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Aluminum/tetrahydrodicyclopentadiene/oleic acid (Al/JP-10/OA) nanofluid fuel is considered a potential fuel for aircraft powered by aviation turbine engines. However, an optimized formula for an Al/JP-10/OA system inducing a secondary atomization and micro-explosion effect and improving the burning performance needs to be developed. With this aim, in this work, the combustion characteristics of pure JP-10, JP-10/OA, JP-10/Al, and Al/JP-10/OA were experimentally tested, and a comparative analysis was conducted. Specifically, the influence of the surfactant and nanoparticle concentrations on the combustion characteristics of Al/JP-10/OA nanofluid fuel, including the flame structure, the flame temperature, the burning rate, the secondary atomization and micro-explosion effect, etc., were evaluated in detail. The results demonstrate that the addition of OA surfactant and Al nanoparticles had a significant effect on the burning rate of fuel droplets. The OA had an inhibition effect, while the Al nanoparticles had a promotion effect. As both OA and Al nanoparticles were added to the JP-10, the synergetic effect had to be considered. At the optimum ratio of OA to Al for the best suspension stability, there is a critical Al concentration of 1.0 wt.% from promotion to inhibition with increases in the Al concentration. The addition of OA and Al nanoparticles induced the secondary atomization and micro-explosion, resulting in an unsteady combustion and chaotic flame structure. The transient flame temperature of hundreds of Kelvins increased, the high-temperature flame zone widened, and thus, the energy release was elevated. Therefore, the combustion performance and energy release of Al/JP-10/OA nanofluid fuel can be improved through the secondary atomization and micro-explosion effect induced by the surfactant and nanoparticles. [ABSTRACT FROM AUTHOR]

Conjugated polymers have attracted extensive attention in numerous research fields because of their exceptional photoelectric properties and distinctive solution processing capabilities. The conformation of the chain and the structure of the condensed state in solution are closely related to various factors, such as concentration and solvent. Concentration, as a significant external parameter, plays a crucial role in the self‐assembly and formation of crystalline structures in conjugated polymers. It also affects the properties of the solution, the structure of the membrane, and the performance of the fabricated devices. Recently, there have been an increasing number of studies conducted from the perspective of solution concentration. Therefore, it is important to comprehensively summarize the effect of concentration on the transition process of chain structure from solution to film, as well as the impact of concentration on the performance of related devices. In this review, we summarize the effects of concentration on the chain motion, particle size, ordered structure, and photoelectric properties of conjugated polymers in solutions and thin films, as well as on device efficiency. This provides a unique perspective on the fundamental characteristics of conjugated polymers, which can assist in the development and improvement of optoelectronic devices. [ABSTRACT FROM AUTHOR]

This work involves an experimental study of the thermophysical properties of hybrid nanofluids of TiO2 and graphene in a binary mixture of water and ethylene glycol. Hybrid nanofluid samples with different volume fractions (0.05-2.5%) were prepared by dispersing equal volumes of TiO2 and graphene nanoparticles in a binary mixture of water and ethylene glycol in the ratio of 50-50% by volume. The thermal conductivity, surface tension, and dynamic viscosity of the hybrid nanofluids were measured at temperatures ranging from 253 K to 303 K. The experimental results showed that the low concentration samples exhibited shear thinning non-Newtonian behavior, while the high concentration samples exhibited shear thickening non-Newtonian behavior. The measurements showed that the thermal conductivity of the nanofluids increases by up to 41.93% with increasing nanoparticle concentration and temperature. The surface tension improves by 43.61%, 39.77%, and 51.98% at concentrations of 2.5%, 2%, and 2% by volume at temperatures of 258.15 K, 268.15 K, and 283.15 K, respectively. In terms of aircraft deicing fluid performance, the addition of TiO2 and graphene nanoparticles at less than 0.5% by volume contributes to the improvement of aircraft deicing fluid performance.

The phase state, electrical conductivity and magnetoresistive properties of binary film alloys based on Fe, Co and Ni prepared by the method evaporation in high vacuum in the temperature range 100700 K have been studied. It has been shown that the fcc-phase is observed for as-deposited and annealed up to 700 K Fe0,50Ni0,50 thin films with a thickness d 10100 nm, the fcc-phase is observed. For Fe0,67Ni0,33 Fe0,50Co0,50 and Fe0,67Co0,33 thin films, the bcc-phase is fixed. It was found that the size dependences of the resistivity, temperature coefficient of resistance and magnetoresistance are realized for all structurally continuous film alloys. The character of size dependences is а like the corresponding dependences for the pure metal films. It has been shown that for Fe0,67Ni0,33, Fe0,50Co0,50 and Fe0,67Co0,33 the size dependences of both longitudinal and transverse magnetoresistance appear much weaker than for Fe0,50Ni0,50 thin alloy. For Fe0,67Ni0,33, Fe0,50Co0,50 and Fe0,67Co0,33 thin alloys, the value of both longitudinal and transverse magnetoresistance is weakly depending on the temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • The catalytic effect of bismuth on Pt(1 0 0) electrodes for the FAOR is linked to the Pt-Bi ensembles. • Bismuth catalyzes the direct path and inhibits the CO formation route. • A mechanism for the reaction that accounts for the experimental results is proposed. The formic acid oxidation reaction (FAOR) on bismuth-modified Pt(1 0 0) is studied using electrochemical techniques and FITR spectroscopy at different bismuth coverages and formic acid concentrations. The results clearly show that: (1) The measured currents for the Bi-modified Pt(1 0 0) surface contain contributions from both the Pt-Bi ensembles and the Pt sites far from the Bi adatoms. (2) The catalytic effect of bismuth is not linked to the adsorption of formate on Pt sites. (3) The bismuth not only improves the activity of the FAOR through the active intermediate but also inhibits the CO poison by a third-body effect. (4) The experimental results indicate that the catalytic activity is linked to the Pt-Bi ensembles. The active species, formate, adsorbs on the Bi site and the neighboring Pt sites facilitate the cleavage of the C–H bond. (5) From the concentration dependence, the reaction order for formate on bismuth-modified Pt(1 0 0) is 1 at low potentials. In contrast, a reaction order of 0.5 is obtained at higher potentials. These results are in agreement with the proposed mechanism. [ABSTRACT FROM AUTHOR]

Aluminum/tetrahydrodicyclopentadiene/oleic acid (Al/JP-10/OA) nanofluid fuel is considered a potential fuel for aircraft powered by aviation turbine engines. However, an optimized formula for an Al/JP-10/OA system inducing a secondary atomization and micro-explosion effect and improving the burning performance needs to be developed. With this aim, in this work, the combustion characteristics of pure JP-10, JP-10/OA, JP-10/Al, and Al/JP-10/OA were experimentally tested, and a comparative analysis was conducted. Specifically, the influence of the surfactant and nanoparticle concentrations on the combustion characteristics of Al/JP-10/OA nanofluid fuel, including the flame structure, the flame temperature, the burning rate, the secondary atomization and micro-explosion effect, etc., were evaluated in detail. The results demonstrate that the addition of OA surfactant and Al nanoparticles had a significant effect on the burning rate of fuel droplets. The OA had an inhibition effect, while the Al nanoparticles had a promotion effect. As both OA and Al nanoparticles were added to the JP-10, the synergetic effect had to be considered. At the optimum ratio of OA to Al for the best suspension stability, there is a critical Al concentration of 1.0 wt.% from promotion to inhibition with increases in the Al concentration. The addition of OA and Al nanoparticles induced the secondary atomization and micro-explosion, resulting in an unsteady combustion and chaotic flame structure. The transient flame temperature of hundreds of Kelvins increased, the high-temperature flame zone widened, and thus, the energy release was elevated. Therefore, the combustion performance and energy release of Al/JP-10/OA nanofluid fuel can be improved through the secondary atomization and micro-explosion effect induced by the surfactant and nanoparticles.

This work involves an experimental study of the thermophysical properties of hybrid nanofluids of TiO2 and graphene in a binary mixture of water and ethylene glycol. Hybrid nanofluid samples with different volume fractions (0.05-2.5%) were prepared by dispersing equal volumes of TiO2 and graphene nanoparticles in a binary mixture of water and ethylene glycol in the ratio of 50-50% by volume. The thermal conductivity, surface tension, and dynamic viscosity of the hybrid nanofluids were measured at temperatures ranging from 253 K to 303 K. The experimental results showed that the low concentration samples exhibited shear thinning non-Newtonian behavior, while the high concentration samples exhibited shear thickening non-Newtonian behavior. The measurements showed that the thermal conductivity of the nanofluids increases by up to 41.93% with increasing nanoparticle concentration and temperature. The surface tension improves by 43.61%, 39.77%, and 51.98% at concentrations of 2.5%, 2%, and 2% by volume at temperatures of 258.15 K, 268.15 K, and 283.15 K, respectively. In terms of aircraft deicing fluid performance, the addition of TiO2 and graphene nanoparticles at less than 0.5% by volume contributes to the improvement of aircraft deicing fluid performance. [ABSTRACT FROM AUTHOR]

We review and analyse the literature data on the experimental results dealing with the crystal structure, phase state, and magnetoresistive properties of nanostructured thin-film systems based on NixFe1–x permalloy and noble metals prepared by the methods of co-evaporation and layer-by-layer condensation. As shown, regardless of preparation methods, the phase state of systems stays as two-phase one. Upon high-temperature annealing, the formation of solid solutions is possible. As shown, in the case of applying of layer-by-layer condensation method, the value of the magnetoresistive effect depends on the thickness of the magnetic and nonmagnetic layers. In the case of applying the co-evaporation method, the determining parameters are the concentrations of the components and the total thickness of the system. The annealing-temperature effect on magnetoresistive properties of nanostructured thin-film systems based on permalloy and noble metals is analysed.

With the emergence of new psychoactive substances (NPSs) over the years, the substances detected on stamps (also known as blotter papers) have also evolved from the traditional drug—lysergic acid diethylamide (LSD) to the multiple variants of lysergamides such as ALD‐52 and 1P‐LSD. The analysis of such blotter papers is usually done by solvent extraction followed by identification using gas chromatography–mass spectrometry (GC‐MS). This study has shown that hydrolysis to form LSD was observed in GC‐MS analysis when ALD‐52 was extracted with methanol. The extraction of ALD‐52 using other solvents such as acetonitrile, ethanol, isopropyl alcohol, ethyl acetate, and acetone, followed by GC‐MS analysis, was investigated. It is shown that alcoholic solvents such as methanol and ethanol will result in the conversion of ALD‐52 to LSD during GC‐MS analysis, whereas the sterically hindered isopropyl alcohol will prevent this conversion. Investigation also shows that the hydrolysis of ALD‐52 to LSD occurs at the GC injector port. It was also observed that the degree of hydrolysis was more pronounced at a lower concentration (0.1 mg/mL). The study was extended to a close analog—1P‐LSD, and the results showed that 1P‐LSD similarly hydrolyzes to LSD. However, 1P‐LSD was observed to be more stable than ALD‐52 due to steric hindrance because of the propanoyl group. [ABSTRACT FROM AUTHOR]

This study provides an overview of Building-Integrated Wind Turbines, focusing on cement silos as wind concentrators, along with determining the amount of power that could be connected without regard to wind direction. The motivation of this research is the intermittency issue of wind stream in an open environment and non-exploration of wind turbines between cement silos. Building-Augmented Wind Turbines provide 717 W of aerodynamic power at 16 m/s, whereas Standalone Wind Turbines produce 562 W. This is due to the wind speed acceleration between buildings, which causes a concentration effect. Meanwhile, using the simulation software ANSYS, the turbine geometry is developed utilising a Computational Fluid Dynamics evaluation. [ABSTRACT FROM AUTHOR]

In this study, the complexity of sodium ascorbate as a reducing reagent for copper by executing reactions with different ascorbate concentrations at 30°C and a copper concentration at 5 mM was emphasized. It was found that increasing the molar ratio of nascorbate/nCu2+ from 1:1 to 10:1 prolonged the time for the completion of the reduction from 30 to 300 min, respectively. The reactions were investigated by the cyclic voltammetry method and the products were characterized by scanning electron microscopy and X-ray diffraction analyses. The synthesized materials obtained with molar ratios of 1:1 and 10:1 were composed of 55.47% Cu + 44.53% Cu2 O (labeled as As1) and 73.66% Cu + 26.34% Cu2 O (labeled as As10), respectively. Both products were tested for their ability to discolor Basic Red 29 via the Fenton reaction. The discoloration of the dye was more rapid with As1, due to the higher Cu2 O content. [ABSTRACT FROM AUTHOR]

Alpha(α)‐synuclein is closely related to the pathogenesis of Parkinson's disease (PD). The NACore, a fragment of α‐synuclein, is considered to be the key region of α‐synuclein that causes PD. The aggregation dynamics of NACores are studied via coarse‐grained molecular dynamics simulations. We find that NACores can self‐assemble into a large cluster at high concentrations. The aggregation dynamics can be divided into three stages. The growth kinetics for the first and second stages follows the power law, Smax ~ tγ, with the second stage faster than the first one. The characteristic lifetime for the high concentration is 40 times larger than that for the low concentration, implying the low fluidity. Understanding the aggregation dynamics of NACores is helpful to develop drugs for therapeutic prevention and intervention. [ABSTRACT FROM AUTHOR]

In the preparation of polyammonium resin by polycondensation of equimolar amounts of epichlorohydrin and 1,3-bis(dimethylamino)propanol-2 in aqueous solutions, a nonstandard concentration effect was revealed, which manifested itself in a sharp increase in the reduced reaction rate, equilibrium conversion, and achievable molecular weight of the polymer at initial concentrations of reagents close to 2.0 mmol/g (the concentration range of 0.5–3.5 mmol/g was studied). The data obtained can be used in the search for additional economical resources to improve the technical and economic indicators of organic synthesis processes. [ABSTRACT FROM AUTHOR]

This work investigated the photoluminescence behaviour of Tb3+ doped BiPO4 nanophosphors synthesised by co-precipitation method using ethylene glycol. The prepared nanophosphors were characterised by XRD, SEM, FT-IR and PL spectroscopy techniques. Monoclinic phase was observed from the XRD and FT-IR studies. SEM image showed agglomeration of nanoparticles. In the emission spectra, band originated from 3P1–1S0 transition of Bi3+ ion and bands due to 5D4 → 7F6,5,4,3 transitions of doping Tb3+ ion were observed upon excitation at 351 nm. The emission intensity was found to accentuate with the increase in Tb3+ ion concentration upto 3at. % and subsequently attenuated with further increase in Tb3+ ion concentration due to concentration quenching effect. The decay time of the prepared phosphors was also investigated. The CIE chromaticity diagram revealed a nearly white colour emission upon excited at 351 nm. It is possible that the prepared phosphors may be useful for solid-state lighting. [ABSTRACT FROM AUTHOR]

Veterinary antibiotics are increasingly used in the livestock industry annually. Sulfonamides introduced into the soil with manure are usually largely degraded in various pathways. However, the influence of the metabolic intermediate of sulfonamides on nitrogen (N) cycling under anaerobic conditions in soils has been overlooked. To this end, we carried out a microcosm experiment to investigate the potential consequences of ADPD (2-amino-4,6-dimethylpyrimidine, a degradation product of sulfonamide) at five concentration gradients (i.e., 0, 0.01, 0.1, 1, and 10 mg kg−1) on nitrous oxide (N 2 O) emissions, associated genes involved in N cycling, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) in soils applied with manure or urea. The results showed that ADPD application promoted N 2 O emissions under flooded conditions at environmentally relevant concentrations, and the maximum cumulative N 2 O emissions were observed at 1 mg kg−1 and 0.1 mg kg−1 ADPD for manure and urea applied, respectively. The main reasons were the imbalance of denitrifying bacteria, which affected N 2 O production and reduction, and the increase of antibiotic resistance in soil bacteria. In conclusion, these findings contribute to assessing the eco-environmental risks associated with the prevalence of sulfonamide metabolic intermediates and expand our understanding of the link between antibiotics and N transformation. Further research in the field is warranted to incorporate their recommendations into the greenhouse gas assessment system. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) can be considered as a sterilant or a green propellant. For a common use in industrial application, spray is an effective method to form fine H2O2 droplets. In this paper, electrostatic atomization based on the configuration of needle ring electrodes is proposed to produce H2O2 spray by minimizing its effective surface tension. The breakup performances of H2O2 ligaments can be improved by increasing the electric field intensity, reducing the nozzle size, and adjusting suitable volume flow rate. The smallest average diameter of breakup droplets for 35 wt. % concentration H2O2 solution reached 92.8 μm under optimum operation conditions. The H2O2 concentration significantly influenced the breakup performance owing to the concentration effect on comprehensive physical properties such as density, surface tension, viscosity, and permittivity. The average diameters of breakup droplets decreased with decreasing H2O2 concentration. At 8 wt. % concentration, the average breakup droplet diameter was reduced to 67.4 μm. Finally, electrostatic atomization mechanism of H2O2 solution was analyzed by calculating dimensionless parameters of Re, We, and Oh numbers with the combination of the operation conditions and physical properties for in-depth understanding the breakup behaviors. The calculation showed that the minimum average diameter of breakup droplets was obtained at 8 wt. % concentration at the investigated range of H2O2 concentration, which kept in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Simple Summary: The number of insects that feed on an individual tree can be influenced by the growth of leaves during the season, the size of the tree, genetic traits that affect leaf quality, and by the tree species that surround it. To estimate the relative importance of these processes, we determined the date on which leaves start unfolding in spring, trunk diameter, genotype, and neighbourhood of sessile oak trees, and sampled their caterpillar communities. We found that free-living caterpillars were less abundant on older leaves. Caterpillars were less diverse and experienced higher parasitism on larger trees. Leaf-mining casebearers were more abundant on trees that were genetically more homozygous. However, genome size was not important for any guild. In contrast to most previous studies, oaks surrounded by distantly related tree species tended to have higher caterpillar densities. Neighbourhoods were also related to species composition and diversity, but not to the average wingspans or specialization of species. Common species were less abundant on trees with high parasitism rates. Our results suggest that trees are not always better off in diverse forests, as large trees surrounded by distantly related species might actually suffer more insect damage. Communities of herbivorous insects on individual host trees may be driven by processes ranging from ongoing development via recent microevolution to ancient phylogeny, but the relative importance of these processes and whether they operate via trophic interactions or herbivore movement remains unknown. We determined the leaf phenology, trunk diameter, genotype, and neighbourhood of sessile oak trees (Quercus petraea), and sampled their caterpillar communities. We found that leaf development across a time period of days related to free-living caterpillars, which disappeared with leaf age. Tree growth across decades is related to increased parasitism rate and diversity of herbivores. The microevolution of oak trees across millennia is related to the abundance of leaf-mining casebearers, which is higher on more homozygous oaks. However, oak genome size was not important for any guild. In contrast to most previous studies, the phylogenetic distance of oaks from their neighbours measured in millions of years was associated with higher abundances of entire caterpillar guilds. Furthermore, on trees surrounded by only distantly related tree species, parasitism tended to be lower. Lower parasitism, in turn, was associated with higher abundances of codominant caterpillar species. Neighbourhoods and traits of trees were also related to community composition and diversity, but not to the average wingspans or specialization of species, consistent with the assembly of herbivore communities being driven by leaf traits and parasitism pressure on trees rather than by insect movement among trees. However, movement in rarer species may be responsible for concentration effects in more phylogenetically distant neighbourhoods. Overall, we suggest that the assembly of insects on a tree is mostly driven by trophic interactions controlled by a mosaic of processes playing out over very different time scales. Comparisons with the literature further suggest that, for oak trees, the consequences of growing amongst distantly related tree species may depend on factors such as geographic region and tree age. [ABSTRACT FROM AUTHOR]

Bottom-up construction of highly complex architecture from simple components remains one of the long-standing challenges in chemistry. Herein two supramolecular isomers based on large trigonal prismatic Pd3L16 building block are reported. Significantly, they can be controllably obtained by adjusting the solute concentration during crystal growth. Specifically, the square shape crystals, α-[Pd3L16](PF6)12 in the cubic system with I 4 ¯ 3 m space group, can be isolated from a high-concentration solution of Pd3L16. Interestingly, a mesoporous cage assembled from eight Pd3L16 units with a diameter of 24 Å is observed in the crystal structure. For the low-concentration solution of Pd3L16, the rectangular shape crystals β-[Pd3L16](PF6)12 are obtained, which crystallize in the hexagonal system with P63Im space group, and display two-dimension packing pattern and one-dimension mesoporous channels (diameter ca. 22 Å) along the c axis. Moreover, the two supramolecular isomers were used as nanoporous reactors to induce the specific formation of polyiodides with different compositions and shapes as evidenced from single crystal X-ray diffraction studies. These findings provide a reference in targeting functional crystalline mesoporous supramolecular materials from a single complex building unit. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Environmentally persistent free radicals (EPFRs) are emerging pollutants stabilized on or inside particles. Although the toxicity of EPFR-containing particles has been confirmed, the conclusions are always ambiguous because of the presence of various compositions. A clear dose–response relationship was always challenged by the fact that the concentrations of these coexisted components simultaneously changed with EPFR concentrations. Without these solid dose–response pieces of evidence, we could not confidently conclude the toxicity of EPFRs and the description of potential EPFR risks. In this study, we established a particle system with a fixed catechol concentration but different reaction times to obtain particles with different EPFR concentrations. Caenorhabditis elegans (C. elegans) in response to different EPFR concentrations was systematically investigated at multiple biological levels, including behavior observations and biochemical and transcriptome analyses. Our results showed that exposure to EPFRs disrupted the development and locomotion of C. elegans. EPFRs cause concentration-dependent neurotoxicity and oxidative damage to C. elegans , which could be attributed to reactive oxygen species (ROS) promoted by EPFRs. Furthermore, the expression of key genes related to neurons was downregulated, whereas antioxidative genes were upregulated. Overall, our results confirmed the toxicity from EPFRs and EPFR concentration as a rational parameter to describe the extent of toxicity. EPFRs are ubiquitously formed in both high-temperature systems and ambient environment matrices. Although previous studies have demonstrated the toxicity of EPFR-containing particles, a clear dose–response relationship was always challenged by the fact that the concentrations of these co-existed components simultaneously changed with EPFR concentrations. This study compared the toxic impacts of particles with various EPFR concentrations, and demonstrated that EPFRs caused concentration-dependent neurotoxicity and oxidative damage to C. elegans. The results of this study confirmed the dose–response evidences of EPFRs and provided significant information for description the potential environmental risks of EPFRs. [Display omitted] • EPFR-containing particles with various EPFR concentrations were established. • Exposure to EPFRs disrupted the development and locomotion of C. elegans. • EPFRs cause concentration-dependent neurotoxicity and oxidative damage. • The expression of key genes related to neurons was downregulated, whereas antioxidative genes were upregulated. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) can be considered as a sterilant or a green propellant. For a common use in industrial application, spray is an effective method to form fine H2O2 droplets. In this paper, electrostatic atomization based on the configuration of needle ring electrodes is proposed to produce H2O2 spray by minimizing its effective surface tension. The breakup performances of H2O2 ligaments can be improved by increasing the electric field intensity, reducing the nozzle size, and adjusting suitable volume flow rate. The smallest average diameter of breakup droplets for 35 wt. % concentration H2O2 solution reached 92.8 μm under optimum operation conditions. The H2O2 concentration significantly influenced the breakup performance owing to the concentration effect on comprehensive physical properties such as density, surface tension, viscosity, and permittivity. The average diameters of breakup droplets decreased with decreasing H2O2 concentration. At 8 wt. % concentration, the average breakup droplet diameter was reduced to 67.4 μm. Finally, electrostatic atomization mechanism of H2O2 solution was analyzed by calculating dimensionless parameters of Re, We, and Oh numbers with the combination of the operation conditions and physical properties for in-depth understanding the breakup behaviors. The calculation showed that the minimum average diameter of breakup droplets was obtained at 8 wt. % concentration at the investigated range of H2O2 concentration, which kept in agreement with the experimental results.

• Crystal-membrane interactions induced by the scaling of CaSO 4 in MD were studied. • Both experimental and theoretical approaches were employed to address the concerns. • Maximum achievable crystallization pressure was related to the concentration rate. • Competition between the concentration and crystallization effects was analyzed. • Effect of crystalline growth on the crystal-membrane interactions was highlighted. Scaling of calcium sulfate (CaSO 4) is a stumbling block to the development of membrane distillation (MD), which holds promise for the treatment of saline water/wastewater. Despite increasing efforts made to understand the scaling behavior of CaSO 4 in a process of MD and thereby develop strategies for mitigating the negative effects, considerable uncertainty remains about occurrence of the wetting and structural damage that could result from the strong crystal-membrane interactions. This study combined experimental and theoretical approaches to corroborate that a higher degree of supersaturation could be achieved by concentrating the CaSO 4 in the feed at a faster rate; the elevated supersaturation would be in favor of exerting substantially high crystallization pressure on the membrane structures. In particular, the theoretical analysis established two dimensionless groups for measuring the relative importance of the concentration effect and quantifying the essential role played by the crystalline growth, respectively. In addition to alleviating the uncertainty, this study would be beneficial to the design of MD processes with improved scaling resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

Thermo-osmosis refers to fluid migration due to the temperature gradient. The mechanistic understanding of thermo-osmosis in charged nano-porous media is still incomplete, while it is important for several environmental and energy applications, such as low-grade waste heat recovery, wastewater recovery, fuel cells, and nuclear waste storage. This paper presents results from a series of molecular dynamics simulations of thermo-osmosis in charged silica nanochannels that advance the understanding of the phenomenon. Simulations with pure water and water with dissolved NaCl are considered. First, the effect of surface charge on the sign and magnitude of the thermo-osmotic coefficient is quantified. This effect was found to be mainly linked to the structural modifications of an aqueous electrical double layer (EDL) caused by the nanoconfinement and surface charges. In addition, the results illustrate that the surface charges reduce the self-diffusivity and thermo-osmosis of interfacial liquid. The thermo-osmosis was found to change direction when the surface charge density exceeds -0.03C · m -2 . It was found that the thermo-osmotic flow and self-diffusivity increase with the concentration of NaCl. The fluxes of solvent and solute are decoupled by considering the Ludwig-Soret effect of NaCl ions to identify the main mechanisms controlling the behavior. In addition to the advance in microscopic quantification and mechanistic understanding of thermo-osmosis, the work provides approaches to investigate a broader category of coupled heat and mass transfer problems in nanoscale space.

[Display omitted] • Kinetic hydrate inhibitor has a 'concentration effect' on hydrate formation and inhibition. • Kinetic hydrate inhibitor was almost ineffective at an intermediate concentration range. • 'Weakened adsorption' and 'competition' mechanism hypothesis was proposed for explaination. • The universality of the concentration effect was explored at various experimental conditions. Kinetic hydrate inhibitor (KHI) is an eco-friendly and promising technology for hydrate blockage issue in natural gas pipelines, but it remains unclear of how KHI performance would vary at different subcooling and concentration. In this study, the influence of KHI on the kinetics of methane - propane hydrate formation was evaluated with a wide range of subcooling (5–20 ℃) and concentration (100–51000 ppm) conditions, by characterizing the pressure evolution, average hydrate growth rate and hydrate volume fraction. The results put forward a 'concentration effect' concept that represented the nonmonotonic relationship between the performance and concentration of KHI, where KHI obtained higher inhibition performance with either relatively low or high concentration, but became almost ineffective at the intermediate concentration zone. Two hypotheses were then proposed to reveal its internal mechanisms, including the 'weakened adsorption' hypothesis and the 'competition' hypothesis. Results further demonstrated that the above concentration effect became less obvious when the experimental conditions were more contributory for fast hydrate formation, such as the enhanced subcooling and stirring speed. In addition, the universality of concentration effect was preliminarily verified, which was not restricted by the type of KHI or the selected experimental system. To the best of our knowledge, such concentration effect was for the first time systematically investigated and reported in this study, which highlighted the possibility of flexibly selecting the appropriate KHI concentration based on the practical driving force for hydrate formation. [ABSTRACT FROM AUTHOR]

Road verges can facilitate the movement of pollinators and pollen in intensively managed agroecosystems, reducing the negative impacts of fragmentation (i.e., isolation of wild pollinator communities) and enhancing the pollination service provided to wild plants. To assess the role of road verges in sustaining the pollination service to wild plants, we studied gardens consisting of two plant species arranged within sixteen road verges and their adjacent fields during two consecutive seasons in the Argentine Pampas. We assessed the influence of attributes of road verges on pollination service at different scales: road verges width, species richness of flowering plant, and flower abundance (patch scale), crops and successional pastures (adjacent land use scale), and landscape heterogeneity (landscape scale). We measured the pollination service provided to two species of potted plants (Hirschfeldia incana and Lobularia maritima) in three different ways: visitation rate, conspecific and heterospecific pollen transfer to stigmas, and distance of pollen transfer from a fixed source. The number of conspecific and heterospecific pollen grains deposited on stigmas decreased with an increased abundance of floral units in associated road verges, which is caused by a dilution effect on individual plant pollination. Also, the pollen transfer into adjacent fields decreased with an increased abundance of floral units in the nearby road verges, which is caused by a decrease of pollen spillover into adjacent crop fields. The visitation rate within adjacent fields increased with higher flowering plant species richness in associated road verges. Also, the number of conspecific pollen grains in the road verges adjacent to successional pastures increased with higher flowering plant species richness in road verges, which results in a concentration effect of pollinator visits and pollen transfer into road verges. We conclude that managing flower abundance and increasing flowering plant species richness in road verges are crucial practices for maintaining the pollination service of entomophilous plants in intensively managed agroecosystems. • We assessed the role of road verges on insect pollination in rural landscapes. • The number of pollen grains decreased with higher flower abundance. • Pollen transfer into adjacent fields decreased with higher flower abundance. • The visitation rate into adjacent fields increased with higher plant richness. • Distance from the pollen source did not affect the pollen transfer in road verges. [ABSTRACT FROM AUTHOR]

The structural, linear and nonlinear optical properties of PMMA/ZrO 2 and PMMA/WZrO 2 nanocomposites thin films were investigated. Tungstated zirconia nanoparticles were synthesized with different tungsten concentrations (3, 20 and 37% w/w) via solvothermal reflux method. To investigate the effect of weight and doping concentration, thin films with different tungsten ratio (undoped, %3, %20 and %37 W doped) were prepared and also weight percentage of the investigated samples in polymer (10 and 20 wt%) were changed for each doping ratio. The samples were examined using XRD, TEM, XPS and EDX analysis. The linear and nonlinear optical properties were studied by UV–Visible spectrophotometry and Z scan technique. The linear spectra were used to calculate the energy band gap. The fluorescence peak at 375 nm for undoped and doped ZrO 2 nanocomposites are assigned to the presence of oxygen vacancies in the nanostructures. A theoretical model including one photon, two photon and free carrier absorptions and their saturations were used to analyze the experimental data. The linear absorption of all samples increased with increasing weight percentage of the films. The films which have a low tungsten ratio (%3 W) showed minimal absorption. The band gap decreased with addition of tungsten and the increasing nanoparticle weight concentration. OA Z-scan experiment results indicated that the addition of the tungsten to PMMA/ZrO 2 reduced the nonlinear absorption performance. • Transparent thin films of PMMA/ZrO 2 and PMMA/WZrO 2 by spin coating. • Variation of nonlinear absorption coefficients with nanoparticle and doping concentration. • The presence of tungsten reduces nonlinear absorption. • The energy band gap value decreases with the increasing of tungsten ratio. [ABSTRACT FROM AUTHOR]

The development of superconcentrated or water-in-salt electrolytes (WISEs) has paved a new way toward realizing environmentally friendly, nonflammable batteries and supercapacitors based on aqueous electrolytes. The development of new electrolytes, such as WISEs, needs to be accompanied by further studies of the charging mechanism. This is essential to guide the choice of the electrode/electrolyte pairs for optimizing the performance of WISE-based supercapacitors. Therefore, to optimize the performance of carbon/carbon supercapacitors when using new, superconcentrated electrolytes, we present a detailed investigation of the carbon/electrolyte interface by combining electrochemical measurements with Raman and NMR spectroscopy and mass spectrometry. In particular, NMR provides crucial information about the local environment of electrolyte ions inside the carbon pores of the electrode. The results show that the structure of the electrolyte strongly depends on the concentration of the electrolyte and affects the mechanism of charge storage at the positive and negative electrodes.

Molten carbonate electrolysis cells have recently gained interest for the sustainable production of H 2 or syngas to substitute fossil fuels. However, they can be also used for CO 2 sequestration, as they pump it from one electrode inlet to the opposite electrode outlet. Thus, they can easily be applied to segregation of CO 2 from H 2 based fuels while also increasing the fuel heat of combustion for example after a steam reforming reactor. To explore the use of molten carbonate electrolysis cell for this application, in this work the authors investigate the performance of the cell under different operating conditions in term of both operating temperature and fuel electrode gas composition. Polarization curves, gas crossover and electrochemical impedance spectroscopy are used to evaluate specific issues (high electrolyte losses due to water and temperature) or benefits (excess of H 2 O in regard to CO 2 that allows for higher CO 2 capture rate). After, a series of long-term tests at −150 mA cm−2 and 650 °C are performed to demonstrate long term stability. In particular, before electrolyte loss made the performance unstable, different cells are operated for about 1000 h with an average voltage of about 1.14 V demonstrating also the repeatability of such tests. [Display omitted] • Molten carbonate electrolysis cells can be used for CO 2 capture and H 2 upgrading. • Different molten carbonate electrolysis cells were operated for performance study. • Long-term operations (1000 h) were successfully achieved with repeatability. [ABSTRACT FROM AUTHOR]

ZnGa 2 O 4 (ZGO) persistent luminescence (PersL) ceramics doped with different concentrations of Cr3+ were prepared by the co-precipitation method and hot isostatic pressing (HIP) post-treatment. After HIP post-treatment, the ZGO PersL ceramics was significantly improved from opaque to transparent visual appearance due to the elimination of micro-pores during HIP process. The effects of Cr3+ concentration on the morphology, transmittance and PersL properties of ZGO PersL ceramics were systematically investigated. The ZGO PersL ceramics with higher Cr3+ dopant concentrations show less micro-pores and higher transmittance, which indicates that the Cr3+ can also work as a sintering additive to increase the density and to improve the optical quality of ZGO PersL ceramics. The photoluminescence excitation (PLE) and emission (PL) intensities increase with the increase of Cr3+ concentration up to 0.25 at.%. At yet higher Cr3+ concentrations, the ZGO PersL ceramics exhibits weaker PL and PLE intensities which is probably caused by the concentration quenching effect. However, the PersL decay curves show that the PersL performance of ZGO ceramics increases with increasing Cr3+ concentrations, indicating that the doping by Cr3+ ions may cause another traps formation leading to stronger and longer PersL. The PersL decay curves of all ZGO PersL ceramics were fitted by the second-order exponential function, indicating that at least two kinds of traps with different electron release rates exist in the ZGO ceramics. The influence of Cr3+ concentration on the thermoluminescence (TL) of ZGO PersL ceramics was also studied, and the results showed that the TL curves of the pre-sintered ceramics shifted to lower temperatures, indicating that the depth of trap related to Cr3+ ions is shallower than the depth of trap caused by the intrinsic defects. • Cr3+:ZnGa 2 O 4 ceramics were prepared by co-precipitation and HIP post-treatment. • Cr3+ can work as a sintering aid to improve the optical quality of ZGO ceramics. • Concentration quenching occurs when Cr3+ concentration is more than 0.25 at-%. • Oxygen vacancy can lead to the formation of deeper trap. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbamazepine, diclofenac & ibuprofen degradation by TiO 2 photospheres was studied. • Matrix and cocktail effects had negative impact on CBZ, DCF & IBU removal. • Initial low concentrations (µg/L) were easier to treat than higher ones (mg/L). • Transposition to a larger scale solar photoreactor showed better removals. • Same rank order of molecule degradation between the two photoreactors was found. The conditions of wastewater treatment by photo-oxidation are addressed in this work with the aim of highlighting the importance of the matrix, concentration and cocktail effects of pharmaceutical pollutants very present in wastewater treatment plant. The idea is to operate under real conditions, i.e. effluent from the WWTP, representative concentrations and natural irradiation. Photospheres are micrometric glass spheres coated with TiO 2 which have the particularity to float and therefore be much easier to separate from treated water during photocatalysis. Three pharmaceutical target molecules were chosen: carbamazepine (CBZ), diclofenac (DCF) and ibuprofen (IBU) to evaluate, in a controlled 2 L artificial UV photoreactor, the individual and coupled effects of three strategic points: i) the matrix effect (tap water vs filtered treated wastewater), ii) the cocktail effect (one molecule vs the three mixed together) and iii) the initial concentration level effect (µg/L vs mg/L). A 300 L solar photoreactor was also designed for this study to evaluate the transferability of performances. Experiments conducted under controlled conditions highlighted that i) the molecule removal was most negatively impacted by the matrix effect, ii) the cocktail effect, even if still negative, appeared to decrease the difference between the degradation rates and iii) initial low concentrations were easier to degrade than higher laboratory concentrations. Transposition to the larger scale solar photoreactor confirmed the order of molecule degradation: DCF > IBU > DCF when alone and DCF > CBZ > IBU when mixed together but also showed that this set up was actually more efficient in the degradation of these molecules than the artificial photoreactor. [ABSTRACT FROM AUTHOR]