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Lacustrine sedimentary formations potentially contain hydrocarbons. The lacustrine sedimentary rocks of the Ziliujung and Xintiangou Formations have been investigated for their hydrocarbon potential using low-pressure nitrogen adsorption (LP-N2A), low-field nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), total organic carbon (TOC), rock-eval pyrolysis (Rock-Eval), gas chromatography (GC), gas chromatography–mass spectrometry (GC–MS), X-ray fluorescence spectrometry (XRF), and inductively coupled plasma mass spectrometry (ICP-MS). The results show that the normalized difference of the pore parameters between the two formations is less than 10%, and the pores are mainly slit-like mesopores with high porosity. Macropores and micropores are often developed in the quartz skeleton, while mesopores often occur among organic matter, clay minerals, carbonate minerals, and pyrite particles. The organic matter abundance of the Ziliujing Formation is relatively high. Additionally, the organic matter types of the two formations are mainly type II and type III, and the sources of the organic matter are plankton and bacteria which have reached the mature gas production stage. The palaeoenvironmental differences between the depositional periods of the two formations lie within 10% of each other. The warm and humid climate promotes the development of quartz minerals to further enhance the proportion of both micropores and macropores, and the clay minerals, carbonate minerals, and pyrite carried in the terrigenous detritus are closely associated with the total organic carbon (TOC), which promotes the development of mesopores to enhance the porosity. The reservoir, organic matter, and palaeoenvironmental characteristics of fine-grained sedimentary rocks in the two formations are similar, and both of them have good potential for development. The above results provide a basic geological theoretical basis for unconventional oil and gas exploration in the northeastern margin of the Sichuan Basin. [ABSTRACT FROM AUTHOR]

The purpose of this article is to systematically examine the literature around Curriculum Based Measurement in Writing (CBM‐W) for English learners (ELs) in English. We reviewed the literature to identify published research studies examining CBM‐W that disaggregated data for ELs. We identified six published studies examining the technical adequacy of CBM‐W specifically for ELs. The studies examined a variety of types of CBM‐W across diverse populations of ELs but all were restricted to stage 1 of CBM research. Only one study included ELs participating in a bilingual model of instruction and their findings contrasted with other studies including ELs participating in English‐only models of instruction. While there is emerging evidence of the technical adequacy for ELs across a variety of CBM‐W types for screening purposes, there is little evidence to currently support their use for progress‐monitoring or for ELs participating in bilingual models of instruction. Suggestions for current practice and future research are described. Practitioner Points: School psychologists should emphasize writing development and consider including Curriculum Based Measurement in Writing (CBM‐W).School psychologists should use their school's CBM‐W assessment data to create local norms and rates of growth according to English Language Proficiency for their English learners (ELs) as well as reference published norms and rates of growth.School psychologists should use more than just CBM‐W data to drive high‐stakes and instructional decisions for ELs. [ABSTRACT FROM AUTHOR]

A new approach is presented in this paper for the dynamic modeling of the chemical and isotopic evolution of C1–3 during the hydrocarbon generation process. Based on systematic data obtained from published papers for the pyrolysis of various hydrocarbon sources (type I kerogen/source rock, type II kerogen/source rock, type III kerogen/source rock, crude oil, and asphalt, etc.), the empirical evolution framework of the chemical and isotopic composition of C1–3 during the hydrocarbon generation process was built. Although the empirical framework was built only by fitting a large amount of pyrolysis data, the chemical and isotopic composition of C1–3 derived from the pyrolysis experiments all follow evolution laws, convincing us that it is applicable to the thermal evolution process of various hydrocarbon sources. Based on the simplified formula of the isotopic composition of mixed natural gas at different maturities (δ13Cmixed), δ13Cmixed = X × n i A × δ 13 C i A + Y × n i B × δ 13 C i B X × n i A + Y × n i B , it can be derived that the cumulative isotopic composition of alkane generated in a certain maturity interval can be expressed by the integral of the product of the instantaneous isotopic composition and instantaneous yield at a certain maturity point, and then divided by the cumulative yield of alkane generated in the corresponding maturity interval. Thus, the cumulative isotopic composition (A(X)), cumulative yield (B(X)), instantaneous isotope (C(X)), and instantaneous yield (D(x)) in the dynamic model, comply with the following formula during the maturity interval of (X0~X). A(X) = ∫ X 0 X C X × D X d x B (X) , where A(X) and B(X) can be obtained by the fitting of pyrolysis data, and D(x) can also be obtained from the derivation of B(X). The dynamic model was applied on the pyrolysis data of Pingliang Shale to illustrate the quantitative evolution of the cumulative yield, instantaneous yield, cumulative isotope, and instantaneous isotope of C1–3 with increasing maturity. The dynamic model can quantify the yield of methane, ethane, and propane, as well as δ13C1, δ13C2, and δ13C3, respectively, during the hydrocarbon generation process. This model is of great significance for evaluating the natural gas resources of hydrocarbon source rock of different maturities and for identifying the origin and evolutionary process of hydrocarbons by chemical and isotopic data. Moreover, this model provides an approach to study the dynamic evolution of the isotope series of C1–3 (including reversed isotopic series), which is promising for revealing the mechanism responsible for isotopic reversal when combined with post-generation studies. [ABSTRACT FROM AUTHOR]

This scoping review systematically evaluates the use of systemic antibiotics in treating acute irreversible pulpitis, integrating clinical practice patterns with recent molecular insights. We analyzed clinical evidence on antibiotic prescription trends among dental professionals and examined molecular research advancements in relation to pulpitis. This review is intended to bridge the gap between clinical practice and molecular research, guiding more evidence-based approaches to treating acute irreversible pulpitis. Electronic databases were searched for relevant articles published in English based on the objective of the review. A second search using all identified keywords and index terms was undertaken across all the included databases. In addition, a reference list of identified articles was searched. Studies including original research, systematic reviews, meta-analyses, clinical trials, and observational and retrospective studies, all written in English and published from 2010 onwards, were included, and an analysis of the text words contained in the titles and abstracts of the retrieved papers and of the index terms used to describe the articles was performed. A total of N = 53 articles were selected. Altogether, N = 43 (76.79%) articles were cross-sectional studies, N = 4 (11.11%) were systematic reviews, and N = 3 (5.36%) were guidelines. The most frequent level of evidence was level VI (N = 43 (76.79%). The mean percentage of dentists who prescribed antibiotics to treat acute irreversible pulpitis was 23.89 ± 23.74% (range: 0.05–75.7). Similarly, for specialists, it was 22.41 ± 15.64 (range 2.2–50.4), and the percentage for undergraduates was 17.52 ± 20.59 (range 0–62.6). The significant developments in research models for pulpitis research and the characterisation of biomarkers have led to better management strategies. Concurrently, significant advancements in molecular research provide new understandings of pulpitis, suggesting alternative therapeutic approaches. Although there are guidelines available, increased rates of antibiotic prescription are still prevalent around the globe. [ABSTRACT FROM AUTHOR]

In this work, hydrogen peroxide (H 2 O 2) is produced using an optimized electrochemical cell equipped with a gas diffusion electrode (GDE) as cathode, reaching efficiencies as high as 20.1%, when operating in a single compartment configuration, which increases up to the range 50–60, when a proton exchange membrane is used to separate the anodic and cathodic compartments, pointing out the great significance of the anodic oxidation of H 2 O 2 and the scavenging effects of the oxidants produced on the anode surface. As compared to previous materials tested, the GDE implemented in this cell underwent a more sustainable manufacturing procedure and exhibited an outstanding performance. The H 2 O 2 produced electrochemically is dosed to the real leachate of an industrial dump, strongly polluted with derivatives of lindane. This waste is associated to the operation of a large facility in the seventies and contains different isomers of hexachlorocyclohexane and other chlorinated hydrocarbons, produced during the ageing of the dump. Effects of the addition of iron (II) sulfate salts and irradiation of UVC were also evaluated. All electrochemically-assisted technologies evaluated (named as chemical (EACO), Fenton (EAFO), photolysis (EAPO) and photo-Fenton (EAPFO) oxidations) were able to successfully remove the pollutants, although with important differences in the efficiencies reached. Results demonstrate that EACO, that is, oxidation by molecular H 2 O 2 is the most effective treatment for the treatment of this type of wastes, pointing out that activation of H 2 O 2 to hydroxyl radicals, either by electrochemically assisted Fenton or photolysis is not positive for this waste. As well, among the different pollutants contained in the raw waste, removal of hexachlorocyclohexane (HCHs) and non-chlorinated volatile organic compounds (VOCs) stands out (both groups being the primary species contained in the wastes). These results are very important not only because of the outstanding productions of H 2 O 2 reached with the novel approach of electrochemical cell used, but also because of the implications of the mechanistic understanding of the attack of H 2 O 2 species in the design of a full-scale application to remediate this real important problem. [Display omitted] • Improved production of H 2 O 2 with a novel GDE and cell. • H 2 O 2 is produced with efficiencies over 20% in non-divided configurations. • Improved efficiency when using divided cells, with values as high as 50–60%. • Several electrochemical H 2 O 2 based technologies suitable for degradation wastes. • Unexpectedly H 2 O 2 more efficient that hydroxyl radicals in destroying CHCs. [ABSTRACT FROM AUTHOR]

This study describes the design and upscaling of an on‐site regenerable adsorbent fixed bed of Fe‐loaded MFI zeolite for removal of chlorinated hydrocarbons (CHCs) from contaminated groundwater from laboratory studies to pilot scale. The zeolite has an excellent adsorption performance for the hydrophilic CHCs and can be regenerated on‐site by flushing with H2O2 to degrade adsorbed contaminants by a catalytic Fenton‐like reaction. In the pilot test, the Fe‐zeolite (30 kg) maintained its performance over treatment of 1470 m3 of groundwater in 12 adsorption/regeneration cycles. [ABSTRACT FROM AUTHOR]

Resting cell batch kinetic studies were performed to evaluate the alcohol-dependent cometabolic degradation of chlorinated aliphatic hydrocarbons (CAHs) and 1,4-dioxane (1,4-D) by Rhodococcus rhodochrous strain ATCC 21198. This strain grew on diverse alcohols, organic acids, esters, and other organic compounds. Only growth on 2-butanol resulted in labeling of monooxygenase enzymes and the ability to oxidize propylene, the cylic ether 1,4-D, and its close structural analog tetrahydrofuran. In single compound rate tests, 2-butanol-grown cells exhibited faster degradation rates for less chlorinated compounds. The rates of degradation are ranked as follows from high to low: vinyl chloride > cis-dichloroethene (cis-DCE) >1,1-dichoroethane >1,1-dichoroethene (1,1-DCE) >1,4-D > 1,1,1-trichoroethane (1,1,1-TCA) >1,1,2-trichoroethene. All rates were significantly lower than isobutane-grown cells. 2-Butanol-grown cells exhibited a lag period before cometabolic degradation of most CAHs, including cis-DCE; however, production of cis-1,2-dichloro-1,2-epoxyethane (cis-DCE epoxide) was detected with no lag. Cells grown on 1-butanol, 2-butanol, or 2-ethyl-1-butanol also cometabolically degraded 1,4-D and various CAHs. However, compared to cells grown on 1-butanol or 2-ethyl-1-butanol, cells grown on 2-butanol had a larger transformation capacity and faster degradation rates and were able to fully degrade (>99% removal) a mixture of 1,4-D, cis-DCE, and 1,1,1-TCA. With CAH mixtures, alcohol-grown cells degraded cis-DCE faster than both 1,1,1-TCA and 1,4-D. sec-Butyl-acetate (sBA) was demonstrated as a potential slow-release substrate that hydrolyzes to yield 2-butanol and acetate. Cells grown on this ester degraded a mixture of 1,1,1-TCA and 1,4-D at rates faster than 2-butanol-grown cells. The cometabolic transformation of 1,1,1-TCA and 1,4-D was also observed in reactors where growth occurred with sBA as the growth substrate. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is an endocrine system and metabolic disorder caused by defects in insulin secretion and action. Syzygium cumini (L.) Skeels (Myrtaceae) are often used in anti-diabetic medicine due to their high polyphenol contents. This study aims to provide a comprehensive review of the role of phytochemical compounds in S cumini as traditional antidiabetic medicinal plants. The review covers related articles on antidiabetic AND S cumini AND phytochemicals OR bioactive compounds. The examined articles were published from 2001 to January 2023. Pubmed, Science Direct, Scopus, and Google Scholar were utilized as the bibliographic databases in this systematic search. The inclusion criteria include articles written in English that describe experimental research, clinical trials, and randomized studies and articles containing phytochemical content profiling. The exclusion criteria were other types of reports such as literature reviews, conference articles, theses, dissertations, and cases that were irrelevant to the topic. The reporting item guidelines used for references in this review were the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Center for Systematic Reviews for Laboratory Animal Experiments (SYRCLE) risk of bias (RoB) tool. By the systematic compensation used, 15 articles that meet the requirements were obtained and were further reviewed thoroughly. Seeds, leaves, and bark of plant parts were reported to be non-toxic in acute experiments on mice or rats. S. cumini contains flavonol glycosides, especially myricetin, myricitrin, quercetin, and kaempferol; phenolics, such as ellagic acid, tannins, and gallic acid; alkaloids; and saponins. These compounds contributions to the overall anti-diabetic activity were discussed by covering an increase of insulin sensitivity, secretion, and usage of glucose in tissues; thereby reducing insulin resistance, oxidative stress, gluconeogenesis, and absorption of carbohydrates and sucrose. In conclusion, the review confirmed that the compounds of S. cumini have a potential for treating diabetes mellitus. Specifically, the seeds and leaves of S. cumini have a high potential as antidiabetic herbal product, and thus making it crucial to find the research gap to support the development of this herbal compound by establishing preclinical and clinical trials and reliable analytical methods for phytochemical profiling. [ABSTRACT FROM AUTHOR]

Simple lanthanide cyclopentadienyl (Cp) complexes can photochemically cleave the sp3 carbon–chlorine bond of unactivated chlorinated hydrocarbons including polyvinyl chloride (PVC). The excited state lifetimes of these simple complexes are among the longest observed for cerium complexes (175 ns for [(CpMe4)2Ce(μ-Cl)]2) and the light absorption by the Cp ligand is efficient, so photocatalytic reactivity is enhanced for cerium and now also made possible for neighboring, normally photoinactive, lanthanide congeners. [ABSTRACT FROM AUTHOR]

[Display omitted] Chlorinated volatile organic compounds (CVOCs) are a recalcitrant class of air pollutants, and the strongly oxidizing reactive oxygen species (ROS) generated in advanced oxidation processes (AOPs) are promising to degrade them. In this study, a FeOCl-loaded biomass-derived activated carbon (BAC) has been used as an adsorbent for accumulating CVOCs and catalyst for activating H 2 O 2 to construct a wet scrubber for the removal of airborne CVOCs. In addition to well-developed micropores, the BAC has macropores mimicking those of biostructures, which allows CVOCs to diffuse easily to its adsorption sites and catalytic sites. Probe experiments have revealed HO• to be the dominant ROS in the FeOCl/BAC + H 2 O 2 system. The wet scrubber performs well at pH 3 and H 2 O 2 concentrations as low as a few mM. It is capable of removing over 90% of dichloroethane, trichloroethylene, dichloromethane and chlorobenzene from air. By applying pulsed dosing or continuous dosing to replenish H 2 O 2 to maintain its appropriate concentration, the system achieves good long-term efficiency. A dichloroethane degradation pathway is proposed based on the analysis of intermediates. This work may provide inspiration for the design of catalyst exploiting the inherent structure of biomass for catalytic wet oxidation of CVOCs or other contaminants. [ABSTRACT FROM AUTHOR]

It is of much interest to study the heavy hydrocarbon impact on the phase behavior of hydrocarbons. Using a method of the precision adiabatic calorimetry the phase equilibria in quaternary mixtures of methane, propane, octane, and nonane have been studied. The phase diagrams for investigated mixtures have been plotted based on the experimental data. The phase transitions were localized by the finite discontinuities in temperature derivatives of the thermodynamic potentials. The heat capacity, internal energy, pressure, and temperature derivative of pressure at constant volume were measured in the range 170–320 K, up to 40 MPa. Quaternary mixtures as quasi-binary mixtures are presented. The first quasi-component of the quasi-binary mixture is the binary mixture with the constant methane/propane ratio. The second quasi-component of the quasi-binary mixture is the binary mixture of octane and nonane. Investigated hydrocarbon system is the combination of the simple hydrocarbon mixtures for the low concentration of octane and nonane. In the earlier papers we presented the simple hydrocarbon mixtures for the low concentration of octane, nonane, and decane, and quaternary mixtures of methane, propane, octane, and decane for the low concentration of octane and decane, which are the combination of the simple hydrocarbon mixtures for the low concentration of octane and decane. Our investigations show that quaternary hydrocarbon mixture for the low concentration of octane and nonane as well as the simple hydrocarbon mixtures for the low concentration of octane, nonane, and decane split into three phases, the macrophase composed of methane, propane, octane, and nonane, and two microphases formed by octane and nonane. In this system octane and nonane dissolved in the macrophase partly. Besides, the heavy components provoke a split of the liquid part of the quaternary mixture into two liquid phases. [ABSTRACT FROM AUTHOR]

This account summarizes our recent efforts in the enantioselective organocatalytic synthesis of chiral halogenated compounds. The enantioselective α‐halogenation of aldehydes, decarboxylative chlorination of β‐keto acids, and enantioselective C−C bond formation at the trifluoromethylated prochiral carbon to yield the corresponding organohalides with chlorinated, fluorinated, or trifluoromethylated chiral stereogenic centers are discussed. We applied common organocatalysts, such as Jørgensen‐Hayashi catalyst and cinchona alkaloid‐derivatived catalyst, and developed novel chiral amine catalysts for these reactions. This account also discusses stereospecific derivatizations of the resulting chiral halogenated compounds via nucleophilic substitution. Thus, we synthesized many novel chiral compounds that have not been reported, even as racemates. [ABSTRACT FROM AUTHOR]

This work presents the synthesis and modification of cost-effective groundnut shell-based carbon sorbent and its utilization to extract chlorinated hydrocarbons from wastewater. The synthesized carbon sorbent was doped with nitrogen by treatment with melamine and further decorated with different weight percent of nickel by solid-state impregnation to achieve nickel-decorated nitrogen-doped carbon sorbents. The physicochemical properties of the sorbents were studied using Brunauer–Emmett–Teller, Fourier transform infrared spectroscopy, and field-emission scanning electron microscope. Each sorbent was then sealed into a polypropylene membrane like a tea bag and utilized to extract the chlorinated hydrocarbons from an aqueous sample and quantified using GC–MS. All the extraction-related parameters were optimized. The overall process presented a wide linear range (10–800 ng mL−1) with a coefficient of correlation between 0.9875 and 0.9943. The limit of detection (1.85–3.45 ng mL−1) and reproducibility (1.2–11%) were observed with relative recovery from the wastewater sample in the range of 85.4 to 114%. [ABSTRACT FROM AUTHOR]

The peracid oxidation of hydrocarbons in chlorinated solvents is a low yielding and poorly selective process. Through a combination of DFT calculations, spectroscopic studies, and kinetic measurement it is shown that the origin of this is electronic in nature and can be influenced through the addition of hydrogen bond donors (HBD) and hydrogen bond acceptors (HBA). Performing the reaction of a cycloalkane with mCPBA in a fluorinated alcohol solvent such as nonafluoro‐tert‐butanol (NFTB) or hexafluoroisopropanol (HFIP), which act as strong HBD and poor HBA, leads to significantly higher yields and selectivities being observed for the alcohol product. Application of the optimised reaction conditions allows for the selective oxidation of both cyclic and linear alkane substrates delivering the corresponding alcohol in up to 86 % yield. The transformation shows selectivity for tertiary centres over secondary centres and the oxidation of secondary centres is strongly influenced by stereoelectronic effects. Primary centres are not oxidised by this method. A simple computational model developed to understand this transformation provides a powerful tool to reliably predict the influence of substitution and functionality on reaction outcome. [ABSTRACT FROM AUTHOR]

This study investigates the use of 10‐(4‐butoxyphenyl)‐10H‐phenothiazine (PTZ), a phenothiazine‐based molecule, for detecting chloroform and other chlorinated hydrocarbons (CHCs). Upon exposure to these compounds to the phenothiazine‐dervitive in presence light, a significant change in emission occurs, enabling naked‐eye detection. The visual detection range of this phenothiazine derivative extends down to concentrations as low as 5 ppm. We demonstrate the one‐time use of thin‐layer chromatography paper (TLC) sensors and glass‐based sensors for on‐site detection of chlorinated hydrocarbons using a light source such as sunlight, UV‐lamp, or a solar box. Our findings suggest that this phenothiazine‐derivative has potential as a simple, low‐cost, and effective sensing platform for chlorinated solvents, with practical applications in environmental monitoring and industrial safety. Furthermore, our results provide insights into the development of molecular sensors for detecting chlorinated hydrocarbons. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations including umbrella sampling free energy calculations are used to examine the structure, thermodynamics, and dynamics that accompany the transfer of the classical hydronium ion (H3O+) across the water/1,2-dichloroethane interface. The calculated free energy of transfer (17 ± 1 kcal/mol) is somewhat larger than the experimental value (14 kcal/mol). A detailed examination of the hydration structure is provided, and several dynamical properties as a function of the distance along the interface normal are calculated. In particular, it is shown that the hydronium ion is transferred as an Eigen species, and while the three hydration shell water molecules' average structure is conserved during the transfer, they may be exchanged with nearby water molecules with a rate that decreases as the ion enters the organic phase. [ABSTRACT FROM AUTHOR]

The United States Environmental Protection Agency (EPA) regulates chemical manufacture, import, processing, distribution, use, and disposal under the 2016 amended Toxic Substances Control Act (TSCA) for the purposes of protecting the public and sensitive populations—including workers—from chemical exposure risk. The publication of several TSCA risk evaluations provided a unique opportunity to evaluate the evolving regulatory approach for assessing the dermal exposure pathway in occupational settings. In this analysis, the occupational dermal exposure assessment methods employed in several TSCA risk evaluations were assessed. Specifically, a methodology review was conducted for the occupational dermal scenarios of manufacturing and feedstock use in the risk evaluations of three chlorinated organic chemicals: trichloroethylene, carbon tetrachloride, and perchloroethylene. Additionally, alternative exposure estimates were generated using the exposure model IH SkinPermTM. The review and alternative exposure analyses indicate that the current TSCA modeling approach may generate total dermal absorbed doses for chlorinated chemical manufacturing and feedstock use scenarios that are 2- to 20-fold higher than those generated by IH SkinPerm. Best-practice recommendations developed in the methodology review support a tiered, integrated approach to dermal exposure assessment that emphasizes collecting qualitative data; employing validated, peer-reviewed models that align with current industrial practices; and gathering empirical sampling data where needed. Collaboration among industry, EPA, and other stakeholders to share information and develop a standard approach to exposure assessment under TSCA would improve the methodological rigor of, and increase confidence in, the risk evaluation results. [ABSTRACT FROM AUTHOR]

Thermodynamic characteristics of adsorption of hydrocarbon molecules with the linear, planar, and cage structures and their isostructural chlorine derivatives were determined by equilibrium gas adsorption chromatography on columns with graphitized thermal carbon black in the range of the lowest concentrations of the adsorbate in the gas phase (Henry's region). When the planar molecules of methylbenzenes and chlorobenzenes are adsorbed, the methyl groups and chlorine atoms, which are close in polarizability, make the same contribution to the heat of adsorption. However, in the adsorption of bulky molecules, the replacement of the methyl groups by chlorine atoms results in an average increase of 4 kJ mol−1 for the heats of adsorption. A possible reason for the differences in the heats of adsorption of the bulky hydrocarbons and isostructural chlorine derivatives is that induction interactions R-Cl...π(graphite) are imposed on dispersion interactions characteristic of adsorption on the graphite-like adsorbents. The induction interactions developed are due to specific features of the orientation of the R-Cl polar bonds in the bulky molecules of the adsorbates relative to the planar graphite surface at the adsorption equilibrium. [ABSTRACT FROM AUTHOR]

The nonthermal plasma treatment of 1,2‐dichloroethane, 1,1,2‐trichloroethane, and 1,1,2,2‐tetrachloroethane in the liquid phase leads to the formation of unsaturated chlorine derivatives of hydrocarbons, nanostructures, and hydrogen chloride. In the case of nonthermal plasma‐induced elimination of chloroethanes, the main products are: chloroethene from 1,2‐dichloroethane, 1,1‐dichloro‐, 1,2‐dichloroethene from trichloroethane, and trichloro‐ and tetrachlorethylenes from tetrachloroethane. Solid products are presented in the form of nanoscale carbon structures—multilayer nanotubes, carbon fibers, graphene layers, and others. Quantum‐chemical calculations show that the elimination of HCl under the nonthermal plasma treatment on chloroethanes occurs intermolecularly. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen-modified zero-valent iron coated with Fe−N(C) was successfully prepared. • Properties of N(C)-mZVIbm from different N sources are relate to nitrogen species. • The effect of N/Fe, ball milling time and speed were studied on TCE dechlorination. • Fe−N(C) reactive species mitigate particle passivation in alkaline conditions. • The study provides new insights into N-modified ZVI-based remediation technology. The performance optimization of zero-valent iron (ZVI) based materials for reductive dechlorination remains challenging. After extensive research on sulfidation modification, the doping of heteroatom nitrogen (N) into ZVI for reductive dechlorination of chlorinated hydrocarbons (CHCs) becomes a new promising trend. In this study, surface modification of microscale ZVI (mZVI) was carried out by a facile ball milling method, and Fe–N(C) coated mZVI (abbreviated as N(C)-mZVIbm) synthesized from different N sources of dimethylimidazole, urea and melamine were characterized. The effects of nitrogen-to-iron ratios (N/Fe), ball milling time and speed on the reductive dechlorination of trichloroethylene (TCE) were further investigated. A series of characterization and mechanistic analysis showed that the high reactivity of N(C)-mZVIbm with melamine as nitrogen source (abbreviated as N(C)-mZVIbm(M)) was attributed to the properties and thickness of its particle passivation layer, and faster electron transfer from the reduced iron species to the surface layer. In addition, N(C)-mZVIbm(M) exhibited great performance for dechlorination at a wide pH range of 3 to 11, due to alleviated passivation of the Fe0 core under alkaline conditions by Fe–N(C). This study presents new ideas and evidences for the environmentally friendly synthesis of N-modified ZVI materials and their practical application in groundwater remediation. [ABSTRACT FROM AUTHOR]

Anaerobic biotechnology for wastewaters treatment can nowadays be considered as state of the art methods. Nonetheless, this technology exhibits certain inherent limitations when employed for industrial wastewater treatment, encompassing elevated substrate consumption, diminished electron transfer efficiency, and compromised system stability. To address the above issues, increasing interest is being given to the potential of using conductive non-biological materials, e,g., iron sulfide (FeS), as a readily accessible electron donor and electron shuttle in the biological decontamination process. In this study, Mackinawite nanoparticles (FeS NPs) were studied for their ability to serve as electron donors for p -chloronitrobenzene (p -CNB) anaerobic reduction within a coupled system. This coupled system achieved an impressive p -CNB removal efficiency of 78.3 ± 2.9% at a FeS NPs dosage of 1 mg/L, surpassing the efficiencies of 62.1 ± 1.5% of abiotic and 30.6 ± 1.6% of biotic control systems, respectively. Notably, the coupled system exhibited exclusive formation of aniline (AN), indicating the partial dechlorination of p -CNB. The improvements observed in the coupled system were attributed to the increased activity in the electron transport system (ETS), which enhanced the sludge conductivity and nitroaromatic reductases activity. The analysis of equivalent electron donors confirmed that the S2- ions dominated the anaerobic reduction of p -CNB in the coupled system. However, the anaerobic reduction of p -CNB would be adversely inhibited when the FeS NPs dosage exceeded 5 g/L. In a continuous operation, the p -CNB concentration and HRT were optimized as 125 mg/L and 40 h, respectively, resulting in an outstanding p -CNB removal efficiency exceeding 94.0% after 160 days. During the anaerobic reduction process, as contributed by the predominant bacterium of Thiobacillus with a 6.6% relative abundance, a mass of p -chloroaniline (p -CAN) and AN were generated. Additionally, Desulfomonile was emerged with abundances ranging from 0.3 to 0.7%, which was also beneficial for the reduction of p -CNB to AN. The long-term stable performance of the coupled system highlighted that anaerobic technology mediated by FeS NPs has a promising potential for the treatment of wastewater containing chlorinated nitroaromatic compounds, especially without the aid of organic co-substrates. [Display omitted] • FeS NPs as inorganic electron donor enables high p -CNB anaerobic reduction. • Interspecies mass and electron transfer was facilitated using FeS NPs as mediators. • The anaerobic sludge granular process was accelerated under FeS NPs stimulation. • The ability to resist environmental stress was enhanced in the coupled system. • Species related to reduction, Fe and S metabolism were enriched in coupled system. [ABSTRACT FROM AUTHOR]

[Display omitted] • A modified graphite felt was prepared by CB/PTFE as a cost-efficient cathode material. • H 2 O 2 could be produced efficiently using MGF without O 2. • The constructed flow-through electro-Fenton reactor was verified effective in degrading mixed chlorinated hydrocarbons. • Testing MGF H 2 O 2 production in a real contaminated groundwater field. A modified graphite felt (MGF) was prepared with carbon black (CB) and polytetrafluoron (PTFE) for cathodic electrochemical H 2 O 2 production, which was used in a flow-through cathodic electro-Fenton reactor to degrade chlorinated hydrocarbons. Cathode electrode was floating on aqueous surface and 369.1 mg/L H 2 O 2 could be produced after 1 h 150 mA power applied without O 2 aeration. The main O 2 source for H 2 O 2 production was confirmed from air with this floating position. In a 2.0 L flow-through cathodic electro-Fenton system, 95.97 % degradation efficiency for 5.0 mg/L trichloroethylene (TCE) was achieved in 90 min with 13.4 mL/min influent rate. Reducing the reactor volume to 0.14 L, 5.0 mg/L TCE could be degraded completely in 10 min with continuous 4 L influent. The mixed chlorinated hydrocarbons (TCE, cis -1,1-dichloroethylene, 1,2-dichloroethane, and dichloromethane) were also rapidly degraded in 20 min. The flow-through cathodic electro-Fenton reactor presented excellent degradation ability for chlorinated hydrocarbons with a smaller volume. In the simulated sand tank system, after continuously operated 27 days, H 2 O 2 concentration in electrode well was still remained at 80 mg/L. In the contaminated field in Tianjin, China, H 2 O 2 yield of MGF in groundwater could keep at about 60 mg/L after 220 min operating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microemulsion preferentially solubilized more polar CHs in mixture. • The selective solubilization was strengthened with increasing temperature. • Increasing flow rate, media size, saturation inhibited priority solubilization. • Lower injection velocity and tinier size media improved removal efficiency. The chlorinated hydrocarbons (CHs) are typically released to the aquifer as complex mixture, and the contaminant type takes the critical action on the in-situ microemulsion formation and solubilization behaviors. However, few interst has been paid to the solubilization behaviors of microemulsion for multiply CHs and the factors affecting selective solubilization. The current work investigated the effect of hydrogeochemical conditions on microemulsion competitive solubilization, and focused on the selective desorption and removal performance of in-situ microemulsion drenching under the various drenching situations. The results elucidated that the apparent solubility of CH was enhanced with adding inorganic salts and the decreasing temperature. In-situ microemulsion showed a preference for dissolving the more polar CHs (CF) in chlorinated hydrocarbon mixture. The selective solubilization was strengthened with increasing temperature, independent of alcohols and salts. The removal efficiency of microemulsion drenching for multiply CHs could achieve 96.0 %, improving with the tinier particle media and lower flow rates. Compared to other CHs, CF was more likely to be desorbed from aquifer medium in multicomponent systems. Furthermore, the selective desorption for multiply CHs was associated with flow rates, media size and residual saturation of contaminants. The inhibition for preferential desorption was more intense to the increase of injection velocity, media size and residual saturation. This insight of selective solubilization behavior can be used to advances the application of in-situ microemulsion drenching for site remediation of multiply CHs. [ABSTRACT FROM AUTHOR]

• The broad-spectrum reactivity of sulfidated ZVI toward chlorinated compounds was evaluated. • Sulfidation favors direct electron transfer and thus the reduction of high chlorinated compounds. • Sulfidation hinders H* mediated reaction and thus the reduction of low chlorinated compounds. • Sulfidation can alter the products distribution during the dechlorination process by ZVI. Contrasting effects of sulfidation on contaminants reduction by zero-valent iron (ZVI) has been reported in literature but the underlying mechanisms remain unclear. Here, under well-controlled conditions, we compared the performance of ZVI and sulfidated ZVI (S-ZVI) toward a series of chlorinated compounds. Results revealed that, although S-ZVI was more reactive than ZVI toward hexachloroethane, pentachloroethane, tetrachloroethylene, and trichloroethene, sulfidation hindered the dechlorination of the other ten tested chlorinated aliphatics by a factor of 1.5–125. Moreover, S-ZVI may lead to an accumulation of toxic partially-dechlorinated products. Analogous to its effects on ZVI reactivity, sulfidation also exerted positive, negligible, or negative effects on the electron efficiency of ZVI. Solvent kinetic isotope effect analysis suggested that direct electron transfer rather than reaction with atomic hydrogen was the dominant reduction mechanism in S-ZVI system. Hence, the sulfidation enhancing effects could be expected only when direct electron transfer is the preferred reduction route for target contaminants. Furthermore, linear free energy relationships analysis indicated one-electron reduction potential could be used to predict the transformation of chlorinated ethanes by S-ZVI, whereas for chlorinated ethenes, their adsorption properties on S-ZVI determined the dechlorination process. All these findings may offer guidance for the decision-making regarding the application of S-ZVI. [Display omitted] [ABSTRACT FROM AUTHOR]

Surfactant-enhanced in-situ chemical oxidation (S-ISCO) is widely applied in soil and groundwater remediation. However, the role of surfactants in the reactive species (RSs) transformation remains inadequately explored. This work introduced nonionic surfactant Tween-80 (TW-80) into a nano zero-valent iron (nZVI) activated persulfate (PS) system. The findings indicate that PS/nZVI/TW-80 system can realize the concurrent removal of trichloroethylene (TCE), tetrachloroethene (PCE), and carbon tetrachloride (CT), whereas CT cannot be eliminated without TW-80 presence. Further analysis unveiled that hydroxyl (HO•) and sulfate radicals (SO 4 －•) were the primary species for TCE and PCE degradation, while CT was reductively eliminated by surfactant radicals generated from TW-80. Moreover, the surfactant radicals were found to accelerate Fe(III)/Fe(II) cycle, reduce the production of iron sludge, and increase PS decomposition. The possible degradation routes of mixed chlorinated hydrocarbons (CHCs) and the decomposition pathways of TW-80 were proposed through the density function theory (DFT) calculation and intermediates analysis. Additionally, the effects of other nonionic surfactants on the simultaneous removal of TCE, PCE, and CT, and the practical applications using the actual contaminated groundwater were also evaluated. This study provides theoretical support for the simultaneous removal of CHCs, particularly those containing perchlorinated contaminants, using the S-ISCO techniques. [Display omitted] • Simultaneous removal of CHCs (TCE, PCE, and CT) was achieved with TW-80 presence. • TCE and PCE were degraded by HO• and SO 4 －•, while CT was reductively eliminated by surfactant radicals. • The accelerated Fe(III)/Fe(II) cycle by the surfactant radicals was confirmed. • Possible degradation pathways of CHCs and TW-80 decomposition routes were proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biodegradation of biochar-adsorbed trichloroethylene (TCE) by Dhc 195 was studied. • 87.5 % of biochar-adsorbed TCE was biodegraded to ethene within 63 days. • Adsorption capacity of biochar remained 80.4% after 5-time bioregeneration cycles. • Electron transfer from Dhc 195 to TCE was mediated by biochar for biodegradation. • Biodegradation of adsorbed TCE required more VB 12 but had a wider pH tolerance. Biochars was widely employed to immobilize chlorinated aliphatic hydrocarbons (CAHs) in groundwater. Biodegradation of adsorbed CAHs may be able to regenerate biochars, but was scarcely explored. In this study, therefore, biodegradation of trichloroethylene (TCE) adsorbed on a biochar prepared at 700 °C (WBC700) by Dehalococcoides mccartyi 195 (Dhc 195) was investigated. Aqueous TCE was completely degraded to ethene by Dhc 195 within 28 days, while 87.5 % of WBC700-adsorbed TCE was degraded to ethene within 63 days. The slower biodegradation of WBC700-adsorbed TCE could be attributed to its lower accessibility to Dhc 195 caused by the steric effects of WBC700. The adsorption capacity of WBC700 for TCE remained 80.4 % after five adsorption-bioregeneration cycles, indicating that the microbial degradation could be a highly efficient method to regenerate biochars. The microbial degradation was mainly through the electron transfer from Dhc 195 to TCE mediated by biochars as electron conductor or shuttle, but was not assisted by desorption or extracellular redox active species. Compared with biodegradation of aqueous TCE, the biodegradation of WBC700-adsorbed TCE by Dhc 195 had a wider pH tolerance and required more VB 12 , due to the buffer effect and adsorption of WBC700, respectively. The obtained results could provide a cost-effective method of biochar regeneration for CAHs removal in groundwater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient dechlorination in nitrate-containing groundwater was explored. • mZVI was modified with three methods and combined with anaerobic bacteria (AB). • S-mZVIbm/AB significantly improved TCE removal efficiency and rate. • S-mZVIbm/AB achieved satisfactory dechlorination ratio and improved N 2 selectivity. • S-mZVIbm/AB was the best sustainable alternative when comprehensively evaluated. Coupling microscale zero-valent iron (mZVI) and anaerobic bacteria (AB) for removal of chlorinated aliphatic hydrocarbon (CAHs) in groundwater is challenging due to decreased efficiency and undesirable products caused by the coexisting nitrate (NO 3 –). Therefore, in this study, mZVI is modified using three methods (sulfidation, carbon modification, and Fe2+ dosing) and combined with AB to construct coupled systems to investigate the removal performance of trichloroethylene (TCE) in the presence of NO 3 –. Among all the treatments, sulfidated mZVI coupled with AB (S-mZVIbm/AB) yields the highest TCE removal efficiency, removal rate, electron efficiency, and complete dechlorination ratio, as well as improved N 2 selectivity. Sustainability evaluation, which considers both technical and environmental indicators, show that S-mZVIbm/AB is the best remediation strategy with the lowest combined utility function value. The reaction kinetics, material characterization as well as bacterial community analysis in S-mZVIbm/AB prove that the sulfidation of mZVI enhances chemical dechlorination, which consequently weakens the chemical reduction of NO 3 – by mZVI and facilitates biodenitrification. These findings highlight the potential of S-mZVIbm/AB as a sustainable solution for groundwater remediation at CAHs-contaminated sites where NO 3 – coexists and provide some suggestions for its practical application. [ABSTRACT FROM AUTHOR]

While anaerobic digestion (AD) has been employed for the degradation of chlorinated aliphatic hydrocarbons, the associated digester performance might suffer from volatile fatty acids accumulation, insufficient substrate-microbes interaction, and lower biogas yields. To overcome these limitations, this study is the first to augment the hydrocarbon-degrading microbial capacities by adding agricultural waste-based biochar to the digestion medium. 1,2-dichloroethane (1,2-DCA) was selected as the target pollutant because it is discharged in large quantities from oil refining, petrochemical, and chemical industries, causing serious environmental and human health concerns. A multi-chamber anaerobic reactor (MAR) was operated at a 1,2-DCA loading rate of 1.13 g/L/d, glucose dosage (as an electron donor) range of 200–700 mg/L, and hydraulic retention time of 11.2 h, giving dechlorination = 32.2 ± 6.9% and biogas yield = 210 ± 30 mL/g COD removed. These values increased after biochar supplementation (100 mg/g volatile solids, VS, as an inoculum carrier) up to 60.2 ± 11.5% and 290 ± 40 mL/g COD removed , respectively, owing to the enhancement of dehydrogenase enzyme activities. Burkholderiales (15.3%), Clostridiales (2.3%), Bacteroidales (3.5%), Xanthomonadales (3.3%), and Rhodobacterales (6.1%) involved in 1,2-DCA degradation were dominant in the reactor supplemented with biochar. It's suggested that biochar played a major role in facilitating the direct interspecies electron transfer (DIET) between syntrophic bacteria and methanogens, where chloride, ethylene glycol, and acetate derived from 1,2-DCA dechlorination could be further used to promote methanogenesis and methane production. The synergetic effect of adsorption and dechlorination towards 1,2-DCA removal was validated at various biochar dosages (50–120 mg/g) and 1,2-DCA concentrations (50–1000 mg/L). The techno-economic results showed that the cost of treating 1,2-DCA-laden discharge (100 m3/d) by the MAR module could be 0.83 USD/m3 with a payback period of 6.24 years (NPV = 2840 USD and IRR = 10%), retrieving profits from pollution reduction (9542 USD/yr), biogas selling (10418 USD/yr), and carbon credit (10294 USD/yr). [Display omitted] • 1,2-dichloroethane was removed by biochar assisted multi-chamber anaerobic reactor. • The enzymes and metabolic activity of methanogens was improved by biochar addition. • The biochar addition increased the abundance of Bacteroidales and Xanthomonadales. • Chloride, ethylene glycol and acetate were the main metabolites of 1,2-DCA degradation. • 1,2-DCA-laden discharge treatment cost was 0.83 $/m3 with payback period of 6.24 yr. [ABSTRACT FROM AUTHOR]

We present a solution for long-term direct current resistivity and time-domain induced polarization (DCIP) monitoring, which consists of a monitoring system and the associated software that automates the data collection and processing. This paper describes the acquisition system that is used for remote data collection and then introduces the routines that have been developed for pre-processing of the monitoring data set. The collected data set is pre-processed using digital signal processing algorithms for outlier detection and removal; the resulting data set is then used for the inversion procedure. The suggested processing workflow is tested against a simulated time-lapse experiment and then applied to field data. The results from the simulation show that the suggested approach is very efficient for detecting changes in the subsurface; however, there are some limitations when no a priori information is used. Furthermore, the mean weekly data sets that are generated from the daily collected data can resolve low-frequency changes, making the approach a good option for monitoring experiments where slow changes occur (i.e. leachates in landfills, internal erosion in dams, bioremediation). The workflow is then used to process a large data set containing 20 months of daily monitoring data from a field site where a pilot test of in situ bioremediation is taking place. Based on the time-series analysis of the inverted data sets, we can detect two portions of the ground that show different geophysical properties and that coincide with the locations where the different fluids were injected. The approach that we used in this paper provides consistency in the data processing and has the possibility to be applied to further real-time geophysical monitoring in the future. [ABSTRACT FROM AUTHOR]

Stir-bar sorptive extraction followed by liquid desorption with gas chromatography using electron capture detection had been applied for the determination of eleven chlorinated hydrocarbons (mainly chlorobenzenes) in water matrix. The optimisation of parameters that could influence SBSE-LD efficiency on both extraction and desorption steps was carried out. Parameters such as time and temperature of extraction, salt and stirring rate, type of back desorption solvent, desorption time and temperature, ultrasonic effect were studied and optimised. The highest extraction efficiency was obtained using 60 min extraction time (1000 rpm; 35°C), a solution containing 10% (w/v) sodium chloride and 30 min for the desorption period with ethyl acetate as back-extraction solvent. Under these conditions, the method gives limits of detection in the range from 0.3 to 4.0 ng L−1, a linear dynamic range of 50–1000 ng L−1 and the relative standard deviations are ≤11.1%. The obtained high relative recoveries for the determination of chlorinated hydrocarbons in various water environmental samples testify to the possibility of practical application of the developed method. The results demonstrate that the technique is simple and sensitive, and thus represents an attractive alternative for ultra-trace analysis of chlorinated hydrocarbons in water samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Operando DRIFT investigates TCE adsorption and transition on CeO 2 nanorods. • Transition metals on CeO 2 enhance oxygen vacancies and medium-strong acidic sites. • Cr-CeO 2 activates TCE on acidic sites via C-Cl cleavage at low temperatures. • Cu-CeO 2 and V-CeO 2 generate polychlorinated intermediates and therefore C 2 Cl 4. • High oxygen storage capacity and acidity of Cr-CeO 2 lead to its superb reactivity. The remediation of chlorinated volatile organic compounds is an intractable issue for it typically requires high temperatures and generates undesirable byproducts. This work utilized a series of representative transition metals (i.e., Cr, Cu, V) to modify the morphology, surface oxygen, and acidity of the CeO 2 nanorods for trichloroethylene (TCE) treatment. A spectroscopic operando DRIFT − online GCMS reactor was introduced to examine the catalytic performance and elucidate the reaction pathway. Among them, Cr-CeO 2 exhibited 50 % (T 50) and 90 % (T 90) TCE conversions with no byproduct at 171 °C and 241 °C, respectively. The performances of Cu-CeO 2 (T 90 = 391 °C), V-CeO 2 (T 90 = 423 °C) and CeO 2 (T 90 = 494 °C) were inferior to Cr-CeO 2 (T 90 = 241 °C), with obvious C 2 Cl 4 generated in the TCE oxidation. It reveals that TCE adsorbed on Cr-CeO 2 is dechlorinated on acidic sites and oxidized to carbonate/formate intermediates by the surface oxygen then facilely to generate carbon oxides, while TCE is adsorbed as chlorinated species (CH 2 ClCH 2 O−) on the other three catalysts which occupy the surface and require higher temperature to be oxidized. The abundant medium-strong acidic sites and surface oxygen species of Cr-CeO 2 nanorods are responsible for the low-temperature activation via C-Cl cleavage on acidic sites and fast oxidation of hydrocarbon intermediates in the TCE oxidation, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dodecylamine induced active Co3+ on Co 3 O 4. • PS prevented the elimination of active Co3+ during calcination by forming C Co O. • O 3 pre-treatment removed deposited carbon to expose active Co3+. • Chemosorbed oxygen facilitated the conversion of O 3 into O. • Photogenerated holes oxidized the intermediates formed after DCM dechlorination. The activation of C Cl bonds and the conversion of O 3 are crucial for the degradation of chlorinated hydrocarbons through catalytic ozonation. This work constructed the surface active sites of Co 3 O 4 with polystyrene (PS) and dodecylamine to enhance dichloromethane (DCM) removal and O 3 conversion in photo-ozone catalysis simultaneously. The dodecylamine created active Co3+ on the catalyst surface, and the PS prevented the elimination of active Co3+ during calcination by forming C Co O. The O 3 pre-treatment removed the deposited carbon to expose the active Co3+ and the chemisorbed oxygen. The surface Co3+ played a crucial role in cleaving the C Cl bonds of DCM, and the chemosorbed oxygen facilitated the conversion of O 3 into O. Moreover, the photogenerated holes oxidized the intermediates formed after the DCM dechlorination. The removal rate of DCM for the sample co-modified by PS and dodecylamine was 80.8 mg/(g‧h) under one sun irradiation, which was 2.2 times higher than that by Co 3 O 4. [ABSTRACT FROM AUTHOR]

• Sulfidation/nitridation significantly enhanced the hydrophobicity of nZVI. • Reactivity towards florfenicol (FF) correlated well with hydrophobicity of nZVI. • Sulfidation/nitridation did not enhance nZVI reactivity for chloramphenicol (CAP). • Sulfidation/nitridation improved dechlorination activity of nZVI for FF and CAP. • Sucralose may serve as a recalcitrant compound to examine nZVI reactivity. Sulfidation and nitridation have been reported as promising methods to modify nanoscale zero-valent iron (nZVI) for water decontamination from chlorinated organic compounds (COCs). However, the effects of sulfidation/nitridation on the reactivity of nZVI towards COCs of different polarities were poorly understood. To explore such effects, nZVI, one-step sulfided nZVI (S 1 -nZVI), two-step sulfided nZVI (S 2 -nZVI), and nitrided nZVI (N-nZVI) were prepared in this study, and chloramphenicol (CAP), florfenicol (FF), and sucralose (SUC) were employed as typical COCs with sequentially increasing polarities. Sulfidation and nitridation significantly enhanced the hydrophobicity of nZVI as observed from water contact angle. Anaerobic condition favored FF degradation by all the four nZVI-based materials, while sulfidation and nitridation could inhibit the competition effect of coexisting nitrate on FF removal by nZVI. The reactivity of the nZVI-based materials towards FF followed the same order of water contact angle, while sulfidation/nitridation did not enhance the reactivity of nZVI towards CAP. Intriguingly, sulfidation/nitridation was found to improve the activity of nZVI for dechlorination reactions during FF and CAP degradation, and N-nZVI exhibited particularly high dechlorination capability (∼90 % for FF and ∼100 % for CAP). In contrast, all the investigated nZVI-based materials had no activity in SUC degradation, indicating the negligible role of sulfidation/nitridation in promoting the reactivity of nZVI towards COCs of strong polarity. In addition, SUC may serve as a recalcitrant target compound to examine the reactivity of modified nZVI materials. This study sheds light on the development of nZVI modification strategies/methods for more efficient water treatment. [ABSTRACT FROM AUTHOR]

The membrane interface probe (MIP) is an efficient and economical in-situ tool for chlorinated hydrocarbon (CH) contaminated site investigation. Given that the interpretation of MIP test is currently limited to a qualitative level, a theoretical model considering multiphase flow and multifield coupling is firstly proposed to simulate MIP test process. This model can consider phase change, membrane effect, adsorption and dissolution of the CH liquid, gas diffusion, and evaporation. Then, the model is used to study the changes in soil temperature and soil CH concentration during MIP test, as well as the influences of soil CH concentration and soil properties (initial water saturation, soil intrinsic permeability, and thermal properties) on MIP response. Finally, a simplified MIP interpretation model is developed based on parametric analysis results and verified against field and laboratory test data. It is found that the soil CH concentration, rather than soil properties, dominates the MIP response. The simplified interpretation model can deliver practical prediction of the CH concentration through the detected results by MIP, which may improve the applicability of MIP. [Display omitted] • A theoretical model is developed to reveal the MIP test mechanism. • MIP test process can be effectively divided into three stages. • Soil CH concentration, rather than soil properties, dominates the MIP response. • A simplified model is proposed to predict CH concentration directly by MIP. • The simplified model may improve the applicability of MIP. [ABSTRACT FROM AUTHOR]

[Display omitted] • The dechlorination of TCE by MoS-mZVI was 26.17-fold faster than that of mZVI. • MoS-mZVI exhibited high electron utilization efficiency of 65.6%. • MoS 2 ′s selective OH adsorption contributes to pH reduction, effectively mitigating. • mZVI passivation and optimizing its reactivity. The potential of microscale zero-valent iron (ZVI) for dechlorinating chlorinated hydrocarbons holds promise in pollution remediation. However, Fe0 passivation presents a challenge, leading to slow dechlorination and the buildup of hazardous incomplete dechlorinated intermediates. To address these concerns, we introduce molybdenum disulfide (MoS 2)-modified microscale ZVI (MoS-mZVI). Our study demonstrates the significant enhancement of trichloroethylene (TCE) dechlorination by MoS-mZVI compared to standard mZVI. Remarkably, the optimal Fe/MoS 2 molar ratio of 20 in MoS-mZVI achieves a remarkable 26.8-fold acceleration in TCE removal compared to mZVI. Acetylene emerges as the primary intermediate in TCE dechlorination by MoS-mZVI, peaking at 38%, accompanied by major end products including ethene (45%) and ethane (31%). Importantly, the MoS-mZVI-20 system avoids toxic byproducts, diverging from the dichloroethylene accumulation observed in the mZVI system. Notably, electron utilization efficiency shows significant improvement, with MoS-mZVI reaching 65.6% compared to mZVI's 7.2%. Furthermore, MoS 2 ′s selective OH- adsorption triggers pH reduction, mitigating mZVI passivation and optimizing its reactivity. This innovative approach highlights the effectiveness of MoS 2 -modified microscale ZVI as an environmentally friendly solution for enhancing TCE dechlorination processes. [ABSTRACT FROM AUTHOR]

Resource recovery from solid organic wastes, such as degradable plastics, and upgrading raw bio-oil are important ways for reducing carbon and pollution emissions. Hydrodeoxygenation (HDO) is a common thermochemical treatment to upgrade crude bio-oil. In this study, in order to realize in situ HDO during the hydropyrolysis of heavy bio-oil and degradable plastics, a reduced Fe/Ce oxygen carrier (OC) was used to catalytically remove oxygen from organics under the methanol-zero valent aluminum (ZV Al) media, where the hydrogen was produced during pyrolysis instead of a direct hydrogen supply. The results showed that the reduced OC captured the oxygen from the pyrolysis products of heavy bio-oil and degradable plastic, representing the multi-selectivity of reduced OC to phenols, ketones, etc. The ZV Al system promoted the production and utilization of hydrogen, as evidenced by the increased hydrogen content in gas phase and hydrocarbon content in liquid phase. The hydrocarbon component distribution in the liquid phase increased clearly when hydropyrolysis with degradable plastics addtion, but the excess degradable plastics addition caused increasing of the liquid product viscosity, and decreasing of the liquid products yield for the higher ash content in degradable plastic, and a higher ZV Al amount was required to maintain the hydropyrolysis. Molecular dynamics simulations verified the synergistic effect of degradable plastics and bio-oil by the pyrolysis behavior in different systems and temperatures, and the pyrolysis pathways were proposed. This non-autocatalytic system realized the resource recovery and heavy bio-oil upgrading using an Fe/Ce OC. [Display omitted] • A methanol-zero valent aluminum media is used to provide reactive hydrogen. • Reduced iron oxide plays a dual function of oxygen carrier and catalyst for HDO. • Degradable plastics are used in co-pyrolysis with heavy bio-oil for resource utilization. • The upgrading mechanism is understood by a combination of experimental and molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

The efficient biodegradation of volatile chlorinated hydrocarbons using microbial fuel cells (MFCs) offers a feasible approach for purifying waste gas and alleviating energy crises. However, power generation is limited by poor pollutant biodegradation and slow electron transfer. The bifunctional bacterium Acinetobacter sp. HY-99C was screened and used to improve the performance of a conventional MFC. The inoculation of strain HY-99C into the conventional MFC promoted the formation of a compact biofilm with high metabolic activity and an enriched bifunctional genus (Acinetobacter), which resulted in the accelerated decomposition of chlorinated aromatic compounds into biodegradable organic acids. This led to efficient chlorobenzene removal and power generation from the MFC, with a chlorobenzene elimination capacity of 70.8 g m−3 h−1 and power density of 89.6 mW m−2, which are improved over those of previously reported MFCs. This study provides novel insights into enhancing pollutant removal and power generation in MFCs. The inoculation of bifunctional Acinetobacter sp. HY-99C will promote the application of microbial fuel cell to simultaneously remove volatile chlorinated hydrocarbons and alleviate the energy crisis. [Display omitted] • Strain HY-99C achieved outstanding chlorobenzene removal and power generation. • Biofilm formation was accelerated in the microbial fuel cell with strain HY-99C. • Strain HY-99C inoculation chanced the metabolic activity and electron transfer. • Bifunctional (degrader & exoelectrogen) Acinetobacter was directionally enriched. • Niche competition between degrader & exoelectrogen was weakened by Acinetobacter. [ABSTRACT FROM AUTHOR]

Stable and selective gas sensing is essential to detect toxic gases and avoid gas leak accidents. Two-dimensional (2D) materials are potential sensing materials for making gas sensors because of their high surface-to-volume ratios, broad surface activity, and defect sites. In this work, a recent 2D material, borophene, is used as the NO 2 gas-sensing material. Polyetherimide (PEI) incorporated with the Zeolitic imidazole framework (ZIF-8) with different loading (mixed matrix membrane, MMM) is used as a selective gas separation membrane for its solubility (imide, isopropylidene and ether groups on PEI) and diffusion (porosity) properties. The MMM was selective to NO 2 gas as ZIF-8 is selective towards NO 2 gas, and PEI is resistant to substances like hydrocarbons, alcohols, and halogenated solvents. A slight variation in borophene's gas sensing response (0.6%) was observed for 25 ppm NO 2 at 25 °C and 35% relative humidity (RH) with and without the PEI-ZIF-8 filter, showing the MMM filter is not affecting the sensing response highly. As ZIF-8 is hydrophobic, the borophene sensor showed higher stability at higher RH conditions. These findings suggest that fabricated sensors can detect NO 2 gas at varying concentrations for environmental and human safety. [Display omitted] • Mixed matrix membrane (MMM) for superior selectivity and stability in gas sensing. • Development of borophene-based chemiresistive NO 2 gas sensor. • Optimized ZIF-8 loading in Polyetherimide (PEI) to enhance NO 2 sensing capacity. • PEI-ZIF-8 (1:4) MMM filter demonstrated enhanced stability and selectivity for NO 2 gas. [ABSTRACT FROM AUTHOR]

[Display omitted] • GEO n S-m aggregate was vesicle, rodlike and spherical micelle as the EO increases. • PCE/CT and TCE/MCB each mainly solubilized in micelle's interior and palisade layer. • Decrease of EO number and hydrophobic chain would increase the solubilization rate. • Micelles expanded and rod micelle split as chlorinated hydrocarbons solubilized. • Solubilization of GEO n S-m conformed to oil diffusion & micelle reformation model. Accurate prediction and modeling of the quantitative recovery of chlorinated hydrocarbons in an aquifer by anionic-nonionic gemini surfactants requires estimates of their mass-transfer models and capture mechanisms. In this work, a series of synthesized anionic-nonionic gemini surfactants (GEO n S-m) with different molecular structures were used to solubilize different chlorinated hydrocarbons that contaminate the aquifer. GEO n S-m aggregate showed vesicle, rodlike micelle, and spherical micelle as the ethylene oxide content (EO) number increases. Non-polar chlorinated hydrocarbons (PCE, CT) mainly solubilized in the hydrophobic interior of micelles, and polar chlorinated hydrocarbons (TCE, MCB) mainly solubilized in the "palisade layer" of micelles. Solubilization processes were followed employing first-order and second-order kinetics. The solubilization rate increases with the decrease of EO number of GEO n S-m molecules. In essence, lower interfacial tension reduces the mass-transfer resistance of chlorinated hydrocarbons at the two-phase interface. The diameter of vesicles and spherical micelles increases, and rodlike micelles evenly changed to vesicles as chlorinated hydrocarbons transfer into micelles. The solubilization process of GEO n S-m for chlorinated hydrocarbons conforms to a novel "oil diffusion & micelle reformation model" that represents the coupling to two pre-existing models. And the solubilization mass-transfer mathematical model demonstrated the solubilization mass-transfer coefficient is affected by the combination of surfactant and solubilized organic properties. This study advances the application of solubilization for chlorinated hydrocarbons using anionic-nonionic gemini surfactants in surfactant-enhanced aquifer remediation (SEAR) design. [ABSTRACT FROM AUTHOR]

• First report on the remediation of PFASs–CAHs co-contamination using in situ TAP. • Effective distribution of persulfate and achieving target temperature are necessary. • Conversion of PFAAs precursors increased PFAAs concentrations in groundwater. • No inhibitory effects of Cl− on PFASs degradation observed due to sufficient persulfate. The co-occurrence of per- and polyfluoroalkyl substances (PFASs) and chlorinated aliphatic hydrocarbons (CAHs) in groundwater has drawn increased attention in recent years. No studies have been conducted concerning the oxidative degradation of PFASs and/or CAHs by in situ thermally activated persulfate (TAP) in groundwater, primarily due to the difficulty in cost-effectively achieving the desired temperature in the field. In this study, the effects and mechanisms of PFASs degradation by in situ TAP at a site with PFASs and CAHs co-contaminants were investigated. The target temperature of 40.0–70.0 °C was achieved in groundwater, and persulfate was effectively distributed in the demonstration area – the combination of which ensured the degradation of PFASs and CAHs co-contaminants by in situ TAP. It was demonstrated that the reductions of perfluoroalkyl carboxylic acids (PFCAs) concentration in all monitoring wells were in the range of 43.7 %–66.0 % by in situ TAP compared to those maximum rebound values in groundwater, whereas no effective perfluoroalkane sulfonic acids (PFSAs) degradation was observed. The conversion of perfluoroalkyl acids (PFAAs) precursors was one of the main factors leading to the increase in PFCAs concentrations in groundwater during in situ TAP. CAHs were effectively degraded in most monitoring wells, and furthermore, no inhibitory effects of CAHs and Cl− on the degradation of PFASs were observed due to the presence of sufficient persulfate. Additionally, there were significant increases in SO 4 2− concentrations and reductions of pH values in groundwater due to in situ TAP, warranting their long-term monitoring in groundwater. The integrated field and laboratory investigations demonstrated that the reductions in PFCAs and CAHs concentrations can be achieved by the oxidative degradation of in situ TAP. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The removal performance of various types of CHCs was systematically examined. • The predominant reactive species were identified in different enhanced systems. • The removal efficiencies, costs, and toxicity of the enhancers were evaluated. • The most applicable techniques for the single CHC were elucidated. • A complete set of remediation strategies for multiple mixed CHCs were formed. Conventional Fe(II)-based advanced oxidation processes required enhancement to achieve desired contaminant removal. In this study, the introduced enhancers were divided into four categories: organic acids-based enhancers, inorganic reductants, slow-release iron substances, and short-chain alcohols or acids. Chlorinated hydrocarbons (CHCs) were chosen as the targets and classified into three groups: chlorinated olefins, non-perchlorinated alkanes, and perchlorinated alkanes. The remediation effects of different enhanced systems (oxidant/Fe(II)/enhancer) on different types of CHCs were systematically examined. The predominant reactive species were identified and elucidated to provide the most applicable technique for the remediation of each type of chlorinated hydrocarbon. Their dechlorination and mineralization degree were investigated as well. Meanwhile, a complete set of remediation strategies for multiple mixed CHCs in contaminated groundwater were formed by combining the remediation efficiencies, costs, and toxicity of the enhancers, which could provide far-reaching implications for the systemic governance of CHCs in practical applications. [ABSTRACT FROM AUTHOR]

The remediation of sites contaminated with chlorinated hydrocarbons (CHCs) poses a challenge, especially in built up areas. Nanoscale zero-valent iron (nZVI) can reduce CHCs to nontoxic compounds. Jet grouting and deep soil mixing is used to overcome the difficulty of homogeneous distribution of nZVI in heterogeneous soils. Because these techniques facilitate a synergistic contaminant treatment and installation of construction elements, it is important to know the reactive interactions among involved compounds. In this study six binder materials [bentonite and ordinary portland cement (OPC), among others] have been investigated for interactions with the reductive dechlorination of trichloroethylene (TCE) by nZVI. The installation process was simulated in batch experiments, and the reaction products (CHC, intermediate products, and hydrogen) were observed using headspace gas chromatography. None of the binders inhibited dechlorination of TCE compared to a control experiment, and the two clay materials even catalyzed the reaction by a factor of up to 12.9. Hydrogen evolution was determined as a sensible indicator for the suitability of a particular binder, ranging from 12.8 to 4,400 mmol. [ABSTRACT FROM AUTHOR]

Groundwater remediation is one of the main objectives to minimize environmental impacts and health risks. Chlorinated aliphatic hydrocarbons contamination is prevalent and presents particularly challenging scenarios to manage with a single strategy. Different technologies can manage contamination sources and plumes, although they are usually energy-intensive processes. Interesting alternatives involve in-situ bioremediation strategies, which allow the chlorinated contaminant to be converted into non-toxic compounds by indigenous microbial activity. Despite several advantages offered by the bioremediation approaches, some limitations, like the relatively low reaction rates and the difficulty in the management and control of the microbial activity, can affect the effectiveness of a bioremediation approach. However, those issues can be addressed through coupling different strategies to increase the efficiency of the bioremediation strategy. This mini review describes different strategies to induce the reduction dechlorination reaction by the utilization of innovative strategies, which include the increase or the reduction of contaminant mobility as well as the use of innovative strategies of the reductive power supply. Subsequently, three future approaches for a greener and more sustainable intervention are proposed. In particular, two bio-based materials from renewable resources are intended as alternative, long-lasting electron-donor sources (e.g., polyhydroxyalkanoates from mixed microbial cultures) and a low-cost adsorbent (e.g., biochar from bio-waste). Finally, attention is drawn to novel bio-electrochemical systems that use electric current to stimulate biological reactions. [ABSTRACT FROM AUTHOR]

Chlorinated hydrocarbon compounds are of environmental concerns, since they are toxic to humans and other mammals, and are widespread, and exposure is hard to avoid. Understanding and improving methods to reduce the amount of the substances are important. We present an atomic-scale calculational study of the adsorption of chlorine-based substance chloroform (CHCl3) on graphene oxide, as a step in estimating the capacity of graphene oxide for filtering out such substances, e.g., from drinking water. The calculations are based on density functional theory, and the recently developed consistent-exchange functional for the van der Waals density-functional method is employed. We obtain values of the chloroform adsorption energy varying from roughly 0.2 to 0.4 eV per molecule. This is comparable to previously found results for chloroform adsorbed directly on clean graphene, using similar calculations. In a wet environment, like filters for drinking water, the graphene will not stay clean and will likely oxidize, and thus adsorption onto graphene oxide, rather than clean graphene, is a more relevant process to study. [ABSTRACT FROM AUTHOR]

We present a theoretical and experimental study of resonant inelastic x-ray scattering on a large group of chlorinated hydrocarbons: CH3Cl, CH2Cl2, CHCl3, CCl4, CH3CH2Cl, ClCH2CH2Cl, CH3CHCl2, CH3CCl3, C2H2Cl2-iso, C2H2Cl2-cis, C2H2Cl2-trans, and C6H5Cl. Differences in structural and dynamical properties of the molecules generated by diverse chemical environments are observed in the measured Cl(Kα) spectral maps as well as in the Cl(K) total fluorescence yield spectra. The energy position, relative intensity, and the width of the Franck-Condon distribution of low-lying `*and π* resonances are extracted by a fitting procedure taking into account the experimental broadening. The theoretical values obtained with the transition potential and Δ Kohn-Sham methods are in good agreement with the experimental parameters indicating subtle differences due to variations in the molecular structure. [ABSTRACT FROM AUTHOR]

Petroleum hydrocarbon contaminants in groundwater are among the most impactful environmental problems in oil production in southern Iraq, especially Basra city. Petroleum hydrocarbon contaminants affect related projects surrounding the primary pollution site. Benzene, toluene, and dimethylbenzene are the most toxic pollutants affecting the removal of perchloroethene (Cl2C=CCl2) and trichloroethene (C2HCl3) in groundwater. These pollutants have high solubility in water, leading to their transport over long distances in groundwater and difficult removal. The influence of petroleum hydrocarbons on the chlorine removal of perchloroethene and trichloroethene was studied using a polytetrafluorethylene column packed with zero-valent iron (ZVI). Batch experiments were implemented to investigate the equilibrium supply of mixtures between the aqueous and solid stages in packed column systems. It was designated using the Freundlich isotherm expression, and the result showed that R2 was greater than 0.97 for benzene, toluene, and xylene. The column study noted that the reaction constant was decreased in all columns by approximately 48 % when the pore volume was between 50 and 205, which reflects the dechlorination priority of P-CE over T-CE. These findings indicate that benzene and toluene are more effective for adsorption on the ZVI particle surfaces owing to disparate influences. [ABSTRACT FROM AUTHOR]

An approach for quantitative detection of organic vapors is demonstrated. Herein, an interdigited electrode was fabricated by drop casting of graphite loaded poly(phenyl sulfone) (PPSU/Gr) film on a conductive substrate. The sensor is experimentally tested on several organic solvents including alkanes, acetates, aromatic hydrocarbons and chloroform via electrical resistance measurements and inverse gas chromatography (IGC) method. Relationships between the sensor response (as obtained by electrical resistance) and solvent properties such as polarity, acidity and partition coefficient (as obtained from IGC) are established. Moreover, the surface dispersive free energy of PPSU and PPSU/Gr were calculated according to both Dorris-Gray and Schultz equations, it is found that with the addition of graphite to PPSU the surface dispersive free energy of PPSU at 25 °C decreased from 28 to 10 mJ m−2 (from Dorris Gray approach) and from 25 to 17 mJ m−2 (from Schultz approach), suggesting higher interfacial area for exposed gases at PPSU/Gr sensor. Furthermore, the PPSU/Gr modified electrode exhibited high sensitivity towards chlorinated hydrocarbons. Importantly, the PPSU/Gr electrode showed good mechanical stability, low response time, and is costly-effective and disposable, rendering it a promising sensor for gases detection. [ABSTRACT FROM AUTHOR]

Reactions of the [Os3H2(CO)10] cluster complex (1) with six‐membered heterocyclic amines (morpholine, thiomorpholine, piperidine) and halohydrocarbons (CH2Cl2, ClHC=CHCl, CH2=CCl2) at ∼25 °C have been studied. Two main types of products are formed in all studied reactions. One product is carbene cluster [Os3(μ−H)(μ−Cl){η1−C(CH3)N(CH2CH2)2X}(CO)9] (X=O, S, CH2) (3, 3 a and 3 b). Second product is cluster containing enamine ligand [Os3(μ−H){μ‐CH=CHN(C2CH2)2Х)}2(CO)10] (X=O, S, CH2) (2, 2 a and 2 b). The carbene ligand is assembled on a cluster, from three organic molecules, thus representing the first example of carbene ligands formed in this way. Clusters with carbene ligand exist as two stable isomers (rotamers hindered towards the Os−C bond), as confirmed by NMR studies and conformational analysis. We have found that in reactions of cluster 1 with acyclic amines containing an oxygen atom in γ‐position (likely morpholine in CH2Cl2), only complexes with bridging enamine ligands are formed. Compounds 2 a, 2 b, 3 and 3 b are characterized by single‐crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]