Enhancing Detection Frequency and Reducing Noise Through Continuous Structures via Release-Controlled Transfer Toward Light-Based Wireless Communication.

Organic photodetectors (OPDs) have received considerable attention owing to their superior absorption coefficient and tunable bandgap. The introduction of bulk-heterojunction (BHJ) structure aims to maximize charge generation, however, its response speed is constrained by the random distribution of donor and acceptor. Herein, a multiple-active layer design consisting of a single acceptor layer and a bulk-heterojunction layer (A/BHJ structure) is introduced, which combines the benefits of both the planar junction and the BHJ, improving photo-sensing. A transfer process is employed for this structure, which involves calculating the energy release rate at each interface, considering temperature and velocity. Consequently, the OPD with the A/BHJ structure is successfully fabricated through transfer printing, resulting in reduced dark current, superior detectivity (1.06 × 1013 Jones), and rapid response, achieved by creating a high hole injection barrier and suppressing trap sites within the interfaces. By thoroughly investigating charge dynamics in the structure, the A/BHJ structure-based OPD attains large bandwidth detection with high signal-to-noise. An efficient wireless data communication system with digital-to-analog conversion is showcased using the A/BHJ structure-based OPD.

Isothiocyanate-Based Microemulsions Loaded into Biocompatible Hydrogels as Innovative Biofumigants for Agricultural Soils.

Biofumigation was proposed as an alternative to synthetic pesticides for the disinfection of agricultural soils, in view of the biocidal effect of isothiocyanates (ITCs) released by some vegetal species, like Brassicaceae. However, biofumigation also presents limitations; thus, a novel and viable alternative could be the direct introduction of ITCs into agricultural soils as components loaded into biodegradable hydrogels. Thus, in this work, ITCs-based microemulsions were developed, which can be loaded into porous polymer-based hydrogel beads based on sodium alginate (ALG) or sodium carboxymethyl cellulose (CMC). Three ITCs (ethyl, phenyl, and allyl isothiocyanate) and three different surfactants (sodium dodecylsulfate, Brij 35, and Tween 80) were considered. The optimal system was characterized with attenuated ATR-FTIR spectroscopy and differential scanning calorimetry to study how the microemulsion/gels interaction affects the gel properties, such as the equilibrium water content or free water index. Finally, loading and release profiles were studied by means of UV-Vis spectrophotometry. It was found that CMC hydrogel beads showed a slightly more efficient profile of micelles' release in water with respect to ALG beads. For this reason, and due to the enhanced contribution of Fe(III) to their biocidal properties, CMC-based hydrogels are the most promising in view of the application on real agricultural soils.

CNG impact on combustion quality of a diesel engine fueled in diesel-gas mode.

The main objective of the paper is to reveal a few aspects related to combustion quality of a diesel engine fueled in diesel-gas mode with diesel fuel and compressed natural gas. The total amount of heat released per cycle will be higher when the engine is fueled in dual-fuel mode due to higher LHV and because of the gaseous state of CNG. For low and medium loads the total quality of heat released per cycle will increase with 10 % and for higher loads it will reach levels with 25 % higher. The heat release rate of the preformed mixture will double its value for low and medium loads and will reach thresholds up to 3.5 times higher (interval -15; -5°CA); admitting CNG into cylinder will help the preformed mixture to reach stoichiometric values and thus improving the fast combustion phase. Fueling the engine in dual fuel mode with diesel fuel and CNG will have a negative effect on the maximum heat release rate; there will be a 10 % drop in maximum HRR for low loads when the energetic substitution coefficient reaches 36 % and 14 % at high loads when the xc is 26 %. The gaseous state and a higher LHV of CNG will have a good impact on indicated mean effective pressure for all studied regimes when the engine is fueled in DG mode: for low and medium loads 30 % and for high loads 20 % increase will be recorded. Gaseous state of CNG will lead to a higher percentage of preformed mixture and thus the fast combustion phase will extend for longer periods for all studied regimes when the engine is fueled in DG mode (20 % longer for low and medium loads and 30 % for high loads). The diffusive combustion phase will become shorter due to a lower quantity of the main dose when CNG is injected into the intake manifold (10-15 % shorter for low loads and 7 % at high loads).

Role of Surface Tension on Heat Feedback and Power from Energetic Composites.

Heat feedback to the unburned reaction interface is an important controlling factor of the velocity of the reaction front and power delivery. In this paper, we investigate the effect of agglomerate surface tension and its relationship to surface residence time and heat feedback on the combustion characteristics by Si addition to an Al/KClO4 composite. Macroscopic imaging demonstrates a significant increase in burn rate with the addition of Si despite the fact that Si/KClO4 has a slightly lower energy density than Al/KClO4. Microscopic imaging coupled with three-color pyrometry reveals that molten liquid forms and evolves into spherical droplets on the burning surface, which are subsequently ejected from the surface. We find that the addition of Si results in a small increase in droplet size and a negligible impact on droplet temperature. However, the droplet formation rate on the surface is slower, leading to a significantly longer surface residence time. This leads to enhanced conductive heat feedback to the unburnt materials, thereby increasing the burn rate and energy release rate. We attribute the decreased droplet growth rate to the lowered surface tension of the liquid mixture with Si addition. This study highlights the crucial role of agglomerate physical property (e.g., surface tension) in influencing the combustion behavior of energetic composites.

Oxidation and spontaneous combustion characteristics of particulate coal under stress-heat-gas interactions.

Coal spontaneous combustion (CSC) is disturbed by complex downhole conditions. However, current research by scholars mainly focuses on the impact of single conditional disturbances on CSC, which is difficult to comprehensively characterize the oxidation and spontaneous combustion characteristics of granular coal in a complex environment. For this reason, a temperature-programmed gas chromatographer (TP-GC) hyphenated instrument and a C600 high-precision microcalorimeter was used for analysis. The variation rules of derived gas and oxidizing thermodynamic parameters in the coal oxidizing and heating process under stress-heat-gas interaction were obtained. The intrinsic action mechanism of stress-heat-gas interaction to increase the risk of spontaneous combustion of granular coal is described. The results showed that as the level of air leakage (AL) rate increased, the concentration of derived gases in the coal sample showed a "˄"-shaped trend, and the heat release intensity and heat release varied in stages, both reaching their peak at a leakage rate of 150 mL/min. Under different stress conditions, the heat release intensity and heat release of coal also reach their maximum at 150 mL/min, indicating a higher risk of spontaneous combustion of coal at 150 mL/min. As the stress increases, the coal­oxygen reaction is inhibited, leading to a decrease in the concentration of derived gases and a reduction in the average heat release of the coal sample. This indicates that particulate coal is prone to spontaneous combustion when subjected to high air leakage rate and low stress conditions. The experimental results provide a theoretical basis for the prevention of CSC under complex conditions.

Improving the estimation of direct release rates and transport processes from the Fukushima Daiichi Nuclear Power Plant accident using higher-resolution oceanic dispersion model.

A series of accidents at the Fukushima Daiichi Nuclear Power Station (F1NPS), following the 11 March 2011 earthquake and tsunami, resulted in the release of radioactive substances into the ocean. In particular, the release of large amounts of radioactive caesium has damaged the fishing industry, leading to voluntary restrictions on fishing and shipping. Oceanic dispersion simulations based on estimates of the pathways and fluxes of radioactive materials provide useful information for assessing the environmental impacts and formulating measures to mitigate the effects of the accident. For the direct release rate from the F1NPS site, an estimation method was developed using the results from nearby monitoring, and the seawater exchange rate was estimated in target volume using a numerical simulation. However, the influence of volume on the seawater exchange rate was not considered. Appropriate volumes must be considered when estimating the effects of future accidents. In addition, the directional coastal transport was underestimated in the simulations of the F1NPS accident because of the low resolution. To estimate the pathways and fluxes of radioactive material to the ocean and understand the distribution of the concentration of radioactive material based on ocean dispersion simulations, a study was conducted using a higher-resolution model. The horizontal resolution of the conventional ocean dispersion model Regional Ocean Modelling System (ROMS), was increased from 1 km to 200 m. The optimal settings of the seawater exchange rate were investigated, and the radioactive caesium transport process in the coastal direction was more accurately reflected. We found that the conventional volume for determining the seawater exchange rate, including the locations of release sources and observation points, is optimal. The validity of this finding was confirmed using experimental equations from previous oceanic tracer release experiments. To estimate future release rates, it an appropriate volume must be defined, for example, depending on the distance between the locations of the release sources and the observation point. In addition, improvements in the accuracy of the simulation of the coastal transport process were observed owing to the higher resolution, which increased reproducibility. However, with a horizontal resolution of 200 m, problems with repeatability near the harbours arose. A higher resolution, achieved using nesting or other methods, would be desirable to deal with releases smaller than those in the F1NPS accident.

Study on Fracture Characteristics of Layered Sandstone under Asymmetric Loading.

In engineering practice, layered rock masses often display obvious anisotropy while deforming and failing, and the failure mode directly impacts the engineering construction stability. In this study, the fracture failure load, fracture toughness, crack deflection angle, and failure mode of a layered rock mass under different fracture modes were analyzed by utilizing improved asymmetric semi-circular disc specimens. According to the constitutive model of transversely isotropic materials, the maximum tensile stress (MTS), maximum energy release rate (MERR), and maximum strain energy density (MSED) calculation formulas were modified, and the calculation formulas of the three prediction criteria under anisotropic materials were derived. The calculation results were compared with the experimental results. The results show that the fracture toughness and crack deflection angle were significantly affected by the weak bedding plane. As a result of applying the MTS criterion, the results are closer to the experimental results, providing a solid foundation for engineering deformation, failure, and fracture analyses.

Lyophilized Emulsions of Thymol and Eugenol Essential Oils Encapsulated in Cellulose.

Efforts to tap into the broad antimicrobial, insecticidal, and antioxidant activities of essential oils (EOs) are limited due to their strong odor and susceptibility to light and oxidation. Encapsulation of EOs and subsequent drying overcome these limitations and extend their applications. This study characterized freeze-dried (lyophilized) emulsions of eugenol (EU) and thymol (TY) EOs, encapsulated by chemically unmodified cellulose, a sustainable and low-cost resource. High-resolution scanning electron microscopy showed successful lyophilization. While the observed "flake-like" structure of the powders differed significantly from that of the emulsified microcapsules, useful properties were retained. Fourier transform infrared spectroscopy confirmed the presence of EOs in their corresponding powders and thermo-gravimetric analysis demonstrated high encapsulation efficiency (87-88%), improved thermal stability and resistance to evaporation, and slow EO release rates in comparison to their free forms. The lightweight and low-cost cellulose encapsulation, together with the results showing retained properties of the dried powder, enable the use of EOs in applications requiring high temperatures, such as EO incorporation into polymer films, that can be used to protect agricultural crops from microbial infections.

Low-cost cultivation of Nannochloropsis oceanica in newly designed photobioreactors and its productivity trends in semi-continuous cultivation under inland outdoor conditions.

Most marine microalgae are typically cultivated in coastal areas due to challenges in inland cultivation. In this 185 days experiment, Nannochloropsis oceanica was semi-continuously cultivated inland using different photobioreactors (PBRs). The newly designed 700-liter (L) PBR exhibited tolerance to seasonal changes compared to the 150-L PBRs. The innovative in-situ oxygen release rate (ORR) measurement method results indicated that ORR was influenced by light intensity and temperature. The optimal temperature range for N. oceanica growth was 14-25 â„ƒ, demonstrated cold tolerance and lipid accumulation at low temperatures. The maximum lipid content in 700-L and 150-L PBRs was 29 % and 28 %, respectively. Based on the average biomass productivity, the price of N. oceanica was $11.89 kg-1 (or $3.35 kg-1 based on maximum biomass productivity), which is cheaper than the current market price of $20.19 kg-1. From results, smaller PBRs at the same hydro electricity price are more cost-effective.

Fracture behavior of human cortical bone with high glycation content under dynamic loading.

The present study simulates the fracture behavior of diabetic cortical bone with high levels of advanced glycation end-products (AGEs) under dynamic loading. We consider that the increased AGEs in diabetic cortical bone degrade the materials heterogeneity of cortical bone through a reduction in critical energy release rates of the microstructural features. To simulate the initiation and propagation of cracks, we implement a phase field fracture framework on 2D models of human tibia cortical microstructure. The simulations show that the mismatch between the fracture properties (e.g., critical energy release rate) of osteons and interstitial tissue due to high AGEs contents can change crack growth trajectories. The results show crack branching in the cortical microstructure under dynamic loading is affected by the mismatches related to AGEs. In addition, we observe cortical features such as osteons and cement lines can prevent multiple cracking under dynamic loading even with changing the mismatches due to high AGEs. Furthermore, under dynamic loading, some toughening mechanisms can be activated and deactivated with different AGEs contents. In conclusion, the current findings present that the combination of the loading type and materials heterogeneity of microstructural features can change the fracture response of diabetic cortical bone and its fragility.

Composite alginate-based hydrogel delivery of antioxidant pumpkin protein hydrolysate in simulated gastrointestinal condition.

Pumpkin seeds are rich in protein (24-36.5%). Some of them are consumed as nuts, while others are regarded as waste and used for feeding animals. Protein hydrolysates from pumpkin seeds possess some bioactive properties, such as anti-oxidant activity. In this work, various composite alginate hydrogels contain Aloe vera, CMC, and tragacanth have been employed to protect PSPH against degradation in simulated gastrointestinal digestion (SGI) and regulate its release rate. The encapsulation efficiency of PSPH in plain alginate and beads with Aloe vera, CMC, and tragacanth combinations was 71.63, 75.63, 85.07, and 80.4%, respectively. The release rate of the plain alginate beads was %30.23 in the SGF and %52.26 in the SIF, and decreased in the composite-based beads. The highest decreasing rate in the antioxidant activity during SGI was observed in free PSPH, and the decreasing rate slowed down in the alginate-based composites. The swelling rate in plain alginate was %-23.43 and %25.43 in the SGF and SIF, respectively, and increased in the composite-based beads. The FTIR spectra of hydrogels before and after loading with PSPH showed identical absorption patterns and were similar to each other. Based on the data for SEM, it was revealed that substituting other polymers in polymer combinations with alginates resulted in a porosity reduction of the beads and smoother and more uniform surfaces. Based on the results, the combination of polysacchared with alginate could protect and increase the applicability of PSPH as a functional component in the food industry.

Fracture mechanics modeling of aortic dissection.

Aortic dissection, a critical cardiovascular condition with life-threatening implications, is distinguished by the development of a tear and its propagation within the aortic wall. A thorough understanding of the initiation and progression of these tears, or cracks, is essential for accurate diagnosis and effective treatment. This paper undertakes a fracture mechanics approach to delve into the mechanics of tear propagation in aortic dissection. Our objective is to elucidate the impact of geometric and material parameters, providing valuable insights into the determinants of this pivotal cardiovascular event. Through our investigation, we have gained an understanding of how various parameters influence the energy release rate for tear propagation in both longitudinal and circumferential directions, aligning our findings with clinical data.

Prospect of Gum Arabic-Cocoliposome Matrix to Encapsulate Curcumin for Oral Administration.

Curcumin is an antioxidant that can effectively eliminate free radicals. However, as its oral bioavailability is low, an effective delivery method is required. Phospholipid-based liposomes can encapsulate lipophilic drugs, such as curcumin, while liposome, cholesterol, and gum Arabic (GA) can enhance the internal and external stability of drug membranes. This present study used concentrations of cholesterol (Cchol) and GA (CGA), ranging from 0 to 10, 20, 30, and 40% as well as 0 to 5, 10, 15, 20, 30, and 40%, respectively, to encapsulate curcumin in a GA-cocoliposome (CCL/GA) matrix and test its efficacy in simulated intestinal fluid (SIF) and simulated gastric fluid (SGF). The absence of new characteristic peaks in the Fourier transform infrared (FTIR) spectra results indicate the presence of non-covalent interactions in the CCL/GA encapsulation. Furthermore, increasing the Cchol decreased the encapsulation efficiency (EE), loading capacity (LC), and antioxidant activity (IR) of the CCL/GA encapsulation but increased its release rate (RR). Conversely, increasing CGA increased its EE and IR but decreased its LC and RR. The two conditions applied confirmed this. Liposomal curcumin had the highest IR in SIF (84.081%) and the highest RR in SGF (0.657 ppm/day). Furthermore, liposomes loaded with 10% Cchol and 20% CGA performed best in SIF, while those loaded with 10% Cchol and 30% CGA performed best in SGF. Lastly, the CCL/GA performed better in SIF than SGF.

Comparison between using inlet circular jet and elliptic jet in combustion chamber by using twin jet flow propane and methanol.

The current work aimed to improve the combustion behavior of a non-premixed twin-jet inlet. The effect of fuel and air inlet shape under different velocities was studied using ANSYS as the process takes place in species transport and finite rate/eddy dissipation, and the flow is considered to be turbulent. Two different shapes (circular-circular and circular-elliptic inlet jets) were investigated, and the results show that the behavior and intensity of the fire are affected by variations in the speed and, geometry of the inlet which affects temperature, heat release rate, combustion efficiency, and equivalent ratios. The optimum air/fuel velocities were found to be 2.5/1.5 with circular-circular inlet jets.

Trends in Rescue and Rehabilitation of Marsupials Surviving the Australian 2019-2020 Bushfires.

The 2019-2020 Australian bushfire season had a devastating impact on native wildlife. It was estimated that 3 billion native animals were impacted by the fires, yet there are few estimates of the number of animals that were rescued and rehabilitated post-fire. Focusing on the state of New South Wales (NSW) and Kangaroo Island, South Australia, we used a case study approach to determine the number of marsupials that were reported rescued due to the 2019-2020 bushfires in these areas and analysed species-specific trends in rescue and release success. In NSW, we found 889 reports of fire-affected marsupials in 2019-2020, mostly comprising kangaroos and wallabies (macropods; n = 458), koalas (n = 204), and possums (n = 162), with a smaller number of wombats (n = 43) and other marsupial species. Most reports of fire-affected marsupials occurred 6-8 weeks after fire ignition, and there was no difference in temporal frequency of rescues between marsupial groups. For the three main groups, the probability of survival and subsequent release differed, with macropods having the lowest probability of release after rescue (0.15 ± 0.04) compared to koalas (0.47 ± 0.04) and possums (0.55 ± 0.10). The type of injury was the main predictor of survival during rehabilitation for all three marsupial groups, with those malnourished/moribund or with traumatic injuries less likely to survive rehabilitation. Death or euthanasia occurred on the day of rescue for 77% of macropods, 48% of possums and 15% of koalas. Koalas most often died during rehabilitation rather than on the day of rescue, with 73% either dying or being euthanised between day 1 and 30 post-rescue, representing a potential welfare concern. On Kangaroo Island, koalas were the most frequently rescued marsupial species; most euthanasia cases and deaths occurred in a hospital, whereas other marsupials were mostly euthanised at triage. In both jurisdictions, koalas were over-represented while possums were under-represented relative to baseline population densities and wildlife rescue trends in the years before the 2019-2020 bushfires. These species differences in presentation post-fire warrant further investigation, as do the differences in triage, survival and release outcomes. It is hypothesised that the high intensity and large scale of the 2019-2020 fires impeded marsupial fire evasion tactics, as evidenced by the small number of animals found for rescue, and the differing rates of presentation relative to underlying population densities for the main marsupial groups. Based on our findings, there is a need for detailed record keeping and data sharing, development of consistent and evidence-based triage, treatment and euthanasia guidelines and deployment of trained wildlife emergency rescue teams with advanced search techniques to minimise animal suffering where safe to do so.

Multi-layer encapsulation of pumpkin (Cucurbita maxima L.) seed protein hydrolysate and investigating its release and antioxidant activity in simulated gastrointestinal digestion.

Because of their high protein content, easy access and low cost, pumpkin seeds are a valuable raw material for the preparation of antioxidant protein hydrolysates. Micro-coating is an effective method to protect bioactive compounds against destruction. In order to strengthen the alginate hydrogel network loaded with pumpkin seed protein hydrolysate (PSPH), CMC was added as part of its formulation in the first step, and chitosan coating was used in the second step. Then, swelling amount, release in the simulated gastrointestinal environment (SGI), antioxidant activity after SGI, Fourier transform infrared spectroscopy (FTIR), zeta potential, dynamic light scattering (DLS), polydispersity index (PDI) and scanning electron microscopy (SEM) of the samples were evaluated. The results showed that, the swelling amount of the chitosan-alginate hydrogel was lower than the chitosan-alginate-CMC sample, and with the increase in chitosan concentration, the swelling amount decreased. The release amount in the chitosan-alginate sample was higher than that in the chitosan-alginate-CMC sample, and with the increase in chitosan concentration, the release rate decreased. Also, the amount of release increased with the passage of time. The highest antioxidant activity belonged to the chitosan-alginate sample in SGI, and it increased with increasing the chitosan concentration. All findings demonstrated that the use of multi-component hybrid systems is a useful method for the protection of bioactive compounds against destruction, their antioxidant activities and their release behavior.

Exhaust flow calibration for a large-scale calorimetry system using tracer gas dilution.

Exhaust flow measurements are a significant source of uncertainty for measurements of heat release rate in large-scale fire experiments. Irregular flow distributions are often present in the exhaust ducts making it difficult to measure flow accurately. Tracer gas dilution (TGD), a measurement method for volume flow, is not sensitive to flow distribution and has been applied to calibrate flow measurement devices at the exhaust ducts of a large-scale open calorimetry system. The in-line calibration reduced the bias in the exhaust flow measurement by as much as 6% improving the overall measurement accuracy of the heat release rate. Experimental results provide evidence that the flow calibration is an improvement over the accepted practice of developing a flow correction from the comparison of oxygen consumption calorimetry with the heat output from a gas burner. The flow calibration is valid for a wide range of flow conditions and decouples the oxygen consumption calorimetry measurement from any error in determining the heat release rate from the gas burner.

Spatiotemporal modeling of nano-delivered chemotherapeutics for synergistic microwave ablation cancer therapy.

BACKGROUND AND OBJECTIVE: The effectiveness of current microwave ablation (MWA) therapies is limited. Administration of thermosensitive liposomes (TSLs) which release drugs in response to heat has presented a significant potential for enhancing the efficacy of thermal ablation treatment, and the benefits of targeted drug delivery. However, a complete knowledge of the mechanobiological processes underlying the drug release process, especially the intravascular drug release mechanism and its distribution in response to MWA needs to be improved. Multiscale computational-based modeling frameworks, integrating different biophysical phenomena, have recently emerged as promising tools to decipher the mechanobiological events in combo therapies. The present study aims to develop a novel multiscale computational model of TSLs delivery following MWA implantation. METHODS: Due to the complex interplay between the heating procedure and the drug concentration maps, a computational model is developed to determine the intravascular release of doxorubicin from TSL, its transvascular transport into the interstitium, transport in the interstitium, and cell uptake. Computational models can estimate the interplays among liposome and drug properties, tumor perfusion, and heating regimen to examine the impact of essential parameters and to optimize a targeted drug delivery platform. RESULTS: Results indicated that the synergy of TSLs with MWA allows more localized drug delivery with lower side effects. The drug release rate and tumor permeability play crucial roles in the efficacy of TSLs during MWA treatment. The computational model predicted an unencapsulated drug lime around the ablated zone, which can destroy more cancer cells compared to MWA alone by 40%. Administration of TSLs with a high release rate capacity can improve the percentage of killed cancer cells by 24%. Since the heating duration in MWA is less than 15 min, the presented combination therapy showed better performance for highly permeable tumors. CONCLUSION: This study highlights the potential of the proposed computational framework to address complex and realistic scenarios in cancer treatment, which can serve as the future research foundation, including advancements in nanomedicine and optimizing the pair of TSL and MWA for both preclinical and clinical studies. The present model could be as a valuable tool for patient-specific calibration of essential parameters.

Distribution and release of PFAS from AFFF-impacted asphalt: How does it compare to concrete?

Aqueous film forming foam (AFFF)-impacted asphalt and concrete may serve as potential secondary sources of per- and polyfluoroalkyl substances (PFAS) to the environment through surficial leaching. We aimed to understand the vertical distribution and surficial release of PFAS from AFFF-impacted asphalt and concrete cores collected from various locations (∼10-70 m distance between samples). Among the PFAS analyzed, 6:2 FTS was observed as having the highest concentration in the surface layer (0 - 0.5 cm) of concrete (225 µg kg-1) and in the runoff from the concrete (2600 ng L-1). PFOS was detected at the highest concentration in the surface layer (0 - 0.5 cm) of asphalt (47 µg kg-1) and associated runoff (780 ng L-1). The total mass of PFAS released during three rainfall simulations accounts for a fraction of the total mass in the surface layer (0 - 0.5 cm), ranging from 0.10 - 9.8% and 0.078 - 2.4% for asphalt and concrete cores, respectively. Asphalt exhibited a higher release rate than concrete, demonstrated by the higher total release coefficient of PFAS (4 - 16 m-2) compared to that of concrete cores (1 - 5 m-2). These results suggested that, similar to concrete, AFFF-impacted asphalt may be a secondary source of PFAS to the environment.

Effects of Pyrolysis Temperature and Acid-Base Pre-Treatment on the Synthesis of Biochar-Based Slow-Release Selenium Fertilizer and Its Release in Soil.

Plant-derived selenium is an important source of selenium (Se) for humans, which, however, has been restricted by a low content of Se in soil. Traditional Se fertilizers have tended to result in low selenium utilization. Thus, it was necessary to develop a new slow-release material to control Se fertilizer release. In this study, biochar pyrolyzed at 300 °C and 800 °C was cross-linked with polyethyleneimine (PEI) after being treated with HNO3 or NaOH (which were labeled Acid-W300, Acid-W800, Alkali-W300, and Alkali-W800). The results showed that the maximum adsorption capacities of Acid-W300, Alkali-W300, Acid-W800, and Alkali-W800 were 329.16 mg/g, 321.93 mg/g, 315.04 mg/g, and 344.33 mg/g, respectively. Among them, Acid-W800 and Alkali-W800 were mainly imine- and amide-bonded with SO32-, while Acid-W300 and Alkali-W300 were loaded with SO32- by forming the C-Se bonding as well as through imine- and amide-bonding. The release of four biochar-based selenium fertilizers in the red soil and brown soil extracts conformed to the pseudo-second-order kinetic model. The release rate and release amount of four biochar-based selenium fertilizers in the red soil extract were higher than those in the brown soil extract. Alkali-W800-Se had a higher proportion of Se-exchangeable release, accounting for 87.5% of the total loaded selenium, while Acid-W300-Se had the lowest proportion at 62.2%. However, the Se releases of Alkali-W800-Se were more than 42.49% and 37.67% of the total Se-loading capacity during 5 days of continuous red soil extraction and brown soil extraction, respectively. Acid-W300-Se released less than 20% of the total Se-loading capacity. Thus, Acid-W300-Se was the recommended slow-release Se fertilizer in red soil and brown soil.