Upgraded modified forms of bituminous coal for the removal of safranin-T dye from aqueous solution

Natural bituminous coal was used as a precursor in the synthesis of different modified products. The modification of coal was performed by treating it with nitric acid (N-coal), coating its surface by zinc oxide nanoparticles (Z-coal), and converting it into porous graphite (PG). The effect of modification processes on the structures, morphologies, and optical properties was followed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectrum (FT-IR), and UV/VIS spectrophotometer analysis. The surface of N-coal grains becomes smoother than the surface of raw coal grains due to the removal of the associated impurities and the formation of nitrogen function groups. For Z-coal, the whole surface of coal grains appears to be completely covered by agglomerated ZnO nanoparticles of massive density and irregular shapes. The average crystallite size of the formed ZnO is ~22.2 nm and density of dislocations is 2.029 × 10^?3 dislocation/nm². Also, the removal of safranin-T dye by natural bituminous coal and its modified forms was investigated as a function of contact time, adsorbent mass, initial dye concentration, and pH value. At pH 8, the PG showed higher efficiency (96%) than Z-coal (93.5%), N-coal (74.5%), and natural coal (62%) after 2 h for 0.1 g on 100 mg/L dye. The obtained results are well fitted by pseudo-second-order kinetic than by intraparticle diffusion and Elovich kinetic models for the adsorption by N-coal, Z-coal, and PG, whereas the adsorption by raw coal is well fitted with both pseudo-second-order and Elovich kinetic models. The Langmuir isotherm model fits well the equilibrium adsorption isotherm of safranin by raw coal and its modified forms. The values of maximum adsorption capacity were calculated for raw coal, N-coal, Z-coal, and PG to be 21.3, 27.4, 32.46, and 33.67 mg/g, respectively. A monolayer model with one energy and a monolayer model with two energies as advanced equilibrium models were investigated for more physical interpretation of the adsorption process. The calculated parameters (number of adsorbed molecules per site and number of receptor sites per unit mass) reflected the role of modification processes in the adsorption behavior of safranin.

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Graphical abstract High volatile bituminous coal and its modified forms have been used for the removal of Safranin-T dye from aqueous solution.

     

Effects of Deltamethrin on striatum and hippocampus mitochondrial integrity and the protective role of Quercetin in rats

Environmental Science and Pollution Research - The present work is to evaluate the neurotoxicity induced by pyrethroid insecticide “Deltamethrin” at 0.32 mg/kg/day in two main...     

Performance evaluation of sequencing batch reactor for beverage industrial wastewater treatment

Attempts were made in this study to examine the effectiveness of sequencing batch reactor (SBR) for the treatment of beverage industrial wastewater. The SBR was operated at three different organic loading rates (OLRs): 2, 1.7 and 1.1 kg COD/m3 d. Results of continuous long-term operation showed that by decreasing OLR from 2 to 1.7 kg COD/m3 day, the removal efficiency was increased from 95.5 to 99.3% for COD, from 95.3 to 98.1% for BOD and from 87 to 97.7% for TSS. While further decreasing of the OLR to 1.1 kg COD/m3 day, there is no significant adverse effect on organics removal. Also, residual total nitrogen (TN) concentration decreased by decreasing the OLR. However, increasing the OLRs exerted a slightly negative effect on the removal of total phosphorous. On the other hand, the experimental data indicated that the substrate utilization kinetic followed Monod's kinetics model approximately. The maximum specific substrate utilization rate (micro(max), half velocity coefficient (Ks), growth yield coefficient (Y) and decay coefficient (Kd) were 2.94 d(-1), 15.22 mg/L, 0.2384 g VSS/g COD and 0.2019 h(-1), respectively.     

Evaluation of simulated strategies for reducing nitrate-nitrogen losses through subsurface drainage systems

The nitrates (NO(3)-N) lost through subsurface drainage in the Midwest often exceed concentrations that cause deleterious effects on the receiving streams and lead to hypoxic conditions in the northern Gulf of Mexico. The use of drainage and water quality models along with observed data analysis may provide new insight into the water and nutrient balance in drained agricultural lands and enable evaluation of appropriate measures for reducing NO(3)-N losses. DRAINMOD-NII, a carbon (C) and nitrogen (N) simulation model, was field tested for the high organic matter Drummer soil in Indiana and used to predict the effects of fertilizer application rate and drainage water management (DWM) on NO-N losses through subsurface drainage. The model was calibrated and validated for continuous corn (Zea mays L.) (CC) and corn-soybean [Glycine max (L.) Merr.] (CS) rotation treatments separately using 7 yr of drain flow and NO(3)-N concentration data. Among the treatments, the Nash-Sutcliffe efficiency of the monthly NO(3)-N loss predictions ranged from 0.30 to 0.86, and the percent error varied from -19 to 9%. The medians of the observed and predicted monthly NO(3)-N losses were not significantly different. When the fertilizer application rate was reduced ~20%, the predicted NO(3)-N losses in drain flow from the CC treatments was reduced 17% (95% confidence interval [CI], 11-25), while losses from the CS treatment were reduced by 10% (95% CI, 1-15). With DWM, the predicted average annual drain flow was reduced by about 56% (95% CI, 49-67), while the average annual NO(3)-N losses through drain flow were reduced by about 46% (95% CI, 32-57) for both tested crop rotations. However, the simulated NO(3)-N losses in surface runoff increased by about 3 to 4 kg ha(-1) with DWM. For the simulated conditions at the study site, implementing DWM along with reduced fertilizer application rates would be the best strategy to achieve the highest NO(3)-N loss reductions to surface water. The suggested best strategies would reduce the NO(3)-N losses to surface water by 38% (95% CI, 29-46) for the CC treatments and by 32% (95% CI, 23-40) for the CS treatments.     

Cytogenetic EffectsOf Hydrogen Fluoride TreatmentIn Tomato Plants

Seeds from tomato plants fumigated with hydrogen fluoride gas at a concentration of about 3 Mg/cu m were planted in pots in the greenhouse. A number of plants in each culture were found to be developing abnormally. These abnormalities consisted of one, three, or four cotyledons; deformed cotyledons; plumuless seedlings; fasciated petioles; wiry seedlings, double stalked plants; and dwarf seedlings. Such abnormal phenotypes were the same as, or similar to, known mutants. There was a trend toward a higher percentage of total phenotypic abnormalities with an increase in the treatment duration. Meiotic analyses of the Q. generation (offspring of the fumigated plants, Q) showed the occurrence of fragments or bridges plus fragments. There was also a trend toward a higher percentage of chromosomal aberrations with an increase in the treatment duration except for the 4 days duration which was higher than most of the other treatments. It is believed that the occurrence of these aberrations was due to crossing over in heterozygous paracentric inversions. These results suggest that HF is a mutagenic agent probably blocking directly or indirectly the replication of the DNA.     

Evaluation of the efficiency of monopolar and bipolar BDD electrodes for electrochemical oxidation of anthraquinone textile synthetic effluent for reuse

The efficiency of the electrochemical degradation of synthetic wastewater containing an anthraquinone dye has been comparatively studied in two electrolytic cells with a synthetic boron-doped diamond (Si/BDD) as an anode. The first is an individual cell (Cell 1) with monopolar electrode BDD and the second (Cell 2) has two bipolar electrodes BDD self-polarized. The bulk electrolysis was performed at the same initial operating conditions in order to quantify the influence of the initial pH and current density on dye discoloration and global mineralization removal. The current efficiency and the consumption energy were also evaluated. When the same solutions have been comparatively treated with the two cells, a quite good mineralization is found in Cell 2. This result supposed more fraction of the applied current is used for the electrocombustion reaction on Cell 2 if compared to Cell 1 and small amount rest for the side reaction of oxygen evolution. The HPLC analyses confirmed this hypothesis and showed that the concentration trend of intermediates (sulfanilic acid, phthalate acid and salicylic acid) with electrolysis time was different on two cells. Phototoxicity tests show that the electrochemical oxidation with BDD electrodes could be useful as a pretreatment technique for reducing hazardous wastewater toxicity.     

Determination of chlorinated pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers in human milk from Bizerte (Tunisia) in 2010

Thirty persistent organohalogen compounds including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in breast milk samples (n = 36) of primipara and multipara mothers from Bizerte in 2010. The analytical procedure involved the application of liquid-liquid extraction and gas chromatography with electron capture detector (GC-ECD) or mass spectrometry detector (GC-MS) for identification and quantification. Organohalogen compounds were found in all the analyzed samples, with predominance of p,p′-DDE, p,p′-DDT, p,p′-DDD, HCB and PCBs. The mean concentration of ∑DDTs in breast milk was 1163.9 ng g⁻¹ lipid wt. The ratio of p,p′-DDE/p,p′-DDT was low, suggesting that there is fresh intake of commercial DDT products in Bizerte. The mean levels of HCB and PCB were 286.8 and 331.2 ng g⁻¹ lipid wt respectively. These results were compared with the levels obtained in a previous study carried out in the same area in 2003. A general decrease of ∑DDTs levels and an increase of PCB levels were observed. Among the 10 PBDE congeners evaluated, BDE-28, BDE-47, BDE-99, BDE-66, BDE-138, BDE-100, BDE-154, BDE-153, and BDE-183 were detected in the analyzed samples at different frequency. The total PBDE concentrations ranged from 2.5 to 22.6 ng g⁻¹ lipid wt in the samples, with a mean and median value of 10.7 and 9.8 ng g⁻¹ lipid wt respectively. To our knowledge, this is the first data of PBDEs in Tunisian human milk. The present study shows that age and parity are factors influencing the levels of some organohalogen compounds in human milk.     

Air–dust-borne associations of phototrophic and hydrocarbon-utilizing microorganisms: promising consortia in volatile hydrocarbon bioremediation

Aquatic and terrestrial associations of phototrophic and heterotrophic microorganisms active in hydrocarbon bioremediation have been described earlier. The question arises: do similar consortia also occur in the atmosphere? Dust samples at the height of 15?m were collected from Kuwait City air, and analyzed microbiologically for phototrophic and heterotrophic hydrocarbon-utilizing microorganisms, which were subsequently characterized according to their 16S rRNA gene sequences. The hydrocarbon utilization potential of the heterotrophs alone, and in association with the phototrophic partners, was measured quantitatively. The chlorophyte Gloeotila sp. and the two cyanobacteria Nostoc commune and Leptolyngbya thermalis were found associated with dust, and (for comparison) the cynobacteria Leptolyngbya sp. and Acaryochloris sp. were isolated from coastal water. All phototrophic cultures harbored oil vapor-utilizing bacteria in the magnitude of 10⁵?g^?1. Each phototrophic culture had its unique oil-utilizing bacteria; however, the bacterial composition in Leptolyngbya cultures from air and water was similar. The hydrocarbon-utilizing bacteria were affiliated with Acinetobacter sp., Aeromonas caviae, Alcanivorax jadensis, Bacillus asahii, Bacillus pumilus, Marinobacter aquaeolei, Paenibacillus sp., and Stenotrophomonas maltophilia. The nonaxenic cultures, when used as inocula in batch cultures, attenuated crude oil in light and dark, and in the presence of antibiotics and absence of nitrogenous compounds. Aqueous and diethyl ether extracts from the phototrophic cultures enhanced the growth of the pertinent oil-utilizing bacteria in batch cultures, with oil vapor as a sole carbon source. It was concluded that the airborne microbial associations may be effective in bioremediating atmospheric hydrocarbon pollutants in situ. Like the aquatic and terrestrial habitats, the atmosphere contains dust-borne associations of phototrophic and heterotrophic hydrocarbon-utilizing bacteria that are active in hydrocarbon attenuation.     

Transcriptional profiles induced by the Aryl Hydrocarbon Receptor agonists 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran and 2,3,4,7,8-pentachlorodibenzofuran in primary rat hepatocytes

Toxicogenomics was used to examine mRNA expression profiles obtained from primary rat hepatocytes treated for 24 h with 0.01 or 1.0 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), 0.02 or 2.0 nM 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) and 0.1 or 10 nM 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF). The concentrations of 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF were chosen to be equivalent to 2,3,7,8-TCDD’s concentration based on the toxic equivalency factor/toxic equivalent (TEF/TEQ) method for estimating biological potency. 2,3,7,8-TCDD at 1.0 nM altered the expression of 533 genes; 2,3,4,7,8-PeCDF at 2.0 nM altered 182 genes, and 2,3,7,8-TCDF at 10 nM altered 154 genes. Of these, 57 genes were affected by all three congeners. Agglomerative hierarchical clustering revealed distinct congener-dependent gene subclusters. Principal components analyses of the microarray data revealed that these congeners cluster independently of one another. Data presented here demonstrate that equivalent TEQ concentrations of 2,3,7,8-TCDD, 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF, while altering the expression of a small battery of genes in common, also produce substantial congener specific alterations in gene expression.     

Overview of biomedical waste management in selected Governorates in Egypt: a pilot study

Inadequate management of biomedical waste can be associated with risks to healthcare workers, patients, communities and their environment. This study was conducted to assess the handling and treatment of biomedical waste in different healthcare settings in Egypt. Five hospitals and ten primary healthcare settings were surveyed using a modified survey questionnaire for waste management. This questionnaire was obtained from the World Health Organization (WHO), with the aim of assessing the processing systems for biomedical waste disposal. Researchers found that biomedical waste is inadequately processed in hospitals and primary healthcare settings due to the absence of written policies and protocols. Accordingly, healthcare staff, patients, the community and the environment may be negatively affected by exposure to the hazards of biomedical waste. The development of waste management policies, plans, and protocols are strongly recommended, in addition to establishing training programs on proper waste management for all healthcare workers.