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Mapping of Terrestrial Gamma Radiation in Soil Samples at Baghdad Governorate (Karakh Side), Using GIS Technology
2019
Ali Abid Abojassim and Leith Hani Rasheed
The radioactive field is one of the most important areas in human health. It must be studied to see the changes in the doses of human exposure. In this study, 46 soil samples were collected from different locations of Karakh side at Baghdad Governorate. The specific activity of natural radionuclides (terrestrial gamma radiation) 238U, 232Th and 40K for soil samples were measured using gamma-ray spectroscopy with NaI(Tl) ("3×3") detector in low-background. Moreover, ten radiological hazard parameters, which include radium equivalent activity (Raeq), absorbed gamma dose rate (Dγ), external hazard index (Hext), internal hazard index (Hint), representative gamma index (Iγr), annual effective dose equivalent (AEDE) that includes the indoor and outdoor effective dose rate, and ELCR were calculated. It has also used GIS technology for mapping specific activity and radiological radiation parameters for all the samples under study. The results show that, the average value of specific activity of terrestrial gamma radiation 238U, 232Th, 40K, 238U+232Th+40K and 235U were 16.47±0.94 Bq/ kg, 9.72±0.43 Bq/kg, 367.95±11.13 Bq/kg, 394.15±11.90 Bq/kg and 0.76±0.043 Bq/kg respectively. While, the average value of radiological radiation parameters such as Raeq, Hex, Hin, Iγr , Iα, Exposure, Dr, AGED, AEDEindoor, AEDEoutdoor, AEDEtotal, and ELCR in present study were 58.7183±2.017 Bq/kg, 0.1586±0.00546, 0.2032±0.00768, 0.4523±0.0151, 0.08237±0.0046, 3.367±0.113 μR/h, 28.8309±0.968 nGy/h, 207.1078±6.86 mSv/y, 0.1415±0.00475 mSv/y, 0.03541±0.00119 mSv/y, 0.177±0.00594 mSv/y and 0.6192 ±0.0208 respectively. The results indicate that the effective dose from terrestrial gamma radiation is everywhere across the area within the acceptable level, subject to the inherent spatial averaging of the measurements.
Mostrar más [+] Menos [-]Nano-porous Membrane Process for Brackish Groundwater Treatment: Efficiency Analysis Using Response Surface Methodology
2019
Yuzheng Lv, Jihao Zhou, Zhengjun Mai and Jie Liu
Excessively high concentration of inorganic salts in the groundwater is the main threat for residents to drink directly in the remote areas of northwestern China. In this paper, nano-porous membrane process was proposed to removal of diverse ions in such raw water. Through the response surface methodology (RSM), the effects of multiple factors on permeate flux and ion rejection rates were analysed, and the application scope of nanofiltration for various water resource was evaluated. It was found that the factors affecting permeate flux, chloride removal and nitrate removal (response value) followed some typical sequences, and the operating pressure was always the most influential factor. Besides, nanoporous membrane process showed predominant performance in the removal of sulphate, chloride and fluoride; the rejection rates were over 99%, 97% and 95%, respectively, and the produced water could completely satisfy the relevant national standards for drinking water. However, nitrate removal rate was seldom over 80%, and it reduced obviously with the increasing initial concentration of nitrate, thus the nitrate content of raw water should be controlled within 40 mg.L-1.
Mostrar más [+] Menos [-]Antibiotic Resistance of Pseudomonas aeruginosa in Well Waters in Irrigated Zone (Middle Atlas-Morocco)
2019
Fatima Zahra Hafiane, Latifa Tahri, Najia Ameur, Rajaa Rochdi, Karim Arifi and Mohammed Fekhaui
Pseudomonas aeruginosa is a bacteria which can live in freshwater, soil and plants. It is a commensal of the digestive tube, slightly abundant in human body. Its presence in wells water is a result of current anthropogenic activity and pollution loads. It is an important nosocomial pathogenic agent characterized by an intrinsic resistance to multiple antimicrobial agents which can develop high-level multidrug resistance. To assess the contamination of these well waters by this pathogenic germ, two hundred samples were collected for four seasonal campaigns between March 2017 and May 2018 with a rate of forty three (43) samples per season in an irrigated zone. The samples were analysed to identify P. aeruginosa, then the isolated serotypes were determined by slid agglutination test using four pools and 20 monovalent Antisera. The detected P. aeruginosa were tested for susceptibility to 18 antibiotics. A total of (n=85/139) isolated strains were identified as P. aeruginosa representing 61.15 % of prevalence among Pseudomonas spp. Antimicrobial resistance revealed that 68% of them are multidrug resistant, while15.09 % of strains resist at least to 7 antibiotics, 30.19% resist at least to 11 antibiotics, 13.21% resist at least to 12 antibiotics, 5.66% resist at least to 13 antibiotics, and 3.77% resist at least to 14 antibiotics. The high level resistance of P. aeruginosa is observed with piperacillin tazobactam (100/10μg) (84.91%), ciprofloxacin (5μg) (79.25%), imipenem (10μg) and ceftazidime (30μg) (37.58%). The resistance of phenotypes of P. aeruginosa strains allowed to identify (n=20/85) ESBL, (n=31/85) oxacillinase broad spectrum ES-OXA, (n=5/85) phenotype of impermeability to imipenem, (n=12/85) cephalosporinase AMPC, and (n=17/85) wild type. The results showed the high antibiotic resistance levels of P. aeruginosa strains from well water samples against antibiotics. Furthermore, based on the results, these well waters can be a source of P. aeruginosa and human and animal susceptibility to other opportunistic pathogens.
Mostrar más [+] Menos [-]Impact of Land Use Change on Hydrological Response of Krueng Aceh Watershed in Aceh Province, Indonesia
2019
Bos Ariadi Muis
Population growth and improvement in the people’s economy have caused the need for space to grow and have changed land use in the Krueng Aceh watershed. This study on the effect of changes in land use on the Krueng Aceh watershed hydrological response as a step to anticipate water shortage in the future using the geographical information analysis and the river regime coefficient (RRC) method approach. The results of this study revealed that the functional shifts from primary forests to production forests and from brushland to ricefield and settlements increased the RRC value from 14.59 to 56.74 in the last 20 years. The hydrological response showed that 18% of the water had the potential to not infiltrate and become runoff. The effect is a reduction in groundwater supply, flooding in the rainy season, drought in the dry season, and clean water scarcity in the future. The management of the future must be based on one river, one planning, and one management system principle.
Mostrar más [+] Menos [-]Structures and Anaerobic Metabolic Activity of Attached Microbial Communities During Biofilm Formation in Aquaculture Systems
2019
Jialei Li, Zhifei Li, Jun Xie, Guangjun Wang, Kai Zhang, Ermeng Yu, Wangbao Gong and Jingjing Tian
In this study, the structural characteristics of the attached microbial community during biofilm formation and the metabolic requirements under anaerobic conditions were evaluated. In particular, 16S rDNA sequencing technology was used to study the structural changes of the attached microbial community during biofilm formation (day 0, 10, 20, and 30) in an aquaculture system, and Biolog microplate technology was used to study metabolic characteristics under anaerobic conditions during biofilm formation. The AWCD (average well colour development), an indicator of carbon metabolism, of attached microorganisms during biofilm formation under anaerobic conditions differed significantly among time points (P < 0.05), and the carbon source utilization capacity was enhanced. Under anaerobic conditions during biofilm formation, the utilization of amines in six major carbon sources was the highest, followed by polymers, carbohydrates, amino acids, and carboxylic acids, and the utilization of phenols was the lowest. Under anaerobic conditions, the utilization rate by the attached microorganisms during biofilm formation was highest for Tween 40, followed by Tween 80, D-xylose, 4-hydroxybenzoic acid, α-D-glucose-1-phosphate, L-phenylalanine, and phenylethylamine. The 16s rDNA sequencing results showed that the dominant phyla of attached microorganisms during biofilm formation were mainly Proteobacteria, Bacteroidetes, Firmicutes, and Cyanobacteria. On the 10th and 20th days of biofilm formation, attached microorganisms were enriched for Rhodobacter of α-Proteobacteria and Janthinobacterium of β-Proteobacteria, which play important roles in biofilm denitrification. However, on the 30th day, enriched bacteria included the Burkholderiales of β-Proteobacteria, the Xanthomonadaceae and Thermomonas of γ- Proteobacteria, which function in cyanide decomposition.
Mostrar más [+] Menos [-]Environmental Pollution Caused by the Transportation Industry and Influencing Factors of Carbon Emission: A Case Study of Jiangxi Province, China
2019
Yating Huang
With the accelerating industrialization and urbanization in China, the energy consumption of the transportation industry in the country is increasing quickly, and its proportion to the total social energy consumption is significantly growing. The transportation industry is a main source of carbon emission in urban areas. The unreasonable structure of energy consumption, the low proportion of new-energy use, and low energy utilization influence the energy-saving and emission reduction in the transportation industry. Thus, in this work, the influencing factors of transportation-induced carbon emission were estimated to analyze the environmental pollution caused by the transportation industry further. Regression analysis was performed on the environmental pollution caused by the transportation industry and the influencing factors of carbon emission in Jiangxi Province, China. Subsequently, a random STIRPAT model was constructed, and the influencing factors of carbon emission from the transportation industry in Jiangxi Province from 2007 to 2017 were analyzed through the partial least squares (PLS) method. Regression results based on the PLS method were relatively ideal. Increases in gross domestic product per capita, population size, passenger person kilometers, rotation freight transport kilometers, and the number of car ownerships can intensify transportation-induced carbon emission. This emission is increased when transportation energy intensity declines, but can be significantly inhibited by increased energy prices. The conclusions of this study can provide references for the continuous optimization of the energy use structure in the transportation industry, saving of energy resources, reduction of greenhouse gas and pollutant emission, and acceleration of low carbonization in the transportation industry.
Mostrar más [+] Menos [-]Enzymatic Analysis and Effect of Vermicompost Production from Banana Leaves Waste Using Epigeic Earthworm Eudrillus euginea
2019
Jannathul Firdous, V. Bharathi, S. Durga Devi and J. Jayachitra
Recycling of organic waste with enormous nutrients gives soil fertility when added to the soil and reduce the usage of chemical fertilizers. Vermicomposting process of recycling the bio-organic waste by earthworms contains efficient nutrients with low levels of toxic contents. In the present study, banana leaves waste was mixed with cow dung in different ratios. The earthworm Eudrillus euginea was later added to the compost. Total organic matter (TOM), total organic carbon (TOC), pH, EC, total alkalinity and phosphorus were analysed and compared for different ratios of vermicompost at different day intervals. Microorganisms present in vermicompost were isolated and analysed for their enzymatic activities. Compost maturity was also observed by FTIR application. Results showed that the vermicompost quality was improved with positive catalase and protease enzymatic activity. FTIR analysis showed the proper maturation of vermicompost with reduced complex structures such as aromatic compounds, polysaccharides and polypeptides. It was concluded that composting of organic wastes by vermicomposting promote humification, increased microbial activity and enzyme production, which in turn increase the aggregate stability of soil particles resulting in better aeration with pollutionfree technique.
Mostrar más [+] Menos [-]Soil Organic Carbon and Silt-Clay Relationships in the Soil Orders of Northern Agriculture Region (NAR), Western Australia
2019
Ahmed Hasson, Abdulhussien Alaskary and Muhsin Jweeg
There are no recognized data about the relationships between soil organic carbon and soil texture in Northern Agriculture Region (NAR), Western Australia (WA). Such information is central in understanding the impact of silt and clay content of soil profile soil organic carbon. In order to describe mathematically this relation, twenty-one soil orders highly weathered soils (mostly sandy soils) in Northern Agricultural Region, Western Australia under similar climate, vegetation and topography were sampled at 120 cm depth and analyzed for texture and total SOC concentration. The SOC concentration was directly and linearly correlated with the combined clay + silt (but not to clay alone) content for all depths. The intercept and slope of these linear relations decreased with depth following exponential and logarithmic functions (P < 0.001, R2 = 0.81 and 0.76, respectively). These mathematical functions permitted the adjustment of the intercept and slope parameters of a SOC = a + b (clay + silt) function for any depth in the 0-120 cm interval. This profile pedotransfer function precisely estimated SOC concentration (P < 0.0001, R2 = 0.90) up to 120 cm of the studied soils. Using data from different soil orders, estimated vs. measured SOC relations with similarly high R2 values were obtained, despite slopes and intercepts were different than 1 and 0. This indicates that for the NAR, WA the textural control of SOC varies predictably with depth, and the proposed model can be calibrated to estimate SOC in subsurface layers of highly weathered soils.
Mostrar más [+] Menos [-]Natural Background Gamma Radiation Levels in the Environs of Proposed Petro-chemical Industry Near Jadcherla, Telangana State, India
2019
G. Srinivas Reddy, K. Vinay Kumar Reddy, B. Linga Reddy and B. Sreenivasa Reddy
A survey of environmental gamma radiation levels is attempted in the geographical site under construction to establish a petrochemical industry. The knowledge of natural background radiation is one of the significant steps in establishing the chemical industry. Some chemical operations such as chemical refinement may sometimes influence the natural radiation levels. The attempt of measurement of natural background gamma levels in the present paper is to establish the baseline data, which on further measurements will be useful to analyse the changes in natural background radiation levels at the time of operation of a chemical plant. The present investigation shows the activity levels of gamma radiation in the site under construction at 65 locations. The gamma levels are found to vary from 1459 μGyy-1 to 2765 μGyy-1 with the average of 2141±304 μGyy-1. It is to be noted from the study that the average gamma radiation levels at two sample locations, cement mixing point (2307 μGyy-1) and stone crushing point (2529 μGyy-1) have been elevated. The elevated radiation levels at the two sample locations can be attributed to the radioactive dust emitted in the process of crushing stones and cement mixing.
Mostrar más [+] Menos [-]High Rate Vermicomposting of Coral Vine by Employing Three Epigeic Earthworm Species
2019
S.G. Antony Godson and S. Gajalakshmi
Use of the high-rate vermicomposting system and its relevant technology were successfully applied to accomplish direct vermicomposting of coral vine leaves - devoid of any pre-treatment/composting or amended with cow dung as earlier proclaimed protocols for the vermicomposting of various phytomass had necessitated. Three earthworm species tested were Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, and they had shown efficient vermicast recovery with few instances of mortality and good reproduction over the 150-day experiment. In this duration, all vermireactors were run in semi-continuous mode at the solid retention time of 15 days. This process enabled us to improve process efficacy of the reactor by the required pointers and systematic process monitoring. This paper substantiates the potential of the high-rate vermicomposting system in direct and potential vermicomposting of coral vine without any pre-treatment/composting or cow dung amendments. The observations have significance for enhancing process economics and therefore, process utility.
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