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In this study, spherical α-Fe2O3 prepared by the hydrothermal method was used as a template for the first time; LaFeO3 perovskite catalysts were successfully synthesized by the molten salt method, sol–gel method, and co-precipitation method.

It is of great significance for electromagnetic interference (EMI) shielding materials to fulfill long-lasting service requirements. Here, waterborne polyurethane (WPU) was coated on the surface of a silver nanowire (AgNW) network with sputter-deposited nickel nanoparticles (NiNPs) by dip-coating technology to improve their durability. After five dip-coating cycles, a WPU layer nearly coated the whole surface of the hybrid papers, and only a fraction of the metal filler is bare. The resultant hybrid papers exhibit an electrical conductivity of ∼3500 S m−1, remnant magnetization of 0.03 emu g−1, saturation magnetization of 0.10 emu g−1, and coercivity of 256 Oe. On the one hand, the presence of the WPU coating does not affect the shielding effectiveness (SE) of the hybrid papers; on the other hand, the WPU coating enhances the ability to resist tape peeling. Moreover, the resultant hybrid papers still maintain the original SE value (∼80 dB), even after exposure to air for 5 months owing to the isolation effect of the WPU coating, implying long-lasting durability. The results confirm that the obtained hybrid papers can meet the requirements of practical applications.

A novel anionic Cd(II)-based metal–organic framework, H2[Cd9(DDB)4(BPP)4(H2O)14]·4H2O·2DMA (1), was successfully obtained with a rigid carboxylate ligand 3,5-di(2′,4′-dicarboxylphenyl)benzoic acid (H5DDB) and a flexible pyridyl ligand 1,3-bis(4-pyridyl)propane (BPP). Complex 1 contains two-dimensional (2D) honeycomb structures and one-dimensional (1D) chain structures. The adjacent 2D structures are linked by strong intermolecular hydrogen bonds to form an ABAB 3D supramolecular structure, where the 1D chain structures traverse the channels of the 2D structures. Due to the anionic framework, Ln(III) ions (Ln = Eu and Tb) can be encapsulated in the framework of 1 by a post-synthetic modification process to obtain Ln(III)@1, where 1.09Eu(III)@1 (1a) and 0.658Tb(III)@1 (1b) can be obtained by soaking complex 1 in a Eu(NO3)3·6H2O or Tb(NO3)3·6H2O aqueous solution for 48 h. The liquid-state emission spectra of Ln(III)@1 can be tuned to be a white light emission by changing the Eu(III)/Tb(III) molar ratio in solution. Moreover, 1b can be used as a “turn-off” fluorescent probe for bilirubin with a low detection limit of 0.250 μM in phosphate buffer solution (pH = 7.4), which presents excellent sensitivity, high selectivity, and reusability. Furthermore, the devised fluorescent probe in serum also exhibits the fluorescence “turn-off” process with a low detection limit of 0.279 μM, and the recovery rate of bilirubin is 99.20–101.9%. The possible mechanisms of the fluorescence “turn-off” process can be explained by resonance energy transfer, and the weak interaction between 1b and bilirubin.

One of the main mechanisms of bacterial decolorization and degradation of azo dyes is the use of biological enzymes to catalyze the breaking of azo bonds. This paper shows the expression and properties of a novel azo reductase (hybrid-cluster NAD(P)-dependent oxidoreductase, accession no. A0A1S1BVU5, named BVU5) from the bacterial flora DDMZ1 for degradation of azo dyes. The molecular weight of BVU5 is about 40.1 kDa, and it contains the prosthetic group flavin mononucleotide (FMN). It has the decolorization ability of 80.1 ± 2.5% within 3 min for a dye concentration of 20 mg L

Inverted perovskite solar cells (PSCs) have recently gained increasing attention because of the long operation lifetime achieved. However, bathocuproine (BCP): a commonly used buffer layer in inverted PSCs, is experimentally confirmed by us to show fast aggregation at the temperature of 85 °C, which is the protocol temperature required by the International Electrotechnical Commission (IEC) standard. This thermal instability of the BCP interfacial layer makes long-term thermal stability of inverted PSCs questionable. Simply removing or replacing it can directly lead to an inferior PCE of a device. We solve this problem by removing the BCP layer and simultaneously increasing the thickness of C60, which obtains a high efficiency of 18% comparable with the device with BCP. This is possibly attributed to the extended migration path of carriers from C60 to metal electrode Ag, consequently reducing the carrier accumulation at the interface. In addition to the interfacial modification, the addition of ionic liquid: BMIMBF4 into perovskite can further improve a device's thermal stability by its effective suppression of perovskite decomposition. The devices with 0.4 mol% of BMIMBF4 exhibit promising thermal stability by retaining 80% of their initial PCE after thermal aging of 400 h at 85 °C.

Excessive accumulation of free radicals in the body can cause liver damage, aging, cancer, stroke, and myocardial infarction. Anastatin B, a skeletal flavonoid, was reported to have antioxidant and hepatoprotective effects. Anastatin B derivatives, compound 1 and 2, were synthesized by our group previously. In this study, their antioxidant activity and hepatoprotective mechanism were studied using chemical evaluation methods, a cellular model of hydrogen peroxide (H2O2)-induced oxidative damage, and a mouse model of carbon tetrachloride (CCl4)-induced liver injury. Results from the chemical evaluation suggested that both compounds had good antioxidant power and radical scavenging ability in vitro. MTT assay showed that both compounds had cytoprotective activity in H2O2-treated PC12 cells. Moreover, their hepatoprotective activities evaluated using a mouse model of CCl4-induced liver injury that compared with the model group, pretreatment with compound 1 and 2 significantly decreased alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), and malondialdehyde (MDA) levels; reduced the liver tissue damage; and increased glutathione content. However, compound 2 was a more effective hepatoprotectant than compound 1 was. Finally, the amount of TNF-α and cytochrome P450 2E1 (CYP2E1) were significantly downregulated in compound 1 and 2 pretreatment groups. Collectively, our findings demonstrate that both compounds have potential antioxidant activity and hepatoprotective effect in vitro and in vivo. Further chemo-biological study and investigation of the compounds' enzymatic targets are ongoing.

This work reports the synthesis of coaxial carbon@NiMoO4 nanofibers for supercapacitor electrode applications. Thin NiMoO4 nanosheets are uniformly coated on the conductive electrospun carbon nanofibers by a microwave assisted hydrothermal method to form a hierarchical structure, which increases the porosity as well as the conductivity of the electrode. The thickness of the NiMoO4 can be easily adjusted by varying the precursor concentrations. The high specific surface area (over 280 m2 g−1) and conductive carbon nanofiber backbone increase the utilization of the active pseudocapacitive NiMoO4 phase, resulting a high specific capacitance of 1840 F g−1.

In this study, a newly screened mixed bacterial flora DDMY2 had high decolorization capacity for anthraquinone dye reactive blue 19 (RB19) and the decolorization efficiency of 300 mg L−1 RB19 could reach up to 98% within 48 h in the presence of tea residue. Results indicated that RB19 could be efficiently decolorized by flora DDMY2 in wide ranges of pH values (5.0–9.0), temperatures (30–40 °C) and initial dye concentrations (50–500 mg L−1) under the activation of tea residue. Concentration of tea residue had been proved to significantly impact the decolorization performance. UV-vis spectrophotometry, Fourier transform infrared spectrometry and liquid chromatography/time-of-flight/mass spectrometry analysis showed three identified degradation products and the possible degradation pathway of RB19 was speculated. High-throughput sequencing analysis revealed the community structures of bacterial flora before and after domestication by tea residue. Based on the result, it was inferred that unclassified_o_Pseudomonadales, Brevibacillus, Stenotrophomonas and Bordetella activated by tea residue were responsible for the excellent decolorization performance. Results of this research deepen our understanding of the biodegradation process of anthraquinone dyes by bacterial flora and broaden the knowledge of utilizing tea residue as a bioactivator in biological treatment.

Rolling circle amplification (RCA) and rolling circle transcription (RCT) can be used to fabricate various structures and organize functional materials for biological applications. The full understanding of the interactions between RCA/RCT-derived structures and live cells is urgently demanded. Here, we present a label-free fluorescent strategy to study the intracellular location and stability of RCA-based DNA flowers in live cells. The DNA flower structures are co-assembled with carbazole-based biscyanine fluorophores, which are DNA detecting molecules and characterized by restriction of intramolecular rotation (RIR) induced strong fluorescent emission. When biscyanine molecules are encapsulated in the DNA flowers via electrostatic attraction, these confined RIR dyes can produce strong luminescent emission. Using this advantage, we use the RIR enhanced technique for direct visualization of the distribution and degradation of DNA flowers in live cellular systems. Our current research could be adapted to other advanced DNA-based materials, providing a new strategy to fabricate fluorescent DNA materials and realize controllable release of payloads.

This paper studies the impacts of five key synthesis parameters of zeolitic imidazolate framework-8 (ZIF-8) in an aqueous solution, namely zinc resource, pH value, temperature, reaction time, and the concentration of water in the ligand (H2O/Hmim). It was found that the crystallization of ZIF-8 samples is strongly impacted by these synthesis parameters. ZIF-8 synthesized at a temperature of 85 °C, reaction time of 5 min, and pH value of 11.4 had a large special surface area and pore volume, and thus had a high CO2adsorption capacity of 3.04 mmol g-1. The CO2capture capacity remained constant after eleven consecutive adsorption-desorption experiments. Further applications of the hydrothermal synthesis method are promising considering the remarkable CO2adsorption capacity and cyclic regeneration ability. © 2017 The Royal Society of Chemistry.

Photocatalytic degradation of imidazolium ionic liquids using dye sensitized TiO2/SiO2composites Huang, Lirong1; Yu, Yinghao1 Email author ceyhyu@scut.edu.cn; Fu, Chao2; Guo, Haiyang1; Li, Xuehui1 Source: RSC Advances, v 7, n 51, p 32120-32125, 2017; E-ISSN: 20462069; DOI: 10.1039/c7ra04939k; Publisher: Royal Society of Chemistry Author affiliations: 1 School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou; 510641, China 2 SINTEF Energy Research, Trondheim; 7465, Norway Abstract: Ionic liquids (ILs) are widely applied in diverse fields, however, ILs bring considerable challenges to the ecosystem when exposed to the environment due to their cytotoxicity and high chemical stability. It is thus increasingly important to investigate measures for the degradation of IL wastes in industrial processes. This paper presents the preparation of dye-sensitized photocatalysts (DCQ-TiO2/SiO2) and their applications in the degradation of 4 imidazolium ILs (1-butyl-3-methylimidazolium bromide, [BMIM]Br; 1-butyl-3-methylimidazolium tetrafluoroborate, [BMIM]BF4; 1-butyl-3-methylimidazolium hexafluorophosphate, [BMIM]PF6; 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [BMIM]NTf2). The photocatalysts are prepared through in situ incorporation of TiO2into silica matrices and sensitization with 2,9-dichloroquinacridone (DCQ). The photocatalysts are then characterized with N2adsorption-desorption isotherm measurements, transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), elemental analysis and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). The results show that these photocatalysts exhibit high catalytic activities when they are applied in the degradation of imidazolium ILs. The degradation efficiency for [BMIM]Br can reach up to 95% under simulated sunlight irradiation in 180 minutes. The photodegradation intermediates of [BMIM]+are identified as harmless and easily biodegradable moieties. © 2017 The Royal Society of Chemistry

ReB2-type MnB2 has always been considered to be the ground-state structure of MnB2. However, subsequent theoretical study has revealed that this structure is easy to decompose into elemental Mn and B under ambient conditions, which motivated us to look for a stable MnB2 structure at high pressures. Using structure prediction algorithm USPEX and density functional theory calculations, we found a stable multi-layered MnB2 structure with space group Immm at high pressure. The calculated hardness of Immm-MnB2 is 22.5 GPa, which makes it a potential hard multifunctional material along with its conductive and magnetic properties. The hexagonal graphene-like boron networks of Immm-MnB2 contribute to its hardness and stability.

This work reports the synthesis of coaxial carbon@NiMoO

Excessive accumulation of free radicals in the body can cause liver damage, aging, cancer, stroke, and myocardial infarction. Anastatin B, a skeletal flavonoid, was reported to have antioxidant and hepatoprotective effects. Anastatin B derivatives, compound 1 and 2, were synthesized by our group previously. In this study, their antioxidant activity and hepatoprotective mechanism were studied using chemical evaluation methods, a cellular model of hydrogen peroxide (H

Early osseointegration plays a crucial role in determining the therapeutic efficacy of orthopedic implants. Some factors responsible for early osseointegration, such as inherent mechanical properties and surface topology of implants, are well-characterized. However, the synergistic effects of elastic modulus and surface topology of implants on the osteogenic differentiation of stem cells and early osseointegration have not been thoroughly investigated. In this study, the titanium (Ti) and β-titanium alloy Ti–24Nb–4Zr–8Sn (TNZS) were used to evaluate the synergistic effects of elastic modulus and surface topology on the biological performance of these materials in vitro and in vivo. Scanning electron microscopy imaging confirmed the presence of a micro-scale porous oxide layer on the Ti and TNZS surfaces upon treatment with microarc oxidation (MAO), which resulted in increased surface roughness, enhanced surface wettability and favourable mechanical properties. As compared with Ti-MAO, the TNZS-MAO samples with lower elastic modulus displayed increased cell attachment, alkaline phosphatase activity, collagen secretion, osteogenic marker expression, and mineralization of rat bone marrow mesenchymal stem cells. Upon implantation in rat femoral condylar defects, an inherently low elastic modulus could cooperatively accelerate early osseointegration and maturation of trabecular bone after 4 weeks implantation with the MAO modified surface. These results demonstrated that elastic modulus and the surface micro-scale topographical structure of Ti alloy implants have a synergistic effect on their osseointegration.

The presence of estrogenic/antiestrogenic chemicals in textile dyeing wastewater has been well demonstrated according to previous studies. However, the characteristics of estrogenic/antiestrogenic activities during conventional biological treatment have been poorly investigated. In this study, the yeast two-hybrid assay (YES) was used to evaluate the agonistic and antagonistic estrogen activities during the anoxic/aerobic treatment of textile dyeing wastewater. The results indicated that the estrogenic activity of the textile dyeing wastewater was negligible throughout the anoxic/aerobic treatment, but the antiestrogenic activity increased obviously after the aerobic treatment. By fractionating the dissolved organic matter (DOM) in wastewater into different fractions, it was found that hydrophobic acids (HOA) and hydrophobic neutrals (HON) were the key fractions involved in increasing antiestrogenic activity of the wastewater during anoxic/aerobic treatment. Furthermore, the fluorescence spectroscopy analysis on wastewater samples and their fractions of soluble organic compounds suggested that HOA and HON fractions contained more humic/fulvic acid in aerobic effluent than that in anoxic effluent, which could mask estrogenic activity in aerobic effluent.

In this paper, we report the design, synthesis, and dielectric properties of a novel photosensitive polyurethane dielectric film used in organic thin-film transistors (OTFTs). The novel photosensitive polyurethane dielectric film is readily fabricated by spin coating followed by curing under UV light. The film exhibits excellent insulating properties, smooth surface, and excellent photosensitive properties. The bottom-gate top-contact para-sexiphenyl (p-6P)/vanadyl-phthalocyanine (VOPc) OTFTs with photosensitive polyurethane films as the dielectric layer exhibit excellent performance with a mobility of 0.13 cm2 V−1 s−1, on/off ratio of 104 and ultralow leakage.

Catalytic process is the key process for many chemical industries. In this study, a novel heterogeneous Pd (CMH–Pd(0)) has been prepared by the deposition of palladium nanoparticles (Pd NPs) onto the surface of carboxymethyl functionalized hemicelluloses using ethanol as solvent and in situ reducing agent. The as prepared catalyst was characterized by TEM, HR-TEM, XRD, FT-IR, TGA and XPS. The loading level of Pd in the CMH–Pd(0) catalyst was 0.38 mmol g−1. The catalyst showed high catalytic activity and versatility towards Heck coupling reactions under aerobic conditions and could be readily recovered and reused in at least five successive cycles without obvious loss in activity. The catalyst is promising for its renewability, environmental benefits, efficient catalytic activity, mild reaction conditions, simple product work-up and easy catalyst recovery.

Mesoporous alumina with different morphologies was synthesized via thermal decomposition of the Al-based metal–organic frameworks (Al-MOFs) MIL-110 and MIL-100, in which Al-MOFs were used as the Al source and precursor. The hexagon rod-shaped and octahedron-shaped alumina products with morphology retained from their precursors were obtained and characterized. The results show that the construction of Al-MOFs, especially the aluminium building units plays a key role in the textural structure of the obtained alumina products. Besides, the differences in textural properties as well as the possible formation mechanism of the final alumina products are well explained by taking into account thermal behaviour and intrinsic structure features, especially the aluminium building units, of the Al-MOFs precursors. This work presents an easy new method to produce alumina with tailored morphology, tunable texture and microstructure, which is also an operational method fit for other metal oxide materials.

A simple label-free photoelectrochemical (PEC) platform was developed based on magnetic CdS–Fe3O4 nanocomposites and used for detection of aflatoxin B1 (AFB1). CdS quantum dots (QDs) were successfully assembled on mesoporous Fe3O4 NPs via covalent binding and employed as the photoactive materials on the surface of screen-printed electrode (SPE). H2O2 was employed as a sacrificial electron donor for scavenge photo-generated holes in the valence band of CdS QDs. Anti-aflatoxin B1 (anti-AFB1) was conjugated onto CdS–Fe3O4 nanocomposites modified SPE by using the classic EDC coupling reactions between the carboxy group (–COOH) groups on the surfaces of the TGA capped CdS QDs and the amino group (–NH2) groups of the antibody (Ab). The concentrations of AFB1 were measured through the decreased photocurrent resulting from the increased steric hindrances due to the formation of the immunocomplex. Under the optimal conditions, the PEC biosensor for AFB1 determination exhibited a linear range from 0.01 ng mL−1 to 80 ng mL−1 with a detection limit of 5.0 pg mL−1. Besides, the PEC biosensor has been applied in the corn samples detection. The proposed PEC biosensor is simple, sensitive, fast and stable, which opens up a new promising PEC platform for other small molecules analysis.

Pb(Zr0.52Ti0.48)O3 (PZT) nanofibers with diameters of 150–200 nm are prepared via electrospinning and used as dielectric fillers in poly(vinylidene fluoride) (PVDF)-based composite films. Highly flexible polymer composite films are fabricated with a solution cast method. Enhanced dielectric constants are obtained at low volume fraction of PZT nanofibers. The orientation of PZT nanofibers perpendicular to the external electric field gives rise to improved dielectric breakdown strength. A subsequent uniaxial stretching of the composite films leads to higher crystallinity and breakdown strength of the polymer composites, which is favorable for the polarization of the nanocomposites at higher electric fields. Enhanced ferroelectric properties, i.e., higher saturated and remnant polarization, are obtained in these composite films. A high piezoelectric coefficient (d33) of ∼87.4 pm V−1 is also achieved for the polymer composite films filled with only 2.4 vol% of PZT nanofibers. The results show that the PZT/PVDF composite films have potential applications in piezoelectric sensors, and even piezoelectric actuators.