SHAISTA AFRIDI - Academia.edu (original) (raw)

Papers by SHAISTA AFRIDI

Journal of the Pakistan Institute of Chemical Engineers, Mar 6, 2023

Relative humidity is the prime parameter in industrial processes, which are measured through the ... more Relative humidity is the prime parameter in industrial processes, which are measured through the ceramic, metal oxide and polymeric sensors. Ceramic and metal oxide sensors show nonlinear resistive behaviours with increasing relative humidity and high sintering temperature for hydro-desorption. The transformation of ceramic and metallic sensors with polymeric sensors is due to its eco-friendly synthesis fabrication, less heatintensive and high sensitivity. In this research work, a polymeric sensor of enhanced electric properties with sustainable captive and resistive response was synthesised from nano-fibres graphene oxide for sensing humidity. The synthesized graphene oxide through the modified Hammer method was mixed with poly-vinyl alcohol (GO/PVA) in the ratio of 5 wt % for four hours at 90 ºC. Nano fibres of graphene oxide and poly-vinyl alcohol (GO/PVA) solutions were obtained at the 24V DC electric field; 0.5 ml/h feed rate and 10 cm tip-tocollector distance through electrospinning. GO/PVA fibres were deposited on the silver inter-digited electrodes of 8mm and five combs of 20ìm consecutive distance. SEM analysis shows that the fibres were in the nano-range with no major cracks while XRD and FTIR spectrum investigated the fingerprints and functional groups of GO and GO/PVA respectively. The parametric study of resistive and capacitive was analysed at different response and recovery times at various frequencies in the range of 0 % to 82% relative humidity.

Journal of Porous Materials

The original article has been corrected. Publisher's Note Springer Nature remains neutral with re... more The original article has been corrected. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Separation Science and Technology

Journal of Porous Materials

Journal of the Pakistan Institute of Chemical Engineers

In this work, nickel was deposited on copper substrate through electrodeposition which was abstra... more In this work, nickel was deposited on copper substrate through electrodeposition which was abstracted from local sulphate salt. Nickel deposition on copper substrate was done in both presence of vitamin C and saccharin additive. Boric oxide was used as buffering agent and pH of the solution bath was maintained through sulfuric acid and ammonium hydroxide. Round shape deposition on copper substrate was observed in the presence of vitamin C, while columnar shape particles were observed in the presence of saccharin additive. Deposition of nickel was done through sulfate bath on copper substrate. Boric acid was used as buffering agent and direct current electrolysis were conduct throughout this experimental work. pH of the solution was kept constant with the help of diluted sulfuric acid and ammonium hydroxide. The deposited nickel particles were obtained in round shape in the presence of vitamin additive, while columnar shape particles obtained in saccharin additive. The experimental c...

Journal of the Pakistan Institute of Chemical Engineers, Oct 13, 2021

Journal of the Pakistan Institute of Chemical Engineers, Oct 7, 2021

SSRN Electronic Journal, 2022

Materials Research Express, 2021

Quest for alternate energy sources is the core of most of the research activities these days. No ... more Quest for alternate energy sources is the core of most of the research activities these days. No matter how small or large amount of energy can be produced by utilizing the non-conventional techniques and sources, every bit of innovation can reshape the future of energy. In this work, experimental analysis of the thermoelectric (TE) properties of bulk-graphene in the temperature range of (303 to 363) K is presented. Graphene powder was pressed to form a pellet which was used to fabricate the TE device. The effects of temperature on the Seebeck coefficient, electrical and thermal conductivities, and the dimensionless figure of merit (FOM) were measured. The increasing value of the Seebeck coefficient (thermopower) with temperature is indicant of the metallic behavior. Additionally, the observed thermopower (TEP) is positive, which shows that the majority charge carriers are holes and peaked to a value of 56 μV K−1 at 363 K. The thermopower of the pellet is four times larger than the ...

Materials Research Express, 2021

Ceramic membranes are considered superior over their polymeric counterparts for applications at h... more Ceramic membranes are considered superior over their polymeric counterparts for applications at high temperature, pressure, and in aggressive environments with additional advantages of cleaning at high temperature. Preparation of porous ceramic membrane is expensive because the ceramic materials cannot be processed in a liquid state as polymers. Ceramic membrane synthesis involved solid powder preparation, consolidation, suspension formation, calcination, and sintering temperature which makes its synthesis very expensive. Geopolymerization is a heterogeneous reaction of aluminosilicate materials and chemical activators to form a three-dimensional structure having high mechanical strength without sintering. The overall percent energy and cost-saving of geopolymeric membranes were compared with conventional ceramic membranes. Recently, the geopolymerization technique has been used for membrane synthesis to replace conventional ceramic membrane synthesis. The objective of this review a...

Materials Research Express, 2021

Recently, metal halide perovskite materials for solar cells have gained a wonderful attention fro... more Recently, metal halide perovskite materials for solar cells have gained a wonderful attention from researchers around the world. In this paper, a novel perovskite layer in combination with other layers is numerically investigated to enhance the performance of perovskite-based solar cells (PSCs). General-purpose photovoltaic device model (GPVDM) is used to simulate the proposed structure with Methylammonium Lead Iodide (CH3NH3PbI3), sandwiched between a bi- and tri-layer. The results show enhanced short circuit current density (J sc ) and power conversion efficiency (PCE) for PSCs. The proposed PSCs show a Jsc of 39.6 mA cm−2 and PCE 31.4% under standard AM 1.5 G. The bi- and tri-layer sandwiched CH3NH3PbI3 structure is an elegant solution for the realization of high efficiency PSCs.

Materials, 2019

Liquid exfoliated molybdenum disulfide (MoS2) nanosheets and polyaniline (PANI) nanoparticles are... more Liquid exfoliated molybdenum disulfide (MoS2) nanosheets and polyaniline (PANI) nanoparticles are dispersed in polystyrene (PS) matrix to fabricate hybrid polymer composites with high dielectric and electromagnetic interference (EMI) shielding behavior. A phase-separated morphology is formed when PANI and MoS2 are incorporated into polystyrene (PS) matrix. An increasing concentration of MoS2 nanoparticles inside PS/PANI (5 wt %) polymer blend forms an interconnected network, resulting in high electrical conductivity and dielectric behavior, making them a suitable candidate for EMI shielding application. An increment in dielectric constant and loss, up to four and five orders of magnitude, respectively, is recorded at a maximum concentration of 1 wt % of MoS2 in PS/PANI-5 polymer blend at 100 Hz. The enhanced dielectric characteristics for PS/PANI/MoS2 composites are then theoretically evaluated for the estimation of EMI shielding effectiveness in the frequency range of 100 Hz to 5 M...

Several studies have been conducted on radiation effects on organisms. Although most of the inter... more Several studies have been conducted on radiation effects on organisms. Although most of the interest has been on humans, yet during the last few years increasing attention has been directed to other organisms, focusing on an ecosystem perspective with the intention of defining safe levels of radiation. In this study, we looked at low dose effects of gamma radiation on cotton at the Co-60 source at as, analyzing parameters such as fiber quality and yield parameters including lint percentage, staple length, fiber fineness (Micro-naire), fiber strength, seed yield and cotton yield. Improved varieties of cotton were selected from Cotton Research Institute, Multan and were treated with cobalt source at the rate of 0, 10, 15, 20 and 25 Krades. Three potential cotton varieties i.e Gomal-93, Bt-131 and Bt-CIM-602 previously irradiated @ 15, 20 and 25 KR respectively were selected from among the six varieties. Seeds of these three commercial varieties of cotton (G. hirsutum) were sown in May...

Journal of Thermoplastic Composite Materials, 2013

In this study, highly oriented self-reinforced wood–polymer composite (WPC) rods were produced by... more In this study, highly oriented self-reinforced wood–polymer composite (WPC) rods were produced by stable and continuous solid-state extrusion through a conical die. Polypropylene, softwood flour and inorganic filler were used at 50%, 40% and 10% weight concentration, respectively. The properties and morphology of the samples were studied by differential scanning calorimetry analyses, scanning electron microscopy observation and mechanics performance testing. Compared to a conventional extruded rod, the self-reinforced WPC rod profile exhibited a fibrillar structure largely parallel to the direction of extrusion, which contributed to the significantly high strength and modulus of the product as well as improved thermal properties and good dimensional stability. With the increase in draw ratio, the melting peak moved to high temperature, modulus (from 2200 to 5800 MPa) and strength (from 20.7 to 81.6 MPa) were greatly increased.

Most human societies assign different roles to men and women. gradually, due to change of family ... more Most human societies assign different roles to men and women. gradually, due to change of family structure and effective factors such as income level or level of education and women's contribution in the social fields and thought regarding equality of man and woman, family roles changed, that is men also were drawn to private field of family and cooperated with women in housework. This research tries to study the extent to which contribution is done by men in addition to studying social dimensions of housework division. This research started by use of survey method and questionnaire tool in 22 districts of Tehran city by selecting a sample of 200 married men and women with children. Sampling method was based on stratified sapling. On the basis of the results obtained form this research, one can find out that by stratifying social strata with education level criterion, the educated stratum has the most cooperation and contribution in housework and by increasing satisfaction with common life, cooperation and contribution in housework will increase. By studying on the obtained samples, effect of factors relating to family social relations network and socioeconomic base are visible in extent to which men contribute and cooperate.

3 Abstract: Dry seeds of four cotton varieties were irradiated with 0, 10, 15, 20 and 25 kR doses... more 3 Abstract: Dry seeds of four cotton varieties were irradiated with 0, 10, 15, 20 and 25 kR doses of gamma irradiation from Co source of gamma irradiation in 2012 at Nuclear Institute for Food and Agriculture (NIFA), 60

Journal of the Pakistan Institute of Chemical Engineers, Mar 6, 2023

Relative humidity is the prime parameter in industrial processes, which are measured through the ... more Relative humidity is the prime parameter in industrial processes, which are measured through the ceramic, metal oxide and polymeric sensors. Ceramic and metal oxide sensors show nonlinear resistive behaviours with increasing relative humidity and high sintering temperature for hydro-desorption. The transformation of ceramic and metallic sensors with polymeric sensors is due to its eco-friendly synthesis fabrication, less heatintensive and high sensitivity. In this research work, a polymeric sensor of enhanced electric properties with sustainable captive and resistive response was synthesised from nano-fibres graphene oxide for sensing humidity. The synthesized graphene oxide through the modified Hammer method was mixed with poly-vinyl alcohol (GO/PVA) in the ratio of 5 wt % for four hours at 90 ºC. Nano fibres of graphene oxide and poly-vinyl alcohol (GO/PVA) solutions were obtained at the 24V DC electric field; 0.5 ml/h feed rate and 10 cm tip-tocollector distance through electrospinning. GO/PVA fibres were deposited on the silver inter-digited electrodes of 8mm and five combs of 20ìm consecutive distance. SEM analysis shows that the fibres were in the nano-range with no major cracks while XRD and FTIR spectrum investigated the fingerprints and functional groups of GO and GO/PVA respectively. The parametric study of resistive and capacitive was analysed at different response and recovery times at various frequencies in the range of 0 % to 82% relative humidity.

Journal of Porous Materials

The original article has been corrected. Publisher's Note Springer Nature remains neutral with re... more The original article has been corrected. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Separation Science and Technology

Journal of Porous Materials

Journal of the Pakistan Institute of Chemical Engineers

In this work, nickel was deposited on copper substrate through electrodeposition which was abstra... more In this work, nickel was deposited on copper substrate through electrodeposition which was abstracted from local sulphate salt. Nickel deposition on copper substrate was done in both presence of vitamin C and saccharin additive. Boric oxide was used as buffering agent and pH of the solution bath was maintained through sulfuric acid and ammonium hydroxide. Round shape deposition on copper substrate was observed in the presence of vitamin C, while columnar shape particles were observed in the presence of saccharin additive. Deposition of nickel was done through sulfate bath on copper substrate. Boric acid was used as buffering agent and direct current electrolysis were conduct throughout this experimental work. pH of the solution was kept constant with the help of diluted sulfuric acid and ammonium hydroxide. The deposited nickel particles were obtained in round shape in the presence of vitamin additive, while columnar shape particles obtained in saccharin additive. The experimental c...

Journal of the Pakistan Institute of Chemical Engineers, Oct 13, 2021

Journal of the Pakistan Institute of Chemical Engineers, Oct 7, 2021

SSRN Electronic Journal, 2022

Materials Research Express, 2021

Quest for alternate energy sources is the core of most of the research activities these days. No ... more Quest for alternate energy sources is the core of most of the research activities these days. No matter how small or large amount of energy can be produced by utilizing the non-conventional techniques and sources, every bit of innovation can reshape the future of energy. In this work, experimental analysis of the thermoelectric (TE) properties of bulk-graphene in the temperature range of (303 to 363) K is presented. Graphene powder was pressed to form a pellet which was used to fabricate the TE device. The effects of temperature on the Seebeck coefficient, electrical and thermal conductivities, and the dimensionless figure of merit (FOM) were measured. The increasing value of the Seebeck coefficient (thermopower) with temperature is indicant of the metallic behavior. Additionally, the observed thermopower (TEP) is positive, which shows that the majority charge carriers are holes and peaked to a value of 56 μV K−1 at 363 K. The thermopower of the pellet is four times larger than the ...

Materials Research Express, 2021

Ceramic membranes are considered superior over their polymeric counterparts for applications at h... more Ceramic membranes are considered superior over their polymeric counterparts for applications at high temperature, pressure, and in aggressive environments with additional advantages of cleaning at high temperature. Preparation of porous ceramic membrane is expensive because the ceramic materials cannot be processed in a liquid state as polymers. Ceramic membrane synthesis involved solid powder preparation, consolidation, suspension formation, calcination, and sintering temperature which makes its synthesis very expensive. Geopolymerization is a heterogeneous reaction of aluminosilicate materials and chemical activators to form a three-dimensional structure having high mechanical strength without sintering. The overall percent energy and cost-saving of geopolymeric membranes were compared with conventional ceramic membranes. Recently, the geopolymerization technique has been used for membrane synthesis to replace conventional ceramic membrane synthesis. The objective of this review a...

Materials Research Express, 2021

Recently, metal halide perovskite materials for solar cells have gained a wonderful attention fro... more Recently, metal halide perovskite materials for solar cells have gained a wonderful attention from researchers around the world. In this paper, a novel perovskite layer in combination with other layers is numerically investigated to enhance the performance of perovskite-based solar cells (PSCs). General-purpose photovoltaic device model (GPVDM) is used to simulate the proposed structure with Methylammonium Lead Iodide (CH3NH3PbI3), sandwiched between a bi- and tri-layer. The results show enhanced short circuit current density (J sc ) and power conversion efficiency (PCE) for PSCs. The proposed PSCs show a Jsc of 39.6 mA cm−2 and PCE 31.4% under standard AM 1.5 G. The bi- and tri-layer sandwiched CH3NH3PbI3 structure is an elegant solution for the realization of high efficiency PSCs.

Materials, 2019

Liquid exfoliated molybdenum disulfide (MoS2) nanosheets and polyaniline (PANI) nanoparticles are... more Liquid exfoliated molybdenum disulfide (MoS2) nanosheets and polyaniline (PANI) nanoparticles are dispersed in polystyrene (PS) matrix to fabricate hybrid polymer composites with high dielectric and electromagnetic interference (EMI) shielding behavior. A phase-separated morphology is formed when PANI and MoS2 are incorporated into polystyrene (PS) matrix. An increasing concentration of MoS2 nanoparticles inside PS/PANI (5 wt %) polymer blend forms an interconnected network, resulting in high electrical conductivity and dielectric behavior, making them a suitable candidate for EMI shielding application. An increment in dielectric constant and loss, up to four and five orders of magnitude, respectively, is recorded at a maximum concentration of 1 wt % of MoS2 in PS/PANI-5 polymer blend at 100 Hz. The enhanced dielectric characteristics for PS/PANI/MoS2 composites are then theoretically evaluated for the estimation of EMI shielding effectiveness in the frequency range of 100 Hz to 5 M...

Several studies have been conducted on radiation effects on organisms. Although most of the inter... more Several studies have been conducted on radiation effects on organisms. Although most of the interest has been on humans, yet during the last few years increasing attention has been directed to other organisms, focusing on an ecosystem perspective with the intention of defining safe levels of radiation. In this study, we looked at low dose effects of gamma radiation on cotton at the Co-60 source at as, analyzing parameters such as fiber quality and yield parameters including lint percentage, staple length, fiber fineness (Micro-naire), fiber strength, seed yield and cotton yield. Improved varieties of cotton were selected from Cotton Research Institute, Multan and were treated with cobalt source at the rate of 0, 10, 15, 20 and 25 Krades. Three potential cotton varieties i.e Gomal-93, Bt-131 and Bt-CIM-602 previously irradiated @ 15, 20 and 25 KR respectively were selected from among the six varieties. Seeds of these three commercial varieties of cotton (G. hirsutum) were sown in May...

Journal of Thermoplastic Composite Materials, 2013

In this study, highly oriented self-reinforced wood–polymer composite (WPC) rods were produced by... more In this study, highly oriented self-reinforced wood–polymer composite (WPC) rods were produced by stable and continuous solid-state extrusion through a conical die. Polypropylene, softwood flour and inorganic filler were used at 50%, 40% and 10% weight concentration, respectively. The properties and morphology of the samples were studied by differential scanning calorimetry analyses, scanning electron microscopy observation and mechanics performance testing. Compared to a conventional extruded rod, the self-reinforced WPC rod profile exhibited a fibrillar structure largely parallel to the direction of extrusion, which contributed to the significantly high strength and modulus of the product as well as improved thermal properties and good dimensional stability. With the increase in draw ratio, the melting peak moved to high temperature, modulus (from 2200 to 5800 MPa) and strength (from 20.7 to 81.6 MPa) were greatly increased.

Most human societies assign different roles to men and women. gradually, due to change of family ... more Most human societies assign different roles to men and women. gradually, due to change of family structure and effective factors such as income level or level of education and women's contribution in the social fields and thought regarding equality of man and woman, family roles changed, that is men also were drawn to private field of family and cooperated with women in housework. This research tries to study the extent to which contribution is done by men in addition to studying social dimensions of housework division. This research started by use of survey method and questionnaire tool in 22 districts of Tehran city by selecting a sample of 200 married men and women with children. Sampling method was based on stratified sapling. On the basis of the results obtained form this research, one can find out that by stratifying social strata with education level criterion, the educated stratum has the most cooperation and contribution in housework and by increasing satisfaction with common life, cooperation and contribution in housework will increase. By studying on the obtained samples, effect of factors relating to family social relations network and socioeconomic base are visible in extent to which men contribute and cooperate.

3 Abstract: Dry seeds of four cotton varieties were irradiated with 0, 10, 15, 20 and 25 kR doses... more 3 Abstract: Dry seeds of four cotton varieties were irradiated with 0, 10, 15, 20 and 25 kR doses of gamma irradiation from Co source of gamma irradiation in 2012 at Nuclear Institute for Food and Agriculture (NIFA), 60