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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.

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.

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.

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.

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.

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.

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.