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In this study, the mechanical and electrical properties of Zn–Sb thin films with different Zn contents were focused; the corresponding improvement mechanism is also discussed. It is found that the maximum phase transition temperature of the film is 250 °C when the Zn content is about 50 at%. The crystallization activation energy of the film also reached a maximum of 4.549 eV. The micro-structure analysis result of these annealed films through XRD showed that when the Zn content is less than 50 at.%, the Sb crystallization firstly reduces the amorphous thermal stability of the material, while the film with the highest crystallization activation energy forms the ZnSb phase. Besides, adding N element greatly increases the resistance ratio of the film before and after the phase change and the phase change temperature point, the maximum temperature reaches 265 °C, and the resistance ratio reaches 104 orders of magnitude. The doping of N also increases the density of the deposited film. When the N content is less, some N elements fill the defects caused by physical deposition, increase the density of the film, and increase the phase transition temperature of the film. The N atoms in the film are more likely to bond with Zn when N content is high, forming a Zn–N bond, and even forming a Zn3N2 phase, so that the phase transition temperature of the film is lowered.

Optimized design of polymeric composites that are comprised of polymers and commonly used fillers forms one of the key focuses in this community since it may enhance the feasibility of real applications in industries. In this work, we produced three different epoxy composite coatings through filling the diamond, SiC, MoS2 and graphite. Then, the influence of these fillers on friction and wear performance of the composite coating is investigated. Comparison of the net epoxy (EP), the fracture toughness and young's modulus of the epoxy composite coatings (GME) can be 37.4 GPa and 4.3GPa, respectively, much higher than those of unfilled EP, i.e. 25.45 GPa and 3.75 GPa. More importantly, inclusion of multiple fillers can significantly reduce the wear rate and frictional coefficient of the GME. They are mainly because the graft treatment of the diamond and SiC dispersed uniformly in EP leads to a strong interface between the particles and matrix, making GME showing higher mechanical properties. Furthermore, due to the lubricant fillers-MoS2 and graphite, a continuous and thick lubricant film were observed on the worn surface of the GME, which can effectively decrease the friction heating and further damage to the matrix. Therefore, the strategy presented here is a valid method to create positive synergetic effect of different fillers, which can serve as an important guidance for rational design of the epoxy composite coatings towards in further industrial applications.

Pediatric post-transplant idiopathic liver fibrosis is an unexplained graft fibrosis that occurs in symptom-free children without acute rejection and surgical complications. Despite a lack of consensus on the subject, the development of pediatric post-transplant idiopathic liver fibrosis is believed to be the result of multiple potential factors, including ischemia-reperfusion injury, allogeneic acute and chronic rejection, viral hepatitis recurrence, opportunistic infection, and drug-induced liver damage. Among them, there is growing evidence that innate immunity may also have a unique role in this progression. This study reviews the features of pediatric post-transplant idiopathic liver fibrosis and discusses current studies illustrating the potential mechanisms of liver allograft tolerance induced by intrahepatic innate immunity, the role of components including Toll-like receptors (TLRs), interferons (IFN), dendritic cells (DC), natural killer cells (NK cells), NKT cells, neutrophils, and Kupffer cells, as well as their possibly relevant role in the development of pediatric post-transplant idiopathic liver fibrosis.

Limited by the relatively low adsorption capacity of inorganic nanomaterials for antibiotics , ultralong hydrogen titanate nanobelts (UHTNs) with a hollow structure and high surface area (442.21 m2 g−1) were synthesized to evaluate the feasibility as a potential adsorbent material for antibiotic removal. A batch of adsorption experiments were conducted by using norfloxacin (NFO), tetracycline (TC) and ofloxacin (OFO) as the model antibiotic molecules. The results indicate that the adsorption of antibiotics on UHTNs is better fitted to the pseudo-second-order kinetic model, and the UHTNs' maximum adsorption capacities calculated from the Langmuir isotherm model were 151.51 mg g−1 for TC, 111.73 mg g−1 for NFO, and 148.14 mg g−1 for OFO at pH = 7, which are far better than those of most reported inorganic adsorbent materials. In the adsorption process of tetracycline, the surface complexation between the adsorbent and TC contributed most to the adsorption; this has been elucidated by Fourier Transform Infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). In addition, because the UHTNs are up to tens of micrometers in length, they can be easily aggregated to form a network. Therefore, a novel paper-like, free-standing UHTN membrane was fabricated via a simple vacuum filtration method, which also exhibits good adsorption capacity.

Fenton-like processes have emerged as most promising techniques for generating reactive oxygen-containing radicals to deal with increasing levels of environmental pollution. Developing novel catalysts with simple manufacturing requirements, excellent activity levels, and stability remains a long-term goal in terms of practical application. So herein, a new polyethylene terephthalate (PET) non-woven fabric based composite catalyst has been fabricated, using radiation-induced graft polymerization of a functionalized group to chelate Co

Doping is an effective way to optimize the performance of thermoelectric materials. In order to investigate the effect of Bi doping on microstructures and thermoelectric properties of Ge0.90Pb0.10Te, a series of Ge0.90−xPb0.10BixTe compounds were prepared by a melting-quenching-annealing process followed by spark plasma sintering. The Bi doping on Ge site acts as an electron donor, which effectively optimized the carrier concentration from 1.1 × 1021 cm−3 to 3.5 × 1020 cm−3. Besides, the lattice distortions originated from Bi doping further promoted the solubility of Pb in the GeTe matrix, which have great advantage for obtaining lower thermal conductivity compared with pristine Ge0.90Pb0.10Te sample. Low lattice thermal conductivity of about 0.77 W/mK was obtained in Ge0.86Pb0.10Bi0.04Te owing to the additional lattice defects introduced by Bi doping. Consequently, the highest ZT of 1.1 was obtained in Ge0.86Pb0.10Bi0.04Te at 600 K with an average ZT of 0.6. These results have confirmed that Bi doing is an efficient way to boost the thermoelectric performance of GeTe-based alloys.

Fenton-like processes have emerged as most promising techniques for generating reactive oxygen-containing radicals to deal with increasing levels of environmental pollution. Developing novel catalysts with simple manufacturing requirements, excellent activity levels, and stability remains a long-term goal in terms of practical application. So herein, a new polyethylene terephthalate (PET) non-woven fabric based composite catalyst has been fabricated, using radiation-induced graft polymerization of a functionalized group to chelate Co2+ ions as heterogeneous catalysts in peroxymonosulfate (Oxone) activation. Several impact factors, including catalyst dosage, Oxone concentration, reaction temperature, pH value, Co2+ precipitation ratio (of Co@PET at different pH values), and highly concentrated NaCl have been investigated here. Notably, Co@PET has shown the lowest activation energy of any reported catalyst, for degrading RhB by activating Oxone. Interestingly, as experimental RhB and Oxone solutions were passed through single Co@PET sheets, the RhB was decomposed into a colorless solution in the penetration process. Based on radical trapping and quenching experiments, a channel was determined to dominate RhB degradation, and furthermore, Co@PET could be re-used for RhB degradation by activating Oxone. These results showed that Co@PET effectively provided improved Fenton-like catalytic performance and stability, and was suitable for practical applications.

Core–shell structure hybrids of carbon nanotubes (CNTs)/BaTiO3 (H-CNT-BT) and commercial multi-wall CNTs are respectively incorporated into poly(vinylidene fluoride) (PVDF) for preparing the composites near the percolation thresholds. A comprehensive investigation for CNT's dispersion and composite's conductivity is conducted between H-CNT-BT/PVDF and CNT/PVDF at different depths vertical to the injection's direction. Gradual increases of the conductivity in two composites are observed from the out-layer to the core part which infers an inhomogeneous CNT's dispersion in the interior of composites due to their migration under flow during the injection. However, the use of H-CNT-BT fillers with core–shell structure enables to reduce this inhomogeneous dispersion in the composite. Furthermore, the conductive network of CNTs in H-CNT-BT/PVDF is less sensitive to the thermal treatment than the one in CNT/PVDF composite, which infers the core–shell structure of hybrids can ameliorate the sensitivity of the conductive network. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45693.

Porous Mn 2 O 3 nanocubics, which were synthesized by a facile hydrothermal route followed by a calcination process, exhibited a specific capacitance of 191.1 F g −1 and a high rate capability with 58.6% specific capacitance retention even when the current density is increased by 50 times, and an excellent long-term cycle stability, and the fabricated simple symmetric supercapacitor was also fabricated and showed a good electrochemical performance, thus could be considered as a potential material for high-rate supercapacitors in some special applications that do not require a high capacitance.

A facile method to synthesize isomorphous MnO2@MnO2 core/shell nanostructures was developed for the first time by using MnO2 nanowires as seed crystals. These unique nanoarchitectures consisting of an isomorphous layer of β-MnO2 nanosheets well grown on the surface of β-MnO2 nanowires exhibit remarkable electrochemical performance with high capacitance and ultra long cycle life, i.e., nearly 92.2% retention after 20 000 cycles at a current density of 5 A g−1. The enhanced specific capacitance of the MnO2@MnO2 electrode is largely contributed by the capacitive processes including double-layer charging and Faradaic pseudocapacity. Particularly, these intriguing behaviors are strongly correlated with the unique isomorphous core/shell hierarchical configuration and high mechanical stability as well as the better interfacial structures between the MnO2 nanowire core and the ultrathin MnO2 nanosheet shell. In addition, it is demonstrated that the formation of defective and disordered regions throughout the whole core/shell architecture is the main cause for the unusual increased capacity during the early stages of cyclic charge/discharge.

The effects of secondary magnetic field originating from a permanent magnet on deposition rate, crystalline structure and photoelectric properties of Al-doped ZnO (AZO) films prepared by RF magnetron sputtering were systematically investigated. X-ray diffraction demonstrated that the films prepared using a secondary magnetic field were well aligned and textured along (0 0 2) orientation. SEM micrographs revealed that the grains became more compact and homogeneous with fewer defects in comparison to those grown by conventional magnetron sputtering (CMS). The deposition rate and lowest resistance of films prepared in the presence of a secondary magnetic field were 19.9 nm/min and 12.88 Ω/□, respectively. The average transmittance of all films in visible range was over 85% when the sputtering time was less than 60 min. The secondary magnetic field had a small influence on the transmittance of the films, but it caused a larger blue shift of the absorbance edge. Numerical simulations showed that the secondary magnetic field significantly changed the intensity and distribution of the transverse magnetic field in discharge space and caused a higher target current density.

International audience; Polymer composites with enhanced mechanical and functional properties are highly desired to develop light-weight function-integrated structures and devices. In this study, one kind of urchin-like hybrids was synthesized by in-situ growing CNTs on alumina microspheres (μAl2O3), and their reinforcing effects to epoxy were investigated in detail. It was found that as compared to pure epoxy the CNTs-μAl2O3 hybrids/epoxy composites possess highly improved electrical, dielectric, thermal and mechanical properties, achieving an enhancement as high as 5 orders of magnitude in the AC conductivity, 92% and 56% in the thermal diffusivity and thermal conductivity, respectively, and 26% in the Young’s modulus, when CNT mass fraction used was 2%. Detailed analyses and various microstructural characterizations were also conducted in order to understand the multiscale reinforcement effects. The significant enhancements observed are mainly due to the urchin-like structure and improved CNT dispersion in the epoxy matrix.

Ferritic steels containing copper have been studied as model systems for clusters/precipitate formation in reactor pressure vessel steels. The samples were aged at 400 °C for 4000 h and subsequently cold rolled to 30% reduction at room temperature. The microstructural characteristics of the samples were analyzed using high-resolution transmission electron microscopy. Direct evidence was found that the fivefold twinning occurs via simultaneous emission of two Shockley partial dislocations from two particular α-Fe/Cu interfaces, and then the pileup tips of the twofold twin.

By introducing a thin MgO/TiN buffer, layer-by-layer growth of ZnO epilayer on Si(111) has been realized. ZnO film directly on Si(111) substrate is poly-crystallized, whereas its quality could be significantly improved by inserting the buffer layer. In the case of employing the buffer layer, in situ reflection high-energy electron diffraction demonstrates that ZnO film is epitaxy and proceeding in the layer-by-layer growth mode. High-resolution X-ray diffraction indicates the relationship is ZnO(0002)//MgO(111)//Si(111) (out-of-plane) and the ZnO (0002) peak with the full width at half maximum of 1.3°. High-resolution transmission electron microscopy further validates that the in-plane epitaxial relationship is ZnO112¯0//MgO101¯//Si101¯. In photoluminescence, epitaxy ZnO film shows clear exciton-related peaks, which are believed to be of high quality. Copyright © 2014 John Wiley & Sons, Ltd.

We have reported a facile, template-free and effective electrochemical method to grow MnO2 ultrafine nanobelts on Ni foam. Electrochemical measurements showed that the MnO2 nanobelt electrode exhibited an enhanced specific capacitance of 509 F g−1 at 200 mA g−1 at 50 °C. More importantly, the specific capacitance of the MnO2 nanobelt electrode nearly has 91.3% retention after 5000 cycles with repeated heating and cooling in the temperature range of 0 to 50 °C, showing good high temperature-resistive long-term cycle stability.

Porous urchin-like MnCo2O4.5 hierarchical architectures (~4–6 μm in diameter) synthesized by a facile hydrothermal route followed by a calcination process exhibited a specific capacitance of 151.2 F g−1 at 5 mV s−1, outstanding rate capability with 83.6% specific capacitance retention even when the current density is increased 50 times and excellent long-term cycle stability at progressively varied current densities and could be considered as a potential mixed transition metal oxide material for high-rate supercapacitors in some special applications that do not require a high capacitance.

An effective magnetic-field-assisted hydrothermal synthesis was used to induce the growth of 2 × 2 tunnel MnO2 nanostructures for supercapacitor application. The as-fabricated electrode from the MnO2 nanostructures exhibited an enhanced specific capacitance of 306 F g−1 at 0.5 A g−1 and desirable cyclic stability, which considerably exceed the performance of MnO2 material prepared with and without a high magnetic field, making it a promising electrode material for supercapacitors.

Al and Ti doped ZnO thin films have been prepared by direct current magnetron cosputtering and thermal oxidation. The effects of these dopants on the microstructural, morphological and electrical properties of deposited films have been studied. The SEM demonstrated that the undoped ZnO thin film consisted of globular ZnO with particle size of ∼100 nm. Scanning electron microscopy EDX analysis confirmed that the dopant content in the ZnO–Al and ZnO–Ti thin film was 2·78 and 3·75 at-% respectively. The particle in the ZnO–Ti thin film was blocky or granular with thorns and its size was several micrometers, while the particle in ZnO–Al thin film was porous granular and the size was ∼2 μm. Resistance value testing and R/R calculation revealed that pure ZnO thin film had the highest gas sensitivity.

4 mol.% Y 2 O 3 stabilized ZrO 2 (YSZ) doped with various quantities of Gd 2 O 3 (G-YSZ) ceramic coatings were synthesized by electrophoretic deposition method, and followed by vacuum sintering and isothermally annealing at 1000 °C for different durations. X-ray diffraction (XRD) was used to investigate their phase composition. Scanning electron microscopy (SEM) was employed to examine their microstructure, while energy dispersive X-ray spectrometer (EDS) was used to assess composition of the composite coatings. The results indicated that YSZ coating was composed of tetragonal and monoclinic phase after vacuum sintering at 1000 °C for 2 h under vacuum ( −3 Pa). G-YSZ composite coatings were composed of tetragonal, monoclinic phase and a small amount of Gd 2 Zr 2 O 7 phase after vacuum sintering at 1000 °C for 2 h, whereas the content of monoclinic phase in G-YSZ composite coatings increased with increasing Gd 2 O 3 concentration. It was found that G-YSZ composite coatings were composed of tetragonal ZrO 2 phase, monoclinic ZrO 2 phase and cubic phase, whereas Gd 2 Zr 2 O 7 phase disappeared, after G-YSZ composite coatings were isothermally annealed at 1000 °C in air for 100 h. A detailed description of the results and their discussion was presented in the paper.

The TiN/Ni composite coatings were deposited on 7005 aluminium alloy by high speed jet electroplating and then processed with plasma transferred arc(PTA) scanning process. The microstructure, microhardness and friction coefficient of PTA scanning treated specimens were investigated. It is shown that the PTA scanning treated specimens have a rapidly solidified microstructure consisting of the uniformly distributed TiN phase and fine Al3Ni2 intermetallic phases. The composite coating has an average microhardness of approximately HV 800. The friction coefficient of PTA scanning treated specimens (oscillated at around 0.25) is considerably lower than that of TiN/Ni composite coating (oscillated at around 0.35). The corrosion behavior of the composite coating in 3.5% NaCl solution at room temperature was also determined using a potentiostat system. In comparison with the corrosion potential ϕcorr of −0.753 V for 7005 aluminium alloy, the corrosion potentials for TiN/Ti composite coating and PTA scanning treated specimen are increased by 0.148 V and 0.305 V, respectively. The PTA scanning treated specimen has the lowest corrosion current densityJcorr as well as the highest corrosion potential ϕcorr, showing an improved corrosion resistance compared with 7005 aluminium alloy.

Exchange coupling multilayer thin films, which combined giant magnetostriction and soft magnetic properties, were of growing interest for applications. The TbFe/FeAl multilayer thin films were prepared by dc magnetron sputtering onto glass substrates. The microstructure, magnetic, and magnetostrictive properties of TbFe/FeAl multilayer thin film was investigated at different annealing temperatures. The results indicated that the soft magnetic and magnetostrictive properties for TbFe/FeAl multilayer thin film compared with TbFe single layer film were obviously improved. In comparison with the intrinsic coercivity J H c of 59.2 kA/m for TbFe single layer film, the intrinsic coercivity J H c for TbFe/FeAl multilayer thin films rapidly dropped to 29.6 kA/m. After optimal annealing (350 °C×60 min), magnetic properties of H s =96 kA/m and J H c =16 kA/m were obtained, and magnetostrictive coefficient could reach to 574×10 −6 under an external magnetic field of 400 kAm −1 for the TbFe/FeAl multilayer thin film.

Plant NADP-malic enzyme (NADP-ME, EC 1.1.1.40) participates in a large number of metabolic pathways, but little is known about the NADP-ME family in woody plants or trees. Here, we characterized the tree Populus trichocarpa NADP-ME (PtNADP-ME) family and the properties of the family members. Five NADP-ME genes (PtNADP-ME1-PtNADP-ME5) were found in the genome of Populus. Semi-quantitative RT-PCR analysis show that the transcription levels of PtNADP-ME1 in lignified stems and roots are clearly higher than in other tissues, and PtNADP-ME2, PtNADP-ME3, PtNADP-ME4 and PtNADP-ME5 are broadly expressed in various tissues. PtNADP-ME gene expression was found to respond to salt and osmotic stresses, and NaCl salts upregulated the transcripts of putative plastidic ones (PtNADP-ME4 and PtNADP-ME5) significantly. Further, the NADP-ME activities of Populus seedlings increased at least two-fold under NaCl, mannitol and PEG treatments. Also, the expression of PtNADP-ME2 and PtNADP-ME3 increased during the course of leaf wounding. Each recombinant PtNADP-ME proteins were expressed and purified from Escherichia coli, respectively. Coomassie brilliant blue and NADP-ME activity staining on native polyacrylamide gels showed different oligomeric states of the recombinant PtNADP-MEs in vitro. Noticeably, the cytosolic PtNADP-ME2 aggregates as octamers and hexadecamers while the plastidic PtNADP-ME4 resembles hexamers and octamers. The four PtNADP-ME proteins except for PtNADP-ME1 have high activities on native polyacrylamide gels including different forms for PtNADP-ME2 (octamers and hexadecamers) or for PtNADP-ME4 (hexamers and octamers). High concentrations of NADP substrate decreased the activities of all PtNADP-MEs slightly, while the malate had no effect on them. The kinetic parameters (V (max), K (m), K (cat), and K (cat)/K (m)) of each isoforms were summarized. Our data show the different effects of metabolites (influx into tricarboxylic acid cycle or Calvin cycle) on the activity of the individual PtNADP-ME in vitro. According to phylogenetic analysis, five PtNADP-MEs are clustered into cytosolic dicot, plastidic dicot, and monocot and dicot cytosolic groups in a phylogenetic tree. These results suggest that woody Populus NADP-ME family have diverse properties, and possible roles are discussed.

Magnetostrictive multilayer films which consists of amorphous TbFe and FeB were prepared by dc magnetron sputtering onto glass substrates. The structure, magnetic and magnetostrictive properties of TbFe/FeB multilayer thin films were investigated at different annealing temperatures. The results reveal that the soft magnetic and magnetostrictive properties for TbFe/FeB multilayer thin films compared to TbFe single layer thin films were obviously improved. In comparison to the intrinsic coercivity J H c of 59.2 kA/m for TbFe single layer thin films, the intrinsic coercivity J H c for TbFe/FeBmultilayer thin films rapidly drops to 27.3 kA/m. After annealing at 350 °C for 60 min, the maximum saturation magnetostrictive coefficient of λs = 410×10−6 was obtained. The best low-field magnetostrictive coefficient could reach to 177×10−6 under 40 kA/m external magnetic field for the TbFe/FeB multilayer thin films after annealing at 250 °C for 60 min.