133 research outputs found
Application of chitin derivatives for removal of radionuclides from radioactive effluent
In this study shrimp shell waste and their derivatives Chitin and Chitosan were studied for 60Co, 137Cs, 90Sr and 54Mn adsorption from low-level radioactive liquid waste (LLW) in batch and 137 continuous method. Shrimp shell waste, demineralized shrimp shell waste, Chitin and Chitosan were selected as natural organic adsorbent. The batch and column ion exchange experimental results show that the sorption was depended on pH, particle size, adsorbent type, deacetylation factor and treating tine. Temperature changes have an effect on treating time but no effect on total sorption. Chitin derivatives, particularly chitosan I & 2, are efficient for radioisotopes removal. Chitosan I with 50-70% deacetylation factor has the best aptitude for removal of radioisotopes and the shrimp shell has the worse
Phytoremediation of Soils Contaminated with Heavy Metals Resulting from Acidic Sludge of Eshtehard Industrial Town using Native Pasture Plants
Phytoremediation of heavy metals is considered as an inexpensive and practical technique for purifying contaminated soil, especially when eco-friendly native pasture plants of the contaminated area are used. In this study, heavy metals in soil including Cr, Zn, Cd, Pb, and Ni and native pasture plants around Eshtehard industrial town, which were contaminated due to the entry of acidic sludge, were examined. In this regard, the hyperaccumulation and phytostabilization potential of the plants in the study area were investigated. Accordingly, A.tenuifolia in Cd, Pb and Ni, C.persica in Zn, C. arenarius in Ni, P. piptostigma in Cr and Zn, B. tectorum in Cd and Zn, S. hohenackeriana in Cr, Pb and Cd, P.aucheri in Zn, and P. harmala L in Pb and Ni. Species with stabilizing potential include A. tenuifolia In Cd and Ni, N. persica in Zn, A.tauschii and B. tectorum in Ni, P.aucheri and P.harmala in Pb. Hyperaccumulating plants can be disposed of easily just like industrial wastes with heavy metals. Plants with stabilizing capacity can prevent the spread of heavy metal contamination to uncontaminated areas like the surrounding farms in addition to providing visual beauty for the region. Keywords: acidic sludge, heavy metals, phytoremediation, Eshtehard industrial tow
Phytoremediation of Soils Contaminated with Heavy Metals Resulting from Acidic Sludge of Eshtehard Industrial Town using Native Pasture Plants
Phytoremediation of heavy metals is considered as an inexpensive and practical technique for purifying contaminated soil, especially when eco-friendly native pasture plants of the contaminated area are used. In this study, heavy metals in soil including Cr, Zn, Cd, Pb, and Ni and native pasture plants around Eshtehard industrial town, which were contaminated due to the entry of acidic sludge, were examined. In this regard, the hyperaccumulation and phytostabilization potential of the plants in the study area were investigated. Accordingly, A.tenuifolia in Cd, Pb and Ni, C.persica in Zn, C. arenarius in Ni, P. piptostigma in Cr and Zn, B. tectorum in Cd and Zn, S. hohenackeriana in Cr, Pb and Cd, P.aucheri in Zn, and P. harmala L in Pb and Ni. Species with stabilizing potential include A. tenuifolia In Cd and Ni, N. persica in Zn, A.tauschii and B. tectorum in Ni, P.aucheri and P.harmala in Pb. Hyperaccumulating plants can be disposed of easily just like industrial wastes with heavy metals. Plants with stabilizing capacity can prevent the spread of heavy metal contamination to uncontaminated areas like the surrounding farms in addition to providing visual beauty for the region. Keywords: acidic sludge, heavy metals, phytoremediation, Eshtehard industrial town
Ensemble Classification and Extended Feature Selection for Credit Card Fraud Detection
Due to the rise of technology, the possibility of fraud in different areas such as banking has been increased. Credit card fraud is a crucial problem in banking and its danger is over increasing. This paper proposes an advanced data mining method, considering both feature selection and decision cost for accuracy enhancement of credit card fraud detection. After selecting the best and most effective features, using an extended wrapper method, ensemble classification is performed. The extended feature selection approach includes a prior feature filtering and a wrapper approach using C4.5 decision tree. Ensemble classification, using cost sensitive decision trees is performed in a decision forest framework. A locally gathered fraud detection dataset is used to estimate the proposed method. The proposed method is assessed using accuracy, recall, and F-measure as evaluation metrics and compared with basic classification algorithms including ID3, J48, NaĂŻve Bayes, Bayesian Network and NB tree. Experiments show that considering the F-measure as evaluation metric, the proposed approach yields 1.8 to 2.4 percent performance improvement compared to other classifiers
SMOKE AND VAPOR PLUME MERGENCE
Observations at power plants have indicated that vapor plumes emitted from cooling
towers frequently merge with smoke plumes released from stacks. Mergence of cooling tower
and stack plume leads to formation of acidic compounds which have adverse effects on the en-
vironment. Wind speed and direction play an important role in merging smoke and vapor
plume. This paper lists some arguments to verify that studies have not sufficiently addressed
stack and cooling tower plume mergence. In conclusion, the present authors hope to find more
information in the future with regard to vapor and smoke plume mergence
The effect of salts on the liquid–liquid phase equilibria of PEG600 + salt aqueous two-phase systems
Six new ATPSs were prepared by combining polyethylene glycol PEG600 with potassium citrate, dipotassium hydrogen phosphate, sodium formate, potassium formate, sodium sulfate, and lithium sulfate. Complete phase diagrams, including the binodal curve and three tie-lines, were determined at 23 °C. The experimental data obtained for the binodal curve were successfully adjusted to the Merchuk equation, and the reliability of tie-line data was confirmed using the equations suggested by Othmer–Tobias and Bancroft. The ability of each ion to induce ATPS formation was investigated. Na+ proved to be more effective in ATPS formation than K+ and Li+. For potassium salts, the order observed for the effectiveness of the anions was: HPO42– > C6H5O73– > HCO2–. Regarding the sodium salts, it was found that SO42– is clearly more effective than HCO2–. The position of the ions in the Hofmeister series and their free energy of hydration (ΔGhyd) were used to explain the ability of the ions to induce PEG salting-out. Furthermore, the effective excluded volume (EEV) of the salts was determined and the following order was found: Na2SO4 > K2HPO4 > Li2SO4 > K3C6H5O7 > NaCHO2 > KCHO2. Similar order was obtained when analyzing the size of the heterogeneous regions, suggesting the practical use of EEV as a comparison parameter between different ATPSs.This work is partially supported by project PEst-C/EQB/LA0020/2011, financed by FEDER through COMPETE-Programa Operacional Factores de Competitividade and by FCT-Fundacao para a Ciencia e a Tecnologia. Sara Silverio acknowledges her Ph.D. grant from FCT (SFRH/BD/43439/2008)
Evaluation of Anion Influence on the Formation and Extraction Capacity of Ionic-Liquid-Based Aqueous Biphasic Systems
Application of Chitin derivatives for removal of radionuclides from radioactive effluent
In this study shrimp shell waste and their derivatives Chitin and Chitosan were studied for 60Co, 137Cs, 90Sr and 54Mn adsorption from low-level radioactive liquid waste (LLW) in batch and 137 continuous method. Shrimp shell waste, demineralized shrimp shell waste, Chitin and Chitosan were selected as natural organic adsorbent. The batch and column ion exchange experimental results show that the sorption was depended on pH, particle size, adsorbent type, deacetylation factor and treating tine. Temperature changes have an effect on treating time but no effect on total sorption. Chitin derivatives, particularly chitosan I & 2, are efficient for radioisotopes removal. Chitosan I with 50-70% deacetylation factor has the best aptitude for removal of radioisotopes and the shrimp shell has the worse.....
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