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Process analysis of heterogeneous catalytic reactions such as lignin depolymerization is essential to understand the reaction mechanism at the molecular level, but it is always challenging due to harsh conditions. Herein, we report an operando process analysis strategy by combining a microbatch reactor with high-resolution mass spectrometry (MS) via a reactor-integrated electrospray ionization (R-ESI) technique. R-ESI-MS expands the applications of traditional in situ MS to a heterogeneous and high-pressure liquid-phase system. With this strategy, we present the evolution of a series of monomers, dimers, and oligomers during lignin depolymerization under operando conditions (methanol solvent, 260 °C, ∼8 MPa), which is the first experimental elucidation of a progressive depolymerization pathway and evidence of repolymerization of active monomers. The proposed R-ESI-MS is crucial in probing depolymerization intermediates of lignin; it also provides a flexible strategy for process analysis of heterogeneous catalytic reactions under operando conditions.

Superconcentrated "water-in-salt" electrolytes have greatly widened the electrochemical stable window (ESW) of aqueous electrolytes, but they also generate new problems, including high costs, high viscosity, and low conductivity. Here we report a 2 m low concentration electrolyte using an N,N-dimethylformamide/water (DMF/H2O) hybrid solvent, which provides a wider ESW (2.89 V) than an aqueous electrolyte (2.66 V) and presents nonflammability, high conductivity, and low viscosity characteristics. In 2 m DMF/H2O hybrid electrolyte, the LUMO energy of the DMF solvent (-0.00931 a.u.) is lower than that of H2O (-0.00735 a.u.), which could effectively promote the degradation of FSI- and lead to stable solid electrolyte interphase formation. As a result, the electrochemical reversibility and cyclability of the KTi2(PO4)3@C (KTP@C) anode in the aqueous electrolyte have been significantly enhanced with the help of DMF addition. Moreover, the K2Zn3(Fe(CN)6)2 (KZnHCF)//KTP@C full potassium-ion battery exhibits highly efficient stability and rate capability with a long cycle performance over 10 000 cycles and delivers a specific discharge capacity of 33 mAh g-1 at a high current density of 20 A g-1. Low concentrations of DMF/H2O hybrid electrolytes can inhibit the hydrogen evolution reaction of aqueous electrolytes, providing more opportunities for the practical application of electrode materials. Not limited to DMF solvent, mixing organic and aqueous solvents will provide more available options and perspectives for improving the energy density and long cycle performance of the aqueous metal-ion battery.

Context Although the role of n-6 polyunsaturated fatty acids (PUFAs) in age-related macular degeneration (AMD) has been studied in previous observational studies, the precise manner in which 1 or more n-6 PUFAs account for this relationship remains unclear. Objective Using genetic instruments for n-6 PUFAs traits implemented through mendelian randomization (MR), we aimed to study possible causal associations between n-6 PUFAs and AMD. Methods The 2-sample MR method was used to obtain unconfounded causal estimates. We selected genetic variants strongly associated (P Results Our MR analysis suggested that circulating LA was a causal protective factor for AMD, with an odds ratio (OR) estimate of 0.967 (95% CI 0.945 to 0.990; P = .005) per percentage in total fatty acid increase in LA. In contrast, higher genetically predicted circulating AA causally increased the AMD risk (OR = 1.034; 95% CI 1.012 to 1.056; P = .002). Sensitivity analysis provided no indication of unknown pleiotropy. The findings from different single-nucleotide polymorphism selections and analytic methods were consistent, suggesting the robustness of the causal associations. Conclusion Our study provided genetic evidence that circulating LA accounted for protective effects of n-6 PUFAs against the risk of AMD, whereas AA was responsible for deleterious effects on higher AMD risk.

As the laws about emission of volatile organic compounds (VOCs) become more and more stringent, low VOC content coatings, such as high solid polyurethane coating, gradually attract great attention. Herein, a series of star-shaped hydroxyl polyesters (SHPs) were synthesized by methyl hexahydrophthalic anhydride (MHHPA), diisopropanolamine (DIPA), and monoglycidyl ether. The number of their average molecular weights is ranged from 913 to 1390 with 1.55–1.75 of PDI. The viscosities of SHPs are low to 1060 mPa·s. The molecular structures of SHPs were characterized by Fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (1H NMR) spectroscopies. The high-solid two-component polyurethane coatings (2 K-PU) from SHP-3 have a 65% of the solid contents and exhibit 20 mPa·s of the applied viscosity with 310 g/L of VOC contents. Moreover, the polyurethane film displays high coating hardness up to 2H, as well as excellent chemical resistance and good thermal stability.

SrAl2O4: Eu2+, Dy3+ (SAOED) and Y2O2S: Eu3+, Mg2+, Ti4+ (YOS), as two kinds of important rare earth luminescent materials, are widely used in fibers due to their excellent luminescent properties. However, the lack of sensing property limits the application areas of the fibers in intelligent materials. In this work, the thermochromic luminescent fiber (TLF) was prepared by wet spinning from the cellulose acetate (CA)/dimethyl formamide (DMF) spinning solution. The rare earth luminescent materials serviced as the luminescent sources and thermochromic pigments (TP) acted as the thermochromic agent in this color changing system. The absorptivity curves and fluorescence spectra were recorded at 25 and 45 °C to investigate the thermosensitive characteristics of the fiber. The scanning electron microscope (SEM) observation presents that the TLFs were cylindrical with the diameters of 300–400 µm and three kinds of particles were evenly distributed in the cellulose matrix. X-ray diffraction (XRD) results confirm that cellulose matrix and the wet spinning process did not destroy the phase of rare earth luminescent materials in the fiber. Thermal stability of TLF was illustrated by differential scanning calorimetry (DSC) and thermal gravity analysis (TGA). Absorptivity and emission spectra measurement indicates that the TLF had perspicuous thermochromic luminescence properties. Decay curves showed that the TLF glowed continuously. This work exploits a new type of intelligent luminescent fiber that can respond to ambient temperature, which broadens its application in sensors.

Development of multifunctional materials and devices has garnered enormous attention in the field of organic optoelectronics; nevertheless, achieving high mobility together with strong luminescence in a single semiconductor remains a major bottleneck. Here, a new multifunctional semiconductor molecule, 2,7-diphenylbenzo[4,5]thieno[3,2-b]benzofuran (BTBF-DPh), that integrates high charge transporting [1]benzothieno[3,2-b][1]benzothiophene with a strongly emissive furan group, is synthesized and applied in three types of optoelectronic devices, including organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), and organic phototransistors (OPTs). OLEDs based on BTBF-DPh as the emissive layer showed a blue emission with CIE coordinates of (0.151, 0.069) and a maximum current efficiency of 2.96 cd A-1 with an external quantum efficiency of 4.23%. Meanwhile, OFETs fabricated with BTBF-DPh thin film manifested a carrier mobility of 0.181 cm2 V-1 s-1, which is comparable to that of thiophene-based counterparts. Additionally, BTBF-DPh-based OPTs exhibited a maximum responsivity and detectivity of 2.07 × 103 A W-1 and of 5.6 × 1015 Jones, respectively. On the one hand, our rationally designed material, BTBF-DPh, has a dense and close-packed structure with an extended π-conjugation, facilitating charge transport through adjacent molecules. On the other hand, the weakened dipole-dipole interactions between BTBF-DPh molecules that resulted from the unambiguous J-aggregation and reduced spin-orbit coupling caused by replacing sulfur atom significantly suppress the exciton quenching, contributing to the improved photoluminescence performance. These results validate that our newly developed BTBF-DPh is a promising multifunctional organic semiconductor for optoelectronic devices.

Composite red luminescent material SMED/LCA (Sr2MgSi2O7:Eu2+,Dy3+/light conversion agent) is a phosphor with long afterglow, which was prepared by LCA and SMED at a certain mass ratio. It has excellent characteristics, such as high lightness and emitting red light, but poor stability properties because LCA falls off easily from the surface of SMED. Here, SiO2 (Al2O3 or MgF2) was coated on the surface of SMED/LCA through the heterogeneous deposition method to prepare a stable composite phosphor, adding coated phosphor into a polyacrylonitrile (PAN) fiber-forming polymer and wet spinning to form SMED/LCA-PAN (composite red light-emitting fiber). The surface element distribution, phase structure and luminescence properties of SMED/LCA-PAN were characterized. The results show that SiO2 (Al2O3 or MgF2) is successfully coated on the surface of the material, and the coating has no effect on the phase of SMED in the fibers. The intensity red/blue ratio (Int.600 nm versus Int.470 nm) of coated SMED/LCA fiber in the afterglow emission spectrum increases by about 1.9 times; the increase in energy conversion efficiency indicates the enhancement of the red light effect. In addition, the afterglow initial brightness is up to 0.148 cd/m2 after 15 min of ultraviolet light excitation, and the luminous fiber still has high afterglow brightness.

Measuring or monitoring air humidity is an increasing demands in the various fields. In this work, a simple and convenient method was utilized to prepare a melamine aerogel (MA) based sensor for humidity measurement. The sensing material was made from polymerization of polypyrrole (PPy) in the matrix of MA. The surface morphology was characterized by scanning electron microscopy (SEM) to examine the inner structure of the sensing material. MA was chosen as the substrate owing to the porous structure, which facilities the adsorption of water molecules from the air. The self-powered humidity sensor was manufactured by adhering conductive tapes on both side of PPy modified MA (PPy@MA). The sensor has a flexible, ultralight and ultraporous structure, and could generate humidity-induced open-circuit voltage from the concentration gradient of the H+ ions. The PPy@MA sensor exhibited the response and recovery time of 1.1 s and 4.5 s, respectively, when it is used for sensing the flowing wet air (RH 75 %). Furthermore, the sensitivity of the self-powered humidity sensor was evaluated by assessing the moisture changes of the human skin, and the moisture from the human breath.

In order to improve the red luminous properties of luminescent fibers, Sr2MgSi2O7:Eu2+, Dy3+ and light conversion agents were treated with silane (KH560), aluminate (DL-411-A), and aluminum zirconium coupling agents (LD-139-3) to prepare composite luminescent materials. And then they were added to a polyacrylonitrile (PAN) fiber-forming polymer and through wet spun to form composite red light-emitting fibers. The surface morphology, phase structure, and luminescence properties of the composite red light-emitting fibers were characterized by scanning electron microscopy, X-ray diffraction, fluorescence spectrometry, and afterglow brightness tester. Results showed that all of the three kinds of coupling agents influenced the red light of the luminescent fibers. The aluminate ester coupling agent had more effect than that of the other two coupling agents. After treatment with the aluminate coupling agent, the surface of the luminescent material became rough and adhered to the particles of light conversion agent. The intensity of the emission peak of the luminescent fibers at 470 nm decreased, and the emission peak intensity at 595 nm improved. The initial afterglow brightness and afterglow duration remained unchanged after 15 min of ultraviolet light excitation, as well as the color purity increased by approximately 1.6 times.

Herein, we report a new molecule structure modification strategy for non-fullerene small-molecule electron acceptors (NFAs) for solar cells through trifluoromethylation of end-capping groups. The synthesized trifluoromethylated acceptor ITCF3 exhibits narrower band gap, stronger light absorption, lower molecular energy levels, and better electron transport property compared to the reference NFA without the trifluoromethyl group (ITIC). Bulk heterojunction solar cells based on ITCF3 combined with the PM6 polymer donor exhibit a significantly improved power conversion efficiency of 13.3% compared with the ITIC-based device (8.4%). This work reveals great potential of trifluoromethylation in the design of efficient photovoltaic acceptor materials.

The fluorination of polymer donors through substituting hydrogen atoms by fluorine atoms on aromatic rings have been widely used in highly efficient polymer solar cells (PSCs). However, this fluorination process suffers from complicated synthesis and low yields. Herein, through replacing the methyl group with a trifluoromethyl group, the feasibility of synthetically-simple fluorination towards high-performance polymer donors is demonstrated. Two structurally similar polymer donors, one having a trifluoromethyl (–CF3) group and the other with a methyl (–CH3) pendant group for comparison, were designed and synthesized. By comparing these two donors, we found that the –CF3 group addition lowered the HOMO energy level and increased absorption through improved intermolecular interactions. Single-junction solar cells based on the trifluoromethylated donor yield a maximum power conversion efficiency of 13.5%, representing a nearly two-fold increase compared with that of devices using the methylated counterpart. These findings reveal great potential of fluorinating polymer donors by the trifluoromethyl group to improve solar cell performance.

Polyacrylonitrile/silver@polyaniline (PAN/Ag@PANI) composite nanofibers were prepared via electrospinning and photo-assisted technique. PAN nanofibers fabricated using electrospinning acted as templates, and then Ag@PANI compound were synthesized by in-situ polymerization method assisted with photo and grew onto the surface of PAN nanofibers. The obtained PAN/Ag@PANI composite nanofibers were tested as ammonia sensors at room temperature towards low detection range (400 ppb-200 ppm), and their response values were compared to that of PAN/PANI composite nanofibers produced with the same technique. The results show that the PAN/Ag@PANI composite nanofibers presented higher response values, ideal recovery time, repeatability and selectivity. But with the increase of Ag in the composite nanofibers, the response values did not improve, because Ag acted as a dopant when its content was not very high, and if there was too much Ag existed in the sensors, the electrical conductivity depended more on the silver.

In this work, titanium dioxide (TiO2) was modified with reduced graphene oxide (rGO), and then coated on filter paper to prepare the rGT/FP photoelectrode for the photoelectrocatalytic (PEC) decolorization of methylene blue (MB). The physicochemical properties of the rGT/FP photoelectrode were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and UV-Vis diffuse reflectance spectroscopy (DRS). The decolorization results demonstrated that the photocatalytic (PC) and electrocatalytic (EC) efficiency of the photoelectrode could be significantly improved by the modification of rGO. The improvement of PC and EC efficiency might attribute to the existence of rGO, which could extend the light-harvesting efficiency, promote the photocurrent response value and suppress the charge recombination. Furthermore, the PEC decolorization of MB using the rGT/FP photoelectrode presented higher efficiency than the sum of PC and EC decolorization, indicating the synergistic effect between the photo and electrical energy.

Herein, we propose a new strategy to develop air-stable n-type organic semiconductors with non-classical thiophene aromatic diimide derivatives by replacing aromatic naphthalene with a heteroaromatic isothianaphthene core. We designed and successfully synthesized the isothianaphthene core based diimide material, N,N ′-bis( n -hexyl)isothianaphthene-2,3,6,7-tetracarboxylic acid diimide ( BTDI-C6 ) as an n-type semiconductor. Compared to N,N ′-bis( n -hexyl)naphthalene-1,4,5,8-tetracarboxylic acid diimide ( NDI-C6 ), BTDI-C6 possesses a deeper LUMO energy level of −4.21 eV, which is 0.32 eV lower than that of NDI-C6 . Both molecular modelling and experimental results elucidated that organic thin film transistors (OTFTs) based on both of these materials exhibit comparable mobilities; however, the threshold voltage of BTDI-C6 based device (+7.5 V) is significantly lower than that of NDI-C6 based counterpart (+34 V). Moreover, the low-lying LUMO energy level of BTDI-C6 ensures excellent air-stability which is further validated by the device performance. In addition, BTDI-C6 shows high luminescence while NDI-C6 is not luminescent at all in solution, which reveals the potential application of our newly synthesized material in n-type light-emitting transistors.

The in-depth study of the cleavage behaviors of linkages in biomass is important for the better understanding of biomass pyrolysis mechanism. This study aimed to clarify the pyrolysis mechanism of the typical ether linkages in biomass including β-1,4-glycosidic bond, α-O-4 bond and methoxyl using cellobiose, benzylphenyl ether and guaiacol as the model compounds. Combining the detection of the key intermediates, especially radicals by SVUV-PIMS and the evaluation of the reaction pathways by density functional theory (DFT) quantum chemical calculations, it was found that the concerted cleavage of β-1,4-glycosidic bond was more kinetically favorable than homolytic cleavage and heterolytic cleavage, and the ring opening of cellobiose via the breakage of C1′-O was likely to occur before the cleavage of glycosidic bond. The α-O-4 bond in benzylphenyl ether was mainly cleaved by Cα-O homolysis, and it was easy for the formed radicals to recombine with each other to yield phenolic dimers. In the initial evolution process of methoxyl in guaiacol, homolytic demethylation was the most important unimolecular reaction, while demethoxylation and radical-induced rearrangement reactions were difficult to occur due to their high energy barriers. In the presence of the formed methyl radicals from homolytic demethylation reaction, these two reactions would occur since their energy barriers were significantly reduced at this condition.

A gas-phase reaction network involving reactive intermediates such as alkyl and alkyl peroxide radicals and alkyl hydroperoxides have long remained a mystery in oxidative coupling of methane (OCM) and oxidative dehydrogenation of ethane (ODHE) reactions. Herein we report direct observations of gas-phase reactive intermediates including CH2, CH3•, C2H5•, CH3OO•, C2H5OO•, CH3OOH, and C2H5OOH during OCM and ODHE reactions over Li/MgO catalysts with an online synchrotron VUV photoionization mass spectrometer connected to a catalytic reactor with adjustable distances between the catalyst bed and the sampling nozzle of the mass spectrometer. Secondary reactions of these reactive intermediates in the gas phase are elucidated, and the reaction network of OCM and ODHE reactions is established. These results greatly deepen the mechanistic understanding of OCM and ODHE reactions necessary for developing efficient catalysts and designing proper reactors.

In this work, a series of fluorescent cathodically coloring electrochromic (EC) small molecules o-, m-, and p-DBFDCz with 3,5-di(9H-carbazol-9-yl)benzene (DCz) linked to dibenzofuran (DBF) at diffe...

The aromatic substituents such as phenyl and thienyl have a direct impact on the structure-property relationship of conjugated semiconducting molecules and thus play a significant role in determining the performance of organic thin film transistors (OTFTs). To design a molecule with good charge transport properties, it is essential to understand the charge transfer process. Herein, through the study of two groups of classical OTFT materials with different substituents, we demonstrate the fundamental reasons for the contrasting carrier mobilities between the materials in each group by means of DFT calculations. The results from our theoretical analysis on the two groups of molecules provide very good estimates of their charge transfer properties and the numerical trend from our calculation is consistent with that from the corresponding experimental results. We reveal in detail the impacts of the subtle geometric differences caused by different substituents from two aspects including (i) the significant influence of steric hindrance on reorganization energy and (ii) the overlap of the adjacent molecular orbitals (MOs) on electron coupling. Overall, our systematic investigation into the charge transfer mechanism and geometry effects allows us to employ a reliable theoretical methodology for the prediction of the material performance, which is crucial for the design of high performance OTFT materials.

The gate dielectric layer is one of the important components in organic thin film transistors (OTFTs) which affects the charge mobility, power consumption and stability of the device. Here, we report new composite polymer dielectrics prepared by sol–gel chemistry from commercial siloxanes and poly(vinyl alcohol), featuring a high dielectric constant (k ∼ 8–16) and hydrophobicity. OTFTs fabricated with the developed polymer dielectric exhibit ultra-low driving voltage (

Herein, we designed and synthesized a highly fluorescent non-fullerene acceptor (ANT-4F) based on an anthracene (ANT) core. OSCs based on ANT-4F/PBDB-TF exhibited a significantly decreased Vloss,non-rad of 0.22 V (calculated from high EQEEL = 1.7 × 10−4). Simultaneously, high charge-transfer state energy (ECT = 1.54 eV) was obtained. Compared with OSCs based on IT-4F/PBDB-TF, a reduced Vloss,non-rad and higher ECT concurrently contributed to an increased Voc of 0.93 V. Consequently, despite the lower Jsc of 19.0 mA cm−2, an overall high PCE of 13.1% can be obtained. This work exemplified the great potential for highly fluorescent NFSAs in decreasing Vloss,non-rad and improving PCEs.

Anthracene derivatives constitute the active elements in high performance organic semiconductors and in order to find ubiquitous electronics applications, the investigation of new materials with high stability and mobilities is critical. Despite the versatility of substituent groups in anthracene and the extensive research works on anthracene derivatives, the exploration and discovery of high-performance anthracene derivatives can be impeded by the difficulty in molecular designing and synthesis techniques. Theoretical modeling is a powerful instrument and a variety of modeling methods with different accuracy levels have been reported. However, there is no systematic research work on theoretical prediction of the fundamental properties of anthracene derivatives so far. Here, density functional theory calculations are performed on anthracene derivatives to systematically address the prediction accuracy in energy levels as compared to our experimental data and it is shown that the PBE0/6-311G(d,p) is a more cost-effective method. Based on the influence of diverse substituent groups on energy levels, we present a strategy to design high-performance anthracene derivatives with specific energy levels, which are predicted to be excellent candidates for charge transfer materials. Therefore, the strategy may offer a guide for tailoring materials' functional properties via modifications of the molecular units before materials synthesis and open up new possibilities for the discovery of rising organic semiconductors.

To investigate the effects of tertiary amination/hydroxypropylsulfonation on the adhesion-to-fibers and film properties of corn starch for warp sizing, a series of tertiary aminated and hydroxypropylsulfonated corn starch (TAHPSS) samples were prepared by the tertiary amination and hydroxypropylsulfonation of acid-hydrolyzed corn starch (AHS) with 2- dimethylaminoethyl chloride hydrochloride (DMC-HCl) and 3-chloro-2-hydroxy-1-propanesulfonic acid sodium salt (CHPS-Na) simultaneously. The adhesion was evaluated by measuring the bonding force of starch to the fibers. The film properties were investigated in terms of tensile strength, breaking elongation, degree of crystallinity, and moisture regain. The results showed that tertiary amination/hydroxypropylsulfonation was able to increase bonding forces of starch to cotton and polyester fibers, enhance breaking elongation and moisture regain of the starch film and to decrease the tensile strength and degree of crystallinity of the film, thereby improving the adhesion and reducing film brittleness. Increasing the level of tertiary amination/hydroxypropylsulfonation was favorable for gradually improving the adhesion and decreasing the brittleness. The TAHPSS showed potential for use in cotton warp sizing.

2-(4-(octyloxy)phenyl)[1]benzothieno[3,2-b][1]benzothiophene (C8-OPh-BTBT), a liquid crystal material, is designed and successfully synthesized by introducing an alkoxy side chain of BTBT core. The organic thin-film transistors (OTFTs) based on C8-OPh-BTBT are fabricated to investigate the charge transport properties and compare with that of the alkyl side chain substituted semiconductor such as C12-Ph-BTBT. The highest mobility of 8.25 cm2 V−1 s−1 in C8-OPh-BTBT-based OTFTs is obtained when fabricated at a highly ordered Smectic X (X = K or H, SmX) liquid crystal phase, which is attributed to the formation of a bilayer structure of the organic semiconductor. Notably, the mobility of alkyoxy-substituted C8-OPh-BTBT-based OTFTs is much higher than that of alkyl-substituted C12-Ph-BTBT based OTFTs, while decreasing the operating threshold voltage. This study reveals that the introduction of alkoxy side chain of BTBT core is an effective way to alleviate the high threshold voltage and improve the charge mobility, which indicates that C8-OPh-BTBT-based OTFTs have the potential in practical applications.

The polyacrylonitrile composite fibers with white persistent luminescence were prepared by adding different concentrations of Sr2ZnSi2O7: Eu2+, Dy3+ (SZO) and Rhodamine B fluorescent pigments (FP) into polyacrylonitrile spinning solution. Morphology, phase structure, color properties, photoluminescence properties and afterglow properties were examined. Photoluminescence test indicated that the emission spectrum of Sr2ZnSi2O7: Eu2+, Dy3+ phosphors overlapped with the excitation spectrum of fluorescent pigments in the range of 450–550 nm, which was the necessary condition for the energy transfer from the Sr2ZnSi2O7: Eu2+, Dy3+ to the Rhodamine B fluorescent pigments (FP). The phosphorescent color of the composite fibers showed that the white luminescent polyacrylonitrile fibers can be gained when weight ratios of SZO/FP ranged from 10:0.2 to 10:0.5. Decay curves suggested that the as weight ratio of SZO/FP was less than 10:0.75, the initial brightness of the composite fibers could not be significantly reduced.

We report the synthesis and characterization of a non-liquid crystalline material, 2-phenylchrysene (Ph-CHR), and a liquid crystalline material, 2-(4-dodecyl phenyl)chrysene (C12-Ph-CHR), and discuss their organic thin-film transistor (OTFT) device performances. The concept of designing chrysene derivatives is derived from the similar electronic structure of chrysene and [1]benzothieno[3,2-b][1]benzothiophene (BTBT), which is a very famous core for organic semiconductors. OTFTs, based on Ph-CHR and C12-Ph-CHR, are fabricated by vacuum-deposition on octyltrichlorosilane (OTS(8)) treated Si/SiO2 substrates. Our experimental results show that OTFTs based on Ph-CHR possess higher mobility than OTFTs based on BTBT derivative 2-phenyl[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT). The liquid crystalline material C12-Ph-CHR achieves the highest carrier mobility of up to 3.07 cm2 V−1 s−1 with an on/off ratio of 3.3 × 106 for polycrystalline organic thin-film transistors in ambient air. The results indicate that the chrysene derivative C12-Ph-CHR is a promising candidate for applications in electronic devices.

Selective hydrogenation of nitroarenes is an important chemical transformation to obtain functionalized anilines as key intermediates for pharmaceuticals and fine chemicals. Compared to the well-studied noble metal catalysts, heterogeneous catalysts based on low-cost transition metals are rarely reported. In this study, we developed an efficient and controllable route to synthesize a new kind of heterogeneous catalyst of iron phosphide nanoparticles encapsulated in a doped carbon matrix for the chemoselective hydrogenation of aromatic nitroarenes to anilines. Making use of the chemical reaction between Fe atoms in a MIL-88B-NH2 core and phosphorus atoms in a poly(cyclotriphosphazene-co-4,4′-sulfonyldiphenol) (PZS) shell, iron phosphide nanoparticles encapsulated in a doped carbon matrix were successfully prepared through direct calcinations of a Fe-MOF@PZS core@shell precursor at 900 °C for 2 h under an Ar atmosphere. Due to the relative high surface area and porous structure as well as small nanoparticles, the prepared catalyst showed high catalytic activity, excellent selectivity and recyclability for the hydrogenation of aromatic nitroarenes to anilines.

Hollow carbon nanospheres have received much interest by virtue of the special shape, low density and large interior void space, allowing their many potential applications. Here we report a template-free route to produce nitrogen-doped hollow porous carbon spheres (denoted as N-HPCSs) through amination reaction of C 60 with alkyl diamines and subsequent carbonization. The size of wall thickness and cavity of hollow carbon spheres could be easily regulated by the chain length of alkyl diamines. After carbonization in Ar atmosphere, the obtained N-HPCSs exhibited excellent activity and recyclability for hydrogenation of aromatic nitro compounds with hydrazine hydrate. The facile approach presented in this work provides a new way for preparation of doped hollow porous carbon spheres.

The aim of this work is to investigate the luminescence color changes of thermosensitive luminous fibers (TLFs). These TLFs are comprised of rare-earth luminescent materials as the luminescence sources, reversible thermochromic crystal violet lactone (CVL) pigment as the luminescence conversion agent, and polyacrylonitrile (PAN) as the matrix. It was found that the TFLs could not only change their color, but also convert the luminescence upon temperature change based on a structural transformation of the CVL pigment. X-ray diffraction (XRD) measurements indicated that rare-earth luminescent materials maintained their basic crystal structure and the CVL pigment was not destroyed by the process of spinning. The scanning electron microscopy (SEM) images of TLFs at the microcosmic angle showed that the CVL pigments were evenly distributed in the PAN matrix and formed a luminescence filter on the surface of the fiber. The differential scanning calorimetry (DSC) and thermogravimetry (TGA and DTG) results indicate that the TLFs possess satisfactory thermostability below 212.6 °C. The color and luminescence of the TLFs were accurately exhibited on the CIE 1931 chromaticity coordinates. The thermosensitive capability of TLFs was qualitatively verified by observing them in water at 40 °C and it was found that the fibers had brilliant luminescence and vivid thermosensitivity.

In this study, thermosensitive luminous fibers (TLFs) were prepared by wet spinning, using polyacrylonitrile as the filament material and rare-earth long-afterglow luminescent materials as the optical source. Reversible thermochromic cresol red-boric acid (CB) pigment in the TFLs served as the luminescence conversion agent. The reflectivity curves and fluorescence spectra were recorded at 25 and 65 °C to investigate the thermosensitive characteristics of the TLFs. The results demonstrated that CB pigment functioned as a luminescent conversion agent that could convert the luminescence of rare-earth luminescent materials depending on the temperature. The luminescence of the TLFs can be converted from blue to fuchsia upon changing their temperature due to the structural transformation of the CB dye. The thermosensitivity can also be verified by observing the TLFs in water at 65 °C with the naked eye.

A color tuned highly emissive long-lasting phosphor PMMA/RECC@SAOED with warm-toned emitting color was prepared by coating a red-emitting coumarin fluorescent dye color converter (RECC) and PMMA on the surface of green emitting SrAl 2 O 4 :Eu 2+ , Dy 3+ (SAOED) phosphors. After being characterized by SEM, FT-IR spectra, photoluminescence (PL) spectra, CIE color coordinates and afterglow decaying curve, the results demonstrated the feasibility of the prepared RECC as the warm-toned color converter for the green-emitting SAOED. After being coated with color converter, the PL spectra of PMMA/RECC @SAOED consisted of two broad bands with two emission peaks at 520 nm and 610 nm, and the intensity of spectra in the range of (576–700) nm increased gradually with the increase of color converter content. The emitting color of the PMMA/RECC@SAOED could be easily controlled by adjusting the concentration of color converter, and it moved to yellow, orange and reddish when the concentration of color converter was added to 0.3%, 0.5% and 0.9%.

Noble metal nanoparticles (Pd, Ag, Pt, Au) with small and relatively uniform sizes were loaded on polydopamine nanospheres through in situ galvanic replacement reaction in aqueous solution. No additional reductant, surfactant or organic solvent was needed. X-ray photoelectron spectroscopy results revealed that the amount of quinone increased, while the amount of phenolic hydroxyl decreased on PDA nanospheres, indicating that the galvanic displacement reaction occurred between catechol groups and noble metal ions. The as-prepared PDA/Pd exhibited high catalytic activity and excellent stability in styrene hydrogenation. Moreover, PDA spheres retains the photo-thermal effect to serve as a nano-sized heater to accelerate the catalytic reactions under near-infrared illumination.

The Warburg effect is a metabolic hallmark of cancer. Tumor cells rapidly adjust their energy source to glycolysis in order to efficiently proliferate in a hypoxic environment, but the mechanism underlying this switch remains incompletely understood. Here, we show that hypoxia potently induces the down-regulation of miR-125a expression in hepatocellular carcinoma (HCC) cells and tumors. Furthermore, we demonstrate that miR-125a could decrease the production of lactate, the uptake of glucose, and the levels of ATP and reactive oxygen species (ROS) in HCC cells. We investigated the molecular mechanism through which miR-125a inhibits HCC glycolysis and identified hexokinase II (HK2) as a direct target gene of miR-125a. Finally, we revealed that the miR-125a/HK2 axis is functionally important for regulating glycolysis of HCC cell and progression of cancer in vitro and in vivo. In summary, our findings demonstrate for the first time that hypoxia-down-regulated miR-125a regulated HCC glycolysis and carcinogenesis by targeting hexokinase HK2, a key glycolytic enzyme for the Warburg effect, and add a new dimension to hypoxia-mediated regulation of cancer metabolism.

Most of the hollow carbon submicro-fibers (HCSFs) reported today are made from polyacrylonitrile (PAN) homopolymer. The obtained HCSFs are fragile due to the poor stabilization and spinnability of PAN. In this study, a bifunctional comonomer, β-methylhydrogen itaconate (MHI), was synthesized to prepare poly(acrylonitrile- co-β-methylhydrogen itaconate) [P(AN- co-MHI)] copolymer, which was used as a precursor to produce HCSF by coaxial electrospinning. The stabilization of P(AN- co-MHI) was studied by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR); the structure of HCSFs was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and field emission scanning electron microscopy (FE-SEM). The stabilization of P(AN- co-MHI) has been improved significantly by MHI with lower cyclization temperature, broadened peak and lower activation energy, which is beneficial to producing high-performance HCSFs. HCSFs with fine and uniform structures were obtained after stabilization and carbonization; the diameter of the HCSFs shrinks due to the elimination of N and the extra H. The diameter and wall thickness of HCSFs can be controlled simply by the feeding ratio of P(AN- co-MHI) solution/styrene- co-acrylonitrile solution. The resultant HCSFs can be bent more than 280° without breaking, which has potential applications in lithium-ion rechargeable batteries, supercapacitors, fuel cells, and catalyst.

A series of novel trimethylol propane monoesters were synthesized to prepare aqueous polyurethane dispersions (PUD), which were used as a polymer coalescent to assist the film forming of high T g polyacrylate latexes (PA). The effects of trimethylol propane monoester categories, NCO/OH molar ratios, soft segment contents, dimethylolpropionic acid (DMPA) contents, and diamine chain extenders on assistant-film-forming performance of PUD were investigated. The surface microstructures of PA/PUD blend latexes were also characterized with scanning electron microscopy (SEM) and transmission electron microscope (TEM). The results showed that the PUD prepared from trimethylol propane monolaurare (TMPLA) with long-chain alkyl groups displayed excellent assistant-film-forming ability. The assistant-film-forming ability of PUD was increased with decreasing of NCO/OH molar ratios and hard segment proportions. The optimum preparation process of better assistant-film-forming PUD was that isophorone diisocyanate (IPDI), polyether 220 (N220), trimethylol propane monoester (TMPLA) and adipic acid dihydrazide (ADH) as reactants, 1.5 of the NCO/OH molar ratios, 55/45 of the soft/hard segment mass ratio and 5% of ω (DMPA). The high T g polyacrylate latexes with PUD could form a continuous transparent film at 5 °C with 30 g L −1 of the volatile organic compounds (VOC) contents and display good film performance.

International audience; Prion-like transcellular spreading of tau in Alz-heimersD isease (AD) is mediated by tau binding to cell surface heparan sulfate (HS). However,t he structural determinants for tau-HS interaction are not well understood. Microarraya nd SPR assays of structurally defined HS oligosaccharides showt hat ar are 3-O-sulfation (3-O-S) of HS significantly enhances tau binding. In Hs3st1 À/À (HS 3-O-sulfotransferase-1 knockout) cells,reduced 3-O-S levels of HS diminished both cell surface binding and internalization of tau. In ac ell culture,t he addition of a3-O-S HS 12-mer reduced both tau cell surface binding and cellular uptake.N MR titrations mapped 3-O-S binding sites to the microtubule binding repeat 2(R2) and proline-richregion 2(PRR2) of tau. Taui so nly the seventh protein currently knownt or ecognize HS 3-O-sulfation. Our work demonstrates that this rare 3-O-sulfation enhances tau-HS binding and likely the transcellular spread of tau, providing an ovel target for disease-modifying treatment of AD and other tauopathies.

Solution-processable electrochromic polymers (ECPs) with high performance are urgently needed for extensive applications. Nevertheless, they suffer from slow switching speed because of low ionic conductivities. Herein, we present an effective strategy to improve the contrast and switching speed in ECPs via facile side-chain engineering. A novel electrochromic thieno[3,2-b]thiophene-based polymer (PmOTTBTD) is designed and successfully synthesized by introducing oligo(ethylene oxide) side chains with high ionic conductivity. Compared to the counterpart POTTBTD without modification by oligo(ethylene oxide) chains, PmOTTBTD demonstrates nearly double contrast (42 % vs. 24 %) with a fast oxidation switching process that just takes half of the time when detected under 400 nm, as well as much higher coloration efficiencies (e. g. 239.04 cm2 C-1 vs. 226.26 cm2 C-1 @ 400 nm and 314.04 cm2 C-1 vs. 174.00 cm2 C-1 @ 650∼700 nm). Besides, PmOTTBTD exhibits excellent stability with negligible decay after 3000 cycles. Our work suggests a facile strategy that could be adopted to realize high-performance ECPs via molecular design tuning.

The development of allergic disease starts prenatally, a vital period during which maternal exposure such as nutrient intake may modulate fetal and infant immune programming [1]. However, the role of various nutrients intake during maternal pregnancy, for instance, carotenoids, vitamin A and vitamin E, in the development of allergic diseases in the offspring is inconclusive. In this study, we aim to investigate the relationship between these nutrient levels in maternal plasma at delivery and subsequent offspring allergic outcomes in the first 5 years of life in the prospective mother‐offspring cohort study Growing Up in Singapore Towards healthy Outcomes (GUSTO).

This study aimed to verify the toxic effects of prenatal caffeine exposure (PCE) on the podocyte development in male offspring, and to explore the underlying intrauterine programming mechanisms. The pregnant rats were administered with caffeine (30 to 120 mg/kg⋅d) during gestational day (GD) 9 to 20. The male fetus on GD20 and the offspring at postnatal week (PW) 6 and PW28 were sacrificed. The results indicated that PCE caused ultrastructural abnormalities on podocyte, and inhibited the expression of podocyte marker genes such as Nephrin, Wilms tumor 1 (WT1), the histone 3 lysine 9 acetylation (H3K9ac) level in the Kruppel-like factor 4 (KLF4) promoter and its expression in the male offspring from GD20 to PW28. Meanwhile, the expression of glucocorticoid receptor (GR) and histone deacetylase 7 (HDAC7) in the fetus were increased by PCE. In vitro, corticosterone increased GR and HDAC7 whereas reduced the H3K9ac level of KLF4 and KLF4/Nephrin expression. KLF4 over-expression reversed the reduction of Nephrin expression, knockdown of HDAC7 and GR antagonist RU486 partially reversed the inhibitory effects of corticosterone on H3K9ac level and KLF4 expression. In conclusion, PCE caused podocyte developmental toxicity in male offspring, which was associated with corticosterone-induced low-functional programming of KLF4 through GR/HDAC7/H3K9ac pathway.

Small molecular organic electrochromic materials have gradually attracted the attention from academia. Although ester organic electrochromic materials show unique advantages such as significant color change, wide color adjustment range and low cost, their electrochromic mechanisms are still unclear, keeping their driving voltage and stability issues unsolved. In this article, the absorption spectra of phthalate derivatives under different conditions are calculated with time-dependent density functional theory to understand the influences on the electrochromic properties by the electronic and steric effects. By the increased conjugation and reduced steric hindrance, carbonyl linking group is found capable to enhance the absorption in the visible region and exhibit low driving voltages. Further, a new electrochromic compound is designed to improve the luminous effect and lower the driving voltage.

In order to obtain a red fluorescent fiber with long persistent performance, Sr2MgSi2O7:Eu2+, Dy3+ and Y2O2S:Eu3+, Mg2+, Ti4+ phosphors were prepared by high-temperature solid-phase method, then the phosphors and Rhodamine B were spun into the Polyacrylonitrile (PAN) through coaxial wet-spinning. The structure and morphology of samples were characterized by the X-ray diffraction, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and particle size analyzer. Fluorescent properties were studied based on photoluminescence spectroscopy and afterglow decay curve. The data show that Sr2MgSi2O7 has blue broadband emission due to the electronic transition of Eu2+, and the Y2O2S has red linear emission spectrum because of the electronic transition of Eu3+.The analysis results reveal that the excellent afterglow performance of Sr2MgSi2O7 plays a significant role in the secondary excitation. Rhodamine B was added in the coaxial fiber as a red light compensator through transferring the blue light to red fluorescence.

A kind of highly fluorescent cotton fibers, in which the luminescent carbon nanoparticles (CNPs) are generated in the lumen and the mesopores directly, have been prepared by the method of hydrothermal synthesis in situ using citric acid and urea as raw materials, and hexadecyl trimethyl ammonium bromide and tributyl phosphate as active agents. The CNPs/cotton fibers were characterized by thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscopy (XPS), respectively. The optical properties are investigated by fluorescence spectrofluorometry and PR-305 long afterglow phosphors tester. The results showed that the CNPs were self-assembled successfully in the lumen as well as in the mesopores of cotton fibers. The CNPs/cotton fibers could emit bright and colorful photoluminescence under excitation lights of different wavelengths. The afterglow decay process could be divided into fast decay and slow decay stages and the emission of CNPs/cotton fiber had two peaks at 450 nm and 570 nm respectively when the wavelength of excitation changed from 310 nm to 500 nm. The preparation of highly fluorescent cotton fibers by self-assembly method has great significance to the functionalization of cotton fibers.

Background/Aims: The apoptosis of activated hepatic stellate cells (HSCs) is the central event in the reversal of liver fibrosis. K63 de-ubiquitinated receptor-interacting protein (RIP)1 promotes apoptosis in tumor necrosis factor (TNF)-α signaling pathway. In the previous study, we have proved that indole-3-carbinol (I3C) could reverse different models of liver fibrosis in rats, but the mechanism is still unclear. Thus, the present research aimed to demonstrate the induction of I3C on apoptosis of HSCs and the underlying molecular mechanism. Methods: HSC-T6, an immortalized rat liver stellate cell line, was treated for 24 hours with 25, 50 and 100 µM of I3C. The apoptosis of HSC-T6 was analyzed by flow cytometric analysis, acridine orange staining and RT-PCR, respectively. K63 de-ubiquitination of RIP1 and the expression of ubiquitin ligases and deubiquitinases were analyzed by Co-IP assay and western blot. Knockdown of deubiquitinases was undertaken by small interfering RNA (siRNA). Results: The results of flow cytometric analysis indicated that the apoptotic rate of HSC-T6 was induced by I3C in a dose-dependent manner. Observation by acridine orange staining exhibited nuclear condensation and apoptotic bodies in I3C treated cells. Consistently, the expression ratio of Bax/bcl-2 was markedly increased by I3C. These results indicated that I3C could significantly induce apoptosis of HSC-T6 cells. Furthermore, Co-IP assay revealed K63 de-ubiquitination of RIP1 by I3C, associated with the induction of caspase 8. Although I3C had no effect on the expression of ubiquitin ligases cellular inhibitor of apoptosis 1/2 (cIAP1/2), the protein level of deubiquitinase cylindromatosis (CYLD) was significantly induced by I3C. Moreover, CYLD silencing reversed the pro-apoptosis induction effect of I3C and reduced the expression ratio of Bax/bcl-2 in HSC-T6 cells. Conclusion: These results demonstrated that I3C could induce apoptosis of HSC through RIP1 K63 de-ubiquitination by upregulating deubiquitinase CYLD.

Tetracene, one of the polyacene derivatives, shows eminent optical and electronic properties with relatively high stability. To take advantage of the intrinsic properties of the tetracene molecule and explore new semiconductors, herein, we report the design and synthesis of two novel p-channel tetracene derivatives, 2-(4-dodecyl-phenyl)-tetracene (C12-Ph-TET) and 2-phenyl-tetracene (Ph-TET). Top contact OTFTs were fabricated using these two materials as semiconductor layers, with charge mobilities up to 1.80 cm2 V−1 s−1 and 1.08 cm2 V−1 s−1, respectively. Our molecular modeling results indicate that the introduction of phenyl into tetracene can improve the efficient charge transport in electronic devices as a result of the increased electronic coupling between the two neighboring planes of the molecules. AFM images of the thermally evaporated thin films of these two materials show large grains, which correspond to the high mobilities of these devices. Consequently, the mobility of our OTFTs based on C12-Ph-TET is the highest for OTFTs based on tetracene derivatives reported to date. The single crystal analyses show the existence of π–π stacking interactions within the molecules with the introduction of mono-phenyl substituents, which is the main cause of the increased mobility. The impressive properties of these two materials indicate that the introduction of alkyl-phenyl and phenyl group could be an excellent method to improve the properties of the organic semiconductor materials.

Flower-like cobalt aluminum layered double hydroxide (CoAl-LDH) hollow microspheres were synthesized via a one-step solvothermal method without any template. An Ostwald ripening mechanism was proposed for the formation of hollow nanostructures. These flower-like CoAl-LDH hollow microspheres had a high surface area and exhibited excellent selectivity for anionic dyes. The limited space between LDH layers offered size selectivity for adsorbate molecules. For the small molecule methyl orange, the maximum adsorption capacity reached 816.0 mg g−1 under ambient conditions, while for larger molecules such as Eosin B, the adsorption capacity was only 95.1 mg g−1. All these features make the flower-like CoAl-LDH hollow microspheres an excellent adsorbent in water remediation.

The construction of core-shell structures through surface coating, and then making use of the synergistic effects between the core and shell to design and synthesize heterogeneous catalysts is a hot topic in the heterogeneous catalysis field. Developing a general coating route with functional shell materials is further highly desirable. Here we found that a poly(cyclotriphosphazene-co-4,4'-sulfonyldiphenol) (PZS) layer can be generally coated on various substrates with different components and morphologies, including metal oxides, noble metal nanoparticles, carbon materials and metal-organic frameworks (MOFs). In addition, the coating thickness could be well controlled through simply adjusting the amount of monomers. Taking advantage of the heteroatoms in the PZS layer and the synergistic effect between the core and shell, new methods for fabrication of co-doped hollow carbon shell catalysts and transition metal phosphide nanoparticles were developed. As a proof-of-concept application, the N, P, S-doped hollow carbon shells prepared by calcination of a ZnCo-ZIFs@PZS core-shell structure could act as a good carbo-catalyst for selective oxidation of C-H bonds in water.

White-light-emitting materials with high mobility are necessary for organic white-light-emitting transistors, which can be used for self-driven OLED displays or OLED lighting. In this study, we combined two materials with similar structures—2-fluorenyl-2-anthracene (FlAnt) with blue emission and 2-anthryl-2-anthracence (2A) with greenish-yellow emission—to fabricate OLED devices, which showed unusual solid-state white-light emission with the CIE coordinates (0.33, 0.34) at 10 V. The similar crystal structures ensured that the OTFTs based on mixed FlAnt and 2A showed high mobility of 1.56 cm2 V−1 s−1. This simple method provides new insight into the design of high-performance white-emitting transistor materials and structures.

Thieno[3,2-b]thiophene (TT) monomers end-capped with 3,4-ethylenedioxythiophene (EDOT) moieties are electropolymerized to form π-conjugated polymers with distinct electrochromic (EC) properties. Steric and electronic factors (electron donor and acceptor substituents) in the side groups of the TT core, as well as the structure of the polymer backbone strongly affect the electrochemical and optical properties of the polymers and their electrochromic characteristics. The studied polymers show low oxidation potentials, tunable from–0.78 to +0.30 V (vs. Fc/Fc+) and the band gaps from 1.46 to 1.92 eV and demonstrate wide variety of color palettes in polymer films in different states, finely tunable by structural variations in the polymer backbone and the side chains. EC materials of different colors in their doped/dedoped states have been developed (violet, deep blue, light blue, green, brown, purple-red, pinkish-red, orange-red, light gray, cyan and colorless transparent). High optical contrast (up to 79%), short response time (0.57–0.80 s), good cycling stability (up to 91% at 2000 cycles) and high coloration efficiency (up to 234.6 cm2 C–1) have been demonstrated and the influence of different factors on the above parameters of EC polymers have been discussed.