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31.
Shahid Naseem Pazeer Ahmed Syeda Sadia Shamim Erum Bashir 《Environmental Earth Sciences》2012,66(7):1831-1838
This paper is an attempt to study the geochemistry of Akra Kaur Dam (AKD) water, north of Gwadar city, southern Balochistan. Representative water samples were collected from AKD reservoir to assess the suitability of water for drinking and agriculture purposes. The major ionic composition is suggestive for freshwater. The average ionic composition demonstrate SO4 > Ca > Na > Cl > HCO3 > Mg > K. The plots on Piper diagram reflected Ca–Mg–SO4 type of water facies. High Ca/SO4 and Ca/Mg ratios revealed that the water has influence of gypsum dissolution. The negative ratio of chloro-alkaline indices indicated reverse exchange between Ca and Mg in water occurred with Na and K in rocks. The pH, electrical conductivity, total dissolved salts, Ca, Mg, Na, K, HCO3, Cl and SO4 concentrations in the dam water were below the permissible limit, however, Na and SO4 were above the desirable limit, set by the World Health Organization. Important parameters such as residue sodium carbonate, sodium percent, sodium adsorption ratio, permeability index, magnesium content and Kelley’s ratio were calculated to evaluate the suitability of water for irrigation purpose. The result were compared with standard permissible limits and found satisfactory. The health and agriculture hazards of sulphate-bearing water were also discussed. 相似文献
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Elemental characterization of black shales of Khyber Pakthunkhawa (KPK) region of Pakistan using AAS 总被引:1,自引:0,他引:1
Black shale samples were collected from Chimiari Khyber Pakthunkhawa region of Pakistan and were analyzed for elemental compositions. Atomic Absorption Spectrophotometry (AAS) was utilized for the determination of elements in the digested solutions. The analysis of black shale was performed precisely with relative standard deviation (RSD) lower than 2%. Results showed that the samples contained high concentrations of Ca (11.98 %), Al (7.09%), Fe (3.03%), Mg (0.59%) and Ti (0.58%). 相似文献
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Drinking quality assessment of some groundwater sources along the stretch of Jhelum River in Kashmir Himalaya 总被引:1,自引:0,他引:1
Rifat Ara Wani Bhat Mohd Skinder Aasimah Tanveer Bashir Ahmad Ganai 《Environmental Earth Sciences》2017,76(18):630
The physicochemical properties and major ion chemistry of the groundwater sources from alluvial aquifers along the stretch (60 km) of Jhelum River in Kashmir Himalaya were determined in order to identify hydro-geochemical processes and their suitability for drinking purposes. The data depicted that calcium and bicarbonates were dominating among the cations and anions. The results indicate the trend of cation dominance as Ca2+ > Na+ > Mg2+ > K+, whereas anion dominance was in the order of HCO3 ? > Cl? > SO4 2?. Ratio of calcium to magnesium indicated the dissolution of Ca2+ from CaCO3, which results in an increased levels of Ca2+ in the groundwater. Interpretation of Piper Trilinear plot understands the various geochemical processes affecting the groundwater quality and shows groundwater was dominated by Ca–HCO3 type. The pH was recorded in the slightly alkalinity range 7.2–7.8 and was showing positive correlation with HCO3 ?. The chloro-alkaline indices revealed 86% of the sources exchange by a type of base-exchange reactions, rest by cation–anion exchange. Gibbs diagram revealed groundwater sources fall in the category of rock dominance. The concentration of the nitrogen compounds was in the progression of NO3–N > NH4–N > NO2–N, and the PO4 ? fluctuated from 0.12 to 0.22 mg/L. Moreover, corrosivity ratio indicated that water from the majority of sources (71%) is safe to supply using pipes without any corrosive effects, while 29% of sources are corrosive in nature and need non-corrosive pipes for transporting and lifting of groundwater. The results revealed, groundwater samples were within permissible limits as prescribed by International and National standards, for drinking purposes. The State government and NGO’s can show their interest in utilizing such water resources to overcome the shortage of drinking water in a sustainable way for the daily consumption of the people living in the vicinity of Jhelum River. 相似文献
34.
Dynamic flow systems and transport of contaminants in karstic aquifers result from the actions of physical and chemical processes involving aqueous systems containing certain contaminants. These processes are elaborated, and pertinent mathematical and chemical equations are discussed, herein. Contaminant transport in karstic aquifers can be mathematically expressed by the basic equations evaluated primarily for the flow in porous, highly permeable aquifers. The effects of advection, hydrodynamic dispersion, and dilution are elaborated as physical processes that effect the movement of contaminants through groundwater in permeable rocks. Physical and chemical mechanisms that govem contaminant movement and groundwater flow through fractured media are proposed as the basis of an approximate scenario of contaminant transport through karstified carbonate rocks. 相似文献
35.
Bashir A. Memon Asadullah Kazi William J. Powell A. S. Bazuhair 《Environmental Geology》1986,8(3):153-160
Groundwater recharge by natural replenishment for the unconsolidated alluvial aquifer in Wadi Al-Yammaniyah is estimated on
a daily basis instead of the conventional monthly basis The study reveals that during the two-year period (1978 and 1979),
the estimated recharge in the area is about 40% of the total average annual rainfall of 155 mm Subsurface underflow estimated
at 36×10−6 m3/yr from the Wadi Al-Yammaniyah aquifer occurs in the vicinity of Wadi Ash-Shamiyah A comparison of the recharge and extracted
volumes of water from the aquifer indicates that there is a net increase of 10 million m3 and 38 million m3 of water in the storage for 1978 and 1979, respectively 相似文献
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M. Younas M. Sohail L. K. Leong M. JK Bashir S. Sumathi 《International Journal of Environmental Science and Technology》2016,13(7):1839-1860
In the last few decades of industrialization, the concentration of CO2 in the atmosphere had increased rapidly. Different organizations have invested considerable funds in research activities worldwide for CO2 capture and storage. To date, significant work has been done and various technologies have been proposed for CO2 capture and storage. Both adsorption and absorption are promising techniques for CO2 capture, but low-temperature adsorption processes using solid adsorbents are the prevailing technique nowadays. In this review paper, a variety of adsorbents such as carbonaceous materials, dry alkali metal-based sorbents, zeolites, metal–organic frameworks (MOFs) and microporous organic polymers (MOPs) have been studied. Various methods of chemical or physical modification and the effects of supporting materials have been discussed to enhance CO2 capture capacity of these adsorbents. Low-temperature (<100 °C) adsorption processes for CO2 capture are critically analyzed and concluded on the basis of information available so far in the literature. All the information in CO2 adsorption using different routes has been discussed, summarized and thoroughly presented in this review article. The most important comparative study of relatively new material MOFs and MOPs is carried out between the groups and with other sorbent as well. 相似文献
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Water Resources - Hydrological runoff prediction in a reliable and precise manner contributes significantly to the optimal management of hydropower resources. Considering the importance of runoff... 相似文献
40.
Al Hasa phosphates constitute the second phosphatic deposit exploited by the Jordan phosphate Mines Company. To investigate the radioactivity of these phosphates, 13 samples of poor phosphatic rocks of an area not exploited at the present time were selected to commence with. This is not the place to discuss either the origin of phosphates in a general manner or Al Hasa phosphates in particular. The literature on the first is effectively voluminous. But as regards the latter, there is little written material. Only some short statements not surpassing the generalities are found in (Heimbach, 1962; Kemmer, 1964; Bender, 1968; Youssef et al., 1969; Reeves & Saadi, 1971). It is hoped that radioactivity studies, especially when integrated with other domains of investigation, might afford a good way of clarifying their origin. Moreover, should the occasion arise, they might serve as the beginning to researches concerning uranium recovery from these phosphates. 相似文献