Δευτέρα 29 Ιουλίου 2019

Cellular distribution of cadmium in two amaranth ( Amaranthus mangostanus L.) cultivars differing in cadmium accumulation
The article Cellular distribution of cadmium in two amaranth (Amaranthus mangostanus L.) cultivars differing in cadmium accumulation, written by Keyu Chi, Rong Zou, Li Wang, Wenmin Huo and Hongli Fan, was originally published electronically on the publisher’s internet portal (currently SpringerLink)

Correction to: One-step synthesis of versatile magnetic nanoparticles for efficiently removing emulsified oil droplets and cationic and anionic heavy metal ions from the aqueous environment
On page 6156, “Regeneration of the MNPs for Cu(II) and Cr(VI) adsorption was conducted by using 0.1 mol/L HCl solution and NaOH solution as eluents, respectively” should read “Regeneration of the MNPs for Cu(II) and Cr(VI) adsorption was conducted by using 1.0 mol/L HCl solution and NaOH solution as eluents, respectively”.

Correction to: Monte Carlo fingerprinting of the terrestrial sources of different particle size fractions of coastal sediment deposits using geochemical tracers: some lessons for the user community
The original publication of this paper contains a mistake. The correct University name of the 3rd affiliation is shown in this paper.

Extreme pollution, climate change, and depression

Determination of Alternaria toxins in drinking water by ultra-performance liquid chromatography tandem mass spectrometry

Abstract

A sensitive and reliable analytical method has been developed and validated for the determination of five Alternaria toxins, including tenuazonic acid (TeA), alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), and tentoxin (TEN), in drinking water using a one-step enrichment and clean-up strategy followed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Drinking water samples were preprocessed using excess sodium sulfite to remove residual chlorine, and the pH was adjusted by formic acid. Analytes were concentrated and purified from the water samples using hydrophilic-lipophilic balanced (HLB) solid-phase extraction (SPE) cartridges. Chromatographic separation was performed on an Acquity HSS C18 column using 0.1 mM ammonium carbonate and methanol as the mobile phase. The average recoveries at three spiked levels (0.1, 0.5, and 1 ng/L for TeA, AOH, and ALT; 0.01, 0.05, and 0.1 ng/L for TEN and AME) were 76.1–106.5%, with an intra-day precision less than 15.5% and inter-day precision of 11.8–16.5%. The limits of detection (LODs) were 0.05 ng/L for TeA, AOH, and ALT and 0.005 ng/L for TEN and AME. The limits of quantification (LOQs) were 0.1 ng/L for TeA, AOH, and ALT and 0.01 ng/L for TEN and AME. The developed method was applied to monitor 289 drinking water samples collected in Beijing from 2015 to 2017, and TeA and TEN were found in 28 samples, with concentrations ranging from 0.16 to 2.7 ng/L and 0.21 to 2.2 ng/L, respectively.

Identification of allelochemicals from pomegranate peel and their effects on Microcystis aeruginosa growth

Abstract

This paper studied the inhibitory effect of pomegranate peel (PP) extract on the growth of Microcystis aeruginosa, the model of harmful algal blooms in aquatic environment. The allelochemicals were identified by HPLC–MS/MS from PP and tested by batch experiment through measurement of algal density, chlorophyll a (Chl-a) concentration, maximum quantum yield of photosystem II (Fv/Fm), superoxide dismutase (SOD), and malondialdehyde (MDA) contents. Results showed that both PP powder and PP extract had obvious inhibitory effect on M. aeruginosa growth. Quercetin and luteolin were identified as the allelochemicals to M. aeruginosa growth. However, the inhibitory capacity of luteolin was stronger than that of quercetin. The growth inhibition ratio of luteolin can reach up to 98.7 and 99.1% of the control on day 7 at the dosages of 7 and 10 mg/L, respectively. Moreover, the changes of Chl-a, Fv/Fm, SOD, and MDA in M. aeruginosa confirmed jointly that the allelochemicals cause inhibition of photosystem and oxidative damage to M. aeruginosa cells with the antioxidant defense system being activated, which leads to the aggravation of membrane lipid peroxidation. Thus, luteolin could be used as a promising algaecide for emergency handling of M. aeruginosa blooms. This study might provide a new direction in the management of eutrophication in the future.

Effects of energy consumption, economic growth, and financial development on carbon emissions: evidence from heterogeneous income groups

Abstract

This paper examines the effects of energy consumption, economic growth, and financial development on carbon emissions in a panel of 122 countries. We employ both first-generation and second-generation cointegration and estimation procedures in order to address diverse economic and econometric issues such as heterogeneity, endogeneity, and cross-sectional dependence. We find a cointegration relationship between the variables. Energy consumption, economic growth, and financial development have detrimental effects on carbon emissions in the full sample. When the sample is split into different income groups, we reveal that economic growth and financial development mitigate carbon emissions in high-income group but have the opposite effects in low-income and middle-income groups. The implication of the findings is that energy consumption increases carbon emissions. While high levels of income and financial development decrease carbon emissions, low levels of income and financial development intensify it. Based on the findings, the paper makes some policy recommendations.

Public health risk of heavy metal residues in meat and edible organs of broiler in an intensive production system of a region in Pakistan

Abstract

The aim of this study was to find the concentration of lead (Pb), cadmium (Cd), nickel (Ni), manganese (Mn), and zinc (Zn) in feed, drinking water, and their residues in meat and internal organs in broilers at three different locations in Charsadda. For this purpose, a total of 48 representative water and feed samples and 240 meat and internal organs of broilers were collected. Significantly (P < 0.05) higher concentrations of Zn and Mn were found in feed samples. In water samples assessed for heavy metals, a significantly (P < 0.05) higher concentration of Pb was observed at Umerabad and Kula Dher as compared with Nisatta whereas a significantly (P < 0.05) higher concentration of Ni was recorded at Umerabad as compared with Nisatta and Kula Dher. Similarly, a significantly (P < 0.05) higher concentration of Mn in water was recorded at Kula Dher as compared with Nisatta and Umerabad. The concentration of Pb in water at all locations and the concentration of Ni at Umerabad were above the maximum permissible limits. A significantly (P < 0.05) higher concentration of Pb in the liver, breast, and thigh muscles and a significantly (P < 0.05) higher concentration of Mn in the liver, gizzard, breast, and thigh muscles of broilers were recorded at Kula Dher. A significantly (P < 0.05) higher mean concentration of Pb, Cd, Ni, Mn, and Zn was recorded in the liver as compared with the gizzard, breast, and thigh muscles. It was concluded from the present study that broiler farms near the roadside/canal and waste disposal site/wastewater drains cause accomulaiton of high concentrations of some heavy metals in meat and internal organs of broiler birds.

Analysis of rainfall infiltration and its influence on groundwater in rain gardens

Abstract

The dynamic observation data on groundwater level and water quality were obtained from rain gardens #2 and #3 from May to October 2016. The water balance method and 2D numerical simulation of variable saturation zone were used to calculate rainfall infiltration recharge coefficient, water supply, and evaporative discharge of rain garden. These parameters were used to simulate and explore the impact of rainfall infiltration in rain gardens on groundwater level and water quality. The groundwater depth of rain gardens was mainly affected by the concentrated infiltration of rainfall. The variation range of groundwater depth was approximately 4.298 ± 0.031 mm for J1, 3.9364 ± 0.097 mm for J2, and 4.0958 ± 0.064 mm for J3, and the specific yield was 0.208. Groundwater quality was naturally attenuated and would not threaten the safety of groundwater at a certain scale. Visual MODFLOW was used to simulate groundwater flow and conduct parameter sensitivity analysis to determine the main influencing factors of garden groundwater level change. Results showed that rainfall recharge was crucial to module sensitivity.

Environmental impact of combustion of ethanolic biodiesel/diesel blends from several feedstocks on the gas emission levels in the atmosphere

Abstract

The aim of this work was to evaluate simultaneously the effect of produced ethanolic biodiesel from several feedstocks (soybean, crambe, macaw, sunflower, and waste cooking oil) and engine operational conditions (low and high engine speed) during combustion of biodiesel/diesel blends on the N2O, NOx, NO, CO2, and CO emission levels in the atmosphere. The biodiesel samples were prepared in one and/or two reaction steps, according to the acid index of each raw material, by esterification using H2SO4 and/or chemical transesterification using sodium ethoxide, both, through ethanolic route. The quality of the produced biodiesels was confirmed by ASTM/EN specifications. Then, biodiesel/diesel blends were prepared according to the following proportions: 10% (B10), 15% (B15), 25% (B25), and 50% (B50). In general way, all raw materials under combustion at low and high engine speed contributed to the formation of NOx and this effect was more drastically increased as the biodiesel concentration in the blends increases. N2O presented a similar behavior except for blends containing crambe and macaw biodiesel whose emissions were slightly reduced as a function of biodiesel content in these blends. Then, Principal component analysis (PCA) was applied to discriminate the effect of engine operating conditions, biodiesel kind, and biodiesel content in the blends during their combustion on the exhaust emissions. The attained results point to crambe and macaw as more environmentally sustainable feedstocks for biodiesel production because they generate less greenhouse gas emissions. These results are particularly attractive considering that, both, crambe and macaw are non-edible feedstocks with great potential for biodiesel production.

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