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Analysis and utilization of temple waste flowers in Coimbatore District Полный текст
2018
Elango, Gomathi | Govindasamy, Rathika
The present work deals with collection, handling, utilization, and management of the waste flowers that are coming out of the temples in Coimbatore District, Tamilnadu, India. An attempt has been made to provide a current situation and complete analysis of temple waste flowers (TWFs) with suggestions and recommendations. As a part of Clean India, Clean and Green Kovai (Green Coimbatore) mission, this paper gives an idea to reduce the volume of temple waste flowers by converting into activated carbon by direct pyrolysis process and chemical activation with sulfuric acid and phosphoric acid process, respectively. The products were analyzed and compared based on the results of physicochemical parameters including pH, conductivity, moisture content, ash content, volatile content, fixed carbon, bulk density, porosity, specific gravity, water soluble matter, acid soluble matter, iodine number, methylene blue number, yield, and Brunauer-Emmett-Teller (SBET) surface area. The structure, surface morphology, and chemical compositions of carbon were determined by field emission scanning electron microscopy (FeSEM), and energy-dispersive X-ray spectroscopy (EDS), respectively. From the comparison of results, the activated carbon produced from temple waste flowers by direct pyrolysis process is fairly better due to low moisture content, low ash content, better yield, and higher surface area.
Показать больше [+] Меньше [-]Reference intervals for B-esterases in gull, Larus michahellis (Nauman, 1840) from Northwest Spain: influence of age, gender, and tissue Полный текст
2018
Morcillo, SaloméMartínez | Perego, MariaChiara | Vizuete, Jorge | Caloni, Francesca | Cortinovis, Cristina | Fidalgo, LuisEusebio | López-Beceiro, Ana | Míguez, MaríaPrado | Soler, Francisco | Pérez-López, Marcos
Over the last years, cholinesterase (ChE) and carboxylesterase (CbE) activities have been increasingly used in environmental biomonitoring to detect the exposure to anticholinesterase insecticides such as organophosphorates (OPs) and carbamates (CBs). The aim of this study was to determine ChE and CbE enzymatic activities present in liver and muscle of yellow-legged gulls (Larus michahellis), a seabird species considered suitable to monitor environmental pollution. In order to provide reference data for further biomonitoring studies, the influence of different factors, such as gender, age, sampling mode, and tissue, was considered in the present study. Our data report a statistically significant difference in CbE enzymatic activity comparing liver and muscle samples (P < 0.05) along with an age-related CbE activity in liver samples (P < 0.05). Moreover, according to our results, capture method might influence CbE and ChE activity in both liver and muscle samples (P < 0.05). These findings underline the importance to assess basal levels of ChE and CbE activity considering, among other factors, gender-, age- and organ-related differences and confirm the suitability of Larus michahellis as a sentinel species especially within an urban environment.
Показать больше [+] Меньше [-]Metals in Diplodus sargus cadenati and Sparisoma cretense—a risk assessment for consumers Полный текст
2018
Afonso, Aridani | Gutiérrez, ÁngelJ. | Lozano, Gonzalo | González-Weller, Dailos | Lozano-Bilbao, Enrique | Rubio, Carmen | Caballero, JoséM. | Revert, Consuelo | Hardisson, Arturo
The increases in urbanization, demography and industrial activity, along with growing human needs which exploit the resources of the planet, have exponentially exacerbated pollution. In particular, the discharge of heavy metals into the marine ecosystem is a problem of global magnitude, as this may damage the diversity of marine species and ecosystems because of their toxicity, long persistence and bioaccumulation. Consequently, it is necessary to carry out an assessment of the risk of human exposure from the consumption of marine species potentially exposed to this type of pollutants. In the present study, the levels of toxic heavy metals (Cd, Pb and Al) as well as trace and essential metals (B, Ba, Co, Cu, Cr, Fe, Li, Mn, Mo, Ni, Sr, V and Zn) and macronutrients (Ca, K, Mg, Na) have been quantified in two species of fish for human consumption. In order to do this, a total of 80 muscle samples and 80 liver samples, belonging to two species of osteichthyes (bony fish), Diplodus sargus cadenati and Sparisoma cretense, were analyzed. The specimens studied were captured on the north coast of Gran Canaria (Canary Islands) using recreational fishing techniques. As they caught from the shore, the data obtained respond to the need to assess the toxic levels in two representative species of artisanal and recreational fishing in the area. The risk assessment indicated that these two fish species are safe for the average consumer; however, if the livers are frequently consumed, there may be potential risks because they exceed the Admissible Daily Intakes for Pb and Cd.
Показать больше [+] Меньше [-]Solar light-driven photocatalysis using mixed-phase bismuth ferrite (BiFeO3/Bi25FeO40) nanoparticles for remediation of dye-contaminated water: kinetics and comparison with artificial UV and visible light-mediated photocatalysis Полный текст
2018
Kalikeri, Shankramma | Shetty Kodialbail, Vidya
Mixed-phase bismuth ferrite (BFO) nanoparticles were prepared by co-precipitation method using potassium hydroxide as the precipitant. X-ray diffractogram (XRD) of the particles showed the formation of mixed-phase BFO nanoparticles containing BiFeO₃/Bi₂₅FeO₄₀ phases with the crystallite size of 70 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the formation of quasi-spherical particles. The BFO nanoparticles were uniform sized with narrow size range and with the average hydrodynamic diameter of 76 nm. The band gap energy of 2.2 eV showed its ability to absorb light even in the visible range. Water contaminated with Acid Yellow (AY-17) and Reactive Blue (RB-19) dye was treated by photocatalysis under UV, visible, and solar light irradiation using the BFO nanoparticles. The BFO nanoparticles showed maximum photocatalytical activity under solar light as compared to UV and visible irradiations, and photocatalysis was favored under acidic pH. Complete degradation of AY-17 dyes and around 95% degradation of RB-19 could be achieved under solar light at pH 5. The kinetics of degradation followed the Langmuir–Hinshelhood kinetic model showing that the heterogeneous photocatalysis is adsorption controlled. The findings of this work prove the synthesized BFO nanoparticles as promising photocatalysts for the treatment of dye-contaminated industrial wastewater.
Показать больше [+] Меньше [-]Characterization and application of microalgae hydrochar as a low-cost adsorbent for Cu(II) ion removal from aqueous solutions Полный текст
2018
Saber, Mohammad | Takahashi, Fumitake | Yoshikawa, Kunio
Hydrochar prepared from the hydrothermal liquefaction of microalgae is characterized and investigated for copper removal from aqueous solution. Two hydrochars were prepared at 210 °C (HD210) and 250 °C (HD250). The effect of the initial solution pH, the initial Cu(II) concentration, the contact time, and the temperature will be investigated. According to the elemental analysis, the volatile matter in the hydrochars was lower and ash content was higher than those of microalgae. Also, pore characteristic analysis revealed that the surface area of the HD250 was higher than that of the HD210 suggesting a higher potential for the adsorption process. FTIR analysis and Boehm titration showed that both hydrochars contained oxygen-containing functional groups (OFG) on the surface which were effective for the copper removal. The adsorption experiments indicated that the amount of copper adsorbed reached a maximum value at the pH of 5 which was considered as the optimum solution pH. In addition, HD250 had a higher amount of copper adsorption than that of HD210 at all values of the solution pH. The adsorption data at the optimum solution pH was well fitted by the Langmuir’s isotherm model and the adsorption process could be well described by the pseudo-2nd order kinetic model. Moreover, thermodynamic analysis revealed that copper adsorption onto the hydrochar was a physical endothermic process.
Показать больше [+] Меньше [-]Purifying arsenic and fluoride-contaminated water by a novel graphene-based nanocomposite membrane of enhanced selectivity and sustained flux Полный текст
2018
Pal, Madhubonti | Mondal, Mrinal Kanti | Paine, Tapan Kanti | Pal, Parimal
A novel graphene-based nanocomposite membrane was synthesized by interfacial polymerization (IP) through chemical bonding of the graphene oxide (GO) layer to polyethersulfone surface. Detailed characterization of the composite membrane through AFM, SEM, ATR-FTIR, XRD analysis, and Raman spectroscopy indicates strong potential of the membrane in highly selective removal of the toxic contaminants like arsenic and fluoride while permeating the essential minerals like calcium and magnesium. This makes the membrane suitable for production of safe drinking water from contaminated water. The membrane applied in a flat-sheet cross-flow module succeeded in removal of more than 98% arsenic and around 80% fluoride from contaminated water while selectively retaining the useful calcium and magnesium minerals in drinking water. A sustained pure water flux of around 150 LMH (liter per square meter per hour) during operation over long hours (> 150 h) with only 3–5% drop in flux indicates antifouling character of the membrane module.
Показать больше [+] Меньше [-]The association between serum copper concentrations and cardiovascular disease risk factors in children and adolescents in NHANES Полный текст
2018
Zang, Xiaodong | Huang, Hesuyuan | Zhuang, Zhulun | Chen, Runsen | Xie, Zongyun | Xu, Cheng | Mo, Xuming
Copper is an essential element in human beings, alterations in serum copper levels could potentially have effect on human health. To date, no data are available regarding how serum copper affects cardiovascular disease (CVD) risk factors in children and adolescents. We examined the association between serum copper levels and CVD risk factors in children and adolescents. We analyzed data consisting of 1427 subjects from a nationally representative sample of the US population in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014. The CVD risk factors included total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, fasting glucose, glycohemoglobin, fasting insulin, and blood pressure. Multivariate and generalized linear regressions were performed to investigate associations adjusted for age, gender, ethnicity, poverty:income ratio (PIR), BMI, energy intake, and physical activity. We found significant associations between serum copper and total cholesterol (coefficient = 0.132; 95% CI 0.081, 0.182; P for trend < 0.001), glycohemoglobin (coefficient = 0.044; 95% CI 0.020, 0.069; P < 0.001), and fasting insulin (coefficient = 0.730; 95% CI 0.410, 1.050; P < 0.001) among the included participants. Moreover, in the generalized linear models, subjects with the highest copper levels demonstrated a 0.83% (95% CI 0.44%, 1.24%) greater increase in serum total cholesterol (p for trend < 0.001) when compared to participants with the lowest copper concentrations. Our results provide the first epidemiological evidence that serum copper concentrations are associated with total cholesterol concentrations in children and adolescents. However, the underlying mechanisms still need further exploration.
Показать больше [+] Меньше [-]UVΑ pre-irradiation to P25 titanium dioxide nanoparticles enhanced its toxicity towards freshwater algae Scenedesmus obliquus Полный текст
2018
Roy, Barsha | Chandrasekaran, Hemamalini | Palamadai Krishnan, Suresh | Chandrasekaran, Natarajan | Mukherjee, Amitava
There has recently been an increase in the usage of TiO₂ nanoparticles (NPs). P25 TiO₂ NPs, a mixture of anatase and rutile phase in 3:1 ratio, are generally used for photocatalytic applications because both phases exhibit a synergistic effect on the photocatalytic activity of the TiO₂ NPs. In the present study, increased toxicity of UVA-pre-irradiated P25 TiO₂ NPs on freshwater algae Scenedesmus obliquus was assessed under visible light and dark exposure conditions at actual low concentrations (0.3, 3 and 35 μM of Ti). Photocatalytic property of P25 TiO₂ NPs caused disaggregation of UVA-pre-irradiated NPs, thus significantly decreasing the mean hydrodynamic diameter (MHD) (188.74 ± 0.54 nm) than that of non-irradiated NPs (232.26 ± 0.44). This decrease in diameter of UVA-pre-irradiated NPs may increase its biological activity towards algal samples. All concentrations of pre-irradiated NPs, under both light and dark conditions, showed a significantly lesser cell viability (p < 0.001) when compared with non-irradiated NPs. Increased production of ROS, antioxidant enzymes and lipid peroxidation supported the viability data. Higher exopolysaccharide production and more nuclear damage were observed for pre-irradiated NPs. NP uptake was also more for the pre-irradiated NPs on treated samples when compared with non-irradiated NPs on treated samples, which, in turn, established the higher toxic potential of UVA-pre-irradiated TiO₂ NPs. This study improves our understanding of the toxic effects of UVA-pre-irradiated TiO₂ NPs on freshwater algae, thereby emphasising the need for ecological risk assessments of metal oxide nanoparticles in a natural experimental medium.
Показать больше [+] Меньше [-]Sediment evidence of industrial leakage-induced asynchronous changes in polycyclic aromatic hydrocarbons and trace metals from a sub-trophic lake, southwest China Полный текст
2018
Wang, Lei | Chen, Guangjie | Kang, Wengang | Wang, Jiaoyuan | Liu, Yuanyuan | Chen, Li
It has been well established that regional patterns of atmosphere-borne polycyclic aromatic hydrocarbons (PAHs) and trace metals were predominantly associated with the trajectory of socio-economic development; however, they could be potentially modulated by anthropogenic fingerprint of local sources such as industrial spill. Here, we established historical pollution data of both PAHs and trace metals from a well-dated sediment core from Yangzong Lake of Southwest China, which experienced a severe tailing leakage accident derived from a zinc concentrate smelting plant in 2007, aiming to evaluate the heterogeneity in their temporal trajectories and their sources of contamination in the context of regional deposition patterns. Sedimentary records show that the concentrations and fluxes of both PAHs and trace metals remained a consistently low level before the 1950s. An increasing trend and the synchronous changes of both PAHs and trace metals during ~ 1950–2002 were well consistent with the temporal pattern of socio-economic development in western China, with coal combustion and smelting industries as the main sources of contamination in this region. However, arsenic (As) and PAHs exhibited a concurrent spike for the period of ~ 2007–2013, contrasting strongly to the regional pattern of these contaminants. The modern concentrations of As revealed a 5- to 14-fold increase over the pre-1950 level, with the contemporary concentrations of PAHs rising by ~ 10–14 times. The sediment records reveal that local fingerprints of smelting activities in the catchment of Yangzong Lake have overridden the temporary pattern of regional atmosphere-borne As and PAHs over the last decade. This highlights the important role of local pollution sources in modulating or even overriding the regional pattern of anthropogenic contamination in highly impacted systems.
Показать больше [+] Меньше [-]A hierarchical testing strategy for micropollutants in drinking water regarding their potential endocrine-disrupting effects—towards health-related indicator values Полный текст
2018
Kuckelkorn, Jochen | Redelstein, Regine | Heide, Timon | Kunze, Jennifer | Maletz, Sibylle | Waldmann, Petra | Grummt, Tamara | Seiler, Thomas-Benjamin | Hollert, Henner
In Germany, micropollutants that (may) occur in drinking water are assessed by means of the health-related indicator value (HRIV concept), developed by the German Federal Environment Agency. This concept offers five threshold values (≤ 0.01 to ≤ 3 μg l⁻¹) depending on availability and completeness of data regarding genotoxicity, neurotoxicity, and germ cell-damaging potential. However, the HRIV concept is yet lacking integration of endocrine disruptors as one of the most prominent toxicological concerns in water bodies, including drinking water. Thresholds and proposed bioassays hence urgently need to be defined. Since endocrine disruption of ubiquitary chemicals as pharmaceuticals, industrial by-products, or pesticides is a big issue in current ecotoxicology, the aim of this study was to explore endocrine effects, i.e., estrogenic and androgenic effects, as an important, additional toxicological mode of action for the HRIV concept using a hierarchical set of well-known but improved bioassays. Results indicate that all of the 13 tested substances, industrial chemicals and combustion products (5), pharmaceuticals and medical agents (4), and pesticides and metabolites (4), have no affinity to the estrogen and androgen receptor in human U2OS cells without metabolic activation, even when dosed at their water solubility limit, while in contrast some of these substances showed estrogenic effects in the RYES assay, as predicted in pre-test QSAR analysis. Using a specifically developed S9-mix with the U2OS cells, those micropollutants, i.e., Benzo[a]pyrene, 2,4-Dichlorophenol, 3,3-Dichlorbenzidin, 3,4-Dichloranilin, and diclofenac, they show estrogenic effects at the same concentration range as for the yeast cells. Three of the drinking water-relevant chemicals, i.e., atrazine, tributyltin oxide, and diclofenac, caused effects on hormone production in the H295R assay, which can be correlated with changes in the expression of steroidogenic genes. One chemical, 17α-Ethinylestradiol, caused an estrogenic or anti-androgenic effect in the reproduction test with Potamopyrgus antipodarum. Considering these results, a proposal for a test strategy for micropollutants in drinking water regarding potential endocrine effects (hormonal effects on reproduction and sexual development) will be presented to enhance the existing HRIV concept.
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