRD, FESEM, UV-Vis DRS, EDX, PL, and EIS were utilized. The prepared photocatalyst was used for the photocatalytic degradation of Rhodamin B (RhB) under incident visible light irradiation and also efficiency of the catalyst was examined under sun light irradiation. To study the efficiency of this research for the photodegradation of RhB, the effect of different crucial parameters such as time of illumination, catalyst loading, RhB concentration, pH of the solution, reusability function of the catalyst and scavenger experiments were checked. Trapping tests showed that the photogenerated O2•- and 1O2 are the main active species involved in the photocatalytic process. Photoactivity of glass coated PMHS-PEG-xT-PW were also investigated in photodegradation of the RhB which showed about 90% dye removal after 4 h. Thus introduced photocatalyst showed excellent activity in suspension and fix bed reactor. This inorganic based polymer can not only extend the absorption wavelength range of TiO2 but also consequently increase life-time of excited electron and hole with an appropriate viscosity for casting, which improve the photocatalytic efficiency of the photocatalyst in fix bed reactor too. Stability and reproducibility of coated film were also evaluated. The charge transfer resistance was also decreased compare with bare TiO2 which was proved by Nyquist and Bode plots.

   Quantum dots are semiconductor nanocrystals that have tunable emission through changes in their size. Producing bright, efficient quantum dots with stable fluorescence is important for using them in applications in lighting, photovoltaics, detection, and biological imaging. This study designed to optimize the process for coating CdTe quantum dots with a ZnS to increase their fluorescence and stability and using of CdTe/ZnS for analytical application. Core-shell CdTe/ZnS quantum dots with 3-mercaptopropionic acid (MPA) as stabilizer were successfully synthesized by hydrothermal method in aqueous solution. These quantum dots have advantages compared to usual quantum dots with limited biological applications and high toxicity. Corresponding experimental results revealed that the fluorescence of MPA-TGA-CdTe/ZnS QDs could be effectively quenched by increasing NR and the photo luminescence (PL) of QDs was into turn –off, the static quenching was quenching mechanism that occurred between NR and QDs. After the addition of Naproxen, the strong covalent conjugation between NR and Naproxen allowed NR to form more stable complex with Naproxen, and separated from the surface of MPA-TGA-CdTe/ZnS QDs, thus, the QDs turned-on and the fluorescence intensity of QDs recovered .The detection limits of naproxen was 5.12×10-6mol.l-1 .The interactions of Naproxen , neutral red (NR) and 3-mercaptopropionic acid (MPA) capped MPA-TGA-CdTe/ZnS quantum dots (QDs) made a solid base for the controlling of the fluorescent reversible of QDs. This research characterized by means of Powder X-ray diffraction, Fourier transform infrared, ultraviolet–visible absorption, fluorescence (FL), spectroscopy and High Resolution transmission electron microscopy.

Synthesis, Characterization and Application of Magnetic Boehmite Nanoparticles

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