Zobrazení zdroje stránky Klausenalexander6862

Although the methodology used in this study provides a simplified assessment of the likelihood of damage to UNESCO's cultural heritage in Europe from air pollution, it provides a unique perspective and the potential risk is assessed on a common basis. The results obtained contribute to a better understanding of the existing risk deriving from atmospheric pollution and to highlighting those sites, generally located in areas where anthropogenic activity is relevant, that need particular attention. The present paper can serve as a basis for stimulating additional studies and site-specific analyzes, as well as highlighting the need for further measures and policies for atmospheric pollution reduction in cities and in the surroundings of sensitive historic buildings and monuments to prevent further damage.Allelopathy is regarded as an economic and eco-friendly approach for the control of harmful algal blooms (HABs) because allelochemicals degrade easily and cause less pollution than traditional algicides. We first surveyed the inhibitory effect of the traditional medicinal plant Cerbera manghas L. on the notorious dinoflagellates Alexandrium tamarense, Scrippsiella trochoidea, and Karenia mikimotoi. Then, we identified and quantified the potential algicidal compounds by UPLC-MS and determined their activity. The aqueous extract inhibited algae with EC50-120 h at 0.986, 1.567 and 1.827 g L-1 for A. tamarense, S. trochoidea, and K. mikimotoi, respectively. Three potential allelochemicals were quantified in the stock solution quinic acid (QA) (28.81 mg L-1), protocatechuic acid (PA) (53.91 mg L-1), and phloridzin (PD) (26.17 mg L-1). Our results illustrated that 1) QA did not have an inhibitory effect, 2) PA had medium toxicity to algae (EC50-120h 0.22, 0.28, and 0.35 mM for A. tamarense, S. trochoidea, and K. mikimotoi), and 3) PD had low toxicity (EC50-120h &gt; 0.66 mM). These findings suggested that PA might be the main allelopathic compound in the aqueous extract of the studied algae. In addition, PA could have a negative effect on the photosynthesis of S. trochoidea by impeding the reduction of quinone electrons and destroying electron transfer in PSII. In summary, this was the first study to quantify allelochemicals in C. manghas fruit. Moreover, C. manghas and protocatechuic have the potential to be algicides to control and mitigate the HABs caused by dinoflagellates.This study aimed to evaluate the influence of two different feeding modes on wastewater treatment performance and oxygen consumption rate (OCR) of the unsaturated (UVF wetland) and partially saturated (SVF wetland) vertical flow constructed wetlands operated in parallel under subtropical climate for four years. Each wetland had a superficial area of 7.5 m2 and was planted with Typha domingensis. Both units have a filter media depth of 0.75 m, composed by sand (effective diameter of 0.29 mm and uniformity of 4). UVF wetland operated typically unsaturated, while SVF wetland had the bottom part saturated (57% of total depth). Two feeding modes were evaluated for both wetlands. The feeding mode was operated within the limits recommended by the German standard, with a hydraulic loading rate (HLR) of 75 mm d-1 and specific pulse volume (SPV) of 19 L m-2 for both wetlands and a specific hydraulic loading rate (SHLR) of 8 and 9 L m-2 min-1 for UVF and SVF wetlands, respectively. Meanwhile, the second feeding mode was applied for both wetlands, being an HLR of 103 mm d-1, 26 L m-2 of SPV, and 4 L m-2 min-1 of SHLR. The load removal efficiency of SVF wetland was higher than the UVF wetland for all parameters and feeding modes. No statistical difference was identified for OCR values between wetlands and feeding mode. The results showed that operating UVF and SVF wetlands with a SHLR around 4 L m-2 min-1 and SPV equal of 26 L m-2 is preferable. This fact could represent a significant reduction in inlet pumping power requirements and also less superficial area requirements.A large increase in carbon emission and other greenhouse gases have attracted much attention around the world for decades. As the second largest carbon emission source in the world, the agricultural carbon emission and the environmental improvement value of agricultural carbon reduction (EIVACR) should not be ignored. Based on the theory of resource economic value, the current study divided 31 provincial-level administrative units of China into three major regions. The Super-Efficiency Slacks-Based Measurement (SBM) model, Moran's I index and Markov chain transfer probability matrix method have been employed to examine EIVACR and it's spatial-temporal dynamic evolution characteristics by adopting panel data of 31 provinces from 1997 to 2017. The result indicated that (i) during the study period, China's average EIVACR showed significant regional differences, accompanied by the gradually strengthening spatial pattern of the "central &gt; western &gt; eastern"; (ii) the average EIVACR increased from 0.970 Million Yuan in 1997 to 1.164 Million Yuan in 2017, increasing by 20% in 21 years; (iii) no spatial correlation or obvious dependence exist between adjacent provinces, but present a negative impact of "high-low" agglomeration in individual years; (iv) the influencing effects of technology adoption and factor allocation have spatial heterogeneity, and the influencing effect of policy orientation has temporal heterogeneity. Therefore, differentiated carbon reduction policies should be formulated according to regional and temporal differences. Meanwhile, carbon reduction market trading mechanism and compensation policy should be established. What's more, regional cooperation needs to be strengthened, to form a synergistic carbon reduction effect.Understanding the behavior and risk of nanoparticles (NPs) in the aquatic environment is currently limited by the lack of quantitative characterization of NPs in the environmental matrices, such as sediments. In this study, based on the single particle (SP)-ICP-MS technique, metal-containing NPs, including Ti- and Zn-containing NPs, were analyzed in sediments taken along the Yangtze Estuary. Combined with the traditional sequential extraction method that has been widely used for metal risk assessment, different single extraction methods were used to understand the association of NPs with different chemical fractions in sediments and their potential environmental implications. Ti-containing NPs, with an average size of 81 nm, ranged from 3.02 × 107 parts/mg to 9.61 × 107 parts/mg, and Zn-containing NPs, with an average size of 41 nm, ranged from 2.47 × 106 parts/mg to 1.21 × 107 parts/mg. Both correlation and redundancy analyses showed that particle concentrations of Ti-containing NPs in sediment were significantly correlated to the Ti-containing NPs in the residual fraction and salinity, indicating that Ti-containing NPs in sediments may be dominated by Ti-containing NPs in the residue fractions of sediments. Large amounts of these NPs may be released from the residual fraction that has been considered to be not bioavailable and "environmentally safe" in the traditional environmental risk assessment of metals in sediments. Zn-containing NPs, mostly associated with carbonates, were positively correlated to all the bioavailable fractions of Zn in sediments, suggesting that these NPs may be largely presented in the bioavailable fraction. This study showed that, vast numbers of NPs with minute sizes were present in estuarine sediments, and that they were associated with different chemical fractions with different potential environmental risks. The study findings call for further research to update the traditional risk assessment method.N-doped carbon materials have been proven to be effective catalysts for activating peroxymonosulfate (PMS). Marine algae biomass is rich in nitrogenous substances , which can reduce the cost of N-doping process and can obtain excellent N-doped catalysts cheaply and easily. In this study, kelp biomass was selected to prepare N-doped kelp biochar (KB) materials. The high defect degree, high specific surface area, and participation of graphite N make KB have excellent catalytic degradation ability. The KB degraded 40 mg/L ofloxacin (OFL) close to 100% within 60 min, applied with PMS. Through quenching experiments and electron paramagnetic resonance spectroscopy, the degradation process dominated by non-radical pathways was determined. At the same time, O2·- and 1O2 were closely related, and a significant impact of quenching O2·- on the reaction was observed. The non-radical approach made the system excellent performance over a wide pH range and in the presence of multiple anions. The experiments of reusability confirmed the stability of the material. Its catalytic performance was restored after low-temperature pyrolysis. This research supports the use of endogenous nitrogen in biomass. It provides more options for advanced oxidation process application and marine resource development.Antibiotic resistance containment strategies at wastewater treatment plants need to be supported by a firm knowledge on the behavior of resistant bacteria within a diverse microbial population in the presence of trace amount of antibiotics. In this study via investigating the population dynamics of resistant/sensitive Staphylococcus aureus co-cultures in several model wastewater matrix systems, valuable insights were obtained into the effect of trace amount of antibiotics (piperacillin and erythromycin) on bacteria, and into the suitability of advanced oxidation treatment (electron beam irradiation) as a remediation measure. It appears that environmentally relevant concentration levels of the antibiotic present in a wastewater matrix leads to a shift in the population in favor of the sensitive subtype, presumably on account of triggering protective biochemical processes in the resistant mutant, which confer no selective advantage since the sensitive strain remains unaffected in this concentration range. The impact of these conditions on the population dynamics can be diminished by using advanced oxidation treatment, considering that degradation products from the wastewater matrix constituents (such as humic acid) might also have an effect. Furthermore, it became also apparent that the presence of trace amount of antibiotics while triggers biological processes in the resistant subtype, concomitantly makes the bacteria more sensitive towards the attack of free radicals during advanced oxidation treatment. [https://www.selleckchem.com/products/c-75.html C75 supplier] The behavior of resistant bacteria under environmental conditions at the cellular and population level clearly merits more attention.The contribution of Diffusive Gradients in Thin films (DGT) passive sampling to continental water quality monitoring was assessed in a real measurement network (6 sampling campaigns, 17 stations). Ten metals/metalloids (Al, Zn, Ni, Cd, Cu, Pb, Cr, As, Se and Sb) were studied using the control laboratory's working conditions with grab and DGT passive sampling. The DGT field deployments were robust, with a 3% sampler loss rate and a less then 65% average relative deviation between duplicates. Compared to grab sampling, DGT showed a similar quantification frequency for half of the targeted elements but showed a higher frequency for the other half (e.g., Cd quantification at 20% with grab sampling vs. 97% with DGT). Similar concentration trends were established using DGT and grab sampling at most sites throughout the year. Notably, for some elements, trends were only provided by DGT sampling. A study of several DGT blanks showed that the device contamination was occasional and originated primarily from cross-contamination during the disassembly step.