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The degradation of BPA on enhanced heterogeneous photo-Fenton system using EDDS and different nanosized hematite Texte intégral
2020
Feng, Xiaoqing | Luo, Mengqi | Huang, Wenyu | Huang, Ying | Xie, Hongjie | Xu, Zisong | Zhang, Jian | Luo, Wei | Wang, Shuangfei | Lin, Hongfei
Photo-Fenton processes have been widely studied in wastewater treatment. In this research, the degradation of bisphenol A (BPA) was carried out in a new heterogeneous photo-Fenton process. The ethylenediamine-N,N′-disuccinic acid (EDDS) was used as chelating agent in this system with two different kinds of commercially available nanosized hematite (30 nm and 80 nm) addition. The results showed that the present of EDDS could enhance the degradation efficiency. And can be concluded that the degradation efficiency is better in the system with 30 nm hematite. The TEM, XRD, and specific surface area were conducted to understand the different characteristics of the two size hematite. The adsorption experiments of BPA and EDDS on hematite proved that there was little adsorption of BPA while the EDDS was adsorbed much more on hematite, which has confirmed Fe(III) and EDDS can form Fe(III)-EDDS complex. The effects of different parameters including hematite loading, H₂O₂, and EDDS concentrations on the degradation process were investigated. According to the results, the optimum condition for BPA degradation using 30 nm (0.8 g L⁻¹ hematite, 0.1 mmol L⁻¹ H₂O₂, and 1.2 mmol L⁻¹ EDDS) and 80 nm (0.6 g L⁻¹ hematite, 0.05 mmol L⁻¹ H₂O₂, and 1.2 mmol L⁻¹ EDDS) hematite were selected. It was confirmed that the ·OH plays an important role in the oxidation process through attacking the BPA molecule and produce hydroxyl addition derivative. In addition, O₂ can react with electron (e⁻) and holes (h⁺) produced by iron oxide under UV irradiation to create ¹O₂, which could work as potential reactive species to oxidize BPA.
Afficher plus [+] Moins [-]Polymorphism of glutathione S-transferase in the population of Polish patients with carcinoma of the prostate Texte intégral
2020
Drozdz-Afelt, Joanna M. | Koim-Puchowska, Beata | Kłosowski, Grzegorz | Kamiński, Piotr
The aim of the study was frequency analysis of GSTM1, GSTT1, and GSTP1 polymorphisms of glutathione S-transferase in the group of patients with prostate cancer and in a control group of healthy individuals. Genomic DNA was isolated; molecular analysis of glutathione S-transferase M1 and T2 polymorphisms was performed using multiplex PCR and RFLP methods. The products of the PCR reaction were then visualized in agarose gel, and a statistical analysis of the results was performed. No statistically significant differences were found in the frequency of glutathione S-transferase polymorphisms between 66 patients with prostate cancer and the control group (64 healthy volunteers). The GSTM1 gene deletion was found in ca. 47% of patients with prostate cancer and in ca. 55% of the controls. The GSTT1 deletion was found in approximately 17% of patients and 14% of the controls. The distribution of GSTP1 Ile/Ile, Ile/Val, and Val/Val polymorphisms was ca. 51.5%, 39%, and 9% in the group of patients and 61%, 34%, and 5% in the control group, respectively. The results indicate that there is no relationship between glutathione S-transferase polymorphisms and prostate cancer in the study group, which is a novelty when compared with the previous work on the role of these genetic variants in the etiology of cancer.
Afficher plus [+] Moins [-]Microemulsion-mediated preparation of Ce2(MoO4)3 nanoparticles for photocatalytic degradation of crystal violet in aqueous solution Texte intégral
2020
Dargahi, Maryam | Masteri-Farahani, Majid | Shahsavarifar, Samaneh | Feizi, Marzieh
Preparation of Ce₂(MoO₄)₃ nanoparticles is reported via the microemulsion method by using two different surfactants, i.e., cationic surfactant, cetyltrimethylammonium bromide (CTAB), and nonionic surfactant, Triton X-100. The water pools produced in the microemulsion systems behave as nanoreactors for reaction of the cerium (3+) and molybdate ions to produce Ce₂(MoO₄)₃ nanoparticles. The structure and morphology of the products were characterized by using Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray analysis (EDX), UV-Vis spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA-DTA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The prepared Ce₂(MoO₄)₃ nanoparticles were successfully utilized as photocatalysts to remove crystal violet from aqueous solution in which the maximum percentage of dye degradation was about 89% after 5 h under the visible light irradiation. Also, kinetic study of the photocatalytic degradation revealed that pseudo-second order model is the best one for describing kinetic of the reaction.
Afficher plus [+] Moins [-]Evaluation of bone marrow hemopoiesis and the elemental status of the red bone marrow of chickens under introduction of copper to the organism Texte intégral
2020
Vishnyakov, Alexandr | Udavliev, Damir | Timofeev, Dmitriy | Kvan, Olga
The role of chemical elements in an organism is versatile and multifunctional. However, you should pay attention to the reaction of the organism on the introduction of chemical elements with different biological roles, which is predetermined by the physiological role of organs and body systems. These include the red bone marrow, which primarily responds to endogenous and exogenous factors by its functional significance. Analyzing the myelogram of birds after the various ways of copper NP introduction into the body and the different dosages, we found that, by the end of the experiment, the total numbers of bone marrow cells in all groups were lower than the initial values: in the second group—12.54% lower (p < 0.05), in third—26.32% lower (p < 0.001), for the fourth—14.75% lower (p < 0.05), with exception for the first experimental group where this index was 45.51% higher (р < 0.001). We revealed the following changes in the peripheral blood: the hemoglobin content by the end of the experiment was significantly higher than the initial values: by 18.63% for the first group (p < 0.01); 28.61% higher in the third group (p < 0.001); and 15.76% higher for the fourth (p < 0.01), except the animals of the second group (3.23% lower). The concentration of erythrocytes in all groups was higher than that of the background: by 24.56% (p < 0.001), by 3.37%, by 26.18% (p < 0.001), and by 14.85% (p < 0.01), respectively; the leukocyte concentration in the first group was 39.63% higher (p < 0.001), it remained at the level of the initial values in the other groups. The erythrocyte sedimentation rate in all groups increased by 2.4, 4.0, 2.01, and 1.86 times (p < 0.001), respectively. We revealed that the introduction of copper into an organism in the form of nanopowder both with feed and intramuscularly significantly caused an increase of the content of such elements as arsenic, copper, and silicon and a decrease of calcium, potassium, magnesium, phosphorus, boron, cobalt, iodine, lithium, sodium, zinc, tin, and strontium in the marrowy aspirate. Moreover, compared with the first group (p < 0.01), increasing doses of nanopowders caused a significant rise in the arsenic and tin concentrations and a decline of iodine and strontium. We found that copper nanoparticles ambiguously affect the bone marrow hemopoiesis of poultry; increasing the dose and changing the type of introduction activating the bone marrow hematopoietic function, in particular, granulocyto-, megakaryocyto-, and erythropoiesis.
Afficher plus [+] Moins [-]Spent mushroom substrate combined with alkaline amendment passivates cadmium and improves soil property Texte intégral
2020
Jin, Zonghui | Zhang, Meng | Li, Rui | Zhang, Xu | Wang, Guoliang | Liu, Xuesheng | Qu, Juanjuan | Jin, Yu
As an extremely toxic metal, cadmium (Cd) is readily taken up by most plants. In situ Cd passivation is of great importance to reduce Cd availability in soil. In this experiment, two alkaline amendments, lime (L) (at a dosage of 0.02%, 0.04%, or 0.08%) and biochar (B) (at a dosage of 0.5%, 1%, or 2%), were used to improve Cd passivation by spent mushroom substrate (SMS) in a simulating Cd-contaminated soil (0.6 mg kg⁻¹). Results showed that the application of SMS alone reduced Cd bioavailability by 44.80% and EC by 9.71% and increased soil pH by 0.61 units, CEC by 25.32%, and soil enzymes activities by 17.11% to 21.10% compared with non-amendment Cd-contaminated soil. Biochar combination enhanced the efficiency of SMS on Cd reduction by 48.32–66.58% and pH increased by 0.17 to 0.59 units and enzymes activities elevation by 5.74% to 47.29% in a dose-dependent manner. Lime also facilitated SMS to passivate Cd by decreasing bioavailable Cd by 63.10%–66.47% and increasing soil pH by 0.25–0.72 units and enzymes activities by 3.28% to 37.86% compared to those of SMS. Among six combined amendments, SMSB3 (0.5% SMS + 2% B) performed best in reducing bioavailable Cd (39.46% higher than SMS), increasing organic matter content (28.54% higher than SMS) and soil enzyme activities (25.82%, 47.29%, and 26.23% higher than that of SMS for catalase, urease, and invertase, respectively). Both biochar and lime can assist SMS to passivate Cd and improve soil property, and biochar is more efficient than lime in reducing cadmium content and increasing enzyme activity and organic matter.
Afficher plus [+] Moins [-]A simple magnetic solid-phase extraction method based on magnetite/graphene oxide nanocomposite for pre-concentration and determination of melamine by high-performance liquid chromatography Texte intégral
2020
Abdolmohammad-Zadeh, Hossein | Zamani, Abbasali | Shamsi, Zahra
In this study, a clean and simple magnetic solid-phase extraction (MSPE) procedure using magnetite/graphene oxide nanocomposite as an adsorbent was developed for melamine separation and preconcentration from water and dairy products. After synthesis and characterization of the adsorbent, adsorption isotherms and kinetic studies of the adsorption were carried out. The analyte quantification was performed by reversed phase high-performance liquid chromatography after elution of the preconcentrated analytes from the adsorbent surface. Several factors affecting the extraction/preconcentration procedure such as pH, adsorbent amount, extraction time, sample volume, type, and volume of eluent were investigated. The optimizing of some important parameters was assessed by employing a response surface method. The constructed calibration curve in the optimized conditions is linear in the working range of 0.10–100 μg L⁻¹ with a correlation coefficient of 0.9999. The detection limit, limit of quantification, and enrichment factor are 0.03 μg L⁻¹, 0.10 μg L⁻¹, and 500, respectively. The melamine relative recoveries from different real samples are between 97.20 and 103.10% with relative standard deviations of 1.07–4.98%.
Afficher plus [+] Moins [-]Cadmium and chromium levels in water and edible herbs in a risk assessment study of rural residents living in Eastern Iran Texte intégral
2020
Sayadi, Mohammad Hossein | Kharkan, Javad | Binkowski, Lukasz J. | Moshgani, Mahmoud | Błaszczyk, Martyna | Mansouri, Borhan
In arid and semi-arid regions of Iran, water is supplied by qanats, underground channels where pollution is suspected, but unestablished. The aim of this study was thus to run a risk assessment study regarding the levels of cadmium (Cd) and chromium (Cr) in qanat water and edible herbs (Adiantum capillus-verenis, Chara globularis and Plantago lanceolata) growing in qanats in 14 villages in South Khorasan Province in Iran between April and August 2018. Samples were collected in qanats from the same sampling points, and after mineralization in nitric and perchloric acids were analyzed for metal concentrations by means of atomic absorption spectrometry. Concentrations of Cd and Cr found in water were not high (0.028 and 1.091 μg L⁻¹, respectively) and contamination parameters revealed no pollution. The ingestion rate of water and the exposure frequency to metals were the most relevant variables in the model of a sensitivity analysis, but the Hazard Quotient indicated no risk of non-carcinogenic health problems to consumers of the water. The Carcinogenic Risk parameter suggested, however, that there is a risk of these consumers’ developing cancer. Concentrations found in herbs were higher than in water but remained below permissible thresholds. Hazard Quotient values of three species studied in the case of children and A. capillus-verenis in the case of adults indicated a potential non-carcinogenic health risk linked with eating them. The study reveals that further research to include many of the qanats across Iran should be carried out to verify the scale of the risk suggested. Graphical abstract
Afficher plus [+] Moins [-]TiO2 nanoparticles potentiated the cytotoxicity, oxidative stress and apoptosis response of cadmium in two different human cells Texte intégral
2020
Ahamed, Maqusood | Akhtar, Mohd Javed | Alaizeri, ZabnAllah M. | Alhadlaq, Hisham A.
Widespread application of titanium dioxide nanoparticles (nTiO₂) and ubiquitous cadmium (Cd) pollution may increase their chance of co-existence in the natural environment. Toxicological information on co-exposure of nTiO₂ and Cd in mammalian models is largely lacking. Hence, we studied the combined effects of nTiO₂ and Cd in human liver (HepG2) and breast cancer (MCF-7) cells. We observed that nTiO₂ did not produce toxicity to HepG2 and MCF-7 cells. However, moderate concentration of Cd exposure caused cytotoxicity to both cells. Interestingly, non-cytotoxic concentration of nTiO₂ effectively enhanced the oxidative stress response of Cd indicated by pro-oxidants generation (reactive oxygen species, hydrogen peroxide, and lipid peroxidation) and antioxidants depletion (glutathione level and glutathione reductase, superoxide dismutase, and catalase enzymes). Moreover, nTiO₂ potentiated the Cd-induced apoptosis in both cells suggested by altered expression of p53, bax, and bcl-2 genes along with low mitochondrial membrane potential. Cellular uptake results demonstrated that nTiO₂ facilitates the internalization of Cd into the cells. Overall, this study demonstrated that non-cytotoxic concentration of nTiO₂ enhanced the toxicological potential of Cd in human cells. Therefore, more attention should be paid on the combine effects of nTiO₂ and Cd on human health.
Afficher plus [+] Moins [-]Prediction of water inflow from fault by particle swarm optimization-based modified grey models Texte intégral
2020
Ma, Dan | Duan, Hongyu | Li, Wenxuan | Zhang, Jixiong | Liu, Weitao | Zhou, Zilong
Water inflow from fault (WIF) and its secondary impacts are the main environmental challenges in the mining industry. Traditional prediction methods for WIF are exceedingly challenging and costly. In this article, two exponentially weighted moving average (EWMA) modified grey models (GMs, i.e., EGM and REGM) were established to predict the WIF. Particle swarm optimization (PSO) algorithm was employed to optimize parameters of the models. Based on actual WIF data from Buliangou coal mine, the optimized models (i.e., EGM-PSO, REGM-PSO) were used to obtain the prediction equations for WIF. To investigate the validity of the proposed models, the differences between actual values and predicted values were analyzed, and comparison results were obtained by the commonly used GM and GM-PSO. Results show that, for the sample with the larger initial particle swarm and smaller inertia weight, there is a faster convergence speed of the PSO algorithm. Particle search efficiency in the PSO-optimized EWMA-GM is higher than that in the GM-PSO. Through the predicted results of WIF, it is found that the REGM-PSO is the best choice for WIF prediction, and the more historical information, the higher the predicted accuracy. Besides, the parameter optimization by the PSO, the EWMA optimization method and optimization of residuals all can improve the predicted accuracy. Predicted results also show that WIF will have a substantial growth in the future. Therefore, reasonable measures (e.g., draining and grouting) need to be taken to mitigate the damage caused by fault water inflow.
Afficher plus [+] Moins [-]Garbage in garbage out: the contribution of our industrial advancement to wastewater degeneration Texte intégral
2020
Unuofin, John O.
Natural water sources are habitually marred by insidious anthropogenic practices and municipal wastewater discharges that contain either of xenobiotic pollutants and their sometimes more toxic degradation products, or both. Although wastewater is considered as both a resource and a problem, as explained in this review, it is however daunting that, while the global village is still struggling to decipher the mode of proper handling, subsequent discharge and regulation of already established aromatic contaminants in wastewater, there emanates some more aggressive, stealth and sinister groups of compounds. It is quite ironic that majority of these compounds are the ‘go through’ consumables in our present society and have been suspected to pose several health risks to the aquatic ecosystem, eliciting unfavourable clinical manifestations in aquatic animals and humans, which has heightened the uncertainties conferred on freshwater use and consumption of some aquatic foods. This review therefore serves to give a brief account on the metamorphosis of approach in detection of aromatic pollutants and ultimately their implications along the trophic chains in the community.
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