Ether Research Articles

Unveiling dynamic alterations of lipid droplet polarity during NAFLD-triggered lipophagy utilizing a far-red fluorescent probe with large stokes shift

Lipophagy as a form of autophagy, can degrade lipid droplets, thereby acting as a critical regulator of cellular lipid metabolism, helping maintain the intracellular lipid homeostasis. In this study, we developed LP-SCUN, a far-red fluorescent probe for pinpointing lipid droplets with high sensitivity to solvent polarity. This probe allows for in situ imaging of lipophagy, tracking how lipid droplets move from non-polar to polar environments within lysosomes, leading to noticeable changes in fluorescence signals. The triphenylamine and triethylene glycol monomethyl ether groups of LP-SCUN facilitated its selective binding toward lipid droplets. Significantly, lipophagy and subsequent formation of autolysosomes decreased the environmental polarity, leading to a significant decrease in red fluorescence intensity (λex = 500 nm and λem = 643 nm). As such LP-SCUN was suitable for the in situ and real-time tracking of the cellular lipophagic processes. With this research we used LP-SCUN to elucidate the mechanism of lipid metabolism in liver cells of palmitate-induced hyperlipidemia cell models and high-fat diet-induced hyperlipidemia animal models. The results indicated that non-alcoholic fatty liver disease (NAFLD) can trigger an increase in cell lipophagy levels, while the inhibition of cell lipophagy can effectively alleviate the damage caused by NAFLD to cells and liver tissue in mice.

Synthesis, performance evaluation, and plasticization dynamics of biobased vanillic acid plasticizer for poly(vinyl chloride)

Phthalate-based plasticizers are widely used to improve the flexibility and ductility of engineering plastics. However, their hazardous toxicity and unsustainability have prompted the plastics industry to develop safe and efficient green plasticizers. Therefore, it is imperative to develop safe biobased plasticizers from renewable resources. The ether group had been introduced into renewable vanillic acid to synthesize vanillic acid ester derivatives (VAE) using a clean method, and characterized using various spectral methods. The application performances were compared for VAE and three commercial plasticizers for poly(vinyl chloride) (PVC) plasticization. Dynamic mechanical analysis (DMA) indicated that the presence of VAE could reduce the glass transition temperature of PVC by over 50 %, which is 32 % lower than induced by the dioctyl phthalate. The presence of carbonyl and ether groups in VAE increases the elongation at break of PVC by more than 12 times, and the elongation at break (419.8 %) is 10 % higher than that of acetyl tributyl citrate plasticized PVC. Thermogravimetric analysis and aging experiments indicated that PVC blend plasticized by VAE exhibited superior thermal stability compared to acetyl tributyl citrate. The interaction between PVC and the carbonyl and ether groups in VAE has been demonstrated through multifaceted analysis utilizing density functional theory calculations. The binding energy between fragments was −17.8 kcal/mol, and the interaction was visualized by IGMH. Under this interaction, VAE exhibited extremely low migration in PVC blends. Acute oral toxicity tests were used to demonstrate that VAE is harmless to rats even at high doses. Overall, VAE, as a sustainable, low-risk, and efficient PVC plasticizer, outperforms typical commercial plasticizers and is a promising alternative to phthalates.

The quorum sensing SinI/SinR-TraI/TraR systems promote Pb stabilization by Ensifer adhaerens S24 in the Pb-polluted aquatic environment

In this study, the Pb-resistant Ensifer adhaerens strain S24, which contains quorum sensing (QS) systems responsible for N-acyl homoserine lactone (AHL) production, was investigated for QS system-mediated Pb stabilization and the underlying mechanisms. Whole-genome sequence analysis revealed the QS SinI/R and TraI/R systems in strain S24. Subsequently, strains S24 and the S24∆sinI/R, S24∆traI/R, S24∆traI/R/sinR, and S24∆sinI/R-traI/R/sinR mutants were constructed and compared for QS SinI/SinR-TraI/TraR system-mediated Pb stabilization in the solution and the mechanisms involved. After 5 days of incubation, strain S24 significantly decreased the Pb concentration in the Pb-contaminated solution compared with the mutants. The S24∆sinI/R-traI/R/sinR mutant exhibited reduced Pb stabilization and AHL activity than the other mutants. The S24∆sinI/R-traI/R/sinR mutant had significantly greater Pb concentrations in the solution and lower cell surface-adsorbed and extracellular precipitated Pb (PbS) contents as well as lower expression of H2S-producing genes of metC and sseA than did strain S24. Furthermore, the S24∆sinI/R-traI/R/sinR mutant displayed reduced interactions between the hydroxyl, amino, carboxyl, and ether groups and Pb, compared with strain S24. These findings implied the vital role of the SinI/SinR-TraI/TraR systems in strain S24 for Pb stabilization through enhanced cell surface adsorption and extracellular precipitation in Pb-polluted aquatic environments.

Construction of a highly specific fluorescence “turn-on” probe for H2S detection and imaging in drug-induced live cells, zebrafish and mice arthritis models

Quantitatively and selectively detecting the biomarker of hydrogen sulfide (H2S) in arthritis diseases is of great significance for the early diagnosis and treatment of arthritis. Modern medical studies show that H2S as a biomarker is involved in the development of inflammation. In this work, a new highly specific fluorescence “turn-on” probe JMD-H2S was tailored for H2S detection and imaging in drug-induced live cells, zebrafish and mice arthritis models, which utilized pyrazoline molecule as the fluorescence signal reporter group and 2,4-dinitrophenyl ether group (DNB) with strong intramolecular charge transfer (ICT) effect as the H2S recognition moiety and fluorescence quenching group. JMD-H2S showed a fast response time (<60 s), a large fluorescence response ratio (enhanced ∼20 folds) at I453/I0, excellent sensitivity toward H2S over other analytes, and an outstanding limit of detection (LOD) as low as 25.3 nM. In addition, JMD-H2S has been successfully applied for detecting and imaging H2S in drug-induced live cells, zebrafish, and mice arthritis models with satisfactory results, suggesting it can be used as a robust molecular tool for investigating the occurrence and development of H2S and arthritis.

Silylation-Driven Volatility Enhancement in Mononuclear Calcium, Magnesium, and Barium Complexes with Monomethyl or Silyl Ether and Bis(diketonate).

Magnesium, calcium, and barium heteroleptic complexes were synthesized by the substitution reaction of the bis(trimethylsilyl)amide of Mg(btsa)2·DME, Ca(btsa)2·DME, and Ba(btsa)2·2DME with an ethereal group and hfac ligands (btsa = bis(trimethylsilyl)amide, DME = dimethoxyethane). The compounds Mg(dts)(hfac)2 (1), Ca(dts)(hfac)2 (2), Mg(dmts)(hfac)2 (3), Ca(dmts)(hfac)2 (4), and Ba(dmts)(hfac)2 (5) were fabricated and analyzed using various techniques, including Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, thermogravimetric analyses, and elemental analysis (dts = 2,2-dimethyl-3,6,9-trioxa-2-siladecane, dmts = 2,2-dimethyl-3,6,9,12-tetraoxa-2-silatridecane, hfac = hexafluoroacetylacetonate). The structures of complexes 2, 4, and 5 were confirmed using single-crystal X-ray crystallography; all complexes display monomeric structures. All compounds underwent trimethylsilylation of the coordinating ethereal alcohols (meeH and tmgeH) in the presence of HMDS as byproducts because of their increasing acidity originating from the electron-withdrawing hfac ligands. (meeH = 2-(2-methoxyethoxy)ethan-1-ol, tmgeH = tri(ethylene glycol) monoethyl ether, HMDS = hexamethyldisilazane).

Oxygen concentration regulated the efficient liquefaction of vulcanized natural rubber

Oxidative liquefaction represents a promising avenue for the homogeneous and high-value utilization of waste tire rubber. Given that truck tires predominantly comprise natural rubber (NR), this study investigated the efficient liquefaction of vulcanized NR regulated by oxygen concentration. Remarkably, the liquefaction of vulcanized NR was realized with an oxygen concentration of 75 % at 200 °C within 3 min. FTIR spectroscopy showed that carbonyl, ether and sulphoxide groups were produced during the liquification of NR vulcanizates. Oxygen concentration significantly affected the oxidative efficiency of both the main chains and crosslinks, with a more pronounced effect observed on the main chains. Nevertheless, the similar molecular weights and polydispersity indices across various degraded products suggested a selective oxidative cleavage of the NR backbone. Furthermore, online ATR-FTIR was used to monitor the dynamic changes of NR's molecular structure to elucidate the oxidative degradation mechanism. The oxidative cleavage of NR main chain primarily occurred at the C-C bonds connected with allyl groups, producing oxidized products enriched with conjugated carbonyl groups. Alternatively, the main chain scission may also occur due to the electronic rearrangement effect of the C=C bond and produce saturated carbonyl groups. Oxygen concentration modulated the degradation efficiency of vulcanized NR, which provided an efficient strategy for the upcycling of NR-based waste tires.

Structure-Activity Relationship of Benzophenazine Derivatives for Homogeneous and Heterogenized Photooxygenation Catalysis.

Singlet oxygen is a powerful oxidant used in various applications, such as organic synthesis, medicine, and environmental remediation. Organic and inorganic photosensitizers are commonly used to generate this reactive species through energy transfer with the triplet ground state of oxygen. We describe here a series of novel benzophenazine derivatives as a promising class of photosensitizers for singlet oxygen photosensitization. In this study, we investigated the structure-activity relationship of these benzophenazine derivatives. Akin to a molecular compass, the southern fragment was first functionalized with either aromatic tertiary amines, alkyl tertiary amines, aromatic sulfur groups, alkyl sulfur groups, or cyclic ethers. Enhanced photophysical properties (in terms of triplet excited-state lifetime, absorption wavelength, triplet state energy, and O2 quenching capabilities) were obtained with cyclic ether and sulfur groups. Conversely, the presence of an amine moiety was detrimental to the photocatalysts. The western and northern fragments were also investigated and slightly undesirable to negligible changes in photophysical properties were observed. The most promising candidate was then immobilized on silica nanoparticles and its photoactivity was evaluated in the citronellol photooxidation reaction. A high NMR yield of 97 % in desired product was obtained, with only a slight decrease over several recycling runs (85 % in the fourth run). These results provide insights into the design of efficient photosensitizers for singlet oxygen generation and the development of heterogeneous systems.

A comparative study of comprehensive performances for transparent plasticized polyvinyl chloride films with different plasticizers

AbstractFor flexible polyvinyl chloride (PVC) films with excellent mechanical performances and high transparency, the demand for antistatic properties is becoming increasingly urgent in textile and electronic fields. This study compares the effects of 60 phr bis (2‐(2‐butoxyethoxy) ethyl) adipate (DBEEA) with other five equal amounts of plasticizers on the conductivity, electrical stability, transparency, and mechanical properties of plasticized PVC. The infrared spectra of plasticizers indicate that there are unique ether groups exist in DBEEA. Then the calculated solubility parameters suggest the good compatibility between DBEEA and PVC. For conductivity, the volume resistivity and surface resistivity of the PVC sample with DBEEA (PVC/DBEEA) are 107 Ω· m and 1010 Ω, respectively, which are both lower by 3–4 orders of magnitude than that of other plasticized PVC. For electrical stability, the results indicate that PVC/DBEEA placed in air still maintains lowest resistivities. Under 10, 23, and 30°C, PVC/DBEEA keeps high and stable electrical properties. The similar refractive indices of DBEEA and PVC resin prepared by suspension method indicate good transparency for PVC/DBEEA. Moreover, PVC/DBEEA still has good mechanical property.

Facile Polymer of Intrinsic Microporosity-Modified Separator with Quite-Low Loading for Enhanced-Performance Lithium Metal Batteries.

Lithium metal batteries (LMBs) using Li metals as anodes are conspicuous for high-energy-density energy-storage devices. However, the nonuniform deposition of Li+ ions leading to uncontrolled Li dendrite growth, which adversely affects electrochemical performance and safety, has impeded the practical application of lithium metal batteries (LMBs). Herein, PIM-1, a type of polymer of intrinsic microporosity (PIM), was utilized for surface engineering of conventional polyolefin separators. This process resulted in the formation of a continuous and homogeneous coating across the separator, facilitating uniform Li+ ion flux and deposition, and consequently reducing dendrite formation. Notably, the loading mass was quite low (0.6 g/m2) through the convenient dipping method. The intrinsic micropores and polar groups (cyano and ether groups) of PIM-1 greatly improved the electrolyte wettability and ionic conductivity of commercial polypropylene (PP) separators. And the PIM-1 coating guided Li+ flux to achieve uniform Li deposition. Moreover, the polar groups (cyano and ether groups) of PIM-1 are beneficial to the desolvation of Li+-solvates. As a result, the synergetic effect of uniform Li+ flux, desolvation, and enhanced mechanical strength of separators brings about considerable improvement in cycle life, suppression of Li dendrite, and Coulombic efficiency for LMBs. As this surface engineering is simple, relatively low-cost, and effective, this work provides fresh insights into separators for LMBs.

Chemoselective Adsorption of Allyl Ethers on Si(001): How the Interaction between Two Functional Groups Controls the Reactivity and Final Products of a Surface Reaction.

Selective adsorption of multifunctional molecules is rarely observed when the different functional groups react via nonactivated reaction channels. Although the latter is also the case for ether cleavage and the adsorption of C=C double bonds on the highly reactive Si(001) surface, we find that allyl ethers, which combine both functional groups, react on Si(001) selectively via the cleavage of the molecules' ether group. In addition, our XPS measurements at 90, 150, and 300 K indicate an increased reactivity of the ether group when compared to monofunctional ethers. STM investigations furthermore reveal different final adsorption configurations after ether cleavage of allyl methyl ether when compared to diethyl ether as the monofunctional reference molecule. The interaction of the two functional groups in one molecule thus leads to new reaction channels with higher reactivity for ether cleavage on Si(001). As a further consequence, the reactivity of the C=C double bond is suppressed up to room temperature, leading to the observed selective adsorption.

Mechanism of Biological Transport and Transformation of Copper, Cadmium, and Zinc in Water by Chlorella

This study investigates the effectiveness of Chlorella vulgaris in treating copper, cadmium, and zinc in aqueous solutions; the aim of this study was to examine the effects of various factors on the adsorption capacity of Chlorella in water. This study explored the intra- and extracellular adsorption and accumulation patterns of copper (Cu(II)), cadmium (Cd(II)), and zinc (Zn(II)), revealing their molecular response mechanisms under the most suitable conditions. The adsorption capacity of Chlorella to Cu(II), Cd(II), and Zn(II) in water was 93.63%, 73.45%, and 85.41%, respectively. The adsorption mechanism for heavy metals is governed by both intracellular and extracellular diffusion, with intracellular absorption serving as a supplement and external uptake predominating. XRD, XPS, FTIR, SEM-EDX, and TEM-EDX analyses showed that there would be the formation of precipitates such as Cu2S, CuS2, CdS, and ZnSO4. The adsorption of Cu(II) involves its simultaneous reduction to Cu(I). Moreover, specific functional groups present on the cellular surface, such as amino, carboxyl, aldehyde, and ether groups, interact with heavy metal ions. In view of its efficient heavy metal adsorption capacity and biosafety, this study recommends Chlorella as a potential biosorbent for the bioremediation and environmental treatment of heavy metal contaminated water in the future.

Effects of Applying Biochar on Soil Cadmium Immobilisation and Cadmium Pollution Control in Lettuce (Lactuca sativa L.)

In order to analyse the impact of biochar in terms of reducing the bioavailability of cadmium (Cd) in soil, a study was conducted on the solidification effect of biochar on soil cadmium and its resistance to cadmium contamination in lettuce. In this study, soil which was contaminated with 10 mg/kg cadmium was used as the substrate; corn, rice, and wheat straw biochar were used as solidification and amendment materials; and lettuce (Lactuca sativa L. cv. Grand Rapids) was used as the test plant. The morphological characteristics of the biochar, soil pH, electrical conductivity, cation exchange capacity, and soil-available Cd, as well as lettuce plant height, fresh weight, and leaf Cd content, were measured and analysed. The results showed that all three types of biochar possessed distinct porous structures and functional groups such as hydroxyl, ether, and carbonyl groups. Increases in soil pH, electrical conductivity (EC), cation exchange capacity (CEC), lettuce plant height, and fresh weight were effectively promoted. Additionally, a significant reduction in the available Cd content in the soil and Cd content in lettuce leaves was observed, with the inhibitory effect becoming more pronounced as the biochar application rate increased. When 5% corn straw biochar was added (1 kg of substrate with 50 g of biochar), the best inhibitory effect on Cd contamination was observed, with a cadmium content of 4.63 mg/kg in lettuce leaves. The available Cd in the soil and the Cd content in lettuce leaves decreased by 32.00% and 49.78%, respectively, compared to the CK group (without biochar treatment). Additionally, the plant height and fresh weight of lettuce increased by 25.56% and 31.31%, respectively, compared to the CK group. This indicated that the application of straw biochar can stabilise soil Cd, reduce the availability of Cd in the soil, inhibit the transfer of Cd into lettuce, promote the growth of lettuce, and lower the ecological environmental risk of Cd. These research results can provide a theoretical basis and scientific guidance for the remediation of soil Cd contamination and the safe production of lettuce.

Characteristics and mechanism of low-temperature NO adsorption by activated carbon

Activated carbon is widely used to purify flue gas in industries like steel and metallurgy, but its ability to adsorb NOx at medium to low flue gas temperatures is limited. This study conducted adsorption experiments in different atmospheres within −20 to 30 °C. As the temperature decreased from 30 °C to −20 °C, the NOx adsorption amount was increased by 4.61 times. Lowering temperature greatly promoted NOx adsorption. Temperature-programmed desorption experiments determined the amount of NOx adsorbed through physical adsorption and chemical adsorption. As the temperature decreased from 30 °C to −20 °C, the proportion of physically adsorbed NOx to total adsorption amount increased from 2.9 % to 45.5 %, and the proportion of physically adsorbed NO2 to total physical adsorption amount increased from 0 to71.6 %. Lowering the temperature benefited NO oxidation and NO2′s adsorption on activated carbon. Desorption curves of chemically adsorbed NOx indicated that a decrease in temperature does not affect the chemical adsorption pathways of NOx. Physical adsorption of NOx was studied by density functional theory calculations. NO2 has much stronger physical adsorption than NO and can physically adsorb near saturated carbon atoms, carbonyl groups, ether groups, hydroxyl groups, and lactone groups. At low temperatures, NO is first oxidized to NO2 on activated carbon and then NO2 is adsorbed through both physical and chemical pathways. Modifying the surface of activated carbon to increase hydroxyl, ether, and lactone groups can help enhance its performance of low-temperature NOx adsorption.

Synthetic Modification and Insecticidal Activity of 4-epi-cis-Dihydroagarofuran Derivatives.

To synthesize the fundamental framework of dihydroagarofuran, a novel strategy was devised for constructing the C-ring through a dearomatization reaction using 6-methoxy-1-tetralone as the initial substrate. Subsequently, the dihydroagarofuran skeleton was assembled via two consecutive Michael addition reactions. The conjugated diene and trans-dihydroagarofuran skeleton were modified. The insecticidal activities of 33 compounds against Mythimna separata were evaluated. Compounds 11-5 exhibited an LC50 value of 0.378 mg/mL. The activity exhibited a remarkable 29-fold increase compared to positive control Celangulin V, which was widely recognized as the most renowned natural dihydroagarofuran polyol ester insecticidal active compound. Docking experiments between synthetic compounds and target proteins revealed the shared binding sites with Celangulin V. Structure-activity relationship studies indicated that methyl groups at positions C4 and C10 significantly improved insecticidal activity, while ether groups with linear chains displayed enhanced activity; in particular, the allyl ether group demonstrated optimal efficacy. Furthermore, a three-dimensional quantitative structure-activity relationship model was established to investigate the correlation between the skeletal structure and activity. These research findings provide valuable insights for discovering and developing dihydroagarofuran-like compounds.

Synthesis of proton-conductive Perfluoro(Benzylphosphonic Acid)s via polymer side chain phosphorylation

Nafion™ utilizes -SO3H groups for proton conduction. Using an alternative proton-exchange functionality like -PO3H2, -COOH, etc., to replace -SO3H in ion conductive fluoropolymers has attracted significant attention. For example, composite membranes comprising Nafion™ and perfluoro(carboxylic acid) bearing a -COOH group on its side chains have been used in color-alkali cells to reduce unwanted electrolyte crossovers. In the present paper, we reported a new synthetic strategy for constructing novel -PO3H2-bearing fluoropolymers (FBP). Our method employs a ZnI2-promoted phosphorylation reaction of triethyl phosphite that converts benzyl alcohol on a side chain of a fluoropolymer into a benzylphosphodiester group, followed by trimethylsilyl chloride (TMSCl) hydrolysis to yield FBP. This strategy has enabled us to graft a fluoropolymer side chain directly with phosphonic acid. Although the in-plane proton conductivities of FBP fluoropolymers are lower than those of Nafion™ 115, most FBPs, especially Homo-FBP that has no fluoroalkyl ether group on its side chains, are significantly more stable against hydroxyl radical degradations in Fenton tests. This paper presents a new method for the synthesis of -PO3H2-containing fluoropolymers and our work also confirms a novel strategy for enhancing the long-term stability of a proton-conductive fluoropolymer in electrical devices—eliminating or reducing fluoroalkyl ether groups on the side chains of the polymer.

Utilization of Adsorbent Based on Rice Straw (&lt;i&gt;Oryza sativa&lt;/i&gt;) for Cr(VI) Ions Reduction in Aqueous Solutions

In this study, we utilized an adsorbent based on rice straw for reducing hexavalent chromium ions (Cr (VI)) in an aqueous solution. The rice straw as adsorbent raw material was washed, dried, and powdered. Rice straw powder was heated at 450°C for 2 hours to obtain rice straw adsorbent. The adsorbent was activated with 1M H3PO4 for 4 hours. Characterization of the adsorbent was done using Fourier Transform Infra-Red (FTIR) method. FTIR spectra showed the presence of hydroxy, carboxylic, aromatic, and ether groups on the surface of the rice straw and the made adsorbent. The reduction of Cr (VI) ions in aqueous solutions was carried out using the adsorption batch method. The adsorption process was conducted in various the Cr (VI) solutions pH for 1-5 and variations in contact time for 5-720 minutes. The highest percentage reduction of Cr (VI) reached 66.90%. It has occurred at pH 2 and equilibrium at 600 minutes of contact time.

Modification of a Carboxymethyl Cellulose/Poly(vinyl alcohol) Hydrogel Film with Citric Acid and Glutaraldehyde Crosslink Agents to Enhance the Anti-Inflammatory Effectiveness of Triamcinolone Acetonide in Wound Healing.

Anti-inflammatory wound healing involves targeted drug delivery to the wound site using hydrogel materials to prolong drug effectiveness. In this work, hydrogel films were fabricated using carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) crosslinked with citric acid (CA) and glutaraldehyde (GA) at different concentrations. The crosslinker densities were optimized with various CA (2-10% w/v) and GA (1-5% v/v) concentrations. The optimized crosslink densities in the hydrogel exhibited additional functional group peaks in the FT-IR spectra at 1740 cm-1 for the C=O stretching of the ester linkage in CA and at 1060 cm-1 for the C-O-C stretching of the ether group in GA. Significantly, the internal porous structures of hydrogel composite films improved density, swelling capacities, solubility percentage reduction, and decreased water retention capacities with optimized crosslinker densities. Therefore, these hydrogel composite films were utilized as drug carriers for controlled drug release within 24 h during medical treatment. Moreover, the hydrogel films demonstrated increased triamcinolone acetonide (TAA) absorption with higher crosslinker density, resulting in delayed drug release and improved TAA efficiency in anti-inflammatory activity. As a result, the modified hydrogel showed the capability of being an alternative material with enhanced anti-inflammatory efficiency with hydrogel films.

Polymerization-induced self-assembly amino acid ionic liquid/poly(ethylene oxide) thin-film composite membranes for CO2 separation

It is well known that crosslinking poly(ethylene oxide) (PEO) membranes exhibit high CO2/N2 solubility selectivity, and are suitable for separating CO2 from flue gas. However, the high CO2/N2 selectivity is temperature sensitive and decreases rapidly with increasing temperature. To overcome this deficiency, imidazolium-based amino acid ionic liquids (AAILs) are introduced into the PEO membranes. A series of (AAILs-PEO)/PAN thin-film composite (TFC) membranes were prepared by a polymerization-induced self-assembly process. Due to the hydrogen and Coulomb interactions between the imidazolium ring of AAILs and the ether groups of PEO monomers, the morphology of the selective layer changed from micellar to granular upon the introduction of the AAILs into the PEO membranes, while the chain-segment flexibility and interspacing of the PEO are also changed. Compared with the original PEO/PAN TFC membrane, the (AAILs-PEO)/PAN TFC membranes show much higher CO2/N2 selectivity, which increases from ∼41 to ∼ 74. In addition, the AAILs show strong hydrophilicity, which leads to a significant increase in CO2/N2 selectivity under the wet-gas feed, reaching ∼105. Compared with the original PEO/PAN TFC membranes with CO2/N2 selectivity of ∼10 at 70 °C, the (AAILs-PEO)/PAN TFC membranes show the selectivity of ∼30, coupled with CO2 permeance of ∼1300 GPU at 70 °C. Under the 40: 60 mixtures of CO2: N2, which is a common lime kiln exhaust gas, by using the (AAILs-PEO)/PAN TFC membrane, the CO2 concentration on the downstream side can reach over 90 % at 20 °C and over 70 % at 70 °C, respectively, under a pressure ratio of 5.

Porous bi-functional ionic liquid-grafted metal–organic framework for diluted CO2 cycloaddition reaction

Direct utilization of low-concentration CO2 is of importance to mitigate the global warming and reduce energy consumption. Herein, a new bi-functional ionic liquid-grafted material was fabricated for CO2/N2 selectivity and diluted CO2 cycloaddition reaction. Following the preparation of 1-carboxymethyl-3-methoxy ethyl-imidazolium chloride ([CmMOEim]Cl) containing carboxyl and ether group, MIL-53(Al) was used for directly chemical grafting of the ionic liquid to obtain [CmMOEim]Cl@MIL-53(Al). CO2 capture capacity of [CmMOEim]Cl@MIL-53(Al) reached up to 70 cm3 CO2/g sorbent at 25 °C and 0.1 MPa, which was higher than that of two individual components. Cyclopropyl carbonate of 97 % yield was obtained at 110 °C, 3 MPa of initial 50 vol% CO2/N2 pressure and 4 h with 2.4 wt% [CmMOEim]Cl@MIL-53(Al)-0.4 under solventless and co-catalyst-free condition. Various terminal cyclocarbonates were synthesized with above 90 % yield. In addition, the heterogeneous catalyst was separated from reaction system by simple centrifugation and the yield of cyclopropyl carbonate was higher than 90 % after 12 cycles owing to the chemical grafting of [CmMOEim]Cl on MIL-53(Al).

Plasmalogen oxidation induces the generation of excited molecules and electrophilic lipid species.

Plasmalogens are glycerophospholipids with a vinyl ether linkage at the sn-1 position of the glycerol backbone. Despite being suggested as antioxidants due to the high reactivity of their vinyl ether groups with reactive oxygen species, our study reveals the generation of subsequent reactive oxygen and electrophilic lipid species from oxidized plasmalogen intermediates. By conducting a comprehensive analysis of the oxidation products by liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS), we demonstrate that singlet molecular oxygen [O2 (1Δg)] reacts with the vinyl ether bond, producing hydroperoxyacetal as a major primary product (97%) together with minor quantities of dioxetane (3%). Furthermore, we show that these primary oxidized intermediates are capable of further generating reactive species including excited triplet carbonyls and O2 (1Δg) as well as electrophilic phospholipid and fatty aldehyde species as secondary reaction products. The generation of excited triplet carbonyls from dioxetane thermal decomposition was confirmed by light emission measurements in the visible region using dibromoanthracene as a triplet enhancer. Moreover, O2 (1Δg) generation from dioxetane and hydroperoxyacetal was evidenced by detection of near-infrared light emission at 1,270 nm and chemical trapping experiments. Additionally, we have thoroughly characterized alpha-beta unsaturated phospholipid and fatty aldehydes by LC-HRMS analysis using two probes that specifically react with aldehydes and alpha-beta unsaturated carbonyls. Overall, our findings demonstrate the generation of excited molecules and electrophilic lipid species from oxidized plasmalogen species unveiling the potential prooxidant nature of plasmalogen-oxidized products.