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Item Synthesis Of Modified Conducting Polymers And Study Of Their Water Purification Capability(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2008-06) Das, Chinmoy Kumar; Yousuf, Dr. Mohammad AbuPerpetration, characterization and water purification capability of modified conducting polymers have been described. Synthesis of polyaniline (PANI), polyaniline-silica (PANI-silica), polyani line-stearate (PANI-stearate), polyanil me-sodium dodecyl sulfate (PANI-SDS) and polyaniline-ethylene diamine tetra acetic acid (PAN!-EDTA) were carried out at pH 3.1 and at room temperature in aqueous medium by in situ oxidative chemical polymerization process. These composites have been characterized by a wide range of experimental techniques including density analysis, optical microscopy, infra-red spectroscopy, UV-visible spectroscopy and adsorption capability. Elemental analysis for silica content indicate that the chemically synthesized PANI-silica composite contain as high as about I I % silica in the matrix. At the same time it was seen that only 3.9 % EDTA were impregnated in to the polymer matrix and has been confirmed by the complex metric titration. It was seen that the density of PANI-silica composite is higher than that of the bulk polymer. On the other hand, the densities of PANI-stearate, PANI-SDS and PANI-EDTA are smaller than that of the PANI matrix. Optical microscopic view provided very important and visualized information about the bulk polymer and the synthesized composite materials. The presences of white spots into the composites clearly indicate the incorporation of foreign particles into the polymer matrix. Infra-red spectroscopic studies yield useful qualitative information on PANI, PANI-silica, PANI-stearate, PANI-SDS and PANI-EDTA composites. From the spectra, the band characteristics of PANI and other PANI based composite materials confirm the formation of the respective polymer and the composites. !R spectra observed for the studied sample exhibited the appropriate adsorption bands those are attributable to both polymer and the composite component. Typical DTA and TGA analysis for the bulk PANI, PANI-silica, PANI-stearate, PAN!- SDS and PANI-EDTA composite materials provide the useful information about the formation composites and the characteristic thermal properties. Both from the DTA and TGA analyses it was seen that bulk PAN! and composite materials have strong affinity to water molecules, i.e., moisture that was about 40% of the total mass. Distinguishable weight loss at different phases with temperature shown in TGA clearly ascribable to the formation of composite materials. DTA also give the comparable data in favour of formation of composites and also the probable reaction involve in the experiment. Surface area measurements show that the PANI-silica composite have much higher than that of the bulk polymer. The incorporation of fine silica particles into the polymer might lead to this increased surface area. Adsorption of Mn2 and As3+ons on the PANI-silica matrix has been found to occur. At the same time PANl-stearate and PANI-SDS composite materials could be used as the trap for the Mn2 and As3 ions present in the water sample. On the other hand PANI- EDTA composite could adsorb only Mn2 ion from aqueous mediumItem Physico-Chemical Studies Of Different Solutions Of Electrolytes NH4C1, FeC13 and NiC12) IN Mixed Solvents (Water-DMSO)(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2008-08) Reza, K. M. Salim; Prof. Dr. Md. Abdul AzizThe volumetric, viscometric and some other related properties of DMSO in aqueous solutions and some electrolytes such as NH4C1, NiC12 and FeCl3 in water, DMSO and mixed solvents have been measured. The apparent molal volumes, and viscosities, of NH4Cl,NiC12 and FeCl3 in water and water-DMSO solutions were studied as a function of concentration at a wide range of temperatures of 288, 293, 298, 303, 308 and 313 K. The apparent molal volumes at infinite dilutions (limiting apparent molal volume) of these values to the zero concentrations which is practically equal to the partial molal volume. Limiting apparent molal volume for all the three electrolytes were determined by extrapolating co electrolytes studied showed higher values in aqueous DMSO solution then those in aqueous solution in the temperature range of 288 K to 313 K. Apparent molal volumes, , is depended upon the electrolyte concentration as well as on the temperature. Apparent molal volumes showed the gradual decrease of volume with concentration except FeCl3 in water and in pure DMSO solution. The value of viscosities increase in molality of the electrolytes except NH4Cl. No significant change of viscosity observed for NH4Cl with increase in molality in aqueous and in 20% aqueous-DMSO solutions. The viscosities, il for all the studied electrolytes are greater in aqueous DMSO solvent system than those in water system alone indicating that electrolytes in aqueous DMSO systems are more structural than those in aqueous system.Viscosity coefficients (A and B) for the above systems were also determined for the Jones Dole equation. B values for NiC12 and FeCl3 were found to be positive that indicate these electrolytes exhibit structure making behavior in water and in water-DMSO solutions. The B value is negative in water and water-DMSO for NH4C1.This indicates that NH4Cl salt behaves as a water structure breaker in aqueous and aqueous DMSO system. The coefficient A represents the solute-solute interactions coupled with size and shape effect of the solute and to some extent solute-solvent interactions. A coefficient was obtained with an irregular variation. The behaviors of three solutes in binary and ternary systems were discussed in terms of the charge, size and hydrogen bonding effect.Item Study on the Microbiological Hazards Present in Shrimp and Shrimp Culture Water for the Improvement of Sea Food Quality of Khulna Region, Bangladesh(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2009-11) Ali, Md. Abbas; Aziz, Prof Dr. Md. AbdulSea food quality and salty is mostly dependent on the microbiological parameters present in the shrimps. Microorganisms can reduce the quality of foods in various ways. They can change the food organoleptic ally so as to defer the potential consumer or they can make it capable of causing disease. There is no doubt that food related disease is extremely important the people are much more aware about the food borne disease, such as in UK in one year as much as 10% of population will suffer from a food- related disease and some death will result, usually amongst the most valuable the young throughout the world. In developed countries and the infirm. However. it is known that throughout the world in one year millions of young children die as a result of diarrheas much of which has been caused by organisms contracted from water or food. Shrimps are used as one of the most important chose able and delicious food item in the global market. To improve the quality, to fulfill the requirements of the consumer. to earn more foreign currency and to develop our socio-economic condition. The study has been taken. Shrimps (Penancus Monodon) and shrimps culture water were collected from different locations of Bagerhat, Satkhira and Khulna to perform microbiological analysis. It has been shown from the investigation that Standard Plate Count (SPC) was found within standard limit at Koyra (pond nos.l,2) Dumuria (pond nos.4.6), Paikgacha (pond nos.7,9), Rampal (pond nos. 1.3), Mongla (pond nos.4,6), Bagerhat city area (pond nos.8,9), Shamnagor (pond nos.1.2.3), Ashasuni (pond no.5) and Satkhira city area (pond no.8) of Khulna region for shrimps. It has also been shown for shrimps that Total Coliform (T.Coli) was within standard value at Koyra (pond nos.1.3), Dumuria (pond nos.5,6), Paikgacha (pond nos.7,8), Mongla (pond nos.4.5.6). Bagerhat city area (pond nos.7,8,9), Shamnagor (pond nos.2,3), ) and Satkhira city area (pond nos.7,8,9). The Faccal Coliforni (F.Coli) was found within standard value at Koyra (pond no.1), Dumuria (pond nos.5,6), Mongla (pond Ashasuni (pond no os.4.6). Bagerhat city area (pond nos.7.9), Shamnagor (pond no.2), Ashasuni (pond no.5) and Satkhira city area (pond no.8). Salmonella were found at Dumuria (pond no.4), Paikgacha (pond no.7). Rampal (pond nos.l,2), Mongla (pond no.6), Bagerhat city area (pond no.9) and Ashasuili (pond no.4) but Vihrio Cholerac were not found anywhere. It was found that Standard Plate Count (Slk') and Faccal Colitbrm (F,Coli) for shrimp culture water were found above the standard value in all the area. The Total Coliform (T.Coli) were found within standard value at Koyra (pond nos.1,3), Dumuria (pond nos.4,5,6), Rampal (pond no.3),Bagerhat city area (pond no.8) and Ashasuni (pond nos.4.5,6). Salmonella was found at Rampal (pond no.1) but Vibrio Cholerac in shrimp culture water Mongla (pond nos.4,5,6), were not found in any pond.Item Volumetric and Viscometric Studies Of Some Binary and Ternary Sodium Dodecyl Sulfate (SDS) Containing Alcohol System(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2010-12) Mia, Md. Abdul Hafiz; Motin, Dr. Md. Abdul.Densities and viscosities of binary mixtures of Methanol Propanol + Water and iso-Propanol + Water, Ethanol + Water, ii-0.005M and 0.01M aqueous SDS, Ethanol + 0.005M and 0.0IM aqueous SDS. n-Propanol ± 0.005M and 0.0IM aqueous SDS and iso-Propanol + 0.005M and 0.01M aqueous SDS have been studied over the entire range of composition (0 < X2 < + Water and ternary mixtures of Methanol I) at 298.15- 323.15K with an interval of 5K except methanol. Methanol system was studied at 298.15K, 303.15K and 308.15K The excess molar volumes, V' were calculated from the densities of the mixtures at different composition, showing minima at 0.45 mole fraction of Methanol, 0.4 mole fraction of Ethanol, 0.25 mole fraction of n-Propanol and 0.3 mole fraction of iso-Propanol. The VE for all the systems are negative over the entire range of temperatures. The values of values for the n-Propanol VE + Water and iso-Propanol + Water mixtures are sigmoids, being negative at lower mole fractions (X2) and positive at higher of Propanols. The magnitudes of the VL values of the mixtures are in the order: iso-Propanol X2 > Methanol Propanol. The observed values of V' for the mixtures have been explained in terms ofphysical, chemical, and geometrical contributions. The physical interactions, that is, nonspecific interactions between the real species present in the mixture, involve mainly dispersion force giving a positive contribution. The chemical or specific intermolecular interactions result in a volume decrease and these interactions include formation of hydrogen bonds and other complex-forming interactions. The structural contributions are mostly negative and arise from several effects, especially from interstitial accommodation and changes of free volume. The viscosity coefficients, il of all the above mixtures at all the six different temperatures have also been determined. Viscosities increase rapidly with alcohol concentration and show maxima in the water and aqueous SDS rich region at 0.2 - 0.3 mole fraction of alcohols. The position of maxima virtually does not change remarkably with the variation of temperature. the polar-polar mixtures, quite expectedly, show considerable deviation from ideal behavior. The excess viscosities, i/ values are found to be positive and large in magnitude, indicating that the aqueous and aqueous SDS solutions of alcohols are The hanol > ii-highly non ideal. All the curves pass through maxima in water and aqueous SDS rich region. The heights of the maxima are in the order:iso-Propanol + WaterPropanol + Water> Ethanol + Water> Methanol + The rapidly ascending part of viscosity curves in the dilute region of alcohols can be explained primarily in terms of the phenomenon called hydrophobic hydration, which assumes that, in water—rich region, the water molecules form highly ordered structures through hydrogen bonding around the hydrocarbon moieties of alcohols. The interaction parameter, have also been found to be positive in magnitude indicating strong solute-solvent interaction. The thermodynamic parameters such as, free energy (∆G#), enthalpy (∆H#) and entropy (∆S#) change of activation for the viscous flow of the binary and ternary systems are calculated for the entire range of composition by using Eyring's equation. The free energy (∆G#) were found to be positive in magnitude indicating that the kinetic species involved in forming cavities or holes in the liquid medium is given by the work required in forming the hole against surface tension of the solution. The excess properties (VE nE ∆GE) data have been fitted by the least square method to the four parameter Redlich-Kister equation and the values of the parameter a1 have been reported.The critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS) in water was determined from the conductance and viscosity measurement. They shows a sharp break in their values where micelle starts to form and is determined by extrapolating the data in premicellar region to intersect with a straight line drawn through the data in the post-micellar region.The estimated value of CMC was found to be 0.0085 mol.L -1 at 290C. The concentration of SDS in pre-micellar and post-micellar region of 0.005M and 0.0IM were used for the volumetric, viscometric and thermodynamic measurements. Although the value of density and viscosity of the studied systems in pre-micellar and postmicellar aqueous SDS solutions (0.005M SDS and 0.0IM SDS) are higher than the pure water solutions, but no appreciable change in the volumetric and viscomctric properties were observed by the addition of the surfactants.Item Studies on Chemical Effect and Feasibility of Biosensor for Arsenic Detection in Water.(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2011-06) Parveen, Shahnaz; Yousuf, Prof. Dr. Muhammad Abu220 water samples of different Arsenic (As) -affected areas in Bangladesh have been collected for analysis. Of them 58 samples were from Sagordari village of Jessore. 53 from Koyra village of Kolaroa, 56 from Hajigong village of Chandpur and 53 from Arihazar village of Narayangonj district. Various water quality parameters such as, p1-I, conductivity, chloride, iron content, hardness and dissolved oxygen were analyzed using standard analytical techniques. The suitability of investigated water for drinking and other purposes was also analyzed comparing with standard values. As content for the 220 different water samples have been perceived in there different methods, i.e., Merck field test kit, ARSOlux biosensor and ICP-MS methods. To find out an easy, low cost and environmentally friendly method for As content in ground water three different methods have been adopted. A comparison has been made among the three different test methods. Effect of different water quality parameters on As test methods has been analyzed. The p1-I range has been found to 6.2-8.1. It is seen that most of the samples i.e., 88.6% are alkaline while those of 10.5% are acidic and only 0.9% are neutral in nature. It is seen that only 4.5% samples have conductivity values with in the limit of drinking water range. Rest of the samples has high conductivity values. Of which 78.6% samples have the conductivity (cy) values of 0.5Item Preparation and Characterization of Alkylcarboxylate-Stabilized-Magnesium Nanoparticles(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2011-10) Rahman, Md. Hafizur; Yousuf, Prof. Dr. Muhammad AbuLong chain carboxylate shell stabilized magnesium (Mg) nanoparticles (NPs) were synthesized. In the core-shell type NPs the cores are Mg metal and the shells are long chain carboxylates. Synthesis of magnesium nanoparticles (Mg-NPs) involve: i) preparation of water soluble Na-salts of long chain fatty acids in alcoholic medium followed by ii) temperature controlled reaction with magnesium salts in aqueous medium in presence of suitable surfactant, poly vinyl pyrrolidone (PVP). The synthesis procedure used in this work was originally applied for the fabrication of long chain carboxylate capped magnesium nanoparticles. Structural and geometrical probabilities of prepared NPs were proposed on the basis of evidences from elemental analysis, optical and spectral studies. The compositions of the NPs were determined by elemental analysis. The experimental and calculated data for carbon (C), hydrogen (H), oxygen (0) and metal were compared. The presence and percentages of C, H and 0 revealed the presence of alkyl carboxylates and is proposed that these alkyl carboxylates act as protected shefls to the Mg-N Ps. From the titration of magnesium laurate, magnesium myristate, magnesium palmitate and magnesium stearate 7.83%, 7.02%, 6.54% and 5.93% Mg were found respectively. These values show that all the substances contain relatively higher amount of Mg than those of the molar ratio. These results exposed metallic Mg in the samples. It is proposed that this metallic Mg may be positioned at the core of the NPs. Melting point (MP) data also provide auspicious evidence about the formation of Mg-NPs. The Fourier Transform Infrared Spectroscopy (FTIR) spectra provide information about the presence of moisture or adhering free water and/or crystalline water and alkyl carboxylates in the NPs. Broad peak at —3040 to 3520 cm 1 appears due to 0-H stretching vibrations of hydroxyl (—OH) group. This may be due to the presence of moisture absorbed by the sample or water of crystallization. Two characteristic peaks at —1510 to 1600 cm 1 and at —1400 to 1510 cm1 were found and these may be due to C=O stretching and C-O stretching of carboxylates respectively. V Transmission Electron Microscopy (TEM) photographs showed the particles have the dimensions over a range of 25-90 nm. At higher magnifications, the NPs were recognized as spherical or oval in shape in all cases. The NPs are hygroscopic in nature as they absorbed 8.54-12.22% moisture. The moistures and/or crystallized water are also evidenced by the Differential Thermal Analysis (DTA) and Thermogravimetric Analysis (TGA) of the respective NPs. Both DTA and TGA demonstrated the presence of alkyl carboxylates or organic part in the NPs. The loss of organic parts at higher temperatures also corresponds to the decomposition of the NPs at higher temperature in a normal furnace as investigated by FTIR analysis.Item Studies on Volumetric and Viscometric Properties of Some Binary and Ternary Liquid Systems(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2011-11) Haque, Md. Fazlul; Motin, Dr. Md. AbdulDensities and viscosities of binary mixtures of Methanol +DMF, Ethanol +DMF, n-Propanol +DMF, iso-Propanol +DMF, n-Butanol +DMF, iso-Butanol +DMF, tert-Butanol +DMF, nAmyl alcohol +DMF, iso-Amyl alcohol +DMF and ternary mixtures of n-Propanol +0.02M SDS in DMF, n-Butanol +0.02M SDS in DMF and n-Amyl alcohol +0.02M SDS in DMF have been studied over the entire range of composition (0 n-Amyl alcohol> iso-Amyl alcohol>iso-Butanol>n-Butanol> iso-Propanol> n- Propanol> Ethanol> Methanol There is a marked decrease in the viscosity with increase of temperature for all the isomeric studied alcohols. At 298.15K, viscosity is found to be in the order: tert-Butanol> iso-Butano!>n-Butanol iso-Propanol> n-Propanol, which however changes to n-Butanol >iso-Butanol> tert-Butanol n-Propanol> iso-Propano! at 323.15K. This ascribed that the branched chain isomers are less stable than linear chain isomers at higher temperature and vice versa. The η E values are found to be positive or negative, indicating that the DMF solutions of alcohols are non ideal. Excess viscosities are negative at all the temperatures over the entire range of composition for all the systems except Methanol with minima occurring between 0.6-0.9 mole fraction of n-Propanol, iso-Propanol, n-Butanol, iso-Butanol, tert-Butanol, n-Amyl alcohol and iso-Amyl alcohol. Excess viscosity of Methanol is positive at all the temperatures over the entire range of composition and show maxima in the DMF rich region at 0.2-0.4 mole fraction of Methanol. Excess viscosity of Ethanol is negative and show minima at 0.4-0.5 mole fraction of Ethanol. The position of maxima and minima virtually does not change remarkably with the variation of temperature. The heights of the minima are in the order: tert-Butanol> n-Amyl alcohol> iso-Amyl alcohol—iso-Butanol>n-Butanol> iso-Propanol> n- Propanol> Ethanol. The negative VE, positive and positive interaction parameter e for the DMF Methanol system may be ascribed that the interaction is strong, namely formation of Fl-bonding between DMF and Methanol. The negative yE, negative ηE and negative E for the DMF + rest of the studied alcohols systems indicate that dispersion force is dominant. For the later case,P'E is negative due to the segmental inclusion of DMF in the interstices of polymolecular alkanol aggregates. Some disruptive force causing volume expansion may be present, but it is more than compensated for by volume contraction through the segmental inclusion of DMF. The thermodynamic parameters such as, free energy (∆GH), enthalpy (∆H'H) and entropy (∆SH) change of activation for the viscous flow for these systems were determined for the entire range of composition by using Eyring's equation. The free energy (∆GH) were found to be positive in magnitude indicating that the kinetic species involved in forming cavities or holes in the liquid medium is given by the work required in forming the hole against surface tension of the solution. The excess properties (yE, ηE∆GHE) data have been fitted by the least square method to the four parameter Redlich-Kister equation and the values of the parameter a1 have been reported. Although the value of density and viscosity of the studied systems of 0.02M SDS in DMF solutions are slightly higher than the pure DMF solutions, but no appreciable change in the volumetric and viscometric properties were observed by the addition of the surfactants.Item Investigation of Removal Characteristics of Heavy Metal Ions by Natural Adsorbents(2011-12) Golder, Harabilash; Yousuf, Professor Dr. Mohammad AbuRice husk, which is a relatively abundant and inexpensive material, is currently being used as the source of activated carbon an adsorbent for the removal of various pollutants from water. Activated carbon was prepared and characterized from rice husk. Rice husk was collected from local rice mill and used as raw material for producing activated carbon. Low-cost furnace was designed from locally available pottery and very slow burning of rice husk in presence of insufficient oxygen was applied for the preparation of activated carbon. The carbonized temperature and time was 350-550 C and about 3.0 hours respectively. The percentage of the yield in this method is about 25 (wt) %. Prepared activated carbon was characterized by a series of' experiments such as ash content, volatile content, moisture content, fixed carbon content, porosity and adsorption study. The prepared activated carbons contain 39.47% ash and 35.98% fixed carbon. SEM photographs exhibit that the prepared activated carbon possesses significant number of micropores, mesopores and macrospores. XRD analysis provides information that the prepared samples are amorphous in nature. All these observed properties indicate that the prepared samples might be used as good adsorbent.SEM photograph before and after adsorption clearly showed the evidence in favor adsorption. Prepared activated carbon used as potential adsorbent for methylene blue.Pb2+and Hg2+ in aqueous solution. Methylene blue showed maximum adsorption at pH 6.0. With increasing the sizes of adsorbents the extent of adsorption decreased at two investigated temperatures, 30 °C and 40 T. The equilibrium time for the adsorption was found to be about 180 minutes. Under all conditions amount of adsorbed increased with increasing the concentration of adsorbates. The experimental data have been found to be fit into Freundlich adsorption isotherm suggesting the chemisorption occurred. Both Pb2+and Hg2+ in aqueous solution showed maximum adsorption at pH 5.7 and 150 Rev/min shaking frequency. The equilibrium time for the adsorption in both cases were found to be about 180 minutes under all conditions and the amount of' adsorption increased with increasing the concentration of adsorbates. The experimental data have been found to be fit into Freundlich adsorption isotherm suggesting the chemisorptions occurred.Item Investigation Of Removal Characteristics Of Heavy Metal Ions By Natural Adsorbents(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2011-12) Golder, Harabilash; Yousuf, Prof.Dr. Mohammad AbuRice husk. which is a relatively abundant and inexpensive material, is currently being used as the source of activated carbon an adsorbent for the removal of various pollutants from water. Activated carbon was prepared and characterized from rice husk. Rice husk was collected from local rice mill and used as raw material for producing activated carbon. Low-cost furnace was designed from locally available pottery and very slo burning of rice husk in presence of insufficient oxygen was applied for the preparation of activated carbon. The carbonized temperature and time was 350-550 C and about 3.0 hours respectively. The percentage of the yield in this method is about 25 (wt) Prepared activated carbon was characterized by a series of' experiments such as. ash content, volatile content. Moisture content, fixed carbon content. porosity and adsorption study. The prepared activated carbons contain 39.47% ash and 35.98% fixed carbon. SEM photographs exhibit that the prepared activated carbon possess significant number of microspores. mesopores and macrospores. XRD analysis provides information that the prepared samples are amorphous in nature. All these observed properties indicate that the prepared samples might be used as good adsorbent. SEM Photograph before and after adsorption clearly showed the evidence in favor adsorption. Prepared activated carbon used as potential adsorbent for methylene blue. Pb2+and Hg2+ in aqueous solution. Methylene blue showed maximum adsorption at pH 6.0. With increasing the sizes of adsorbents the extent of adsorption decreased at two investigated temperatures, 30 °C and 40 T. The equilibrium time for the adsorption tas found to be about 180 minutes. Under all conditions amount of adsorbed increased with increasing the concentration of adsorbates. The experimental data have been found to be fit into FreundIich adsorption isotherm suggesting the chemisorption occurred. Both Pb2+ and Hg2+ in aqueous solution showed maximum adsorption at p1-I 5.7 and 150 rev!miii shaking frequency. The equilibrium time for the adsorption in both cases were found to be about 180 minutes under all conditions and the amount of' adsorption increased with increasing the concentration of adsorbates. The experimental data have been found to be fit into Freundlich adsorption isotherm suggesting the chemisorption occurred.Item Study on the Physico-Chemical Parameters Present in Shrimp and Shrimp Culture Water for the Improvement of Sea-food Quality of Khulna Region, Bangladesh(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2011-12) Ahamed, Mir. Md Fakker Uddin Ali; Aziz, Dr. Md. AbdulThis research provides guidance on how to develop shrimp quality in aquaculture. Aquaculture development is growing rapidly worldwide due to increasing demands of its products and limited production from Inland and marine capture fisheries. The research studied water of different sources which are used in shrimp culture. The results provided significant information and the values were compared with the current standard values or acceptable physico-chemical factors that affect the quality of shrimp culture water as well the quality of shrimp. The current state of knowledge on the acceptable limits of hazardous chemicals in water used for fisheries and aquaculture and the acceptable concentrations accumulated in the tissue of aquaculture products are also furnished. Shrimp and shrimp culture water were collected and tested from different locations or shrimp farms (Ghcrs). hatcheries and nurseries of Bagerhat, Satkhira and Khulna district. The farms were chosen and designated as 1-9 from Satkhira. 10-1 8 from Khulna and 19-27 from Bagerhat. Different parameters such as, pH, DO, BOD, Fe, salinity, hardness, turbidity and heavy metals were performed. DO, BOD, pH and salinity were measured on the spot after collecting the shrimp culture water from shrimp farms (Ghers), hatcheries and nurseries. Turbidity, hardness. NO3 and Fe were measured in the laboratory with spectrophotometer (DR-4000) in Fisheries office, Khulna. Heavy metals were measured atomic absorption spectrophotomer in atomic energy center. Dhaka. Bangladesh. The values of pH, BOD, salinity and hardness at different location of' Bagerhat were found within standard limits in furms nos. 19 to 27 but DO was found to be high. The values of BOD and iron at different location of Khulna were found within standard limits in farms 10 to 18 but pH, turbidity, salinity, hardness, and DO were found to be high. The values of hardness, BOD and iron at different location of Satkhira district were found within standard limits in farms nos. I to 9 but pH, turbidity, salinity, and DO were found to be high. The values of nitrate in all farms at Satkhira, Khulna and Bagerhat district were low. The heavy metal such as Pb, Cr, Cd and Hg in shrimp culture water were found within standard limit in Satkhira district in farms nos. 1, 4 and 7 and heavy metal in shrimp were found within standard limit in farms nos. 1 to 9. The values of heavy metal Pb in shrimp for shrimp in farms nos. 11, 12,14, 15, 1 7 and 18 of Dumuria, Koyra and Paikgachha of Khulna district were found within standard limit but in farms nos. 10, 13 and 16 were high. The value of Hg in shrimp culture water for shrimp farms of Dumuria, Koyra and Paikgachha of Khulna district were found in farms nos. 10 to 18 within standard limit. The value of Cd in shrimp culture water for shrimp farms of Dumuria. Koyra and Paikgachha of Khulna district were found in farms nos. 10, 12,14,15,17 and 18 within standard limit but in farms nos. 11, 13 and 16 were higher than standard limit. The value of Cr in shrimp culture water for shrimp farms of Dumuria, Koyra and Paikgachha of Khulna district were found in farms nos. 10, 11, 12, 14, 15, 17 and 18 within standard limit but in farms nos. 13 and 16 were higher than standard limit. The values of heavy metals Pb, Hg, Cd, and Cr in shrimp for shrimp farms of Rampal, Mongla and Bagerhat main town of Bagerhat district were found within standard limit in farms nos. 19, 20, 21, 22, 23, 24, 25, 26 and 27. The quality of physico-chemical parameters in shrimp culture water at different locations at Bagerhat was found to be standard and the presence of heavy metals in shrimps at these locations was found to be within standard limit. The physico-chemical parameters such as pH, salinity, hardness. DO, BOD, NO3- Fe and heavy metals in shrimps and shrimps culture water of other areas should be maintain as like as Bagerhat.Item Study of the Effects of Electrolytes on the Carbohydrate Solutions with Volumetric and Viscometric Measurements(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2012-11) Alam, Sheikh Ahidul; Motin, Dr. Md. AbdulIn this study, a simple volumetric and viscometric method was used for the analysis of effect of body containing electrolytes such as NaCl and KC1 on the carbohydrates (glucose, sucrose and maltose) solution. The densities and viscosities of NaCl and KCI at different concentration in aqueous and aqueous glucose, aqueous sucrose and aqueous maltose (1% (w/v), 5% (w/v) and 10% (w/v)) solutions have been determined at 298.15, 303.15, 308.15, 313.15, 318.15 and 323.15 K respectively. The studied electrolytes are found to be dissolved readily in aqueous and aqueous carbohydrate (upto 10% (w/v)) solutions. The density of glucose, sucrose and maltose in aqueous solution were found to be order of Maltose > Sucrose > Glucose. The value of density of NaCl and KCI increases with the increasing of molarity of the electrolytes. Densities of electrolytes in aqueous carbohydrate solutions are concentration of electrolyte can be attributed to solute-solvent interaction. The apparent molar volumes, ɸv were obtained from these densities data. The limiting apparent molar volumes, ɸºv and experimental slope, Sv derived from Masson equation have been interpreted in terms of solute- solvent interactions. The sign of --- i.e. second [(∂^2 〖 Ø v 〗^ )/(∂〖 T 〗^2 )]P derivative of limiting apparent molar volume of solutions with respect to temperature at constant pressure which corresponds to structure making or breaking properties of solutes were determined. NaCl in water, 1% (w/v) glucose and 1% (w/v) maltose solution, the value of [(∂^2 〖 Ø v 〗^ )/(∂〖 T 〗^2 )]P were found to be slightly positive suggesting structure making property. In case of sucrose it shows negative value of [(∂^2 〖 Ø v 〗^ )/(∂〖 T 〗^2 )]P for all the electrolytes containing solvent systems indicating structure breaking property. KCI in water and carbohydrate solution, the values of [(∂^2 〖 Ø v 〗^ )/(∂〖 T 〗^2 )]P were found to be negative suggesting structure breaking tendency. The viscosity vs molarity plots for all the electrolytes systems are linear in all the solvent systems with some exceptions. The viscosity, ƞ for all the studied electrolytes are greater in aqueous carbohydrate solvent system than those in water system. The viscosities coefficients A and B were determined from viscosities data on the basis of Jones Dole equation. The coefficient B gives information regarding solute - solvent interaction and shape and size effect on the solvent structure. The coefficient A represents the ion-ion interaction. The B-coefficient for NaCl in aqueous and aqueous glucose, aqueous sucrose and aqueous maltose solutions (1% (w/v)) at all the temperatures are positive. The positive value of the B-coefficient corresponds to the structure making behavior of solutes. The B-coefficient for KC1 in water and carbohydrate solutions (1%, 5% and 10% (w/v)) are negative. The negative value of B-coefficient corresponds to the structure breaking behavior of KCl. The sign of dB/dT corresponds to structure making or breaking properties of solutes, were determined. For NaCl in aqueous and aqueous carbohydrates (1% (w/v)) solutions, the values of dB/dT are negative which corresponds to structure making behavior. For aqueous and aqueous carbohydrate solution (1%, 5% and 10% (w/v)) of KC1, the values of are positive which corresponds structure breaking behavior.The free energy of activation, ΔG≠ for viscous flow was calculated using Nightinagle and Benck equation at the experimental conditions. Activation enthalpy, ΔH≠ and activation entropy, ΔS≠ were calculated using the Eyring equation and other thermodynamic relations. The effects of electrolytes on the structure of water and aqueous carbohydrate solutions were interpreted in terms of apparent molar volumes, viscosities and viscosity coefficients (A and B) values and thermodynamic parameters (ΔG≠, ΔH≠, ΔS≠).Item Study on Quality Changes of Fresh Water Prawn(Galda) in the Shrimp Change Value(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2012-12) Chakrabortty, Anupam; Aziz, Prof. Dr. Md. AbdulThe present study was conducted to assess the quality loss of shrimp (Macrobracium rosenbergii) known as Galda in the value chain of Bagerhat region. The investigation was canied out in December 2011 to February 2012. The study was undertaken in twelve selected shrimp farms, four faria, four depot and five factory receiving point of different locations, viz. Fakirhat, Bagerhat Sadar, Mollahat and Sharankholla in Bagerhat region. Quality assessment included proximate analysis of Protein parameters and Biochemical {Total Volatile Base Nitrogen (TVB-N) and Trimethylamine Nitrogen (TMA)}. The TVB-N and TMA were determined by using Conway's Micro-diffusion Technique and Protein was determined by proximate analysis (kjeldhal method in wet way). Protein contents of forty eight samples were found in the range of 17.68% to 24.05% in wet weight method. At the farm level, the protein content was 23.17%, 23.80%, 23.01% and 23.16% in Fakirhat, Bagerhat Sadar, Mollahat and Sharankholla station in Bagerhat region respectively. At factory receiving point, protein content was 18.55%, 18.91%, 18.17% and 18.82% in Fakirhat, Bagerhat Sadar, Mollahat and Sharankholla station in Bagerhat region respectively. Protein loss of Shrimp was being 19.94%, 20.55%, 20.03% and 18.74% respectively in Fakirhat, Bagerhat Sadar, Mollahat and Sharankholla from farm to factory receiving point. From farm to factory receiving point, grand protein loss was 19.82%. The TVB-N value was found from 10.14 mg/100g to 19.54 mg/100g. The TMA value was found from 7.37 mg/l00g to 16.75 mg/100g. The results obtained from this research will help the shrimp's exporter to export good quality shrimps.Item Study of the Effects of Acetonitrile on the Alcohol Solutions by Volumetric and Viscometric Measurements(2013-02) Monoranjan, Mondal; Motin, Dr. Md. AbdulDensities and viscosities of binary mixtures of n-Propanol + Acetonitrile, iso-Propanol + Acetonitrile, n-Butanol + Acetonitrile, iso-Butanol + Acetonitrile n-Pentanol + Acetonitrile, iso-Pentanol + Acetonitrile and Propylene glycol + Acetonitrile have been studied over the entire range of composition (0 < x2 < 1) at 298.15- 323.15K with an interval of 5K. The studied alcohols or glycols are found to be dissolved completely in acetonitrile solutions at any composition. The density of alcohols or glycols in equi molefraction of acetonitrile solution was found to be order of Propylene glycols> iso-Pentanol> n -Pentanol > n-Butanol> iso-Butanol > n -Propanol > iso-Propanol. The value of density of alcohols in acetonitrile increases with the increasing of composition of the alcohols. The increase of density with composition of alcohols can be attributed to solute-solvent interaction. The densities of all alcohols increase with the increase of carbon number which may be depend on the molecular weight of alcohols, structural formula and H-bonding of lcohols. The density of Propylene glycol is higher than the studied alcohols owing to the higher degree of —OH and increasing unsaturation. The densities decrease regularly with the increasing of temperature. This is due to the thermal agitation and hence the weaker the dipole-dipole interaction or dissociation of H-bonding are occurred. The excess molar volumes, VE were calculated from the densities of the mixtures at different temperatures. The values of VE for all the systems are positive over the entire range of composition, showing maxima ~ 0.1-0.2 mole fraction of n-Propanol and ~ 0.4 mole fraction of iso-Propanol, ~ 0.4 mole fraction of n-Butanol ~ 0.4 mole fraction of iso-Butanol, ~ 0.3- ~ 0.4 mole fraction of n-Pentanol, ~ 0.5 mole fraction of iso-Pentanol and ~ 0.5 mole fraction of Propylene glycol . The excess molar volume, VE of alcohols in acetonitrile solutions was found to be order of Propylene glycol >n-Pentanol >n-Butanol >n-Propanol and iso-Pentanol > n-Pentanol and iso-Butanol > n-Butanol and iso-Propanol > n-Propanol. The increasing of VE with carbon chain length of alcohol may be related to increase of the size of alcohols. The values of VE for the studied alcohols increase with the increase of temperature. The observed values of VE for the mixtures have been explained in terms of physical, chemical and geometrical contributions. The viscosity coefficients, n of all the above mixtures at all the six different temperatures have also been determined. The viscosities increase initially slowly up to ~ 0.6 mole fraction of n -Propanol, iso-Propanol, n-Butanol, iso-Butanol, n-Pentanol, iso-Pentanol and Propylene glycol and later on, the viscosity increases sharply until the pure alcohol is reached specially at lower temperature. In pure state the viscosity of alcohols has been found to be in the order of, propylene glycol > iso-Pentanol n-Pentanol > iso-Butanol > n-Butanol > iso-Propanol > n- Propanol There is, a marked decrease in the viscosity with increase of temperature for all the studied alcohols. This ascribed that the alcohol solutions are less stable at higher temperature. The increasing of viscosity with carbon number of alcohols ascribed that the solution resistance increases with the increase of carbon chain length. The linear dependence of In77 against 1/T shows for the all studied alcohols. The branched chain isomers are less stable than linear chain isomer at higher temperature. The excess viscosity, ƞE values are found to be negative, indicating that the acetonitrile solutions of alcohols are non ideal. Excess viscosities are negative at all the temperatures over the entire range of composition for all the systems with minima occurring between 0.6-0.9 mole fraction of n-Propanol, iso-Propanol, n-Butanol, iso-Butanol, n-Pentanol, iso-Pentanol and Propylene glycol. The negative excess viscosity, ƞE of acetonitrile + all the studied alcohols indicate that the dissociation of components through dispersive forces or steric hindrance. The position of minima virtually does not change remarkably with the variation of temperature. The values of the minima are in the order: Propylene glycol ~ iso-Pentanol > n-Pentanol> iso-B utanol>n-Butanol > iso-Propanol> n-Propanol The hydrophobic effect increases with the increasing of carbon chain length of alcohols. This indicates that the ƞE decreases with the decrease of carbon number. The positive VE, negative ƞE, and negative ε for the acetonitrile + studied alcohols systems indicate that dispersion force is dominant. Some disruptive force causing volume expansion may be present and it is more than compensated by volume contraction through the segmental inclusion of acetonitrile. The thermodynamic parameters such as free energy (ΔG*E), enthalpy (ΔH*) and entropy (ΔS*) change of activation for the viscous flow for these systems were examined for the entire range of composition. The free energy (ΔG*) were found to be positive in magnitude indicating that the kinetic species involved in forming cavities or holes in the liquid medium is given by the work required in forming the hole against surface tension of the solution. The negative excess free energy, ΔG*E indicate that the strong dispersion force in alcohols-acetonitrile solution is dominant. The excess properties (VE, ƞE, ΔG*E) data have been fitted by the least square method to the four parameter Redlich-Kister equation and the values of the parameter ai and standard deviation have been reported. The volumetric properties are fully consistent with viscometric and thermodynamic properties.Item Adsorption Properties of Mahogani (Swietenia Mahogani) Leaf Powder: Removal of Acid Dyes from Aqueous Solution.(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2014-04) Akther, Meghla; Badal, Dr. Md. Mizanur RahmanThe Mahogani (Su'itenic, Mahogani) leaf treated with used as an adsorbent for the sulphuric acid and !'formaldehyde were removal of Reactive yellow C8G and Reactive red MSB de from aqueous solution. The adsorption characteristics of reactive dyes on activated Mahogani leaf powder (MLP) were evaluated as a function of p1-I, adsorbent dose and initial concentration of adsorhate. The amount of dye adsorbed per unit weight of the adsorbent increased with the increase of concentration and contact time. The adsorption was favored by an acidic p1-I range for Reactive red but not significant change for reactive yellow dyes. The adsorption processes were best described by a second-order rate equation. Reactive Yellow and Reactive Red dyes adsorption on MLP agreed with both Langmuir and Freundlich isotherms. The isotherm plots showed that the Freundlich equation gave slightly better linearity than the l.angmuir equation (R 0.94 for Langmuir plots; R 0.99 for Freundlich plots) indicating the MLP surfoce to be heterogeneous in the long range, but having some amount of uniformity locally. Langmuir monolayer adsorption capacity ((1ni) decreased from 67.11 to 11 .93 mg/g br reactive vehlo\v and from 12.39 to 2.09 mg/g for reactive red. MLP amount varying from 0.5 to 1.0 g/L. Ihe adsorption equilibrium parameter, for reactive yellow. h. varied from 0.028 to 0.034 L!mg with the increase in MLP amount and similar trend observed for reactive red. 'l'he adsorption capacity, k fshowed a decrease from 143.52 to 19.76 L/g with increase in MLP amount Irom 0.5 to 1.0 g/L, Similar results found for reactive red dye. The adsorption affinity. 11. lies between 0.21 and 0.27 satisfying the condition a < I for favorable adsorption.Item Study on Physico-Chemical Properties of Rain Water, Ground Water and Pond Water in KUET Premises(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2014-05) Rahman, Md. Aminur; Badal, Dr. Md. Mizanur RahmanSix samples of pond water, four samples of rain water and four samples of ground water were collected from the KUET premises. The sampling of pond water has been made during the period Nobember, 2013 to April 2014, while the rain water samples were collected during the late rainfall in the month of September. The rain samples were mounted 1.5 meters above the ground to avoid rain splash as recommended Pond water samples were collected by grab-sampling method. All sample's were filtered and preserved at 200 C. Some water parameters such as Alkalinity, Hardness, TDS, Arsenic, pH, Turbidity, Conductivity & Salinity were measured. Four tube well water samples were collected from different location of KUET residential area. The pH of tube well water ranged from a minimum of 7.79 to a maximum of 8.2 of TW3 (Tube well water, collected from building no 12) and 1W1 (Tube well water, School gate KUET) respectively. Similarly the variation of pH of pond water ranged from a minimum of 8.40 to a maximum of 8.87 of PWL1 (Pond water lower Position, Rokaya hail) and in rain water the maximum value was 6.77 of RWJ1 (Rain water from jessore urban) and the minimum value was 6.34 of RWC (Rain water collected from Chittagong) respectively. The values of conductivity for all tube well water were found to be greater than those of pond water and rain water. In present observations the conductivity for tube well water ranges from 1021 to 1598 ts/cm, for pond water ranges 324 to 732 p.s/cm and for rain water ranges from 13 to 80 J.ls/cm. It indicates that the tube well water contain larger quantity of dissolved mineral salts. In case of pond water, the conductivity is also significantly change during winter season and rainy season. The total dissolved solids (TDS) of tube-well water ranged from a minimum of 551 rng!L to a maximum of 887 mg/L of TW1 (Tube-well, School gate) and TW4 (Tube well water,collected from building no 19) respectively. Similarly the variation ctotal dissolved solids of pond water ranged from a minimum of 175 mg/L to a maximum of 399 mg/L of PWL 1 (Pond water, lower Position Rokaya hail) and PWL2 (Pond water, lower Position power plant side pond) and for rain water ranged from a minimum of 6 mg/L to a maximum of 40 mg/L of RWC (Rain Water, Collected from Chittagong) and R\VK (Rain Water, Collected from Khulna) respectively. This high values of TDS (Total dissolved solids) specially in Tube well water are mainly due to carbonates, bicarbonates, chlorides, phosphates and nitrates of calcium, magnesium, sodium, potassium and manganese. The variation in total alkalinity of tube-well water ranged from a minimum of 496.66 mg/L to a maximum of 508.33mg!L of TW2 (Tube well water, collected from building no 5) and TW3 (Tube well water, collected from building no 12) respectively . Similar variation in total alkalinity of pond water ranged from a minimum of 83.33 mg/L to a maximum of 131.66 mg/L of PWL1 (Pond water, lower Position Rokaya hail) and PWU3 (Pond water, collected from upper Position Khan Jahari Ali Hall) respectivcly. Tube-well water samples have found the iron content and the results varied from 16.78 27.97 ppm. No tube-well was found having the iron content within the maximum permissible limit of 1.0 ppm. Lead and cadmium concentration in the rain water was found below the detectable limit. Arsenic was investigated to all tube well water and found below 0.02 ppm that is within acceptable limit.Item Study on Water pollution of Vairab River from Nowapara, Jessore to Labon Chara, Khulna(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2014-05) Ahmed, Firoz; Aziz, Prof. Dr. Md. Abdulonly Vairab river is the vital source of water in Nowapara, Jessore to Khulna and is being polluted increasingly by effluents discharged from industries, municipal sewage, household wastes, linical wastes and oils. The purpose of this study is to investigate the impact of this wastewater on the river and thus to provide an updated report on the state of water quality of river Vairab. The water sample were collected from different areas in the river Vairab and analyzed for physico-chernical parameters and fresh water elements in the month of July, 2013 to November, 2013. The values of Temperature, turbidity, pH, chloride, hardness, DO, BUD, COD, Fe, As, Pb. Cd and Measured. During study period the temperature. turbidity,pH, hardness, chloride, DO, BUD and COD were found to be 28 Cr in the river °C to 31.5°C. 37 to 947 NTU, 7.2 to 8.01, 92 to 140 ppm, 9 to 34 ppm, 122 to 5.51 mg/L, 0.22 to 5.79 and 3.80 to 10.80 mg/L respectively. The concentration of Fe, Pb, As, Cd and Cr were found to be 0.10 to 2.60 ppm, 0.004 to 0.025 ppm, 0.001 to 0.004 ppm, 0.00015 to 0.0094 ppm and 0.001 to 0.006 ppm respectively. From the results of investigation, it was observed that the values of pH, Cl, hardness, As, Pb, Cd and Cr were within standard limit but the values of temperature, turbidity, DO, BUD, COD and Fe were not within acceptable limit as recommended by WHO and BDS guidelines. The results obtained from this investigation will help the people of the research area to be conscious for using the water in the Vairab river.Item Synthesis, Characterization and Biological Evaluation of Mixed Ligand Complexes of Pt(IV), Pt(II) and Pd(II) Ions Containing Dibasic Acids and Heterocyclic Amines(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh, 2014-06) Hossain, Md. Belayet; Yousuf, Prof. Dr. Mohammad AbuMixed ligand complexes of dibasic acid and heterocyclic amine with transition metal ions have been synthesized and characterized. Research was devoted to the synthesis and characterization of mixed ligand complexes of Pt(II), Pt(IV) and Pd(II) ions with some dibasic acid (viz., malonic acid, oxalic acid and phthalic acid) as primary and heterocyclic bases, (viz., quinoline (Q), iso-quinoline (IQ), pyridine (Py), 2-aminopyridine (2apy) and 4-picoline (4-pico) as secondary ligands. The general formula of the complexes are as follows; [MLL1] (where M = Pt(IV) (1-8), Pt(II) (13), Pd(II) (9-12,14-17); L=2C3H2O4, malonato (1-4), 2C2O4, oxalato (5-8), C8H4O4, phthalato (9-13), oxalato C2O4(14-17); and L1 =2C9H7N, quinoline (1, 5, 9, 14), 2C9H7N, iso-quinoline (2, 6, 10,15), 2C5H5N, pyridine (3, 7, 11, 16) , 2C6H7N, 4-picoline (4, 8, 13), C5H6N2, 2-aminopyridine (12, 17)). Complexes were characterized by elemental analysis, conductivity, magnetic measurement, infrared and electronic spectroscopic studies. All the complexes were isolated in the ethanolic solution as amorphous solid. All the synthesized complexes are colored. The complexes, all were slightly soluble in water and methanol but are readily soluble in DMF and DMSO. Single crystal of the complexes could not be isolated from any solution. The conductance values of the complexes were in the range (10.35-12.85) Ω-1 cm2 mol-1 indicated that these complexes were non-electrolyte in nature. Melting points of the complexes were in the range 240 to 270(± 5°C) while those of the ligands were -15 to 211 (± 5°C) which indicate the strong indication of coordination of the ligands and formation of the complexes. The ν(OCO)asym mode of Pt(IV), Pt(II) and Pd(II) complexes of oxalato, malonato & phthalato is found as a very strong-to-strong band at 1575.7-1708.9 cm-1, and the corresponding ν(OCO)sym one is exhibited at 1363.6-1410.9 cm-1 Two ν(OCO) stretching symmetrical and asymmetrical lie lower than the free ion values and the frequency difference between these two modes is 198-317 cm-1. From the frequency difference it is evident that the carboxylate group acts as a monodentate ligand. Further, the presence of MO (O = Oxygen in deprotonated dibasic acid) bonding is evident from the appearance of vM-O modes at 500.0-557.4 cm-1 in the spectra of the complexes. The presence of M-N bonding in the complexes is evident from the appearance of VM-N modes at 421.4-476.4 cm-1. Shifting of infrared spectra of aminopyridine to ~3320.2-3345.3 cm-1 and 3056.0-3061.8 cm-1 in the mixed ligand complexes is indicated the coordination through amino nitrogen to the metal ions. By comparing the data of elemental analysis, magnetic moment, spectroscopic analysis the proposed empirical formula of the synthesized complexes can be following: [Pt(MA)2(Q)2](1), [11t(MA)2(IQ)2](2). [Pt(MA)2(Py)210)), [Pt(N4A)(4-pico)2](4), [Pt(OX)2(Q)21(5), [Pt(OX)2(IQ)2](6), [1't(OX)2(Py)21(7), [Pt(OX)2(4-pico)2](8), [Pd(Ph)(Q)2](9), [Pd(Ph)(1Q)]( 10), [Pd(Ph)(Py)21( 11), [Pd(I'h)(2-apy)J( 12), [Pt(Ph)(4-pico)21( 13), [Pd(OX)(Q)2J( 14), [Pd(OX)( IQ)21( 15), [Pd(OX)(Py)21( 16) and [Pd(OX)(2-apy)](17) where, MA = Deprotonated malonic acid, OX = Deprotonated oxalic acid, Ph = Deprotonated phthalic acid, Q = quinoline, IQ = iso-quinoline, Py = pyridine, 4-pico = 4-picoline, 2-apy = 2-aminopyridine. The magnetic moment values of the complexes indicated that these complexes are diamagnetic. This diamagnetism is supported by the small negative values obtained for their magnetic susceptibility. The electronic spectra of the Pt(IV) complex gave three bands at 36,000, 39,650 and 41,000 cm-1 corresponding to the transitions 1Aig → 1Tig1g, 1Aig1g → 3T1g and 1A1g → 1T2g. In addition to the d-d transitions, the Pt (IV) complexes obtained two charge transfer bands at 39000 and 50000 cm-1 The electronic spectra of the Pd (II) complex showed three spin allowed d-d transitions and two charge transfer bands. The bands were obtained at 22203-23055, 28155-28500, 3 1000-31350, 34500-35005 and 40000-40205 cm-1 corresponding to the transitions 1A1g → 1A2g, 1A1g → 1B1g, 1A1g → 1Eg, 1A1g → 1A2u and 1A1g → 1Eu respectively. The Pt(II) complex gave three bands at 36000, 39650 and 41000 cm-1 corresponding to the transitions 1A1g → 1B1u, 1A1g → 1Eu, and 1A1g → 1A2u respectively. Electronic spectra and magnetic measurement confirmed that Pt (IV) (1-8) complexes are octahedral structure and Pt (II) (13) & Pd (II) (9-12, 14-17) complexes are square planar structure. From the antibacterial screening it is seen that all complexes have antibacterial activity against Gram-positive (Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis) and Gram-negative (Pseudornonas aeruginosa, Salmonella bovismorbificans, Salmonella typhi, Escherichia coli) bacteria through disc diffusion method. Complexes [Pt(MA)2(4-pico)2} showed the highest antibacterial activity against all bacteria tested. The complexes 1, 6 and 11 showed the lowest inhibition zones against Staphylococcus aureus, Listeria monocytogenes & Enterococcusfaecalis corresponding to zone sizes of 8, 11 and 10 mm respectively. The complexes 2, 7 & ii exhibited no zone inhibition against Staphylococcus aureus, Salmonella typhi and Salmonella bovismorbificans. All the synthesized complexes have shown mild to moderate antibacterial activity. The highest and the lowest activities were found in complex 4 and complex 11 respectively.Item Electrochemical Characterization Of Biologically Important Electroactive Metal Ligand Complexes With Multi-electron Transfer Reactio(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2014-07) Rahman, Md. Matiar; Motin, Prof. Dr. Md. AbdulThe redox behavior of Cu (II) only and Cu (II) with aspartic acid (Apa), L-phenl alanine (Phe), 3-nitrobenzene sulfnate (NBS) ; Zn(II) only and Zn(ll) with Apa, Phe, NBS and Catechol ((ate) has been studied Cyclic voltammetry (CV), Differential pulse voltammetry (DPV) and Chronamperometry (CA) techniques. The voltammetri technique demonstrates the interaction of biologically important metals (Cu, Zn) with the ligands (Apa, Phe, NBS, Cate) that is formed of metal-ligand complexes. The interaction studies have been carried out in variation of metal ion concentration, ligand concentration, Buffer solution of different pH and scan rate. In all the studies of Cu(II) and Zn(II) complexes, with some exception, Cu(II )-ligand systems and Zn(II)-ligand systems have been found to undergo quasireversible electrode reaction with EC mechanism. For all the ligands, Apa and Phe are electroinactive ligands whereas Cate and NBS are electroactive ligands. Both the anodic and cathodic voltamnietric peaks were shifted and sometimes developed new peaks with the addition of Apa, Phe, NBS, Cate in Cu(II) and Zn(II) solutions. On the addition of Apa, Phe and NBS in Cu(II) solution, the peak positions of the voltammogram of Cu(II)-Apa, Cu(II)-Phe and Cu(II)-NBS, first anodic peak was shifted positively but the second oxidation peak was shifted negatively with respect to that of only Cu ( II). The peak current decreases significantly compared with that for free Cu(II) in the same experimental conditions, This behavior confirms the interaction and complexation between Cu(II) and Apa, Phe. The effect of pH of Cu(II)-Apa, Cu(II)-Phe and Cu(II)-NBS were studied by varying pH from 3.5 to 7.0. The peak current of Cu(II)-Apa, Cu (II)-Phe and Cu(II)-NBS increases with the decrease of pH indicating that at lower pH the Cu(II)-Apa, Cu(II)-Phe and Cu(II)-NBS is highly electroactive. The maximum peak current was obtained at pH 3.5. This shows that the electrochemical oxidation of Cu(II)-Apa, Cu(II)-Phe and Cu(II)-NBS is aicilitated in acid media and hence the rate of electron transfer is faster.The average diffusion coefficient, D of Cu(II)- Apa or Cu(II)-Phe is found to he 4.5 x l0-6cm2s-1. The cyclic voltammogram of Zn(II) only and Zn(II) with Apa, Phe, NBS and Cate in aqueous and in buffer solution of different pH were taken at different scan rates. The CV of Zn (II) shows at pH (1 .5, 3 and 4.5) one well defined anodic and cathodic peak at different scan rate hut in aqueous solution only Zn(II) showed very weak anodic peak. Upon the addition of Apa, Phe, NBS, Cate with Zn(II) the first anodic peak shifted positively and the cathodic peak is shifted negatively which indicates the formation of Zn (II)-Apa or Zn ( II)- Phe complex. The intensity of the anodic and cathodic peak current decreases with the increasing of Apa or Phe or NBS or Cate suggesting that is formed of more Zn( 11 )-Apa or Zn(II)- Phe or n(ll)- NBS complex. The effect of pH of Zn(II)-Apa, Zn(II)-Phe, Zn(II)-N BS and Zn(II)-Cate were studied by varying pH from 1.5 to 11. The peak current decreases with the increase of pH .The maximum peak current was obtained at pH 3-4.5.At higher pH(7-11), the anodic peak disappeared. This shos that the electrochemical oxidation of Zn(II) complexes is hindered in basic media. For the comparison CV of Zn(II) only and Zn( II) —Asp, Zn(II)-Phe, Zn( II)- Cate, Zn( II)-NBS at similar condition (pH 3, scan rate 0.1 V/s). it is seen that the anodic peak current of Zn(II)-Asp and Zn(II)-Phe are lower than that of Zn(II) only hereas the anodic peak current of Zn(II) - Cate and Zn(II)-NBS is higher than that of Zn(II) only. When Cate and NBS are coordinated with Zn(II) both metal and ligands are electroactive, So constructive interference of peak appeared whereas Asp and Phe are coordinated with Zn(II), here ligands are eleciroinactive so the overall peak currents are lower than Zn(II) only. The slopes of the plots of Ep against pH of all studied metal ligand complexes ere determined graphically as anodic peak 25- 35 mV/pH at 0.1 V/s, which is close to the theoretical value of 30 mV for a two-electron, two-proton transfer process which indicates that the oxidation of all metal-ligand complexes proceeded via the 2e-2H+ processes. This suggests that during the reaction not only electron but also protons are released from the metal-ligand complexes. For all the studied system, with the increasing of metal: ligand composition from 1:1 to 1:5 (metal fixed), the current decreases linearly but after more addition of ligands, the current intensity change is constant. This indicates that the availability of metal is limited for the formation of the metal-ligand complex at saturation point. When the composition of metal increases with the fixed of the composition of ligands from 1:1 to 5:1. after certain concentration, the voltammogram pattern reflected into the only metal, because of the deficiency, of ligands in solution. The relation between metal - ligand concentration and cyclic voltammetric anodic and cathodic peak current (Ipaand Ipc) is linear. The proportionality of the anodic and cathodic peak currents with square root of scan rate of all the studied metal ligand complexes with few exceptions suggests that the peak current of the difièrent complexes at each redox reaction is controlled by diffusion process. From the studied of all systems it is seen that current functions (1/v-1/2) decreased with the increasing of' scan rate except Zn(II)- Cate. So the behavior of electrode reaction of all Cu(II)- ligands and Zn(II)- ligands are of ECE mechanism except Zn(II)- Cate is of CE mechanism.Item Volumetric and Viscometric Studies on the Long Chain fatty acid in Surfactant Stabilized Propanol(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2015-01) Salam, Md. Abdus; Yousuf, Prof. Dr. Muhammad AbuVolumetric and viscometric studies of binary mixtures of (fatty acid + propanol) and ternary mixtures of (fatty acid + propanol + surfactant) were done. Lauric, palm tic and stearic acids were taken as fatty acids while the surfactant was sodium dodecyl sulfate (SDS). The investigated binary and ternary systems were carried out over a concentration range of 0.0100-0.4000 M of fatty acids at 298.15 to 323.15 K at 5 K intervals. The SDS concentrations were 0.001 M and 0.005 M. The apparent molar volumes, φv. of both binary and ternary mixtures were determined from the densities of the mixtures. The φv, values have been found to be positive throughout the whole concentration range for all acids in propanol. The apparent molar volumes, .co. of all fatty acids in propanol were found to be increased with concentration at all temperatures.SimilarlyφV, values were found to be increased with increasing temperature at any concentration of the solution. These results may be due to the solute—solvent and solute—solute interaction in the solutions. This shows that φ, values are strongly dependent upon concentration as well as the temperature. The φv values are also found to be increased with the chain length of the fatty acids and this may be due to the hydrophobic characters of alkyl chain. The number of carbon atoms in the hydrocarbon chain of the fatty acid is proportional to the degree of hydrophobic/hydroPhilic balance of the whole compound. Eventually the pattern of apparent molar volumes of laurie, palmitic and stearic acids in 0.001 and 0.005 M SDS solution is very similar to those of (propanol + fatty acid) systems. The apparent molar volumes decreased at all concentration of SDS in comparison to corresponding systems without SDS. The results conferred that at molecular arrangements in SDS to (fatty acid+propanol) systems more organized than corresponding systems without SDS. The values of viscosity (η) of laurie, palmitic, and stearic acids in propanol increased with concentration at all six temperatures. The increase of η values of all acids with concentration can be attributed to the increase in both solute—solvent and solute—solute interactions with 17 are found to be increased with the carbon number along the hydrocarbon chain of the fatty acid concentration. At the same time, at a constant temperature and concentration, values of η. can be explained by the increase in both molecular mass of the fatty acid and the degree of solute solvent interactions with carbon number. The ultimate pattern of viscosity after addition of SDS is almost similar to corresponding systems without SDS. The change of free energy, ∆G and enthalpy, ∆H* values for viscous flow were found to be positive work had to be done to overcome the energy barrier for the flow process. The change of entropy, ∆S* values for the flow process are negative in all cases.Item Synthesis and Characterization of Some Biologically Active Copper Complexes for Microbial Applications(Khulna University of Engineering & Technology (KUET), Khulna, Bangladesh., 2015-06) Khan, Mohammed All Azom; Aziz, Prof. Dr. Md. AbdulIn this study, in order to verify our hypothesis amino acid base copper complexes have been prepared for biological application. Reaction of tcydan and Cu(C104)2 6H20 with nucleobases (adenine, hypoxanthine and theophylline) gave three tcydan—metal—amino-acid base complexes, Cu(tcydan)(ade)] .C104.2H20 (1), [{ Cu(tcydan) }2(hypoxanth).(CIO4)3 (2) and H20/CH3 [Cu(tcydan)(theophy)]3.(C104)3.2H20 (3). The complexes were prepared in H CN media at room temperature under pH 8-9. The crystal structures were determined by X-ray diffraction. In the structure of complex 1, the square-pyramidal Cu 2+ ion binds to an adenine ligand through the deprotonated N(9) and to four nitrogens of a tcydan ligand, and an interligand hydrogen bond is formed between the secondary amino nitrogen of tcydan and the ring nitrogen N(3) of the base. In complex 2, two square-pyramidal Cu2 ions bind to a xanthine ligand, one through N(7) with the formation of a hydrogen bond between the exocyclic oxygen 0(6) of the base and the secondary amino nitrogen of a tcydan ligand, and the other through the deprotonated N(9) with the formation of a hydrogen bond between N(3) of the base and the amino nitrogen of tcydan. In the structure of complex 3, the square-pyramidal Cu 2+ ion binds to a theophyllinato ligand through N(7) and four nitrogens of a tcydan ligand with the formation of a hydrogen bond between 0(6) of the base and amino group of tcydan, as observed in 2 and 3. In summary, the adenine complex 1 involves the metal-N(9) bonding with the formation of an N(3) hydrogen bond. On the other hand, the absence of the possible metal bonding to N(7) or N(I) of adenine might be due to a steric repulsion, intramolecular interligand N(tcydan)-H ...between amino groups of tcydan and the N(6) amino group when the metal ion binds to N(7)or N(l) of the base. Synthesized Cu-complexes are quite capable of removing Fecal coliform (FC) from water.