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Studies on Volumetric and Sound Velocity of Ciprofloxacin in Aqueous Solution of Glucose, Sodium Chloride & Potassium Chloride Salts 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, June 2018.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 149-154).In this study, volumetric and sound velocity method was applied to analyze the interaction of
ciprofloxacin on the structure of glucose, NaCl and KCl. Densities and sound velocities of
glucose, NaCl and KCl in water and in aqueous ciprofloxacin (0.03, 0.045 and 0.06) mol.kg-1
solutions have been studied at 293.15 K to 318.15 K with an interval of 5 K temperature. The
density values 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 constant (δ2φv
0/δT2)p. The acoustic properties such as adiabatic
compressibility (βs), apparent molar adiabatic compressibility (φk), 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 also been
calculated by densities and sound velocities data.
The densities increase with the increase of concentration of glucose, NaCl and KCl. Densities
of glucose, NaCl and KCl in aqueous ciprofloxacin solutions are higher than that of glucose,
NaCl and KCl in aqueous solution. The increase of density with concentration of glucose,
NaCl and KCl can be attributed to solute-solvent interaction. The limiting apparent molar
volumes (φv
0) are positive at the studied temperatures for the all mixtures indicate the presence
of solute-solvent interactions. The positive values of Sv indicate strong solute-solute interaction
and φv
0 values suggest the dominance of solute-solvent interaction.
The limiting apparent molar volume transfer (Δtrφv
0) values have been found negative for NaCl
and KCl in (0.03 and 0.045) and (0.03, 0.045 and 0.06) mol.kg-1 aqueous ciprofloxacin
solutions respectively, which suggest the existence of ion-hydrophobic and hydrophobichydrophobic
group interaction. But Δtrφv
0 values are positive for glucose and NaCl in (0.03,
0.045 and 0.06) and 0.06 mol.kg-1 aqueous ciprofloxacin respectively, which suggest the
existence of ion-hydrophilic and hydrophilic-hydrophilic interactions. The values of limiting
apparent molar expansion (Eφ
0) are positive. The Hepler constant (δ2φv
0/δT2)p values are small
negative for all studied glucose, NaCl and KCl suggest the studied systems act as structure
makers. The values of partial molar volumes ( 2) increase with increasing concentration of
glucose, NaCl and KCl for all studied systems.
The sound velocity increases with the increase of concentration of glucose, NaCl and KCl.
Sound velocities of glucose, NaCl and KCl in aqueous ciprofloxacin solutions are higher than
those of glucose, NaCl and KCl in aqueous solution. This indicate that the increase of
compactness of the medium with the increase in glucose, NaCl and KCl and ciprofloxacin
concentration.
The adiabatic compressibility (βs) decreases with the increasing concentration of glucose,
NaCl and KCl. This indicates that water molecules around the glucose, NaCl and KCl are less
compressible than the water molecules in the bulk solution. The negative apparent molar
adiabatic compressibility (φk) 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 mainly positive which
suggest the existence of strong ion-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 domination of solute-solvent interaction over solute-solute interaction.
The acoustic impedance, Z increases with the increase of concentration of glucose, NaCl and
KCl. The relative association, RA decreases linearly with increasing the concentration of solute
indicates the increase of solute-solvent interaction. The positive hydration number (nH) values
indicate an appreciable solvation of solutes.Masuda KhanamMaster of Science in Chemistr
Effect of tri-Potassium citrate on the Structure of Sucrose and Maltose in Solutions at Different Temperatures: Volumetric and Ultrasonic Studies
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, September 2018.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 129-138).A volumetric and sound velocity method was used for the analysis of effect of tri-
Potassium citrate (TPC) on the structure of sucrose and maltose. Densities and sound
velocities of sucrose and maltose in water and in aqueous 0.05 mol.kg-1, 0.20 mol.kg-1,
0.35 mol.kg-1 and 0.5 mol.kg-1 (TPC) solutions have been studied at 293.15K to 313.15K
with an interval of 5K. From density values, various parameters such as 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 have been
calculated. 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) and
hydration number (nH) have been calculated by densities sound velocities data.
The densities increase with the increase of concentration of sucrose and maltose. Densities
of sucrose and maltose in aqueous TPC solutions are higher than that of sucrose and
maltose in pure water solution. The apparent molar volume varies upon the disaccharides
(sucrose and maltose) concentration as well as on the temperature. 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 disaccharides are found to be order of: maltose > sucrose.
The limiting apparent molar volume transfer (Δtrφv
0) values of sucrose and maltose are
positive which suggest the dominance of ion-hydrophilic and hydrophilic-hydrophilic
interactions over the hydrophobic-hydrophobic and ion-hydrophobic interactions. The
Δtrφv
0 values increase with an increase in concentration of the TPC which indicates the
presence of strong ion-hydrophilic interactions in the mixtures. The values of limiting
apparent molar volume expansion (δφv
0/δT)p are positive. Hepler’s constant values are
positive or small negative for all studied disaccharides in binary and ternary system
suggest the studied systems act as structure maker. The values of partial molar volumes
(V2) increase with increasing of concentration of sucrose and maltose for the studied
systems.
The sound velocity increases with the increase of concentration of sucrose and maltose.
Sound velocities of disaccharides in aqueous TPC solutions are higher than that of
disaccharides in pure water solution. This indicate that the increase of compactness of the
medium with the increase in disaccharides and TPC concentration. The adiabatic
compressibility (βs) decreases with the increase of concentration of disaccharides. This
indicates the water molecules around the disaccharides are less compressible than the
water molecules in the bulk solution. The negative k values indicate the greater loss of
structural compressibility of water. The positive Δtrφk
0 values for all the saccharides
indicate the presence of ionic-hydrophilic and hydrophilic-hydrophilic interactions. The
small Sk values also indicates the dominating of solute- solvent interactions over solutesolute
interaction.
The acoustic impedance, Z increases with the increase of concentration of disaccharides
indicates the presence of effective solute-solvent interactions. The hydration number (nH)
decrease with the increase of concentration and temperature for both binary and ternary
systems. The positive hydration number (nH) values indicate an appreciable solvation of
solutes. Hydration capacity of maltose is higher than sucrose in water and in aqueous TPC solution.Subhas Chandra SarkarMaster of Science in Chemistr
Design and Analysis of a Pattern Reconfigurable Antenna for Wi-Fi Base Station
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, November 2018.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 70-73).A unique concept for design of a pattern reconfigurable antenna and its simulation using
CST-MW simulator is presented in this research. The proposed design is a special type of
patch antenna and capable to make coverage at two directions without changing any common
properties of a typical antenna. This antenna is able to reconfigure the beam pattern
automatically, by using a pair of waveguide port without using any type of switching
mechanism. The proposed antenna is able to switch the radiation beam from one direction to
its 1800 reverse angle without changing its operating frequency that is 2.4 GHz. Besides, Wi-
Fi technology is the most popular and widely accepted WLAN (wireless local area network)
that operated at 2.4 GHz. So, this proposed antenna may have been easily adopted by Wi-Fi
(wireless fidelity) technology. This antenna provides wider bandwidth that is 455 MHz. This
enormous bandwidth makes the speed of data flow at higher rate along the WLAN, that’s the
more advantageous for designing a base station. The CST simulator carried out the simulated
result of return loss is -24.5 dB that is acceptable for telecommunication transmitter or
receiver. It covers the region of 480 to 1310 and 2280 to 3120 in azimuth plane. The footprint
of the radiation beam pattern is 820 (3dB points) for both ports. The beam of the antenna
focuses at these directions with directivity of 1.8 dBi. The simulated VSWR (voltage
standing wave ratio) value of antenna is 1.12 for both ports that can be chosen able for
wireless communication technology. It’s compactness in size and fabrication simplicity are
the attracting features for the base station designer. Thus, this proposed antenna can be easily
embedded in Wi-Fi system.Md Nazmul IslamMaster of Science in Engineering in Electronics and Communication Engineerin
Study of the Effect of Rare Earth Ions on the Structural, Magnetic and Electrical Properties of Cu-Zn Ferrites
No full textThis thesis is submitted to the Department of Physics, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Physics, May 2018.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 66-72).Rare earth substituted Fe in Cu-Zn ferrites are well-known technological magnetic materials used for manufacturing of multilayer chip inductor and applications in various electrical devices. The present work is focused on the effect of rare earth ion on structural, magnetic and transport properties of (Cu0.5Zn0.5Fe2-x)RExO4 [ x = 0.00, 0.05 and 0.10] ferrites where RE = La and Sm were prepared by solid state reaction technique keeping in view of their ionic radial and valences for maintain the charge neutrality sintered at 1100oC with 3 hours holding time. The Xray diffraction analysis revealed that rare earth free sample shows formulation of single phase cubic spinel structure with no extra peak but other two La and Sm substituted Fe in Cu-Zn samples show additional peaks other cubic spinel structure and corresponding to a second orthoferrite phase. Lattice parameter, bulk density, Xray density and porosity of the studied samples are increased with both La or Sm substituted ions. Lattice parameter of both series are slightly decrease with increase x content. A significant increase in initial permeability about 620 is found in (Cu0.5Zn0.5Fe1.95)La0.05O4 but increase La content decrease initial permeability. This enhancement of permeability may be correlated with improved microstructural features. But the initial permeability decreases with increasing Sm ions in ferrite. Quality factor signifies the merit of the material from the application point of view. The dielectric constant is found to decrease continuously with increasing frequency and remain almost constant at higher frequency range. The dielectric behavior of the experimental ferrite samples explained on the basis of the mechanism of the dielectric polarization and conduction process. The decrease of saturation magnetization with increasing of both rare earth substitutions has been explained on the Neel’s collinear two sublattices magnetization model and Yafet-Kittels non-collinear magnetization model.Prodip Kumar MondalMaster of Science in Physic