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1.
Chromium being one of the major toxic pollutants is discharged from electroplating and chrome tanning processes and is also found in the effluents of dyes,paint pigments,manufacturing units etc.Chromium exists in aqueous systems in both trivalent(Cr^3 )and hexavalent (Cr^6 )forms.The hexavalent form is carcinogenic and toxic to aquatic life,whereas Cr^3 is however comparatively less toxic.This study was undertaken to investigate the total chromium removal from industial effluents by chemical means in order to achieve the Pakistan NEQS level of 1 mg/L by the methods of reduction and precipitation.The study was conducted in four phase Ⅰ,the optimum pH and cost effective reducing agent among the four popular commercial chemicals was selected.As a result,pH of 2 was found to be most suitable and sodium meta bisulfate was found to be the most cost effective reducing agent respectively.Phase Ⅱ showed that lower dose of sodium meta hisulfate was sufficient to obtain 100% efficiency in reducing Cr^6 to Cr^3 ,and it was noted that reaction time had no significance in the whole process.A design curve for reduction process was established which can act as a tool for treatment of industrial effluents.Phase Ⅲ studies indicated the best pH was 8.5 for precipitation of Cr^3 to chromium hydroxide by using lime.An efficiency of 100% was achievable and a settling time of 30 minutes produced clear effluent.Finally in Phase Ⅳ actual waste samples from chrome tanning and electroplating industries,when precipitated at pH of 12 gave 100% efficiency at a settling time of 30 minutes and confirmed that chemical means of reduction and precipitation is a feasible and viable solution for treating chromium wastes from industries. 相似文献
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Usman Muhammad Murtaza Behzad Natasha Natasha Imran Muhammad Abbas Ghulam Amjad Muhammad Shahid Muhammad Ibrahim Sobhy M. Owens Gary Murtaza Ghulam 《Environmental monitoring and assessment》2022,194(2):1-30
Environmental Monitoring and Assessment - Few estuaries remain unaffected by water management and altered freshwater deliveries. The Caloosahatchee River Estuary is a perfect case study for... 相似文献
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Romshoo Shakil Ahmad Murtaza Khalid Omar Shah Waheed Ramzan Tawseef Ameen Ummer Bhat Mustafa Hameed 《Environmental science and pollution research international》2022,29(35):52732-52751
Environmental Science and Pollution Research - The Himalayan glaciers provide water to a large population in south Asia for a variety of purposes and ecosystem services. As a result, regional... 相似文献
4.
Amjad Adnan Randhawa Muhammad Atif Javed Muhammad Sameem Muhammad Zafarullah Ashraf Mussawar Ahmad Zulfiqar Murtaza Shamas 《Environmental science and pollution research international》2020,27(32):39693-39701
Environmental Science and Pollution Research - This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the... 相似文献
5.
Ghulam Muhiyuddin Kaloi Mehrunisa Memon Kazi Suleman Memon Sagheer Ahmad Saghir Ahmed Sheikh Ghulam Murtaza Jamro 《Environmental monitoring and assessment》2017,189(3):127
Spentwash is a rich source of organic matter and essential plant nutrients in addition to excess salts. Sugar mills in Pakistan discharge about 3.48 million tons of spentwash annually, with no proper procedures for its disposal or utilization. To test the effect of diluted spentwash on soil and the soil’s ability to support plant growth, sugarcane (Saccharum officinarum L.) variety CPF-237 was planted. The experiment was conducted in a randomized complete block design involving factorial combination of four concentrations of each spentwash (0, 10, 20, and 30%) and mineral fertilizers (0, 1/3, 2/3, and the full recommended rate of NP). The 10% spentwash plus 2/3 mineral fertilizer treatment substituted 33% each of N and P and 100% of K, saving mineral fertilizer cost (Rs. 48600 ~ US$458) in addition to 29.54% increase in yield over full NP fertilizer. The same treatment also improved the soil organic matter (65%), N (20%), P (25%), and K (230%) over full NP treatment alone. An increase in the salt content of the soil was detected within the prescribed limits, with the exception of HCO3. 相似文献
6.
Riaz Umair Murtaza Ghulam Saifullah Farooq Muhammad Aziz Humera Qadir Ayesha Abdul Mehdi Shahzada Munawar Qazi Muhammad Akram 《Environmental science and pollution research international》2020,27(32):39742-39752
Environmental Science and Pollution Research - In the developing world, rapid urbanization and industrialization produces an enormous volume of wastes daily. This study was aimed to explore the... 相似文献
7.
M. Qadir E. Quillérou V. Nangia G. Murtaza M. Singh R.J. Thomas P. Drechsel A.D. Noble 《Natural resources forum》2014,38(4):282-295
Food security concerns and the scarcity of new productive land have put productivity enhancement of degraded lands back on the political agenda. In such a context, salt‐affected lands are a valuable resource that cannot be neglected nor easily abandoned even with their lower crop yields, especially in areas where significant investments have already been made in irrigation and drainage infrastructure. A review of previous studies shows a very limited number of highly variable estimates of the costs of salt‐induced land degradation combined with methodological and contextual differences. Simple extrapolation suggests that the global annual cost of salt‐induced land degradation in irrigated areas could be US$ 27.3 billion because of lost crop production. We present selected case studies that highlight the potential for economic and environmental benefits of taking action to remediate salt‐affected lands. The findings indicate that it can be cost‐effective to invest in sustainable land management in countries confronting salt‐induced land degradation. Such investments in effective remediation of salt‐affected lands should form part of a broader strategy for food security and be defined in national action plans. This broader strategy is required to ensure the identification and effective removal of barriers to the adoption of sustainable land management, such as perverse subsidies. Whereas reversing salt‐induced land degradation would require several years, interim salinity management strategies could provide a pathway for effective remediation and further showcase the importance of reversing land degradation and the rewards of investing in sustainable land management. 相似文献
8.
Sadullah Mir Tariq Yasin Humaira Masood Siddiqi Ghulam Murtaza 《Journal of Polymers and the Environment》2017,25(4):1011-1020
In this study water soluble sodium carboxymethyl cellulose (CMC) was blended with high density polyethylene (HDPE) by peroxide-initiated melt compounding technique. The compatibility of the blended polymers were carried out by silane crosslinking agent. A series of blends were prepared by varying the CMC contents up to a maximum of 50 phr. The physical properties of non-crosslinked and crosslinked blends were investigated in detail. FTIR analysis of crosslinked blend confirmed the presence of Si–O–Si and Si–O–C absorption peaks at 1050 and 1159 cm?1. Thermal stability of crosslinked blends improved as compared to its non-crosslinked congener. Rheological study of crosslinked blends illustrated high complex viscosity and dynamic shear storage modulus. The tensile strength of virgin polyethylene was 8.1 MPa whereas the maximum tensile strength of 19.6 MPa was observed in crosslinked blend. Similarly lower deformation was observed in crosslinked blends under static load. Scanning electron microscopy of crosslinked formulations also showed strong adhesion between the polymers interface. The compatibility of HDPE and CMC is attributed to both free radical and condensation reactions. 相似文献
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10.
Manchar Lake is the largest natural freshwater lake in Pakistan. The Lake has received less fresh water in past few years.
In addition, drainage water is being discharged in the Lake through Main Nara Valley Drain (MNVD) since many years. Consequently,
concern has grown regarding the water quality of the Lake. The aim of this study was to assess the water quality of Manchar
Lake and MNVD and the objectives were to determine physiochemical properties and the concentrations of common cations and
anions as well as seven trace metals i.e. Cu, Ni, Zn, Co, Fe, Pb and Cd. The concentration of the trace metals were determined
by simultaneous preconcentration and solvent extraction using flame atomic absorption spectrometer. Results of physicochemical
parameters of Manchar Lake water samples showed mean pH 8.4 (±0.2), conductivity 2,310.3 (±581.3) μS cm−1 and hardness (as CaCO3) 213.1 (±62.3) mg l−1. Mean concentrations of cations and anions were Na 521.5 (±49.7), Cl− 413.6 (±225.7), Ca 70.7 (±12.9), Mg 56.2 (±28.9), K 17.6 (±6.5), 0.34 (±0.2) and 0.02 (±0.01) mg l−1. Mean concentrations of trace metals were Zn 15.7 (±1), Fe 12 (±3.5), Pb 9 (±2.7), Cu 8.9 (±7.7), Ni 4.3 (±3.4), Co 4 (±3.4)
and Cd 1.1 (±1) μg l−1. MNVD water samples showed mean pH 8.9 (±0.8), conductivity 1,735.7 (±567.8) μS cm−1 and hardness (as CaCO3) 184.8 (±32.4) mg l−1. In MNWD, the mean concentrations of cations and anions were Na 482.7 (±11.7), Cl− 395.7 (±271.5), Ca 79.1 (±23.5), Mg 54.2 (±28.1), K 26.2 (±21.3), NO−3 0.5 (±0.3) and 0.1 (±0.1) mg l−1. Mean concentrations of trace metals observed in MNWD water were Fe 14.9(±3.5), Cd 8.3 (±9.4), Pb 6.9 (±2.4), Cu 6.6 (±3.1),
Zn 6.2 (±1.8), Co 4.5 (±2.7), and Ni 3.5 (±2.9) μg l−1. The pH of both Manchar Lake and MNVD waters and concentration of Pb in Manchar Lake and concentration of Cd in MNVD water
were higher than the World Health Organisation’s guideline values for the drinking water quality. The water quality of Manchar
Lake was found degraded. 相似文献