127 research outputs found
The Effect of Organic Loading on Propylene Glycol Removal Using Fixed Bed Activated Sludge Hybrid Reactor
Propylene glycol is discharged to the surface and underground waters and vicinity soils via industrial wastewater effluents, posing many health and environmental risks. The main goal of this study was to remove propylene glycol from synthetic wastewater in a fixed bed activated sludge reactor. To observe the effects of organic loading on bioreactor performance, the organic loading was increased by two sequencing stages: first by hydraulic retention time (HRT) depletion and second via propylene glycol concentration increase. Propylene glycol removal efficiency in HRTs of 8, 6, 4 and
2 h was 95.86, 95.12, 93.96 and 79.08 % respectively. A constant HRT of 6 h was selected for the second stage; propylene glycol concentrations of 500, 1000, 1500, 2000 and 2500 mg L–1 were used. The removal efficiency for these concentrations was 95.12, 95.95, 88.54, 75.95 and 35.69 % respectively. Thus, the integrated fixed bed activated sludge reactor is an efficient, viable and promising technology for treating wastewaters containing propylene glycol
A Novel Integration of CWPO Process with Fe3O4@C and Sonication for Oxidative Degradation of 4-Chlorophenol
This current work deals with oxidative destruction of 4-chlorophenol (4-CP) with catalytic wet peroxide oxidation (CWPO) using Fe3O4@C and sonication (US) in aqueous solution. The Fe3O4@C catalyst was synthetized and characterized with Field Emission Electron Microscopy and X-Ray Diffraction. Effect of operational variables, including initial pH, catalyst dosage, H2O2 concentration, 4-CP concentration, and sonication were investigated. A removal efficiency of 99 % was obtained by the CWPO/US-Fe3O4@C process in selected conditions including pH 5, Fe3O4@C dosage of 0.8 g L–1, H2O2 concentration of 20 mM, sonication power of 300 W, and reaction time of 60 min. Results indicated significant 4-CP removal with CWPO/US-Fe3O4@C (99 %) compared to CWPO (67 %) and US (10 %). According to the results, Fe3O4@C nanocomposite can be considered a cost-effective catalyst since it demonstrated acceptable reusability performance in degradation of 4-CP by CWPO/US-Fe3O4@C process.
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Comparison of the Efficiency of Moving- and Fixed-bed Bioreactors for Treatment of High-strength Synthetic Wastewater
A lab-scale Plexiglas cubic container as a pre-aeration reactor with total volume of 10 L, and two integrated bioreactors including a moving-bed bioreactor (MBBR) and a fixed-bed bioreactor with total volume of 30 L separately were used for experimental study. The main purpose was to compare the performance of moving-bed
and fixed-bed reactors for degradation of high organic loading in synthetic wastewater. Varying organic loadings of 0.5 to 9 kg COD m3 d–1 were applied. Generally, the total microbial mass in terms of attached biofim and VSS was higher in the MBBR. The microbial mass in the MBBR increased from 4120 to 4640 mg L–1 and in the fixed-bed bioreactor from 4124 to 4564 mg L–1. The COD removal efficiency in sequencing runs of operation in moving-bed and fixed-bed bioreactors varied from 96.27 % to 81.27 %, and from 95.2 % to 74.82 % respectively. The data obtained from this study indicate that MBBR, with the applied media in this study, was more efficient than the fixed-bed bioreactor for biodegradation of organic matter under identical operating conditions
Distribution and health risk assessment of organochlorine pesticides in agricultural soils of the Aghili plain, Southwest Iran
Organochlorine pesticides (OCPs) are a well-known group of persistent man-made chemicals. In the present study, 55 agricultural soil samples were collected from the Aghili plain and analyzed for 20 OCPs with the aim of determining contamination profiles, spatial distribution, influencing factors and carcinogenic risks. Among different OCPs, only aldrin, dieldrin, 4,4-dichlorodiphenyldichloroethylene, and 4,4-dichlorodiphenyldichloroethane were detected. The other OCPs dosages were lower than the detection limit in all samples. The results of cancer risk assessment demonstrated no carcinogenic risks to an exposed population
Business process modelling and visualisation to support e-government decision making: Business/IS alignment
© 2017 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/978-3-319-57487-5_4.Alignment between business and information systems plays a vital role in the formation of dependent relationships between different departments in a government organization and the process of alignment can be improved by developing an information system (IS) according to the stakeholders’ expectations. However, establishing strong alignment in the context of the eGovernment environment can be difficult. It is widely accepted that business processes in the government environment plays a pivotal role in capturing the details of IS requirements. This paper presents a method of business process modelling through UML which can help to visualise and capture the IS requirements for the system development. A series of UML models have been developed and discussed. A case study on patient visits to a healthcare clinic in the context of eGovernment has been used to validate the models
A Novel Combination of Surfactant Addition and Persulfate-assisted Electrokinetic Oxidation for Remediation of Pyrene-Contaminated Soil
Effect of surfactant addition on persulfate-assisted electrokinetic remediation of pyrene-spiked soil was studied. The influence of effective factors including voltage, surfactant addition, moisture content, and persulfate concentration on the removal of initial pyrene concentration of 200 mg kg–1 were investigated. A complete pyrene removal was observed for voltage of 1 V cm–1, saturated conditions, Tween 80 concentration of 20 mL kg–1, and persulfate concentration of 100 mg kg–1 after 24 h, corresponding to pyrene mineralization of 61 %, based on TPH analysis. The experimental results were best fitted with pseudo-first-order kinetic model with correlation coefficient of 0.968 and rate constant of 0.191 min−1. The main intermediates of pyrene degradation were benzene o-toluic acid, acetic, azulene, naphthalene and decanoic acid. Finally, an unwashed hydrocarbon-
contaminated soil was subjected to persulfate-assisted electrokinetic
remediation, and a TPH removal of 38 % was observed for the initial TPH content of 912 mg kg–1, under the selected conditions.
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Surfactant-enhanced Bioremediation of n-Hexadecane-contaminated Soil Using Halo-tolerant Bacteria Paenibacillus glucanolyticus sp. Strain T7-AHV Isolated from Marine Environment
A halo-tolerant bacterial strain Paenibacillus glucanolyticus sp. strain T7-AHV isolated from marine environment was used for bioremediation of n-hexadecane-contaminated soil. Soil/water ratio, initial inoculums volume, surfactant addition, n-hexadecane concentration, and salinity were investigated. The possibility of biosurfactant production by isolated strain was also studied, and the results demonstrated that it was not a biosurfactant producer, based on measurement of the surface tension of culture broth. Both tween 80 and rhamnolipid enhanced the biodegradation of n-hexadecane significantly up to 44 and 46 %, respectively. A biodegradation rate of 39.7 % was observed at salinity level of up to 2 %, and the biodegradation efficiency decreased significantly at higher salinity concentrations. A natural hydrocarbon-contaminated soil sample with total petroleum hydrocarbon (TPH) concentration of 1437 mg kg–1 was subjected to bioremediation using the selected conditions of operational parameters, and a biodegradation rate of 22.1 % was obtained
The survey and identification source of white spot disease in shrimp Farm in Abadan area
In the summer of 2002 high mortality occurred in farm shrimp in Abadan area due to white spot disease. The main objective of this study was detection and identification the source of white spot syndrome virus. For this reason from 2004/11/4 until 2005/120/6 about 190 samples consisted of wild shrimp, crab, fish, and plankton collected and preserved in alcohol 90-75% for polymerase chain reaction (PCR).The samples transferred to the South Iranian Aquaculture Center in Ahwaz. The samples examined by commercial WSSV detection kit (Fast Target) and new kit design by Iranian Fisheries Research Organization (IFRO) and Biotechnology Research Center from Iran. The result from PCR showed the samples of Penaeus indicus brood stock and postlarvea, Parapenaeopsis stylifrus and Metapenaeus affinis was positive. The rest of samples did not show any sign of virus and they was negative by PCR. Because the disease outbreak occurred in 2002 and the samples collected in 2004, the situation of environmental in the area was changed and may be the virus disappears in the samples and died
Hypoxia-enhanced Blood-Brain Barrier Chip recapitulates human barrier function and shuttling of drugs and antibodies
The high selectivity of the human blood-brain barrier (BBB) restricts delivery of many pharmaceuticals and therapeutic antibodies to the central nervous system. Here, we describe an in vitro microfluidic organ-on-a-chip BBB model lined by induced pluripotent stem cell-derived human brain microvascular endothelium interfaced with primary human brain astrocytes and pericytes that recapitulates the high level of barrier function of the in vivo human BBB for at least one week in culture. The endothelium expresses high levels of tight junction proteins and functional efflux pumps, and it displays selective transcytosis of peptides and antibodies previously observed in vivo. Increased barrier functionality was accomplished using a developmentally-inspired induction protocol that includes a period of differentiation under hypoxic conditions. This enhanced BBB Chip may therefore represent a new in vitro tool for development and validation of delivery systems that transport drugs and therapeutic antibodies across the human BBB
Fish gene bank of the Persian Gulf and Oman Sea
Genetic studies and gene banks preparation can identify guidelines for improving diversity and population structure and estimation, poaching and also the amount of cross breeding and provide genetic classification. In this study, sampling was performed from the important studied species habitats areas for the species such as: Dasyatis bennetti، Netuma thalassina, Netuma bilineata Carcharhinus leucas، Choerodon robustus، Pseudorhombus pentophthalmus ،Pseudorhombus arsius Thunnus tonggol ،Euthynnus affinis and Trichiurus lepturus. Total DNA extraction was performed using phenol - chloroform method which is the most common method for DNA extraction in order to achieve high quality of DNA was performed in the preparation of gene bank in this study. After relevant studies on this gene primers were designed and in use. After editing the sequences, nucleotide BLAST (Basic Local Alignment Search Tool) was performed using NCBI blast main page. The sequences obtained from each sample were aligned and corrected from any ambiguities and assembled using Bio edit program .Trees were generated using maximum parsimony (MP), a character-based algorithm and neighbor joining (NJ) a distance-based algorithm for phenetic analysis. The distance matrix option of MEGA4 was used to calculate genetic distance according to the Kimura 2-parameter model of sequence evolution. Based on the results obtained, the optical density of 260 to 280 nm in the samples was recorded between 1/8 - 2, indicating good quality DNA samples. Optimized PCR reaction to 16SrRNA gene amplification using the gradient between 48 - 60° C showed that the most suitable criteria for binding primers, 54 to 58 Celsius degrees respectively. The project objectives including the identification of the genetic structure of the species, and draw the phylogenetic trees using two genes 16SrRNA, making identification and registration of specified computer storage and regulate the structure and management of mentioned species by focus on genetic resources 10 species of majour commercial and noncommercial fishes in the Persia Gulf and Oman Sea through the creation of an integrated network of aquatic genetic resources in the region to try to identify genetic resources and aquatic gene bank. This type of analysis could be considered as an important tool to be used in broodstock selection in breeding programs. Also identify the species of fish named as Pseudorhombus pentophthalmus with a new haplotype and genetic differences 7% in compare to the samples recorded in the World gene Bank can considered as a major achievements of this research
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