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AbstractBased on fractal theory, the geometric size, surface morphology, and spatial structure of flocs in the hydrophobic flocculation process of coal particles were examined via particle size distribution detection, image analysis technology, and numerical simulation. The floc size distribution curve was classified and discussed via the dual-domain fractal rule, and the variation law of the composition and distribution of the coarse- and fine-grained coal particle flocs with the flocculation process was clarified. The various levels and characteristics of the floc growth geometry were explained by the analysis of the fractal dimension of the individual floc surface and the multiple spectra of the floc groups in the metallographic microscopy image. The hydrophobic flocculation process of coal particles was simulated via the diffusion-limited cluster aggregation model. The gyration fractal dimension was used to examine floc fragmentation and reconstruction and clarify the growth law of the floc spatial structure during the hydrophobic flocculation process. [ABSTRACT FROM AUTHOR]

The spatial and size distributions of titanium diisopropoxide bisacetylacetonate [(C5H7O2)2[(CH3)2CHO]2, also known as Ti(acac)2(OiPr)2] mist, diluted in CH3OH, are investigated in a tubular furnace using atmospheric‐pressure mist chemical vapor deposition (mist CVD). The focus is on the deposition of amorphous (a)‐TiO2 films with tubular furnace temperature and mesh bias as variables. When the furnace temperature reaches 350 °C, the number density of mist particles increases without significant changes in their size distribution, leading to a higher film deposition rate. Further, the deposition rate and average size of the mist particles with lower adhesion coefficient decrease with increasing spatial distance from the furnace inlet. Furthermore, applying a mesh bias results in an increase in the maximum number density of mist particles with a narrower size distribution; however, the overall film deposition rate decreases. These variations are attributed to the chemical reactivity of the mist precursors produced by pyrolysis and mesh bias. The fine mist precursors, which are strongly charged, coordinate with CH3OH and CHO groups through solvation, enhancing their chemical stability and lifetime. This process yields a dense and rigid a‐TiO2 network, improving the junction properties at the a‐TiO2/c‐Si interface. [ABSTRACT FROM AUTHOR]

Introduction: Bivalve aquaculture has direct and indirect effects on plankton communities, which are highly sensitive to short-term (seasonal, interannual) and long-term climate changes, although how these dynamics alter aquaculture ecosystem interactions is poorly understood. Methods: We investigate seasonal patterns in plankton abundance and community structure spanning several size fractions from 0.2 µm up to 5 mm, in a deep aquaculture embayment in northeast Newfoundland, Canada. Results: Using flow cytometry and FlowCam imaging, we observed a clear seasonal relationship between fraction sizes driven by water column stratification (freshwater input, nutrient availability, light availability, water temperature). Plankton abundance decreased proportionally with increasing size fraction, aligning with size spectra theory. Within the bay, greater mesozooplankton abundance, and a greater relative abundance of copepods, was observed closest to the aquaculture lease. No significant spatial effect was observed for phytoplankton composition. Discussion: While the months of August to October showed statistically similar plankton composition and size distribution slopes (i.e., food chain efficiency) and could be used for interannual variability comparisons of plankton composition, sampling for longer periods could capture long-term phenological shifts in plankton abundance and composition. Conclusions provide guidance on optimal sampling to monitor and assess aquaculture pathways of effects. [ABSTRACT FROM AUTHOR]

Acting as substrates for heterogeneous nucleation, native oxides in Al–Mg alloys have shown their potential for grain refinement. However, the limited knowledge about the nature of the oxides in Al–Mg alloys impedes the widespread application as native grain refiners. The aim of this work is to comprehensively investigate the native oxides in Al–Mg alloys through electron microscopy. Our results show that the predominant inclusions in Al–Mg alloys are oxides in three types of oxide films at the micrometer scales: young films, old films and oxide skins. All oxide films consist of discrete oxide particles of three types in nanometer scale depending on the Mg contents: γAl2O3 (< 0.4 wt.%), MgAl2O4 (0.08–3.5 wt.%) and MgO (> 2 wt.%). Specifically, MgAl2O4 particles have sizes ranging from a few tens to a few hundreds nanometer and possess an elementary shape of octahedron faceted by {111} planes. In Al–Mg alloys, the native oxides have a lognormal size distribution, with the average mean size fluctuating in accordance with the oxide configurations as Mg content varies. The agglomerating feature causes inhomogeneous sampling, and dual-peak lognormal curves are found for low-Mg-content alloys (0.08/0.4%), which could be eliminated by increasing the Mg content (2.0/3.5%) or by using the high-shear melt conditioning (HSMC) technology. Understanding the native oxides in Al–Mg alloys shall provide instructions on their application in grain refinement. [ABSTRACT FROM AUTHOR]

We study the role of the size distribution of the banking sector for bailout policy and financial fragility in a model of financial intermediation with limited commitment and noisy sunspots. In particular, due to the different costs of mitigating depositors' losses, differences in financial fragility arise endogenously in the sense that the large banking market admits a higher degree of instability. Moreover, the desire to reduce differences in the amount of bailout funding across segments of the banking system leads the fiscal authority to collect less taxes ex‐ante but ends up rendering the scope for run equilibria larger. [ABSTRACT FROM AUTHOR]

To investigate the reproductive behavior of the frigate tuna (Auxis thazard) along the North Atlantic coast of Morocco, a comprehensive study was conducted between February and October 2020. A total of 215 frigate tuna specimens, obtained from both artisanal fishery and commercial purseseiners, were meticulously examined on a monthly basis. The study focused on evaluating various reproductive parameters including sex ratio, condition factor (K), gonadosomatic index (GSI), and sexual maturity progression. The findings of this study revealed that the straight fork lengths of the frigate tuna ranged from 30 to 43cm. Analysis of the sex ratio indicated a slight dominance of females, with a ratio of 1.06 females to every male (observed sex ratio: 1:0.06; X² observed = 1.21, which was below the theoretical X² = 3.84 threshold at P< 0.05). The size at which individuals reached sexual maturity (FL 50) was estimated to be 36cm for females and 38cm for males. Through monthly assessments, it was observed that the variation in maturity stages, GSI, and K values suggested a spawning period predominantly occurring between June and August, with a peak in July. This temporal pattern underscores the importance of understanding the reproductive dynamics of the frigate tuna populations in this region. [ABSTRACT FROM AUTHOR]

Religious burning (RB) has been identified as a major source of atmospheric aerosols on the Qinghai‐Tibet Plateau. However, there is limited understanding of the detailed chemical composition, size distribution, and optical properties of RB aerosols in this region. To characterize these important aerosol properties, ambient PM2.5 and size resolved aerosols from RB emissions in Lhasa were collected during summer 2019. Organic functional group (OFG) and inorganic ion composition was measured using Fourier transform infrared spectroscopy and ion chromatography, respectively. The ambient PM2.5 was dominated by organic components, with the OFG concentrations significantly higher during religious events, reflecting the substantial impact of RB emissions on local air quality. The RB aerosols were characterized by high fractions of alkane (34%), hydroxyl (29%), and carboxylic acid (13%) groups, with peak mass in the accumulation mode (0.56–1.00 μm). The high abundance of hydroxyl group and the size distribution pattern suggested that the RB aerosols were formed from volatilization of fuel materials followed by unaltered condensation, a process that may be unique to the low‐temperature, low‐oxygen burning in the scattered burners at the temples. The absorption coefficient of RB aerosols showed similar size distribution to the mass size distribution, but the absorption Ångström exponent displayed the lowest value in the 0.56–1.00 μm size mode. This specific size distribution aligned with the mass fraction of carboxylic acids and mirrored the mass proportion of alkanes, suggesting that smaller and larger particles were enriched with substances that have higher light‐absorbing capabilities. Plain Language Summary: Religious burning (RB) has been found to be a major source of air pollution particles on the Qinghai‐Tibet Plateau. However, much remains to be learned about the chemical composition, size distribution, and light‐absorbing properties of these particles. To better understand these properties, we collected particles from ambient air and the RB emissions in Lhasa during the summer of 2019 and measured the organic and inorganic components of the particles. RB particles were made of high amounts of alkane (34%) and hydroxyl (29%) groups, which had a big impact on local air quality. The high amount of hydroxyl group and the size pattern suggest that the RB particles were formed when fuel materials evaporate and then condense, which may be unique to the low‐temperature, low‐oxygen burning in the scattered burners at the temples. The light‐absorbing properties of the RB particles showed a similar size pattern to the mass size distribution, but the smallest and largest particles had higher light‐absorbing abilities. This specific size distribution matches the percentage of carboxylic acids and is the opposite of the amount of alkanes, suggesting that smaller and larger particles were enriched with substances that can absorb more light. Key Points: Lhasa PM2.5 is primarily composed of hydroxyl, alkane, and carboxylic acid groups, heavily influenced by religious burning (RB) activitiesFresh RB aerosols are likely formed via volatilization and condensation processes during the low‐temperature and low‐oxygen burningThe Ångström exponent of water‐soluble organic carbon in RB aerosols shows an opposite size distribution to the mass and absorption coefficient of the aerosols [ABSTRACT FROM AUTHOR]

Brown carbon (BrC) is one of the important light absorption substances that have high light absorption ability under short wavelength light. However, limit studies have focused on the BrC emission from ships. In this study, size-segregated particulate matters (PM) were collected from three different types of ships, light absorption characteristics and size distribution of methanol-soluble BrC and water-soluble BrC in PM from ship exhausts were investigated. Results showed that four-stroke low-power diesel fishing boat (4-LDF) had the highest mass concentrations of methanol-soluble organic carbon (MSOC) and water-soluble organic carbon (WSOC), followed by 2-stroke high-power heavy-fuel-oil vessel (2-HHV), and four-stroke high-power marine-diesel vessel (4-HMV). While 2-HHV had obviously higher light absorption coefficients of methanol-soluble BrC (Abs 365,M) and water-soluble BrC (Abs 365,W) in unit weight of PM than the other two types of ships. The tested ships presented comparable or higher absorption efficiency of BrC in water extracts (MAE 365,W) compared with other BrC emission sources. Majority of BrC was concentrated in fine particles, and the particle size distributions of both Abs 365,M and Abs 365,W showed bimodal patterns, peaking at 0.43–0.65 µm and 4.7–5.8 µm, respectively. However, different particle size distributions were found for MAE 365,M between diesel and heavy fuel oil ships. Besides, different wavelength dependence in particles with different size were also detected. Ship exhaust could be confirmed as a non-ignorable BrC emission source, and complex influencing factor could affect the light absorption characteristics of ship emissions. Particle size should also be considered when light absorption ability of BrC was evaluated. [ABSTRACT FROM AUTHOR]

Human pluripotent stem cells (hPSCs) hold promise for regenerative medicine to replace essential cells that die or become dysfunctional. In some cases, these cells can be used to form clusters whose size distribution affects the growth dynamics. We develop models to predict cluster size distributions of hPSCs based on several plausible hypotheses, including (0) exponential growth, (1) surface growth, (2) Logistic growth, and (3) Gompertz growth. We use experimental data to investigate these models. A partial differential equation for the dynamics of the cluster size distribution is used to fit parameters (rates of growth, mortality, etc.). A comparison of the models using their mean squared error and the Akaike Information criterion suggests that Models 1 (surface growth) or 2 (Logistic growth) best describe the data. [ABSTRACT FROM AUTHOR]

Mesh filters are frequently employed in water-saving irrigation fields. Studies addressing the method of cake formation and the characteristics of the cake during the mesh filter's growing phase are still missing. One-way and orthogonal experiments were carried out using mesh filters with 220 μm and 320 μm aperture sizes as the research objects, taking particle concentrations, inlet flow, and growth phases as experimental factors. According to the variation rule of seed pressure drop in the formation process of filter cake, the growth process of filter cake is divided into four stages, which are as follows: slow blockage first and second stages (M1, M2), fast blockage stage (M3), and filter cake filtration stage (M4). Moreover, the size distribution, porosity (ε), pore-to-particle ratio (KP), and median size (d50) of the filter cake were used to represent the structural characteristics. The results show that the growth of filter cake was a process that started with the filling of mesh pores by intercepted particles and progressed to the filling of large-particle skeleton pores by subsequently filtered particles. During this process, the proportion of intercepted particles gradually decreased, while the proportion of filtered particles increased incrementally, and the median size (d50) and porosity (ε) decreased. Meanwhile, the smaller the aperture size of the screen, the smaller the filter cake's median size (d50) was, but the larger the pore-to-particle ratio (KP) was. As the flow rate increased, the porosity (ε) was augmented in the M1 and M2 stages; however, it decreased in the M3 and M4 stages. The concentration had a minor influence on the filter cake's porosity. Lastly, the regression model for filter cake porosity under two aperture size conditions was established, based on factors such as flow rate, concentration, and growth stage. The coefficients of determination, R2, for the model were 90.33% and 80.73%, indicating a good fit. [ABSTRACT FROM AUTHOR]

Horses stay in different types of stables; especially during the cold season, they stay inside for most of the day. A stable is also a place where many people spend quite a lot of time either as employees who care for and train horses or as equine enthusiasts. Keeping horses in stables causes their constant exposure to high concentrations of particulate matter (PM) and molds in the air inside these facilities. The study was conducted in Udórz Stud Farm located in the southern region of Poland. It was carried out in two different types of stables: three runners and two box stables. The study continued for 2 years; samples were collected in each season of the year. The following devices were used: a six-stage Andersen-Graseby cascade impactor, the DustTrak™ II Aerosol Monitor 8530. The obtained results allowed for the conclusion that horses kept in box stables are exposed to lower concentrations of molds and yeasts than those kept in runners. Molds dominated in the stable air during humid periods—spring and autumn—while yeasts were more prominent during summer and winter. It was observed that cleaning stables reduces the morphotic elements of fungi in the air, even though it results in a higher level of particulate matter in the stable air. It should be noted that microclimate conditions were optimal for horses practically throughout the whole year. Key points: • In stables, there is a high level of air intoxication, both by yeast and by mold fungi • The concentrations of fungi in the air depend on the season and the stable cleaning procedure • The PM concentrations depend on the type of stable [ABSTRACT FROM AUTHOR]

This study, conducted in Debrecen, Hungary, aimed to analyse atmospheric particulate matter (APM or PM) through radiocarbon and PIXE analyses during the winter smog (23–25 January) and spring (15–18 May) seasons. The information presented in this pilot study aims to provide insight into the importance of utilising detailed characteristics of the mass size distributions of fossil carbon (ff) and contemporary carbon (fC) content. Additionally, it seeks to compare these characteristics with the size distributions of various elements to enable even more accurate PM source identification. In winter, APM concentrations were 86.27 μg/m3 (total), 17.07 μg/m3 (fC) and 10.4 μg/m3 (ff). In spring, these values changed to 29.5 μg/m3, 2.64 μg/m3 and 7.01 μg/m3, respectively. Notably, differences in mass size distribution patterns were observed between the two seasons, suggesting varied sources for contemporary carbon. Biomass burning emerged as a crucial source during the smog period, supported by similar MMAD (Mass Median Aerodynamic Diameter) values and a strong correlation (r = 0.95, p < 0.01) between potassium and fC. In spring, a significant change in the concentration and distribution of fC occurred, with a broad, coarse mode and a less prominent accumulation mode. Ff was found to have similar distributions as PM, with nearly the same MMADs, during both periods. Finally, a comprehensive comparison of modal characteristics identified specific sources for the various components, including biomass burning, vehicle exhaust, coal and oil combustion, vehicle non-exhaust, road dust, tyre abrasion, mineral dust and biogenic emission. This study showcases how using radiocarbon and PIXE analysis in size distribution data can enhance our understanding of the sources of PM and their effects on different size fractions of PM. [ABSTRACT FROM AUTHOR]

• Size-resolved Effective density of submicron atmospheric particles in Shenzhen were measured online using DMA-CPMA-CPC combined system. • Bimodal distribution feature of particle effective density was identified, including a main density mode and a sub density mode, by bimodal Gaussian fitting. • Particle effective density exhibited a high occurrence frequency of bimodal distribution, and two density modes exhibited opposite size distribution trends. • Effective density variation was highly correlated with the proportion of OA, sulfates and BC. Effective density (ρ eff) is one of the most important physical properties of atmospheric particles, providing important references in exploring the emissions and aging processes of fresh particles. In this study, a combined system of differential mobility analyzer, centrifugal particle mass analyzer, and condensation particle counter was used to periodically measure the ρ eff of atmospheric particles in Shenzhen from Oct. 2021 to Jan. 2022. Results showed that the ρ eff of particles with various size presented a bimodal distribution, which could be divided into main density (ρ m , main peak, corresponding to relatively dense particles after aging) and sub density (ρ s , sub peak, corresponding to fresh particles). The occurrence frequencies of ρ s of particles with diameters of 50 and 80 nm were less than 20%, but were as high as about 40% of that with diameters from 120 to 350 nm. The ρ m showed increasing trend with the size of particles, while ρ s decreased as the increasing of the size of particles. The ρ eff on pollution day varied significantly with chemical compositions. The increasing of the proportion of sulfate could promote the increasing of ρ eff , while black carbon and organic matter caused opposite effects, which may be related to various factors, including the difference of the material density and morphology of various chemical components. The ρ eff of 50, 80 and 120 nm particles decreased considerably during the new particle formation event, indicating that organic condensation was an important contributor to new particle growth. [ABSTRACT FROM AUTHOR]

Bulk microphysics schemes continue to face challenges due in part to the necessary simplification of hydrometeor properties and processes that is inherent to any parameterization. In all operational bulk schemes, one such simplification is the division of liquid water into two subcategories (cloud and rain) when predicting the evolution of warm clouds. It was previously found that biases in collisional growth in a bulk scheme with these separate liquid water categories can be mitigated with a unified liquid water category in which cloud and rain are contained within the same category. In this study, we examine the effect of artificially separating the liquid water category on other microphysical processes and in more realistic settings. Both our idealized 1D and 3D results show that a unified category bulk scheme is fundamentally better at predicting the timing and intensity of rain from warm‐phase cumulus clouds compared to a traditional (separate) category bulk scheme. This is because a unified category bulk scheme allows a bimodal distribution to exist within one traditional "rain" category, whereas separate category bulk scheme only have one mode per category. This advantage allows the unified bulk scheme to retain the information of the largest droplets even as they fall through a layer of small raindrops. A separate category bulk scheme fails to represent this bimodal feature in comparison. Plain Language Summary: Bulk microphysics schemes are fast enough for simulating the evolution of clouds in weather and climate prediction, but they also face problems when calculating the collision and falling of water droplets. Some of the problems might not come from our lack of cloud physics knowledge but how the schemes are designed. For example, bulk schemes artificially divide the liquid water category into smaller droplets ("cloud") and larger droplets ("rain"). It was found that the biases typically produced by a separate category bulk scheme can be fixed with a unified category bulk scheme. In this study, we look into how a unified category bulk scheme compares to a separate category one under more physical processes and model settings. We find that a unified category bulk scheme consistently outperforms a separate category one, especially when predicting the timing and heaviness of rainfall. This is because collision and falling of water droplets can create droplet size distributions with two peaks in the traditional cloud or rain category, which cannot be modeled with a separate category bulk scheme. Key Points: A unified category bulk scheme accurately predicts rainfall timing and intensity far better than a traditional separate category schemeSedimentation of bimodal rain distributions is poorly captured by a separate category scheme but well captured by a unified category oneThe improvement arises from more flexibility in size distributions despite the same number of total predicted moments in both schemes [ABSTRACT FROM AUTHOR]

Long-term exposure to a relatively high concentration of airborne bacteria emitted from intensive livestock houses could potentially threaten the health and welfare of animals and workers. There is a dual effect of air sterilization and promotion of vitamin D synthesis for the specific bands of ultraviolet light. This study investigated the potential use of A-band ultraviolet (UVA) tubes as a clean and safe way of reducing airborne bacteria and improving calf health. The composition and emission characteristics of airborne bacteria were investigated and used to determine the correct operating regime of UVA tubes in calf houses. Intermittent exceedances of indoor airborne bacteria were observed in closed calf houses. The measured emission intensity of airborne bacteria was 1.13 ± 0.09 × 107 CFU h−1 per calf. Proteobacteria were the dominant microbial species in the air inside and outside calf houses. After UVA radiation, the indoor culturable airborne bacteria decreased in all particle size ranges of the Anderson sampler, and it showed the highest reduction rate in the size range of 3.3–4.7 μm. The results of this study would enrich the knowledge of the source characteristics of the airborne bacteria in intensive livestock farming and contribute to the environmental control of cattle in intensive livestock production. [ABSTRACT FROM AUTHOR]

Plastic fragmentation alters the size distribution of plastic waste in aquatic habitats, which is accelerated by mechanical stress and weathering degradation processes. Microplastic pieces constitute the vast bulk of plastic pollution in terms of quantity. Their size distribution has been shown to follow a power-law for larger fragments. This work introduces a novel model inspired by raindrop formation, incorporating local oceanographic processes and fragment size, aiming to improve the understanding and prediction of plastic fragmentation in marine environments. Particles can fragment when they reach a certain size, or when shear forces become too strong. Plastic aging's effect on size distribution is also investigated. [ABSTRACT FROM AUTHOR]

Dust emission fluxes during wind soil erosion are usually estimated using a dust concentration vertical gradient, by assuming a constant dust flux layer between the surface and the dust measurement levels. Here, we investigate the existence of this layer during erosion events recorded in Iceland and Jordan. Size‐resolved dust fluxes were estimated at three levels between 2 and 4 m using the eddy‐covariance method. Dust fluxes were found mainly constant only between the two upper levels in Iceland, the lower dust flux being often stronger and richer in coarse particles, while dust fluxes in Jordan were nearly constant across all levels. The wind dynamics could not explain the absence of a constant dust flux layer in Iceland. We show that the presence of stationary dust source patches in Iceland, related to surface humidity, created a non‐uniform dust layer near the surface, named dust roughness sublayer (DRSL), where individual plumes behind each patch interact but do not fully mix. The lowest dust measurement level was probably located within this sublayer while the upper ones were located above, such that there the emitted dust became spatially well‐mixed. This explains near the surface in Iceland, the more intermittent dust concentration, its low correlation with the dust concentrations above, and the richer dust flux in coarse particles due to their lower deposition contribution. Our findings highlight the importance of estimating dust fluxes above a dust blending height whose characteristics depend on the dust source patchiness caused by surface humidity or the presence of sparse non‐erosive elements. Plain Language Summary: During soil erosion by wind, dust flux from the surface is estimated at a few meters height, by assuming the existence of a constant dust flux layer between the surface and the dust measurement levels. Here, we investigated for the first time the existence of this layer during erosion events in Iceland and Jordan, by estimating the dust fluxes at three levels between 2 and 4 m height. In Iceland, the dust fluxes were constant only between the two upper levels. In Jordan, the dust fluxes remained constant across all levels. We demonstrates that the absence of a constant dust flux layer in Iceland is due to patches of stationary dust sources, which are related to surface humidity. These patches created a non‐uniform dust layer near the surface, known as the dust roughness sublayer. In this layer, individual plumes behind each patch interact but do not fully mix. The lowest dust measurement level was likely within this sublayer, while the upper measurements were located above it. Our findings highlight the importance of estimating dust fluxes above a dust blending height, which depends on the patchiness of the dust source caused by surface humidity or the presence of sparse non‐erosive elements. Key Points: Size‐resolved dust emission fluxes have been estimated for the first time at different heights during erosion events in Iceland and JordanUnlike in Jordan, the absence of a constant dust flux layer in Iceland is due to the dust source patchiness related to surface humidityOur results highlight the importance of estimating dust fluxes above a dust blending height that depends on the dust source patchiness [ABSTRACT FROM AUTHOR]

A brake dynamometer has been modified to accurately study the concentration and size distribution of wear particles in different testing conditions. The test equipment was a charged low-pressure impactor ELPI+ from Dekati, Finland. 29 test conditions were defined based on speed, acceleration and initial brake temperature. Additionally, five different types of brake pads were selected for testing to provide a more comprehensive understanding of the particle size distribution characteristics of brake wear particles. The results showed that the mass of BWPs was unimodal in the range of 0.01-8.11 µm, with peak sizes at 2-5 µm or >8.11 µm, and particles of 0.5-3.0 µm accounted for an average of 49.09% of the total particulate mass, while particles with sizes of 3.0-8.11 µm accounted for an average of 49.72% of the total particulate mass. The number of particles emitted by abrasion had a bimodal distribution, with one in the nucleation mode and the other in the accumulation mode, with peak sizes of <10 nm and 1 µm, respectively; the nucleation mode particles accounted for an average of 60.11% of the total PN10, and the ultrafine particles accounted for an average of 82.15%. [ABSTRACT FROM AUTHOR]

The sizes, shapes, and combination configurations of thermally conductive fillers critically influence the heat dissipation performance of their polymer composites. Herein, we combined ball-milling and homogenizing together to exfoliate hexagonal boron nitride (h-BN) by using hydroxyethyl cellulose (HEC) aqueous solution as medium, and then assembled the exfoliated boron nitride nanosheets (BNNSs) with aramid nanofibers (ANFs) to construct composite films, of which the mechanical properties and thermal conductivities were thoroughly investigated. The HEC solution with suitable viscosity could produce large size BNNSs due to the strong resistance to impacting forces during ball-milling, but overhigh viscosity would lower the lateral sizes and generate some nanoparticles (NPs) due to the poor dispersity of h-BN that may lead to direct contact between h-BN and milling balls. Homogenization further reduced the lateral sizes of BNNSs and produced abundant NPs; HEC protection could inhibit this size reducing trend but result in the in-homogeneous distribution of BNNSs and the formation of more NPs. Compared with the BNNSs alone, the hybrid of BNNSs and NPs yielded higher mechanical strength and thermal conductivity for the composites, possibly because the NPs could reinforce and bridge the BNNSs to form compact microstructure and highway for thermal conduction. Ultimately, we obtained the highest thermal conductivity of 39.25 W·m–1·K–1 for the ANF/BNNS composite films, which have the potential to be used as heat sink materials for the thermal management of electronic devices and batteries. [ABSTRACT FROM AUTHOR]

Objective: Our objective was to use sportfishing tournament data to determine whether sizes of Dolphinfish Coryphaena hippurus have been changing in the western North Atlantic (WNA) over recent decades. Methods: We sampled North Carolina, South Carolina, and Florida marine sportfishing tournament landings for Dolphinfish lengths. Linear models were separately fitted to length data for males and females by regressing length against year. A subset of these models (analysis of covariance) considered tournament as a factor. Result: An analysis of covariance model with a separate regression slope for each tournament provided the best fit to the data for male and female Dolphinfish. Meaningful temporal declines in the length of males and females were found for four of the five tournaments (no changes in length were observed for the fifth tournament). Median total length declines of 168, 105, 103, and 426 mm were predicted for males, and declines of 354, 133, 131, and 246 mm were predicted for females. Declines in the largest observed sizes of Dolphinfish (97.5% confidence limit) were found for most tournament‐ and sex‐specific combinations of data and could suggest excess fishing mortality on the population. Conclusion: Declines in Dolphinfish size in the WNA region could have ramifications for conservation of the population given that these size changes translate into reduced individual fecundity of female Dolphinfish. Causes of the size decline could be fishing effects, environmental effects, or a combination of these. Reductions in individual size may be occurring simultaneously with declines in abundance identified in other recent research using fishery‐dependent data collected in the WNA. Impact statementUsing fishery‐dependent data to study changes in fish size can be difficult because the assumption of constant selectivity is infrequently met. Our study shows the utility of using sportfishing tournament data to track changes in fish size when selectivity can be assumed to remain constant throughout the sampling period. Our results are informative for U.S. federal fishery managers who are considering updates to output controls (e.g., size limits and bag limits) to help conserve the Dolphinfish stock in the western North Atlantic region. [ABSTRACT FROM AUTHOR]

In aquaculture, biological hazards can be exposed to workers in the form of bioaerosols. This study is to evaluate the level of biological hazard exposure and to provide fundamental data for the health management of aquaculture workers in Korea. A field survey was conducted to measure bioaerosol exposure at ten aquaculture farms in areas where Korean aquaculture is concentrated. Airborne bacteria and fungi with size distribution and identification were measured by simultaneously monitoring temperature and relative humidity. Particularly, high concentrations of airborne bacteria and fungi were observed in farms G and H. Compared to the standards set by the Korean Ministry of Environment, both total airborne bacteria and fungi concentrations exceeded the limit in farms G and H, with the airborne fungi concentration showing four times higher than the standard. As a cause, it is believed to be the quantity and form of work. In size distribution, it was similar to previous study. However, the respirable size range accounted for more than 50% of total concentration, so extra caution should be needed. Staphylococcus spp., Micrococcus spp., Corynebacterium spp., and Bacillus spp. are dominant species for airborne bacteria whereas Cladosporium spp., Penicillium spp., Aspergillus spp., and Alternaria spp. are dominant species for airborne fungi. Most farms had concentrations below the standard, but two farms exceeded the standard, likely due to work type. And some caution is needed for respirable size bioaerosol. Further research is needed, considering additional factors such as tank type, fish species, and type of works. [ABSTRACT FROM AUTHOR]

Size distribution of aerosols and carbon fractions can help identify sources and explore formation mechanisms, and lung deposition surface area (LDSA) is an important indicator for health risk assessment of aerosol particles deposited in the alveolar region of the human respiratory tract. From December 2017 to November 2018, the size distribution and LDSA of indoor and outdoor aerosols in Nanchang was investigated by using the electrical low-pressure impactor (ELPI+), and the results showed that the major airborne particles in the regional mixing receptor sites, roadside, printing room, and students' dormitories during the sampling period were the Nucleation and Accumulation modes, the Aitken and Nucleation modes, the Nucleation mode, the Accumulation mode. The size distributions of organic carbon (OC) in outdoor and indoor air particles were similar, with a single peak, and the peak appeared in the 7 th particle size class (0.256~0.382 µm). The size distributions of elemental carbon (EC) in particles showed a single peak indoors, and multiple peaks outdoors. The size distribution of OC/EC ratios of different microenvironmental particles mostly showed a "L" shape, but there is no significant difference in the OC/EC ratio of particles with different particle sizes in the printing room, which is approximately in a "--" shape. The dominant carbon components of outdoor air particulate matter were OC2, OC3, OC4 and EC1, which mainly originated from coal combustion emissions and motor vehicle exhaust, while the dominant carbon components of indoor air particulate matter were OC1, OC2 and OC3, which mainly originated from cigarette combustion and outdoor air infiltration. The LDSA of different microenvironmental particles varied, and the daily mean values of LDSA were 49.0, 10.9, 29.9, and 31.0 µm²/m³ for the outdoor mixed-source receptor sites, the roadside, and the indoor printing room and the students' dormitory, respectively, and the LDSA of the particles was very high in the indoor environments with obvious contributing sources (e.g., printing work or cigarette combustion) for a short period of time, especially under the influence of the cigarette combustion, exceeding the maximum value of ambient air particulate LDSA. High percentage of LDSA was for particles smaller than 100 nm in roadside air, and high percentage of LDSA for particles in the 100~600 nm size range in indoor environments where there is a cigarette combustion source. [ABSTRACT FROM AUTHOR]

Muncar is the largest fish landing which produced Bali Sardinella (Sardinella lemuru) in Banyuwangi. Sardinella was caught by purse seine. During fishing by purse seine, target species was Bali Sardinella while another catch was called bycatch. Some researchers indicated that bycatch was one factor affecting fish stock depletion. The aim of this research was to investigate catch composition and size distribution of dominant fish caught by purse seine. Result of observation at 10 fishing trip indicated that catch of purse seine was dominated by Bali Sardinella (Sardinella lemuru) which total account of 3.360 fishes or 77,83 % as a target catch, and the bycatch is layang (Decapterus ruselli) about 596 fishes or 13,77%, and slengseng (Scomber australasicus) about 363 fishes or 8,40%. The size of lemuru who caught in this research is between 12-21 cm. Dominant caught at size 14-15 cm about 2.032 fishes (46,97%), and a least caught at >18 cm about seven fishes (0,16%). The size of layang who caught in this research is between 13-25 cm. Dominant caught at size 19-20,5 cm about 255 fishes (5,20%), and a least caught at size 23,5-25 cm about one fishes (0,02%). The size of slengseng who caught in this research is between 13-28 cm. Dominant caught at size 23-25 cm about 143 fishes (3,30%) and least caught at size 27-28 cm only two fishes (0,04%). [ABSTRACT FROM AUTHOR]

Purpose: A comparative assessment was performed to evaluate the potential of particle sizing by an ensemble based conventional dynamic light scattering (DLS) technique and an emerging technology based on tunable resistive pulse sensing (TRPS) using particle by particle approach by evaluating three different types of vaccine formulations representing three case studies and showing the limitation of each technique, instrument variability, sensitivity, and the resolution in mixed population. Methods: Three types of in-house vaccine formulations- a protein antigen, an outer membrane vesicle and viral particles were simultaneously evaluated by TRPS based Exoid and two DLS instruments-Zetatrac and Zetasizer for particle size distribution, aggregates, and resolution of polydisperse species. Results: The data from first case study show the risk of possible size overestimation and size averaging in polydisperse samples in DLS measurements which can be addressed by the TRPS analysis. It also shows how TRPS may be utilized only to large size antigens due to its limited size range. The second case study highlights the difference in the sensitivities of two DLS instruments working on the same principle. The third case study show that how TRPS can better resolve the large aggregate species compare to DLS in polydisperse samples. Conclusion: This analysis shows that TRPS can be used as an orthogonal technique in addition to conventional DLS based methods for more precise and in-depth characterization. Both techniques are efficient in size characterization and produce comparable results, however the choice will depend on the type of formulation and size range to be evaluated. [ABSTRACT FROM AUTHOR]

The Lorenz curve is used to describe the relationship between the cumulative proportion of household income and the number of households of an economy. The extent to which the Lorenz curve deviates from the line of equality (i.e., y = x) is quantified by the Gini coefficient. Prior models are based on the simulated and empirical data of income distributions. In biology, the Lorenz curves of cell or organ size distributions tend to have similar shapes. When the Lorenz curve is rotated by 135 degrees counterclockwise and shifted to the right by a distance of 2 , a three-parameter performance equation (PE), and its generalized version with five parameters (GPE), accurately describe this rotated and right-shifted curve. However, in prior studies, PE and GPE were not compared with the other Lorenz equations, and little is known about whether the skewness of the distribution could influence the validity of these equations. To address these two issues, simulation data from the beta distributions with different skewness values and six empirical datasets of plant (organ) size distributions were used to compare PE and GPE with three other Lorenz equations in describing the rotated and right-shifted plant (organ) size distributions. The root-mean-square error and Akaike information criterion were used to assess the validity of the two performance equations and the three other Lorenz equations. PE and GPE were both validated in describing the rotated and right-shifted simulation and empirical data of plant (organ) distributions. Nevertheless, GPE worked better than PE and the three other Lorenz equations from the perspectives of the goodness of fit, and the trade-off between the goodness of fit and the model structural complexity. Analyses indicate that GPE provides a powerful tool for quantifying size distributions across a broad spectrum of organic entities and can be used in a variety of ecological and evolutionary applications. Even for the simulation data from hypothetical extreme skewed distribution curves, GPE still worked well. [ABSTRACT FROM AUTHOR]

The experiment of Al‐deoxidized steel coupling with Mg treatment is conducted under three cooling methods to observe the size and morphology of MgAl2O4. Most of MgAl2O4 in the water‐cooled steel are sphere or ellipsoid‐like shape, in the furnace‐cooled steel are cubic or octahedral‐like shape, and in the air‐cooled steel are irregular shape. The quantity of inclusions in the size of 1–3 μm increases with the increasing cooling rate, whereas the quantity of the other size decreases with the increasing cooling rate. The result shows that the changing of cooling methods has little effect on the critical size and the nucleation rate of MgAl2O4. The growth of MgAl2O4 is effected by diffusion, Ostwald, and collision growth, and the increasing cooling rate leads to the decreasing growth time. The size of MgAl2O4 is decided by the diffusion of Mg and the growth time of MgAl2O4. Four possible morphological transformation paths of MgAl2O4 in steel are found, and the shape of MgAl2O4 can evolve from sphere or ellipsoid to octahedron via truncated octahedron or cubic‐like shape. The final morphology of MgAl2O4 is controlled by the transformation path which has a close relationship with the cooling rate. [ABSTRACT FROM AUTHOR]

During the screening process of fine-grained coal, there is often blockage and detachment of screening plates, a novel screen surface with an additional striking shaft was proposed to solve the problem. The motion characteristics of the striking shaft and screen surface under different excitation parameters were systematically investigated by vibration test and analysis system. The effect of operating parameters on the elastic screening performance was explored through screening experiments. The results showed that the vibrating frequency of the striking shaft was consistent with that of the motor, whose motion waveform was simple harmonic and moved in the straight trajectory. The acceleration and displacement at 1/2 of the screen surface were significantly higher than the values at 1/4, which reached 304.57 m/s2 and 31.87 mm, respectively, and the ejection strength of particles was 18.47 at this time. It was found that when the exciting force was 18 kN, the excitation frequency was 12.0 Hz, and the processing capacity was 14 t/h·m2, the elastic screening could achieve the best screening performance, where the screening efficiency was 83.94%, and the total misplaced content was 8.36%. For the design of elastic screening equipment, this study will provide valuable theoretical and technical guidance. [ABSTRACT FROM AUTHOR]

Horticultural plant material offers several advantages for isolating exosomes and other natural plant-derived exosome-like nanoparticles (PDENs) due to the accessibility and affordability of plant material for widespread applications. This study aims to explore the impacts of the tomato genotype ('Admiro', 'Roma', 'Brooklyn', 'Marmande' and 'Betalux') and the main cultivation parameters in controlled environment agriculture on the yield and properties of their PDENs for pharmaceutical and cosmeceutical applications. The PDEN yield, size distribution, and antioxidative properties of young tomato seedlings were evaluated. The 'Betalux' tomato was distinguished by a remarkably higher nanoparticle concentration and a uniform size distribution and was selected for further experiments. The impact of cultivation temperature (18, 22, and 26 °C), nitrogen nutrition (0, 250, and 500 mg L−1), and the lighting photosynthetic photon flux density (PPFD; 150, 250, and 450 µmol m−2 s−1) on nanoparticle properties was investigated. Optimal conditions consisting of a temperature of 22 °C, 250 mg L−1 nitrogen nutrition, and 250 µmol m−2 s−1 lighting PPFD were used as a reference. Optimal temperature, nitrogen nutrition, and lighting intensity resulted in the highest nanoparticle yield, the most uniform particle distribution, and the highest impact of PDEN preparations on keratinocyte metabolic activity. Deviation from optimal cultivation conditions reduced the tomato biomass and the PDEN protein and yield. [ABSTRACT FROM AUTHOR]

The blue crab Callinectes sapidus Rathbun, 1896 is an invasive species in the Mediterranean, with a remarkable ability to adapt to various habitats, and thereby having significant impacts on biodiversity and artisanal fishing activities. Currently, fishing is a measure being considered to control blue crab populations in invaded sites. However, it is necessary to understand the temporal structure of blue crab populations (e.g., growth, reproduction, sexual maturity) to determine specific periods when control measures need to be implemented. Considering the species' ability to adapt to various habitats, it is crucial to evaluate how temperature and salinity influence population structure. In this study, we present fishers-dependent monitoring on the temporal population structure of blue crabs in two lagoons in Corsica (France) over 12 months. Through this approach, we provide new information that can assist in decision-making for the implementation of control measures. Even though these two lagoons are geographically close, blue crab populations showed differences, particularly in terms of sexual maturity. Specimens from Biguglia mature later (males: 16.16 cm; females: 16.79 cm) than those in the Palo Lagoon (males: 14.38 cm; females: 13.86 cm). Seasonal size distribution also showed differences between the lagoons and within the same lagoon between males and females. Temperature and salinity had a significant effect on the monthly relationship between carapace width and wet weight (referred to here as growth rate) for males and females and between the lagoons. In the Biguglia Lagoon, the higher the temperature, the greater the growth rate over a wide salinity window (16–30 psu); for females, the environmental window was restricted (temperature: 20–30°C; salinities > 16 psu). The dynamics differed in the Palo Lagoon, with a more restricted high growth rate window for males, and females showed a much wider window, with high growth rates over the entire temperature and salinity range. By employing blue crab’s populations monitoring along with environmental parameters, we were able to determine how the environment influenced the blue crab’s population structure, thus identifying periods conducive to species control. The most effective strategy would undoubtedly be to eliminate females before their period of sexual maturity and copulation ensue. In our case, this would involve intensive control in summer for Biguglia and in spring for Palo. These recommendations have been translated into operations to be implemented as part of the ''Territorial Plan for Combating the Blue Crab (Callinectes sapidus) in Corsica (2024–2027)''.

Introduction: The present study analyzed the infiltration behavior of sizefractionated particles and the influencing parameters. Materials and methods: The studies were carried out in two apartments under varying conditions of airtightness, utilizing real-time surveillance of Particulate Matters (PM0.3, PM1.0, PM2.5, PM10), along with air exchange rates and meteorological factors. The seasonal variations of the indoor dissemination of particulate matters have been also discussed. Results: The analysis of correlations indicated a strong dependency of indoor Particulate Matter (PM) concentrations on outdoor levels. However, the penetration patterns varied across different particle sizes. The highest contribution to outdoor PM10 was observed for PM2.5-10 while indoors, the predominant particle size was among the finer categories, PM0.3-1.0. Moreover, window air-tightening appeared to decrease the overall effective leakage area of the building envelope, which in turn slightly lowered the ratio of indoor to outdoor PMs as well as the infiltrability for particles of all sizes. However, this intervention did not alter the distribution of particles within indoor environments. The most penetrated particles were observed in the size range 0.3-1.0 µm and then PM

IntroductionBivalve aquaculture has direct and indirect effects on plankton communities, which are highly sensitive to short-term (seasonal, interannual) and long-term climate changes, although how these dynamics alter aquaculture ecosystem interactions is poorly understood. MethodsWe investigate seasonal patterns in plankton abundance and community structure spanning several size fractions from 0.2 µm up to 5 mm, in a deep aquaculture embayment in northeast Newfoundland, Canada.ResultsUsing flow cytometry and FlowCam imaging, we observed a clear seasonal relationship between fraction sizes driven by water column stratification (freshwater input, nutrient availability, light availability, water temperature). Plankton abundance decreased proportionally with increasing size fraction, aligning with size spectra theory. Within the bay, greater mesozooplankton abundance, and a greater relative abundance of copepods, was observed closest to the aquaculture lease. No significant spatial effect was observed for phytoplankton composition. DiscussionWhile the months of August to October showed statistically similar plankton composition and size distribution slopes (i.e., food chain efficiency) and could be used for interannual variability comparisons of plankton composition, sampling for longer periods could capture long-term phenological shifts in plankton abundance and composition. Conclusions provide guidance on optimal sampling to monitor and assess aquaculture pathways of effects.

The size and composition of particulate matter (PM) are pivotal in determining its adverse health effects. It is important to understand PM's retention by plants to facilitate its atmospheric removal. However, the distinctions between the size and composition of naturally fallen PM (NFPM) and leaf-deposited PM (LDPM) are not well-documented. Here we utilize a single-particle aerosol mass spectrometer, coupled with a PM resuspension chamber, to analyze these differences. We find that LDPM particles are 6.8–97.3% larger than NFPM. Employing a neural network algorithm based on adaptive resonance theory, we have identified distinct compositional profiles: NFPM predominantly consists of organic carbon (OC; 31.2%) and potassium-rich components (19.1%), whereas LDPM are largely composed of crustal species (53.9–60.6%). Interestingly, coniferous species retain higher OC content (11.5–13.7%) compared to broad-leaved species (0.5–1.2%), while the levoglucosan content exhibit an opposite trend. Our study highlights the active role of tree leaves in modifying PM composition beyond mere passive capture, advocating for a strategic approach to species selection in urban greening initiatives to enhance PM mitigation. These insights provide guidance for urban planners and environmentalists in implementing nature-based solutions to improve urban air quality.

Catch, bycatch and discard information is important for the assessment and management of fisheries. Using Chinese pelagic tuna longline observer data from 2010 to 2018, we studied the catch composition in the Chinese pelagic tuna longline fisheries in Atlantic targeting bigeye tuna (Thunnus obesus) and bluefin tuna (Thunnus thynnus), and analyzed the survival status and discard rates of common bycatch species. A total of 55 species, including tunas, billfishes, sharks, sea turtles, cetaceans, seabirds, and other pelagic species, were observed. The results indicated that the catch composition of the Chinese pelagic tuna longline fishery targeting bigeye tuna was significantly different from that targeting bluefin tuna. The annual discard rates of common species decreased over this period. Discard rate by length and discard mortality for common species were varied among species. This is the first study to estimate catch, bycatch, and discard using Chinese pelagic tuna longline observer data in the Atlantic Ocean, which is important for the management of Chinese tuna longline fisheries in Atlantic Ocean.

Fillers play a decisive role in the mechanical properties of polymer composites. In this paper, different particle sizes of nitroguanidine were obtained to regulate the internal filler structure of triple‐base propellants (TBP) to improve their mechanical response in different environments. A series of morphological and structural characterizations on nitroguanidine (NQ) particles were conducted using techniques. The results indicated that the obtained NQ particles maintained a high level of crystalline quality while preserving their molecular integrity. The mechanical properties of TBP were systematically evaluated under various loading conditions, including cryogenic tensile, compressive, and impact loads, as well as dynamic thermomechanical effects. Additionally, three‐point bending simulations were employed to elucidate the mechanical responses and damage mechanisms. Under axial tensile and compressive loads, reducing the particle size of NQ significantly enhanced the tensile and compressive strength. The maximum tensile strength and compressive strength can reach 344.62 MPa and 104.79 MPa. Moreover, the compressive failure mode transitioned from cracking to axial shrinkage. Conversely, when subjected to radial bending loads, TBP exhibited contrasting behavior, including a decrease in the glass transition temperature from 84.73°C to 76.93°C and a non‐monotonic trend in impact strength (initially increasing from 4.96 to 8.85 kJ/m2 and then decreasing to 2.27 kJ/m2). This study provides valuable insights into the mechanical performance of TBP, supporting the development of high‐energy, high‐strength TBP formulations. Highlights: SEM analysis confirms the pronounced orientation effect of rod‐like NQ.The orientation and particle size of NQ decide TBP's radial impact resistance.Submicron NQ enhances the compression resistance property of TBP.Submicron NQ brings about a shift in the microscopic damage morphology of TBP. [ABSTRACT FROM AUTHOR]

All inorganic perovskite CsPbX3 (X = Cl, Br, and I) nanocrystals (NCs) have emerged as new semiconductor materials for light-emitting applications due to their high light absorption coefficient, tunable spectrum, and high photoluminescence quantum yields (PLQYs). However, owing to their burst nucleation and growth, the size distribution of CsPbX3 NCs prepared by the conventional homogeneous reaction system is wide, which affects their high color purity. Here, a heterogeneous reaction system was designed to prepare CsPbBr3 NCs with a narrow size distribution by controlling the nucleation and growth kinetics of CsPbBr3 NCs and eliminating the undesired Ostwald ripening effect. The synthesized CsPbBr3 NCs exhibit nearly a unit PLQY and a narrow size distribution. Benefiting from the tight ligands on the surface of NCs that can both stabilize the inorganic nuclei of CsPbBr3 NCs and passivate the Br vacancy defects of the NC surface, the obtained CsPbBr3 NCs have excellent optical stability. In particular, the PLQY of the CsPbBr3 NC colloidal dispersion can be as high as 86% even after 13 cycles of purification with methyl acetate. [ABSTRACT FROM AUTHOR]

Lignin fractionation aims at dividing the original lignin material into more uniform fractions that have the qualities desired for further processing of the material. Solvent fractionation is a versatile method that produces a soluble and an insoluble fraction with varying compositions, including molecular weight distribution, polydispersity (PDI), and phenolic hydroxyl (OHph) content. These properties are key factors in the further downstream applicability of lignin. Kraft, organosolv, and hydrolysis lignins were fractionated using multiple solvents and their water solutions with a single-stage fractionation protocol. The produced fractions were analyzed for their molecular size distribution and OHph content. Soluble fractions were discovered with desirable qualities, including a narrow size distribution (lowest PDI 1.4) and accumulation of OHph groups (up to 3.05 mmolOH/glignin). Three fractionation solvents, i.e., pure isopropanol, pure ethanol, and 30% γ-valerolactone, were found to produce solvent-specific soluble fractions that had relatively identical characteristic Mw, Mn, and PDI values regardless of the initial lignin material. This is crucially important new data that is beneficial for robust lignin applicability at industrial scale. Other important observations were made regarding water-alcohol solutions, as the increase in initial solid content resulted in changes in the composition of the fractions produced. Further applicability of the obtained fractions is examined in this paper. Patterns as well as differences between the three lignin materials were observed in their dissolution and the resulting compositions of the soluble fractions. This wide comparable dataset of industrially relevant solvents and lignin materials provides significant insight into the possibilities of lignin downstream processing. [ABSTRACT FROM AUTHOR]

Applying standard aerosol models for atmospheric correction in nearshore coastal waters introduces significant uncertainties due to their inability to accurately represent aerosol characteristics in these regions. To improve the accuracy of remote sensing reflectance ( R r s ) products in the nearshore waters of the Shandong Peninsula, this study develops an aerosol model based on aerosol data collected from the Mu Ping site in the coastal area of the Shandong Peninsula, enabling tailored atmospheric correction for this specific region. Given the pronounced seasonal variations in aerosol optical properties, monthly aerosol models were developed. The monthly aerosol model is derived using the average values of aerosol microphysical properties. Compared to the standard aerosol model, this model is more effective in characterizing the absorption and scattering characteristics of aerosols in the study area. Corresponding lookup tables for the aerosol model were created and integrated into the NIR-SWIR atmospheric correction algorithm. According to the accuracy evaluation indexes of RMSD, MAE, and UPD, it can be found that the atmospheric correction results of the aerosol model established in this paper are better than those of the standard aerosol model, especially in the 547 nm band. It demonstrates that the new aerosol model outperforms the standard model in atmospheric correction performance. With the increasing availability of aerosol observational data, the aerosol model is expected to become more accurate and applicable to other satellite missions. [ABSTRACT FROM AUTHOR]

A study was carried out in a waste sorting plant (WSP) located in France, treating dry recyclable household waste (DRHW) as well as dry recyclable commercial and industrial waste (DRCIW). Stationary and personal inhalable samples were collected in the WSP in order to investigate bioaerosols (sampling on a filter; 2 L/min and 10 L/min) and airborne dust (CIP; 10 L/min). The aim of the study was to assess the extent to which the measurement of concentration, species composition, and particle size distribution contributes to a better assessment of the biological risks associated with exposure. The results confirmed that waste and waste sorting activities are sources of airborne fungi. Indeed, ambient concentrations ranged from 7.3 × 103 to 8.5 × 105 colony-forming units (CFU)/m3 for culturable fungi and up to 4 mg/m3 for dust. Personal exposure to inhalable dust was found up to 3 mg/m3 for dust and ranged from 8.6 × 103 to 1.5 × 106 CFU/m3 for fungi. Airborne fungal communities were found to be dominated by the Penicillium genera in both bioaerosols and settled dust samples, followed by the Aspergillus, Cladosporium, Wallemia, Mucor, and Rhizopus genera. Fungi were carried by particles of aerodynamic diameters, mainly between around 2.0 and 10.0 µm. The findings dealing with size distribution and biodiversity of bioaerosols suggest that employees are exposed to complex bioaerosols during their work and help to make a finer diagnosis of the risks involved, which is often difficult in the absence of any occupational exposure limit (OEL) value for bioaerosols in general. [ABSTRACT FROM AUTHOR]

With the implementation of strict emission regulations and the use of cleaner fuels, there has been a considerable reduction in exhaust emissions. However, the relative contribution of tire wear particles (TWPs) to particulate matters is expected to gradually increase. This study conducted laboratory wear experiments on tires equipped on domestically popular vehicle models, testing the factors and particle size distribution of TWPs. The results showed that the content of tire wear particle emission was mainly ultrafine particles, accounting for 94.80% of particles ranging from 6 nm to 10 μm. There were at least two concentration peaks for each test condition and sample, at 10~13 nm and 23~41 nm, respectively. The mass of TWP emission was mainly composed of fine particles and coarse particles, with concentration peaks at 0.5 μm and 1.3–2.5 μm, respectively. Both the number and mass of TWPs exhibited a bimodal distribution, with significant differences in emission intensity among different tire samples. However, there was a good exponential relationship between PM10 mass emissions from tire wear and tire camber angle. The orthogonal experimental results showed that the slip angle showed the greatest impact on TWP emission, followed by speed and load, with the smallest impact from inclination angle. [ABSTRACT FROM AUTHOR]

Oxidation potential (OP), reflecting the redox activities of particle matter (PM), is considered an optimal measure to explain the biological effects of PM exposure. However, the size resolution of the relationship between OP and chemical composition in PM, especially how the relationship changes after respiratory exposure, has not been well investigated. In this study, size-resolved indoor PM10 samples were collected from a waste recycling plant from November to December 2021 using an Anderson eight-stage cascade impactor. OP, measured by a dithiothreitol (DTT) assay (defined as OPDTT), and elements, determined by inductively coupled plasma–mass spectrometry (ICP-MS) in size-resolved PM, were determined to check their relationships and the related human exposure risk. The results indicated that compared with PM0.4 and PM0.4–2.1, PM2.1–10 contributed the most to total OPDTT and its bound elements contributed the most to potential health risks, both before and after respiratory exposure. The association between OPDTT and the elements varied with PM size. Pearson correlation analysis showed that the PM0.4- and PM0.4–2.1-bound elements were moderate-to-strongly positively correlated with OPvDTT (r: 0.60–0.90). No significant correlation or dose–response relationship was found in PM2.1–10. After respiratory exposure, several PM0.4- and PM0.4–2.1-bound elements had a moderate-to-strongly positive correlation with deposition fluxes of OP (defined as OPFlux) (0.69–0.90). A generalized linear model analysis showed that the interquartile range (IQR) increase in the PM-bound elements (ng h−1) was associated with a 41.7–58.1% increase in OPFlux. Our study is a special case that enriches the knowledge of the association between OPDTT and the chemical composition of PM of different sizes, especially after respiratory exposure, but the generalizability of the findings to other settings or types of PM may be limited. The associations among OPDTT, other chemical compositions of PM, and human exposure risk merit further research. [ABSTRACT FROM AUTHOR]

The ability of water mist to mitigate blast loads has been widely recognized. However, the effects of the mean droplet diameter and volume fraction of water mist on the blast mitigation effect and underlying mechanisms have not been comprehensively examined. In this study, a three-dimensional numerical simulation based on the Euler-Lagrangian approach was carried out to study the dissipation process of blast wave energy and momentum by water mist, as well as the impact of varying mean droplet diameters (255-855 μm) and volume fractions (2.4x10-3-5.4x10-3) on blast mitigation. The numerical model incorporates interphase mass, momentum, and energy exchanges, as well as droplet breakup and size distribution. The results showed that the most efficient transfer of momentum and energy between the blast wave and water mist occurred at the air/water mist interface. Subsequently, the efficiency of momentum and energy transfer decreased as the blast wave propagated within the water mist due to the blast wave mitigation. The reduction in the mean droplet diameter and the increase in the volume fraction result in an increase in both the total the surface area and number of water droplets, thereby enhancing the efficiency of energy and momentum absorption by droplets and improving their ability to mitigate blasts. [ABSTRACT FROM AUTHOR]

The droplet breakups in an orifice jet mixer are studied to gain a deeper understanding of the breakup mechanism and establish breakup models used as population balance model source terms for accurate predictions. The breakup process and details are captured in situ using a high‐speed photomicrography system. Experiments are performed with different levels of pressure drop and mother droplet size. A complete breakup process consists of several different sub‐breakup events, hence the cascade breakup definition is adopted to determine statistical results. High breakup frequency is achieved under high pressure drop and small mother droplet size. The average number of daughter droplets is 102–105 and is positively correlated with the pressure drop and mother droplet size. The daughter droplet size distribution has a tailing phenomenon and is mainly affected by the pressure drop. New breakup models based on the above features are established and predict well with the experimental results. [ABSTRACT FROM AUTHOR]

Nanofibres have been widely used in many chemical engineering applications and their performance greatly depends on the size distribution of the nanofibres. Researchers have developed automated tools to determine nanofibre diameters, primarily using commercial MATLAB software package. However, no researchers have reported automatic processing of multiple images, which is essential to the consistency and accuracy of results. Nor has anyone reported nanofibre sizing using deep learning. Therefore, this paper reports an automated tool to measure the size distribution of electrospun nanofibres by simultaneous multi‐image processing. This tool determines the diameters of nanofibres using deep learning based on UNet model. Results show that the UNet‐based deep learning approach is more accurate than those obtained using existing methods, compared to experimental data. [ABSTRACT FROM AUTHOR]

The study is about the size distribution and health risks of polycyclic aromatic hydrocarbons (PAHs) in indoor environment of Xuanwei, Southwest China particle samples were collected by Anderson 8-stage impactor which was used to gather particle samples to nine size ranges. Size-segregated samples were collected in indoor from a rural village in Xuanwei during the non-heating and heating seasons. The results showed that the total concentrations of the indoor particulate matter (PM) were 757 ± 60 and 990 ± 78 μg/m3 in non-heating and heating seasons, respectively. The total concentration of indoor PAHs reached to 8.42 ± 0.53 μg/m3 in the heating season, which was considerably greater than the concentration in the non-heating season (2.85 ± 1.72 μg/m3). The size distribution of PAHs showed that PAHs were mainly enriched in PMs with the diameter <1.1 μm. The diagnostic ratios (DR) and principal component analysis (PCA) showed that coal and wood for residential heating and cooking were the main sources of indoor PAHs. The results of the health risk showed that the total deposition concentration (DC) in the alveolar region (AR) was 0.25 and 0.68 μg/m3 in the non-heating and heating seasons respectively. Throughout the entire sampling periods, the lifetime cancer risk (R) based on DC of children and adults varied between 3.53 ×10−5 to 1.79 ×10−4. During the heating season, the potential cancer risk of PAHs in adults was significant, exceeding 10−4, with a rate of 96%. [ABSTRACT FROM AUTHOR]