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In Pakistan raw coal and a little quantity of waste plastics are burnt to sustain high temperature inside brick making kilns. The gaseous emissions of the kilns contain a considerable amount of darkish colored particulates. It is currently believed that the plastic burning produces these particulates. Advanced characterization instruments, such as a scanning electron microscope, energy dispersive spectroscopy, X-ray fluorescence, X-ray diffractometer, surface area analyzer using nitrogen gas adsorption isotherms, and thermogravimetric analyzer, were used to find out the chemistry and physics of the particulates. At a magnification of 30,000x, the SEM picture shows masses that are roughly roundish in shape and their size is in between 0.1 to 0.5 microns. The elements detected in these particles are carbon, oxygen, and sulfur (EDS analysis), or in other words, these elements are a typical composition of raw coal. This elemental analysis suggest that fine coal particles come out with usual combustion gases and these emitted particulates are not plastic combustion product. To strengthen this finding, the sample when calcined discarded a significant amount of sulphur oxides species, as determined in the XRF study by noticing a considerable decrease of sulphur content in the calcined particles, suggesting that the particles are actually a coal. The N2 isotherm graph reveals that the light weight flying coal particles has a very low surface area. Additionally, the XRD and TGA studies supports the conclusion that these dark colored particulate emissions are primarily fine coal particles (cenosphere). [ABSTRACT FROM AUTHOR]

The present study carries out the sedimentological and diagenesis impact on reservoir quality of the Early Jurassic sandstone (Datta Formation) of Trans-Indus Ranges, Pakistan. To fulfill the objectives of the present study Pezu & Abbo Wanda sections have been selected. To evaluate the reservoir characteristics the thin section analysis, scanning electron microscope (SEM), SEM, cathodoluminescence (CL), X-ray diffraction (XRD), and core plug porosity and permeability analysis have been used. Field evidence shows that there are four depositional facies six lithofacies, and three microfacies, with different sedimentary structures, were observed, which indicates that Jurassic sandstone has been deposited in a deltaic environment. Petrographic analysis and SEM show compaction is moderate to high, and grain binding calcite cement with subordinate quartz overgrowth and hematite. Feldspar dissolution and clay minerals precipitation were important diagenetic reactions that influenced the quality of the reservoir. Primary intergranular pores, fractured, and dissolution pores are present within the studied sections. Overall, pores connectivity is good, and at some places, the quality of the pores has been affected by authigenic clay minerals. SEM analysis predicts that clay minerals like kaolinite, smectite, and Illite/smectite are common pore-filling minerals that reduce the reservoir quality. Primary pores, fractures, dissolution pores, as well as core plug porosity and permeability data (porosity 15.90 to 27.01% and permeability 0.15 to 150 mD) predict that Jurassic sandstone has good reservoir characteristics. [ABSTRACT FROM AUTHOR]

Heavy structures built on untreated collapsible soil remain susceptible to failure due to abrupt changes in the soil structure upon wetting. Industrial wastes like cement kiln dust (CKD) can be used to solve this problem. For this study, undisturbed and disturbed collapsible soil samples were collected from Thal Haro arid area, Punjab, Pakistan. CKD was mixed up to 20% to stabilize the collapsible soil with a maximum of 28 days of curing time. To perform strength tests and collapsible potential tests, samples were remolded at optimal water content and maximum dry unit weight. The CKD content exponentially improves the unconfined compression strength, deformation modulus, and soaked California bearing ratio; however, it marginalizes the ductility of treated soil. With the addition of CKD, the strain at failure and deformability index is significantly decreased. Moreover, for microstructural characteristics comparison, X-ray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDAX) analyses were performed on untreated and treated samples. Due to the addition of CKD, XRD and EDAX results show the new peaks of calcium and calcium silicate, respectively, in treated samples. The formation of the new element and compound indicates the generation of bonds among soil partials owing to the hydration and pozzolanic reactions which is also verified by the SEM results. The SEM analyses manifest the conversion of the dispersed and silt-dominated structure of the native collapsible soil to a reticulated structure without micropores due to the addition of CKD. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the elemental composition of the hard shell of the three-spot swimming crab, Portunus sanguinolentus, collected from the coasts of Pakistan. Thirty crab shells were collected and divided into three groups considering their size. The element detection was performed by energy-dispersive X-ray spectroscopy with scanning electron microscope (SIM/EDAX). The mean concentration of carbon, oxygen, calcium, copper, magnesium, and phosphorus observed in the shell of P. sanguinolentus was 13.63 ± 6.21%, 46.25 ± 12.62%, 34.39 ± 18.33%, 3.19 ± 1.25%, 1.15 ± 0.99%, and 1.39 ± 0.51%, respectively. The concentration pattern of these observed elements in P. sanguinolentus shells was found in the following order: O > Ca > C > Cu > P > Mg. To compare among the three groups of shells, the highest concentration of calcium (54.60%) was obtained in large-sized shell groups, which was significantly different from the other groups (p < 0.05). A high concentration of copper was found to be accumulated in the large-sized (3.55%) and medium-sized (4.21%) shell groups, which was significantly higher than in small-sized shell groups (p < 0.05). In the case of the large-sized shell group, the mean concentrations of magnesium and phosphorus were significantly lower than the medium-sized shell group (p < 0.05). The results indicate that crab shells could act as a good bio-sorbent for several minerals in its ecosystem. P. sanguinolentus shell is very rich in calcium, magnesium, and phosphorus. Extraction of calcium, magnesium, and phosphorus from P. sanguinolentus shells could be profitable for biofertilizer and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

This study aims to determine the interdependence of deposition, tectonics and diagenesis in a prolific hydrocarbon reservoir. This has been achieved through an integrated field study, petrography, scanning electron microscope (SEM), zircon microscopy and X-ray diffraction (XRD) in the fluvio-deltaic sandstone of the Lower Cambrian Khewra Sandstone. Sandstones are subarkose, sublitharenite and feldspathic litharenite subjecting to compaction, cementation, dissolution and replacement. The pore types are intergranular, vuggy, and fractures. The paragenetic sequence suggests a multistage diagenetic history for the sandstone under eogenetic, mesogenetic and telogenetic regimes. The telogenetic alterations are triggered by Himalayan orogeny. Both deposition and tectonics control the spatial and temporal distribution of diagenetic facies and sweet spots. The bounding unconformities and variation of compositional and textural patterns determine the reservoir quality. The dynamic interaction among deposition, tectonics and diagenesis yields a comprehensive understanding of reservoir potential on a global scale. [Display omitted] • The Lower Cambrian Khewra Sandstone is diagenetically heterogeneous sandstone. • It is bounded by unconformities and deposited in fluvio-deltaic environment. • The eodiagenetic, mesodiagenetic and telodiagenetic alterations involve compaction, cementation, dissolution and replacement. • Deposition and diagenesis control the reservoir quality of Khewra Sandstone. • The coarse-grained texture and meteoric water percolation from overlying unconformity make the upper sandstone a potential hydrocarbon reservoir. [ABSTRACT FROM AUTHOR]

The work focuses on the removal of Arsenic-III (As(III)) from water sample by an indigenous iron ore from Balochistan by adsorption method. Three iron ore samples were analyzed by X-Ray Diffractometer (XRD) and a sample from Shikarap containing iron 36.2% was selected because it contained the highest amount of hematite. The batch study was conducted to examine the adsorption by iron ore and maximum adsorption was observed at pH 6, 1/2 g dose per 50 mL solution, contact time 2 hr and shaking speed 150 rpm. At the optimized conditions, the removal was 89% when monitored at 50 μg L-1 initial concentration of arsenic. The arsenic removal was monitored by Atomic Absorption Spectrometer (AAS) using hydride generation. Dubinin - Radushkevich (D-R), Freundlich and Langmuir's isotherms were examined. The highest adsorption capacity of iron ore for As(III) removal was observed 13.67 μg g-1 by Langmuir model and Freundlich isotherm indicated good adsorption intensity with value n = 1.512. Thermodynamic parameters revealed that adsorption was exothermic and physisorption. The Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray (EDX) techniques were applied to scan the surface morphology and the percentage elemental composition of samples respectively. SEM results demonstrated that Shikarap mineral grains are an oval shape and these were changed after the uptake of As(III). The EDX spectra of Shikarap mineral confirm the As(III) adsorption on particles as As 4.19%. [ABSTRACT FROM AUTHOR]

Cuscuta reflexa Roxb. belonging to family Cuscutaceae was explored for its pollen morphology and its pollen characters examined with light and scanning electron microscope were compared with six species belonging to family Convolvulaceae. Pollen samples were collected from Districts; Kotli, Bhimber and Mirpur, Azad Jammu & Kashmir, Pakistan. Flowers of Cuscuta reflexa Roxb., five species of Ipomoea including Ipomoea carnea Jacq., Ipomoea cairica (L.) Sweet, Ipomoea hederacia Jacq., Ipomoea pes-tigridi sL., Ipomoea eriocarpa R.Br., Ipomoea arachnosperma Welw. and Convolvulus arvensis L. were collected. Pollen shape of these selected species are generally prolate, subprolate, prolate-spheroidal, oblate spheroidal and perpolate. The apertures of the pollens of these taxa were found scabrate, scabrate-perforate, reticulate and echinate-reticulate. Among the examined taxa, C. reflexa Roxb. has smallest size of pollen (2-5×2.5-5pm) while the largest pollen (28.5-37.6 × 24.7-28.9pm) belongs to the Ipomoe acarnea. It has been founded that pollen of Cuscuta reflexa Roxb. is prolate in shape and was similar to I. carnea Jacq, I. pes-tigridis L, I. eriocarpa R.Br pollens. Hierarchical cluster analysis based on pollens observations grouped I. arachnosperma and Cuscuta refelexa together at maximum similarity 99.86 at a distance level of 0.003. It has been concluded from this study that Cuscuta refelexa pollen are exactly similar to Ipomea arachnosperma on the bases of pollen morphology and exine appearance. [ABSTRACT FROM AUTHOR]

This paper has reported physicochemical features of mild steel's corrosion products and provided atmospheric corrosivity maps of Karachi harbor city, drafted on the basis of spatial distribution of corrosion data from July 2018 to June 2019 at 10 different urban, industrial, and marine test sites. Exposure tests have been performed to study atmospheric corrosivity, corrosion products, and corrodants including chloride, sulfur dioxide, time of wetness (TOW), and corrosion rate as per ISO and ASTM standards. Scanning electron microscope, Fourier‐transform infrared spectroscopy, and X‐ray diffraction have corroborated the presence of lepidocrocite, goethite, magnetite, and quartz phases at almost all the test sites, with slight variations in their morphologies and quantities. The data analysis has revealed that TOW is a major detrimental factor to accelerate corrosion of mild steel at Karachi city. The corrosivity category of all urban and marine test sites is found in C4–C5 range, whereas for industrial test sites, it is found in C3–C5 range. Resultant corrosivity maps have shown that the prevailing atmosphere is significantly corrosive at Karachi harbor city. This study has furnished a novel product of atmospheric corrosivity map, which is the first‐ever corrosivity map for Pakistan. [ABSTRACT FROM AUTHOR]

This paper characterizes the sugarcane bagasse ash as a pozzolan and investigates its influence on the hardened properties of concrete. In Pakistan, the sugar industry recycles raw bagasse for power generation, and as a result, tonnes of bagasse ash are produced every year. For this study, the bagasse ash sample was obtained from one of the local sugar mills of Pakistan. The physical, chemical and mineralogical of bagasse ash were investigated by employing X-ray diffraction (XRD), X-ray fluorescence and laser particle size techniques, while the microstructure was studied through scanning electron microscope. In addition, the evaluation of hardened properties like compressive strength, tensile strength, flexural strength and thermal conductivity was also carried out. Here, the concrete mixtures were prepared by replacing the cement with bagasse ash in the ratio of 5 to 30% (by weight). The chemical, physical and mineral results reveal that this local bagasse ash has all pozzolanic properties. The evidence of amorphous and crystalline phases was found in the XRD pattern, along with silicon dioxide (SiO2) which was recorded more than 70% in the ash. It was observed that the workability for bagasse ash-blended concrete mixtures increases with ash content. Furthermore, the bagasse ash mixtures with 10% substitution were found optimal for achieving higher compressive, flexural and tensile strength, while the thermal conductivity showed a consistent drop with higher ash content percentage. [ABSTRACT FROM AUTHOR]

The adsorption of methylene blue was carried out by adsorbent prepared from Acacia modesta. The sample wood was collected from Dir lower Khyber Pakhtunkhwa Pakistan. Chemical activation of the sample was conducted for surface efficiency. Surface of raw and activated sample was elucidated by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared (FTIR) techniques. Adsorption of methylene blue was studied on raw and activated samples by kinetics adsorption at different adsorption temperatures such as 20 °C, 30 °C and 40 °C. The adsorption equilibrium was established within 2 h. Elovich, Bhangam, and Parabolic diffusion equations were applied to the adsorption kinetics data and were found fit for adsorption. From adsorption kinetic data the parameters like ΔH=/, ΔS=/and ΔE=/were calculated and showed that the adsorption process was spontaneous process. Entropy in descending order shows that dye molecules adsorbed in an oriented position. [ABSTRACT FROM AUTHOR]

Zard Koh and Kulli Koh are two recently discovered iron ore deposits, existing in the Chagai district, Balochistan, Pakistan. PSM (Pakistan Steel Mill Limited) is interested to utilize these ore deposits at priority. Purpose of the present study was to assess the mineralogy of the Zard Koh and Kulli Koh iron ore deposits, as it plays a vital role in the selection of an appropriate processing method. The mineralogical study of ore deposits was carried out by XRD (X-Ray Diffraction), XRF (X-Ray Fluorescence), SEM (Scanning Electron Microscope) attached with EDS (Energy Dispersive Spectroscope) and SM (Stereomicroscope) techniques. Results indicated that the Zard Koh ore is mainly composed of 60.15% maghemite, 23.57% pyrite, 4.07% chlorite, 10.30% grossular and 1.65% admontite minerals. The chemical analysis revealed that Zard Koh iron ore contains an average of 54.27% Fe, 12.73% S, 8.70% Si, 3.07% Al, 4.07% Ca, and 2.16% Mg. Similarly, the mineralogical study of the Kulli Koh iron ore indicated that, ore is containing 51.16% hematite, 29.24% quartz, 8.89% dravite, and 8.76% kaolinite minerals. Elemental analysis of different samples indicated that Kulli Koh iron ore contains an average composition of 40.23% Fe, 20.67% Si, 3.44% Ca, 3.81% Al and 3.25% Mg. Mineralogical study of the Zard Koh and Kulli Koh iron ore deposits suggested that these ore deposits can be beneficiated costeffectively by using magnetic separation techniques. [ABSTRACT FROM AUTHOR]

In this study thermoluminescence characteristics of the pink Himalayan salt has been studied. For this purpose, pellets of pink Himalayan salt weighing 40 mg were prepared. The ICP-OES and EDX analytical techniques were used to find the elemental composition of the sample. It confirms the presence of Al, Mg, Ca, Sr, S, Zn, K, Mn and Fe etc. along with the main matrix. The XRD analysis shows that the salt has face centered cubic (FCC) structure with average crystallite size of 70.6 nm. The scanning electron microscope (SEM) was used for surface morphology. To investigate the thermoluminescence properties, the pellets were irradiated with 137Cs source in the dose range of 1–5000 mGy. The glow curve indicated the presence of three peaks namely P1, P2 & P3 with two very prominent peaks occurring at 135 °C and 260 °C. The T max -T stop procedure revealed the coinciding peaks in the glow curve and their relative positions. The trapping/kinetic parameters, such as electron trap depth (E), order of kinetic (b) and frequency factor (s) were explored by employing CGCD technique. The values of figures of merit (FOM) calculated at different doses (500 mGy, 1 Gy, 2 Gy & 5 Gy) were found to be 1.14%, 1.24%, 1.11% and 1.13% respectively. This indicates excellent agreement between the experimental and theoretical fitting. The post irradiation fading of the sample pellets were studied at dose of 500 mGy for different time intervals up to 8 week and 30% loss in TL signal was observed within first 24 h which becomes stable after 2 week. On the basis of these results it can be concluded that pink Himalayan salt has a potential to be used in radiation dosimetry. • Thermoluminescence of Pink Himalayan NaCl (salt) of Pakistan. • Determination of kinetic parameter. • Glow curves, Dose response, T m -T stop and CGCD. [ABSTRACT FROM AUTHOR]

The deposition of trace and major elements from the atmosphere to the ground is an important factor for plants, animals and humans as well. Total suspended particulate matter was measured by a standard gravimetric technique. A scanning electron microscope was used for the evaluation of the size distribution and morphological structures of the aerosol particulates trapped on the surface of filter paper. The aerosol particulates were studied by a scanning electron microscope at various magnification. The trace elemental composition in the atmosphere of Faisalabad was studied by using instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS). Concentrations of 23 trace elements and a major one were determined in samples of aerosol particulates collected during a longe sampling period in the atmosphere at Faisalabad, Pakistan. Their amount was two times higher than the limits adopted by the U.S. Environmental Protection Agency for the urban environment. [ABSTRACT FROM AUTHOR]

The objective of this study is to highlight the stress factors influencing primary school female teachers in southern Punjab, Pakistan. A causation model is developed to determine the effect of the three main domains of stress. Data were collected through a questionnaire using a convenient sampling technique. Cronbach's alpha is computed to determine the internal consistency of the items of the questionnaire. The factors involved in the causation model are confirmed through confirmatory factor analysis. The perceived stress scale is used to check the stress level in primary school female teachers. A structural pathway of social, health and environmental factors is designed to determine the influence of different variables on stress. The examined problems included the four following major areas: social factors, economic factors, health factors and environment factors. Among our results, it is shown that the marital status has an effect on the stress level of both public and private female school teachers. [ABSTRACT FROM AUTHOR]