http://dspace.aiub.edu:8080/jspui/handle/123456789/9 Thu, 02 Apr 2026 02:30:19 GMT 2026-04-02T02:30:19Z http://dspace.aiub.edu:8080/jspui/handle/123456789/2604 Title: Spectral correlation of synthesized ethyl-4-(subs. phenyl)-6-methyl-2-oxo (or thio)-1, 2, 3, 4-tetrahydropyrimidine-5-carboxylate Authors: Halim, Md. E.; Khan, M. N.; Shaha, U.; Rahman, M. H.; Akhter, K.; Ahmed, S. M. Abstract: Urea or thiourea, ethyl acetoacetate, and substituted aromatic aldehydes were combined in a one-pot Biginelli coupling reaction to create a few 1, 2, 3, 4-tetrahydro pyrimidine-5-carboxylate derivatives without any unsafe organic solvent. The catalyst used for this reaction was nickel nitrate hexahydrate [Ni(NO3)2.6(H2O)]. The elemental analyses, mass spectral data, 1H-NMR, 13C-NMR, UV, and IR were used to characterize the separated pure products. Description: Ok Mon, 30 Dec 2024 00:00:00 GMT http://dspace.aiub.edu:8080/jspui/handle/123456789/2604 2024-12-30T00:00:00Z http://dspace.aiub.edu:8080/jspui/handle/123456789/1883 Title: Dye-sensitized solar cell with plasmonic gold nanoparticles modified photoanode Authors: Kabir, Daiyaan; Forhad, Taseen; Ghann, William; Richards, Balvin; Rahman, Mohammed M.; Uddin, Md. Nizam; Rakib, Md. Refat J.; Shariare, Mohammad Hossain; Chowdhury, Faisal I.; Rabbani, Mohammad Mahbub; Bahadur, Newaz M.; Uddin, Jamal Abstract: The depletion of fossil fuel and environmental anxieties has led to a greater interest in renewable forms of energy. To a large extent, the most prevalent form of renewable energy presently is solar energy. The Dye-sensitized solar cell (DSSC) is a promising substitute for all too familiar silicon solar cells. DSSC uses dyes as light-harvesting pigments in the conversion of solar energy to electric energy. This study is about the fabrication of DSSC using a photoanode made up of TiO 2 fused with gold nanoparticles. Gold nanoparticles enhance the performance of DSSC due to the plasmonic effect. The gold nanoparticles were made by the citrate method and characterized using UV–visible spectroscopy and dynamic light scattering. The performance of the solar cells was accessed via photocurrent and photovoltage measurements. The solar-to-electric power efficiency of the solar cells with gold nanoparticles was found to be about 50% higher than those without gold nanoparticles. Description: N/A Thu, 25 Feb 2021 00:00:00 GMT http://dspace.aiub.edu:8080/jspui/handle/123456789/1883 2021-02-25T00:00:00Z http://dspace.aiub.edu:8080/jspui/handle/123456789/1880 Title: Cobalt Oxide Nanorod-Modified GCE as Sensitive Electrodes for Simultaneous Detection of Hydroquinone and Catechol Authors: Sultana, Nasrin; Shawon, Sanjay Datta; Nayem, S. M. Abu; Hasan, Md. Mahedi; Islam, Tamanna; Shah, Syed Shaheen; Rabbani, Mohammad Mahbub; Aziz, Md. Abdul; Ahammad, A. J. Saleh Abstract: An electrochemical sensor based on a cobalt oxide nanorod (Co3O4NR) modified glassy carbon electrode (GCE) (Co3O4NR-GCE) was prepared for simultaneous and selective determination of hydroquinone (HQ) and catechol (CT). Surface morphology and crystallinity of Co3O4NR were investigated employing field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analysis. The structure (16 nm) of the Co3O4 nanorod was observed in the FESEM image. A sharp peak pattern in the XRD survey revealed the following crystal planes in Co3O4NR material: (111), (220), (311), (222), (400), (422), (511), and (440). Electrochemical characterization of modified Co3O4NR-GCE was carried out performing cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Selective and simultaneous detection of HQ and CT was carried out by performing CV and differential pulse voltammetry (DPV) analysis. In both studies, modified Co3O4NR-GCE showed well defined oxidation and reduction peaks for HQ and CT with enhanced peak current, and the oxidation peaks for HQ and CT were observed at 0.152 V and 0.254 V, respectively, in the CV analysis. Scan rate and pH variation analysis were performed to evaluate different kinetic parameters, including charge transfer coefficient (α = 0.56 for HQ and 0.66 for CT), heterogeneous charge transfer rate constant (ks = 56 for HQ and 72 for CT), and the number of electrons involved in HQ and CT oxidation. Quantitative analysis of HQ and CT was studied by observing the current response of DPV analysis with respect to concentration variation. Here, the detection limit was calculated as 0.2 µM for HQ with a linear concentration range of 5–200 µM, and 0.4 µM for CT with a linear concentration range of 5–150 µM. The practical applicability of the proposed sensor was investigated using sample solutions prepared in tap water. The reported sensor showed impressive selectivity towards HQ and CT in the presence of common interferents. Description: N/A Thu, 17 Feb 2022 00:00:00 GMT http://dspace.aiub.edu:8080/jspui/handle/123456789/1880 2022-02-17T00:00:00Z http://dspace.aiub.edu:8080/jspui/handle/123456789/1816 Title: A Review on Potential Electrochemical Point-of-Care Tests Targeting Pandemic Infectious Disease Detection: Covid-19 as a Reference Authors: Biswas, Gokul Chandra; Choudhury, Swapnila; Rabbani, Mohammad Mahbub; Das, Jagotamoy Abstract: Fast and accurate point-of-care testing (POCT) of infectious diseases is crucial for diminishing the pandemic miseries. To fight the pandemic coronavirus disease 2019 (COVID-19), numerous interesting electrochemical point-of-care (POC) tests have been evolved to rapidly identify the causal organism SARS-CoV-2 virus, its nucleic acid and antigens, and antibodies of the patients. Many of those electrochemical biosensors are impressive in terms of miniaturization, mass production, ease of use, and speed of test, and they could be recommended for future applications in pandemic-like circumstances. On the other hand, self-diagnosis, sensitivity, specificity, surface chemistry, electrochemical components, device configuration, portability, small analyzers, and other features of the tests can yet be improved. Therefore, this report reviews the developmental trend of electrochemical POC tests (i.e., test platforms and features) reported for the rapid diagnosis of COVID-19 and correlates any significant advancements with relevant references. POCTs incorporating microfluidic/plastic chips, paper devices, nanomaterial-aided platforms, smartphone integration, self-diagnosis, and epidemiological reporting attributes are also surfed to help with future pandemic preparedness. This review especially screens the low-cost and easily affordable setups so that management of pandemic disease becomes faster and easier. Overall, the review is a wide-ranging package for finding appropriate strategies of electrochemical POCT targeting pandemic infectious disease detection. Description: N/A Mon, 11 Jul 2022 00:00:00 GMT http://dspace.aiub.edu:8080/jspui/handle/123456789/1816 2022-07-11T00:00:00Z