Liquid Absorption Research Articles

Unraveling the permeation-enhancing effect of didecyl dimethyl ammonium chloride (DDAC) on poplar wood (Populus cathayana Rehd.)

ABSTRACT Wood is a sustainable, porous material with a diverse range of applications. However, the low permeability of liquids within wood poses significant challenges for the widespread application of advanced wood-based materials such as oil–water separation, as well as traditional chemical modification processes of wood. Surfactants exhibit potential to improve permeability of liquids within wood by effectively enhancing liquid wettability on solid surfaces. In this study, the effects of didecyl dimethyl ammonium chloride (DDAC) on liquid absorption of water and copper ethanolamine (CE) by wood were explored under atmospheric temperature and pressure. With an increase in concentration of DDAC, its promotion effect on liquid absorption of wood became more pronounced. The most notable enhancement was observed in wicking test where 0.10% DDAC increased liquid absorption of wood to water by 156.7% and to CE by 65.5%. The enhancement of liquid wettability on wood surface cannot be solely attributed to reduction of liquid surface tension, the adsorption of DDAC onto wood surface also plays a crucial role in this process. This study investigated the intrinsic mechanisms by which DDAC enhanced the permeability of liquids within wood, contributing to increased productivity and reduced energy consumption.

Development of 5-fluorouracil/etoposide co-loaded electrospun nanofibrous scaffold for localized anti-melanoma therapy.

Nanofibrous scaffolds have emerged as promising candidates for localized drug delivery systems in the treatment of cutaneous cancers. In this study, we prepared an electrospun nanofibrous scaffold incorporating 5-fluorouracil (5-FU) and etoposide (ETP) for chemotherapy targeting melanoma cutaneous cancer. The scaffold was composed of polyvinyl alcohol (PVA) and chitosan (CS), prepared via the electrospinning process and loaded with the chemotherapeutic agents. We conducted relevant physicochemical characterizations, assessed cytotoxicity, and evaluated apoptosis against melanoma A375 cells. The prepared 5-FU/ETP co-loaded PVA/CS scaffold exhibited nanofibers (NFs) with an average diameter of 321 ± 61 nm, defect-free and homogenous morphology. FTIR spectroscopy confirmed successful incorporation of chemotherapeutics into the scaffold. Additionally, the scaffold demonstrated a hydrophilic surface, proper mechanical strength, high porosity, and efficient liquid absorption capacity. Notably, sustained and controlled drug release was observed from the nanofibrous scaffold. Furthermore, the scaffold significantly increased cytotoxicity (95%) and apoptosis (74%) in A375 melanoma cells. Consequently, the prepared 5-FU/ETP co-loaded PVA/CS nanofibrous scaffold holds promise as a valuable system for localized eradication of cutaneous melanoma tumors and mitigation of adverse drug reactions associated with chemotherapy.

Robust and Wet Adhesive Self-Gelling Powders for Rapid Hemostasis and Efficient Wound Healing.

Healing traumatic wounds is arduous, leaving miscellaneous demands for ideal wound dressings, such as rapid hemostasis, superior wet tissue adhesion, strong mechanical properties, and excellent antibacterial activity. Herein, we report a self-gelling, wet adhesive, stretchable (polyethylenimine/poly(dimethylammonium chloride)/(poly(acrylic acid)/poly(sodium styrenesulfonate)/alkylated chitosan)) ((PEI/PDDA)/(PAA/PSS)/ACS) powder as a new option. The self-gel utilizes noncovalent interactions among in situ formed PDDA/PSS nanoparticles and PEI/PAA polymetric matrices to earn sensational mechanical properties and tensile strength while incorporating ACS to obtain fast hemostasis and therapeutic capacities. The powder can form a hydrogel patch in situ within 3 s upon liquid absorption, capable of resisting pressure higher than twice the blood pressure. Deposition of the self-gelling powders on various wounds, such as rat liver and femoral artery wounds, can stop bleeding in 10 s and lessen the amount of bleeding 6-fold plus in corresponding models. Furthermore, the self-gelling powders can significantly advance the chronic wound healing process by displaying a high wound healing rate and a low inflammatory response and promoting the formation of new blood vessels and tissue regeneration. The satisfactory mechanical properties, strong wet adhesion, sufficient antibacterial properties, ease of usage, adaptability to complex wounds, rapid hemostasis, and superior therapeutic capacities of (PEI/PDDA)/(PAA/PSS)/ACS self-gelling powders render them as a profound wound dressing biomaterial.

Photoinduced Puffing with Large Volume Expansion and Photomechanical Motions induced by Topochemical [4+4] Reactions in Molecular Crystal Solvates.

In this work, we report the first example of two crystal solvates of an anthracene-benzhydrazide based molecule (Ant) that display very distinct photo-responsive behaviour when 365 or 405 nm or visible light is illuminated. For the first time, the crystal hydrate that has water molecule in the lattice (hereafter named as Ant-H2O) display fascinating puffing behavior with large volume expansion upto 50 % accompanied with surface modulation when illuminated with 405 nm light, a phenomenon very much similar to the rice or popcorn puffing by thermal treatment. Utilizing the properties of photoconverted Ant-H2O crystals, we have demonstrated their application in photoinduced enhanced liquid absorption using various liquids/solutions. The other crystal solvate having DMF in the crystal lattice (hereafter named as Ant-DMF) responds to 405 nm light by bending, twisting, chopping, jumping or splitting etc. The chopping of Ant-DMF crystal was also observed under ambient/white light but at a slower rate compared to 405 nm light. Single crystal X-ray diffraction study reveals that the photoinduced puffing and photomechanical effects of these materials are rooted to the topochemical [4+4] cycloaddition reaction between the anthracene moieties that facilitate molecular packing change assisted by the reconfiguration of intermolecular non-covalent interactions involving lattice trapped solvent molecules.

3D printed electrically conductive amine based sorbent for CO2 capture

CO2 capture technologies are key to the ongoing energy transition towards a low-carbon future. Solid adsorption is a promising technology for carbon capture with potential energy savings for regeneration of the material compared to liquid absorption. An interesting route for regeneration is electrical swing adsorption (ESA). An electrically conductive sorbent for direct air capture (DAC) was developed by 3D printing. As sorbent material an amine based ion-exchange resin was selected based on its high CO2 capacity for DAC with silver coated glass flakes as electrically conductive additive. Different amount of flakes were added to study the percolation threshold of the sorbent. The heating of the sorbents was done by Joule heating and monitored by an infrared camera. Furthermore, the influence of humidity and temperature on the electrical resistivity and volume of the sorbent structures were evaluated.Solid amine based sorbents with 15 to 35 vol% of silver coated glass flakes were successfully printed. At 20 vol% of flakes, a higher electrical conductivity could be obtained at room temperature and lower humidity. If the humidity increases up to 75 %, the volume of the structures expands with 7 % which causes an increase in electrical resistivity and loss of percolation. At 25 vol% of flakes, percolation is obtained and the resistivity is low enough (<10 Ohm.m) for Joule heating. This resistivity resulted in a heating time of 60 s for heating up to 70 °C, the regeneration temperature of the sorbent. These experiments demonstrate that printed solid amine based sorbent were successfully developed for CO2 capture and regeneration by ESA.

Revealing the behavior and mechanism of surfactant-assisted liquid permeability in Poplar wood

Wood is a sustainable and porous resource that can be utilized to fabricate advanced functional materials. However, the low permeability of liquids within wood poses a challenge to widespread adoption and implementation of technology for producing wood-based functional materials. Surfactants are capable of reducing surface tension of liquids, thus holding promise for enhancing liquid permeability in wood. The effect of four surfactants (JFC-U, Tween 80, OP-10, DDAC) on liquid absorption of copper ethanolamine (CE) in wood was investigated under room temperature and pressure. Surfactants effectively increased liquid absorption of wood up to 2.3 times and weight percent gain by up to 5.8 times compared with that of CE control. The improvement effect of surfactants resulted from three aspects: significantly improved liquid wetting on wood surface, enhanced penetration of liquid in cell lumen, and promoted molecular movement within cell wall. Their contributions varied with the structure of surfactants. Surfactants with linear structure showing significantly reduced surface tension, and cationic surfactants exhibiting high adsorption capacity on wood surface both demonstrated superior efficacy in increasing liquid permeability. This study explored the mechanisms by which surfactants affect liquid permeability within wood, while also provided guidance to select effective surfactants to assist wood impregnation.

Experimental and parametric study in pool boiling enhancement with self-induced jet impingement on the microporous copper surface using R1336mzz(Z)

Enhancing pool boiling performance is of significant interest for cooling high-power electronics. This paper introduces a self-induced jet impingement device designed for practical boiling enhancement. Using R1336mzz(Z) as the working fluid, we performed an experimental and parametric study on a microporous copper surface, considering the distinct characteristics of this device. Our results demonstrate that, due to the promotion of bubble detachment and the ensuring of sustained liquid absorption, the self-induced jet impingement device augments the Critical Heat Flux (CHF) on the microporous copper surface effectively. Nonetheless, the large predominant size of nucleation sites on this surface highlights the boiling suppression effect from jet impingement, resulting in a minor decrease in the Nucleate Boiling Heat transfer coefficient (hNB). Parametric evaluations reveal that strategies promoting the circulation flow of working fluid have a positive impact on CHF enhancement. Conversely, this device might negatively influence boiling heat transfer on microporous copper surface under conditions of liquid scarcity due to the restricted total flow area of jet holes. Our study indicates CHF and hNB@CHF enhancements of up to 196.0% and 291.0%, culminating in 73.7 W/cm2 and 78.2 kW/(m2∙K), respectively, compared to the boiling performances of standard pool boiling on the non-microporous copper surface.

Effect of Fly Ash on the Mass Transfer Performance of CO2 Removal Using MEA and DEA Solutions in a Packed Tower

The accumulation of uncollected fly ash from flue gas in post-combustion CO2 capture processes is a significant concern in current coal-fired power plants due to its potential impact on the performance of CO2 absorbent and absorption towers. In order to determine the effect of fly ash on the mass transfer performance of CO2 absorption into monoethanolamine (MEA) and diethanolamine (DEA) aqueous solutions, experimental studies were carried out using a small-sized packed tower equipped with θ-ring random packing. These studies were conducted under various operating parameters, including solution temperature, liquid/gas ratio (L/G), packing height, and fly ash concentration. The results show that the effect of fly ash on the outlet CO2 concentration was primarily observed during the initial stages of the experimental process. Moreover, the presence of fly ash leads to a reduction in the volumetric overall mass transfer coefficient (KGav) when using MEA and DEA solution, and increasing the fly ash concentration further exacerbates this negative impact. However, the effect of fly ash on the reduction in KGav is not significantly related to its chemical composition but rather depends on the operational parameters. With increasing solution temperature, liquid/gas ratio (L/G), and packing height, the KGav values for different solutions exhibit an upward trend. The negative effect of fly ash on KGav remains relatively stable for MEA as solution temperature and packing height increase. Compared to MEA, fly ash has a greater negative effect on DEA solution under the same experimental conditions. The analysis reveals that the detrimental effect of fly ash on KGav primarily stems from its ability to alter the distribution state of the absorption liquid within the packed tower.

Dynamic measurement of airway surface liquid volume with an ex vivo trachea-chip.

The volume and composition of airway surface liquid (ASL) is regulated by liquid secretion and absorption across airway epithelia, controlling the pH, solute concentration, and biophysical properties of ASL in health and disease. Here, we developed a method integrating explanted tracheal tissue with a micro-machined device (referred to as "ex vivo trachea-chip") to study the dynamic properties of ASL volume regulation. The ex vivo trachea-chip allows real-time measurement of ASL transport (Jv) with intact airway anatomic structures, environmental control, high-resolution, and enhanced experimental throughput. Applying this technology to freshly excised tissue we observed ASL absorption under basal conditions. The apical application of amiloride, an inhibitor of airway epithelial sodium channels (ENaC), reduced airway liquid absorption. Furthermore, the basolateral addition of NPPB, a Cl- channel inhibitor, reduced the basal rate of ASL absorption, implicating a role for basolateral Cl- channels in ASL volume regulation. When tissues were treated with apical amiloride and basolateral methacholine, a cholinergic agonist that stimulates secretion from airway submucosal glands, the net airway surface liquid production shifted from absorption to secretion. This ex vivo trachea-chip provides a new tool to investigate ASL transport dynamics in pulmonary disease states and may aid the development of new therapies targeting ASL regulation.

Bacterial nanocellulose/calcium alginate hydrogel for the treatment of burns.

Bacterial cellulose (BC) has shown high capacity for the treatment of wounds and burns, providing a moisty environment. Calcium alginate can be associated with BC to create gels that aid in wound debridement and contribute to appropriate wound healing. This study is aimed at characterizing and evaluating the use of bacterial cellulose/alginate gel in skin burns in rats. Cellulose and cellulose/alginate gels were compared regarding the capacity of liquid absorption, moisture, viscosity, and potential cytotoxicity. The 2nd degree burns were produced using an aluminum metal plate (2.0cm) at 120ºC for 20s on the back of rats. The animals were divided into non-treated, CMC(Carboxymethylcellulose), Cellulose(CMC with bacterial cellulose), and Cellulose/alginate(CMC with bacterial cellulose and alginate). The animals received topical treatment 3 times/week. Biochemical (MPO, NAG and oxidative stress), histomorphometry and immunohistochemical assays (IL-1β IL-10 and VEGF) were conducted on the 14th, 21st, 28th, and 35th days. Cellulose/Alginate gel showed higher absorption capacity and viscosity compared to Cellulose gel, with no cytotoxic effects. Cellulose/alginate presented lower MPO values, a higher percentage of IL-10, with greater and balanced oxidative stress profile. The use of cellulose/alginate gel reduced neutrophils and macrophage activation and showed greater anti-inflammatory response, which can contribute to healing chronic wounds and burns.

Mechanism of Xinshubao Tablets in exerting anti-inflammatory, vasodilation, and cardioprotective effects based on network pharmacology

This study aims to explore the anti-inflammatory, vasodilation, and cardioprotective effects of the intestinal absorption liquids containing Xinshubao Tablets or single herbs, and to elucidate the potential mechanism based on network pharmacology. Western blot was then conducted to validate the expression changes of core proteins. Lipopolysaccharide(LPS)-stimulated RAW264.7 cells were used to observe the anti-inflammatory effect. The vasodilation activity was examined by the microvessel relaxation assay in vitro. Oxygen-glucose deprivation(OGD)-induced H9c2 cells were used to investigate the cardioprotective effect. The chemical components were retrieved from Herb databases and composition of Xinshubao Tablets drug-containing intestinal absorption solution. Drug targets were retrieved from SwissTargetPrediction databases. GeneCards was searched for the targets associated with the anti-inflammatory, vasodilation, and cardioprotective effects. The common targets shared by the drug and the effects were used to establish the protein-protein interaction(PPI) network, from which the core targets were obtained. Finally, the core targets were imported into Cytoscape 3.9.1 for Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) analyses. The anti-inflammatory experiment showed that both Xinshubao Tablets and the single herbs constituting this formula had anti-inflammatory effects. Curcumae Radix had the strongest inhibitory effect on the production of tumor necrosis factor-α(TNF-α), and Salviae Miltiorrhizae Radix et Rhizoma had the strongest inhibitory effect on the generation of interleukin-6(IL-6). Xinshubao Tablets, Curcumae Radix, and Crataegi Fructus had vasodilation effect, and Crataegi Fructus had the strongest effect. Xinshubao Tablets, Salviae Miltiorrhizae Radix et Rhizoma, Acanthopanacis Senticosi Radix et Rhizoma seu Caulis, and Paeoniae Radix Alba had cardioprotective effects, and Salviae Miltiorrhizae Radix et Rhizoma had the strongest cardioprotective effect. Network pharmacology results demonstrated that except the whole formula, Salviae Miltiorrhizae Radix et Rhizoma had the most components with anti-inflammatory effect, and Curcumae Radix had the most components with vasodilation and cardioprotective effects, followed by Salviae Miltiorrhizae Radix et Rhizoma. The nitric oxide synthase 3(NOS3) was predicted as the core target for the anti-inflammatory, vasodilation, and cardioprotective effects. Western blot results showed that Xinshubao Tablets significantly up-regulated the expression of NOS3 in OGD-induced H9c2 cells. GO enrichment analysis showed that the effects were mainly related to lipid exported from cell, regulation of blood pressure, and inflammatory response. KEGG pathway enrichment predicted AGE-RAGE and HIF-1 signaling pathways as the key pathways.

The influence of viscose fibre properties on the absorbency of feminine hygiene tampons: the pivotal role of cross-sectional geometry

Feminine hygiene products, used by millions of women worldwide on a daily basis, come in various forms. Among them, tampons are a prominent type that aims to absorb menstrual blood directly in the vagina. However, the underlying mechanisms governing liquid absorption in tampons have received limited research attention and remain poorly understood. This study aims to investigate these mechanisms by examining the two main types of viscose fibres used in tampons and their effects when employed in tampon production. The sole distinction between the fibre types lies in their geometric shape—round or trilobal—while all other fibre parameters remain constant. To explore these mechanisms, tampon proxies made from these fibres were created and subjected to tests measuring liquid absorption. In addition, a novel method employing infrared thermography was utilized to infer the stored energy within the compressed tampon. Furthermore, individual fibres were characterised for chemical composition, surface properties, fine structure, liquid interaction, mechanical parameters, and friction behaviour. The results revealed that trilobal fibres exhibited higher tampon absorbency compared to their round counterparts, despite sharing similar chemical composition and comparable mechanical characteristics. This disparity can be attributed to the greater specific surface area of trilobal fibres, leading to enhanced liquid uptake through fibre swelling. However, single fibre swelling only accounted for a minor fraction of the total liquid absorbency of a tampon. The most influential fibre parameter was the geometric shape, as trilobal fibres facilitated the construction and maintenance of a bulkier network with increased available volume for liquid absorption.Graphic abstract

Characterization of Natural and Synthetic Fabrics for the Treatment of Complex Wastes.

In the present study, nine fabrics have been tested for brackish water treatment with the aim of industrial application under the concept of zero liquid discharge (ZLD). Moisture content was determined, where it was observed that the lignocellulosic fabrics had a moisture content ranging from 2.5 to 8.5%. The wetting contact angle showed that the flax with polylactic acid (LPLA) was the most hydrophobic. The determination of the liquid absorption capacity showed that, of the synthetic fabrics, the one with the highest absorption, both in distilled water and in brackish water, was the polyester (PES) fabric with an absorption of 816% compared to its initial weight. In the natural fabrics, the highest absorption capacity was shown by the wet-laid without treatment (WL-WT) fabric for both distilled water and brackish water, although it required several cycles of operation to maintain this stable absorption. Exposure to brackish water improved the absorption capacity of all samples. Mechanical and thermal characterization showed that the synthetic fabrics were more resistant than the natural fabrics, although they may compete in terms of applicability. The capillarity study showed that the most hydrophilic fabrics completed the test the fastest. Finally, the composting degradation test showed that those fabrics with polylactic acid (PLA) content degraded faster in the first 14 days and thereafter the degradation of the lignocellulosic content showed a slower degradation until 112 days. The Bam fabric did not degrade during the course of the experiment.

Increased ENaC-mediated liquid absorption across vitamin-D deficient human airway epithelia.

Vitamin D deficiency is a risk factor for exacerbation of obstructive airway disease, a hallmark of which is mucus dehydration and plugging. Calcitriol (the active form of vitamin D) deficiency in cultured human airway epithelia resulted in increased SCNN1G and ATP1B1 mRNAs encoding subunits of ENaC and the Na-K pump compared with supplemented epithelia. These drive the absorption of airway surface liquid. Consistently, calcitriol-deficient epithelia absorbed liquid faster than supplemented epithelia. Calcitriol deficiency also increased amiloride-sensitive Isc and Gt without altering Na-K pump activity, indicating the changes in amiloride-sensitivity arose from ENaC. ENaC activity can be regulated by trafficking, proteases, and channel abundance. We found the effect was likely not induced by changes to endocytosis of ENaC given that calcitriol did not affect the half-lives of amiloride-sensitive Isc and Gt. Furthermore, trypsin nominally increased Isc produced by epithelia ± calcitriol, suggesting calcitriol did not affect proteolytic activation of ENaC. Consistent with mRNA and functional data, calcitriol deficiency resulted in increased γENaC protein. These data indicate that the vitamin D receptor response controls ENaC function and subsequent liquid absorption, providing insight into the relationship between vitamin D deficiency and respiratory disease.NEW & NOTEWORTHY It is unknown why calcitriol (active vitamin D) deficiency worsens pulmonary disease outcomes. Results from mRNA, immunoblot, Ussing chamber, and absorption experiments indicate that calcitriol deficiency increases ENaC activity in human airway epithelia, decreasing apical hydration. Given that epithelial hydration is required for mucociliary transport and airway innate immune function, the increased ENaC activity observed in calcitriol-deficient epithelia may contribute to respiratory pathology observed in vitamin D deficiency.

Preparation and evaluation of blend polymer films for wound dressing using vancomycin-loaded polycaprolactone and carboxymethyl cellulose via crosslinking methods: Effect of mechanical strength, antibacterial activity, and cytotoxicity

Polycaprolactone (PCL) and carboxymethyl cellulose (CMC) are two materials with beneficial properties for wound healing applications. Here, the simple preparation of PCL/CMC polymer films via the crosslinking method was demonstrated for the first time. The polymer films represented the suitable properties of liquid absorption and tensile strength to be used as a wound dressing. The blend polymer films can also load the vancomycin, which prolongs the drug release for effectiveness against S. aureus. The trifluoroethanol showed less toxicity in comparison with other crosslinking agents. This process can also be applied further in other medical devices and wound healing applications.

Size Matters: A Computational Study of Hydrogen Absorption in Ionic Liquids.

We combined both density functional theory and classical molecular dynamics simulations to investigate the molecular mechanisms governing hydrogen solvation in a total of 12 ionic liquids. Overall, the analysis of the structural properties under high temperature and pressure conditions revealed weak interactions between hydrogen and the ionic liquids, with a slight preference of this gas to be placed at the apolar domains. Interestingly, those ionic liquids comprising nitrate anions allow the accommodation of hydrogen molecules also in the polar areas. The study of the hydrogen velocity autocorrelation functions supports this observation. In addition, the structure of all of the tested ionic liquids was almost insensitive to the addition of hydrogen, so the available free volume and cavity formation are presumably the most important factors affecting solubility.

Zingiber officinale and thymus vulgaris extracts co-loaded polyvinyl alcohol and chitosan electrospun nanofibers for tackling infection and wound healing promotion

Infections are severe complications associated with chronic wounds and tardy healing that should be timely treated to achieve rapid and proper tissue repair. To hinder such difficulties, a nanofibrous mat composed of polyvinyl alcohol and chitosan (PVA/CS) was developed by electrospinning method, containing thyme (Thymus vulgaris) and ginger (Zingiber officinale) extracts. The mat containing 10 wt% of the extracts (at the ratio of 50:50) exposed the nanofibers (NFs) with the nanoscale diameter (average 382 ± 60 nm), smooth surface, and defect-free morphology. Likewise, the relevant analyses of the loaded mat displayed high wettability, porosity, and liquid absorption capacity without any adverse interaction. The obtained mat also provided a high antioxidant activity, and its release profile was continuous and sustained for nearly 72 h. Besides, it inhibited the growth of both Gram-positive S. aureus and Gram-negative E. coli strains. Furthermore, the proposed mat significantly accelerated cutaneous wound healing in bacterial-infected rats by preventing bacteria growth at the wound site. At last, histopathology analysis confirmed the ample regeneration of skin structures, forming collagen fibers and appendages. Overall, the proposed mat containing ginger-thyme extracts provides multiple therapeutic capabilities with promising solutions for inhibiting wound infection and accelerating the healing process.

Exudate-Induced Gelatinizable Nanofiber Membrane with High Exudate Absorption and Super Bactericidal Capacity for Bacteria-Infected Wound Management.

Invasion of bacteria and continuous oozing of exudate are significant causes of interference with the healing of infected wounds. Therefore, an exudate-induced gelatinizable and near-infrared (NIR)-responsive nanofiber membrane composed of polyvinyl alcohol (PVA), carboxymethyl chitosan (CMC), and Fe-doped phosphomolybdic acid (Fe-PMA) with exceptional exudate absorption capacity and potent bactericidal efficacy is developed and denoted as the PVA-FP-CMC membrane. After absorbing exudate, the fiber membrane can transform into a hydrogel membrane, forming coordination bonds between the Fe-PMA and CMC. The unique exudate-induced gelation process imparts the membrane with high exudate absorption and retention capability, and the formed hydrogel also traps the bacteria that thrive in the exudate. Moreover, it is discovered for the first time that the Fe-PMA exhibits an enhanced photothermal conversion capability and photocatalytic activity compared to the PMA. Therefore, the presence of Fe-PMA provides the membrane with a photothermal and photodynamic therapeutic effect for killing bacteria. The PVA-FP-CMC membrane is proven with a liquid absorption ratio of 520.7%, a light-heat conversion efficiency of 41.9%, high-level generation of hydroxyl radical (•OH) and singlet oxygen (1O2), and a bacterial killing ratio of 100% for S. aureus and 99.6% for E. coli. The treatment of infected wounds on the backs of rats further confirms the promotion of wound healing by the PVA-FP-CMC membrane with NIR irradiation. Overall, this novel functional dressing for the synergistic management of bacteria-infected wounds presents a promising therapeutic strategy for tissue repair and regeneration.

The crucial role of nMOFs in H2S absorption process using ionic liquid solution based nanofluid systems

Ionic liquid solutions based of polyamines were synthesized and used for H2S removal. The results of simulation calculation and characterization showed that ionic liquid trap H2S by forming hydrogen bonds. Five nanometer-sized MOFs (nMOFs) were synthesized and added into ionic liquid solutions to build nanofluid systems. The effects of types, particle size, concentration, and regeneration gas of nanoparticles on the desulfurization performance of different nanofluids were explored. The addition of nMOFs with appropriate types and concentrations showed significant enhancement effect on the H2S absorption of liquid. Among five nMOFs, the systems of HKUST-1 and MIL-101(Fe) had high enhancement as well as regeneration performance at low concentrations (0.05 %). Based on sweep effect, gas–liquid mass transfer was enhanced by nMOFs due to the quickly capture and release of H2S. Furthermore, in this work, an “enrichment effect” has been proposed, in which H2S molecular enrichment zones were formed around nanoparticles, promoting gas–liquid reactions. The nanoparticles at different stages were characterized using X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscope and energy dispersive spectrum, and the results confirmed that nMOFs have the ability to enrich H2S, which play a catalyst-like and accelerator-like role in H2S absorption process.

Development of Transpiration-Type Thermoelectric-Power-Generating Material Using Carbon Nanotube Composite Papers with Capillary Action and Heat of Vaporization

A transpiration-type thermoelectric-power-generating paper based on previously developed carbon nanotube (CNT) composite paper, which is a composite material of CNTs and pulp that can generate thermoelectric power, was developed. The newly developed thermoelectric-power-generating material does not require an external high-temperature heat source due to the ability of paper to absorb liquid through capillary action and heat of vaporization generated when the liquid evaporates. The aim of this study is to investigate the feasibility of realizing the transpiration-type thermoelectric-power-generating paper. To begin with, the type of paper used as raw material for the composite paper was examined, and the fabrication process was modified in order to obtain more efficient liquid absorption based on capillary action. Then, the absorbing ability of the liquid was evaluated. Next, the feasibility of thermoelectric power generation using the heat of vaporization was confirmed. Moreover, for more efficient thermoelectric conversion, multisheet structures were also studied. Through several experiments, the material’s feasibility was verified, and it was confirmed that more power can be easily obtained through the use of multiple sheets. Specifically, a single sample spontaneously generated a temperature difference of up to 1.7 °C due to the heat of vaporization, generating an electromotive force of 36 μV. From the sample with a five-sheet structure, an electromotive force of 356 μV was obtained at a temperature difference of 2 °C. This material can be used in watery environments, such as rivers, lakes, and hot springs, and is expected to become a new energy-harvesting device.