https://repository.auw.edu.bd/handle/123456789/639 2026-05-09T11:41:59Z https://repository.auw.edu.bd/handle/123456789/693 Anthracene conjugated carboxylic acids for luminescent materials: Design, synthesis and photophysical studies Kabir, Ahmedul Two new carboxylic acids conjugated with anthracene (1 and 2) are synthesized with a target to explore their coordination chemistry with metal ions. Compounds 1 and 2 are completely characterized by var- ious analytical (NMR, Elemental analysis and ESI-Mass) methods. The backbone (biphenyl and phenyl) of compounds1 and 2 differs in such a way that the electronic communication between carboxylic acid and anthracene moieties can be easily modified. Compound 2 show anthracene centred emission while 1 exhibit combination of charge transfer transition and anthracene centred emissions. Preliminary fluores- cence studies reveal compound 1 and 2 show different fluorescence response for first row transition metal ions. 2020-01-01T00:00:00Z https://repository.auw.edu.bd/handle/123456789/692 Mass-Transfer Coefficient as an Indicator of Resin Performance: Impacts of Film-Forming Amines and Storage Time on Condensate Polishing Ion-Exchange Resins Kabir, Ahmedul Ion-exchange resins used in ultrapure water processing are known to lose effectiveness with fouling. Mass- transfer coefficient (MTC) is one property that defines acceptable resin performance. MTC is measured by a simple column test with known feed concentration of ions at sufficient flow to achieve kinetic leakage out of bed. MTC deviation due to exposure to film-forming amines (FFAs), as well as impacts of resin storage time, are investigated. A filming amine (FA), octadecylamine (ODA), was evaluated experimentally for potential impacts on condensate polisher ion-exchange bead resins (Dowex MS 650C (H) and Dowex MS 550A (OH)). Results indicate significant reductions in MTC on both cationic and anionic resin. In addition, unused resin stored for excessive times, up to 16 years, showed MTC reduction. 2018-01-01T00:00:00Z https://repository.auw.edu.bd/handle/123456789/690 Studies Of Dissipation Pattern Of Cypermethrin In Tomato Kabir, Ahmedul Dissipation pattern of cypermethrin (Ripcord 10EC) on tomato plants sprayed at recommended and double the recommended doses followed first order kinetics. In both the doses residues were found below the maximum residue level (0.5 ppm) after one day of application. Recoveries were found to be 80.88% &77.09% spiked at 0.2 & 0.5 ppm, respectively. LOD and LOQ were found to be 0.01 and 0.06 ppm, respectively. 2013-01-01T00:00:00Z