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A polyimide-based single-ion polymer PI-LiCPSI was prepared. PI-SIGPE obtained by compounding of PI-LiCPSI and PVDF-HFP showed good mechanical properties due to the rigid frame and strong interface, and also possessed excellent electrochemical and cycling performance.

Selective oxidation of methane to organic oxygenates over metal–organic frameworks (MOFs) catalysts at low temperature is a challenging topic in the field of C1 chemistry because of the inferior stability of MOFs. Modifying the surface of Cu-BTC via hydrophobic polydimethylsiloxane (PDMS) at 235 °C under vacuum not only can dramatically improve its catalytic cycle stability in a liquid phase but also generate coordinatively unsaturated Cu(I) sites, which significantly enhances the catalytic activity of Cu-BTC catalyst. The results of spectroscopy characterizations and theoretical calculation proved that the coordinatively unsaturated Cu(I) sites made H 2 O 2 dissociative into •OH, which formed Cu(II)-O active species by combining with coordinatively unsaturated Cu(I) sites for activating the C−H bond of methane. The high productivity of C1 oxygenates (CH 3 OH and CH 3 OOH) of 10.67 mmol g cat. −1 h −1 with super high selectivity of 99.6% to C1 oxygenates was achieved over Cu-BTC-P-235 catalyst, and the catalyst possessed excellent reusability.

The combination of ASA-0.4 and ASA-2 produces new acidic OH groups by increasing the contact points between silicon and aluminum. These OH groups improve the density of acid sites and increases the area of the active adsorption area of the support.

Li-rich PAF-6 synergized with CNs afforded efficient transfer channels for Li+, effectively preventing polysulfide dissolution and shuttle. The introduced –SO3H can also inhibit the shuttle effect. An excellent capacity retention rate of 85% after 100 cycles was achieved.

Background: Lung cancer is the most common malignant cancer worldwide. Targeted therapies have emerged as a promising treatment strategy for lung cancers. Objective: To evaluate the current landscape of targets and find promising targets for future new drug discovery for lung cancers, this research identified the science-technology-clinical development pattern and mapped the interaction network of targets. Methods: Targets for cancers were classified into 3 groups based on a paper published in Nature. We searched for scientific pieces of literature, patent documents and clinical trials of targets in Group 1 and Group 2 for lung cancers. Then, a target-target interaction network of Group 1 was constructed, and the science-technology-clinical (S-T-C) development patterns of targets in Group 1 were identified. Finally, based on the cluster distribution and the development pattern of targets in Group 1, interactions between the targets were employed to predict potential targets in Group 2 for drug development. Results: The target-target interaction (TTI) network of group 1 resulted in 3 clusters with different developmental stages. The potential targets in Group 2 are divided into 3 ranks. Level-1 is the first priority and level-3 is the last. Level-1 includes 16 targets, such as STAT3, CRKL, and PTPN11, that are mostly involved in signaling transduction pathways. Level-2 and level-3 contain 8 and 6 targets, respectively, related to various biological functions. Conclusion: This study will provide references for drug development in lung cancers, emphasizing that priorities should be given to targets in Level-1, whose mechanisms are worth further exploration.

The development of solid polymer electrolytes (SPEs) with high ionic conductivity, wide electrochemical window, and high mechanical strength is the key factor to realize high-energy-density solid lithium ion batteries (SLIBs). Porous aromatic frameworks (PAFs) have the advantages of high porosity, easily functionalized molecular structure, and rigid stable framework, which fully meet the requirements of solid polymer electrolytes with high Li

In this work, monodisperse positively charged polystyrene (PS) particles with a particle size of 900 nm were prepared by dispersion polymerization using methacryloxyethyltrimethyl ammonium chloride (DMC) as a cationic comonomer. The polystyrene/silica (PS/SiO2) composite microspheres with a raspberry structure are formed by electrostatic adsorption prepared using positively charged PS adsorbed negatively charged silicon dioxide (SiO2). A novel superhydrophobic coating was constructed by a dip-coating method. Then, the coating film was immersed in a solution of heptadecafluorodecyl trimethoxysilane in n-hexane (0.1 wt%) to carry out surface superhydrophobic modification. Finally, a superhydrophobic coating with 158° static contact angle and 3° sliding angle was obtained. In addition, by adding divinylbenzene (DVB) and changing the amount and size of SiO2, the effect of the roughness level and cross-linking structure of raspberry particles on the hydrophobic properties of the coating was studied. Mechanism diagram of superhydrophobic coating prepared by PS/SiO2 composite particles.

A kind of novel electromagnetic shielding sandwich coating material with excellent electromagnetic interference shielding and coating properties was explored in this work. The interlayer was obtain...

Monodisperse polystyrene microspheres with different functional groups have important applications in both the medical and analytical fields. In this study, we prepared monodisperse microspheres with sulfonic acid or carboxyl groups using soap-free emulsion polymerization (SFEP) with potassium persulfate as the initiator. A series of monodisperse polystyrene microspheres with sizes between 100 and 500 nm were successfully prepared by copolymerizing different types of ionic monomers at different concentrations. The microspheres were characterized by using dynamic light scattering (DLS), Zeta potential measurements (ZP), FT-IR spectroscopy, and transmission electron microscopy (TEM). The mechanism of the particle nucleation and growth were studied by combining the changes in particle size and the number of particles. The results showed that the addition of hydrophilic comonomers like sodium p-styrene sulfonate, acrylic acid, and methacrylic acid significantly improved the stability of the polystyrene microspheres and promoted particle nucleation, resulting in less particle aggregation and microspheres with smaller sizes.

Whole organ or tissue decellularized matrices are a promising scaffold for tissue engineering because they maintain the specific memory of the original organ or tissue. A whole organ or tissue decellularized matrix contains extracellular matrix (ECM) components, and exhibits ultrastructural and mechanical properties, which could significantly regulate the fate of stem cells. To better understand the memory function of whole organ decellularized matrices, we constructed a heart decellularized matrix and seeded cross-embryonic layer stem cells - neural stem cells (NSCs) to repopulate the matrix, engineering cardiac tissue, in which a large number of NSCs differentiated into the neural lineage, but besides that, NSCs showed an obvious tendency of trans-differentiating into cardiac lineage cells. The results demonstrated that the whole heart decellularized microenvironment possesses memory function. To reveal the underlying mechanism, TMT-based quantitative proteomics analysis was used to identify the differently expressed proteins in the whole heart decellularized matrix compared with a brain decellularized matrix. 937 of the proteins changed over 1.5 fold, with 573 of the proteins downregulated and 374 of the proteins upregulated, among which integrin ligands in the ECM serve as key signals in regulating NSC fate. The findings here provide a novel insight into the memory function of tissue-specific microenvironments and pave the way for the therapeutic application of personalized tissues.

A series of molybdenum-incorporated mesoporous silica (Mo–KIT-6) catalysts were successfully synthesized by a one-pot hydrothermal synthesis method, and were applied in the selective oxidation of methane to formaldehyde using oxygen as an oxidizing agent under atmospheric pressure. Comparatively, the corresponding supported catalysts (Mo/KIT-6) were prepared by incipient-wetness-impregnation method. The results of the small angle XRD, nitrogen adsorption/desorption isotherms, UV-vis, H2-TPR and UV-Raman spectroscopy characterization combined with the catalytic activity tests demonstrated that molybdenum atoms were inserted into the framework of the mesoporous materials for the Mo–KIT-6 catalysts and the highly dispersed MoO bonds dominantly existed, which were responsible for the efficient selective formation of formaldehyde. However, for Mo/KIT-6 catalysts, the molybdenum oxide species were mainly loaded on the surface or inside the outer pore channels of the support and abundant emergence of the Mo–O–Mo bond played a major role in the activation of methane to COx. Furthermore, with equivalent molybdenum content, the methane selective oxidation performance of 8Mo–KIT-6 was obviously better than that of 4.6Mo/KIT-6, and the formaldehyde yield (2.1%) of 8Mo–KIT-6 was 2.3 times as much as that (0.9%) of 4.6Mo/KIT-6. In situ and operando UV-Raman results demonstrated that the structures of the MoOx active sites have a strong effect on the formation and elimination of carbon deposition during the separated redox reaction with methane and O2, respectively. The polymerized MoOx active sites are favorable for the formation of graphitic carbon (G), which is called ordered carbon, while the isolated MoOx active sites are favorable for the formation of disordered carbon (D). The reduced highly dispersed MoOx active sites incorporated in the framework of silica are more easily reoxidized than those on the supported catalysts.

State of charge (SOC) and state of health (SOH) of batteries are the indispensable control decision variables for online energy management system (EMS) in modern internal combustion engine vehicles. The real-time and accurate determination of SOC and SOH is essential to the reliability and safety of EMS operation. Obtaining good accuracy for the SOC estimation is difficult without considering SOH because of their coupling relationship. Although several works on the joint estimation of SOC and SOH of lithium–ion batteries are available, these studies cannot be applied to lead–acid batteries because of the differences in physical structure and characteristics. This study handles the problem of modeling the relationship between SOC and SOH of lead–acid battery and their online collaborative estimation. First, the structure and control strategy of a bus-based EMS is discussed, and the improper energy control actions of EMS due to the inaccurate SOC estimation are analyzed. Second, an instantaneous correlation factor β for SOC and SOH is defined as a new state estimating variable, and the simplified linear relationship model between β and open circuit voltage is established through the battery experiments. Third, a discretized augmented system equation of β is deduced according to the relationship model and the Randles circuit model. The least square circuit parameter identification (LSCPI) algorithm is presented to identify the time-varying circuit model parameters, while the adaptive Kalman filter for augmented system (AKFAS) algorithm is employed to estimate β online. A collaborative estimation algorithm is proposed on the basis of the LSCPI and AKFAS to determine SOC and SOH of lead–acid battery in real time, and a demo intelligent battery sensor is developed for its implementation. The results of battery charging and discharging experiments indicate that the proposed method has high accuracy. The estimation accuracy of SOC of this method reaches 3.13%, which is 7% higher than that of the existing method.

In this paper, lignin (L)-based polyurethane (FeGLPU) with excellent electromagnetic shielding properties was prepared and studied. The modified reduced iron powder was modified with KH550, and then the obtained modified reduced iron powder (Fe) was mixed with lignin, polyethylene glycol 200 (PEG200), hexamethylene diisocyanate (HDI) and graphite (G) to in-situ synthesize the FeGLPU. The thermal stability, mechanical properties, electronic conductivity, and morphology of the composite FeGLPU were characterized in detail. The electromagnetic interference shielding effectiveness (EMI SE) of FeGLPU was tested in the frequency range of 8.2–26.5 GHz. When the content of Fe and G was fixed at 10% and the lignin content was 5%, the maximum EMI SE was 21.6 dB, and the frequency width of EMI SE greater than 10 dB was 18.3 GHz. The conductivity was 4.27×10−4 S/m, and the tensile strength of Fe10G10L5PU reached 11.7 MPa. When the lignin content increased to be 20%, the maximum EMI SE was 22.5 dB, and the frequency width of EMI SE greater than 10 dB was 18.3 GHz. The conductivity was 1.06×10−2 S/m, and the thermal decomposition temperature T5 (5% weight loss) reached 234 °C. The obtained excellent EMI SE should be due to the synergistic effect of Fe, G and lignin. It can be observed from the SEM observation that the G and Fe are uniformly dispersed in PU matrix with strong interfacial interaction. It was illustrated that the prepared FeGLPU was with efficient electromagnetic shielding properties, good mechanical properties, and high thermal stability. This lignin based electromagnetic shielding PU was proposed to have broad application prospects due to its low expenses and ecology friendliness.

A novel nanocomposite proton-exchange membrane (PEM) was obtained by combined electrospinning and solution casting of a composite solution of sulfophenylated poly(ether ether ketone ketone) (SP-PEEKK) and maleic anhydride modified nanocellulose (MN). SP-PEEKK was prepared by polymerization between phenyl hydroquinone and 1,4-bis(4-fluorobenzoyl)benzene followed by post-sulfonation. Nanocellulose (NCC) was prepared by the acid treatment of MCC with sulfuric acid, and MN with carboxyl group was obtained by modifying NCC with maleic anhydride. PEMs with 2% MN (MN2) showed a water uptake of 28% at 100°C, which was higher than that of MN0 (with 0% MN content). MN2 possessed a high tensile strength of 48.7 MPa, Young’s modulus of 1.3 GPa, and elongation at break of 34%, which was 54%, 21%, and 16% higher than those of MN0, respectively. Thus, the ordered distributed of MN was illustrated to be the effective reinforcing material for SP-PEEKK membranes because of the strong interface between the hydroxyl group of rigid MN and the sulfonic acid group of SP-PEEKK. MN2 also had a substantially higher proton conductivity of 0.09 S cm−1 at 90°C than MN0 (0.037 S cm−1). Therefore, combined electrospinning and solution casting was found to be a promising choice to improve the proton conductivity of nanocomposite PEMs, as promoted by the three-dimensional hydrogen bond-proton-transport network formed by the well-oriented MN in SPEEKK produced by the electrospinning.

Submicron polybutadiene particles were prepared using four different methods: one-step batch emulsion polymerization, pressure agglomeration, acid agglomeration, and polymer latex agglomeration. Core-shell elastomers were synthesized by grafting styrene and methyl methacrylate on polybutadiene particles. Transparent methacrylate-acrylonitrile-butadiene-styrene resin was prepared by blending the elastomers with methacrylate-styrene-acrylonitrile matrix resin synthesized by bulk polymerization. The effects of the construction method of submicron rubber particles on core-shell elastomer structure and composite properties were investigated. Additionally, the relationship between the rubber phase structure and composite properties was studied. The obtained results showed that the construction method significantly affected the size distribution and morphology of the submicron rubber particles. The rubber particles prepared by one-step batch emulsion polymerization were grafted easily, with 90.2% grafting efficiency of the corresponding core-shell elastomer. The grafting efficiency of the rubber particles prepared by acid agglomeration was only 69.4%. The former was most suitable as the toughening core of transparent Acrylonitrile-butadiene-styrene resin, and the transmittance and haze values of the composite were 90% and 2.4, respectively. Impact and tensile strengths were 185.6 J/m and 39 MPa, respectively. The acid agglomeration method generated submicron rubber particles more quickly, and the transmittance and haze of composite were 90% and 2.9, respectively. However, the impact and tensile strengths were reduced to 170.4 J/m and 31 MPa, respectively.

The research and development of abundant, non-toxic, low cost, and high-performance catalysts are urgently required for the production of propylene through propane dehydrogenation (PDH) reaction. H...

To solve the problems of chlorine loss and equipment corrosion caused by the conventional alumina-type catalytic reforming catalyst, a series of modified Zeolite Y catalysts supported with 0.3 w% Pt were obtained by the ion exchange of Mg2+, Ba2+ or Ce3+ and then by the impregnation of Pt(NH3)4(NO3)2 solution. Characterizations of the prepared zeolites and catalysts were performed using XRD, SEM, TEM, N2 adsorption-desorption, NH3-TPD, UV–vis DRS and Laser Raman. Catalytic aromatization performance of all the catalysts was investigated in a continuous-flow fixed-bed micro-reaction evaluation unit adopting industrial hydrofining naphtha as the feedstock with sulfur of 0.50 μg/mL. Results of the characterizations showed that Pt grains on the catalysts were distributed in nanometer state. It also showed that the framework of Zeolite Y was only damaged slightly and different acidic properties were generated after ion exchange. Results of the evaluation showed that ion exchange obviously increased aromatization activity of all the catalysts. The aromatization performance of Ce3+ modified catalyst Pt/CeY was the best, which had a reasonable selectivity and a higher activity than commercial alumina-type reforming catalyst.

Dairy cow mastitis is a common bacterial infectious disease which seriously threatens the development of the dairy cow industry. Previous studies have found that increased IFN-γ expression in dairy cows makes dairy cows more susceptible to mastitis, but the underlying mechanism is still not known. In this study, we utilized the in vitro bovine mammary epithelial cells (BMECs) model to explore the molecular mechanism via transcriptome sequencing technology, immunofluorescence, and Western blotting. It was found that IFN-γ promoted the adhesion and invasion of Staphylococcus aureus to BMECs through increasing the expression of TLR4-mediated CCL5 in BMECs. IFN-γ increased the activity of arginase II and reduced the level of arginine in cells, while the addition of arginine inhibited the expression of TLR4 and CCL5. An invasion experiment in mice further validated that IFN-γ treatment significantly increased the bacterial load in mammary glands and blood. However, the colonization and diffusion of S. aureus were interestingly decreased after Arg supplement. These data reveal that increased IFN-γ reduces arginine levels and activates TLR4-CCL5 signaling, leading to enhanced susceptibility of BMECs to S. aureus. Our findings are helpful to understand the pathogenesis of dairy cow mastitis and provide a theoretical basis for improvement of mastitis resistance in dairy cows.

Phosphoric acid-doped polybenzimidazole (PA-PBI) used in high-temperature proton exchange membranes (HT-PEMs) frequently suffers from a serious loss of mechanical strength because of the “plasticiz...

Several high-molecular-weight pillar[5]arene-containing poly(arylene ether sulfone) polymers were synthesized for the first time. Through grafting and crosslinking approaches, networks consisting of the molecular chains bearing multiple long-chain quaternary amine salts were fabricated. For the crosslinked membranes, high conductivity and low swelling were achieved even at low ion exchange capacity.

The surface-modified Al2O3 particles were introduced into polyethylene(PE) to enhance the thermal conductivity, and PE/Al2O3 cross-linked networks with improved thermal and mechanical properties were prepared through electron beam(EB) irradiation technology. The incorporation of reactive irradiation sensitizer was useful in fabricating a high degree of cross-linking(DC) PE networks under a low irradiation dose. In the PE sample containing 2% sensitizer, DC ca.67.1% could be obtained under 60 kGy(1 kGy=1000 J/kg). EB-irradiation greatly improved the tensile stress of PE-based samples, and the tensile stresses of the samples with 0.2%—5% TMPTA(trimethylolpropane triacrylate) under 60 kGy were 24.61—27.77 MPa. All the EB-irradiated samples had higher Vicat softening temperatures than the samples without irradiation. After treatment at 120 kGy, the Vicat softening temperatures of PE-Al2O3-44/ TMPTA-2 increased from 127 °C to 130.4 °C. SEM images revealed that PE-Al2O3-50 samples with increased amount of Al2O3 particles showed a conduction “pathway,” and thermal conductivity reached 0.67 W/(m·K). Thus, high-performance pipes were successfully extruded, which could satisfy the static hydraulic blasting test and exhibit improved thermal conduction capability.

As is well known, changing continuous phase properties has a great influence on the nucleation mechanism and particle size, and the addition of electrolytes or alcohol is the main mean to c...

Study on proton exchange membrane (PEM) with the aim toward excellent battery performance of PEM for fuel cells has attracted increasing attention. In this work, nanocellulose (CNC) aminated by KH792 noted as NN was prepared. CNC or NN/sulfophenylated poly(ether ether ketone ketone) (sPEEKK) nanocomposite membrane (SN) or (SNN) were produced by solution mixing. SNN was further coated with tetraethyl orthosilicate (TEOS) to obtain SNNT. The properties of sPEEKK, SN, SNN, and SNNT membranes were thoroughly investigated. The proton conductivity of SN4 was 0.22 S·cm⁻¹ at 90 °C, while a proton conductivity of 0.30 S·cm⁻¹ was obtained for SNN4, and an even higher value of 0.36 S·cm⁻¹ at 90 °C was obtained for the TEOS‐coated SNN4 (SNN4T). Meanwhile, SNN4T showed high thermal stability, and its Td₅ was as high as 318.2 °C. Furthermore, the composite membrane coated with TEOS also presented excellent oxidative stability. The mass of SNN2T after treated in Fenton agent for 1 h at 80 °C was still retained 96.2%, and it was not fully dissolved until 11 h. It was illustrated that aminated CNC/sPEEKK nanocomposite membranes coated with TEOS is a kind of promising materials as PEMs for fuel cells. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2190–2200

In this study, a novel approach for preparing 50 wt% solid content cationic poly(methyl methacrylate) (PMMA) latexes with narrow particle size distribution (PSD) using macroemulsion polymerization ...