http://103.99.128.19:8080/xmlui/handle/123456789/110 Chemistry Mon, 05 Oct 2026 13:34:00 GMT 2026-10-05T13:34:00Z http://103.99.128.19:8080/xmlui/handle/123456789/600 Title: ISOLATION OF MUCILAGE FROM THE FRUITS OF Momordica charantia AND INVESTIGATION OF ITS PHARMACOLOGICAL PROPERTIES Authors: Chowdhury, Tahamina Momtaz; ID:, 19MSCHEM005F Abstract: Momordica charantia is a plant belonging to the Cucurbitaceae family, also known as ‘Bitter gourd’, and ‘Usta’ in bangle. It contains alkaloids, insulin-like polypeptides, and charantin, a combination of steroidal sapogenins. It is an effective hypoglycemic agent. Momordica charantia is the most common plant used in alternate medicines as an anti-diabetic agent. Metformin hydrochloride is derived from the class of compounds from biguanide family, is an oral anti-hyperglycemic agent and is widely used as an anti-diabetic drug in the treatment of non-insulin-dependent diabetes mellitus (NIDDM). The action of Metformin is the alteration of the energy metabolism of the cell. By blocking hepatic gluconeogenesis and glucagon's action, metformin has its predominant effect of lowering blood glucose levels. Metformin has 50-60% bioavailability and 1.5–4.5 hours for plasma half-life. Initial dose (800 mg) required in orally once a day .Therefore, in the case of higher diabetes, higher doses are required, there is a need to take this medicine 2–3 times in a day. In the current study, the mucilage isolated from Momordica charantia fruits and used in the tablets formulations as a binding agent. Different phytochemical test of isolated mucilage showed that only carbohydrates is present in it. We have designed nine batch tablets containing 500 mg of Metformin HCl with different compositions of mucilage (1%, 2.5%, 5%, and 10%) for 800 mg of each tablet. The pre-compressional and post-compressional pharmacological properties of different formulated granules and tablets are evaluated. The granules showed good to excellent flow properties based on the values of bulk density, tap density, carr’s index, hausner's ratio and angle of repose. The weight of the tablets is close to the standard and shown good hardness properties. Among all the formulations, the tablets batches of formulation 4 (F4) and formulation 8 (F8) have good disintegration properties. From in vitro dissolution profile analysis, formulation batch F 4 composed of 10% mucilage and F-8 composed of 10% mucilage along with 10 % starch, released 40.8% and 31.63% of the drug, respectively in 60 minutes. Drug Release Kinetics Study showed that F4 showed the first-order release kinetics and F-8 showed the zero order and the Higuchi-s release kinetics. Hence, mucilage from Momordica charantia can be used as excipients or tablet binders for low cost, available, nontoxic in pharmaceutical tablet formulations. Description: A Master of Science (M.Sc) Thesis in Chemistry Department at Chittagong University of Engineering and Technology (CUET). Thu, 29 May 2025 00:00:00 GMT http://103.99.128.19:8080/xmlui/handle/123456789/600 2025-05-29T00:00:00Z http://103.99.128.19:8080/xmlui/handle/123456789/584 Title: VISIBLE- LIGHT DRIVEN PHOTOCATALYTIC DEGRADATION OF ORGANIC POLLUTANTS OVER CuWO4@TiO2 NANOCOMPOSITE: A COMBINED EXPERIMENTAL AND THEORITICAL STUDIES Authors: Dutta, Keya Rani; ID:, MSCHEM014F Abstract: With the growing presence of organic pollutants like methylene blue (MB) in wastewater, there are significant concerns for both the environment and public health, highlighting the urgent need for the development of effective remediation strategies. This study addressed the urgent need for effective remediation strategies for organic pollutants, specifically methylene blue (MB), in wastewater by synthesizing and evaluating a CuWO₄@TiO₂ nanocomposite photocatalyst. A comprehensive characterization using UV-Vis diffuse reflectance spectroscopy (DRS), field emission scanning electron microscopy (FESEM), X ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface area analysis, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) was conducted to assess the nanocomposite's structural, morphological, and electrochemical properties. Density functional theory (DFT) calculations provided insights into the photocatalytic mechanism, particularly the most stable Ti/Cu@CuWO₄ interface configuration. To enhance predictive modeling for MB degradation, ten machine learning (ML) algorithms, including AdaBoost, Bagging, CatBoost, Decision Tree, Extra Trees, Gradient Boosting, HistGradientBoosting, LightGBM, Random Forest, and XGBoost, were evaluated based on coefficient of determination (R²), mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), and median absolute error (MedAE). Among this HistGradientBoosting model demonstrating exceptional performance, achieving an R² of 0.9998 in training and 0.9915 in testing, along with low error metrics. Experimental validation under optimal conditions (200 mg/L catalyst, 150 mW/cm² light intensity, 88.6 min reaction time) confirmed a 98.5% MB degradation efficiency, closely aligning with the ML-predicted 98.99%. The nanocomposite exhibited significantly higher catalytic activity as compared to individual CuWO₄ and TiO₂, with rate constants of 0.0302 min⁻¹ for the nanocomposite, 0.0197 min⁻¹ for CuWO₄, and 0.0167 min⁻¹ for TiO₂. Scavenger experiments revealed the order of active species in the degradation process as O₂•⁻ > HO• > ¹O₂ > e⁻ > h⁺, this research emphasizing the combined effectiveness of experimental, computational, and machine learning methods in optimizing photocatalytic water treatment processes. Description: A Master of Science (M.Sc) Thesis in Chemistry Department at Chittagong University of Engineering and Technology (CUET). Wed, 30 Apr 2025 00:00:00 GMT http://103.99.128.19:8080/xmlui/handle/123456789/584 2025-04-30T00:00:00Z http://103.99.128.19:8080/xmlui/handle/123456789/582 Title: STUDY ON WASTE WATER TREATMENT PROCESS AND ASSESSMENT OF HEAVY METAL CONCENTRATION IN DIFFERENT TYPES OF ETP AND STP IN SOME INDUSTRIES AT CHATTOGRAM REGION Authors: Hassan, Md. Kamrul; ID:, 18MCHEM012P Abstract: This study delves into a comprehensive assessment of Wastewater Treatment Plants including Effluent Treatment Plants (ETPs) and Sewerage Treatment Plants (STPs) within diverse industries in Chattogram Division, Bangladesh. The investigation was mainly focused on the analysis of ETP samples obtained from the steel and paint industries located in Mirsharai, Sitakunda, Karnaphuli, and Kalurghat industrial areas of Chattogram, as well as STP samples collected from hotels in Cox's Bazar of Chattogram Division. These industries release complex liquid waste rich in dissolved solids, suspended particles, and heavy metal ions. Considering the economic and environmental significance of Chattogram and the detrimental effects of water pollution on ecosystems, the assessment of the discharge of effluents from those industries into water bodies becomes imperative. Thus, this study aims to find out the operational maintenance practices in wastewater treatment plants and to analyze the water quality in ETP samples and STP samples from the industries mentioned above in terms of studying various physio-chemical parameters before and after discharge from the treatment plants. Effluent samples were collected from the ETPs and STPs bi-annually during the dry season (D.S., January- February) and monsoon season (M.S., July- August) using systematic and standardized analytical methods. Sampling procedures involved collecting effluent samples from both the inlet and outlet points of the industrial ETPs and STPs. The water quality was evaluated based on five physio-chemical parameters, namely pH, dissolved oxygen (DO), biological oxygen demand (BOD5), chemical oxygen demand (COD), total dissolved solids (TDS), as well as the concentration of heavy metals including Fe, Cu, Cr, Ni, and Cd. The results were compared to national and international regulations, such as the Bangladesh Standard for Industrial Effluent (BSIE) of Department of Environment (DoE), World Health Organization (WHO) guidelines, European Union Directives (EU-DIR), and US Environmental Protection Agency (US EPA). It was observed that steel-galvanizing industries generate complex wastewater rich in highly dissolved solids and heavy metal ions. Although pH, BOD5, and COD values were within acceptable ranges in these industries, high TDS values were observed. The Fe concentration of discharged stream areas ranged from 0.992 mg/L to 16.89 mg/L, exceeding the guideline limits. Additionally, the Cr concentration in both the inlet and outlet exhibited high concentrations, surpassing the standard limits, particularly those set by the US EPA. Thus, steel-galvanizing industries are likely contributing to water pollution through the discharge of wastewater, particularly in terms of Fe and Cr. In the case of the Paint Industries, after treatment, Fe concentration of discharged stream areas ranged from 2.333 mg/L to 5.117 mg/L exceeded the guideline limits of WHO and BSIE standards and indicated probable water pollution by Fe. Ni in those samples was under the safe limit, and Cd was found under the detectable limit. This study examined the operation of STPs in three Hotel Industries and assessed their impact on water quality in Cox's Bazar, Chattogram Division. Notably, pH levels remained relatively stable, while DO levels fluctuated. The fluctuations of COD levels reflect the presence of various pollutants and similar trends were observed for BOD5. Additionally, TDS indicated the presence of dissolved substances and solid particles. Furthermore, elevated nitrate and phosphate levels raised concerns about nutrient pollution and eutrophication. Fe concentrations remained within regulatory limits, but Cu exceeded limits in specific areas, requiring further investigation. Cr concentrations were within acceptable ranges, while Mn levels significantly exceeded defined limits. Finally, the findings of this study underscore the importance of adopting comprehensive measures and optimizing wastewater treatment processes to address pollution in different industries. Description: A Master of Philosophy (M.Phil.) Thesis in Chemistry Department at Chittagong University of Engineering and Technology (CUET). Wed, 26 Feb 2025 00:00:00 GMT http://103.99.128.19:8080/xmlui/handle/123456789/582 2025-02-26T00:00:00Z http://103.99.128.19:8080/xmlui/handle/123456789/546 Title: SIMULTANEOUS REMOVAL OF ANTIBIOTIC AND ANTIBIOTIC RESISTANT BACTERIA BY NANOMATERIAL Authors: Maya, Akser Alam Siddiqua Abstract: The increasing prevalence of antibiotics in water systems poses significant environmental and health concerns, including antibiotic resistance and genotoxicity. This research focuses on synthesizing FeWO4 nanomaterials in three distinct morphologies- nanoparticles, nanorods, and nanofibers via a sustainable hydrothermal process. These nanomaterials were evaluated as heterogeneous catalysts in four different Fenton-based processes: conventional Fenton (CF), photo-Fenton (PF), sono-Fenton (SF), and sono-photo-Fenton (SPF). The performance of each morphology was systematically assessed for the degradation of ciprofloxacin (CIP), a common antibiotic pollutant found in water. The synthesized nanomaterials were characterized using UV-Vis, FESEM, XRD, XPS, EIS, and cyclic voltammetry (CV). The physicochemical analysis also confirmed differences in catalytic performance based on changes in their morphologies. The Response Surface Methodology (RSM) and Central Composite Design (CCD) were used to improve the degradation of CIP by altering three independent variables: solution pH, catalyst dose (mg/L), and reaction time (min). The quadratic model was found to be significant through analysis of variance (ANOVA). This mathematical model fits the experimental data satisfactorily, with R2 = 0.9953 and lack of fit = 0.2441 (P>0.05). Almost complete degradation was achieved at the optimum doses of 100 mg/L of FeWO4, pH = 7, and a 40-minute reaction time. Among the Fenton processes, PF and SPF demonstrated higher antibiotic degradation efficiency than CF and SF processes. Notably, FeWO4 nanoparticles exhibited the best performance, achieving complete degradation of CIP under optimized conditions of pH 7, FeWO4 dosage of 100 mg/L, and a reaction time of 40 minutes, with initial concentrations of 10 mg/L for CIP and 2 mM for hydrogen peroxide (H2O2). FeWO4 nanoparticles were found to be effective for inactivation of ARB E. Coli RP4 by 6.45 log within 20 min. No ARB regrowth occurred after 72 h, which demonstrates the efficacy of this approach in achieving permanent removal of ARB. The synthesized FeWO4 nanoparticles have the potential to degrade demonstrated stability and recyclability, generating potent reactive species such as hydroxyl radicals (HO•), superoxide radicals (O2 •-), and singlet oxygen (1O2). These findings underscore the potential of FeWO4 nanoparticles as effective heterogeneous catalysts in advanced oxidation processes for mitigating antibiotics and antibiotic-resistant bacteria in aquatic environments. Description: A Master of Science (M.Sc) Thesis in Chemistry Department at Chittagong University of Engineering and Technology (CUET). Sun, 08 Dec 2024 00:00:00 GMT http://103.99.128.19:8080/xmlui/handle/123456789/546 2024-12-08T00:00:00Z