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881.
Most developing countries, particularly Indonesia, will be facing problems of sludge pressure in the next decades due to the increase in practices of legal and illegal logging as well as land and water demands. Consequently, they will also be facing the challenges of soil erosion and sludge management due to increased quantities of sludge coming from several potential sources, such as activated sludge, chemical sludge, fecal sludge and solid wastes as well as erosion and sedimentation. Although the government of Indonesia has enacted laws and policies to speed up the implementation of the programs and activities related to sludge management, the detailed practice concepts in implementing the programs need to be identified. Discussion of role-sharing amongst the related government agencies, private institutions and other stakeholders is urgent for clarifying the participation of each party in the next years to come. This paper proposes a management approach and level of responsibilities in sludge management. Implementation of zero ΔQ, zero ΔS and zero ΔP policies needs to be adopted by local and central governments. Application of sludge on the agricultural lands and other uses will promote sustainable development.  相似文献   
882.
Concentration of radionuclides 210Pb and 7Be, having half lives of 22.3 years and 53.29 days, respectively, in the surface air samples of Islamabad (33.38° N, 73.10° E and Altitude ∼536 m asl.) are measured. The non-destructive technique of gamma-spectrometry, with a high purity germanium HPGe detector, was employed for the analysis of all samples. The annual average concentrations of 210Pb and 7Be in the surface air samples were determined as 0.284 ± 0.15 and 3.171 ± 1.14 mBq m−3, respectively. Our results have shown a seasonal variation of the concentration of 7Be in air samples with high values for the spring season. High concentrations for 210Pb are obtained when air masses originate from plain areas of Pothohar region, located in the South-West, West and North West of Islamabad. Our values of concentrations show a nice agreement with the relevant reported results.  相似文献   
883.
Ali N  Harrad S  Goosey E  Neels H  Covaci A 《Chemosphere》2011,83(10):1360-1365
Concentrations of several “novel” brominated flame retardants (NBFRs) are reported in indoor dust samples from Belgian houses (n = 39) and offices (n = 6) and from day-care centers and schools in the West Midlands of the UK (n = 36). Using a GC-ECNI/MS method, the following NBFRs were quantified: decabromodiphenyl ethane (DBDPE) (range <20-2470 ng g−1), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) (range <0.5-1740 ng g−1), tetrabromobisphenol A-bis(2,3-dibromopropylether) (TBBPA-DBPE) (range <20-9960 ng g−1), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) (range <2-436 ng g−1) and bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH) (range <2-6175 ng g−1). Hexachlorocyclopentadienyl-dibromocyclooctane (HCDBCO), another NBFR, was below the detection limit of 2 ng g−1 dust in all dust samples. No correlation was detected between concentrations of NBFRs and PBDEs. The ratio of TBB:TBPH in the dust samples ranged from 0.01 to 4.77 (average 0.42), compared to the ratio present in the commercial flame retardant product FM 550 (TBB:TBPH = 4:1). Furthermore, no correlation was detected between concentrations in dust of TBB and TBPH. This may suggest different sources of these NBFRs, or similar sources but compound-specific differences in their indoor fate and transport. Exposure via dust ingestion was estimated for both adults and toddlers under low-end (5th percentile), typical (median), and high-end (95th percentile concentrations) scenarios. These were calculated assuming 100% absorption of intake dust and using mean dust ingestion (adults = 20 mg d−1; for toddlers = 50 mg d−1) and high dust ingestion (adults = 50 mg d−1; for toddlers = 200 mg d−1). Typical exposure with high dust ingestion estimates for adults were 0.01, 0.2, 0.01, 0.02 and 0.08 ng kg−1 bw d−1 and for toddlers 0.05, 1.9, 0.08, 0.4 and 1.12 ng kg−1 bw d−1 for BTBPE, DBDPE, TBB, TBPH and TBBPA-DBPE, respectively. Our results showed that, similar to PBDEs, toddlers have higher exposure to NBFRs than adults. This study documents the presence of NBFRs in indoor environments, and emphasizes the need to evaluate the health implications of exposure to such chemicals.  相似文献   
884.
Hydrocarbon-utilizing microorganisms naturally associated with sawdust   总被引:1,自引:0,他引:1  
Ali N  Eliyas M  Al-Sarawi H  Radwan SS 《Chemosphere》2011,83(9):1268-1272
Sawdust, one of the materials used as sorbent for removing spilled oil from polluted environments was naturally colonized by hydrocarbon-utilizing fungi, 1 × 105-2 × 105 colony forming units (CFU) g−1, depending on the hydrocarbon substrate. This sorbent was initially free of hydrocarbon-utilizing bacteria. Incubating wet sawdust at 30 °C resulted in gradually increasing the fungal counts to reach after 6 months between 5 × 106 and 7 × 106 CFU g−1, and the appearance of hydrocarbon-utilizing bacteria in numbers between 8 × 104 and 3 × 105 cells g−1. The fungi belonged to the genera Candida (32% of the total), Penicillium (21%), Aspergillus (15%), Rhizopus (12%), Cladosporium (9%), Mucor (7%) and Fusarium (4%). Based on their 16S rRNA gene sequences the bacteria were affiliated to Actinobacterium sp. (38%), Micrococcus luteus (30%), Rhodococcus erythropolis, (19%) and Rhodococcus opacus (13%). Individual pure fungal and bacterial isolates grew on a wide range of individual pure aliphatic (n-alkanes with chain lengths between C9 and C40) and aromatic (benzene, biphenyl, anthracene, naphthalene and phenanthrene) hydrocarbons as sole sources of carbon and energy. Quantitative determinations revealed that all fungal and bacterial isolates could consume considerable proportions of crude oil, phenanthrene (an aromatic hydrocarbon) and n-hexadecane (an aliphatic hydrocarbon) in batch cultures. It was concluded that when sawdust is used as a sorbent, the associated microorganisms probably contribute to the bioremediation of oil and hydrocarbon pollutants in the environment.  相似文献   
885.
The in vitro degradation of fiber from two agricultural residues (Helianthus annuus and Zea mays) was studied using four saprophytic fungi. The changes in cellulolytic enzyme and phosphatase activities, the C/N ratio, the dry weight, the crude fiber (CF) content, and the protein and fiber digestibility coefficients were investigated in solid-state culture during a 45-day period of biodegradation. The FPase activity of Phanerochaete chrysosporium and the endoglucanase activities of P. chrysosporium and Trichoderma reesei compared to those of the other fungi were significantly (P < 0.05) high on both crop resides. Both acid and alkaline phosphatases were produced in greater amounts by P. chrysosporium than by the other fungi. The organic carbon contents of both residues were reduced more by T. reesei than by the other fungi. The fiber digestibility coefficient of untreated corn residue was higher than that of sunflower residue, but after treatment with fungi, the sunflower fiber digestibility increased more than that of corn did. Although the CF contents of both residues were decreased more by P. chrysosporium than by T. reesei, the fiber digestibility coefficients of both residues were increased more by T. reesei than by P. chrysosporium. The treatment of both crop residues increased their protein digestibility coefficients significantly compared to the control. The protein digestibility coefficients of both residues were increased more by T. reesei and P. chrysosporium than by the other fungi. In all treatments, the protein digestibility coefficient of sunflower residue was higher than that of corn residue.  相似文献   
886.
In this study, the applicability of physico-chemical methods was investigated for the pre-treatment of the olive mill effluents prior to the discharge into the common sewerage ending with a municipal wastewater treatment plant. The samples were taken from an olive oil industry operated as three-phase process located in Turkey. Various pre-treatment methods including acid craking, polyelectrolyte and lime additions were applied. Advanced oxidation study using Fenton's process was also investigated following pre-treatment by acid cracking and cationic polyelectrolyte. Acid cracking alone gave satisfactory treatment efficiencies and polyelectrolite additions to the acid-cracked samples enhanced treatment efficiency. Since a complete treatment plant is available at the end of the sewer system, results indicated that the effluents of the investigated industry could be discharged into the municipal sewerage in the case of total chemical oxygen demand (COD(tot)), suspended solid (SS) and volatile suspended solid (VSS) concentrations according to the Turkish Water Pollution Control Regulation after pre-treatment with 5 ppm anionic polyelectrolyte following acid cracking. The minimum COD(tot), SS and VSS removals were observed when raw wastewater was pre-treated with lime and the discharge standards to the municipal sewer system could not be met. Advanced oxidation with Fenton's process was applied after acid cracking and cationic polyelectrolyte treatment in order to investigate further reduction in chemical oxygen demand (COD) concentration for minimizing the influence of this industrial discharge on the existing municipal wastewater treatment plant. Results indicated that COD(tot) removal increased up to 89% from 74% after Fenton's oxidation for the acid cracked samples in which cationic polyelectrolite (10 ppm) was added.  相似文献   
887.
Tehran is one of the megacities of the world with a population of over eight million. Its air is highly polluted mainly due to the suspended particulate matters, which encompasses a wide spectrum of chemical elements. These elements based on their type, size, and impact on the life cycle have various environmental and heath risks. In this research, the neutron activation method is used to determine the concentration levels of Al, Ba, Fe, Mg, and V in the urban air. Thus, two districts of Tehran with different characteristics are selected. District 21 includes much of the industries located in Tehran metropolitan and is considered as an industrial area. In contrast, district 22 lacks any significant industrial activity. It is a newly established and expanding district adjacent to district 21 with a great deal of constructional activities. For the measurement of the suspended particulate matters in the air, the various sections of the aforesaid districts with industrial, residential, heavily congested traffic, residential/commercial, residential/heavily congested traffic, and residential/industrial classifications were identified. Subsequently, 24 sampling stations were selected. The sampling of the suspended particulate matters was conducted with the aid of a high volume pump containing 125 mm cellulose filters in two different time intervals. After completion of the sampling process, the samples were prepared and sent to the research reactor of the Iran Nuclear Energy Organization for Neutron Activation. During the next steps, the radiations emitted from the samples were registered, the radiation curves were plotted, and the amounts of the trace elements were determined. As a result, the average concentration levels of Al, Ba, Fe, Mg, and V were identified to be 3.301140, 2.273658 × 10, 4.0681696 × 10???1, 3.5525475 × 10???1, and 3.04075 × 10???2 μg/m3, respectively. Moreover, the emission sources of the aforesaid elements into the air were identified. The concentration levels of these elements in the industrial and heavily congested traffic sections were higher. Finally, it was concluded that the statistical analysis of these elements presents a meaningful correlation among them.  相似文献   
888.
Environmental monitoring and indoor radon measurement are important for public health, to estimate the cancer risk of respiratory system and, if necessary, to suggest proper methods that reduce indoor radon level. In this research, indoor radon concentration in the air has been measured in 150 apartments in Mashhad city. The result demonstrates about 94.7% of apartments have radon concentration less than 100 Bq/m3, taken by WHO as the action level, and 5.3% have the concentration higher than this level. As well as, annual radon dose has been assessed using the equation for annual effective dose calculation introduced by United Nations Scientific Committee on the Effects of Atomic Radiation.  相似文献   
889.
In order to assess the quality and suitability of waters in the Kor-Sivand river basin, 60 water samples from the Kor river and 90 water samples from wells in the basin were studied. Assessments were based on Piper's and Gibbs' diagrams for water quality, Food and Agricultural Organization's (FAO) guidelines, and US Salinity Laboratory diagram for water suitability. The results showed that the river water is of Ca-HCO(3) type, while well water is of Ca-Cl and Na-Cl type. Based on Gibbs' diagram, the source of soluble ions in the river water samples is the weathering of stones over which water flows, while evaporation was found to be the dominant process in the ion concentration of the well samples. According to the FAO Guidelines, the salinity of surface water for irrigation did not cause great restrictions; however, many of these waters could create potential permeability problems. In the groundwater samples, a high salt concentration is more important than the infiltration problem. Mg hazard values at some sites limit its use for agricultural purposes. One third of the river water samples and two thirds of well waters had more than 50% magnesium. Saturation indices showed that 94% of the analyzed water samples are supersaturated with calcite, aragonite, and dolomite. Based on the US Salinity Laboratory diagram, river water samples were classified as C(2)S(1) and C(3)S(1), while C(4)S(3), C(4)S(4), C(2)S(1), and C(3)S(1) were the most dominant classes in well samples. Some management practices necessary for sustainable development of water resources in the study area were discussed briefly, including appropriate selection of crops, adequate drainage, leaching, blending and cyclic use of saline water, proper irrigation method, and addition of soil amendment.  相似文献   
890.
In this work, spectrophotometer was used as a detector for the determination of uranium from water, biological, and ore samples with a flow injection system coupled with solid phase extraction. In order to promote the online preconcentration of uranium, a minicolumn packed with XAD-4 resin impregnated with nalidixic acid was utilized. The system operation was based on U(VI) ion retention at pH 6 in the minicolumn at flow rate of 15.2 mL min?1. The uranium complex was removed from the resin by 0.1 mol dm?3 HCl at flow rate of 3.2 mL min?1 and was mixed with arsenazo III solution (0.05 % solution in 0.1 mol dm?3 HCl, 3.2 mL min?1) and driven to flow through cell of spectrophotometer where its absorbance was measured at 651 nm. The influence of chemical (pH and HCl (as eluent and reagent medium) concentration) and flow (sample and eluent flow rate and preconcentration time) parameters that could affect the performance of the system as well as the possible interferents was investigated. At the optimum conditions for 60 s preconcentration time (15.2 mL of sample volume), the method presented a detection limit of 1.1 μg L?1, a relative standard deviation (RSD) of 0.8 % at 100 μg L?1, enrichment factor of 30, and a sample throughput of 42 h?1, whereas for 300 s of the preconcentration time (76 mL of sample volume), a detection limit of 0.22 μg L?1, a RSD of 1.32 % at 10 μg L?1, enrichment factor of 150, and a sampling frequency of 11 h?1 were reported.  相似文献   
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