Environmental Science and Pollution Research - This study aims to find the interaction between ionome and metabolome profiles of Pteris vittata L., an arsenic hyperaccumulator plant, to reveal its... 相似文献
Cyprodinil and thiacloprid are two of the most commonly used pesticides in Turkey. It is more likely to reach humans or animals due to their widespread use. This study aims to investigate whether there is a DNA damage risk due to cyprodinil and thiacloprid exposure. Zebrafish, which is used as a model organism in health and environmental research, and comet assay were chosen to demonstrate this damage. Ten zebrafish per group were exposed to 2 different concentrations for each pesticides (0.31 and 0.155 mg/L for cyprodinil and 1.64 and 0.82 mg/L for thiacloprid) for 21 days. After, gills were excised and comet assay was performed. Photos of an average of 50 cells per slide were taken and were analyzed with visual evaluation program. DNA damage was found to be increased in the 0.31 mg/L cyprodinil, 0.82 mg/L thiacloprid, and 1.64 mg/L thiacloprid treatment groups when compared to the control group (p < 0.001). Average tail DNA percentage parameter values were 9.45 ± 0.51, 10.30 ± 0.34, 11.17 ± 0.33, and 2.47 ± 0.06 respectively. Cyprodinil and thiacloprid were identified as genotoxic agents that should be investigated further.
To obtain basic information for evaluating critical levels of O3 under different nitrogen loads for protecting Japanese beech forests, two-year-old seedlings of Fagus crenata Blume were grown in potted andisol supplied with N as NH4NO3 solution at 0, 20 or 50 kg ha−1 year−1 and exposed to charcoal-filtered air or O3 at 1.0, 1.5 and 2.0 times the ambient concentration from 16 April to 22 September 2004. The O3 induced significant reductions in the whole-plant dry mass, net photosynthetic rate at 380 μmol mol−1 CO2 (A380), carboxylation efficiency (CE) and concentrations of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and total soluble protein (TSP) in the leaves.
The concentrations of Rubisco and TSP were negatively correlated with the concentration of leaf acidic amino acid, suggesting
that O3 enhanced the degradation of protein such as Rubisco. The N supply to the soil did not significantly change the whole-plant
dry mass and A380, whereas it significantly increased the CE and concentrations of Rubisco and total amino acid. No significant interactive effects of O3 and N supply to the soil were detected on the growth, photosynthetic parameters and concentrations of protein and amino acid
in the leaves. In conclusion, N supply to the soil at ≤50 kg ha−1 year−1 does not significantly change the sensitivity to O3 of growth and net photosynthesis of Fagus crenata seedlings. 相似文献
Airborne particulate matter (APM) is a major air pollutant, and the effect on human health of fine APM (PM2.5) deposited deep inside the lungs has recently become a serious concern. Moreover, soluble constituents may leach from APM, and intensify some health disorders. To identify the soluble chemical constituents of APM, size-classified APM was sampled in central Tokyo, and the elemental compositions of the water-soluble, acid-soluble and insoluble fractions were investigated. The extraction procedure was validated by calculating the mass balance of soluble and insoluble fractions of a standard APM reference material (NIST SRM 1648). Among the major elements, Fe and Ti in APM of all size classes and K in coarse APM were distributed primarily in the insoluble fraction and were inferred to be present as oxides or silicates, whereas Na and Mg in all size classes and K in fine APM were primarily in the water-soluble fraction and were inferred to be have originated mainly from sea salt. Among the trace elements, Zn and Cd in the fine APM (d < 2 microm) had large enrichment factors, indicating an anthropogenic origin, and were distributed primarily in the water-soluble fraction. When fine anthropogenic APM enters into the lungs, leached toxic elements, such as Cd, may adversely affect health. The higher the bonding energy of the monoxide molecule of the element was, the higher its distribution ratio was in the water-soluble fraction. Therefore, many metallic elements in APM were inferred to be present as oxygen-bonded compounds. 相似文献
This paper describes the possible inundation scenarios under sea level rise conditions due to global climate change with particular reference to Nagoya, Japan. The study was carried out by using a two-dimensional sea model integrated with one-dimensional river flow model and two-dimensional overland flow model. For the connections of models, the upstream discharge or downstream water level in each grid is considered as the boundary conditions. The governing equations used for the analysis have been solved by finite volume method. The analysis results implicate that some parts of densely populated coastal area of Nagoya city will be vulnerable to inundation if the sea level rise due to global warming by 1 m. Moreover, the performances of existing sewer system and inundation scenario under various conditions have been analyzed. 相似文献
To date, non-food vegetable oil has been considered as the primary source for biodiesel production. Rubber seed oil has high acid value (34 mgKOH/g) and can be used for biodiesel synthesis. The purpose of this study was to investigate esterification of fatty acid, which derived from rubber seed oil, in a plug flow reactor system at high temperature and low methanol consumption. Response surface methodology was applied for design experiment and optimization of esterification reaction. Temperature, methanol consumption, and sulfuric acid were chosen as variables to examine their influence in a conversion to methyl ester. At 140°C, at 5:1 methanol to fatty acid ratio (by mole), H2SO4 1.5 (%v/w), and space time 20 min, the conversion to methyl ester attained 98.2%. Fourier transform infrared spectroscopy (FTIR) and gas chromatography-Mass spectrometry (GC-MS) were used for analysis and to confirm the formation of methyl ester. Methyl ester was characterized for biodiesel fuel properties in accordance to ASTM standard. 相似文献
Abstract This paper introduces a predictive mechanism for elemental mercury (Hg0) oxidation on selective catalytic reduction (SCR) catalysts in coal-fired utility gas cleaning systems, given the ammonia (NH3)/nitric oxide (NO) ratio and concentrations of Hg0 and HCl at the monolith inlet, the monolith pitch and channel shape, and the SCR temperature and space velocity. A simple premise connects the established mechanism for catalytic NO reduction to the Hg0 oxidation behavior on SCRs: that hydrochloric acid (HCl) competes for surface sites with NH3 and that Hg0 contacts these chlorinated sites either from the gas phase or as a weakly adsorbed species. This mechanism explicitly accounts for the inhibition of Hg0 oxidation by NH3, so that the monolith sustains two chemically distinct regions. In the inlet region, strong NH3 adsorption minimizes the coverage of chlorinated surface sites, so NO reduction inhibits Hg0 oxidation. But once NH3 has been consumed, the Hg0 oxidation rate rapidly accelerates, even while the HCl concentration in the gas phase is uniform. Factors that shorten the length of the NO reduction region, such as smaller channel pitches and converting from square to circular channels, and factors that enhance surface chlorination, such as higher inlet HCl concentrations and lower NH3/NO ratios, promote Hg0 oxidation. This mechanism accurately interprets the reported tendencies for greater extents of Hg0 oxidation on honeycomb monoliths with smaller channel pitches and hotter temperatures and the tendency for lower extents of Hg0 oxidation for hotter temperatures on plate monoliths. The mechanism also depicts the inhibition of Hg0 oxidation by NH3 for NH3/NO ratios from zero to 0.9. Perhaps most important for practical applications, the mechanism reproduces the reported extents of Hg0 oxidation on a single catalyst for four coals that generated HCl concentrations from 8 to 241 ppm, which covers the entire range encountered in the U.S. utility industry. Similar performance is also demonstrated for full-scale SCRs with diverse coal types and operating conditions. 相似文献
Concentrations of 14 rare earth elements (REEs) in six size classes of airborne particulate matter (APM) (<0.43, 0.43-0.65, 0.65-1.1, 1.1-2.1, 2.1-11, and >11 μm) and in two different phases (suspended particulate and dissolved) in rainwater were determined by inductively coupled plasma mass spectrometry (ICP-MS). Positive Eu and Tb anomalies were observed in size-classified APM. These anomalies may be due to large emissions of Eu and Tb to the atmosphere resulting from the recent change in Japan from the use of cathode-ray tubes to plasma displays in television sets (Eu and Tb) and from the widespread use of magneto-optical disks (Tb). The light REEs were enriched in fine APM particles (diameter < 1.1 μm). Because compositions of La/Ce/Sm in fine APM (diameter < 1.1 μm) were similar to those in automobile catalyst, the light REE enrichment was attributed to automobile emissions. In contrast, the REE distribution pattern in the suspended particulate phase in rainwater was similar to that in coarse APM (diameter > 2.1 μm), and a positive Tb anomaly was observed, suggesting that coarse particles easily become trapped in rain droplets. A negative Eu anomaly was observed in the dissolved phase in rainwater, but not in APM or in the suspended particulate phase in rainwater. Unlike other REEs, Eu can exist as both bivalent and trivalent ions in nature, and Eu-selective dissolution from or adsorption onto the trapped particles of Eu might account for the negative anomaly. These results show that atmospheric REE cycling is affected by the physico-chemical properties of APM. 相似文献