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Sustainable development based on the value-added utilization of furfural residues (FRs) is an effective way to achieve a profitable circular economy. This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors (SCs). To improve the electrochemical performance of FR-based carbon materials, a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed. More defects could be obtained after methanol treatment, which is incline to optimize textural structure. The activated methanol treated FR-based carbon materials (AFRMs) possess high specific surface area (1753.5 m2 g−1), large pore volume (0.85 cm3 g−1), interconnected micro/mesoporous structure, which endow the AFRMs with good electrochemical performance in half-cell (326.1 F g−1 at 0.1 A g−1, 189.4 F g−1 at 50 A g−1 in 6 M KOH). The constructed symmetric SCs based on KOH, KOH–K3Fe(CN)6 and KOH-KI electrolyte deliver energy density up to 8.9, 9.9 and 10.6 Wh kg−1 with a capacitance retention of over 86% after 10,000 cycles. Furthermore, the self-discharge can be restrained by the addition of K3Fe(CN)6 and KI in KOH electrolyte. This study provides an effective approach for high-valued utilization of FR waste.

Coal chemical wastewater (CCW) with the features of high toxicity and poor biodegradability is a big issue in environmental remediation, posing a great threat to aquatic ecosystems and to human beings. Such complex molecular mixtures are notoriously difficult to characterize without initial physical separation. Herein, we present the 3D diffusion ordered spectroscopy (DOSY) analysis for CCW using DOSY-COSY and DOSY-HSQC methods, the advantages of this strategy have been demonstrated in the analysis of mixtures of aliphatic oxygenates and aromatic compounds, before being implemented on a genuine CCW sample in this study. The results showed that 3D DOSY is a robust and reliable tool for providing superior resolution and virtual separation of complex pollutants, and can be used as a general approach for structural elucidation.

Poly-p-phenylene terephthamide (PPTA) is widely applied in bulletproof products and composite materials because of its high strength, high modulus, high temperature resistance and creep resistance. The PPTA molecule with highly symmetrical and regular structure is linear structure formed by the alternating connection of benzene ring and amide bond, and the amide bonds between the molecular chains form strong hydrogen bonds. Therefore, the dissolution and depolymerization of PPTA is very challenging. In this work, an efficient catalytic system was developed for the controllable degradation of waste PPTA, and the high-value added monomers terephthalic acid (TPA) and p-phenylenediamine (PPD) were recovered. The results show that the amide bonds of PPTA can be selectively cleaved by the strong Bronsted base catalysts in alcohols, especially in the NaOH/n-butanol system. Under the optimal degradation conditions (5 wt% NaOH in n-butanol, 180 °C, 6 h), the percentage degradation of PPTA is 100%, and the yields of TPA and PPD are 92.0% and 91.5%, respectively. In addition, it is found that the wettability of n-alcohols on PPTA monofilament and the addition of a small amount of water have important influences on the degradation of PPTA. The work elucidates the degradation mechanism of PPTA, and reveals the important factors affecting the depolymerization of PPTA.

As the frontier in heterogeneous catalyst, a monomer and positively charged active sites in the single-atom catalyst (SAC), anchored by high electronegative N, O, S, P, etc., atoms, may not be active for the multispecies (O2, substrates, intermediates, solvent etc.) involved liquid-phase aerobic oxidation. Here, with catalytic, aerobic oxidation of 5-hydroxymethylfurfural as an example, Pt SAC (Pt1-N4) was synthesized and tested first. With commercial Pt/C (Pt loading of 5 wt %) as a benchmark, 2,5-furandicarboxylic acid (FDCA) yield of 97.6% was obtained. Pt SAC (0.56 wt %) gave a much lower FDCA yield (28.8%). By changing the coordination atoms from highly electronegative N to low electronegative Co atoms, the prepared Pt single-atom alloy (SAA, Pt1-Co3) catalyst with ultralow Pt loading (0.06 wt %) gave a much high FDCA yield (99.6%). Density functional theory (DFT) calculations indicated that positively charged Pt sites (+0.712e) in Pt1-N4 almost lost the capability for oxygen adsorption and activation, as well as the adsorption for the key intermediate. In Pt1-Co3 SAA, the central negatively charged Pt atom (-0.446e) facilitated the adsorption of the key intermediate; meanwhile, the nearby Co atoms around the Pt atom constituted the O2-preferred adsorption/activation sites. This work shows the difference between the SAC with NPs and the SAA during liquid-phase oxidation of HMF and gives a useful guide in the future single-atom catalyst design in other related reactions.

The acidity and basicity of the solvents can influence the reaction outcome notably, and hence the precise measurement of pH is important for reaction. However, not all the pH values of organic solvents can be determined with a classic pH meter straightly. In this research, the acidity and basicity of environmentally friendly green solvents, such as ZnCl2 molten salt hydrate, ionic liquids (ILs) and deep eutectic solvents (DESs), were characterized by 31P and 1H NMR spectroscopy using trimethylphosphine oxide (TMPO) and pyrrole as probe molecules at 298 K. For the ZnCl2 molten salt hydrate, the acidic strength of the ZnCl2 molten salt hydrate increased with the concentration of ZnCl2. By using the 1H-pyrrole NMR approach, it was found that the base strength of amino acid-based ILs follows the order: [Ch][Lys] > [Ch][His].

Ternary deep eutectic solvents (TDESs) comprising choline chloride (ChCl), glycerol and l -arginine were synthesized as catalysts and solvents for the conversion of d -glucosamine (GlcNH2) into deoxyfructosazine (DOF). The interactions between these three components in the prepared TDESs were studied by 1H-, 35Cl-NMR spectra and 1H diffusion-ordered spectroscopy (DOSY) measurements. The chemical shift changes of active hydrogen in the 1H-NMR spectra of TDES system and widening of signals in the 35Cl-NMR spectra confirmed the hydrogen bonding interaction between the components, which was further supported by the decrease of diffusion coefficients (D) of the TDES components according to 1H DOSY measurements. The influences of reaction temperature and l -arginine content in the TDESs on the yield of DOF were also studied. The experimental results have shown that when the molar ratio of ChCl, glycerol, and l -arginine was 1:2:0.1, DOF was the major product with a yield of 22.6% at 90 °C for 120 min. The chemical shift titration indicated that the carboxyl group of l -arginine in the TDES is the catalytical active site, so the mechanism of the catalytic reaction between GlcNH2 and the TDES was proposed. Moreover, a reaction intermediate, dihydrofructosazine, was identified in the self-condensation reaction of GlcNH2 by an in situ 1H NMR technique.

The wide application of melamine–formaldehyde resins (MFRs) in the food industry aggravates plastic pollution problems. Recycling of the waste MFRs remains a big challenge due to its compact structure. Herein, a high MFR degradation ratio of ca. 84 wt% was achieved under mild conditions (180 °C) in a methanesulfonic acid (MSA)–tetrahydrofuran (THF)–H2O system with cyanuric acid as the main degradation product. The SEM results showed that the degradation of MFRs followed different reaction mechanisms when H2O and THF were applied as solvents, respectively. The combination of the two solvents showed an obvious synergistic effect for the degradation of MFRs. The degradation experimental results with melamine as the model intermediate indicated that the degradation of MFRs proceeded via the selective cleavage of the sp2C–sp3N and sp3C–sp3N bonds to recover valuable C and N alternated-aromatic ring (CNAR) units, followed by their transformation into a valuable chemical of cyanuric acid.

A series of poly(ionic liquid)s (PILs) based on 1-vinyl-3-(3-sulfopropyl)imidazolium (VSpIm) and sodium p-styrenesulfonate (NaSS) have been successfully synthesized and fully characterized. The swelling behaviours of the PILs in 18 solvents with a wide range of Hansen solubility parameters (δT) were investigated. The PILs exhibited distinct swelling properties in solvents with δT > 24.5 MPa1/2, such as water, formamide and methanol. The molar swelling ratio (QM), which represented the swelling ability of the PILs in solvent, was linearly positively correlated with the δT value. Moreover, the enrichment behaviours of the PILs in various mixed solvents were also studied. In water/solvent and formamide/solvent monophasic mixed solvents, the enrichment factors of the PILs to water and formamide were up to 39.82 (water/THF) and 17.69 (formamide/THF), respectively. The enrichment factor of the PILs to water (or formamide) was linearly positively correlated with the difference between δT (water) (or δT (formamide)) and δT (solvent). The excellent swelling and enrichment properties of the PILs in solvents were attributed to the strong interactions between the PILs and solvent molecules, especially the hydrogen-bonding interactions, which was supported by nuclear magnetic resonance (NMR) spectroscopy. Furthermore, a PIL was used as a catalyst for the hydration of alkyne and found that it had higher catalytic activity than those of both heterogeneous and homogeneous catalysts.

Placentation is a major determinant of the success of pregnancy. It is regulated by several factors such as cell adhesion molecules, tight junctions, and gap junctions. The cell adhesion molecules are integrins, cadherins, immunoglobulins, nectins, and selectins. The tight junctions are composed of claudins, occludin, and junction adhesion molecule proteins while the gap junctions are composed of connexins of varying molecular weights. During placentation, some of these molecules regulate trophoblast proliferation, trophoblast fusion, trophoblast migration, trophoblast invasion, trophoblast-endothelium adhesion, glandular remodeling, and spiral artery remodeling. There is a dysregulated placental expression of some of these molecules during obstetric complications. We have, hereby, indicated the expression patterns of the subunits of each of these molecules in the various trophoblast subtypes and in the decidua, and have highlighted their involvement in physiological and pathological placentation. The available evidence points to the relevance of these molecules as distinguishing markers of the various trophoblast lineages and as potential therapeutic targets in the management of malplacentation-mediated diseases.

Fischer-Tropsch (F-T) process is an important synthesis route to acquire clean liquid fuels through modern coal chemical industry, which converts syngas (CO and H2) into hydrocarbon, and also generates oxygenates discharged as the F-T waste-water. These oxygen-containing compounds in F-T waste-water have the similar molecular weight and some are even isomers of each other. Hence, it is necessary to develop rapid and efficient analysis tools to obtain identification and quantitative information of the F-T waste-water. The pure shift NMR techniques provided only chemical shift information in one-dimension 1H NMR spectra, without homonuclear JH-H coupling. In this work, we tested and compared three pure shift NMR techniques (including Zangger-Sterk, PSYCHE and TSE-PSYCHE methods) in the analysis of two F-T waste-water model mixtures, genuine waste-water and two alcohol isomer mixtures. The results show that JH-H coupling multiplicities are collapsed into singlets corresponding to individual chemically distinct protons of the compound. For some severely overlapped signals in the pure shift NMR spectra, the chemical shift selective filters with TOCSY (CSSF-TOCSY) experiments were conducted to assist the signal assignment. Thus, pure shift NMR approaches can identify most signals of components, and CSSF-TOCSY can extract the signal of a specific compound. The combination of these two NMR techniques offers a powerful tool to analyze the F-T waste-water or other complex mixtures including isomer mixtures.

The actin cytoskeleton is extremely dynamic and supports diverse cellular functions in many physiological and pathological processes, including tumorigenesis. However, the mechanisms that regulate the actin-related protein 2/3 (ARP2/3) complex and thereby promote actin polymerization and organization in cancer cells are not well-understood. We previously implicated the proline-rich 11 (PRR11) protein in lung cancer development. In this study, using immunofluorescence staining, actin polymerization assays, and siRNA-mediated gene silencing, we uncovered that cytoplasmic PRR11 is involved in F-actin polymerization and organization. We found that dysregulation of PRR11 expression results in F-actin rearrangement and nuclear instability in non-small cell lung cancer cells. Results from molecular mechanistic experiments indicated that PRR11 associates with and recruits the ARP2/3 complex, facilitates F-actin polymerization, and thereby disrupts the F-actin cytoskeleton, leading to abnormal nuclear lamina assembly and chromatin reorganization. Inhibition of the ARP2/3 complex activity abolished irregular F-actin polymerization, lamina assembly, and chromatin reorganization due to PRR11 overexpression. Notably, experiments with truncated PRR11 variants revealed that PRR11 regulates F-actin through different regions. We found that deletion of either the N or C terminus of PRR11 abrogates its effects on F-actin polymerization and nuclear instability and that deletion of amino acid residues 100–184 or 100–200 strongly induces an F-actin structure called the actin comet tail, not observed with WT PRR11. Our findings indicate that cytoplasmic PRR11 plays an essential role in regulating F-actin assembly and nuclear stability by recruiting the ARP2/3 complex in human non-small cell lung carcinoma cells.

Despite being used as an anti-leukemic drug, the poor solubility of 6-mercaptopurine (6-MP) limits its use in topical and parenteral applications. Dendrimers are commonly used as drug carriers to improve their solubility in aqueous solution. In this work, the interactions between 6-MP and the amine-terminated poly(amidoamine) dendrimers (PAMAM-NH2 ) were investigated by various NMR technology. The chemical shift titrations disclosed that the 6-MP interacted with the surface of PAMAM-NH2 mainly through electrostatics. The determination of diffusion coefficient and relaxation measurements further confirmed the presence of interactions in 6-MP/PAMAM-NH2 complexes. In addition, the encapsulation of 6-MP within the cavity of PAMAM-NH2 was revealed through nuclear Overhauser effect spectroscopy and Saturation Transfer Double Difference analysis. Finally, the binding strength (H-8 is 100% and H-2 is 70%) of 6-MP to PAMAM-NH2 was quantitatively expressed using epitope maps. This study provides a systematic methodology for qualitative and quantitative studies of the interactions between dendrimers and drug molecules in general.

Deep eutectic solvents (DESs) have attracted considerable attention due to their unique properties. Owing to similar structures and properties, DESs are also called "quasi-ionic liquids" or "ionic liquid analogous". However, for a deeper understanding and application of DESs, a comprehensive investigation on the ionicity of DESs is crucial. In this work, the effects of the structure and components of typical DESs on the ionicity were investigated. Moreover, the ionicity was discussed by using Walden plot, and the validity of applying it to DESs was verified using pulsed field gradient nuclear magnetic resonance (PFG-NMR). We found that the lack of free charged species and high viscosities make it difficult to achieve optimal conductivities for DESs, and thus most of them exhibit "poor ionic" nature. Fortunately, with an in-depth understanding of its microstructure and physicochemical properties, the properties of DESs can be finely tailored by selecting or even designing suitable parent compounds for functional applications. In particular, the ionicity of Li-based DESs was investigated for their potential application as electrolytes in Li-ion batteries.

The existing triacetylglycerol (TAG) production method involves esterification of oil (fat)-derived glycerol with acetic acid, forming a mixture of mono-, di- and tri- acetylglycerols. Herein, a new acyl exchange reaction is developed to directly and efficiently produce TAG from waste oils and fats by the driving effect of substituent size changes. Small-sized acetic acids easily replace large long-chain fatty acids of oils. This release in the intramolecular tension and diminishing of steric hindrance make TAG both thermodynamically and dynamically the most favorable product. Pure TAG was obtained with a high yield of 94.9%.

Hydrogen production by steam reforming of ethylene glycol (EG) at 300 °C was investigated over SiO2 and CeO2 supported Pt–Ni bimetallic catalysts prepared by incipient wetness impregnation methods. It was observed that impregnation sequence of Pt and Ni can affect the performance of catalysts apparently. Catalyst with Pt first and then Ni addition showed higher EG conversion and H2 yield owing to the Ni enrichment on the surface and the proper interaction between Pt and Ni. It was observed that although SiO2 supported catalysts exhibited better activity and H2 selectivity, CeO2 supported ones had better stability. This is attributed to the less coke formation on CeO2. Increasing Pt/Ni ratio enhanced the reaction activity, and Pt3–Ni7 catalysts with 3 wt% Pt and 7 wt% Ni showed the highest activity and stability. Ni surficial enrichment facilitated the C—C bond rupture and water gas shift reactions; and Pt addition inhibited methanation reaction. Electron transfer and hydrogen spillover from Pt to Ni suppressed carbon deposition. These combined effects lead to the excellent performance of Pt3–Ni7 supported catalysts. Keywords: Ethylene glycol, Steam reforming, Pt–Ni bimetallic catalyst, Hydrogen production, Synergistic effect

Perfluorooctanoic acid (PFOA) is a persistent environmental contaminant with serious negative health effects, and removal of it from water is therefore highly relevant for environmental safety. In this paper, poly(amidoamine) (PAMAM) dendrimers have been proposed as hosts for the PFOA in order to remove it from aqueous solutions. The different aggregate structures for PAMAM-PFOA complexes with increase of −COO−/−NH3+ molar ratios were proposed on the basis NMR titrations using 19F NMR and further analyzed by the relaxation and diffusion measurements. It is suggested that PFOA micelles are transferred to the bilayer with increasing PAMAM concentration. Moreover, the protonated surface amine groups of PAMAM contribute to reduce the critical aggregation concentration (CAC) of PFOA. The study shows that the main driving force for interaction between PAMAM and PFOA is ionic interaction. This research will serve as a starting-point for removing the fluorinated contamination by using PAMAM dendrimers.

Epitaxy crystalline structure and multilayer alternated structure can both improve the toughness. In this work, these two structures are simultaneously introduced into one iPP/HDPE blend sample by a self-designed multi-flow vibration injection molding (MFVIM) device. As a result, there is a synergistic influence on enhancing the impact strength. The impact strength of this sample reaches to 76.04 kJ/m2, which is much higher than the sample fabricated by conventional injection molding, 3.27 kJ/m2. The characterization of crystalline structure and macroscopic hierarchical structure is carried out by PLM, SEM, SAXS, WAXD and DSC. It is found that these two structures cause an associated deformation by providing various paths of external force and prolonging its transmitted path during fast impact loading. These results provide a novel method to enhance the toughness of polymer material by toughening it from different scales.

Many experimental results have revealed that the re‐entanglement kinetics of disentangled polymers is much slower than that predicted by tube theory. This retarded recovery of fully entangled state is of practical significance that shear‐induced modification may offer a way to improve processability for a polymer by reducing viscosity. This work tried to figure out the shear‐rate dependence variation of viscosity in the view of evolution of entanglement state through disentanglement and re‐entanglement, aiming to provide fundamental insights into application prospect of shear‐induced modification in preparing “in‐pellet” disentangled polymers prior to final processing. High‐density polyethylene was sheared on a parallel‐plate rotational rheometer with a linearly increased shear rate. Results showed that higher shear rate could induce further disentanglement, resulting in a lower viscosity with a reduction rate up to 93.7%, larger molecular weight between entanglements Mₑ, and longer re‐entanglement time. Additionally, less entanglement would give a larger lamellar thickness of sheared samples after nonisothermal crystallization. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 598–606

Ethylparaben (EtP) and propylparaben (PrP) are common preservatives and well-known endocrine-disrupting chemicals. Studies have demonstrated that they can reduce female fertility, but the underlying mechanism, especially that on embryo implantation, is still poorly understood. Endometrial decidualization is a critical event for embryo implantation. In this study, we aimed to explore the effects of EtP/PrP on endometrial decidualization. Pregnant mice were dosed daily by oral gavage with EtP at 0, 400, 800 and 1600 mg/kg or with PrP at 0, 625, 1250 and 2500 mg/kg from Day 1 of pregnancy until sacrifice. The results showed that the rate of pregnant mice with impaired embryo implantation, whose number of implantation sites was less than 7, was significantly increased after exposure to 1600 mg/kg EtP or 2500 mg/kg PrP. Further study found that the expression of endometrial decidualization markers HOXA10, MMP9 and PR was significantly downregulated in 1600 mg/kg EtP group and 2500 mg/kg PrP group. Notably, serum oestrogen and progesterone levels were significantly increased, whereas the expression of uterine oestrogen receptor and progesterone receptor was decreased following 1600 mg/kg EtP or 2500 mg/kg PrP exposure. In the breeding test, fewer offspring were found after females were exposed to 1600 mg/kg EtP or 2500 mg/kg PrP in early pregnancy. This demonstrated that exposure to EtP/PrP interfered with embryo implantation by compromising endometrial decidualization in early-stage pregnant mice. Disorders of reproductive hormones and hormone receptor signals could be responsible for impaired decidualization. This study broadened the understanding on the biological safety of EtP and PrP.

The isomerization of d-glucose to d-fructose plays a key role in the biochemical and chemical conversion of biomass, and it is therefore desirable to develop and improve catalysts for this reaction. In this study, the environmentally friendly polymer poly(amidoamine) (PAMAM) dendrimer's properties as catalysts for this isomerization are investigated. The experimental results showed that the PAMAM dendrimers, which have basic terminal groups, can effectively promote the d-glucose isomerization reaction. Under the optimized reaction conditions, d-fructose was generated with a 20% maximum yield and above 90% selectivity. 13C and 2H isotope experiments by NMR were carried out to explore the reaction mechanism. When the reaction was performed in D2O, the C1 signal of d-fructose changed to a triplet, which confirmed that the C1 carbon binds to a deuterium atom, i.e., isotopic exchange. It was also found that the deuterium atom at the C2 position of d-glucose-2-d1 cannot transfer to d-fructose. These data indicate that PAMAM dendrimers catalyze d-glucose isomerization through a mechanism, which includes deprotonation, formation of ene-diol intermediate, and proton exchange with the solvent.

Using environment-friendly catalysts to convert biomass into compounds with high values is one of the central topics of green chemistry. In this work, [Ch][Pro] (cholinium as the cation and l-proline as the anion) ionic liquid was synthesized and applied as a model catalyst in the production of deoxyfructosazine (DOF) and fructosazine (FZ) from d-glucosamine (GlcNH2). The 13C NMR chemical shift titration experiments and the diffusion-ordered NMR spectroscopy (DOSY) measurements showed that, when the [Ch][Pro] interacted with GlcNH2, the l-proline anion ([Pro]-) played a major catalytic role instead of cholinium cation ([Ch]+). The effects of the reaction temperature and the amount of [Ch][Pro] on the product yields were surveyed. The experimental results showed that the highest DOF yield (33.78%) was obtained after 30 min at 100 °C when the molar ratio of [Ch][Pro]/GlcNH2 was 1. Moreover, in situ 1H NMR and in situ 13C NMR experiments were applied to monitor the reaction process with [Ch][Pro] as the catalyst. The reactive intermediate, dihydrofructosazine, was clearly detected by these in situ techniques. Accordingly, a possible reaction pathway was proposed. By applying other amino acids as the anions, we also prepared five other [Ch][AA] ionic liquids, and they showed different catalytic activities and selectivity in the GlcNH2 self-condensation reaction.

Exposure to ethephon (ETH), a plant growth regulator commonly used for several purposes, can potentially decrease sperm numbers and viability. Occasional findings regarding ETH effects on female reproduction during early pregnancy have also been reported. During early pregnancy, endometrial decidualization is a critical event for embryo implantation and pregnancy maintenance. Thus, we aimed to explore the effect and mechanism of ETH on endometrial decidualization both in vivo and in vitro. Mice were gavaged with 0 and 285 mg/kg b.w. ETH from gestational days (GD)1 until sacrifice, whereas pseudopregnant mice from pseudopregnant day 1 (PPD-1) until PPD-8. Primary mouse endometrial stromal cells (mESCs) received 640 ug/ml ETH and added E2 and P4 to induce decidualization. Results indicated female albino CD1 mice exposed to high dose of ETH (285 mg/kg b.w.) by oral gavage, the number of embryo implantation sites on GD6 and GD8 were significantly decreased, the levels of serum E2 and P4 on GD8 were significantly decreased. Compared with the control group, the decidualization response artificially induced by corn oil in pseudopregnant mice and by E2 and P4 in primary mouse endometrial stromal cells (mESCs) was weakened in the high dose of ETH treated group. The high dose, 285 mg/kg b.w ETH treated group altered the expression of endometrial decidual markers on GD6 and GD8. The triglyceride and fatty acid metabolism-related genes were significantly increased after female albino CD1 mice exposed to high does, 285 mg/kg b.w ETH on GD6 and GD8. GPR120 was substantially reduced after ETH treatment. When overexpression of GPR120, the compromised decidualization induced by ETH treatment was rescued. Furthermore, molecular docking presented Thr234 and His251 of GPR120 as preferred binding sites for ETH. Mutation of these two sites rescued the compromised decidualization induced by ETH. In conclusion, we demonstrated that ETH exposure could impair decidualization during early pregnancy. GPR120 expression and binding between GPR120 and ETH are crucial for impaired decidualization mediated via ETH.

Butylated hydroxytoluene (BHT), one of the most widely used synthetic phenolic antioxidants, is a popular food additive. Previous studies have reported the possible health hazards of BHT. However, BHT effects on female reproduction, especially on endometrial decidualization, are still unknown. During early pregnancy, decidualization plays important roles for embryo implantation and pregnancy establishment. This study aimed to explore the effects of BHT on endometrial decidualization in pregnant mice. The pregnant mice received BHT via intraperitoneal injection at doses of 0, 200, and 400 mg/kg/day from day 1 (D1) of pregnancy until sacrifice. Under BHT exposure, maternal body weight was significantly decreased during early pregnancy. Compared with the control group, the number of implantation sites and uterine weight were significantly reduced in the BHT groups. The uterine lumen failed to close after BHT exposure, and the decidual morphology of endometrial stromal cells was inhibited by BHT. Furthermore, BHT significantly decreased the expression of endometrial decidual markers including COX2, HOXA10, and MMP9. Notably, the levels of serum estrogen (E2) and progesterone (P4) and expression levels of uterus estrogen receptor α (ERα) and progesterone receptor (PR) during early pregnancy were significantly upregulated following BHT exposure. In conclusion, these results demonstrated that gestational BHT exposure could inhibit decidualization of mouse endometrium during early pregnancy. The disorders of reproductive hormones and changes of hormone receptor signals could be responsible for the impaired decidualization. This study provided new evidence for the deleterious effects of BHT on female reproduction and revealed the potential reproductive toxicity of synthetic phenolic antioxidants.

Benzo(a)pyrene (B(a)P) is a widespread persistent organic pollutant (POP) and a well-known endocrine disruptor. Exposure to BaP is known to disrupt the steroid balance and impair embryo implantation, but the mechanism under it remains unclear. The corpus luteum (CL), the primary source of progesterone during early pregnancy, plays a pivotal role in embryo implantation and pregnancy maintenance. The inappropriate luteal function may result in implantation failure and spontaneous abortions. Therefore, this study was conducted to assess the effects and potential mechanisms of B(a)P on the CL function. Our results showed that pregnant mice received B(a)P displayed impaired embryo implantation and dysfunction of ovarian CL. The estrogen and progesterone levels decreased by B(a)P. In vitro, exposure to BPDE, which is the metabolite of B(a)P, affected the luteinization of granular cell KK-1. Additionally, melatonin and its receptors, which are important for ovarian function and anti-oxidative damage, were affected by B(a)P or BPDE. B(a)P or BPDE-treated alone impaired antioxidant capacity of ovarian granulosa cells, caused an increasing of ROS and cell apoptosis, and disrupted the PI3K/AKT/GSK3β signaling pathway in vivo and in vitro. Co-treatment with melatonin alleviated B(a)P or BPDE-induced CL dysfunction by ameliorating oxidative stress, counteracting phosphorylation of PI3K/AKT/GSK3β signaling pathway, decreasing the apoptosis of the ovarian cells. Moreover, activation of the melatonin receptor by ramelteon in KK-1 cells exhibits an analogous protective effect as melatonin. In conclusion, our findings not only firstly clarify the potential mechanisms of BaP-induced CL dysfunction, but also extend the understanding about the ovarian protection of melatonin and its receptors against B(a)P exposure.

Polyethylene terephthalate (PET) materials were recycled by physical methods for a long time. Chemical degradation and recycling of PET materials draw more and more attention in recent years. In this work, PET materials were degraded and recycled via selective cleavage of ester bonds using ZnCl2 as catalysts in aqueous solution. Degradation system 70% ZnCl2/H2O presented excellent catalytic properties due to the coordination catalysis of Zn2+. Monomers terephthalic acid (TPA) was reclaimed at 180 °C for 8 h. The yield of TPA reached up to 98.31%, and the purity of TPA was up to 97.14%. The degradation system ZnCl2/H2O solution was recycled and reused for 3 times, and the degradation ratio of PET materials was still up to 100%. In the degradation process, no organic solvent was added. The work provides a green and sustainable strategy to recover high-value-added chemicals (TPA) from waste PET materials in aqueous phase.

Decidualization is a crucial precedent to embryo implantation, as its impairment is a major contributor to female infertility and pregnancy complications. Unraveling the molecular mechanisms involved in the impairment of decidualization has been a subject of interest in the field of reproductive medicine. Evidence from several experimental settings show that exposure to bisphenol A (BPA), an endocrine-disrupting chemical, affects the expression of several molecules that are involved in decidualization. Both low and high doses of BPA impair decidualization through the dysregulation of estrogen (ER) and progesterone (PR) receptors. Exposure to low doses of BPA leads to decreased levels and activities of several antioxidant enzymes, increased activity of endothelial nitric oxide synthase (eNOS), and increased production of nitric oxide (NO) via the upregulation of ER and PR. Consequently, oxidative stress is induced and decidualization becomes impaired. On the other hand, exposure to high doses of BPA downregulates ER and PR and impairs decidualization through two distinct pathways. One is through the upregulation of early growth response-1 (EGR1) via increased phosphorylation of extracellular signal-regulated protein kinases 1 and 2; and the other is through a reduced serum glucocorticoid-induced kinase-1 (SGK1)-mediated downregulation of epithelial sodium channel-α and the induction of oxidative stress. Thus, regardless of the dose, BPA can impair decidualization to trigger infertility and pregnancy complications. This warrants the need to adopt lifestyles that will decrease the tendency of getting exposed to BPA.

The tautomer structure of monosaccharides plays an important role in its conversion and utilization, which is mainly manifested in the selectivity of the product and the reaction mechanism. The tautomer distributions of N-acetyl- d -glucosamine (GlcNAc), a natural nitrogen-containing monosaccharide were investigated by quantitative 1H NMR (1H qNMR) and 13C NMR (13C qNMR) at 298 K under the condition commonly utilized for biorefinery. Catalysts used for biorefinery, i.e. BaCl2, KCl, ZnCl2, MgCl2, B(OH)3, SnCl4•5H2O and amino acid ionic liquid were introduced into D2O or DMSO-d6 to explore the tautomer distributions of GlcNAc. The introduction of ZnCl2 and SnCl4•5H2O promoted the conversion of α-pyranose to β-pyranose. The introduction of amino acid ionic liquid has little effect on the percentage of tautomers in D2O. However, when the amino acid ionic liquid, such as [Thr]Cl, was introduced into DMSO-d6, the proportion of β-pyranose increased to 29.06%, compared with no catalyst introduced. Besides, we also studied the tautomer distributions of GlcNAc in commonly utilized reaction solvents for biorefinery, such as N,N-dimethylformamide, N , N -dimethylacetamide, N-methyl-2-pyrrolidinone, ethylene and glycerol. In these solvents, the proportion of β-pyranose in N,N-dimethylformamide and glycerol was reduced to 25.84% and 38.38%, respectively. This study provides the basic experimental data of tautomer distributions of GlcNAc, and guided the conversion and utilization of GlcNAc in the future.

To achieve the goal of preparing an in situ microfibril composite (MFC), multiple strong shear flows were imposed on the melt of high-density polyethylene (HDPE)/polystyrene (PS). During vibration ...

The tautomer distributions of d ‑fructose, a popular model compound for biorefinery, in various lower alcohols and DMSO‑d6 (ROHs/DMSO‑d6) mixtures at 298 K were investigated by quantitative 13C NMR. The tautomer distributions of d ‑fructose in ethanol/DMSO‑d6 and methanol/DMSO‑d6 with different volume ratios of alcohols to DMSO‑d6 were also examined. For these normal alcohols (methanol, ethanol, n‑propanol and n‑butanol)/DMSO‑d6, the tautomer distribution of d ‑fructose in methanol/DMSO‑d6 exhibited the shortest equilibration time (46 h) and the lowest concentration of β‑furanose (39.0%) at equilibrium. The fraction of fructofuranose (α‑furanose and β‑furanose) at equilibrium and time needed to reach equilibrium in branched chain alcohols/DMSO‑d6 obey the following order: 2‑propanol/DMSO‑d6 (62.2%, 320 h) > tert‑butanol/DMSO‑d6 (61.6%, 307 h) > 2‑butanol/DMSO‑d6 (60.6%, 216 h) > isobutanol/DMSO‑d6 (57.8%, 134 h). For the diols/DMSO‑d6, the time for the tautomer distribution of d ‑fructose to reach the equilibrium was found to be: 1,4‑butanediol/DMSO‑d6 (113 h) > 1,2‑propanediol/DMSO‑d6 (38 h) > ethylene glycol/DMSO‑d6 (36 h). For ethanol/DMSO‑d6 and methanol/DMSO‑d6 with respectively different volume ratios, the experimental results showed that the high concentration of ethanol or methanol increases the conversion rate of tautomers.

Benzo(a)pyrene (BaP) is an endocrine-disrupting pollutant present in various aspects of daily life, and studies have demonstrated that BaP exerts reproductive toxicity. We previously showed that BaP damages endometrial morphology and decreases the number of implantation sites in early pregnant mice, but the mechanisms underlying these effects remain unclear. The endometrial function is crucial for implantation, which is associated with endometrial cell apoptosis. In this study, we focused on the effect of BaP on endometrial cell apoptosis and the role of WNT signaling during this process. Pregnant mice were gavaged with corn oil (control group) or 0.2 mg·kg-1 ·day -1 BaP (treatment group) from Days 1 to 6 of pregnancy. BaP impaired endometrial function by decreasing the expression of HOXA10 and BMP2, two markers of receptivity and decidualization. WNT5A and β-catenin were activated in the BaP group. BaP affected the expression of apoptosis-related proteins and inhibited the apoptosis of endometrial stromal cells. In vitro, human endometrial stromal cells (HESCs) were treated with different concentrations of BaP (dimethyl sulfoxide (DMSO); 5, 10 µM). WNT5A and β-catenin were also upregulated in the BaP treatment group. HESC apoptosis was restrained by BaP. Inhibiting WNT5A by SFRP5 partially restored the effect of BaP on apoptosis. In summary, these results suggested that BaP exposure during early pregnancy activates WNT5A/β-catenin signaling pathway, which inhibits the endometrial cell apoptosis and potentially destroys endometrial function.

The first principle calculations with on-site Coulomb repulsion U terms were carried out to investigate the 5-hydroxymethylfurfural (HMF) adsorption on the CuO(1 1 1) and Co3O4(1 1 0) surfaces, two widely used oxidation catalysts. The adsorption of HMF molecule is energetically favoured in both cases, and HMF is more inclined to bridge adsorption via hydroxyl and formyl groups binding with surface O and metal sites. Moreover, the adsorption energy relies on both the coordination type of surface lattice oxygen to which the H atom binds and the formation of H-bond involving hydroxyl and formyl groups on the adsorbed HMF. Also, the hydroxyl O H bond breaking is very easy and is likely to be the first step in HMF oxidation, and then the OH insertion reaction to produce 2,5-furandicarboxylic acid (FDCA). The corresponding experimental results also show that the CuO and Co3O4 surfaces are promising candidate catalysts.

Fischer–Tropsch wastewater (FTW), co-produced with hydrocarbons in Fischer–Tropsch process, is usually rich in water-soluble oxygenates, e.g. carboxylic acids, alcohols and aldehydes. Purification of FTW is crucial for achieving effective resource utilization and environmental concerns. The adsorption of FTW by humic acid (HA) has been studied via NMR. Butanol isomers, n-butanol (n-BuOH), sec-butanol (s-BuOH), iso-butanol (i-BuOH) and tert-butanol (t-BuOH), were used as model compounds of water soluble organic constituent for FTW. The interaction between HA and BuOHs was evaluated based on the NMR study. Lack of chemical shift change and broadening of peak width were observed with successive HA addition, 1H spin-lattice and spin-spin relaxation time of BuOHs decrease and 1H correction time increased. Association percentage to HA, association constants and Gibbs free energies for BuOHs were calculated. The adsorption efficiency of BuOHs decreased in the order: s-BuOH > n-BuOH > i-BuOH > t-BuOH. The effects of HA concentration and solution pH value on the interaction were examined, and the interaction is favored by increasing HA concentration, but less dependent on solution pH value. The studied process is effective for treating FTW and has a great potential for industrial applications due to its simplicity and low price.

Catalytic conversion of various carbohydrates into 5-hydroxymethylfurfural (HMF) and 5-ethoxymethylfurfural (EMF) was efficiently conducted by sulfonated carbon material (polyurethane based catalyst, abbreviated as PU-Cat). In the preparation process of catalyst, the tetrahydrofuran was reclaimed. PU-Cat exhibited excellent performance in the synthesis of HMF and EMF from fructose-based carbohydrates. Firstly, the dehydration of fructose into HMF was smoothly carried out in the low-boiling solvent (1, 4-dioxane), which was catalyzed by PU-Cat at 140 °C. The highest yield of HMF was up to 70.1% with full conversion of fructose in 1, 4-dioxane for 2 h. Then, the one-pot conversion of fructose into EMF was also successfully performed in the ethanol/1, 4-dioxane (V/V=70:30) at 140 °C for 2 h, and 66.0% yield of EMF was obtained. Finally, PU-Cat can be recycled five times without significant reduction in catalytic activity.

In the past few decades, some modified injection molding technologies aiming to fabricate highly oriented superstructure as “self-reinforcement” phase in injection molded samples, such as SCORIM, DPIM, and PVIM, have been extensively proven to be effective in improving mechanical properties of polyolefin. However, there is rare report focus on applying these technologies on reinforcing products with a more complex geometry structure until now. The vibration injection technology is currently researched at lab scale rather than wildly used in industry. Here we designed a lid-shaped part, of which the geometry structure is completely different from the rectangle or dumbbell used in the previous studies, and a novel multiflow vibration injection technology was hired to control the content of shish-kebab successfully. The self-reinforcement effect induced by shish-kebab was remarkable, indicated by the overall improvement in mechanical properties. This work gave a new insight into the practical application pro...

Deep eutectic solvents (DESs) exhibit similar physicochemical properties to the ionic liquids. They are inexpensive, renewable, nontoxic, and environmentally benign solvents and have gradually attracted attention in several fields, for example, biorefinery. Here choline chloride-based DESs have been used as solvents and catalysts for the preparation of deoxyfructosazine (DOF) through a self-condensation reaction of d-glucosamine (GlcNH2). The catalytic performances of a “green cocatalyst”, amino acids, and the reaction mechanism were also studied. The results displayed that choline chloride/urea was capable to convert GlcNH2 efficiently, with a 13.5% yield of DOF at low temperature and with a short reaction time (100 °C, 150 min). Among the screened amino acids, arginine showed the highest activity and gave the highest yield of DOF (30.1%) under the optimized reaction conditions. Nuclear magnetic resonance (NMR) studies revealed a strong hydrogen bond interaction between GlcNH2 and arginine. Moreover, a d...

An original route for levulinic acid (LA) conversion was achieved via C–C bond formation in a co-catalysis system containing Lewis and Bronsted acids. Different from conventional base-catalyzed processes, this acidic reaction system inhibits the carboxylic acid from deactivating the base catalyst, additionally simplifies the technical processes. The synergistic effect of the two types of acids effeciently catalyzed the dimerization reaction of LA to generate two C10 compounds, tetrahydro-2-methyl-5,γ-dioxo-2-furanpentanoic acid and 3-(2-methyl-5-oxo-tetrahydrofuran-2-yl)-4-oxopentanoic acid, with the total yield of 50.9% at 59.7% conversion. These products present high added value as fuel or fine chemical precursors.

As counter parts of ILs, DESs have received general interest because of their comparable physicochemical properties to ILs and facile preparation from readily available chemicals. In this work, the isomeric distributions of fructose, glucose, xylose and GlcNAc in CCU, CCG and CCO, i.e. basic, neutral and acidic DES, have been determined by 13C NMR. Higher furanose fraction of fructose was observed in CCO compared to CCG and CCU. The glucose was chosen as model compound to reveal the effect of DES on the mutarotation behavior with DMSO‑d6 as co-solvents. The experimental results showed that a high ratio of CCU to glucose speed up the mutarotation rate of glucose in DMSO‑d6, but have little influence on the anomeric distribution. Furthermore, the mutarotation of glucose in DESs is mainly driven by the HBD, whereas HBA provides little influence. However, HBD and HBA display a synergistic effect on the glucose mutarotation process. Hydrogen bonding between hydrogen of amino in urea and oxygen of hydroxyl in glucose is the driving force for the interconversion of anomers.

Hydrogenolysis is necessary for preparing various value-added chemicals from glycerol. Routine methods like GC and HPLC are not sufficient for analysis the reaction mixtures because the products usually have high boiling or similar polarity, especially when new chromatographic peaks are found which requires other technologies such as NMR. Although they were developed for years, but either DOSY or 1D selective TOCSY NMR has nature limitations. Herein we took their advantages and combined them to analyse glycerol hydrogenolysis mixtures for the first time. A model reaction mixture was first pseudo separated in DOSY spectrum, and 1D selective gradient TOCSY was further applied to assign the overlapped signal which could not be confirmed just by DOSY. A genuine reaction mixture was tried afterwards, and main signals could be assigned well in DOSY diffusion dimension. Notably, n-propanol was found as by-product by 1D selective gradient TOCSY, which is not visible in DOSY spectrum. The experimental results demonstrate that the combination of these two NMR methods could provide a fast, effective, feasible and reliable way for the identification of glycerol hydrogenolysis mixtures and is expected to apply in other research areas.

The degradation and recovery of waste polyurethane materials have confronted enormous challenge. Controllable degradation of polyurethane elastomer is developed via selective cleavage of C O of urethane linkages and C N bonds. It was founded that the selective cleavage of carbon-heteroatom bonds could be efficiently performed in 70% ZnCl2 aqueous solution. The transition metal Zn2+ coordinated with N and O atoms due to their unshared electron pairs. The C O of urethane linkages and C N bonds were readily cleaved using ZnCl2 as catalysts at 140 °C for 2 h. However, the C C bonds and C O C of ether linkages as framework structure remain intact in the degradation process. Eventually, the high-value-added chemicals including 2,4-diaminotoluene, polytetramethylene ether glycol (PTMEG) and 3,3′-dichloro-4,4′-diaminodiphenylmethane (MOCA) were retrieved via selective cleavage of C O of urethane bonds and C N bonds.

Diffusion-ordered spectroscopy (DOSY) is a powerful and efficient technique for the analysis of complex mixtures, relying on their differential in self-diffusion coefficient. However, DOSY is often struggled to separate signals pertaining to isomeric species, especially positional isomers. Here, for the first time, we describe the novel design of 18-crown ether-6 (18C6) and 18C6/K+ complex as matrixes to discriminate and identify positional isomeric mixtures of phenylenediamine, nitroaniline, phthalic acid, dimethoxybenzoic acid, aminophthalic acid and even amino acids using 1H DOSY spectrum. The superior performance of 18C6 and 18C6/K+ complex as matrix depends on that they can interact with different components with varying binding energy as demonstrated by MMMF calculations and the DFT calculation. The methodology presented here is simple yet efficient. Moreover, the crown ether and crown ether/K+ complex provide the dual mode discrimination for both amino and carboxylic substituted positional isomers.

In this study, rare earth (RE) metal doped ZrO2 was prepared by a surfactant-assisted coprecipitation/hydrothermal crystallization method and used to load Co as catalyst for the hydrogenation of aromatic carbonyl compounds in water. Furfural was hydrogenated to furfural alcohol in water with up to 95 mol % yield over Co/ZrLa0.2Ox at 40 °C, 2 MPa H2 in 10 h. The doping of rare earth metal oxide has three advantages: (I) it promotes the ZrO2 to reach a small-sized, stable, and high-activity tetragonal phase zirconia and thus lead to a high specific surface area for metal loading; (II) it interacts with Co to reach an ultrasmall average particle size of 1.1 nm; and (III) it modifies the ZrO2 surface to increase the amount of acidic sites for the adsorption of carbonyl feedstock. The adsorption experiment indicated a tight interaction between not only the carrier and C═O bond but also the Co clusters and C═O bond, which were of benefit for the hydrogenation of carbonyl groups. The surfactant addition during t...

The outer membrane (OM) of Gram-negative bacteria is a complex and asymmetric bilayer that antimicrobial peptides must disrupt in order to provoke the cell lysis. The inner and external leaflets of the OM are mainly composed of phospholipids (PL), and lipopolysaccharide (LPS), respectively. Supported lipid bilayers are interesting model systems to mimic the lipid asymmetric scaffold of the OM and determine the quantitative and mechanistic effect of antimicrobial agents, using complementary physicochemical techniques. We report the formation of asymmetric PL/LPS bilayers using the Langmuir-Blodgett/Langmuir-Schaefer technique on two different surfaces (sapphire and mica) with synthetic phospholipids constituting the inner leaflet and bacteria-extracted mutant LPS making up the outer one. The combination of neutron reflectometry and atomic force microscopy techniques allowed the examination of the asymmetric scaffold structure along the normal to the interface and its surface morphology in buffer conditions. Our results allow discrimination of two structurally related peptides, one neutral and inactive, and the other cationic and active. The active cationic plasticin PTCDA1-KF disrupts the asymmetric OM at relevant concentrations through a carpeting scenario characterized by a dramatic removal of lipid molecules from the surface.

This paper mainly explores the influence of different experiment factors on the angelica lactone self-aggregation process to synthesize C 10 , C 15 and C 20 self-aggregation products through Michael addition by base catalysis. Various experiment factors including types of catalysts, temperature, time and catalyst amounts are investigated in the angelica lactone self-aggregation process. And the possible mechanism of angelica lactone self-aggregation process catalyzed by carbonate is proposed. The results show that anhydrous potassium carbonate exhibits the higher efficiency and milder application conditions than other base catalysts. The different dominating products could be obtained by using anhydrous potassium carbonate under different experiment conditions. The optimal conditions for the angelica lactone dimer (C 10 ) are 10 wt% catalyst, 343 K and 30 min, and the maximal yield of dimer is 69.26%; the optimal conditions for the angelica lactone trimer (C 15 ) are 12 wt% catalyst, 333 K and 20 min, and the maximal yield of trimer is 49.89%; the optimal conditions for the angelica lactone tretramer (C 20 ) are 12 wt% catalyst, 343 K and 60 min and the maximal yield of tretramer is 62.46%.

Graphene oxide (GO) was used as an efficient and recyclable catalyst for the synthesis of N-substituted pyrrole using a Paal–Knorr condensation reaction between 2,5-hexanedione and aniline. The effects of reaction time, reaction temperature, solvent, catalyst loading and molar ratio of aniline to 2,5-hexanedione on the yield of 2,5-dimethyl-N-phenyl pyrrole were investigated. In situ NMR was used to follow the Paal–Knorr reaction at the molecular level. Results revealed that the oxygen-containing groups of GO, such as sulfonic acid and carboxyl groups, played a key role in this catalytic reaction. Polar protic solvents were favorable for the reaction. The catalytic activity increased with temperature without any side reaction. The GO could be easily recovered and showed remarkable reusability and excellent catalytic performance allowing it to be reused 5 times.

Selective conversion of glucosamine (GlcNH2) to deoxyfructosazine (DOF) and fructosazine (FZ) with additives was investigated. Significantly enhanced yield of DOF can be improved to 40.2% with B(OH)3 as the additive. Chemical shift titration (via one-dimensional nuclear magnetic resonance (1D 1H and 13C NMR)) and two-dimensional nuclear magnetic resonance (2D NMR) including 1H–13C HSQC and 1H–1H COSY are used to investigate intermolecular interactions between B(OH)3 and GlcNH2. Diffusion-ordered NMR spectroscopy (DOSY) was further employed to identify intermediate species. Mechanistic investigation by NMR combined with electron spray ionization–mass spectroscopy (ESI-MS) discloses that a mixed 1:1 boron complex was identified as the major species, shedding light on the promotional effects of B(OH)3, which is substantiated by density functional theory (DFT). Boron coordination effects make ring-opening and subsequent dehydration reaction thermodynamically and kinetically more favorable. Dehydration of dihy...