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Epoxy coatings play an important role in preventing the corrosive medium penetrating into the base metal, but improving its durability in harsh environments is still a challenge. Nanomaterial introduced in epoxy coatings is an effective improvement measure, especially, the use of two-dimensional nanomaterial can effectively block the corrosion medium. In this paper, we use two-dimensional molybdenum disulfide (MoS2) hybrid materials as nanofiller to improve the corrosion resistance of epoxy coatings. MoS2 hybrid materials were obtained by an effective method based on self-oxidation of dopamine and functionalized silane (KH560) grafting. The poly(dopamine) and epoxy groups on the surface of MoS2 enhanced the interaction with EP matrix. The anticorrosive performance of composite epoxy coating with the different content of MoS2 hybrid materials was investigated in detail. An appropriate content (0.8 wt%) in the epoxy coating was obvious to improve its anti-corrosion performance.

With the increasing presence and adoption of the smart device in the Internet of Things (IoT), the service recommendation is becoming more and more important. In this paper, we proposed a service recommendation scheme based on the mass diffusion dynamic tag tripartite graph. We extracted the users' habit features of using the IoT device service as the dynamic tag and then built the tripartite graph. Through the positive and backward mass diffusion on the tripartite graph, we got the resource value of the service. We finally obtained the recommendation list through the comprehensive calculation of the energy state, the user similarity, the bearing capacity, and the service resource value of the mass diffusion results. The experiments showed that the recommendation precision of the service recommendation scheme we proposed was at least 12% higher than the other algorithms.

A series of biodegradable polymers was prepared by solution co-precipitation of poly(para-dioxanone) (PPDO) and poly(lactic-co-glycolic acid) (PLGA) in various blend ratios. Samples were compression-molded into bars using a platen vulcanizing press. The miscibility, thermal and mechanical properties of the materials were investigated using differential scanning calorimetry (DSC), polarized optical microscopy, and scanning electron microscopy (SEM). Dynamic contact angle was used to characterize the water wettability of PLGA/PPDO blends. The mechanical properties of blends and pure polymers were measured by tensile tests. The position of the glass transition temperatures (T g ) was dependent upon composition. When 10 % PLGA was added into PPDO, the DSC curve revealed only one T g (−7.35 °C) which was located between the T g values of PPDO and PLGA. When 20 % PLGA was added into the blend, two independent T g values for PPDO/PLGA blends were observed, and such characteristics improved further upon addition of 30 % PLGA. SEM images of fractured surfaces displayed evidence of the morphology of PPDO/PLGA blends that were consistent with the DSC results. Hence, a relationship was found between homogeneity and the contents of PLGA in the blend. The compatibility of the blends increased with addition of small amounts of PLGA, followed by a leveling-off at higher content.

Self-healing coatings, possessing an “active healing” ability to repair physical damage and to prolong the life of coating without external intervention, are of current interest. Herein, a novel self-healing coating, by using aspartic acid intercalated layered double hydroxide (AA-LDH) @ reduced graphene oxide (RGO) as filler within epoxy has been demonstrated. The corrosion protection performance and self-healing ability of composites coatings have been investigated via electrochemical impedance spectroscopy (EIS) and salt spray test. The AA-LDH@RGO/epoxy exhibits excellent corrosion resistance owing to the high barrier properties of RGO for corrosive ions. Moreover, the epoxy loaded with AA-LDH@RGO shows outstanding self-healing performance, attributing to the release of AA from LDH on the basis of the ion exchange performance, thus leading to formation of AA-Fe-AA compounds at the coating/steel interface. The results clarified that the addition of AA-LDH@RGO increases the impedance of the epoxy resin from 6.437 × 106 to 2.112 × 109 Ω cm2, and effectively extends the epoxy coating failure time to 40 days.

Molybdenum disulfide (MoS2) with the defect-rich sites was prepared, and further functionalized by epoxy groups, obtaining the hybrid materials (KH560-MoS2). The microstructure and composition of KH560-MoS2 were characterized by SEM, TEM, XRD, Raman, and XPS, which those results demenstrated that KH560-MoS2 was successfully modified by gamma-(2, 3-epoxypropoxy) propyl-trimethoxy silane (KH560) on the defect-rich MoS2 nnaosheets. In addition, KH560-MoS2 nanosheets were introduced into epoxy coating. Moreover, the influence of the amount (0 wt%, 0.2 wt%, 0.5 wt%, 0.8 wt%, 1.0 wt%, 1.5 wt%) of KH560-MoS2 on corrosion resistance of epoxy coating was studied by electrochemical impedance spectroscopy (EIS) and salt spray test, which showed that epoxy coating with the 0.8 wt% KH560-MoS2 exhibited the remarkable superiority in enhancing the anticorrosion performance.

Graphene oxide (GO), BiOBr and graphene–BiOBr nanosheets composites (BiOBr–RG) were synthesized and characterized. It can be found that except for BiOBr nanosheets with pure tetragonal phase were grown uniformly on the graphene surface, little graphene layer also can load on the surface of BiOBr evenly. And we found that the graphene can change the conduction band (CB) and valence band (VB) of BiOBr toward enhanced photocatalytic activity for reactive oxygen species (ROS) generation than that of BiOBr under visible-light irradiation.

Graphene oxide (GO), tungsten trioxide (WO3) and graphene–WO3 nanobelt composites (GW) were synthesized and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), UV–vis diffuse reflection spectra (DRS) and X-ray photoelectron spectroscopy (XPS) valence band spectra. We demonstrated that the graphene can elevate the conduction band of WO3 toward photocatalytic reduction of CO2 into hydrocarbon fuels under visible-light irradiation. And the photocatalytic activity of GW is higher than that of GO, WO3 and P25 TiO2.

Uniform anatase TiO 2 microspheres with a high percentage of exposed {001} facets have been successfully synthesized by a one-step hydrothermal strategy in the presence of H 2 O 2 and (NH 4 ) 2 CO 3 solution. The as-synthesized anatase TiO 2 microspheres with exposed {001} facets exhibited higher photocatalytic selectivity for degradation of methylene blue and methylene orange mixed solution under UV light irradiation at room temperature than anatase TiO 2 microspheres without {001} facets exposing and P25 TiO 2 .

Ag2O/Ag3PO4 heterostructures photocatalysis was prepared for the first time. Photocatalytic tests displayed that the Ag2O/Ag3PO4 heterostructures possessed a much higher degradation rate of methyl orange and phenol than pure Ag3PO4 under visible light. The enhanced photocatalytic activity could be attributed to effective separation of photogenerated carriers driven by photoinduced potential difference generated at the Ag2O/Ag3PO4 heterojunction interface. Repetitive tests showed that the Ag2O/Ag3PO4 heterostructures maintained high stability over several cycles, and it had better regeneration capability under mild conditions. The good stability could be attributed to the protection of insoluble Ag2O nanoparticles on the surfaces of Ag3PO4 crystals in aqueous solution.

The poly(para-dioxanone) (PPDO)/poly poly (dl-lactide) (PDLLA) blends containing various contents of compatibilizer (0, 1, 3, 5, 10 %) were prepared by solution co-precipitation, which were dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) to form 10 % wt/vol solutions. Then in vitro hydrolytic degradation of PPDO/PDLLA blends containing poly (dl-lactide-co-para-dioxanone) (PLADO) as the compatibilizer was studied by the changes of weight loss, water absorption, thermal properties, surface morphology and mechanical properties of samples in phosphate buffered saline (pH 7.44) at 37 °C for 8 weeks. During the degradation, the weight loss and water absorption increased significantly for all blends, whereas hydrolysis rate of blends varied with the blend composition. The samples’ glass transition temperature decreased notably, while the degrees of crystallinity increased. Compared with uncompatibilized PPDO/PDLLA blends, PPDO/PDLLA blends with compatibilizer exhibited higher hydrolysis rate. The results suggested that the compatibilizer (PLADO) accelerated the hydrolysis rate of PPDO/PDLLA blends during the degradation.

Gold loaded Bi2WO6 (Au/Bi2WO6) nanosheet-based microspheres were prepared via a hydrothermal method combined with an in-situ reduction approach. The products were characterised by scanning electron microscopy, a high-resolution transmission electron microscope, X-ray diffraction, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and UV–vis diffuse reflectance. The characterisation results revealed that it was the Au nanoparticles deposited on Bi2WO6 microspheres. A photocatalytic test for the degradation of phenol proved that Au loading was an effective means to enhance the photocatalytic activity of Bi2WO6 nanosheet-based microspheres under visible-light irradiation (λ > 420 nm). The photocatalytic mechanism over the Au/Bi2WO6 was analysed by active species trapping experiments. The main active species •OH for the photocatalytic test was produced by two pathways, that is, photogenerated holes oxidised water molecules to form •OH (oxidative pathway), and O2 captured the photogenerated electron to generate •O2 − and subsequently produce •OH (reductive pathway).

Because of the sizes of the pore throat are on the nanometer scale, nanoparticles with sizes on the nanoscale have been developed as candidates for plugging materials during drilling in shale formation. In this study, Fe3O4 nanoparticles were prepared by a coprecipitation method, and then, Fe3O4/poly(acrylic acid) (PAA) hybrid nanoparticles were obtained through the modification of the Fe3O4 nanoparticles with PAA. The hybrid nanoparticles were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, and thermogravimetric analysis. The magnetic properties, salt tolerance, and compatibility with sulfomethylated phenolic resin of the nanoparticles were studied. The plugging properties of the Fe3O4/PAA hybrid nanoparticles were evaluated by filtration testing of the filter cakes at ambient temperature and 80 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43967.

Rutile TiO 2 nanoparticle modified anatase TiO 2 nanorods (TiO 2 -RMA) with {010} facets exposing structure were one-pot synthesized and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and fast-Fourier transform pattern (FFT). It showed high photocatalytic reduction CO 2 conversion than pure anatase TiO 2 nanorods. The total yield of CH 4 of TiO 2 -RMA obtained in the experiment after 8 h of continuous irradiation was 18.9 μmol/g. In comparison, TiO 2 -A shows low photocatalytic activity toward methane production 10.3 μmol/g after 8 h UV light irradiation. And the photocatalytic mechanism of TiO 2 -RMA also was discussed.

Poly(para-dioxanone) (PPDO)-based composites have been prepared by blending PPDO with three different types of CaCO3 particles, CC1 (nano-CaCO3), CC2 (CaCO3 whisker), and CC3 (silane-coated CaCO3 whisker). The effects of particles size, interface adhesion, and crystallinity of composites on mechanical properties were discovered through analysis of the morphology of fracture surfaces, thermal characteristics, and crystalline structure. DSC revealed that the CaCO3 particles acted as a nucleating agent and promoted crystallinity of PPDO. The effect of CaCO3 particles on crystallization of PPDO was clearly revealed by using the nucleating efficiency. Smaller size particles exhibit greater nucleating efficiency. Adhesion between PPDO and the CaCO3 particles plays major roles on the mechanical properties of composites. The tensile strength of PPDO was improved over 54%. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers

N, C-codoped BiOCl (BiOCl–NC) flower-like hierarchical structures were synthesised by an one-pot solvothermal process and characterised by X-ray diffraction patterns, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance spectra, transmission electron microscopy and high-resolution transmission electron microscopy. As-synthesised BiOCl–NC showed higher photocatalytic activity in an aqueous RhB photodegradation system than pure BiOCl under visible light irradiation. The trapping experiments of active species during the photocatalytic reaction showed that the photocatalytic degradation of organic pollutants in the BiOCl–NC system proceeds through direct hole transfer and O2•− rather than •OH.

About 300 μm thickness uniform thermal barrier coatings (TBCs) were deposited on the 1Cr18Ni9Ti samples by solution precursor plasma spray (SPPS). The analysis methods, such as TEM, SEM, and XRD were used to characterize the coatings in the aspects of microstructure and phase compositions. The samples were quenched from 1121 °C to room temperature by forced-air to measure the thermal cycling capability. Coatings density were measured by means of water displacement. The experimental results show that grain size of the SPPS TBCs is about 30 nm with desired tetragonal phase ZrO2, and the SPPS TBCs(with 16% porosity) consist of arcuate pores, gelatin and melted particles. The hardness of the coatings is HR45Y38.5 and bond strength between coatings and substrates is 24.2 MPa. The thermal shock test show the coatings have a average life of 500 cycles which is about 2.5 times than that of conventional air plasma spray (APS) TBCs.

In this paper, we propose a habit-based SWRL generation and reasoning approach in smart home. Definition and recognition of habits of daily living can provide humanized smart home for assisted living application, especially for people with memory deficits. This paper presents Recognizing Habit of Daily Living(RHDL) by discovering and monitoring smart home context information. The habit and habit association of using electrical appliances are defined explicitly for the first time. The generation rules between habit/complex habit and SWRL are designed, and the reasoning is based on the Semantic Web Rule Language(SWRL). The ontology model for the RHDL is designed and the prototype system of RHDL is implemented using protege and Jess tools.

BiOI nanobelts were synthesised by a one-pot solvothermal process in the presence of [Bmim]I. As-synthesised BiOI nanobelts showed higher photocatalytic activity in the aqueous RhB photodegradation system than BiOI nanosheets under visible-light irradiation. It could be widely used for the environmental purification of organic pollutants in an aqueous solution.

Lost circulation is a common problem in drilling project, especially the severe loss which consumes much material and costs much time, sometimes induced wellbore collapse, drill pipe sticking, overflow, blowout and well abandon at last. Based on theory of structure liquid, supramolecular chemistry, water-solubility salt-resisting and temperature-resisting polymer, we designed and synthesized the gel, called special gel, which is used to control severe lost circulation. When dispersed in water, a reversible supramolecular structure (dynamic physical cross-linking network) developed, which rendered the dispersion some special characteristics. This paper investigates the rheology of the gel which is accordance with pseudoplastic fluid with yield point. The gel has thixotropy, good tackifying effect and shear-thinning behavior, and visible viscoelasticity. Those rheology characteristics show the gel has the potential to plug the weak zone. The gel is hard to be dilute by formation fluids for its apparent viscosity and strong cohesive force. Its shear-thinning property can provide the gel be pumped and flow in pipes easily, and flow with high viscosity and resistance in the zone porous. And its visoelasticity make the gel has high flood efficiency to cut off the connection between the formation fluid and the drilling fluid in borehole. It will impose a higher pressure to push the gel system after the gel stay. And the gel has good Compatibility with common use lost circulation materials such as walnut shell, cement. When the loss pressure difference is too high, the gel can be used with bridge plug or cement. The gel is benefit to control severe lost circulation accompanying with water zones or overflow and loss coexist. The gel was successful to deal with severe loss in Sichuan, Changqin and Tuha oil fields in China.

Novel BiOCl–g-C3N4 composite photocatalysts were synthesized by a one-step chemical bath method. The composites were characterized using X-ray diffraction (XRD), high-resolution transmission microscopy (HRTEM), UV-visible light diffusion reflectance spectrometry (DRS), Fourier-transform infrared spectroscopy (FT-IR), and photoluminescence spectroscopy (PL). The results indicated that BiOCl was dispersed on g-C3N4 to form heterojunction structures with high specific surface areas. BiOCl–g-C3N4 showed higher photocatalytic activity than pure g-C3N4 and BiOCl for rhodamine B (RhB) degradation. The enhanced performance was induced by the high separation efficiency of photoinduced carriers. The active species trapping and quantification experiments indicated that the photoinduced charges transfer via a direct Z-scheme.

Ag/AgX (X=Cl, Br) indoor daylight-driven (DLD) photocatalysts were synthesised by a one-step chemical bath method at low temperature and characterised by X-ray diffraction patterns, X-ray photoelectron spectroscopy, field emission scanning electron microscope and UV-visible diffuse reflectance spectra. The Ag/AgX composites showed very high DLD photocatalytic activity for rhodamine B degradation. The photocatalytic mechanism over the Ag/AgX was analysed by active species trapping experiments. It showed that the photocatalytic degradation of organic pollutants in the Ag/AgX system proceeds mainly through direct holes transfer. This study has revealed that plasmonic indoor DLD photocatalysis may open a new frontier for indoor pollutant control around the clock under fluorescent lamp illumination.