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The goal of the presented work was to find the most favorable conditions for the synthesis and stabilization of chemically pure ettringite and monosulfate. The reaction was carried out by mixing pure tricalcium aluminate (C3A) and gypsum (C S ¯ H2) in an excess amount of water. The impact of hydration time (2–7 days), C3A:C S ¯ molar ratio (1:1–1:3) and water vapor pressure of the selected drying agents (anhydrite-III and supersaturated CaCl2 solution) on the phase composition of the products was evaluated. After 7 days of hydration, either ettringite or monosulfate was obtained as the main product, depending on the C3A:C S ¯ molar ratio. The synthesis carried out at a C3A:C S ¯ molar ratio of 1:3 produced pure ettringite. In the case of the sample characterized by the ratio of 1:1 (typical of monosulfate), a considerable portion of ettringite (27.9%) was present in the final products along the AFm phase. Therefore, a different synthesis method has to be selected in order to obtain pure monosulfate. The results showed that thermal analysis, X-ray diffractometry and FTIR spectroscopy can be used to distinguish the characteristic features of ettringite and monosulfate. [ABSTRACT FROM AUTHOR]

The disposal and reutilization of the enormous amounts of slurry-like mud (MS) dredged from navigation channel construction, ecological dredging, and other construction activities have been receiving increasing attention. In this paper, a flocculation–solidification–high-pressure filtration combined method (FSHCM) is used to treat MS, and the consolidation characteristics of The SHCM-treated MS are studied by conducting a series of one-dimensional consolidation compression tests. Various parameters, including the dosage of the curing agent, initial water content, and dry weight of the MS, are systematically analyzed to evaluate their influence on the consolidation behavior. The experimental results demonstrate that higher curing agent and initial water contents enhance the structural yield stress and compressive resistance, while increased dry weight decreases the structural yield stress but increases the compressive strain and void ratio. As the curing age increases, the ability of the FSHCM-treated MS to resist compressive deformation is further enhanced. In addition, the compressibility of the mud cake samples changes significantly at the yield point. This study has practical guiding significance for the optimal design and long-term application of FSHCM-treated MS. [ABSTRACT FROM AUTHOR]

Zirconia nanocrystals as catalysts for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide have received significant interest recently. In this paper, three zirconia-based catalysts presenting different monoclinic and tetragonal phase contents are prepared and characterized by X-ray diffraction (XRD), N2 adsorption–desorption, transmission electron microscopy (TEM), and temperature-programmed desorption of NH3 and CO2 (NH3-TPD and CO2-TPD). The catalytic performances of these solids are evaluated in terms of DMC production. This production is low when using the bare zirconias, but it is significantly increased in the presence of 1,1,1-trimethoxymethane (TMM) playing the role of a dehydrating agent, which shifts the thermodynamic equilibrium. Moreover, the production of DMC is further improved by adding a second solid catalyst (cocatalyst), the molecular sieve 13X, to accelerate the hydration of TMM. Hence, the molecular sieve 13X plays a dual role by trapping water molecules formed by the reaction of DMC synthesis and providing strong acidic sites catalyzing TMM hydrolysis. To the best of our knowledge, the combination of two solid catalysts in the reaction medium to accelerate the water elimination to obtain higher DMC production from CO2 and methanol has never been reported. [ABSTRACT FROM AUTHOR]

Approximately two billion people worldwide lack access to clean drinking water, negatively impacting national security, hygiene, and agriculture. Atmospheric water harvesting (AWH) is the conversion of ambient humidity into clean water; however, conventional dehumidification is energy-intensive. Improvement in AWH may be achieved with elastocaloric cooling, using temperature-sensitive materials in active thermoregulation. Potential benefits, compared to conventional desiccant wheel designs, include substantial reductions in energy use, size, and complexity. A nickel–titanium (NiTi) elastocaloric water harvester was designed and compared with a desiccant wheel design under controlled conditions of relative humidity, air volume, and power. In a 30 min interval, the NiTi device harvested more water on average at 0.18 ± 0.027 mL/WH, compared to the 0.1567 ± 0.023 mL/WH of the desiccant wheel harvester. Moreover, the NiTi harvester required half the power input and was thermoregulated more efficiently. Future work will focus on mechanical design parameter optimization. Elastocaloric cooling is a promising advancement in dehumidification, making AWH more economical and feasible. [ABSTRACT FROM AUTHOR]

The moisture content (MC) of wheat seeds must be reduced before storage using appropriate dehydration processes. Desiccant drying is a promising alternative to conventional drying methods because it improves seed quality while providing overall energy efficiency. This study explores the sorption drying of wheat seeds using granulated kieserite MgSO4·H2O as a solid desiccant, which has a high water capacity and is regenerated at low temperatures <100 °C. Desiccant characterization was conducted using SEM-EDS, XRD, DSC-TG, and particle size analysis. Wheat seeds mixed directly with kieserite in various mass ratios were dried under uniform stirring and controlled temperature conditions. A 240-min drying time was required to reduce the initial MC of wheat from 21.5% to 15.1% at a desiccant-to-grain ratio of 1:1. After 360 min, a final MC of 14.4% was achieved. The germination energy and seed capacity after sorption drying were 91 ± 1% and 97 ± 2%, respectively. Due to the available water capacity of kieserite, several batches of seeds can be dried without intermediate desiccant regeneration. This study is useful for developing low-cost, non-thermal, and sustainable drying technology for various agricultural products. [ABSTRACT FROM AUTHOR]

In this study, a numerical model of a modified air-drying process of apple slices that considers the conjugate heat and mass transfer in the drying chamber is developed. Inside the apple slice sample, the continuum model is incorporated to describe the non-isothermal two-phase transport. The intra- and extra-sample heat, mass, and momentum transfer are coupled to simulate the transportation phenomena inside the drying chamber using the finite volume method implemented in computational fluid dynamic software (COMSOL Multiphysics 6.0). In this manner, temperature, velocity, moisture content of the drying agent inside the chamber, sample temperature, and moisture content distributions can be predicted. The validity of the proposed model is confirmed by a good agreement between the numerical and experimental data in terms of the overall evaporation rate and temperature. The simulation results indicate that the maldistribution of the convective heat and mass transfer resistance on the sample surface is significant. This can be explained by the nonuniform velocity distribution inside the drying chamber. Additionally, both experimental and numerical observations show that the drying process can be divided into two periods: the quasi-constant drying rate and falling drying rate periods. The impact of dryer operational conditions on the drying process is numerically investigated. [ABSTRACT FROM AUTHOR]

This study investigates the development of protein powder from honey bee drone broods using foam-mat drying, a scalable method suitable for community enterprises, as well as the preservation of bee broods as a food ingredient. Initially, honey bee broods were pre-treated by boiling and steaming, with steamed bee brood (S_BB) showing the highest protein content (44.71 g/100 g dry basis). A factorial design optimized the powder formulation through the foam-mat drying process, incorporating varying concentrations of S_BB, glycerol monostearate (GMS), and carboxymethyl cellulose (CMC). The physicochemical properties of the resulting powder, including yield, color spaces, water activity, solubility, protein content, and total amino acids, were evaluated. The results showed that foam-mat drying produced a stable protein powder. The binders (CMC and GMS) increased the powder's yield and lightness but negatively affected the hue angle (yellow-brown), protein content, and amino acid content. The optimal quantities of the three variables (S_BB, GMS, and CMC) were determined to be 30 g, 6 g, and 1.5 g, or 80%, 16%, and 4%, respectively. Under this formulation, the protein powder exhibited a protein content of 19.89 g/100 g. This research highlights the potential of bee brood protein powder as a sustainable and nutritious alternative protein source, enhancing food diversification and security. [ABSTRACT FROM AUTHOR]

Drying food stuffs and other materials belongs to one of the most commonly used feedstock processing techniques, featuring rather high energy consumption. The major disadvantage of conventional electric convective-type household dryers is substantial thermal energy emission into the environment with a wet exhaust, worked-out drying agent. Among other principal disadvantages common to all dryers of this type, the following have to be mentioned: spatial inhomogeneity of heating a product under processing and that of drying agent distribution due to its temperature reduction and relative humidity growth as it moves upwards. A block diagram and a breadboard model of a convective-type thermoelectric dryer employing a thermoelectric heat pump have been designed. In our approach, a product is treated with the help of a drying agent (normally, heated air) with partial exhaust-air recirculation and heat recovery. Laboratory studies of the drying process have been carried out using apple fruits as a test material in order to evaluate the power consumed for evaporation of 1 kg of water in the newly developed convective-type thermoelectric drying unit. Physical parameters of apple fruits before and after drying both in the thermoelectric drying unit and in a conventional series-produced convective-type domestic dryer have been reported. The energy efficiency of the newly designed drying unit has been compared with that of some series-produced samples. It has been found out that, unlike conventional convective-type dryers, the breadboard model of the developed thermoelectric drying unit features a smoother product drying process owing to the presence of side air channels and more effective drying agent path organization in the processing chamber. This conclusion was supported by the results of the carried out tests. Application of thermoelectric heat pumps with the function of the exhaust drying agent heat recovery will make it possible to reduce the drying agent heater installed capacity and the power consumed by the newly designed convective-type thermoelectric drying unit by up to 20% in the course of the drying process, compared to series-produced household convective-type dryers. [ABSTRACT FROM AUTHOR]

The wettability and stability of a solution's film on the filler surface are the key factors determining heat and mass transfer efficiency in liquid desiccant air conditioning systems. Therefore, this study investigates the effects of different air parameters on the flow behavior of a lithium chloride solution's film. The effects of air velocity, air flow pattern, and pressure on the wettability and critical amount of spray are discussed. The results show that the main mechanism by which the air velocity affects the wettability is that the shear stress generated by the direction of the air velocity disperses the direction of the surface tension and weakens its effect on the liquid film distribution. In addition, in the counter flow pattern, the air flow blocks the liquid film from spreading longitudinally and destroys the stability of the liquid film at the liquid outlet, which increases the critical amount of spray. The pressure distribution is similar under different operating pressures when the flow is stable; thus, pressure has little effect on wettability. The simulation results under 8 atm are compared with the experimental results. It is found that the sudden increase in the amount of moisture removal when the amount of spray changes from 0.05 to 0.1 m3/(m·h) in the experiment is caused by the change in the liquid film flow state. In addition, the results show that within the range of air flow parameters for the liquid desiccant air conditioning system, air flow shear force is not the main factor affecting the stability of the solution's film, and there is no secondary breakage of the solution's film during the falling-film flow process. [ABSTRACT FROM AUTHOR]

The efficiency of household dehumidifiers is affected by air temperature and the temperature used for regeneration. A regeneration temperature that is too high can lead to increased energy use, heat build-up in the desiccant wheel, and lower dehumidification efficiency. In this study, we developed a LiCl@Al-Fum composite material and evaluated it through physical characterization and module testing. The results show that the LiCl@Al-Fum composite with a 20% mass fraction is particularly effective as a desiccant material. Additionally, a 15% volume concentration of neutral silica sol was identified as the optimal binder concentration. A comparative analysis of the effects of glass-fiber desiccant wheels (GF DWs), aluminum desiccant wheels (Al DWs), and commercial desiccant wheels (CM DWs) on household dehumidifier performance revealed that the Al DWs outperformed the CM DWs, showing a 13% improvement in the dehumidification rate and a 12.56% increase in the DCPP. An increase in the dehumidifier structure led to increases in the dehumidification rate by 11.8%, 11.9%, and 10% and in the DCPP by 11.6%, 12.1%, and 10%, respectively. Moreover, the modifications resulted in a 3.85 °C, 3.34 °C, and 3.8 °C decrease in the temperature. [ABSTRACT FROM AUTHOR]

The reaction of glycerol with CO2 to produce glycerol carbonate was performed successfully in the presence of gold nanoparticles (AuNPs) supported by a metal–organic framework (MOF) constructed from mixed carboxylate (terephthalic acid and 1,3,5-benzenetricarboxylic acid). The most efficient were two AuNPs@MOF catalysts prepared from pre-synthesized MOF impregnated with Au3+ salt and subsequently reduced to AuNPs using H2 (catalyst 4%Au(H2)@MOF1) or reduced with NaBH4 (catalyst 4%Au@PEI-MOF1). Compared to existing catalysts, AuNPs@MOFs require simple preparation and operate under mild and sustainable conditions, i.e., a much lower temperature and the lowest CO2 overpressure ever reported, with MgCO3 having been found to be the optimal dehydrating agent. Although the yield of the process is still not competitive with previously developed systems, the most promising advantage is the highest TOF (78 h−1) ever reported for this reaction. The optimal parameters observed for AuNPs were also tested on AgNPs and CuNPs with promising results, suggesting their great potential for industrial application. The catalysts were characterized by XRD, TEM, SEM-EDS, ICP-MS, XPS, and porosity measurements, confirming that AuNPs are present in low concentration, uniformly distributed, and confined to the cavities of the MOF. [ABSTRACT FROM AUTHOR]

Lavender distillation produces huge quantities of solid waste yearly. This waste is usually discarded, resulting in serious environmental issues. However, it still contains residual essential oil and other bioactive compounds. This research reports on the development and comparison of optimized solid–liquid separation methods, i.e., microwave- (MAE) and ultrasound-assisted extraction (UAE) of phenolic compounds from lavender distillation waste. The optimal pretreatment conditions, such as waste moisture content and particle size, were also determined. The extracts were spray- or freeze-dried and the resulting powders were characterized for their physicochemical properties. The majority of the original phenolic compounds in lavender were found in the leachate fraction after distillation (61%), whereas 43% was found in the solid waste. Drying of the solid waste before extraction affected the process efficiency. UAE led to a higher phenolic content and greater antioxidant properties compared to MAE. Drying (spray or freeze) the extracts did not significantly affect their phenolic content, whereas the use of maltodextrin as a drying agent improved the drying process yield, especially when using the freeze-drying method. It is concluded that valorization of lavender distillation wastes can be achieved via an integrated process consisting of a green extraction method and a consequent drying process that results in a stable bioactive powder. [ABSTRACT FROM AUTHOR]

Heated Tobacco Products (HTPs) purport to reduce exposure to tobacco-related toxicants compared to combustible cigarettes. This cross-sectional study examined the content of nicotine, two humectants (propylene glycol (PG) and vegetable glycerin (VG)), and four tobacco-specific nitrosamines (TSNAs: NNN, NNK, NAT, and NAB) in the tobacco filler of a popular HTP brand (IQOS). Non-menthol and menthol IQOS sticks were purchased from nine countries between 2017 and 2020 and were classified into two versions ("Bold" and "Light") using Philip Morris's flavor descriptors. The average nicotine concentration was 4.7 ± 0.5 mg/stick, and the highest nicotine concentration was found in products from Japan (5.1 ± 0.2 mg/stick). VG was the dominant humectant found in all sticks, with an average concentration of (31.5 ± 2.3 mg/stick). NNN, NNK, and NAT were substantially higher in the "Bold" sticks than the "Light" sticks. Significant differences between countries for TSNAs were also observed: the NAT and NAB contents were the highest in the "Light" products from Canada (192.5 ± 24.1 and 22.9 ± 1.0 ng/stick, respectively); the NNK concentration was the highest in the "Bold" products from Poland (64.8 ± 7.9 ng/stick); and the highest NNN concentrations were observed in the "Bold" products from South Africa (488.9 ± 26.7 ng/stick). As NNN and NNK are known human carcinogens, and as humectants like PG and VG can degrade into toxic carbonyl compounds upon heating, monitoring the concentration of these chemicals in HTPs is important for protecting users' health and ensuring compliance with regulations. [ABSTRACT FROM AUTHOR]

The direct synthesis of dimethyl carbonate (DMC) from methanol and CO2 presents an attractive route to turn abundant CO2 into value-added chemicals. However, insufficient DMC yields arise due to the inert nature of CO2 and the limitations of reaction equilibrium. Oxygen vacancies are known to facilitate CO2 activation and improve catalytic performance. In this work, we have demonstrated that tuning oxygen vacancies in catalysts and implementing in situ water removal can enable highly efficient DMC production from CO2. CexZryO2 nanorods with abundant oxygen vacancies were synthesized via a hydrothermal method. In liquid-phase DMC synthesis, the Ce10Zr1O2 nanorods exhibited a 1.7- and 1.4-times higher DMC yield compared to CeO2 nanoparticles and undoped CeO2 nanorods, respectively. Zr doping yielded a CeZr solid solution with increased oxygen vacancies, promoting CO2 adsorption and activation. In addition, adding 2-cyanopyridine as an organic dehydrating agent achieved an outstanding 87% methanol conversion and >99% DMC selectivity by shifting the reaction equilibrium to the desired product. Moreover, mixing CeO2 nanoparticles with hydrophobic fumed SiO2 in gas-phase DMC synthesis led to a doubling of DMC yield. This significant increase was attributed to the faster diffusion of water molecules away from the catalyst surface, facilitated by the hydrophobic SiO2. This study illustrates an effective dual strategy of enhancing oxygen vacancies and implementing in situ water removal to boost DMC production from CO2. The strategy can also be applied to other reactions impacted by water accumulation. [ABSTRACT FROM AUTHOR]

Adsorptive atmospheric water harvesting systems (AWHs) represent an innovative approach to collecting freshwater resources from the atmosphere, with a hygroscopic agent at their core. This method has garnered significant attention due to its broad applicability, strong recycling capacity, and sustainability. It is being positioned as a key technology to address global freshwater scarcity. The core agent's hygroscopic properties play a crucial role in determining the performance of the AWHs. This article provides a comprehensive review of the latest advancements in hygroscopic agents, including their adsorption mechanisms and classifications. This study of hygroscopic agents analyzes the performance and characteristics of relevant porous material composite polymer composites and plant composites. It also evaluates the design and preparation of these materials. Aiming at the problems of low moisture adsorption and desorption difficulty of the hygroscopic agent, the factors affecting the water vapor adsorption performance and the method of enhancing the hygroscopic performance of the material are summarized and put forward. For the effect of hygroscopic agents on the volume of water catchment devices, the difference in density before and after hygroscopicity is proposed as part of the evaluation criteria. Moisture absorption per unit volume is added as a performance evaluation criterion to assess the effect of hygroscopic agents on the volume of water collection equipment. The article identifies areas that require further research and development for moisture absorbers, exploring their potential applications in other fields and anticipating the future development direction and opportunities of moisture-absorbing materials. The goal is to promote the early realization of adsorptive atmospheric water harvesting technology for large-scale industrial applications. [ABSTRACT FROM AUTHOR]

In order to withstand high-temperature environments, ultra-high molecular weight polyethylene (UHMWPE) fibers with cooling properties are being increasingly used in personal thermal management textiles during the summer. However, there is relatively little research on its combination with knitting. In this paper, we combine UHMWPE fiber and knitting structure to investigate the impact of varying UHMWPE fiber content and different knitting structures on the heat and humidity comfort as well as the cooling properties of fabrics. For this purpose, five kinds of different proportions of UHMWPE and polyamide yarn preparation, as well as five kinds of knitted tissue structures based on woven tissue were designed to weave 25 knitted fabrics. The air permeability, moisture permeability, moisture absorption and humidity conduction, thermal property, and contact cool feeling property of the fabrics were tested. Then, orthogonal analysis and correlation analysis were used to statistically evaluate the properties of the fabrics statistically. The results show that as the UHMWPE content increases, the air permeability, heat conductivity, and contact cool feeling property of the fabrics improve. The moisture permeability, moisture absorption and humidity conductivity of fabrics containing UHMWPE are superior to those containing only polyamide. The air permeability, moisture permeability, and thermal conductivity of the fabrics formed by the tuck plating organization are superior to those of the flat needle plating and float wire plating organization. The fabric formed by 2 separate 2 float wire organization has the best moisture absorption, humidity conduction, contact cool feeling property. [ABSTRACT FROM AUTHOR]

Background and Objectives: The rise in suicidal attempts has led to an increase in unusual intoxication cases. The ingestion of anhydrous calcium chloride (CaCl2) causes direct injury to the gastrointestinal wall via a thermal burn. Therefore, previous reports on CaCl2 ingestion primarily considered the gastrointestinal injury. Severe CaCl2 intoxication can induce a hypercalcemic crisis, presenting with arrhythmia, acute pancreatitis, and acute kidney injury. This case report details a patient with hematemesis and hypercalcemia following the ingestion of a commercial desiccant. We aimed to report the progression of the case, with a focus on the electrocardiographic manifestations. Case Presentation: A 39-year-old female presented at a regional emergency center with blood in her vomit after the ingestion of a commercial desiccant. Bloody emesis was the initial symptom, and various electrolyte imbalances developed during admission. Electrocardiogram (ECG) changes occurred early after hospitalization and disappeared before the electrolyte levels normalized. The patient was maintained in an NPO (Nil Per Os) state throughout her hospital stay. The bloody emesis and abdominal pain resolved quite early, despite her minimal mention of symptoms, possibly due to her suspected negative psychiatric symptoms. Conclusions: In this case, we observed dynamic and prolonged multiple electrolyte imbalances along with the early-phase ECG changes, all of which responded well to supportive care. This report adds to the understanding of the diverse manifestations and management of CaCl2 intoxication. [ABSTRACT FROM AUTHOR]

Seed treatment is a powerful technique for adding beneficial ingredients to plants during the seed preparation process. Biopolymers as drying agents and delivery systems in seed treatments were investigated for their biocompatibility with blastospores of the nematophagous fungus Pochonia chlamydosporia. To produce a novel seed treatment for the cover crop Phacelia tanacetifolia, xanthan gum TG and gellan gum were the most promising biopolymers in combination with potato starch and bentonite. The seed treatment process as well as the drying process were specially designed to be scalable, which make it suitable for applying the developed seed treatment in agriculture. Application of gellan gum in seed treatments led to 6.3% ± 1.6% of vital blastospores per seed compared to 3.8% ± 0.3% of vital blastospores when applying xanthan gum. Storage tests for seed treatments with 0.5% gellan gum indicated a higher stability at 4 °C compared to storage at 21 °C. After 42 days of storage at 4 °C, 54.1% ± 15.1% of the applied blastospores were viable compared to 0.3% ± 0.8% at 21 °C. This novel seed treatment application with P. chlamydosporia blastospores includes the seed treatment procedure, drying process, and storage tests and can easily be upscaled for application in agriculture. [ABSTRACT FROM AUTHOR]

Much scientific equipment requires the use of humidity control technologies. This includes instruments with hygroscopic optics, such as infrared spectrometers, OPOs and some lasers. The most common strategies include nitrogen purging or desiccant bag replacement, which involve maintenance and running costs. In this work we present a dual strategy, combining both ionic membranes and silica desiccant, which results in a reusable and maintenance-free scheme for humidity control. The desiccant action of the silica gels, the membrane, and combinations thereafter, are studied. It is shown that the combination of the silica gel desiccants and the membrane is the most efficient configuration, reducing the humidity from 73% to only 15% in 20 h in a 70 L volume and from 80% to 20% in 40 h in a 230 L volume. An experiment over 5 days showed that the status of the silica gel desiccants that had adsorbed high water vapor levels returned to normal after they were enclosed together with the ionic membrane in the 70 L volume. Finally, measurements taken by a commercial infrared spectrometer of the reduction in the H2O lines absorption in the mid-infrared region under the operation of the combined configuration are examined. It was demonstrated that H2O lines with low to moderate absorption almost disappeared when the humidity levels inside the spectrometer dropped from 42.5% to 15.1% in the span of 90 min, while lines with stronger absorption remained present even though they showed the highest percentage of change. [ABSTRACT FROM AUTHOR]

The water sorption and desorption properties of solid adsorbent materials are crucial in rotary dehumidification systems. Metal organic frameworks (MOFs) and hydrogels are mostly at the laboratory stage due to factors like the synthesis process and yield. In this study, we utilized an eco-friendly and large-scale synthesis method to prepare polyacrylamide (PAM) hydrogels (yielding approximately 500 mL from a single polymerization). Subsequently, PAM was then coated onto glass fiber paper (GFP), which serves as a commonly employed substrate in desiccant wheels. By incorporating the hygroscopic salt LiCl and optimizing the content of each component, the water sorption performance of the composite was notably improved. The water sorption and desorption performances, as well as cycling stability, were evaluated and compared with composites containing aluminum fumarate, LiCl, and GFP (AlFum-LiCl&GFP). The results revealed that PAM-LiCl&GFP outperformed AlFum-LiCl&GFP in terms of sorption capacity throughout various relative humidity (RH) levels. It achieved a water uptake of 1.06 g·g−1 at 25 °C and 30% RH, corresponding to a water sorption rate coefficient K of 15.32 × 10−4 s−1. Furthermore, the lower desorption temperature (60 °C) resulting in a desorption ratio of 82.6%, along with the excellent cycling stability and effective performance as a desiccant wheel module, provide evidence for the potential application of PAM-LiCl&GFP in desiccant wheels. [ABSTRACT FROM AUTHOR]

This paper presents the effect of drying control agents on the physicochemical and thermal properties of hydrophobic silica aerogels derived via the ambient pressure drying (APD) method by a surface silylation using a TMCS/n-hexane mixture. The structural and physicochemical properties of synthesized DMF-modified and unmodified hydrophobic silica aerogels were characterized using Brunauer–Emmett–Teller (BET) analysis, thermo-gravimetric analysis, FT-IR, and Raman spectroscopic techniques. Based on the obtained results, the differences in structure between samples before and after a surface silylation and the effect of drying control agents were documented. The structural measurements confirmed the efficient silylation process (TMCS/n-hexane), as well as the presence of DMF residues of hydrogen bonded with unreacted Si-OH silanol groups within the silica backbone after surface modification. Based on TG analysis, it was found that DMF addition improves thermal resistance (up to 320 °C) and hydrophobic character of prepared aerogel. Modification of the silica aerogel synthesis process by DMF also resulted in a significant increase in BET—the specific surface area, for the unmodified aerogel was ~828 m2/g, and for the DMF-modified aerogel more than 1200 m2/g—much higher than the value of silica aerogels available on the market. [ABSTRACT FROM AUTHOR]

This study investigates the mycelial biomass production and chitosan extraction potential of various Basidiomycota strains, including Heterobasidion annosum, Phanerochaete chrysosporium, Pleurotus ostreatus, Trametes versicolor, and Lentinus lepideus. Both submerged fermentation (SF) and solid-state fermentation (SSF) methods were employed. The chitosan yield in basidiocarps of Pleurotus ostreatus, Agaricus bisporus, and Ganoderma applanatum was also evaluated as a reference material. The chitosan extracted from fungal cells was characterized using elemental analyses and FTIR spectroscopy. Among the cultivated strains, P. chrysosporium exhibited the highest mycelial biomass concentration in SF (1.03 g 100 mL–1) after 14 days, while T. versicolor achieved the highest biomass concentration in SSF (3.65 g 100 mL–1). The highest chitosan yield was obtained from the mycelium of P. chrysosporium (0.38%) and T. versicolor (0.37%) in shaken SF. Additionally, commercially cultivated A. bisporus demonstrated the highest chitosan yield in fungal fruiting bodies (1.7%). The extracted chitosan holds potential as a functional biopolymer additive for eco-friendly materials, serving as an alternative to synthetic wet and dry strength agents in packaging materials. [ABSTRACT FROM AUTHOR]

There has been considerable research worldwide on desiccant-based air-conditioning during the past 30 years. The rationale for the push for this new research focus has been twofold: (a) the need to provide an alternative to conventional refrigerative air-conditioning systems which rely heavily on fossil fuels as their energy sources, and (b) the need to provide better thermal comfort in air-conditioned spaces in warm to hot and humid climates. A desiccant air-conditioning system consists of several components to cool and dehumidify the air before it is supplied to a conditioned space. Earlier research work has identified the potential advantages of this technology, which include the following: (1) working fluids that do not impact on the ozone layer, (2) reduced electricity consumption, (3) improved indoor air quality, (4) simpler construction and less maintenance, and (5) integral provision of heating and cooling for cold/temperate climates. On the other hand, the authors of this paper identified the following drawbacks: (1) inevitable heating of air while being dehumidified, (2) the need for desiccant regeneration and low thermal COP paradox, (3) limited options for regeneration heat sources, (4) limited options for reliable cooling, and (5) low electrical coefficient of performance (COP). This paper presents a critical review of the energy and thermal comfort performance of solid-desiccant rotor-based air-conditioning systems, and discusses in detail their potential advantages and drawbacks. This critical review found that the drawbacks of the systems outweigh their identified advantages. The main reason for this is the inevitable heating of air while being dehumidified and counterintuitive addition of moisture to air during the evaporative cooling process. During the past 30 years of research and development efforts, no significant innovations have been discovered to resolve these crucial issues. Unless future research and development is directed to find a breakthrough, this technology will have limited commercial application. [ABSTRACT FROM AUTHOR]

Herbicides with desiccant actions may be used to anticipate the harvesting of soybean seeds. This technique aims to minimize the negative influence of biotic and abiotic factors on seed physiological quality at the end of the plant cycle. However, forced seed maturation with the application of herbicides can compromise the acquisition of seed quality components, especially longevity. Thus, the objective of this research was to evaluate the physiological quality of soybean seeds subjected to forced maturation with desiccants. The experiment was performed in a completely randomized design, with a treatment consisting of soybean plants subjected to the application of herbicides with desiccant action at stage R7.3 and another that underwent the natural process of maturation, that is, without herbicide application. The herbicide used was Paraquat. Seed germination, vigor (first germination count, dry mass, seedling length, time to reach 50% germination(t50), emergence index, and emergence speed), and longevity(P50) were evaluated. The herbicides did not affect germination (normal seedlings). However, the acquisition of vigor and longevity, and the preservation of seed vigor during storage were affected. Thus, the results indicate that the application of herbicide with desiccant action interrupts the process of acquisition of seed physiological quality, notably longevity in soybean seeds. [ABSTRACT FROM AUTHOR]

Dehumidifying air via refrigerant cooling method consumes a tremendous amount of energy. Independent humidity control systems using desiccants have been introduced to improve energy efficiency. This research aimed to find an alternative to the commonly used solid desiccant, silica gel, which has weak physical adsorption properties. It also aimed to overcome the limitation of liquid desiccants that may affect indoor air quality and cause corrosion. This study reports on the synthesis of poly(vinyl alcohol-co-acrylic acid), P(VA-AA), through solution polymerisation by hydrolysing poly(vinyl acetate-co-acrylic acid), P(VAc-AA). This viable copolymer was then incorporated with graphene oxide (GO) at different concentrations (0 wt.%, 0.5 wt.%, 2 wt.% and 5 wt.%) to enhance the adsorption–desorption process. The samples were tested for their ability to adsorb moisture at different levels of relative humidity (RH) and their capability to maintain optimum sorption capacity over 10 repeated cycles. The nanocomposite film with 2% GO, P(VA-AA)/GO2, exhibited the highest moisture sorption capacity of 0.2449 g/g for 60–90% RH at 298.15 K, compared to its pristine copolymer, which could only adsorb 0.0150 g/g moisture. The nanocomposite desiccant demonstrated stable cycling stability and superior desorption in the temperature range of 318.15–338.15 K, with up to 88% moisture desorption. [ABSTRACT FROM AUTHOR]

Air-conditioning systems account for 40–60% of the energy consumption of buildings, and most of this figure corresponds to the cooling and dehumidification process of air-conditioning units. Compared with traditional compressed air-conditioning systems, solid adsorption dehumidification systems possess good potential to improve indoor air quality and reduce buildings' energy consumption. However, there are still some problems that prevent the use of solid adsorption dehumidification systems, such as their complexity and high regeneration temperatures. The key to solving the above problem is the discovery of more suitable adsorbents. In this paper, poly N-isopropylacrylamide/polypyrrole (PNIPAm/PPy) hydrogel was selected as the research object, and the performance of the dehumidification material and its potential for application in solid dehumidification systems were studied. It was found that the pore structure of PNIPAm/PPy was relatively complex and that there were abundant pores with uneven pore sizes. The minimum pore size was about 4 μm, while the maximum pore size was about 25 μm, and the pore sizes were mostly distributed between 8 and 20 μm. Abundant and dense pores ensure good hygroscopic and water-releasing properties of the resulting hydrogel. The PPy inside the hydrogel acts as both a hygroscopic and photothermal agent. In an environment with a relative humidity of 90%, 60%, and 50%, the hygroscopic efficiency of PNIPAm/PPy reached 80% in about 75, 100, and 120 min, and the corresponding unit equilibrium hygroscopic capacity values were 3.85 g/g, 3.72 g/g, and 3.71 g/g, respectively. In the initial stage, the moisture absorption increased with the increase in time; then, the increase in moisture absorption decreased. When the temperature was below 40 °C, the hygroscopic performance of PNIPAm/PPy was almost temperature-independent. The PNIPAm/PPy with different thicknesses showed similar moisture absorption efficiency. The lowest desorption temperature of PNIPAm/PPy was 40 °C, which indicates that low-grade energy can be used for material desorption. And the higher the temperature, the faster the desorption rate of PNIPAm/PPy and the higher the desorption amount. It can be seen that the PNIPAm/PPy hydrogel presents good desorption performance and can be used repeatedly. [ABSTRACT FROM AUTHOR]

This randomized, split-mouth, controlled clinical study assessed the additional clinical benefits of a local desiccant antimicrobial agent (HY) combined with subgingival mechanical instrumentation (SRP) vs. SRP alone in treating severe periodontitis. Patients with stages III and IV periodontitis received full-mouth periodontal examinations at baseline and after a three-month follow-up. Two randomly selected hemiarches in each periodontitis patient were treated with SRP plus HY and were included in the test group, while the other two hemiarches received only SRP and were included in the control group. In thirty patients, the analyses of the evolution of the periodontal parameters over time showed statistically significant mean differences for the probing depths and clinical attachment level values resulting from all the examined sites, as well as from the interproximal sites (p < 0.001) in both the test and control groups. The intergroup comparisons of the same four parameters showed no significant differences (p = 0.322, p = 0.36, p = 0.516, and p = 0.509, respectively). Based on these study results, no additional benefits were obtained after HY subgingival applications. [ABSTRACT FROM AUTHOR]

In order to determine the water vapor adsorption performance of a rotary desiccant-based air conditioning system, the behavior of water adsorption on cylindrical pores of different sizes was studied by using classical density functional theory (CDFT) based on perturbated chain statistical associating fluid theory (PC-SAFT). Firstly, the structural parameters of the desiccant material were characterized by scanning electron microscopy (SEM), X-ray Energy Dispersive Spectrum (EDS), and N2 adsorption/desorption isotherms, as well as adsorption equilibrium measurements of water vapor at temperature range 293–308 K. Secondly, the potential energy equation of water molecules in cylindrical pores was determined, and contribution of various terms of PC-SAFT for simulating fluid in cylindrical pores were established. Finally, the pore size distribution (PSD) of the desiccant materials is determined by the PC-SAFT kernel. Moreover, water vapor condensation was investigated with the PC-SAFT model in micropores. The results indicate that the rotary desiccant materials have a large number of micropores with a volume of 0.3669 cm3/g and the amount of water adsorption is about 0.285 g/g. The condensation pressure and the pore width corresponding to the saturated pressure P0 grow with an increase in the temperature, signifying that adjusting the PSD of the material has a significant effect on improving the dehumidification performance. The research concludes that the PSD range of the oxide cylindrical pore between 1.09 and 1.53 nm is particularly beneficial for dehumidification. This study provides valuable theoretical guidance for optimizing dehumidification materials. [ABSTRACT FROM AUTHOR]

The study examined the effects of pulsed electric field treatment on the kinetics and properties of convective-dried mushrooms using different drying agents. Increasing the drying air temperature reduced drying time, while the use of dehumidified air resulted in faster water removal. PEF treatment, depending on the parameters, shortened the drying time maximum by 12% or extended the drying time. The physical (dry matter content, rehydration properties, hygroscopic properties, and color) and chemical (polyphenols content and anti-oxidant activity) properties were analyzed. The dry matter contents of the mushrooms were influenced by the drying temperature, while PEF pre-treatment did not influence the rehydration and hygroscopic properties in both cases of drying using air humidity. However, the color parameters were affected by the drying method and energy input, with higher energy input leading to decreased lightness, increased redness, and color saturation. The chemical analyses revealed that the anti-oxidant compounds in the dried mushrooms were influenced by various factors, with PEF treatment and drying non-dehumidified air polyphenol content increasing, whereas dehumidified air caused more phenolic degradation if it was combined with PEF treatment. Anti-oxidant activity varied depending on the drying agent, with non-dehumidified air generally exhibiting better properties. The highest total polyphenol content and best anti-oxidant properties were obtained for the PEF pre-treated with 3 kJ/kg of energy and dried with non-dehumidified air at a temperature of 70 °C. [ABSTRACT FROM AUTHOR]

A review of desiccant dehumidification technologies for improving air quality is presented, mainly focusing on alternatives for air conditioning systems for minimizing Sick Building Syndrome. The principles and types of desiccant wheels, as well as the existing selection software for these types of equipment, were reviewed and comparatively evaluated. The study focused on the Brazilian context; thus, information about this country's air conditioning systems and laws were evaluated. Possible applications of desiccant wheels, such as their integration into cooling cycles and the sensible heat wheel, were also analyzed. Finally, several examples of commercial desiccant wheel selection software that are useful in many situations were evaluated. Nevertheless, it was evidenced that the available software could not perform an operation analysis for only a specific period. Therefore, creating computational tools to select desiccant wheels is essential when considering the data from the different Brazilian regions for a year. [ABSTRACT FROM AUTHOR]

This study discusses the choice of dehumidification systems for high-moisture indoor environments, such as indoor swimming pools, supported by an eco-energetic performance comparison. Initially, the causes of the high relative humidity and condensation in these spaces are reported, as well as the available dehumidification technologies. Two different solutions are described: desiccant wheel dehumidification and re-cooling. The energy demand required by a refrigeration system is lower than the desiccant wheel; however, the former system requires less maintenance and does not require refrigerant fluid. An eco-energetic comparison is performed between the two systems in two countries with different energy matrices (Brazil and USA). In Brazil, the desiccant wheel is the best choice for the past 10 years, with a predicted 351,520 kgCO2 of CO2 emissions, which is 38% lower than the refrigeration system. In the USA, the best option is the refrigeration system (1,463,350 kgCO2), a 12% more efficient option than desiccant wheels. This model can be considered for energy and CO2 emissions assessment, predicting which system has better energy efficiency and lower environmental impact, depending on the refrigerant type, location and environmental conditions. [ABSTRACT FROM AUTHOR]

Indoor comfort has become a major factor with advancements in science and technology. This also leads to an increase in greenhouse gases as well as energy consumption. Desiccant-coated heat exchangers are one of the common solutions to these risks and to lower energy usage. In the present work, the capability of a solid composite desiccant blend prepared from coconut shell-based activated carbon and bio char was studied. Aluminum plates have been coated with the prepared solid desiccants. Desiccant-coated heat exchangers were cooled by the cerium oxide nanofluid passing through the pipes connected along the length of the heat exchanger. Air was blown through the plates where dehumidification occurs due to the vapor pressure difference between the air and the desiccant-coated plate. The experiments were conducted by varying the air velocity, water flow rate, and nanoparticle concentration. The nanoparticle volume fraction varied from 0.05% to 0.3%. Different performance parameters such as the moisture removal rate, dehumidification efficiency, cooling capacity, and coefficient of performance (COP) were calculated. Results showed that the performance parameters were enhanced with an increase in the water flow rate as well as the air flow rate. Furthermore, it was seen that with the addition and increase in nanoparticle concentration, the moisture removal rate and dehumidification efficiency were enhanced. In comparison to no addition of nanoparticles, a 0.3% addition of nanoparticles demonstrated a maximum increase in MRR of 53% and dehumidification efficiency of 57%. A maximum reduction of 6.1% in the dehumidification area was achieved by using 0.3% nanoparticles with water. It is recommended to use nanofluids for dehumidification using solid desiccants, which can enhance the performance without having negative influence on the environment. [ABSTRACT FROM AUTHOR]

Human rotavirus (HRV) is the causative agent of severe dehydrating diarrhea in children under the age of five, resulting in up to 215,000 deaths each year. These deaths almost exclusively occur in low- and middle-income countries where vaccine efficacy is the lowest due to chronic malnutrition, gut dysbiosis, and concurrent enteric viral infection. Parenteral vaccines for HRV are particularly attractive as they avoid many of the concerns associated with currently used live oral vaccines. In this study, a two-dose intramuscular (IM) regimen of the trivalent, nanoparticle-based, nonreplicating HRV vaccine (trivalent S60-VP8*), utilizing the shell (S) domain of the capsid of norovirus as an HRV VP8* antigen display platform, was evaluated for immunogenicity and protective efficacy against P[6] and P[8] HRV using gnotobiotic pig models. A prime–boost strategy using one dose of the oral Rotarix® vaccine, followed by one dose of the IM trivalent nanoparticle vaccine was also evaluated. Both regimens were highly immunogenic in inducing serum virus neutralizing, IgG, and IgA antibodies. The two vaccine regimens failed to confer significant protection against diarrhea; however, the prime–boost regimen significantly shortened the duration of virus shedding in pigs challenged orally with the virulent Wa (G1P[8]) HRV and significantly shortened the mean duration of virus shedding, mean peak titer, and area under the curve of virus shedding after challenge with Arg (G4P[6]) HRV. Prime–boost-vaccinated pigs challenged with P[8] HRV had significantly higher P[8]-specific IgG antibody-secreting cells (ASCs) in the spleen post-challenge. Prime–boost-vaccinated pigs challenged with P[6] HRV had significantly higher numbers of P[6]- and P[8]-specific IgG ASCs in the ileum, as well as significantly higher numbers of P[8]-specific IgA ASCs in the spleen post-challenge. These results suggest the promise of and warrant further investigation into the oral priming and parenteral boosting strategy for future HRV vaccines. [ABSTRACT FROM AUTHOR]

Unconventional polysaccharides as representative active substances from stems of Trollius chinensis Bunge (TC) were studied. Crude polysaccharides from the stems of TC (TCSP) and the petals of TC (TCPP) were extracted, and the moisture retention and antioxidation activities of both TCSP and TCPP in vitro were studied. The weight-average molar masses (Mw) of TCSP (6.07 × 105 Da) were lower than those of TCPP (9.72 × 105 Da). Glucuronic acid and xylose only existed in TCSP, and the molar ratio of galacturonic acid and mannose in TCSP was significantly higher than that in TCPP. No significant differences in moisture retention ability were found between TCSP and TCPP. The reducing capacity and dphenyl picryl hydrazinyl (DPPH) radical scavenging capacity of TCSP were slightly weaker than those of TCPP. The 2,2-azino-bis (3-ethylbenzothiazoline–6-sulfonic acid) (ABTS) radical scavenging capacity of TCSP can be equivalent to that of TCPP. The moisture retention ability was not different between TCSP and TCPP, which are both highly homologous with traditional humectants. The antioxidation assays in vitro demonstrated that the antioxidant activity of TCSP is stronger compared to that of some plant-derived polysaccharides. The stems of TC can be a promising source of unconventional polysaccharides, which possess moisture retention and antioxidation capacities for the cosmetics industry. [ABSTRACT FROM AUTHOR]

After being harvested, fresh apples and apricots have a high moisture content and are put through a drying process to reduce waste and lengthen shelf life. This study intends to evaluate the physicochemical parameters during moisture removal and product heating in order to conduct an experimental investigation of the convective drying of apples and apricots in a pilot drying installation. The drying agent's temperature and/or speed can be adjusted using the pilot installation. About the raw materials: the apricots (Neptun variety) were dried and cut into halves, while the apples (Golden Delicious variety) were dried and cut into 4 mm thick slices. The fruits' drying properties were observed at 50 °C, 60 °C, 70 °C, and 80 °C, air speeds of 1.0, 1.5, and 2.0 m/s, and relative air humidity levels of 40–45%. Findings of the ascorbic acid content, color, heating, and dimensional fluctuations are provided and examined. Increased air velocity and temperature had the expected effect of increasing water loss, solid gain, and shrinking. Depending on the drying conditions, different color characteristics were applied. [ABSTRACT FROM AUTHOR]

Catalytic conversion of CO2 with the surplus glycerol (GL) produced from biodiesel manufacturing has attracted much academic and industrial attention, which proves the urgent requirement for developing high-performance catalysts to afford significant environmental benefits. Herein, titanosilicate ETS-10 zeolite-based catalysts with active metal species introduced by impregnation were employed for coupling CO2 with GL to efficiently synthesize glycerol carbonate (GC). The catalytic GL conversion at 170 °C miraculously reached 35.0% and a 12.7% yield of GC was obtained on Co/ETS-10 with CH3CN as a dehydrating agent. For comparison, Zn/ETS- Cu/ETS-10, Ni/ETS-10, Zr/ETS-10, Ce/ETS-10, and Fe/ETS-10 were also prepared, which showed inferior coordination between GL conversion and GC selectivity. Comprehensive analysis revealed that the presence of moderate basic sites for CO2 adsorption-activation played a crucial role in regulating catalytic activity. Moreover, the appropriate interaction between cobalt species and ETS-10 zeolite was also of great significance for improving the glycerol activation capacity. A plausible mechanism was proposed for the synthesis of GC from GL and CO2 in the presence of CH3CN solvent over Co/ETS-10 catalyst. Moreover, the recyclability of Co/ETS-10 was also measured and it proved to be recycled at least eight times with less than 3% decline in GL conversion and GC yield after a simple regeneration process through calcination at 450 °C for 5 h in air. [ABSTRACT FROM AUTHOR]

Periodontitis is one of the most common oral polymicrobial infectious diseases induced by the complex interplay between the altered subgingival microbiota and the host's dysregulated immune-inflammatory response, leading to the initiation of progressive and irreversible destruction of the periodontal tissues and eventually to tooth loss. The main goal of cause-related periodontal therapy is to eliminate the dysbiotic subgingival biofilm in order to arrest local inflammation and further periodontal tissue breakdown. Because, in some cases, subgingival mechanical instrumentation has limited efficiency in achieving those goals, various adjunctive therapies, mainly systemic and locally delivered antimicrobials, have been proposed to augment its effectiveness. However, most adjunctive antimicrobials carry side effects; therefore, their administration should be precociously considered. HybenX® (HY) is a commercial therapeutical agent with decontamination properties, which has been studied for its effects in treating various oral pathological conditions, including periodontitis. This review covers the current evidence regarding the treatment outcomes and limitations of conventional periodontal therapies and provides information based on the available experimental and clinical studies related to the HY mechanism of action and effects following its use associated with subgingival instrumentation and other types of dental treatments. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the feasibility of the single-effect H2O/LiBr absorption heat pump cycle to produce combined heating and cooling. To achieve this, first, the main changes that the absorption cycle requires are described in comparison with the conventional single-effect absorption chiller. Then, the cycle's operational limits in terms of temperature lift and LiBr crystallization are evaluated. In this sense, driving heat temperatures required for these applications range from 85 °C to 120 °C. The energy and exergy performance (in terms of cooling and heating capacities, cooling and heating coefficient of performance, and exergy coefficient of performance) of the cycle is theoretically studied for five different types of applications that require simultaneous heating and cooling: building air conditioning, a 4th generation district heating and cooling network, a sports center with an indoor swimming pool, a hybrid air conditioning system with an absorption heat pump and a desiccant evaporative cooling system, and simultaneous cooling and water purification application for coastal areas. The system performance in terms of the cooling coefficient of performance varies in the range of 0.812–0.842, in terms of heating coefficient of performance from 0.58 to 1.842, and in terms of exergy coefficient of performance from 0.451 to 0.667. The application with the highest exergy coefficient of performance is the 4th generation district heating and cooling network. [ABSTRACT FROM AUTHOR]

Milled peat must be dried for the production of peat fuel briquettes. The current trend in the creation of drying technologies is the intensification of the dehydration process while obtaining a high-quality final product. An increase in the temperature of the drying agent, above 300 °C, significantly accelerates the reaching of the final moisture content of the peat. In the final stage, it is also accompanied by partial thermal decomposition of the solid phase. Its first stage, which is the decomposition of hemicellulose, contributes to a decrease in weight and an increase in the caloric content of the dry residue. The development of high-temperature drying modes consists of determining the temperature and velocity of the drying agent, wherein the duration of the material reaching the equilibrium moisture content will be minimal and the temperature of the material will not rise above the second-stage decomposition temperature of cellulose. This problem can be solved by the mathematical modeling of the dynamics of peat particles drying in the flow. The article presents a mathematical model of heat and mass transfer, phase transitions, and shrinkage during the dehydration of milled peat particles. The equations of the mathematical model were built based on the differential equation of mass transfer in open deformable systems, which, in the absence of deformations, turns into the known equation of state. A numerical method for implementing a mathematical model has been developed. The adequacy of the mathematical model is confirmed by comparing the results of numerical modeling with known experimental data. [ABSTRACT FROM AUTHOR]

Fast humidity sensors are of interest due to their potential application in new sensing technologies such as wearable personal healthcare and environment sensing devices. However, the realization of rapid response/recovery humidity sensors remains challenging primarily due to the sluggish adsorption/desorption of water molecules, which particularly impacts the response/recovery times. Moreover, another key factor for fast humidity sensing, namely the attainment of equal response and recovery times, has often been neglected. Herein, the layer-by-layer (LbL) assembly of a reduced graphene oxide (rGO)/polyelectrolyte is demonstrated for application in fast humidity sensors. The resulting sensors exhibit fast response and recovery times of 0.75 and 0.85 s (corresponding to times per RH range of 0.24 and 0.27 s RH−1, respectively), providing a difference of only 0.1 s (corresponding to 0.03 s RH−1). This performance exceeds that of the majority of previously reported graphene oxide (GO)- or rGO-based humidity sensors. In addition, the polyelectrolyte deposition time is shown to be key to controlling the humidity sensing kinetics. The as-developed rapid sensing system is expected to provide useful guidance for the tailorable design of fast humidity sensors. [ABSTRACT FROM AUTHOR]

The purpose of this work was to develop, characterize and test new low-cost materials suitable for removing methylene blue dye from water and wastewater by adsorption. The solid materials consisted of silica gel powder (SG), silica gel mixed with eggshell powder (SG-ES) and a mixture of silica gel with sand from the western Iraqi desert (SG-SI). The samples were milled by using an electrical mixer and a ball mill, followed by a drying step. In addition, desert sand was acid-treated in order to remove impurities. The structure and chemical composition of the samples were investigated by X-ray diffraction (XRD), a scanning electron microscopy technique equipped with an energy-dispersive X-ray spectrometer (SEM-EDX), a low-temperature nitrogen adsorption (BET) technique, thermo-analytical (TG/TGA) measurements and Fourier-transformed infrared spectroscopy (FTIR). The previously mentioned materials were tested to remove methylene blue from an aqueous solution. The adsorption experiments were monitored by ultraviolet–visible (UV-Vis) spectrophotometry and showed that SG and SG-ES gave promising results for the methylene blue removal from water. After 40 min of treatment of the aqueous solution containing 10 mg/L of MB at room temperature, the tested SG, SG-ES and SG-SI materials were found to have 86%, 80% and 57% dye adsorption efficiency, respectively. Taking into consideration not only the adsorption activity of the studied material but their availability, cost and concepts of cleaner production and waste minimization, the developed silica gel with eggshell can be considered as a good, cost-effective alternative to commercially available activated-carbon-based adsorbents. Different kinetic and isotherm models were fitted to the experimental results. A pseudo-second-kinetics-order model revealed high correlation fitting, while the Freundlich model was found to appropriately describe the adsorption isotherm. The thermal stability during the possible regeneration process of the SG-ES adsorbent mixture and its interaction mechanism with cationic dye was discussed. [ABSTRACT FROM AUTHOR]

Dry eye disease (DED) is a common ocular disorder characterized by an inadequate lubrication of the eye by tears leading to inflammation and the alteration of the ocular surface. Current treatments are often limited due to their side effects and ineffectiveness. Thymoquinone (TQ) is a natural compound present in the essential oil of Nigella sativa L., with anti-inflammatory and antioxidant activities. In this study, conventional and hyaluronic acid-coated liposomes were developed to improve TQ activity at ocular level. In the present study, the cytoprotective effects of TQ or TQ liposomes were assessed against oxidative and inflammatory processes in human corneal epithelial cells (HCE-2). Hyperosmolarity conditions (450 mOsm) were used as a model of DED. Interleukin-1β (IL-1β), Interleukin-6 (IL-6) and tumor necrosis factor (TNFα) were quantified by quantitative real-time polymerase chain reaction (RT-qPCR); COX-2 and Phospho-NF-κB p65 (p-p65) by Western blotting (WB). Moreover, the mitochondrial reactive oxygen species (mtROS) levels were measured by MitoSOX assay. The hyperosmotic treatment induced a significant increase of the proinflammatory genes and proteins expression that were significantly decreased in the liposomes-treated cells. The coincubation with hyaluronic acid-coated liposomes significantly reverted the increase of mtROS production, evidently stimulated by the hyperosmotic stress. Our data suggest that TQ-loaded liposomes have potential as a therapeutic agent in dry eye disease, improving the TQ efficacy. [ABSTRACT FROM AUTHOR]

Ionic polymer–metal composites (IPMCs) have attracted attention in recent years due to their integration of actuation and sensing functions. As one of the main sensing functions of IPMCs, humidity sensing has been of consistent interest in wearable health monitors and artificial skin. However, there are still some technical challenges in that classical IPMCs have poor humidity sensing performance due to their dense surface electrode, and IPMCs are damaged easily due to an electrode/membrane mismatch. In this work, through the spraying and electrodepositing process, we developed an efficient method to rapidly prepare a Au-shell-Ag-NW (silver nanowire)-based IPMC with high strength, low surface resistance and excellent humidity sensing performance. Meanwhile, we optimized the preparation method by clarifying the influence of solvent type and electrodepositing time on the performance of the Au-shell-Ag-NW-based IPMC, thus effectively improving the humidity sensing effect and strength of the IPMC. Compared with previous research, the humidity electrical response (~9.6 mV) of the Au-shell-Ag-NW-based IPMC is at least two orders of magnitude higher than that of the classical IPMC (~0.41 mV), which is mainly attributed to the sparse gap structure for promoting the exchange of water molecules in the environment and Nafion membrane, a low surface resistance (~3.4 Ohm/sq) for transmitting the signal, and a seamless connection between the electrode and Nafion membrane for fully collecting the ion charges in the Nafion membrane. Additionally, the Au-shell-Ag-NW-based IPMC could effectively monitor the human breathing process, and the humidity sensing performance did not change after being exposed to the air for 4 weeks, which further indicates that the Au-shell-Ag-NW-based IPMC has good application potential due to its efficient preparation technology, high stability and good reproducibility. [ABSTRACT FROM AUTHOR]

Highlights: What are the main findings? A hybrid desiccant M-cycle cooling system with an HDH unit is proposed for simultaneous cooling and water production. Three typical operational modes are analysed and compared in terms of cooling and water production. What is the implication of the main finding? The recirculation mode exhibited a superior cooling performance than the other two modes. The water production rates and system COP were similar among the three modes. In this paper, the cooling and freshwater generation performance of a novel hybrid configuration of a solid desiccant-based M-cycle cooling system (SDM) combined with a humidification–dehumidification (HDH) desalination unit is analysed and compared in three operational modes: ventilation, recirculation, and half recirculation. The HDH unit in this system recycles the moist waste air sourced from the M-cycle cooler and rotary desiccant wheel of the SDM system to enhance water production. A mathematical model was established and solved using TRNSYS and EES software. The results of this study indicate that the recirculation mode exhibited superior cooling performance compared to the other two modes, producing up to 7.91 kW of cooling load and maintaining a supply air temperature below 20.85 °C and humidity of 12.72 g/kg under various ambient conditions. All the operational modes showed similar water production rates of around 52.74 kg/h, 52.43 kg/h, and 52.14 kg/h for the recirculation, half-recirculation and ventilation modes, respectively, across a range of operating temperatures. The recirculation mode also exhibited a higher COP compared to the other modes, as the environmental temperature and relative humidity were above 35 °C and 50%. However, it should be noted that the implementation of the recirculation mode resulted in a higher water consumption rate, with a maximum value of 5.52 kg/h when the inlet air reached 45 °C, which partially offset the benefits of this mode. [ABSTRACT FROM AUTHOR]

The developed chemosensitive layers consisted of multi-walled carbon nanotubes (MWCNTs), reduced graphene oxide (rGO), and a conductive polymer (polyaniline—PANI) in a polymeric matrix (a polystyrene solution in methylene chloride). The layers were challenged with a test gas to determine the optimum variant in terms of sensitivity to the selected analyte and the repeatability of results. In terms of individual components, the greatest percentage change in resistance (32%) and the best repeatability were found for chemosensitive layers containing a PANI salt in the polymeric matrix. Even greater changes in resistance were exhibited by sensors containing more than one active component in the matrix: 45% for PANI + MWCNTs and 75% for PANI + rGO. The presented method of thin-layer deposition was shown to be suitable for the production of sensitive and functional sensors of ammonia vapors. The developed sensors were characterized by high repeatability and sensitivity to a harmful substance that constitutes an inhalation hazard to workers. The sensors were also analyzed for their durability and recovery as well as the ability to function under varying temperature and humidity conditions. [ABSTRACT FROM AUTHOR]

A point-of-care (POC) diagnostic is needed for both women and men to establish universal screening and surveillance for the number one, non-viral sexually transmitted infection (STI) caused by Trichomonas vaginalis. We developed a POC diagnostic for this STI using the MedMira Rapid Vertical Flow (RVF®) Technology test cartridge with a membrane that includes a Vertical procedural/reagent control line (referred to as CVL) and spotted with 1 µg of a 72.4-kDa truncated version of α-actinin called ACT::SOE3. This protein is a specific diagnostic target for antibody in sera of individuals with trichomoniasis. Serum antibody to ACT::SOE3 is a positive reaction with the test spot. Specificity of ACT::SOE3 was revealed with monoclonal antibodies (MAbs) generated to ACT::SOE3. Addition of negative control serum with MAb 67B reactive to ACT::SOE3 shows detection of both ACT::SOE3 and the CVL. Only positive sera of individuals had antibody reactive with ACT::SOE3 and detected the presence of the spot and the CVL. Negative control sera were unreactive with ACT::SOE3 and only showed the presence of the CVL. Importantly, to show proof-of-principle for POC application, ACT::SOE3 was detected with the positive patient sera spiked with whole blood. Finally, packaged cartridges stored with desiccant packs at 37 °C for one year gave identical results with the positive and negative human sera. Our results show the validity of this new POC serodiagnostic for this STI. [ABSTRACT FROM AUTHOR]

In this paper, the use of Metal-Organic Framework (MOF) materials as an option for the energy efficiency enhancement of HVAC systems is investigated. In particular, the possibility of using MOFs as dehumidifying materials to reduce the latent load associated with the moisture content of the airflows is studied. A literature review is proposed, highlighting the benefits of using MOFs instead of other adsorbents (e.g., silica-gel) and discussing the unique features (high water uptake capacity and low regeneration temperatures) that make MOFs a preferential desiccant. The possibility to finely tune these properties is also underlined, reporting some explicative examples. A theoretical proposal of a psychrometric transformation, to be performed in a HVAC system equipped with a MOF-Assisted Dehumidifier (MAD), is presented. This transformation is compared with a traditional one (cooling and dehumidification operated by a cooling coil with low temperatures of the coolant). The preliminary numerical simulations, conducted on a reference case study in Florence, Italy, show an estimated energy saving of 30–50%, leading us to consider the use of this technology as a very competitive one in the air-conditioning sector. [ABSTRACT FROM AUTHOR]

Rice bran is a by-product of the rice milling process. It contains a high concentration of protein. Rice brans are frequently utilized as feed cattle, fertilizer, and fuel. However, their application as human nutrition supplements is uncommon, and the necessary process for this purpose is yet to be established, including the drying process. This study aims to evaluate the effect of the spray-drying parameters, the inlet temperature, inlet flowrate, and inlet air flowrate, on rice bran protein (RBP) powder and optimize it using response surface methodology (RSM). A thermal water-based extraction method was utilized prior to the drying process. The correlation between the spray-drying parameters, i.e., the inlet temperature (120 to 210 °C), feed flowrate (5 to 55%), and air flowrate (246 to 670 L/h), and the RBP yield were investigated. The quality of the RBP powder was evaluated based on acid amino profiling in the mixture through de novo peptide sequencing. The optimized operating conditions for the maximum yield of RBP powder (25.7 g RBP/100 g RRB) are 178 °C, feed flowrate of 25%, and air flowrate of 450 L/h. The main peptides that contribute to RBP powder protein are globulin and glutelin; meanwhile, prolamin is believed to degrade during the drying process. The process also produced protein sugar, helping to produce fine particles powder without the drying agent. [ABSTRACT FROM AUTHOR]

In this study, the control of a desiccant-wheel-based evaporative cooling system with a double-layer dew-point cooler system is emphasized. There are two dew-point evaporative coolers in the system and the air taken inside is subjected to pre- and post-cooling processes. The dehumidification process of the air taken in is carried out by the desiccant wheel after the pre-cooling process. A proportional-based control strategy has been developed to adjust the temperature and relative humidity of the room quickly and robustly with different operation modes for actuators to bring comfort with less energy consumption. In addition, an automatic Stop/Run mode has been added to the control strategy to save extra energy. With the developed control strategy, enabling the actuators to switch between the operation modes, more energy savings are achieved compared to both traditional ON/OFF and proportional controls. The accuracy and applicability of the developed control strategy were analyzed and it was observed that the room comfort reached the desired levels successfully under all disruptive effects. The control inputs and the energies consumed by all the actuators were investigated and it was determined that 21.19% more energy savings are provided by adding the automatic Stop/Run feature. With the multi-mode control strategy, a total of 40.90% less energy consumption is achieved compared to the classical ON/OFF control technique. Thus, it is seen that the controller developed for the desiccant-wheel-based evaporative cooler is a viable method to provide fast and robust comfort conditions with less energy. [ABSTRACT FROM AUTHOR]

Harvesting atmospheric water by solar regenerated desiccants is a promising water source that is energy-efficient, environmentally clean, and viable. However, the generated amounts of water are still insignificant. Therefore, more intensive fundamental research must be undertaken involving experiments and modeling. This paper describes several experiments, which were conducted to predict and improve the behavior of water absorption/desorption by the Calcium Chloride (CaCl2) desiccant, where the uncertainty did not exceed ±3.5%. The absorption effect in a deep container was studied experimentally and then amplified by pumping air into the solution. The latter measured water absorption/desorption by a thin solution layer under variable ambient conditions. Pumping air inside deep liquid desiccant containers increased the water absorption rate to 3.75% per hour, yet when using a thin layer of the solution, it was found to have increased to 6.5% per hour under the same conditions. The maximum amount of absorbed water and water vapor partial pressure relation was investigated, and the mean absolute error between the proposed formula and measured water content was 6.9%. An empirical formula, a one-dimensional mathematical model, was then developed by coupling three differential equations and compared to experimental data. The mean absolute error of the model was found to be 3.13% and 7.32% for absorption and desorption, respectively. Governing mathematical conservation equations were subsequently formulated. The mathematical and empirical models were combined and solved numerically. Findings obtained from the simulation were compared to experimental data. Additionally, several scenarios were modeled and tested for Jeddah, Saudi Arabia, under various conditions. [ABSTRACT FROM AUTHOR]