The carbon stocks (Corg stocks) in mangrove sediments and the distribution and source changes of sedimented organic matter in Qinglan Bay are not understood as the mangrove forests decrease. In this ...paper, we collected two sediment cores in the interior mangrove and 37 surface sediment samples from mangrove-fringe, tidal flat and subtidal habitats and then analysed the total organic carbon (TOC), total nitrogen (TN), and the stable organic carbon isotope (δ13C) and nitrogen isotope (δ15N) in the sediment samples to obtain the organic matter sources and carbon stocks in two different mangrove sediment cores from Qinglan Bay. The δ13C and TOC/TN values showed that mangrove plants and algae were the main sources of organic matter. Relatively high contributions of mangrove plants (>50 %) were distributed in the mangrove areas in Wenchang estuary, the northern region of Bamen Bay and the eastern side of the Qinglan tidal inlet. The enriched δ15N values might be related to anthropogenic nutrient inputs, including increased aquaculture wastewater, human sewage and ship wastewater. The Corg stocks in cores Z02 and Z03 were 357.79 Mg C ha−1 and 265.78 Mg C ha−1, respectively. This Corg stock difference might have been related to the salinity and the benthos activities. The high Corg stock values measured in Qinglan Bay were caused by the mangrove maturity and stand age. The total Corg storage of the mangrove ecosystem in Qinglan Bay was estimated to be approximately 263.93 Gg C. This study contributes to organic carbon stocks and sources of sedimented organic matter in global mangroves.
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•Mangrove plants and algae are the main sources in Qinglan Bay sediments.•High contributions of mangrove plants were distributed in the mangrove area.•Enriched δ15N values might be related to anthropogenic nutrient inputs.•The Corg stock differences might be related to the salinity and benthos activities.•The high Corg stocks were caused by the maturity of mangroves and the stand age.
Membrane technology has been widely used to treat wastewater from a variety of industries, but it also results in a large amount of concentrated wastewater containing organic pollutants after ...membrane treatment, which is challenging to decompose. Here in this work, a series of perovskite SrFexZr1-xO3-δ catalysts were prepared via a modified co-precipitation method and evaluated for catalytic ozone oxidative degradation of m-cresol. An artificial neural intelligence networks (ANN) model was employed to train the experimental data to optimize the preparation parameters of catalysts, with SrFe0.13Zr0.87O3-δ being the optimal catalysts. The resultant catalysts before and after reduction were then thoroughly characterized and tested for m-cresol degradation. It was found that the co-doping of Fe and Zr at the B-site and the improvement of oxygen vacancies and oxygen active species by reduction dramatically increased TOC removal rates up to 5 times compared with ozone alone, with the conversion rate of m-cresol reaching 100%. We also proposed a possible mechanism for m-cresol degradation via investigating the intermediates using GC-MS, and confirmed the good versatility of the reduced SrFe0.13Zr0.87O3-δ catalyst to remove other common organic pollutants in concentrated wastewater. This work demonstrates new prospects for the use of perovskite materials in wastewater treatment.
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•Preparation of perovskite SrFexZr1-xO3-δ catalysts using a modified co-precipitation method.•Cross-validation using neural network models (AI) and experimental data to optimize catalysts-.•Reduction treatment improves SrFe0.13Zr0.87O3-δ oxygen vacancies and catalytic activity.•SrFe0.13Zr0.87O3-δ generates reactive radicals to improve the reaction rate of CWOO.
Shale CO2 wettability is a key factor which determines the structural trapping capacity of a caprock. However, the influence of shale‐total organic content (TOC) on wettability (and thus on storage ...potential) has not been evaluated despite the fact that naturally occurring shale formations can vary dramatically in TOC, and that even minute TOC strongly affects storage capacities and containment security. Thus, there is a serious lack of understanding in terms of how shale, with varying organic content, performs in a CO2 geo‐storage context. We demonstrate here that CO2‐wettability scales with shale‐TOC at storage conditions, and we propose that if TOC is low, shale is suitable as a caprock in conventional structural trapping scenarios, while if TOC is ultrahigh to medium, the shale itself is suitable as a storage medium (via adsorption trapping after CO2 injection through fractured horizontal wells).
Key Points
Shale total organic content (TOC) scales with CO2 wettability
Low TOC shales are water‐wet at storage conditions (good for structural trapping)
Organic‐rich shales are CO2‐wet at storage conditions (good for adsorption trapping)
The performance of a pilot-scale boron-doped diamond (BDD) reactor through a numerical analysis of reaction rate parameters and enhanced mass transfer has been investigated. The main objective of ...this research is to evaluate the efficiency of the reactor in mineralizing and degrading caffeine as an emerging contaminant. Based on the kinetic mechanisms and mass transport correlations reported in the literature, two reaction rate kinetic models for caffeine degradation are proposed and analyzed. The models consider different electrolytes (NaCl and Na2SO4) and applied current densities. The kinetic fitting process utilizes the gradient-maximal electrochemical approach, together with orthogonal placement methods, fourth-order Runge-Kutta (RK4) methods, and Nelder & Mead methods for optimization of kinetic parameters and spatial discretization of the material balance. Experimental data obtained from a factorial design with four factors and two levels (24) validate the proposed kinetic models. Caffeine degradation is achieved with NaCl and Na2SO4 electrolytes at concentrations of 60 ppm and 100 ppm, respectively. The corresponding applied loads are 1.5 AhL−1 and 3 AhL−1. Na2SO4 exhibits superior performance with a total organic carbon (TOC) removal efficiency of 99.13%, while NaCl achieves 31.47% mineralization. The behavior of caffeine degradation under the operational and scale conditions demonstrates that NaCl, as a support electrolyte, enables controlled charge transfer (current density) during the degradation process. In contrast, Na2SO4 as a support electrolyte introduces a mixed control of charge and mass transfer. The pilot-scale kinetic parameters obtained in this study provide valuable insights into the support electrolyte dynamics and current density dynamics in BDD-based Electrooxidation (EO) systems, particularly in complex matrix applications. Furthermore, the observed electrical consumption supports the potential application of EO as a viable technology for industrial-scale tertiary wastewater treatment, specifically for caffeine removal.
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•Degradation and mineralization of emerging contaminants with anodic oxidation.•Analysis of the electrolyte support in the speed of reaction in BDD.•Oxidizing species in anodic electrooxidation with BDD at pilot scale.•Calculation of mass transfer depending on the type of electrolyte.•Process control by mass or current transfer in anodic oxidation.
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•Lab-scaled photocatalyst (TiO2) was prepared by the solution combustion method.•Synthesize photocatalyst characterized by FESEM, XRD and XPS.•BOD5/COD (0.59±0.089) and BOD5/TOC ...(1.74±0.03) were improved by photocatalytic degradation.•Maximum removal efficiency obtained was 98.43±1.31% through integrated system.•The performance of PBBR was analyzed in terms of % REP, PLR and % ECPR.
Integratingphotocatalysisand biodegradation has shown great potential in wastewater treatment technology. In this study, the degradation of p-cresol in water has been investigated through an integrated system comprising of photocatalytic and packed bed biofilm reactor (PBBR). In the photocatalytic reactor, the biodegradability index (BOD5/COD, BOD5/TOC) of the p-cresol solution was first shown to increase (from 0.098±0.023 to 0.59±0.089 for BOD5/COD and from 0.27±0.030 to 1.74±0.03 for BOD5/TOC). The pseudo-first-order rate constant (kap) was found to be 0.011 min−1. The % removal of the integrated system was found to be 98.43±1.31% at an initial concentration of 700 mg L-1 and residence time of 120 h, which was significantly higher than the PBBR operated alone (34.82±2.62%) under optimized conditions (pH 7.0 and T = 32±2 °C). Using an integrated approach, the efficient removal of p-cresol opens novel future perspectives for catalytic degradation using chemical oxidation.
RESUMO Objetivo Identificar e mapear as evidências disponíveis sobre a composição da Microbiota Intestinal em indivíduos com Transtorno Obsessivo-Compulsivo e seus transtornos relacionados. Métodos ...https://osf.io/bd2ns Resultados Espera-se encontrar uma relação entre a composição da Microbiota Intestinal, em quantidade e tipo de espécies, e os sintomas do TOC e dos seus Transtornos relacionados. Conclusão Esta será a primeira scoping review que procura investigar a relação entre a microbiota intestinal e o Transtorno Obsessivo-Compulsivo e Transtornos relacionados. A publicação prévia deste protocolo de revisão irá colaborar para um melhor planejamento do estudo e divulgação da investigação junto da comunidade científica.
ABSTRACT Objective To identify and map the available evidence regarding Gut Microbiota composition in individuals with obsessive-compulsive disorder and its related Disorders. Methods https://osf.io/bd2ns Results It’s hoped to find a relationship between the composition of the gut microbiota, in terms of quantity and type of species, and the symptoms of OCD and its related disorders. Conclusion This will be the first scoping review that seeks to investigate the relationship between Gut Microbiota and Obsessive-Compulsive Disorder and its related disorders. The previous publication of this review protocol will collaborate for a better planning of the study and dissemination of the research to the scientific community.
Concentrations and distribution characteristics of organophosphate esters (OPEs) in surface sediment samples were analyzed and discussed for the first time in the open Bohai Sea (BS) and Yellow Sea ...(YS). Three halogenated OPEs tris-(2-chloroethyl) phosphate (TCEP), tris-(1-chloro-2-propyl) phosphate (TCPP), and tris-(1,3-dichloro-2-propyl) phosphate (TDCPP) and five non-halogenated OPEs tri-isobutyl phosphate (TiBP), tri-n-butyl phosphate (TnBP), tripentyl phosphate (TPeP), triphenyl phosphate (TPhP) and tris-(2-ethylhexyl) phosphate (TEHP) were detected in this region. The concentrations of eight OPEs in total (Σ8OPEs) ranged from 83 to 4552pgg−1dry weight (dw). The halogenated OPEs showed higher abundances than the non-halogenated ones did, with TCEP, TCPP, and TEHP the main compounds. Generally, concentrations of OPEs in the BS were higher than those in the YS. Riverine input (mainly the Changjiang Diluted Water (CDW)) and deposition effect in the mud areas might have influenced the spatial distributions of OPEs. Correlation between OPE concentrations and total organic carbon (TOC) indicated TOC was an effective indicator for the distribution of OPEs. Inventory analysis of OPEs implied that sea sediment might not be the major reservoir of these compounds.
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•Eight OPEs were widely detected in the sediment of the Bohai and Yellow Seas.•TCEP and TEHP were the most dominant OPEs.•High levels of OPEs were found in the Bohai Sea than those in the Yellow Sea.•OPEs showed a positive correlation with TOC.•Riverine discharge and hydrodynamic parameters influence the spatial distributions of OPEs.
Carbon isotopic compositions of organic matter (δ13Corg) provide critical information about changes in the global carbon cycle through Earth's history. However, several biotic and abiotic processes ...occurring after sediment deposition may overprint the original geochemical signals, complicating their paleoenvironmental interpretation. Here, we report multiple large and rapid δ13Corg swings (ranging from −30.8‰ to −23.3‰) from three Paleozoic drill cores in the Ordos Basin, Northwest China, which may reflect different organic contributions related to lithology. As a potentially important organic matter source, migrated hydrocarbons may substantially alter the original δ13Corg and total organic carbon contents (TOC), and their oxidation may contribute to forming 13C- and 18O-depelted carbonate cements in siliciclastic-dominated strata at depth. Cross-plots of δ13Corg and TOC from samples of the three drill cores all show similar hyperbolic trends that are well simulated using Rayleigh fractionation and a two-component mixing model, thus providing potential criteria for identifying the reservoir and the related hydrocarbon source in oil exploration. Our data call for a critical reassessment of the δ13Corg records of sedimentary rocks if hydrocarbon redistribution or mixing of organic sources is suspected to have occurred during the burial history.
•Large δ13Corg swings are revealed in Paleozoic drill cores from the Ordos Basin.•Cross-plots of δ13Corg and TOC show hydrocarbon redistribution and mixing.•A critical reassessment of the δ13Corg records of sedimentary rocks is needed.
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