Ameena parveen - Academia.edu (original) (raw)
Papers by Ameena parveen
Mechanical Engineering Advances, Dec 14, 2023
Journal of Advanced Physics, Sep 1, 2014
Journal of Advanced Physics, 2014
Bulletin of Materials Science, 2006
Engineering science & technology, Aug 20, 2023
We designed and analyzed a magnetic field sensor with low bend losses 2D photonic crystal fiber b... more We designed and analyzed a magnetic field sensor with low bend losses 2D photonic crystal fiber based on a rhombic ring resonator. The proposed design consists of silicon rods with a diameter of 200 nm in the X and Z directions, which are 61 × 61 silicon rods. The Refractive Index (RI) of silicon is n = 3.48 at λ = 1.55 mm and the number of air holes along the direction is 33 × 33. It was found that the photonic crystal fibers used the photonic band gap phenomenon to guide light but rather an area of the fiber core with a lower refractive index of 0.9 nm. It is important to note that there are low bend losses in 2D photonic crystal fibers, enabling response to small changes in the magnetic fluid viscosity, refractive index, and other physical parameters. The flow of electromagnetic energy, indicated by the Poynting vector (s), indicates that the magnitude of the power carrier per unit area in the direction of S is approximately 1.23 W/m 2 .
Polymers for Advanced Technologies, 2016
Journal of Materials Science: Materials in Electronics
Journal of Materials Science: Materials in Electronics
Journal of Electronic Materials, 2019
Nanotubes of nickel ferrite were prepared by the citrate method and were used in nanocomposite sy... more Nanotubes of nickel ferrite were prepared by the citrate method and were used in nanocomposite synthesis via in situ polymerization technique. The structural and surface morphology characterizations were carried out by Fouriertransform infrared spectroscopy (FTIR), x-ray powder diffraction (XRD), and scanning electron microscopy (SEM) techniques. FTIR spectra show the characteristic peaks of benzenoid ring, quinoid ring, and nickel ferrite stretching of tetrahedral and octahedral sites. XRD pattern shows the cubic spinal structure of NiFe 2 O 4 nanotubes and it remaining undistorted even after dispersion in a polyaniline matrix. The SEM image of 15 wt.% nanocomposite shows that the polyaniline coated nickel ferrite nanotubes form a length about 100 nm. Furthermore, the DC conductivity shows three steps conductivity feature and among all prepared nanocomposites, the 15 wt.% shows high conductivity of 1.89 S/cm. This is due to high absorption at activation energy of 0.213 9 10 À2 J/mol and elongation of nanocomposites chain length which is confirmed from the negative thermal coefficient (NTC) graph. The vibrating sample magnetometer (VSM) study shows the saturation magnetization decrease after formation of polyaniline nanocomposite. The dielectric properties were analyzed by impedance analyzer, and it was found that 15 wt.% nanocomposite shows the lowest dielectric constant and dielectric loss as a result of high ac conductivity of about 1.32 S/cm which is due to the sharp drop in bulk resistance and low relaxation time of 0.1375 ls as evidenced from the cole-cole plot.
Polymers for Advanced Technologies, 2016
Polyaniline-Nd 2 O 3 :Al 2 O 3 nanocomposites were prepared by in situ oxidative polymerization m... more Polyaniline-Nd 2 O 3 :Al 2 O 3 nanocomposites were prepared by in situ oxidative polymerization method using different weight percentages of oxide powders. The prepared nanocomposites were characterized by Fourier transform infrared spectroscopy and X-ray diffraction for molecular and crystal structures. Scanning electron microscopy and transmission electron microscopy images show the tubular structure of polyaniline nanocomposite with embedded metal oxides. The electrical conductivity of the nanocomposites increases with increase in temperature as well as with concentration of Nd 2 O 3 :Al 2 O 3 particles in polyaniline. This is because of the hopping of charge polarons and extended chain length of the nanocomposites as evidenced by the negative thermal coefficient (NTC) characteristic. A high NTC value of 2.67 was found in nanocomposites with 15 wt% of oxide particles. These nanocomposites show low dielectric constant and dielectric loss; the electrical conductivity is higher than 0.3 S/cm as confirmed by Cole-Cole plot that indicates a decrease in both grain resistance and bulk resistance of the nanocomposites. The current-voltage and capacitance-voltage measurements were also carried out. The carrier mobility μ values of pure polyaniline and nanocomposites were found to be 4.27 × 10 À3 and 1.45 × 10-2 H.M À1 , respectively. A significant enhancement in carrier mobility was observed in comparison with the literature.
Journal of Materials Research, 2015
A facile synthesis method was adapted to prepare Ortho-chloropolyaniline/graphite oxide (OPANI/GO... more A facile synthesis method was adapted to prepare Ortho-chloropolyaniline/graphite oxide (OPANI/GO) composites. The properties of these composites have been discussed based on different characterizations such as scanning electron microscopy, FTIR, and dielectric studies. The important peaks of benzenoid and quinoid rings in the spectrum confirm the formation of composites. Scanning electron microscopic studies indicate that the morphology of the prepared composites was influenced by different weight ratios of GO in OPANI and the resulting micrographs of these composites exhibited flaky and folded structures. The electrical conductivity study was carried out and found that 6 wt% of GO in PANI shows high conductivity value of 20 Â 10 À2 S/cm. The obtained results suggest an easy approach to prepare such novel nanocomposites with excellent dielectric properties which can be used in many technological applications.
Journal of Advanced Physics, 2013
ABSTRACT Poly(ethylene oxide)–Mg(ClO3�2 composites have been prepared by slurry method using acet... more ABSTRACT Poly(ethylene oxide)–Mg(ClO3�2 composites have been prepared by slurry method using acetonitrile as an solvent with different weight percentage. The prepared composites were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. FTIR study shows the characteristic vibrational bands of the PEO and dopant metal chlorate, confirms the formation polymer composites. SEM image revels that the composites are highly agglomerated and irregular in shape. The dielectric studies were carried out in a frequency range from 102–106 Hz. From dielectric studies it is observed that the permittivity and dielectric loss value decreases with increase in frequency. Electrochemical cells parameters shows that 25 wt% of PEOMg(ClO3�2 composite has high charge density, open circuit voltage and polarization current with respective to the charging time.
Sensor Review, 2012
Purpose–The purpose of this paper is to study the sensitivity and selectivity properties of polya... more Purpose–The purpose of this paper is to study the sensitivity and selectivity properties of polyaniline/tantalum pentoxide (PANI/Ta 2 O 5) composite to liquid petroleum gas (LPG). Design/methodology/approach–Polyaniline/tantalum pentaoxide (PANI/Ta 2 O 5) ...
Journal of Magnetism and Magnetic Materials, 2013
Nanoparticles of Cu-Cd-Ni-FeO 4 were synthesized by the auto-combustion process using a modified ... more Nanoparticles of Cu-Cd-Ni-FeO 4 were synthesized by the auto-combustion process using a modified citric acid method. Antibacterial activity, structural, dielectric and magnetic properties were investigated. An assay showed the broad spectrum antibacterial activity of Cu-Cd-Ni-FeO 4 against Gram positive and Gram negative pathogenic bacterial strains. The existence of single phase cubic spinel structure of ferrites was confirmed by X-ray diffraction measurement. Fourier transform infrared spectroscopy shows the two main absorption bands at lower frequency region. Surface morphology and compositional features were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy analysis, respectively. Results indicated that the nanosize particles greatly influenced the antibacterial activity, as well as structural, dielectric and magnetic properties of the samples. Magnetic measurements of the samples were carried out by means of vibrating sample magnetometry and Mössbauer spectroscopy. Magnetic properties are strongly affected by Ni 2+ substitution.
Composites Part B: Engineering, 2013
ABSTRACT Polyethylene oxide - NaClO3 composite have been prepared by solution casting technique w... more ABSTRACT Polyethylene oxide - NaClO3 composite have been prepared by solution casting technique with different weight percentages as a polymer electrolyte for battery application. The prepared composites were characterized by various tools like XRD, FTIR and SEM. The X-ray diffraction analysis shows the complexation of polymer with salt and existence of both crystalline and amorphous phases. From FTIR spectra confirms the formation of PEO -NaClO3 composites. SEM images shows the grains are highly agglomerated and its average size increases with increase in salt ratio. Frequency dependence of dielectric property and ac electrical conductivity of polymer electrolytes were studied within the frequency range of 50Hz to 5MHz using complex impedance analysis technique. Ionic conductivity follows Arrhenius type behavior as a function of temperature. The fabricated cell of 25 wt% of PEO- NaClO3 composites generated high current of 1.79 A.
Composites Part B: Engineering, 2013
In this study, the dielectric properties of PVA/ZnO nanocomposites films were evaluated. The comp... more In this study, the dielectric properties of PVA/ZnO nanocomposites films were evaluated. The composites were prepared by a solution casting technique. The dispersion and functionalization of the ZnO nanoparticles in the composite films were characterized by spectroscopic technique. The surface morphology of the PVA/ZnO nanocomposites films were elucidated using AFM. The charge transport properties were evaluated based on the dielectric and impedance spectroscopy techniques. Low ZnO loading composite shows low dielectric value at higher frequency and behaves as a lossless material. The complex impedance spectra suggest the change in conductivity, due to the change in bulk resistance of the materials and less relaxation time. Thus, all PVA/ZnO nanocomposites behave as lossless materials above 10 6 Hz indicating the composites are useful in microwave application.
IEEE Sensors Journal, 2012
ABSTRACT Polyaniline - CaTiO3 nanocomposites with their various weight percentages prepared by ch... more ABSTRACT Polyaniline - CaTiO3 nanocomposites with their various weight percentages prepared by chemical oxidative in situ polymerization technique. The prepared composites were characterized by FTIR, SEM and XRD. The temperature-dependent DC conductivity of Polyaniline /CaTiO3 nanocomposite was studied within the range of 40-200ﾟC and found that 50 wt% shows high conductivity compared to other composites. Humidity sensor properties of Polyaniline /CaTiO3 nanocomposite shows better sensing properties and exhibits good linearity in sensing response curve which discuss the implications of distortions and non-stoichiometry on their physical properties. Among all composites, 50 wt% of polyaniline – CaTiO3 nanocomposites shows high sensitivity up to ̴ 90% and its response – recovery times are 500Sec and 453Sec respectively.
The different investigation has been carried out on the biological activities of titanium dioxide... more The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory c...
The filtering process is widely used in several digital signal processing and digital image proce... more The filtering process is widely used in several digital signal processing and digital image processing applications. The filter process is to remove the noise in original signal or image. THE LEAST MEAN SQUARE (LMS) adaptive filter is the most popular and most widely used adaptive filter because of its simplicity and also for satisfactory convergence performance. But conventional LMS adaptive filter involves a long critical path due to an inner-product computation to obtain the filter output. That critical path is required to be reduced by pipelined implementation called delayed LMS (DLMS) adaptive filter. The conventional delayed LMS adaptive filter architecture occupies more area, more power wastage and less performance then compare with this proposed architecture. From the critical path evaluation, it is shown that no pipelining is required for implementing a direct form LMS adaptive filter for most practical cases, and can be realized with a very small adaptation delay in cases ...
Mechanical Engineering Advances, Dec 14, 2023
Journal of Advanced Physics, Sep 1, 2014
Journal of Advanced Physics, 2014
Bulletin of Materials Science, 2006
Engineering science & technology, Aug 20, 2023
We designed and analyzed a magnetic field sensor with low bend losses 2D photonic crystal fiber b... more We designed and analyzed a magnetic field sensor with low bend losses 2D photonic crystal fiber based on a rhombic ring resonator. The proposed design consists of silicon rods with a diameter of 200 nm in the X and Z directions, which are 61 × 61 silicon rods. The Refractive Index (RI) of silicon is n = 3.48 at λ = 1.55 mm and the number of air holes along the direction is 33 × 33. It was found that the photonic crystal fibers used the photonic band gap phenomenon to guide light but rather an area of the fiber core with a lower refractive index of 0.9 nm. It is important to note that there are low bend losses in 2D photonic crystal fibers, enabling response to small changes in the magnetic fluid viscosity, refractive index, and other physical parameters. The flow of electromagnetic energy, indicated by the Poynting vector (s), indicates that the magnitude of the power carrier per unit area in the direction of S is approximately 1.23 W/m 2 .
Polymers for Advanced Technologies, 2016
Journal of Materials Science: Materials in Electronics
Journal of Materials Science: Materials in Electronics
Journal of Electronic Materials, 2019
Nanotubes of nickel ferrite were prepared by the citrate method and were used in nanocomposite sy... more Nanotubes of nickel ferrite were prepared by the citrate method and were used in nanocomposite synthesis via in situ polymerization technique. The structural and surface morphology characterizations were carried out by Fouriertransform infrared spectroscopy (FTIR), x-ray powder diffraction (XRD), and scanning electron microscopy (SEM) techniques. FTIR spectra show the characteristic peaks of benzenoid ring, quinoid ring, and nickel ferrite stretching of tetrahedral and octahedral sites. XRD pattern shows the cubic spinal structure of NiFe 2 O 4 nanotubes and it remaining undistorted even after dispersion in a polyaniline matrix. The SEM image of 15 wt.% nanocomposite shows that the polyaniline coated nickel ferrite nanotubes form a length about 100 nm. Furthermore, the DC conductivity shows three steps conductivity feature and among all prepared nanocomposites, the 15 wt.% shows high conductivity of 1.89 S/cm. This is due to high absorption at activation energy of 0.213 9 10 À2 J/mol and elongation of nanocomposites chain length which is confirmed from the negative thermal coefficient (NTC) graph. The vibrating sample magnetometer (VSM) study shows the saturation magnetization decrease after formation of polyaniline nanocomposite. The dielectric properties were analyzed by impedance analyzer, and it was found that 15 wt.% nanocomposite shows the lowest dielectric constant and dielectric loss as a result of high ac conductivity of about 1.32 S/cm which is due to the sharp drop in bulk resistance and low relaxation time of 0.1375 ls as evidenced from the cole-cole plot.
Polymers for Advanced Technologies, 2016
Polyaniline-Nd 2 O 3 :Al 2 O 3 nanocomposites were prepared by in situ oxidative polymerization m... more Polyaniline-Nd 2 O 3 :Al 2 O 3 nanocomposites were prepared by in situ oxidative polymerization method using different weight percentages of oxide powders. The prepared nanocomposites were characterized by Fourier transform infrared spectroscopy and X-ray diffraction for molecular and crystal structures. Scanning electron microscopy and transmission electron microscopy images show the tubular structure of polyaniline nanocomposite with embedded metal oxides. The electrical conductivity of the nanocomposites increases with increase in temperature as well as with concentration of Nd 2 O 3 :Al 2 O 3 particles in polyaniline. This is because of the hopping of charge polarons and extended chain length of the nanocomposites as evidenced by the negative thermal coefficient (NTC) characteristic. A high NTC value of 2.67 was found in nanocomposites with 15 wt% of oxide particles. These nanocomposites show low dielectric constant and dielectric loss; the electrical conductivity is higher than 0.3 S/cm as confirmed by Cole-Cole plot that indicates a decrease in both grain resistance and bulk resistance of the nanocomposites. The current-voltage and capacitance-voltage measurements were also carried out. The carrier mobility μ values of pure polyaniline and nanocomposites were found to be 4.27 × 10 À3 and 1.45 × 10-2 H.M À1 , respectively. A significant enhancement in carrier mobility was observed in comparison with the literature.
Journal of Materials Research, 2015
A facile synthesis method was adapted to prepare Ortho-chloropolyaniline/graphite oxide (OPANI/GO... more A facile synthesis method was adapted to prepare Ortho-chloropolyaniline/graphite oxide (OPANI/GO) composites. The properties of these composites have been discussed based on different characterizations such as scanning electron microscopy, FTIR, and dielectric studies. The important peaks of benzenoid and quinoid rings in the spectrum confirm the formation of composites. Scanning electron microscopic studies indicate that the morphology of the prepared composites was influenced by different weight ratios of GO in OPANI and the resulting micrographs of these composites exhibited flaky and folded structures. The electrical conductivity study was carried out and found that 6 wt% of GO in PANI shows high conductivity value of 20 Â 10 À2 S/cm. The obtained results suggest an easy approach to prepare such novel nanocomposites with excellent dielectric properties which can be used in many technological applications.
Journal of Advanced Physics, 2013
ABSTRACT Poly(ethylene oxide)–Mg(ClO3�2 composites have been prepared by slurry method using acet... more ABSTRACT Poly(ethylene oxide)–Mg(ClO3�2 composites have been prepared by slurry method using acetonitrile as an solvent with different weight percentage. The prepared composites were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. FTIR study shows the characteristic vibrational bands of the PEO and dopant metal chlorate, confirms the formation polymer composites. SEM image revels that the composites are highly agglomerated and irregular in shape. The dielectric studies were carried out in a frequency range from 102–106 Hz. From dielectric studies it is observed that the permittivity and dielectric loss value decreases with increase in frequency. Electrochemical cells parameters shows that 25 wt% of PEOMg(ClO3�2 composite has high charge density, open circuit voltage and polarization current with respective to the charging time.
Sensor Review, 2012
Purpose–The purpose of this paper is to study the sensitivity and selectivity properties of polya... more Purpose–The purpose of this paper is to study the sensitivity and selectivity properties of polyaniline/tantalum pentoxide (PANI/Ta 2 O 5) composite to liquid petroleum gas (LPG). Design/methodology/approach–Polyaniline/tantalum pentaoxide (PANI/Ta 2 O 5) ...
Journal of Magnetism and Magnetic Materials, 2013
Nanoparticles of Cu-Cd-Ni-FeO 4 were synthesized by the auto-combustion process using a modified ... more Nanoparticles of Cu-Cd-Ni-FeO 4 were synthesized by the auto-combustion process using a modified citric acid method. Antibacterial activity, structural, dielectric and magnetic properties were investigated. An assay showed the broad spectrum antibacterial activity of Cu-Cd-Ni-FeO 4 against Gram positive and Gram negative pathogenic bacterial strains. The existence of single phase cubic spinel structure of ferrites was confirmed by X-ray diffraction measurement. Fourier transform infrared spectroscopy shows the two main absorption bands at lower frequency region. Surface morphology and compositional features were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy analysis, respectively. Results indicated that the nanosize particles greatly influenced the antibacterial activity, as well as structural, dielectric and magnetic properties of the samples. Magnetic measurements of the samples were carried out by means of vibrating sample magnetometry and Mössbauer spectroscopy. Magnetic properties are strongly affected by Ni 2+ substitution.
Composites Part B: Engineering, 2013
ABSTRACT Polyethylene oxide - NaClO3 composite have been prepared by solution casting technique w... more ABSTRACT Polyethylene oxide - NaClO3 composite have been prepared by solution casting technique with different weight percentages as a polymer electrolyte for battery application. The prepared composites were characterized by various tools like XRD, FTIR and SEM. The X-ray diffraction analysis shows the complexation of polymer with salt and existence of both crystalline and amorphous phases. From FTIR spectra confirms the formation of PEO -NaClO3 composites. SEM images shows the grains are highly agglomerated and its average size increases with increase in salt ratio. Frequency dependence of dielectric property and ac electrical conductivity of polymer electrolytes were studied within the frequency range of 50Hz to 5MHz using complex impedance analysis technique. Ionic conductivity follows Arrhenius type behavior as a function of temperature. The fabricated cell of 25 wt% of PEO- NaClO3 composites generated high current of 1.79 A.
Composites Part B: Engineering, 2013
In this study, the dielectric properties of PVA/ZnO nanocomposites films were evaluated. The comp... more In this study, the dielectric properties of PVA/ZnO nanocomposites films were evaluated. The composites were prepared by a solution casting technique. The dispersion and functionalization of the ZnO nanoparticles in the composite films were characterized by spectroscopic technique. The surface morphology of the PVA/ZnO nanocomposites films were elucidated using AFM. The charge transport properties were evaluated based on the dielectric and impedance spectroscopy techniques. Low ZnO loading composite shows low dielectric value at higher frequency and behaves as a lossless material. The complex impedance spectra suggest the change in conductivity, due to the change in bulk resistance of the materials and less relaxation time. Thus, all PVA/ZnO nanocomposites behave as lossless materials above 10 6 Hz indicating the composites are useful in microwave application.
IEEE Sensors Journal, 2012
ABSTRACT Polyaniline - CaTiO3 nanocomposites with their various weight percentages prepared by ch... more ABSTRACT Polyaniline - CaTiO3 nanocomposites with their various weight percentages prepared by chemical oxidative in situ polymerization technique. The prepared composites were characterized by FTIR, SEM and XRD. The temperature-dependent DC conductivity of Polyaniline /CaTiO3 nanocomposite was studied within the range of 40-200ﾟC and found that 50 wt% shows high conductivity compared to other composites. Humidity sensor properties of Polyaniline /CaTiO3 nanocomposite shows better sensing properties and exhibits good linearity in sensing response curve which discuss the implications of distortions and non-stoichiometry on their physical properties. Among all composites, 50 wt% of polyaniline – CaTiO3 nanocomposites shows high sensitivity up to ̴ 90% and its response – recovery times are 500Sec and 453Sec respectively.
The different investigation has been carried out on the biological activities of titanium dioxide... more The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory c...
The filtering process is widely used in several digital signal processing and digital image proce... more The filtering process is widely used in several digital signal processing and digital image processing applications. The filter process is to remove the noise in original signal or image. THE LEAST MEAN SQUARE (LMS) adaptive filter is the most popular and most widely used adaptive filter because of its simplicity and also for satisfactory convergence performance. But conventional LMS adaptive filter involves a long critical path due to an inner-product computation to obtain the filter output. That critical path is required to be reduced by pipelined implementation called delayed LMS (DLMS) adaptive filter. The conventional delayed LMS adaptive filter architecture occupies more area, more power wastage and less performance then compare with this proposed architecture. From the critical path evaluation, it is shown that no pipelining is required for implementing a direct form LMS adaptive filter for most practical cases, and can be realized with a very small adaptation delay in cases ...