Syed Ilyas | Allama Iqbal Open University (original) (raw)
Papers by Syed Ilyas
Polish Journal of Environmental Studies
The present work was conducted to develop an efficient solar dryer for improving date fruit quali... more The present work was conducted to develop an efficient solar dryer for improving date fruit quality of Khairpur, Pakistan. Three different dryers were developed i.e., a natural convectional solar dryer, direct solar dryer and an oven solar dryer comprising air velocity of 0.5 m/s, 0.6 m/s and 0.4 m/s respectively. The temperature inside the three dryers significantly increased with the increase in time interval from 2 to 10 hrs. An average temperature ranged from 40.4 to 41.4ºC after 2 hrs which was significantly higher (p<0.0001) than the air temperature outside (36.4ºC) the three dryers. Moreover, increased up to 47.9ºC after 10 hrs of interval. Average highest temperature recorded in oven dryer was 41.4, 41.9, 45.8, 41.8 and 47.9 after a time interval of 2, 4, 6, 8 and 10hrs respectively. The highest solar radiation was observed as 985 W/m 2 at 2:30 pm and average solar radiation was found to be 791 W/m 2. The highest percentage of total sugar (67.7%), non-reducing sugars (18.1%) and reducing sugars (49.54%), proteins (31%) and calcium quantity (32.59 µg/g) was found in conventional dryers, which was followed by (66.88%) of total sugars,(49.6%) of reducing sugars and (17.61%) non-reducing sugars in direct dryer and (2.19%) of proteins and (22.76) µg/g of calcium in oven dryer. The results revealed that the drying natural oven solar dryer provided a good quality dates with satisfactory and competitive to enforce convective solar drying process. The drying time found to be approximately 8 hours daily and total 5 days taken to complete process of drying dates presents the advantage of being able to avoid the discontinuity of the treatment and to discard the night conservation problems. Owing to its low cost and green energy use, this study offers an efficient alternative to convectional drying under open sunlight for making quality dates.
Surface Science, 2021
ABSTRACT Two-dimensional (2D) materials are considered to be next-generation materials due to the... more ABSTRACT Two-dimensional (2D) materials are considered to be next-generation materials due to their extraordinary electronic and optical properties. Particularly, the moderate band gap and high carrier mobility of 2D materials are highly desired for nanoelectronics applications. Herein, we explore the structural, electronic and optical properties of 2D Si3X (X=S or O) monolayers. The anisotropic monolayers are predicted to have direct bandgaps of 0.94 eV (Si3S) and 1.19 eV (Si3O) (determined using the Heyd, Scuseria, and Ernzerhof screened hybrid method) and exhibt strong optical absorption in the range of 106 cm−1. They are also predicted to have high electron and hole mobilities up to 0.5 × 103 cm2 V−1 s−1and 2.2 × 103 cm2 V−1 s−1. Due to the distinctive structural, electronic and optical properties, the 2D anisotropic Si3X monolayer is a promising material for future optoelectronic and nanoelectronic applications.
The intrinsic problems of toxicity and instability of lead solar cells have motivated extensive r... more The intrinsic problems of toxicity and instability of lead solar cells have motivated extensive research intended to develop alternative materials for photovoltaic applications. First-principles calculations were performed in order to shed light on replacing the Pb2+ cation in lead- and mixed-halide materials with a formula of Cs2X2Y2 (X, Y = F, Cl, Br, I). The calculated band gaps range from 0 eV to 3.188 eV, and the absorption coefficients from 6 to 16 × 104 cm−1. The band gap of Cs2Cl2I2 is close to the Shockley-Queisser limit and its absorption coefficient is in the visible frequency range, which, in conjunction with its easy and economical synthesis process, qualify it as an alternative lead-free material for fabricating solar cells. It is suggested for further work that if the ratio of halogens is adjusted then the band gaps of Cs2F2Cl2, Cs2Cl2I2, Cs2Br2I2, and Cs2I2F2 may be tuned to the desired electronic band gap limit required to improve their optoelectronic performance.
Brazilian Journal of Physics, 2021
Coatings
This work reports on the synthesis of small molecular semiconductor 2-(1H-pyrrol-1-yl)-anthracene... more This work reports on the synthesis of small molecular semiconductor 2-(1H-pyrrol-1-yl)-anthracene-9,10-dione (PAD) via wet chemical precipitation route method for its possible potential applications in sensors. Thin film characterization of the synthesized PAD is carried out by studying its surface morphology, bond dynamics, and optical properties. For studying sensing characteristics of the PAD, its 100 nm thick film is thermally deposited on pre-patterned silver (Ag) electrodes over glass substrate having ~45 µm inter-electrode gaps to prepare Ag/PAD/Ag sensor. The effects of humidity (%RH), temperature (T), and illumination of light (Ev) on the fabricated Ag/PAD/Ag sensor are studied by changing one of the three (%RH, T, and Ev) parameters at a time and measuring the corresponding variations in capacitance (C) and capacitive reactance (X) of the device. As C and X also depend on frequency, sensing properties of the Ag/PAD/Ag sensor are measured at two different frequencies (120 H...
Applied Physics Letters, 2002
We have prepared single-crystalline films of BaFeO3, which may contain high valent Fe4+ ions, on ... more We have prepared single-crystalline films of BaFeO3, which may contain high valent Fe4+ ions, on (100) SrTiO3 substrates by pulsed laser-beam deposition. The reflection high-energy electron diffraction patterns for the films apparently show a C4 symmetry operation, suggesting that the sample had a pseudocubic perovskite structure rather than hexagonal unit cell. The films were found to be highly insulating, and showed a high value of dielectric constant of e=59. At 300 K, the magnetization loop of the film apparently shows hysteresis, as well as small remanent magnetization. These characteristics are totally different from those of bulk BaFeO3.
Crystal Research and Technology, 2011
ABSTRACT Magnesium (Mg) doped lead titanate powders (PT: Mg) ceramics, with various Mg contents (... more ABSTRACT Magnesium (Mg) doped lead titanate powders (PT: Mg) ceramics, with various Mg contents (0, 2.5, 5, 7.5, 10, 12.5, 15, 17.5, 20, and 30 mole %), are prepared by the sol-gel method and characterized by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy. XRD results show that the magnesium diminishes the lattice tetragonality of PT:Mg. The average particle size and morphology were studied by SEM. The investigations done by Raman spectroscopy allow the analyzis of the substitution mechanism behavior related to the Mg incorporation into PT structure. A concentration threshold appears around 10% of Mg corresponding in a change of the compensation process with Mg2+ ions replacing Pb2+ ions below and both Pb2+ and Ti4+ above. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Journal of Magnetism and Magnetic Materials, 2017
Journal of nanoscience and nanotechnology, 2018
Green syntheses of nanoparticles using plant materials are of tremendous scope. Here we report ad... more Green syntheses of nanoparticles using plant materials are of tremendous scope. Here we report advantageous green synthesis for silver nanoparticles (AgNPs) using aqueous-root extract of Jurinea dolomiaea and AgNO3. Color change of solution and UV-Vis absorption at 444 nm indicated the formation of AgNPs. XRD confirmed their face centered cubic structure (fcc) with average particle size of 24.58 nm. SEM analysis showed their spherical, cubic and triangular structures. FT-IR indicated the presence of functional groups of reducing and stabilizing phytochemicals. Methanol-root extract of J. dolomiaea revealed high flavonoid (445 mg RE/g) and phenolic contents (92 mg GAE/g). Methanol-extract showed high antioxidant potency (IC50 = 0.494 μg/mL), rationally due to its high phenolic and flavonoid contents. These AgNPs showed the highest and equal antimicrobial activities against Escherichia coli and Pseudomonas aeruginosa (Inhibition zone 11.0 mm) whereas, methanol-roots extract showed equ...
Physica B: Condensed Matter
Abstract The manuscript demonstrated an annealing technique to modulate the thermoelectric proper... more Abstract The manuscript demonstrated an annealing technique to modulate the thermoelectric properties of GeSeIn thin films grown on Si substrate by thermal evaporation. The grown samples were annealed at various temperatures from 600 to 800 °C in air using programmable furnace to variation in Seebeck coefficient and power factor. The XRD data confirmed the amorphous nature of GeSeIn glasses because no XRD peak was observed in as grown sample. But annealing process developed a temporary crystalline phase of GeSe having (016) plane which again disappeared at annealing temperature 900 °C. Raman spectroscopy measurements revealed a strong peak at 520 cm−1 due to Si substrate along with the couple of other peaks which are related to GeSeIn structure. The Seebeck data suggested that as grown sample has highest value of Seebeck coefficient (120 μV/0C) but it decreased from 110 to 20 μV/0C as the annealing temperature increased from 600 to 800 °C. The decreased in Seebeck coefficient with annealing temperature is due to decrease of carrier concentration. The Hall measurements demonstrated that the value of electrical conductivity remains almost constant (110–115 S/cm) for all samples annealed at various temperatures. This constant value of electrical conductivity is due to decrease of carrier concentration and increase of carriers mobility with annealing temperature.
Journal of Plastic, …, 2008
Correcting earlobe deformities often presents an aesthetic challenge to the surgeon. The describe... more Correcting earlobe deformities often presents an aesthetic challenge to the surgeon. The described technique presents a simple, accurate and cost effective method of remodelling soft tissue defects of the earlobe using a soft splint.
Mathematical and Computer Modelling, 2009
Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5 show the behaviour between monthly average humidity and... more Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5 show the behaviour between monthly average humidity and temperature during 19931997 for Quetta (lat. 30 11 ′ N,long. 66 57 ′ E, altitude: 1799 m above sea level). The overall trend of humidity during summer becomes minimum and ...
World Applied Sciences Journal, 2006
Abstract: Quetta is like a cup shaped valley with an (lat. 30 11'N long. 66 57'E) is el... more Abstract: Quetta is like a cup shaped valley with an (lat. 30 11'N long. 66 57'E) is elevated at 1799 m above sea level and covered from all dry mountains [1]. Air pollution survey has been conducted for various types of vehicular, traffic, plying on the Siryab road, by taking ...
Abstract: Wind characteristics and available wind energy in Quetta and Karachi, Pakistan have bee... more Abstract: Wind characteristics and available wind energy in Quetta and Karachi, Pakistan have been analyzed. The mean monthly, yearly wind speeds and wind power have been determined. Monthly and annual wind speed distributions for each season are presented. The analysis shows that the monthly mean wind speed ranged from 1 1 2.5 to 4.7 m s and 2.4 to 6.9 m s for Quetta and Karachi, respectively. The possibility of utilizing wind as a source of energy is also discussed.
Energy Conservation and Use of Renewable Energies in the Bio Industries, 1982
Journal of Applied Sciences and Environmental …, 2010
Nowadays air over major cities throughout the world has become over burdened with gases produced ... more Nowadays air over major cities throughout the world has become over burdened with gases produced by automobiles. The death rate due to automobiles pollution is increasing rapidly in the metropolitan areas. With passage of time people realized that polluted air had serious effects on their health, climate and economics. Weather and climate have the integrated impact on human activities which are resulting in worldwide concentration of the particulate of environmental pollution viz. chloroflorocarbons (CFCs), carbon dioxide, methane, nitrogen oxide, lead and several other dust and gaseous particles.The rapid growth in motor vehicle activity in Pakistan and other rapidly industrializing low-income countries is contributing to high levels of urban air pollution, among other adverse socioeconomic, environmental, health, and welfare impacts. This paper first discusses the local, regional, and global impacts associated with air pollutant emissions resulting from motor vehicle activity, and the technological, behavioral, and institutional factors that have contributed to these emissions, in Pakistan. The paper then discusses some implementation issues related to various policy measures that have been undertaken, and the challenges of the policy context. Finally, the paper presents insights and lessons based on the recent Pakistan experience, for better understanding and more effectively addressing the transport air pollution problem in Pakistan and similar countries, in a way that is sensitive to their needs, capabilities, and constraints. @JASEM
... Estimated values of diffuse radiation to total solar radiation using different correlation sh... more ... Estimated values of diffuse radiation to total solar radiation using different correlation ships developed by Page, Iqbal, Liu and Jordan, and Hay are presented. ... M.Iqbal 0.43 0.52 0.55 0.54 0.53 0.52 0.52 0.43 0.5 0.48 0.5 0.65 ...
Wind data of twelve years have been analyzed for Quetta, Pakistan to produce the probability dist... more Wind data of twelve years have been analyzed for Quetta, Pakistan to produce the probability distributions. Data for Quetta station is recorded on hourly basis and converted into m s -1 . Distributions are considered on monthly and annual basis: final results are compared and show 70-80% probability of hourly wind speed greater than 2.0 m s -1 . The probability for occurrence of wind speed at any location in Quetta will help designing the diverse engineering parameters for wind turbines like Darrius or Savonius such as angle of attack on rotors, suitable gear system to make wind machines work even in clean spells, generators, length of rotors; cut-in, cut-out and rated wind speeds of rotors.
Renewable Energy, Technology and the Environment, 1992
2 Abstract: The wind energy potential in coastal areas of Balochistan, Pakistan is examined using... more 2 Abstract: The wind energy potential in coastal areas of Balochistan, Pakistan is examined using 3-hourly wind data. The speed duration and frequency curves are represented graphically to read its extreme wind speed and total number of hours for a particular wind speed every year. Annual mean wind speed for a period of five years (1999-2003), energy and power are determined; the mean wind speed ranging 3.2 m s mentioned in Table 1. 1 The analysis of this data indicates that the wind energy potential is high in coastal areas of Balochistan, Pakistan. The high potential is used and suitable for the use of wind energy for windmills and electricity for light for scattered population.
Polish Journal of Environmental Studies
The present work was conducted to develop an efficient solar dryer for improving date fruit quali... more The present work was conducted to develop an efficient solar dryer for improving date fruit quality of Khairpur, Pakistan. Three different dryers were developed i.e., a natural convectional solar dryer, direct solar dryer and an oven solar dryer comprising air velocity of 0.5 m/s, 0.6 m/s and 0.4 m/s respectively. The temperature inside the three dryers significantly increased with the increase in time interval from 2 to 10 hrs. An average temperature ranged from 40.4 to 41.4ºC after 2 hrs which was significantly higher (p<0.0001) than the air temperature outside (36.4ºC) the three dryers. Moreover, increased up to 47.9ºC after 10 hrs of interval. Average highest temperature recorded in oven dryer was 41.4, 41.9, 45.8, 41.8 and 47.9 after a time interval of 2, 4, 6, 8 and 10hrs respectively. The highest solar radiation was observed as 985 W/m 2 at 2:30 pm and average solar radiation was found to be 791 W/m 2. The highest percentage of total sugar (67.7%), non-reducing sugars (18.1%) and reducing sugars (49.54%), proteins (31%) and calcium quantity (32.59 µg/g) was found in conventional dryers, which was followed by (66.88%) of total sugars,(49.6%) of reducing sugars and (17.61%) non-reducing sugars in direct dryer and (2.19%) of proteins and (22.76) µg/g of calcium in oven dryer. The results revealed that the drying natural oven solar dryer provided a good quality dates with satisfactory and competitive to enforce convective solar drying process. The drying time found to be approximately 8 hours daily and total 5 days taken to complete process of drying dates presents the advantage of being able to avoid the discontinuity of the treatment and to discard the night conservation problems. Owing to its low cost and green energy use, this study offers an efficient alternative to convectional drying under open sunlight for making quality dates.
Surface Science, 2021
ABSTRACT Two-dimensional (2D) materials are considered to be next-generation materials due to the... more ABSTRACT Two-dimensional (2D) materials are considered to be next-generation materials due to their extraordinary electronic and optical properties. Particularly, the moderate band gap and high carrier mobility of 2D materials are highly desired for nanoelectronics applications. Herein, we explore the structural, electronic and optical properties of 2D Si3X (X=S or O) monolayers. The anisotropic monolayers are predicted to have direct bandgaps of 0.94 eV (Si3S) and 1.19 eV (Si3O) (determined using the Heyd, Scuseria, and Ernzerhof screened hybrid method) and exhibt strong optical absorption in the range of 106 cm−1. They are also predicted to have high electron and hole mobilities up to 0.5 × 103 cm2 V−1 s−1and 2.2 × 103 cm2 V−1 s−1. Due to the distinctive structural, electronic and optical properties, the 2D anisotropic Si3X monolayer is a promising material for future optoelectronic and nanoelectronic applications.
The intrinsic problems of toxicity and instability of lead solar cells have motivated extensive r... more The intrinsic problems of toxicity and instability of lead solar cells have motivated extensive research intended to develop alternative materials for photovoltaic applications. First-principles calculations were performed in order to shed light on replacing the Pb2+ cation in lead- and mixed-halide materials with a formula of Cs2X2Y2 (X, Y = F, Cl, Br, I). The calculated band gaps range from 0 eV to 3.188 eV, and the absorption coefficients from 6 to 16 × 104 cm−1. The band gap of Cs2Cl2I2 is close to the Shockley-Queisser limit and its absorption coefficient is in the visible frequency range, which, in conjunction with its easy and economical synthesis process, qualify it as an alternative lead-free material for fabricating solar cells. It is suggested for further work that if the ratio of halogens is adjusted then the band gaps of Cs2F2Cl2, Cs2Cl2I2, Cs2Br2I2, and Cs2I2F2 may be tuned to the desired electronic band gap limit required to improve their optoelectronic performance.
Brazilian Journal of Physics, 2021
Coatings
This work reports on the synthesis of small molecular semiconductor 2-(1H-pyrrol-1-yl)-anthracene... more This work reports on the synthesis of small molecular semiconductor 2-(1H-pyrrol-1-yl)-anthracene-9,10-dione (PAD) via wet chemical precipitation route method for its possible potential applications in sensors. Thin film characterization of the synthesized PAD is carried out by studying its surface morphology, bond dynamics, and optical properties. For studying sensing characteristics of the PAD, its 100 nm thick film is thermally deposited on pre-patterned silver (Ag) electrodes over glass substrate having ~45 µm inter-electrode gaps to prepare Ag/PAD/Ag sensor. The effects of humidity (%RH), temperature (T), and illumination of light (Ev) on the fabricated Ag/PAD/Ag sensor are studied by changing one of the three (%RH, T, and Ev) parameters at a time and measuring the corresponding variations in capacitance (C) and capacitive reactance (X) of the device. As C and X also depend on frequency, sensing properties of the Ag/PAD/Ag sensor are measured at two different frequencies (120 H...
Applied Physics Letters, 2002
We have prepared single-crystalline films of BaFeO3, which may contain high valent Fe4+ ions, on ... more We have prepared single-crystalline films of BaFeO3, which may contain high valent Fe4+ ions, on (100) SrTiO3 substrates by pulsed laser-beam deposition. The reflection high-energy electron diffraction patterns for the films apparently show a C4 symmetry operation, suggesting that the sample had a pseudocubic perovskite structure rather than hexagonal unit cell. The films were found to be highly insulating, and showed a high value of dielectric constant of e=59. At 300 K, the magnetization loop of the film apparently shows hysteresis, as well as small remanent magnetization. These characteristics are totally different from those of bulk BaFeO3.
Crystal Research and Technology, 2011
ABSTRACT Magnesium (Mg) doped lead titanate powders (PT: Mg) ceramics, with various Mg contents (... more ABSTRACT Magnesium (Mg) doped lead titanate powders (PT: Mg) ceramics, with various Mg contents (0, 2.5, 5, 7.5, 10, 12.5, 15, 17.5, 20, and 30 mole %), are prepared by the sol-gel method and characterized by X-Ray diffraction (XRD), scanning electron microscopy (SEM) and Raman spectroscopy. XRD results show that the magnesium diminishes the lattice tetragonality of PT:Mg. The average particle size and morphology were studied by SEM. The investigations done by Raman spectroscopy allow the analyzis of the substitution mechanism behavior related to the Mg incorporation into PT structure. A concentration threshold appears around 10% of Mg corresponding in a change of the compensation process with Mg2+ ions replacing Pb2+ ions below and both Pb2+ and Ti4+ above. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Journal of Magnetism and Magnetic Materials, 2017
Journal of nanoscience and nanotechnology, 2018
Green syntheses of nanoparticles using plant materials are of tremendous scope. Here we report ad... more Green syntheses of nanoparticles using plant materials are of tremendous scope. Here we report advantageous green synthesis for silver nanoparticles (AgNPs) using aqueous-root extract of Jurinea dolomiaea and AgNO3. Color change of solution and UV-Vis absorption at 444 nm indicated the formation of AgNPs. XRD confirmed their face centered cubic structure (fcc) with average particle size of 24.58 nm. SEM analysis showed their spherical, cubic and triangular structures. FT-IR indicated the presence of functional groups of reducing and stabilizing phytochemicals. Methanol-root extract of J. dolomiaea revealed high flavonoid (445 mg RE/g) and phenolic contents (92 mg GAE/g). Methanol-extract showed high antioxidant potency (IC50 = 0.494 μg/mL), rationally due to its high phenolic and flavonoid contents. These AgNPs showed the highest and equal antimicrobial activities against Escherichia coli and Pseudomonas aeruginosa (Inhibition zone 11.0 mm) whereas, methanol-roots extract showed equ...
Physica B: Condensed Matter
Abstract The manuscript demonstrated an annealing technique to modulate the thermoelectric proper... more Abstract The manuscript demonstrated an annealing technique to modulate the thermoelectric properties of GeSeIn thin films grown on Si substrate by thermal evaporation. The grown samples were annealed at various temperatures from 600 to 800 °C in air using programmable furnace to variation in Seebeck coefficient and power factor. The XRD data confirmed the amorphous nature of GeSeIn glasses because no XRD peak was observed in as grown sample. But annealing process developed a temporary crystalline phase of GeSe having (016) plane which again disappeared at annealing temperature 900 °C. Raman spectroscopy measurements revealed a strong peak at 520 cm−1 due to Si substrate along with the couple of other peaks which are related to GeSeIn structure. The Seebeck data suggested that as grown sample has highest value of Seebeck coefficient (120 μV/0C) but it decreased from 110 to 20 μV/0C as the annealing temperature increased from 600 to 800 °C. The decreased in Seebeck coefficient with annealing temperature is due to decrease of carrier concentration. The Hall measurements demonstrated that the value of electrical conductivity remains almost constant (110–115 S/cm) for all samples annealed at various temperatures. This constant value of electrical conductivity is due to decrease of carrier concentration and increase of carriers mobility with annealing temperature.
Journal of Plastic, …, 2008
Correcting earlobe deformities often presents an aesthetic challenge to the surgeon. The describe... more Correcting earlobe deformities often presents an aesthetic challenge to the surgeon. The described technique presents a simple, accurate and cost effective method of remodelling soft tissue defects of the earlobe using a soft splint.
Mathematical and Computer Modelling, 2009
Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5 show the behaviour between monthly average humidity and... more Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5 show the behaviour between monthly average humidity and temperature during 19931997 for Quetta (lat. 30 11 ′ N,long. 66 57 ′ E, altitude: 1799 m above sea level). The overall trend of humidity during summer becomes minimum and ...
World Applied Sciences Journal, 2006
Abstract: Quetta is like a cup shaped valley with an (lat. 30 11'N long. 66 57'E) is el... more Abstract: Quetta is like a cup shaped valley with an (lat. 30 11'N long. 66 57'E) is elevated at 1799 m above sea level and covered from all dry mountains [1]. Air pollution survey has been conducted for various types of vehicular, traffic, plying on the Siryab road, by taking ...
Abstract: Wind characteristics and available wind energy in Quetta and Karachi, Pakistan have bee... more Abstract: Wind characteristics and available wind energy in Quetta and Karachi, Pakistan have been analyzed. The mean monthly, yearly wind speeds and wind power have been determined. Monthly and annual wind speed distributions for each season are presented. The analysis shows that the monthly mean wind speed ranged from 1 1 2.5 to 4.7 m s and 2.4 to 6.9 m s for Quetta and Karachi, respectively. The possibility of utilizing wind as a source of energy is also discussed.
Energy Conservation and Use of Renewable Energies in the Bio Industries, 1982
Journal of Applied Sciences and Environmental …, 2010
Nowadays air over major cities throughout the world has become over burdened with gases produced ... more Nowadays air over major cities throughout the world has become over burdened with gases produced by automobiles. The death rate due to automobiles pollution is increasing rapidly in the metropolitan areas. With passage of time people realized that polluted air had serious effects on their health, climate and economics. Weather and climate have the integrated impact on human activities which are resulting in worldwide concentration of the particulate of environmental pollution viz. chloroflorocarbons (CFCs), carbon dioxide, methane, nitrogen oxide, lead and several other dust and gaseous particles.The rapid growth in motor vehicle activity in Pakistan and other rapidly industrializing low-income countries is contributing to high levels of urban air pollution, among other adverse socioeconomic, environmental, health, and welfare impacts. This paper first discusses the local, regional, and global impacts associated with air pollutant emissions resulting from motor vehicle activity, and the technological, behavioral, and institutional factors that have contributed to these emissions, in Pakistan. The paper then discusses some implementation issues related to various policy measures that have been undertaken, and the challenges of the policy context. Finally, the paper presents insights and lessons based on the recent Pakistan experience, for better understanding and more effectively addressing the transport air pollution problem in Pakistan and similar countries, in a way that is sensitive to their needs, capabilities, and constraints. @JASEM
... Estimated values of diffuse radiation to total solar radiation using different correlation sh... more ... Estimated values of diffuse radiation to total solar radiation using different correlation ships developed by Page, Iqbal, Liu and Jordan, and Hay are presented. ... M.Iqbal 0.43 0.52 0.55 0.54 0.53 0.52 0.52 0.43 0.5 0.48 0.5 0.65 ...
Wind data of twelve years have been analyzed for Quetta, Pakistan to produce the probability dist... more Wind data of twelve years have been analyzed for Quetta, Pakistan to produce the probability distributions. Data for Quetta station is recorded on hourly basis and converted into m s -1 . Distributions are considered on monthly and annual basis: final results are compared and show 70-80% probability of hourly wind speed greater than 2.0 m s -1 . The probability for occurrence of wind speed at any location in Quetta will help designing the diverse engineering parameters for wind turbines like Darrius or Savonius such as angle of attack on rotors, suitable gear system to make wind machines work even in clean spells, generators, length of rotors; cut-in, cut-out and rated wind speeds of rotors.
Renewable Energy, Technology and the Environment, 1992
2 Abstract: The wind energy potential in coastal areas of Balochistan, Pakistan is examined using... more 2 Abstract: The wind energy potential in coastal areas of Balochistan, Pakistan is examined using 3-hourly wind data. The speed duration and frequency curves are represented graphically to read its extreme wind speed and total number of hours for a particular wind speed every year. Annual mean wind speed for a period of five years (1999-2003), energy and power are determined; the mean wind speed ranging 3.2 m s mentioned in Table 1. 1 The analysis of this data indicates that the wind energy potential is high in coastal areas of Balochistan, Pakistan. The high potential is used and suitable for the use of wind energy for windmills and electricity for light for scattered population.