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Studies on Volumetric and Ultrasonic Properties of L-Lysine, L-Ornithine and Glycine in Aqueous Fructose Solution at Different Temperatures
No full textThis thesis is submitted to the Department of Chemistry, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Chemistry, March 2018.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 196-205)In this study, the interaction of amino acids (glycine, L-ornithine and L-lysine) in water
and aqueous fructose solution has been determined by using volumetric and sound velocity
method. Interactions of glycine, L-ornithine and L-lysine in aqueous fructose solution play
an important role to understand biochemical process in living cells. Densities and sound
velocities of glycine, L-ornithine and L-lysine in water and in aqueous 0.05 mol.kg-1,
0.20 mol.kg-1, 0.35 mol.kg-1 and 0.50 mol.kg-1 fructose solutions have been studied at
293.15K to 318.15K with an interval of 5K. The density data have been used to calculate
apparent molar volume (φv), limiting apparent molar volume (φv
0), limiting apparent molar
volume transfer (Δtrφv
0), apparent molar expansibilities (δφv
0/δT)p and Hepler’s constant
(δ2φv
0/δT2)p. The acoustic properties such as adiabatic compressibility (βs), apparent molar
adiabatic compressibility (k), limiting apparent molar adiabatic compressibility (φk
0),
apparent molar adiabatic compressibility of transfer (Δtrφk
0), acoustic impedance (Z),
relative association (RA) and hydration number (nH) have been calculated by densities and
sound velocities data.
The densities increase with the increase of concentration of amino acids (glycine,
L-ornithine and L-lysine). Densities of glycine, L-ornithine and L-lysine in aqueous
fructose solutions are higher than that of glycine, L-ornithine and L-lysine in aqueous
solution. The smaller values of experimental slope (Sv) as compared to limiting apparent
molar volume (φv
0) values suggest the dominance of solute-solvent interaction over the
solute-solute interaction. The true volume (φv
0) of amino acids are found to be order of
L-lysine > L-ornithine > glycine.
The limiting apparent molar volume transfer (Δtrφv
0) values of glycine, L-ornithine and
L-lysine are positive which suggest the dominance of ion-hydrophilic and hydrophilichydrophilic
interactions over the hydrophobic-hydrophobic and ion-hydrophobic
interaction. The values of limiting apparent molar expansion (δφv
0/δT)p are positive.
Hepler’s constant (δ2φv
0/δT2)p values are small negative for all studied amino acids in
binary and ternary system suggest the studied systems act as structure maker. The values
of partial molar volumes ( 2) increase with increasing of concentration of glycine, L-ornithine and L-lysine for the studied systems. This trend of 2 indicates solute-solvent
interactions increase with increasing concentration of amino acids.
The sound velocity increases with the increase of concentration of L-lysine, L-ornithine
and glycine. This may be attributed to the increase of compactness of the medium with the
increase in amino acids concentration. Sound velocities of L-lysine, L-ornithine and
glycine in aqueous fructose solutions are higher than that of L-lysine, L-ornithine and
glycine in aqueous solution. The adiabatic compressibility (βs) decreases with the increase
of concentration of L-lysine, L-ornithine and glycine. This indicates the water molecules
around the amino acids are less compressible than the water molecules in the bulk solution.
The negative apparent molar adiabatic compressibility (k) values indicate the greater loss
of structural compressibility of water. The values of limiting apparent molar adiabatic
compressibility (φk
0) are negative. The values of apparent molar adiabatic compressibility
transfer (Δtrφk
0) are positive which suggest the existence of strong solute-solvent
interaction. At lower concentration, negative values of Δtrφk
0 indicate that increase in
hydrophobic-hydrophobic group interactions. The small Sk values also indicates the
dominating of solute-solvent interactions over solute-solute interaction. The acoustic
impedance, Z increases with the increase of concentration of amino acids. The relative
association, RA decreases linearly with increasing the concentration of solute. The positive
hydration number (nH) values indicate an appreciable solvation of solutes.
Therefore, the water molecules around amino acids are less compressible than water
molecules in the bulk solution. The compressibility of ternary solution is lower than binary
solution. This result suggests that the proteins or peptides generated from the studied
amino acids will be denatured in ternary fructose solution.Md. TariquzzamanMaster of Science in Chemistr
Cross-correlation based Acoustic Signal Processing Technique and its Implementation on Marine Ecology
No full textThis thesis is submitted to the Department of Electronics and Communication Engineering, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in Electronics and Communication Engineering, December 2018.Cataloged from PDF Version of Thesis.Includes bibliographical references in each chapter.As a scientific study of marine-life habitation, populations, and interactions among organisms and surrounding environment, marine ecology includes numerous fish and mammals as part and parcel. Marine fish and mammals have an enormous impact on marine ecosystems. Not only for their ecological values, but also for commercial purposes, a proper estimation of their population size is necessary. Besides, an efficient monitoring of populations and communities is the precondition of ecosystem-based management in marine areas. Most conventional techniques for estimating fish population are visual sampling techniques, environmental DNA (eDNA) technique, minnow traps, removal method of population estimation, echo integration techniques, etc., which are sometimes complex, costly, require human interaction, and harmful for inhabitation of marine species. In order to overcome these difficulties, an acoustic signal processing technique is proposed in this thesis. The method is based on a novel statistical signal processing technique called “cross-correlation” and different types of acoustic signals produced by diverse species of marine fish and mammals, like chirps, grunts, growls, clicks, etc. Our goal was to build a framework so that the technique can be implemented in practice. Therefore, we have investigated different tasks, which are crucial during its practical implementation like estimation with respect to different fish acoustics, different number of sensors and different distributions of fish and mammals. Similarly, we have carried an investigation to select the optimum estimation parameter for the technique. We have also analyzed different impacts, i.e., underwater bandwidth, SNR, etc., which have significant effects on practical estimation of this technique. From this research, we have found that chirp signals can produce better estimation results among the three fish acoustics, i.e., chirps, grunts, and growls signals. Among the three fish distributions, i.e., Exponential, Normal, and Rayleigh, Exponential distribution of fish and mammals produce better results. An increasing number of acoustic sensors provide better results in this technique. However, limited bandwidth of underwater channel poses a barrier during acquisition of fish signals, which has infinite bandwidth. To overcome this problem, a proper scaling is a mandatory task. We find that scaling factor 0.59512 for chirp signal and 0.55245 for grunt signal at 5 kHz underwater bandwidth. Similarly, a low signal to noise ratio (SNR) is also an impediment to obtain an accurate fish population. We have found that estimation with minimum SNR of 20 can perform like the noiseless estimation. These findings will immensely help the future researchers during practical implementation of the technique.S. M. Asif HossainMaster of Science in Engineering in Electronics and Communication Engineerin
Volumetric and Viscometric Study of Dimedone in Ethanol-Water Mixtures
No full textThis thesis is submitted to the Department of Chemistry, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Chemistry, October, 2017.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 86-89)Density and viscosity of binary (Dimedone-Ethanol) and ternary (Dimedone-Ethanol –
Water) mixtures of Dimedone, Water and Ethanol were determined at various
temperatures (298.15 to 318.15 K at 5 K intervals) in between a concentration range of
0.05 to 0.25 mol L-1 of Dimedone with a view to determining the molecular interactions
among Dimedone, Water and Ethanol. Dimedone is an organic substance which has the applications in colorimetry, crystallography, luminescence and spectrophotometric
analysis. And it can also be used for chemistry involving organic compounds of low
electrical resistance. Ethanol is a colourless organic polar solvent has led to its largescale production in recent years with negligible toxicity. Ethanol is completely miscible with universal solvent water. So Ethanol– Water mixture can be a vital binary solution in investigating Dimedone that was taken as topic of research in this study. The
apparent molar volumes, (φ ) were obtained from the experimental density data. In the
Dimedone–Ethanol and Dimedone–Water–Ethanol system, the apparent molar volume
of Dimedone increases. In addition, apparent molar volume at infinite dilution (φ ),
apparent molar Expansivity and Sv (values of experimental slopes) were also calculated
according to the experimental density data. The apparent molar volume at infinite
dilution gives an idea about the presence of solutesolvent interactions whereas Sv is
the experimental slopes which give an idea about the prevailing solutesolute
interactions in the mixtures. The calculated data indicate that there may be solute-solute
and solute-solvent interactions present in the binary and ternary solutions. It is seen that
Dimedone has good structure making property in ternary solutions than the binary
systems. Both binary and ternary systems shows rapid increase of viscosity values with
the increased Dimedone concentration but the values of viscosity decreased with the
increase of temperature. The viscosity data were employed to determine the viscosity
coefficients (A&B), change of free energy, G*, change of enthalpy, H* as well as
change of entropy, S*. From these thermodynamic parameters state of the spontaneity
of the investigated systems were known. Moreover, positive A co-efficients and
negative B co-efficients suggesting that strong solute-solute but weak solute-solvent
interaction present in the binary and ternary solution. On the basis of this data, the
predominant molecular interactions occurring between Dimedone-Ethanol and
Dimedone–Water–Ethanol were found to be solute-solute interaction. The results
suggest that there is a significant effect of Dimedone on Water and Ethanol.Md. Jahangir HossainMaster of Science in Chemistr
