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The growing volume of plastics derived from electronic waste (e-waste) underscores the imperative for environmentally sustainable strategies for the management of this waste. In light of the paramount importance of this issue, a pilot demonstrator for the decontamination of polymers containing Brominated Flame Retardants (BFRs) has been developed. The objective is to investigate the potential for decontaminating BFR-containing polymers from e-waste via UV-visible irradiation using a rotatory laboratory pilot operating under primary vacuum conditions. This report focuses on binary model blends composed of 90 weight% (wt%) poly(Acrylo-Butadiene-Styrene) (ABS) pellets and 10 wt% Deca-Bromo-Diphenyl Ether (DBDE), which is one of the most toxic BFRs. The efficiency of the irradiation process was evaluated as a function of pellet diameter and irradiation time using Fourier Transform InfraRed spectroscopy (FTIR) and High-Resolution Laser Desorption/Ionization Mass Spectroscopy (HR-LDI-MS). As a consequence, ABS + DBDE achieved a decontamination efficiency of 97% when irradiated with pellets of less than 1 mm in diameter for a period of 4 h. Additionally, the thermal behavior of the irradiated samples was investigated through thermogravimetric analysis and differential scanning calorimetry. It was thus established that the application of UV-visible irradiation had no significant impact on the overall thermal properties of ABS.

In order to protect human health and the environment, several regulations have been introduced in recent years to reduce or even eliminate the use of some brominated flame retardants (BFRs) due to their toxicity, persistence and bioaccumulation. Dispersions of these BFRs in polymers are widely used for various applications. In this report, four different brominated molecules, decabromodiphenyl ether (DBDE), hexabromocyclododecane (HBCDD), decabromodiphenyl ethane (DBDPE) and tris(tribromophenoxy)triazine (TTBPT), were dispersed in the solid matrix of an industrial polymer, high impact polystyrene (HIPS). The possibility of degradation of these BFRs within HIPS under UV–visible irradiation in ambient air was investigated. The degradation kinetics of DBDE and HBCDD were followed by Fourier transform infrared spectroscopy (FTIR) and high-resolution two-step laser mass spectrometry (L2MS). The thermal properties of the pristine and irradiated polymer matrix were monitored by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), which showed that these properties were globally preserved. Volatile photoproducts from the degradation of DBDE, DBDPE and TTBPT were identified by headspace gas chromatography/mass spectrometry analysis. Under the chosen experimental conditions, BFRs underwent rapid degradation after a few seconds of irradiation, with conversions exceeding 50% for HIPS/DBDE and HIPS/HBCDD systems. [ABSTRACT FROM AUTHOR]

Electron Beam (EB) irradiation was utilized to decontaminate model systems of industrial polymers that contain a brominated flame retardant (BFR). Acrylonitrile-butadiene-styrene (ABS) and Polycarbonate (PC) are two types of polymers commonly found in Waste Electrical and Electronic Equipment (WEEE). In this study, these polymers were exposed to EB irradiation to degrade DecaBromoDiphenylEther (DBDE), one of the most toxic BFRs. Fourier-transform infrared spectroscopy analysis demonstrated an 87% degradation rate of DBDE for the ABS-DBDE system and 91% for the PC-DBDE system following an 1800 kGy irradiation dose. Thermal analysis using Differential Scanning Calorimetry revealed the presence of crosslinking in ABS and a minor reduction in the glass transition temperature of PC after EB processing. Polymers exhibited thermal stability after photolysis, as indicated by thermogravimetric analysis. In summary, EB irradiation had no impact on the overall thermal properties of both polymers. High-resolution mass spectrometry analysis has confirmed the debromination of both ABS-DBDE and PC-DBDE systems. Therefore, the results obtained are promising and could offer an alternative approach for removing bromine and other additives from plastic E-waste.

The growing volume of plastics derived from electronic waste (e-waste) underscores the imperative for environmentally sustainable strategies for the management of this waste. In light of the paramount importance of this issue, a pilot demonstrator for the decontamination of polymers containing Brominated Flame Retardants (BFRs) has been developed. The objective is to investigate the potential for decontaminating BFR-containing polymers from e-waste via UV-visible irradiation using a rotatory laboratory pilot operating under primary vacuum conditions. This report focuses on binary model blends composed of 90 weight% (wt%) poly(Acrylo-Butadiene-Styrene) (ABS) pellets and 10 wt% Deca-Bromo-Diphenyl Ether (DBDE), which is one of the most toxic BFRs. The efficiency of the irradiation process was evaluated as a function of pellet diameter and irradiation time using Fourier Transform InfraRed spectroscopy (FTIR) and High-Resolution Laser Desorption/Ionization Mass Spectroscopy (HR-LDI-MS). As a consequence, ABS + DBDE achieved a decontamination efficiency of 97% when irradiated with pellets of less than 1 mm in diameter for a period of 4 h. Additionally, the thermal behavior of the irradiated samples was investigated through thermogravimetric analysis and differential scanning calorimetry. It was thus established that the application of UV-visible irradiation had no significant impact on the overall thermal properties of ABS. [ABSTRACT FROM AUTHOR]

The determination of the qualitative and quantitative content of the main active substance of a microlitic medicinal product is necessary to confirm its good quality. The purpose of scientific research: check the suitability of existing methods for the qualitative and quantitative determination of ambroxol hydrochloride, as indicated in the monographs of the SPU «Ambroxol hydrochloride, substance» and «Ambroxol tablets», for the possibility of qualitative and quantitative determination of ambroxol hydrochloride in various finished medicines and to determine the possibility of using an alternative solvent in individual methods. The substance of Ambroxol hydrochloride and four finished dosage forms with the active substance Ambroxol hydrochloride were used: injection solution 7.5 mg/ml in ampoules, 30 mg tablets, syrup 15 mg/5 ml and a combined drug that contains 30 mg Ambroxol hydrochloride and acetylcysteine 200 mg in powder form for oral suspension in sachet. The study was carried out using a UV spectrophotometer, an Agilent 1200 liquid chromatograph with a diode array detector (chromatographic column ‒ Inertsil ODS-3V, 250×4.6 mm, particle size 5 μm), thin-layer chromatography (chromatographic plate ‒ TLC Silicagel 60 F254). The suitability of using an alternative solvent with a 0.1 M hydrochloric acid solution to identify the substance of ambroxol hydrochloride by UV spectrophotometry, as indicated in the SPU monograph for Ambroxol hydrochloride, substance, has been confirmed. As a result of the study of finished dosage forms, it was determined that the identification of ambroxol hydrochloride with a 0.1 M hydrochloric acid solution is possible only for injection and tablets. For syrup and powder for oral suspension, it was determined that the use of such a technique for the identification of ambroxol hydrochloride is impossible. According to the results of the quantitative determination of ambroxol hydrochloride according to the methodology of the SFU «Ambroxol tablets» monograph in different dosage forms, it is possible to conclude that this technique is suitable for such forms as injection and syrup. For the quantitative determination of ambroxol hydrochloride in a preparation in the form of a powder for oral solution, this technique is unsuitable. Using thin layer chromatography, it is possible to identify Ambroxol hydrochloride for such forms as tablets and injection. However, the unsuitability of this methodology for such forms of as powder for oral suspension and syrup. It was confirmed that the experimentally selected technique using the method of high performance liquid chromatography is suitable for the qualitative and quantitative determination of ambroxol hydrochloride in the finished drugs that are selected for this work, and can be used to test finished drugs with the same composition of active and excipients. It was found that the method of high performance liquid chromatography allows not only to identify and quantify ambroxol hydrochloride, but also to determine the presence of some excipients.

The growing interest in phase-change materials (PCM) is related to their possible role in thermal energy storage and thermal management. The choice of materials depends strongly on the required temperature range, whereas the latent heat of solid–liquid phase transition has to be as high as possible. Among other organic PCM, sugar alcohols have gained some attention due to their availability and certain advantageous properties. However, the thermal processes in these materials still require investigation. In the present work, we focused on the materials with solid–liquid phase change within 80 °C–100 °C. A comprehensive literature survey was conducted to elucidate the available sugar alcohols relevant to this range. It was found that the use of pure materials of this type is not very practical, because of their scarcity in the required range and their specific features, like difficulties with crystallization and solidification. On the other hand, based on the literature, we have discerned three eutectic mixtures of erythritol with other organic materials, namely, erythritol–xylitol, erythritol–urea and erythritol– trimethylolethane (TME). In all those cases, it is remarkable that while the components commonly have rather high melting temperatures, the eutectic mixtures had the phase transitions in the required range. Still, each of these mixtures has its own peculiar features, especially at cooling and solidification. An extensive experimental study was performed to provide detailed visualization of these major processes. The results revealed the melting temperature and latent heat of the mixtures to be: 84 °C and 190 J g ^−1 for erythritol–xylitol, 82 °C and 227 J g ^−1 for erythritol–urea. Erythritol–TME has two phase transitions at 82 °C and 97 °C, with total latent heat of 198 J g ^−1 . Based on the present findings, the erythritol–urea mixture is the best PCM candidate for the melting range within 80 °C–100 °C.

Combustion of hydrocarbons produces both particulate- and gas-phase emissions responsible for major impacts on atmospheric chemistry and human health. Ascertaining the impact of these emissions, especially on human health, is not straightforward because of our relatively poor knowledge of how chemical compounds are partitioned between the particle and gas phases. Accordingly, we propose coupling a two-filter sampling method with a multi-technique analytical approach to fully characterize the particulate- and gas-phase compositions of combustion by-products. The two-filter sampling method is designed to retain particulate matter (elemental carbon possibly covered in a surface layer of adsorbed molecules) on a first quartz fiber filter while letting the gas phase pass through and then trap the most volatile components on a second black-carbon-covered filter. All samples thus collected are subsequently subjected to a multi-technique analytical protocol involving two-step laser mass spectrometry (L2MS), secondary ion mass spectrometry (SIMS), and micro-Raman spectroscopy. Using the combination of this two-filter sampling–multi-technique approach in conjunction with advanced statistical methods, we are able to unravel distinct surface chemical compositions of aerosols generated with different set points of a miniCAST burner. Specifically, we successfully discriminate samples by their volatile, semi-volatile, and non-volatile polycyclic aromatic hydrocarbon (PAH) contents and reveal how subtle changes in combustion parameters affect particle surface chemistry.

Phase change materials (PCMs) present opportunities for efficient thermal management due to their high latent heat of melting. However, a fundamental challenge for PCM cooling is the presence of a growing liquid layer of relatively low thermal conductivity melted PCM that limits heat transfer. Dynamic phase change material (dynPCM) uses an applied pressure to pump away the melt layer and achieve a thin liquid layer, ensuring high heat transfer for extended periods. This paper investigates heat transfer during dynPCM cooling when the heated surface has extended features made from high thermal conductivity copper (Cu). Using experiments and finite element simulations, we investigate the heat transfer performance of dynPCM paraffin wax on finned Cu surfaces. A total of 102 transient temperature measurements characterize the performance of dynPCM with extended surfaces and compare the performance with other cooling methods including hybrid PCM and air cooling. The study examines the effects of fin geometry, applied power (20–65 W), and pressure (0.97–12.5 kPa). For dynPCM on a finned surface and a heating power of 65 W, the thermal conductance is 0.45 W/cm2-K, compared to 0.22 W/cm2-K for dynPCM on a flat surface and 0.10 W/cm2-K for hybrid PCM. The heat transfer is highest at the fin tips where the melt layer is thinnest, providing valuable design guidelines for future high performance dynPCM cooling technologies. [ABSTRACT FROM AUTHOR]

In nature and engineering, fluid movements involving swirling patterns, or vortices, are common occurrences. Some flows involve free-surface vortices that can potentially lead to a phenomenon termed gas entrainment (GE). There is no validated tool that can predict the free-surface profile of the gas core prior and subsequent to the GE. This study focuses on experimental and numerical investigation of flows with unsteady free-surface vortices that can potentially lead to gas entrainment. An extensive experimental work, performed in a dedicated experimental setup built in the present study, yields two main contributions. First, a new GE onset criterion, based on implementing dimensional analysis to the experimental results, is developed. The onset criterion is found to be suitable also for other experiments in the literature. Second, the experimental acquisition of the free-surface profiles, obtained with a high-speed camera, is used for validating the numerical approach. This three-dimensional numerical tool incorporates Large Eddy Simulation to capture turbulence, with Volume-of-Fluid approach to simulate free-surface profiles. The model predicts with high accuracy the free-surface profiles in cases with and without GE, observed experimentally. Then, the detailed simulation results for this type of flows are analyzed quantitatively for the first time in the available literature, using radial, axial, and tangential velocity components. The present study sheds new light on free-surface vortex flows, in general. The experimental and numerical achievements in this study can serve as a tool both to predict the free-surface flow profiles with high accuracy and to prevent gas entrainment in the engineering systems. [ABSTRACT FROM AUTHOR]

"Legalisation" does not specify a policy. Cannabis could be made available for use by adults under a wide variety of conditions: cheap or expensive, offered by for-profit enterprises, by not-for-profits (including consumer co-operatives), as a state monopoly (for production or sales or both), or even on a "grow-your-own" basis. It could be cheap (as it would be in a free market) or expensive (due to taxes or minimum pricing). Marketing efforts could be free or restrained. Users could be "nudged" toward temperate use - for example, through a system of user-set but enforceable periodic purchase limits - or left to their own devices. Policy-makers should keep in mind Pareto's Law, which applies to cannabis consumption: about four-fifths of consumption is accounted for by about one-fifth of consumers. That fact will drive the commercial strategies of for-profit producers and sellers, and should focus the attention of public agencies on the risks and harms to the heavy-using minority. Uncertainties abound, and consequently policies should be designed to allow the system to learn from experience. But it is possible to try to predict and evaluate – albeit imperfectly – the likely consequences of proposed policy changes and to use those predictions to choose systems of legal availability that would result in better, rather than worse, combinations of gain and loss from the change.

To accommodate societal electrification and decarbonization, renewable energy resources continue to expand their share of the global energy market. The intermittency of renewable energy technologies as well as the high power density of modern electrified platforms necessitates the need for both efficient thermal management and high-density thermal storage. Phase change materials are a promising passive thermal energy storage solution. However, difficulties with efficient system implementation stemming from the inherent melt pool formation hinder their potential. We develop an innovative strategy, termed dynamic phase change material "dynPCM," to address this thermal transport issue by ensuring a constant, thin, melt layer. We analyze the fundamental limits of dynPCMs, characterize the peak achievable heat flux and energy/power densities, estimate the power consumption of dynPCM systems, and investigate the fundamental physics which govern dynPCM behavior. We show that dynPCM can eliminate the classical trade-off seen between energy density and power density and achieve ultrahigh heat fluxes, ∼105 W/cm2, with heat flux-to-required power ratios as high as ∼107. We also demonstrate achievable power densities as high as ∼100 W/cm3 at energy densities as high as ∼10 kJ/cm3. Throughout this work, we develop a methodology to evaluate the operating limits, enabling adaptation of the dynPCM system concept to a variety of applications and industries. [ABSTRACT FROM AUTHOR]

Background: Adult Basic Education (ABE) is the national system that offers adults with low literacy and/or limited English with educational services in reading, writing, math, technology, and communications from basic levels to high school equivalency, with specialty programs in transition to community colleges and family literacy. Brief Description of Activity: To show the role of ABE in increasing health literacy in low literate and/or limited English populations through partnership with community health organizations (CHOs). Implementation: This article was developed through a collaborative thought process over a period of 8 months with experts from the field of ABE in development of health literacy within low literate and/or limited English populations. It describes the research that links low literacy and/or limited English with poor health, and introduces how ABE and CHOs have addressed these issues together. It also introduces research on the impact on learners of integrating health into ABE. Results: ABE learners have consistently shown a strong interest in learning about health for themselves and their families, and health content energizes ABE instruction. Learners report improvements of basic health knowledge, their confidence communicating with health care professionals, enhanced self-efficacy, and intention to make changes in such health behaviors as diet and tracking blood pressure. Partnerships between ABE programs and their local CHOs strengthen the teaching/learning process and can be mutually beneficial. ABE provides access to hard-to-reach populations, a safe learning environment, and teaching expertise. CHOs provide health expertise, preventive health screenings, and access to treatments. Lessons Learned: The link between low literacy and poor health is no longer disputed. ABE programs and many CHOs share a common mission and commitment to serving vulnerable populations. Stronger partnerships between these organizations should be viewed as a viable strategy for addressing health disparities. A coordinated effort of community health centers across the nation is required to meaningfully respond to health disparities as a national social issue.

Electron Beam (EB) irradiation was utilized to decontaminate model systems of industrial polymers that contain a brominated flame retardant (BFR). Acrylonitrile-butadiene-styrene (ABS) and Polycarbonate (PC) are two types of polymers commonly found in Waste Electrical and Electronic Equipment (WEEE). In this study, these polymers were exposed to EB irradiation to degrade DecaBromoDiphenylEther (DBDE), one of the most toxic BFRs. Fourier-transform infrared spectroscopy analysis demonstrated an 87% degradation rate of DBDE for the ABS-DBDE system and 91% for the PC-DBDE system following an 1800 kGy irradiation dose. Thermal analysis using Differential Scanning Calorimetry revealed the presence of crosslinking in ABS and a minor reduction in the glass transition temperature of PC after EB processing. Polymers exhibited thermal stability after photolysis, as indicated by thermogravimetric analysis. In summary, EB irradiation had no impact on the overall thermal properties of both polymers. High-resolution mass spectrometry analysis has confirmed the debromination of both ABS-DBDE and PC-DBDE systems. Therefore, the results obtained are promising and could offer an alternative approach for removing bromine and other additives from plastic E-waste. [ABSTRACT FROM AUTHOR]