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21.
The increasing amount of cyanided tailings produced as a by-product has gained significant attention in recent years because of the rapid development of the gold industry and extensive exploitation of gold mineral resources. The effective use of these secondary resources is becoming an important and urgent problem for all environmental protection staff. Manganese-catalyzed ozonation for the pre-oxidation of cyanided tailings was studied and the effects of Mn2+ dosage, initial sulfuric acid concentration, ozone volume flow, temperature and agitation speed on pretreatment were examined. The optimum reaction conditions were observed to be: ore pulp density 2.5%, agitation speed 700 r/min, temperature 60 ℃, Mn2+ dosage 40 g/L, ozone volume flow 80 L/hr, initial sulfuric acid concentration 1 mol/L, and reaction time 6 hr. Under these conditions, the leaching rate of Fe and weight loss could reach 94.85% and 48.89% respectively. The leaching process of cyanided tailings by Mn2+/O3 was analyzed, and it was found that the leaching of pyrite depends on synergetic oxidation by high-valent manganese and O3, in which the former played an important part. 相似文献
22.
Qureshi A Lo KV Mavinic DS Liao PH Koch F Kelly H 《Journal of environmental science and health. Part. B》2006,41(7):1221-1235
A combined approach of biological treatment, solids digestion and nutrient recovery was tested on dairy manure. A sequencing batch reactor (SBR) was operated in three modes, in order to optimize nutrient (nitrogen and phosphorus) removals. The highest average removal efficiencies of 91% for NH4-N, 59% for PO4-P and 80% for total chemical oxygen demand (COD) were achieved. Staining experiments suggested the coexistence of glycogen and phosphorus accumulating organisms. Anaerobic digestion of wasted bio-solids was able to produce a PO4-P concentration of 70 mgL-1 in the supernatant. A pilot-scale experiment, designed to recover phosphorus in the supernatant as struvite (magnesium ammonium phosphate), was able to remove 82% of soluble PO4-P. 相似文献
23.
Shahid Mahmood Baig Ayesha Azhar Hammad Hassan Jamshaid Mahmood Baig Muhammad Aslam Mohammad Amin Ud Din Javed Anver Qureshi Tariq Zaman 《黑龙江环境通报》2006,26(10):903-905
Pakistan has a large population of more than 150 million people with an overall carrier frequency of approximately 5.6% for β-thalassemia. Punjab is the largest province of the country having more than 50% of the population. The state of β-thalassemia is alarming as consanguinity is very high (>81%) and the literacy rate is low in South Punjab. A thalassemia prevention program is the need of the hour in this part of Pakistan. In this study, we initiated awareness, screening, and characterization of the mutations causing β-thalassemia as well as a genetic counseling program mainly in the districts of Faisalabad and D.G. Khan to establish prenatal diagnosis, a facility previously unavailable in this region for disease prevention. A total of 248 unrelated transfusion-dependent children and the available members of their families were screened to characterize the mutations and identify the carriers. Genetic counseling was provided to these families and prenatal diagnosis offered. In the samples analyzed, 11 β-thalassemia mutations and three hemoglobin variants were detected mainly by using the Monoplex and Multiplex ARMS-PCR. First-trimester prenatal diagnosis was carried out through chorionic villus sampling (CVS) in seven pregnancies at risk. As a result of our campaign, 145 carrier couples planning to have more children gave their consent to have retrospective prenatal diagnosis in every pregnancy in future. A cooperative trend and a positive attitude toward the prevention of β-thalassemia were noticed in the families with affected children and in the general population. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
24.
Ahamed Maqusood Akhtar Mohd Javed Khan Mohd Abdul Majeed Alhadlaq Hisham Abdulaziz 《Environmental science and pollution research international》2021,28(14):17109-17118
Environmental Science and Pollution Research - Recent attention has been focused on reproductive toxicity of nanoscale materials in combination with pre-existing environmental pollutants. Due to... 相似文献
25.
Jiang Yushi Khaskheli Asadullah Raza Syed Ali Qureshi Muhammad Asif Ahmed Maiyra 《Environmental science and pollution research international》2021,28(11):13323-13339
Environmental Science and Pollution Research - The study intends to explore the following objectives: initially, to examine the non-linear connection between globalization, renewable energy... 相似文献
26.
Kurramovich Khudoykulov Khurshid Abro Asif Ali Vaseer Arif I. Khan Saad Uddin Ali Syed Rashid Murshed Muntasir 《Environmental science and pollution research international》2022,29(23):34055-34074
Environmental Science and Pollution Research - Recently, the Japanese government has announced the national objective of turning the economy of Japan carbon–neutral by 2050. This... 相似文献
27.
Siddique Md Abu Bakar Islam Abu Reza Md Towfiqul Hossain Md Saddam Khan Rahat Akbor Md Ahedul Hasanuzzaman Md Sajid Md Wasiq Mamun Mia Md Younus Mallick Javed Rahman M. Safiur Rahman Md Mostafizur Bodrud-Doza Md 《Environmental science and pollution research international》2022,29(6):8577-8596
Environmental Science and Pollution Research - Currently, a well-developed combination of irrigation water quality index (IWQIs) and entropy water quality index (EWQIs) for surface water appraisal... 相似文献
28.
Nisar Asif Saeed Muhammad Muneer Majid Usman Muhammad Khan Iltaf 《Environmental science and pollution research international》2022,29(1):418-430
Environmental Science and Pollution Research - Photocatalytic treatment is one of the techniques used for the treatment of dyes-contaminated wastewater. It is important to develop an effective... 相似文献
29.
Felemban Bassem F. Essa Fadl Abdelmonem Afzal Asif Ahmed Mohamed Hamza Saleh Bahaa Panchal Hitesh Shanmugan Sengottiyan Elsheikh Ammar Omara Zakaria Mohamed 《Environmental science and pollution research international》2022,29(42):63248-63259
Environmental Science and Pollution Research - The shortage of potable water is a global problem. One of the techniques used to participate solving this problem is the solar distiller. The main... 相似文献
30.
Fresh and healthy specimens of Oreochromis niloticus (mean weight 70.5± 1.23 g and mean length, 12.3± 1.5cm) and Clarias gariepinus (mean weight, 41.8±2.3 g and mean length 13.78 ± 1.2 cm) were exposed to heavy metal lead, ranging in concentration from 10 to 18 mg L‐1 for O. niloticus and 20 to 28 mg L‐1 for C. gariepinus respectively. The 96 h LC50 for both the species was computed as 12.45 mg L‐1 (O. niloticus) and 22.65 mg L‐1 (C. gariepinus). The cichlid fish was exposed to sublethal concentration of lead (2, 4 and 6 mgL‐1) and catfish (4, 8 and 12 mgL‐1). The erythrocytes count, haemoglobin concentration, haematocrit and the value of serum glucose increased significantly (P < 0.01), whereas leucocytes count, serum protein and serum triglyceride after intoxication declined in both the species with the same pattern but in different quantity. After 96 h of time a significant depletion of muscle and liver glycogen was noted, being greater in muscle (16.7% in O. niloticus) and in liver (15.9% in C. gariepinus). The response of fish to lead was dose dependent. 相似文献