Nortonwaddell0141

In this work, nitrogen-doped carbon nanoshell structure with the encased Fe0/Fe3C nanoparticles (Fe@NC) was synthesized with a solvent-free method via direct carbonizing the ground mixture of dicyandiamide and ferric chloride hexahydrate. ABC294640 clinical trial The morphology, structure, and surface properties of as-synthesized Fe@NC were characterized systematically, and the removal performance of Fe@NC towards U(VI) was studied in detail. The results manifested that the Fe@NC possessed large surface area (127.0 m2/g) with mesoporosity and the encapsulated Fe0/Fe3C nanoparticles were concentrated at the tip of N-doped carbon nanotubes. Moreover, the Fe@NC hybrid material exhibited the maximum removal capacities of 0.85 and 0.44 mg/m2 at pH 4.5 and 1.5, respectively. The mechanism of U(VI) removal by the Fe@NC was attributed to the synergistic effects of adsorption via nitrogen/oxygen-containing groups and redox reaction between Fe0/Fe2+ and U(VI). In this report, polygonal angle platinum nanoparticles (PtNPs) anchored on nitrogen doping reduced graphene oxide (NrGO) as oxygen reduction reaction (ORR) catalyst was synthesized by gamma irradiation assisted with in situ hydrolysis of urea without using any shape inducer, seed, or template. Urea was not only employed as the nitrogen source, but also offered more reductive radicals in the gamma system. The uniform dispersion and homogeneous size distribution of PtNPs are obtained on reduced graphene oxide (rGO), which is attributed to the synergy of restriction effects of GO and crush capacity of high energy gamma rays. In addition, the method simultaneously offers PtNPs with polygonal angle structure and doping nitrogen in rGO, thus provides more surface and corner defects on PtNPs and heteroatomic defects on rGO, which synergistically improve the ORR performance of the samples. The obtained polygonal angle PtNPs modified NrGO exhibit fantabulous ORR activity in alkaline media with enhanced onset potential (906 mV), half-wave potential (783 mV) and superior limit current density (6.74 mA·cm-2) compared to the commercial Pt/C and those PtNPs supported on rGO composites. The results indicate that gamma irradiation assisted with in situ hydrolysis of urea can be a promising candidate method for preparation of high performance Pt-based catalysts in practical application. Xylenes are important aromatic hydrocarbons having broad industrial emissions and profound implication to air quality and human health. Generally, homogeneous atmospheric oxidation of xylenes is initiated by hydroxyl radical (OH) resulting in minor H-abstraction and major OH-addition pathways. However, the effect of mineral particles on the homogeneous atmospheric oxidation mechanism of xylenes is still not well understood. In the present study, the heterogeneous atmospheric oxidation of xylenes on mineral particles (TiO2) is examined in detail. Both the experimental data and theoretical calculations are combined to achieve the feast. The experimental results detected a major H-abstraction (≥87.18%) and minor OH-addition (≤12.82%) pathways for the OH-initiated heterogeneous oxidation of three xylenes on TiO2 under ultraviolet (UV) irradiation. Theoretical calculations demonstrated favorable H-abstraction on methyl group of xylenes by surface OH with large exothermic energies, because of the reason that their methyl group rather than the phenyl ring is more occupied by TiO2 via hydrogen bonding. Furthermore, the particle monitor and acute risk assessment results indicated that the H-abstraction products significantly enhance the formation of particulate matter and health risk to human beings. Taken together, these results indicate that the atmospheric oxidation mechanism of xylenes is altered in the presence of mineral particles, highlighting the necessity to re-evaluate its implication in the environment and human health. To study the migration characteristics of the heavy metals Cu and Zn carried by snowmelt water infiltrating soil during snowmelt periods and the regulation of this process by biochar, field experiments were carried out in which the variation in the Cu and Zn contents in soils on bare land (S1) and in soils with biochar coverage (S2) were analysed before snowfall and during snowmelt periods, and the degree of Cu and Zn pollution was determined on the basis of the enrichment factor (EF) and index of geoaccumulation (Igeo). The migration characteristics of Cu and Zn in soil were studied by combining the migration coefficient and leaching ratio. During the snowmelt period, the use of biochar reduced the migration coefficients of Cu and Zn carried by snowmelt water in shallow soil. The transport coefficients (Tj) of Cu and Zn in shallow soil (0-30 cm) in the S2 treatment were 0.89 and 0.81, respectively, lower than those in the S1 treatment. In addition, during the snowmelt period, the leaching ratios (Cij) of Cu and Zn in the 0-10 cm soil layer of the S2 treatment were 0.22 and 0.24 less than those of the S1 treatment, the index of geoaccumulation (Igeo) was 0.52 and 0.23 less, and the enrichment factor (EF) was 1.20 and 0.09 less, respectively. This study provides practical and theoretical guidance for future research on soil heavy metal pollution mitigation. The hormetic, biphasic dose response, is highly generalizable, being independent of biological model, level of biological organization, endpoint, inducing agent, and mechanisms. It plays a significant role in mediating both constitutive and adaptable responses in essentially all cells and organisms. The present paper provides both a historical overview of the origin of the hormetic concept in the biological and biomedical sciences, and its potential role in ecology, evolution, and development. These integrative findings provide a broad scientific framework to better understand complex evolutionary-based selection strategies, affecting survival, lifespan, fecundity, learning/memory, tissue repair, reproduction and cooperation, and developmental processes, and offering resilience in the presence of numerous challenges. Biodegradable chelators (BCs) are promising substitutes for conventional washing agents in the remediation of heavy metal contaminated soil with strong complexing ability and less cost. However, great challenges for the applications of BC-assisted washing still exist, such as the assessment of the factor affecting the efficiency of metal removal and the unclear of the metal removal mechanism. Batch washing was therefore explored to evaluate the potential for four BCs for removing Cd, Pb, and Zn from polluted soils. The soil spectroscopic characteristics before and after washing were also investigated. The results demonstrated that iminodisuccinic acid (ISA) and glutamate-N, N-diacetic acid (GLDA) were an appealing alternative to commonly used non-biodegradable ethylenediaminetetraacetic acid, but glucomonocarbonic acid (GCA) and polyaspartic acid (PASP) were less efficient. Optimal parameters of BCs were determined to be a concentration of 50 mmol L-1, a pH of 5.0, a contact time of 120 min, and a solid/liquid ratio of 15, considering metal removal efficiencies and the suitable cost.