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Global ecological damage caused by economic development has prompted various regions worldwide to explore sustainable development pathways. This study aims to elucidate the micro-level impacts of macro-development strategies on towns' development to guide future regional management. The spatiotemporal changes in the coupling coordination between gross ecosystem product (GEP) and gross domestic product (GDP) were measured at various scales. The GEP results were adjusted based on harvest pressure, management intensity, and succession stage. Spatial simulations of GDP are conducted at a 30m resolution using VIIRS nighttime light data. The results showed that the GEP-GDP coupling coordination changes among the 14 towns in Dongtai City exhibited significant spatiotemporal variations and distinct gradient characteristics between 2010 and 2020. GEP-GDP coupling coordination of both city and town levels significantly decreased, with noticeable differences between the eastern and western regions. The study reveals an intensification of economic-ecological conflicts at both the overall and local levels. However, the performance of the city scale masked the great differences at the town scale. Therefore, the development balance at the town level needs wider attention in areas such as land use and development planning. • The coupling coordination of 13 towns has undergone significant regional differences. • Performance of the city scale masks the great differences at the town scale. • The imbalance of ecological and economic development in all towns has intensified. • Development optimization and priority partitioning on the town scale are feasible. [ABSTRACT FROM AUTHOR]

The ammonia/chlorine oxidation process can greatly degrade PPCPs in water. However, its effect on molecular transformations of natural organic matter (NOM) and effluent organic matter (EfOM) are still poorly understood. In this study, molecular transformations of NOM and EfOM occurring during ammonia/chlorine were explored and compared with those occurred during chlorination, using spectroscopy and mass spectrometry. Phenolic and highly unsaturated aliphatic compounds together with aliphatic compounds were found to be predominant in both NOM and EfOM samples, all of which were significantly degraded after two processes. The ammonia/chlorine process led to greater decreases in the molecular weights of such components but lower reductions in aromaticity. Compared with chlorination, ammonia/chlorine was found to be more likely to degrade compounds while remaining fluorophores or chromophores. The CH(N)O(S) precursors were found to be similar for both processes but their products were quite different. The CH(N)O(S) precursors that only found in ammonia/chlorine had higher molecular weights and greater degrees of oxidation but lower degrees of saturation. In contrast, the unique CH(N)O(S) products that only found in ammonia/chlorine exhibited lower molecular weights and lower degrees of oxidation degrees together with higher degrees of saturation. Lower total abundance of chlorinated byproducts was found by ammonia/chlorine compared with chlorination, although the former process provided a richer diversity. In all water samples, chlorinated byproducts were mainly generated by substitution reactions during ammonia/chlorine and chlorination. Overall, the findings of this study could provide new insights into the transformations of NOM and EfOM induced by ammonia/chlorine and chlorination. [Display omitted] • Ammonia/chlorine led to greater declines in MW and smaller reductions in AI. • Chlorination and ammonia/chlorine shared most precursors but differed in products. • Substitution was the main pathway to chlorinated byproducts in all samples. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) is widely used in industry but is difficult to degrade. In this study, the synergistic effect of UV irradiation and chlorination on degradation of PVA was investigated. UV irradiation or chlorination alone did not degrade PVA. By contrast, UV/chlorine oxidation showed good efficiency for PVA degradation via generation of active free radicals, such as OH and Cl. The relative importance of these two free radicals in the oxidation process was evaluated, and it was shown that OH contributed more to PVA degradation than Cl did. The degradation of PVA followed pseudo first order kinetics. The rate constant k increased linearly from 0 min −1 to 0.3 min −1 with increasing chlorine dosage in range of 0 mg/L to 20 mg/L. However, when the chlorine dosage was increased above 20 mg/L, scavenging effect of free radicals occurred, and the degradation efficiency of PVA did not increase much more. Acidic media increased the degradation efficiency of PVA by UV/chlorine oxidation more than basic or neutral media because of the higher ratio of [HOCl]/[OCl − ], higher free radical quantum yields, and the lower free radical quenching effect under acidic conditions. Results of Fourier Transform Infrared Spectroscopy showed that carbonyl groups in degradation products were formed during UV/chlorine oxidation, and a possible degradation pathway via alcohol to carbonyl was proposed. [ABSTRACT FROM AUTHOR]

• Ammonia/chlorine markedly enhanced the degradation of structurally diverse PPCPs. • Hydroxyl radicals predominated in all PPCP degradations. • Ammonia/chlorine was feasible to degrade PPCP in reclaimed water. • Fewer volatile halogenated byproducts were formed by ammonia/chlorine. Pharmaceutical and personal care products (PPCPs) are frequently detected in water bodies and have potential risks to human health and the ecosystem. The degradation of eight structurally diverse PPCPs by ammonia/chlorine was systematically investigated in this study. Compared with chlorination, ammonia/chlorine markedly enhanced PPCP degradation, and the degradation efficiencies of most PPCPs were greater than 70%. Tert-butanol strongly suppressed PPCP degradation, while bicarbonate suppressed it moderately, suggesting the importance of ClO⋅and ⋅CO 3 − in PPCP degradation. In neutral conditions, PPCP degradation was mainly attributed to ⋅OH, with its contribution ranging from 74% to 100% at a Cl 2 /N molar ratio of 1.6. Regarding the effect of natural organic matter, atrazine and primidone were inhibited the most, while carbamazepine (CBZ), metoprolol (MTP), and atenolol (ATN) were affected the least. PPCP degradation was suppressed in reclaimed water; the degradation of CBZ, MTP, and ATN was suppressed the least, with degradation efficiencies of 77.1%–85.4%, 75.1%–77.1%, and 64.6%–68.8%, respectively. Furthermore, compared with chlorination, fewer volatile halogenated byproducts were formed in reclaimed water when using the ammonia/chlorine process, and the concentration of each byproduct formed by ammonia/chlorine was less than 10 µg/L. This study suggests the feasibility of using ammonia/chlorine oxidation to degrade PPCPs in reclaimed water. [Display omitted] [ABSTRACT FROM AUTHOR]

With the rural revitalization strategy was proposed in 2017, large-scale land consolidation has been carried out in rural areas of China, which has profoundly impacted rural development and sustainability. To assess the multi-dimensional effects of land consolidation on rural revitalization, an evaluation system was constructed following the proposed "target-indicator-outcome" framework and subsequently applied to 193 cases documented in 92 peer-reviewed articles for a systematic review and meta-analysis. The results indicate that rural land consolidation had played more positive than no/negative roles in facilitating rural revitalization, with cases reporting generally positive outcomes accounting for 74%. Considering four targets of rural revitalization, positive effects were statistically significant in the case of Prosperous Life and Industrial Prosperity, with positive cases accounting for 86% and 79%. However, the positive effects in terms of Ecological Livability and Rural Civilization & Effective Governance is statistically non-significant, with positive cases accounting for 65% and 47%. In terms of 12 indicators, an overview of the positive and no/negative effects brought by land consolidation were summarized. The cases of the indicators related to rural producting and living were largely positive, however, the indicators related to rural ecology, rural civilization and governance reported higher no/negative outcomes. From the perspective of spatial differentiation, the positive effects were significant in eastern, central and western China, and the proportion of positive cases in eastern China (80%) and western China (77%) were higher than those in central China (67%). The opportunities and threats of rural land consolidation in multi-dimension deserve policy attention in rural revitalization strategy. [Display omitted] • This study provides a synthetic evaluation of land consolidation effects on rural revitalization in China. • Land consolidation played more positive than no/negative roles in rural revitalization, with positive cases accounting for 74%. • More positive outcomes were reported significantly in the case of Prosperous Life and Industrial Prosperity. • The positive effects were non-significant in terms of Ecological Livability and Rural Civilization & Effective Governance. [ABSTRACT FROM AUTHOR]

Single crystal CeO2, as a surrogate material to UO2, was irradiated with 500keV xenon ions at 800°C while being observed using in situ transmission electron microscopy (TEM). Experimental results show the formation and growth of defect clusters including dislocation loops and cavities as a function of increasing atomic displacement dose. At high dose, the dislocation loop structure evolves into an extended dislocation line structure, which appears to remain stable to the high dose levels examined in this study. A high concentration of cavities was also present in the microstructure. Despite high atomic displacement doses, the specimen remained crystalline to a cumulated dose of 5×1015 ions/cm2, which is consistent with the known stability of the fluorite structure under high dose irradiation. Kinetic Monte Carlo calculations show that oxygen mobility is substantially higher in hypo-stoichiometric UO2/CeO2 than hyper-stoichiometric systems. This result is consistent with the ability of irradiation damage to recover even at intermediate irradiation temperatures. [ABSTRACT FROM AUTHOR]

Post-irradiation examination (PIE) results of microstructure in irradiated Al-UMo diffusion couples are reported. These diffusion couples were irradiated by 60 MeV Xe ions at four different temperatures up to approximately 5.5 × 1017 ions/cm2 peak ion fluence. An Al-UMo interaction layer (IL) was found to form at all four investigated temperatures. The IL is homogeneously amorphous when formed up to 150 °C. At 215 °C, the (U,Mo)Al 3 nanocrystalline precipitates form within the amorphous IL matrix. Kirkendall voids with prominent temperature dependence were observed in both the Al layer and its interface with the IL. On the other hand, Xe bubbles were found to form in UMo and Al-UMo IL with different morphology. These microstructure features were quantitatively measured and are reported to provide valuable references for understanding the irradiation behavior of UMo/Al dispersion fuel. [ABSTRACT FROM AUTHOR]

Uranium carbides have attracted renewed interest as advanced nuclear fuels for Generation IV reactors. As an important property required for gas bubble modeling in nuclear fuels, the surface energy of uranium carbides is scarce in literature. In this work, we study the surface properties of uranium carbides by first-principles density functional theory calculations. Surface orientations with maximum Miller index up to 3, 2 and 2 are investigated for UC, U 2 C 3 and α-UC 2 , respectively. By studying the effects of surface termination and chemical potential on surface energy, we identify the factors that determines the surface stability. From the calculated surface energies, the surface properties of uranium carbide single crystals are obtained from Wulff construction, including equilibrium morphology, dominant surface orientation and area weighted surface energy. Equilibrium single crystal morphologies of uranium carbides UC, U 2 C 3 and α-UC 2 constructed from the surface energies predicted by first-principles calculations. Image 1 • Surface energies of uranium carbides predicted by first-principles calculations. • Surface morphologies of uranium carbide crystals obtained by Wulff construction. • Surface stability analyzed based on surface termination and chemical potential. [ABSTRACT FROM AUTHOR]

Investment and financing are crucial for the healthy development of modern enterprises. A series of recent studies have examined various influential factors of financial constraints of enterprises, but few researchers have incorporated the influential factors simultaneously. This study introduces the term ecology of finance as a synthesized indicator to measure the influences of a series of variables that may affect financial constraints simultaneously. Using the data of Chinese A-share listed energy- and pollution-intensive firms from 2007 to 2017, how and to what extent the ecology of finance affects financial constraints is quantitatively investigated. The main finding of this research is threefold. First, good internal ecology of finance can relieve the financial constraints of high-polluted and high energy consumption firms, and improved external ecology of finance intensifies the financial constraints. Second, firms with high-level internal ecology of finance are more sensitive to the change in external ecology of finance. Third, firms with a lower level of external ecology of finance are affected more by the change in internal ecology of finance. This study provides insights on how to formulate appropriate policies and regulations for energy- and pollution-intensive companies to relieve their financial constraints and improve their environmental performance. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries show great potential in the field of energy storage because of their high-energy density, but the shuttle effect of lithium polysulfide has seriously hindered their practical process. Quasi-solid-state electrolyte (QPE) is considered to be a promising alternative to traditional liquid electrolyte, which can improve the safety and cycling performance of lithium-sulfur batteries. Herein, a novel poly(vinyl carbonate- co -butyl acrylate) QPE with 3D crosslinked network (PEGDA-P(VCA- co -BA)) is designed to capture lithium polysulfide through a chemical adsorption of abundant ester groups. The PEGDA-P(VCA- co -BA) QPE exhibits high ionic conductivity of 2.9 mS cm−1. In order to synergize the beneficial effect of the PEGDA-P(VCA- co -BA) QPE, the nitrogen-doped carbon nanotube film-supported sulfur/Li cells are assembled with the QPE. As-assembled lithium-sulfur batteries show high initial capacity of 1080 mAh g−1 at 0.1 C, long cycle life (capacity retention of 715 mAh g−1 after 500 cycles) and superior rate performance. [ABSTRACT FROM AUTHOR]

With the penetration of multiple distributed energy sources, demand side management (DSM) of the regional integrated energy system (RIES) becomes more complicated in the energy market. Real-time pricing (RTP) is an effective method for DSM, which can flexibly guide the supply and demand sides to adjust their behavior to participate in demand response (DR). In this paper, a hierarchical energy system is studied including multiple RIESs with multiple energy dispatch and supplement. To maximize the social welfare, a bilevel programming model is developed, in which the upper level aims at maximizing the profits of the supplier, and the lower level aims at maximizing the RIESs' welfare. Then, the proposed bilevel model is transformed into a mixed integer quadratic programming model using duality theory and Karush-Kuhn-Tucker conditions. Furthermore, the RTP strategy is obtained, and the optimal energy scheme of RIES is given in the solution. Compared simulations in different scenarios, the total social welfare is increased by about 14.12%, the peak-to-valley difference of power load and carbon emissions are reduced by 16.99% and 5.7% respectively after DR. The results show that the proposed bilevel model under the RTP is conducive to social economy and environment. • A hierarchical market framework is studied between the main grid and multiple RIESs. • A bilevel programming model is proposed to integrate the RTP and energy dispatch in the RIES. • Besides the operating cost, users' welfare is adopted in the model. • The RTP mechanism based on IDR is designed to balance the supply and demand. • The optimal energy dispatch strategy of the RIES is obtained by using the KKT conditions to transform the bilevel model. [ABSTRACT FROM AUTHOR]

Here synchrotron scattering analysis results on U–7wt.%Mo fuel specimens irradiated in the Advanced Test Reactor to three burnup levels (3.0, 5.2, and 6.3 × 10 21 fission/cm 3 ) are reported. Mature fission gas bubble superlattice was observed to form at intermediate burnup. The superlattice constant was determined to be 11.7 and 12.0 nm by wide-angle and small-angle scattering respectively. Grain sub-division takes place throughout the irradiation and causes the collapse of the superlattice at high burnup. The bubble superlattice expands the U–Mo lattice and acts as strong sink for radiation-induced defects. The evolution of dislocation loops was, therefore, suppressed until the bubble superlattice collapsed. [ABSTRACT FROM AUTHOR]

• Three kinds of honeycomb structures were printed using carbon fiber reinforced composites, and the tensile mechanical properties of honeycomb structures were studied by combining experimental and simulation analysis methods. Finally, the relationship between fracture toughness and fractal dimension of tensile fracture surface is analyzed by fractal theory. The study employed chopped fiber-reinforced nylon composite, referred to as "Onyx," along with continuous carbon fiber materials. Using the material extrusion manufacturing process, three sandwich structures were created: a conventional, a concave hexagonal with negative Poisson's ratio, and a feather-inspired structure. Tensile testing and finite element simulations were conducted to analyze their tensile properties and crack propagation paths under tension. Fractal dimensions were calculated for each structure: the standard structure had a dimension of 1.4626, the bionic feather-inspired was 1.4810, and the negative Poisson's ratio concave hexagonal structure measured 1.4973. [ABSTRACT FROM AUTHOR]

• UV222 suppressed photoreactivation of E. coli by 2-log compared with UV254. • UV222 disinfection damaged multiple cellular targets—DNA, protein, and the cell membrane. • UV222 induced DNA damage at fewer sites than UV254, but the damage was more severe. • UV222 damaged the E. coli cell membrane by photolyzing membrane lipid and protein. • UV222 photolyzed nucleic acid bases and amino acids. Low-pressure mercury lamps emitting at 254 nm (UV254) are used widely for disinfection. However, subsequent exposure to visible light results in photoreactivation of treated bacteria. This study employed a krypton chloride excimer lamp emitting at 222 nm (UV222) to inactivate E. coli. UV222 and UV254 treatment had similar E. coli -inactivation kinetics. Upon subsequent irradiation with visible light, E. coli inactivated by UV254 was reactivated from 2.71-log to 4.75-log, whereas E. coli inactivated by UV222 showed negligible photoreactivation. UV222 treatment irreversibly broke DNA strands in the bacterium, whereas UV254 treatment primarily formed nucleobase dimers. Additionally, UV222 treatment caused cell membrane damage, resulting in wizened, pitted cells and permeability changes. The damage to the cell membrane was mainly due to the photolysis of proteins and lipids by UV222. Furthermore, the photolysis of proteins by UV222 destroyed enzymes, which blocked photoreactivation and dark repair. The multiple damages can be further evidenced by 4.0–61.1 times higher quantum yield in the photolysis of nucleobases and amino acids for UV222 than UV254. This study demonstrates that UV222 treatment damages multiple sites in bacteria, leading to their inactivation. Employing UV222 treatment as an alternative to UV254 could be viable for inhibiting microorganism photoreactivation in water and wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Aims: To analyze the combined impact of the histone deacetylase inhibitor (HDACI) Trichostatin A (TSA) and the extracellular-signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 on gastric cancer (GC) cell line SGC7901 growth. Main methods: SGC7901 cells were treated with TSA, PD98059 or with a TSA-PD98059 combination. Effects of drug treatment on tumor cell proliferation, apoptosis, cell cycle progression, and cell signaling pathways were investigated by MTS assay, flow cytometry, Western blotting, chromatin immunoprecipitation (ChIP) assay, electrophoretic mobility shift assay (EMSA), and luciferase reporter assay, respectively. Key findings: PD98059 enhanced TSA-induced cell growth arrest, apoptosis and activation of p21WAF1/CIP1, but reversed TSA-induced activation of ERK1/2 and nuclear factor-κB (NF-κB). TSA alone up-regulated Notch1 and Hes1, and down-regulated Notch2, but PD98059 did not affect the trends of Notch1 and Notch2 induced by TSA. Particularly, PD98059 did potentiate the ability of TSA to down-regulate phospho-histone H3 protein, but increased levels of the acetylated forms of histone H3 bound to the p21WAF1/CIP1 promoter, leading to enhanced expression of p21WAF1/CIP1 in SGC7901 cells. Significance: PD98059 synergistically potentiates TSA-induced GC growth arrest and apoptosis by manipulating NF-κB and p21WAF1/CIP1 independent of Notch. Therefore, concomitant administration of HDACIs and ERK1/2 inhibitors may be a promising treatment strategy for individuals with GC. [Copyright &y& Elsevier]

Permanganate is a common preoxidant applied in water treatment to remove organic pollutants and to reduce the formation of disinfection by-products. However, the effect of permanganate preoxidation on the transformation of dissolved effluent organic matter (dEfOM) and on the formation of unknown chlorinated disinfection by-products (Cl-DBPs) during chlorination remains unknown at molecular level. In this work, the molecular changes of dEfOM during permanganate preoxidation and subsequent chlorination were characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Permanganate preoxidation was found to decrease the DBE (double bond equivalent) and AI mod (modified aromaticity index) of the dEfOM. The identity and fate of over 400 unknown Cl-DBPs during KMnO 4 -chlorine treatment were investigated. Most Cl-DBPs and the precursors were found to be highly unsaturated aliphatic and phenolic compounds. The Cl-DBPs precursors with lower H/C and lower O/C were preferentially removed by permanganate preoxidation. Additionally, permanganate preoxidation decreased the number of unknown Cl-DBPs by 30% and intensity of unknown Cl-DBPs by 25%. One-chlorine-containing DBPs were the major Cl-DBPs and had more CH 2 groups and higher DBE w than Cl-DBPs containing two and three chlorine atoms. 60% of the Cl-DBPs formation was attributed to substitution reactions (i.e., +Cl–H, +2Cl–2H, +3Cl–3H, +ClO–H, +Cl 2 O 3 –2H). This work provides detailed molecular level information on the efficacy of permanganate preoxidation on the control of overall Cl-DBPs formation during chlorination. [Display omitted] • Permanganate preoxidation led to the decrease of DBE w and AI mod,w in the dEfOM. • More than 400 unknown Cl-DBPs and their fate during KMnO 4 -chlorine treatment were characterized. • The Cl-DBPs and precursors molecular formulas featured with high unsaturation and aromaticity. • Permanganate preoxidation preferentially removed Cl-DBPs precursors with lower H/C and O/C. • 60% of the Cl-DBPs formation was attributed to substitution reactions. [ABSTRACT FROM AUTHOR]

• A welfare expectation model based on bilevel programming is proposed. • A real-time pricing mechanism based on demand response is designed. • Besides the operating cost, users' utility in microgrids are taken to our model. • A hybrid distributed PSO-BBA algorithm is developed to protect the privacy of users. As distributed energy (DE) and storage devices being integrated into microgrids (MGs), demand side management (DSM) is getting more and more complicated. The real-time pricing (RTP) mechanism based on demand response (DR) is an ideal method for DSM, which can achieve supply–demand balance and maximize social welfare in the future. This paper proposes a hierarchical market framework to address RTP between the power supplier and multi-microgrids (MMGs). Firstly, an expectation bilevel model is proposed to adjust the energy scheduling of MMGs, including uncertain loads, multi-energy-supply and storage devices,etc. In the proposed bilevel model, the upper level aims to maximize the profit of the power supplier, while the lower level is formulated to maximize the expectation of total welfares for MMGs. Then, the lower level is transformed into a deterministic optimization problem by mathematical techniques. To solve the model, a hybrid algorithm-called distributed PSO-BBA, is put forward by combining the particle swarm optimization (PSO) and the branch and bound algorithm (BBA). In this algorithm, the PSO and BBA are employed to address the subproblems of upper and lower levels, respectively. Finally, simulations on several situations show that the proposed distributed RTP method is applicable and effective under uncertainties, and can reduce the computational complexity as well. The results show that the hierarchical energy dispatch framework is not only more reasonable but also can increase the profits of power suppliers and the welfare of MGs effectively. [ABSTRACT FROM AUTHOR]

Abstract Dodecyltrimethylammonium chloride (DTAC) is a quaternary ammonium compound (QAC) that is a widespread contaminant in environmental media and therefore of increasing concern. The synergistic effect with UV irradiation and persulfate (UV/PS) was used to degrade DTAC. The removal of DTAC was 91% with the PS dosage of 75.6 μM (UV/PS) and UV fluence of 870 mJ·cm−2. The second-order rate constants of DTAC with HO and SO 4 − were determined to be k HO , DTAC (4.2 ± 0.18) × 109 M−1 s−1 and k SO 4 ∙−, DTAC (2.5 ± 0.27) × 109 M−1 s−1, respectively. The contributions of HO and SO 4 − to DTAC degradation in the UV/PS were found to be 30% and 62% at pH 7, respectively. The contributions of SO 4 − and HO were not significantly influenced by acidic medium (pH 3–pH 7), whereas they were significantly affected by basic medium (pH 7–pH 11). The wastewater matrixes of HCO 3 −, Cl− and humic acid inhibited the DTAC elimination, whereas NO 3 − and SO 4 2− had no significant impact on its elimination. Moreover, the k obs,DTAC in the reverse osmosis influent (ROI) and reverse osmosis concentrate (ROC) were examined to be 0.04 to 0.1 min−1 and 0.02 to 0.05 min−1, respectively, as the PS dosage increased from 18.9 to 113.4 μM. The inhibitive effects of matrix in ROI and ROC was 70% and 81%, respectively. The contribution of radical scavenging effect by matrix ROI and ROC was more significant to DTAC degradation than UV scattering effect in ROI and ROC matrices. A UV fluence of 1305 mJ·cm−2 was necessitated for complete detoxification and DTAC solution by UV/PS. Graphical abstract Unlabelled Image Highlights • UV/PS oxidation can significantly degrade dodecyltrimethylammonium chloride (DTAC). • Reaction rate constants of DTAC with HO and SO 4 − were (4.2 ± 0.18) × 109 and (2.5 ± 0.27) × 109 M−1 s−1. • The generated HO and SO 4 − were comprised dominant radical species during UV/PS oxidation under neutral condition. • Acute toxicity of DTAC solution treated by UV/PS is completely detoxified. [ABSTRACT FROM AUTHOR]

Abstract After treated wastewater is discharged into surface water for unplanned indirect potable reuse, solar irradiation transforms the dissolved organic matter (DOM), which would alter the formation of disinfection byproducts (DBPs) and change the cytotoxicity formation potential (CtFP) during post–chlorination in drinking water treatment plants. This study investigated the effects of solar irradiation on the CtFP and total organic halogen formation potential (TOXFP) of wastewater during post–chlorination. Exposure to natural sunlight decreased the formation potential of cytotoxicity to Chinese Hamster Ovary cells. Under 24 h simulated solar irradiation, CtFP and TOXFP decreased by more than 40%. X–ray photoelectron spectra and Fourier transformation infrared spectra suggested solar irradiation destroyed the key DBP precursors containing phenolic hydroxyl moieties (Ph–OH). The destruction of Ph–OH under solar irradiation was reflected by a decrease in the electron donating capacity (EDC) of DOM and the post–chlorination decreased the EDC further. Increasing the irradiation–consumed EDC abated the chlorine–consumed EDC, while the chlorine–consumed EDC was positively correlated to the CtFP and TOXFP by means of the electrophilic substitution–aromatic ring cleavage. Solar irradiation thus reduced the CtFP and TOXFP in wastewater during post–chlorination. This study revealed that solar irradiation decreased the risks of treated wastewater for unplanned indirect potable reuse and provided a strategy of controlling CtFP and TOXFP via reducing EDC of DOM in pretreatments. Graphical abstract Image 1 Highlights • Solar irradiation reduces the CtFP of wastewater during post chlorination. • Solar irradiation destroyed the phenolic hydroxyl moieties of DOM in wastewater. • Solar irradiation reduces the chlorine–consumed EDC of DOM during post chlorination. • Chlorine–consumed EDC correlates to the formation potential of cytotoxicity and TOX. [ABSTRACT FROM AUTHOR]

A mesoscale model is developed by integrating the rate theory and phase-field models and is used to study the fission-induced recrystallization in U-7Mo alloy. The rate theory model is used to predict the dislocation density and the recrystallization nuclei density due to irradiation. The predicted fission rate and temperature dependences of the dislocation density are in good agreement with experimental measurements. This information is used as input for the multiphase phase-field model to investigate the fission-induced recrystallization kinetics. The simulated recrystallization volume fraction and bubble-induced swelling agree well with experimental data. The effects of the fission rate, initial grain size, and grain morphology on the recrystallization kinetics are discussed based on an analysis of recrystallization growth rate using the modified Avrami equation. We conclude that the initial microstructure of the U-Mo fuels, especially the grain size, can be used to effectively control the rate of fission-induced recrystallization and therefore swelling. [ABSTRACT FROM AUTHOR]

U–Mo metallic alloys have been extensively used for the Reduced Enrichment for Research and Test Reactors (RERTR) program, which is now known as the Office of Material Management and Minimization under the Conversion Program. This fuel form has also recently been proposed as fast reactor metallic fuels in the recent DOE Ultra-high Burnup Fast Reactor project. In order to better understand the behavior of U–10Mo fuels within the fast reactor temperature regime, a series of annealing and characterization experiments have been performed. Annealing experiments were performed in situ at the Intermediate Voltage Electron Microscope (IVEM-Tandem) facility at Argonne National Laboratory (ANL). An electro-polished U–10Mo alloy fuel specimen was annealed in situ up to 700 °C. At an elevated temperature of about 540 °C, the U–10Mo specimen underwent a relatively slow microstructure transition. Nano-sized grains were observed to emerge near the surface. At the end temperature of 700 °C, the near-surface microstructure had evolved to a nano-crystalline state. In order to clarify the nature of the observed microstructure, Laue diffraction and powder diffraction experiments were carried out at beam line 34-ID of the Advanced Photon Source (APS) at ANL. Phases present in the as-annealed specimen were identified with both Laue diffraction and powder diffraction techniques. The U–10Mo was found to recrystallize due to thermally-induced recrystallization driven by a high density of pre-existing dislocations. A separate in situ annealing experiment was carried out with a Focused Ion Beam processed (FIB) specimen. A similar microstructure transition occurred at a lower temperature of about 460 °C with a much faster transition rate compared to the electro-polished specimen. [ABSTRACT FROM AUTHOR]

Although microplastic (MP) pollution has been defined as a new global challenge by the United Nations Environment Programme, their abundance and composition has only been studied in-depth within farmland soil, while minimal attention has been placed on urban soil contamination. Accordingly, within the current study, MP abundance and composition is investigated within urban soil from green spaces in Nanjing, eastern China. The average MP abundance in soil was 461 ± 222 items/kg and primarily comprised fibers (39.1%) and fragments (37.7%). MPs <1000 μm in size accounted for 83.7% of the total content and white MPs were the most abundant (26.5%). The dominant polymers were polyethylene glycol terephthalate (32.0%) and polypropylene (20.5%). Moreover, relationship network analysis generated three distinct MP modules based on community similarity. Indeed, the degree of similarity increased by ∼26.8% per kilometer. Furthermore, application of a forward selective optimal multiple regression model identified clay, sand, longitude, and points of interest for recycling bins (RecyclePOI) as the primary spatial and soil environmental factors affecting MP abundance and composition. Additionally, five potential sources of MPs were identified based on the MP diversity integrated index fitting results, and point of interest density (MDII-POI) source analysis (R 2 = 0.21–0.62; P < 0.05). In particular, the point of interest of express delivery points (ExpressPOI) were important sources of plastic emissions as they are widely distributed throughout urban and fringe areas. Collectively, the findings of this study provide novel insights regarding quantitative source appointment and regional ecological control of MPs in urban soil. [Display omitted] • MP pollution of urban soil in Nanjing was investigated for the first time. • Relationship networks revealed the difference and modularity of MP communities. • Occurrence of MPs was result of interactions between source-sink factors. • Five types of sources were isolated based on MDII-POI source appointment. [ABSTRACT FROM AUTHOR]

This study compared transdermal aconitine delivery using solid lipid nanoparticles ( SLN) and microemulsion ( ME) vehicles. Aconitine-loaded SLN and ME were formulated with the same surfactant, cosurfactant, and water content, with an equal amount of oil matrix ( ATO 888 for SLN and ethyl oleate for ME). These nanosized formulations (70-90 nm) showed suitable p H values and satisfactory skin tissue biocompatibility. SLN contained a higher concentration of smaller nanoparticles, compared with that in ME. Neither of the nanocarriers penetrated across excised skin in their intact form. In vitro transdermal delivery studies found that transdermal aconitine flux was lower from SLN than from ME ( p < 0.05), but skin aconitine deposition was higher using SLN ( p < 0.05). Fluorescence-activated cell sorting indicated that in vitro uptake of fluorescently labeled SLN by human immortalized keratinocyte ( Ha Ca T) cells was greater than that of ME, indicating that a transcellular pathway may contribute to cutaneous drug absorption more effectively from SLN. In vivo studies found that these formulations could loosen stratum corneum layers and increase skin surface crannies, which may also enhance transdermal aconitine delivery. SLN produced a more sustained aconitine release, indicating that compared with ME, this transdermal delivery vehicle may reduce the toxicity of this drug. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:3602-3610, 2014 [ABSTRACT FROM AUTHOR]

In this study, it was found that monochloramine induced the formation of reactive species during ozonation of chloromethylisothiazolinone (CMIT). CMIT was found recalcitrant to chloramine. However, chloramine promoted the degradation of CMIT by ozonation significantly. Hydroxyl radicals contributed most to CMIT degradation (87%) during ozone/chloramine synergistic oxidation process (SOP). The hydroxyl radical exposure during ozone/chloramine SOP was around 7.9 times higher than that of ozonation process. The hydroxyl radical yield of ozone/chloramine SOP was estimated to be 32%. The reaction mechanisms between ozone and chloramine were postulated to include the oxygen transfer reaction to form singlet oxygen, and the formation of hydroxyl radical by the insertion pathway or electron transfer pathway. Chloramine dosage and pH are essential influencing factors. The degradation of CMIT increased from 41% to 74% with increasing chloramine dosage (0–20 μM), and then decreased to 65% when chloramine dosage continually increased to 40 μM. Ozone/chloramine SOP showed better performance at acidic or neutral conditions than basic condition. Based on the intermediates identified, the degradation pathway of CMIT during ozone/chloramine SOP included the oxidation of sulfur atom and the substitution of chlorine group by hydroxyl group. The oxidation of sulfur atom induced lower toxicities of transformation products. The toxicities of hydroxylation products were lower to fish and algae, but higher to daphnia. Based on the GC-ECD results, only trichloromethane (1.94 μg/L) was detected after ozone/chloramine SOP, accounting for 0.17% (μM/μM) of the CMIT removal. Unlabelled Image • The combination of ozone and chloramine showed synergistic effects for CMIT removal. • The hydroxyl radical yield of the ozone/chloramine process was 32%. • Chloramine dosage and pH affected ozone/chloramine oxidation of CMIT. • Degradation pathway of CMIT by ozone/chloramine oxidation was proposed. [ABSTRACT FROM AUTHOR]

Here, we report the first direct thermal conductivity measurement results for Al–UMo interaction layer (IL), which is typically observed in UMo/Al dispersion fuel plates under irradiation. The investigated IL was formed by irradiating Al coated UMo substrate using 80 MeV iodine ions at 180∘C up to 3.03 × 1017 ions/cm2 fluence. Microstructural characterization indicated that the induced IL is amorphous with an approximately (U 0.8 ,Mo 0.2)Al 5.3 stoichiometry, which is similar to that formed under in-pile irradiation. Focused ion beam (FIB) was used to prepare nine specimens of various lengths from the IL that could be suspended across a microfabricated device for thermal conductivity measurement. The measured thermal conductivity values of the IL were significantly lower than the values for both the original UMo fuel and the Al. The successful measurement of the Al–UMo IL provides valuable information for the development and qualification of UMo/Al dispersion fuels for research and test reactor conversion applications, and further demonstrates the promising capabilities of utilizing the suspended bridge method in nuclear fuel research. [ABSTRACT FROM AUTHOR]

• Molecular weight (MW) distribution of electron-donating moiety (EDM) was evaluated. • MW fraction of 1.8–6.9 k Da accounted the majority of EDM in natural DOM. • MW fraction of <1 k Da accounted the majority of EDM in DOM of wastewater effluent. • The heterogeneous MW distribution of EDM in DOM is related to that of UVA254. • Relative decreases of EDM and UVA indicated the oxidation pathways for MW fractions. Electron-donating moieties (EDM) have recently been used to characterize the redox properties and treatability of dissolved organic matter during water and wastewater treatment. In this study, size exclusion chromatography followed by a derivatization-spectrometric method was developed to determine the molecular weight (MW) distribution of EDM in dissolved organic matter. The relationships between EDM concentration and chromophore content (indicated by UVA 254), fluorophore content (indicated by fluorescence), and dissolved organic carbon (DOC) concentration were analyzed for different MW fractions. In general, natural organic matter (NOM) showed higher total EDM concentration and higher EDM average MW than effluent organic matter (EfOM). For NOM, fractions with MW between 1.8 k and 6.9 k Da accounted for most of the EDM (45.4%–48.6%), followed by the fractions with MW < 1.8 k Da (25.6%–42.4%). By contrast, the EDM in EfOM occurred predominantly in fractions with MW < 1 k Da (51.8%–58.6%), with lower concentrations in fractions with MW > 1.8 k Da (<20.2%). The heterogeneous MW distribution of EDM was strongly correlated to the presence of chromophores, but not DOC or fluorophores. The EDM difference between MW fractions suggested that the fraction with MW 1.8–6.9 k Da (40.7%–47.1%) and the fractions with MW < 1 k Da (50.2%–58.8%) should be the dominant oxidant consumers in NOM and EfOM, respectively. When the EDM was normalized by the DOC for each MW fraction (EDM MW /DOC MW), the EDM MW /DOC MW of relatively high-MW fractions (>1.8 k Da) is 1.2–1.9 times of relatively low-MW (<1 k Da) fractions for both NOM and EfOM, which indicates that higher-MW fractions are more susceptible to chemical oxidations. The relationship between EDM change and UVA 254 change varied for different MW fractions during advanced ozonation treatment, because of the different oxidation mechanisms in operation for MW fractions. The ozonation of EfOM fractions with higher MW (>1.8 k Da) and lower MW (<1 k Da) preferentially resulted in benzoquinone formation and ring-cleavage, respectively. [ABSTRACT FROM AUTHOR]