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It is crucial to develop effective electrocatalysts with multiple active sites for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in order to promote the advance energy conversion and development of sustainable energy technology. Here, we synthesized hierarchical nanostructured Ni 2 P on carbon cloth using ionic liquid (IL) assisted sacrificial template strategy through a simple two-step hydrothermal phosphatization process, which served as an electrode for enhancing bifunctional water electrolysis. By changing the content of ionic liquids in the solvent, the morphology of Ni(OH) 2 precursors could be regulated, thereby altering the morphology of Ni 2 P. Ni 2 P exhibited remarkable electrocatalytic activity towards HER in acidic electrolytes with an overpotential of 132 mV at a current density of 10 mA cm−2, as well as OER in alkaline media with the overpotential of 309 mV. The excellent electrocatalytic activity of the Ni 2 P-2 could be attributed to its hierarchical nanostructure providing abundant active sites, which benefits from the structural end-capping effect of ILs. [Display omitted] • Directionally rearranged hierarchical nanostructured Ni 2 P was synthesized using a ionic liquid-assisted strategy. • The morphology of hierarchical nanostructured Ni 2 P is controlled. • Hierarchical nanostructured Ni 2 P possesses multiple active sites. • Hierarchical nanostructured Ni 2 P exhibits excellent HER and OER activities. [ABSTRACT FROM AUTHOR]

Homojunction structure could present synergetic effect of an enhanced charge transfer and decreasing the electron-hole recombination. In this investigation, rutile/anatase TiO 2 homojunction was prepared by sol-gel synthesis with nitric acid (HNO 3) as peptizing agent. Au/TiO 2 was prepared by photoreduction deposition process. The photocatalytic performance for water splitting and the degradation of methylene blue (MB) was evaluated. 1% Au/TiO 2 -HNO 3 possessed good photocatalytic activity with hydrogen evolution rate of 8.77 mmol/h/g, and MB degradation efficiency of about 69.70% under visible light irradiation. The results indicated TiO 2 -HNO 3 conceived optimum composition ratio of rutile and anatase phases to construct the homojunction structure enhancing charge transfer and decreasing the electron-hole recombination favorable for photocatalytic performance. Further, the strong metal-support interaction as well as the localized surface plasmon resonance (LSPR) of Au species accounted for the results of Au/TiO 2 especially Au/TiO 2 -HNO 3 possessing higher hydrogen evolution and degradation of MB performance than TiO 2. [Display omitted] • Rutile/anatase TiO 2 homojunction was prepared by facile sol-gel method. • Rutile/anatase TiO 2 homojunction achieved effective long-range charge separation. • Band gap narrowing can be achieved using homojunction. • Homojunction effect and metal-support interaction well improve photocatalytic performance. [ABSTRACT FROM AUTHOR]

• Ag single atoms (SAs) dispersed g-C 3 N 4 catalyst was prepared by a one-step photocatalytic immobilization strategy. • Rhodamine B as electron acceptor contributed to immobilize the Ag SAs and construct electron migration channels, endowing Ag SAs with more intrinsic activity. • The embedded Ag SAs provided electron transfer channels to achieve effective long-range charge separation and low bandgap. • Based on the synergistic effect between RhB and Ag SA/g-C 3 N 4 , Ag SA/g-C 3 N 4 exhibited enhanced photocatalytic performance for the degradation of organic pollutants in wastewater. Owing to their unique electronic structure, single atom (SA) catalysts exhibit high activity and selectivity in the photocatalytic elimination of organic compounds. Herein, to improve the intrinsic activity of Ag SAs, Ag SA/g-C 3 N 4 was synthesized via a one-step photocatalytic immobilization strategy. Ag SA/g-C 3 N 4 exhibited excellent photocatalytic performance in removing organic pollutants, achieving degradation efficiencies of 93.49% and 64.29% for rhodamine B (RhB) and tetracycline (TC), respectively, under visible-light irradiation for 180 min. This enhanced photocatalytic activity stemmed from the synergistic electronic interaction between Ag SA/g-C 3 N 4 and RhB, whose photocatalytic degradation contributed to immobilize the Ag SAs and construct electron migration channels. This electronic structure suppressed the aggregation of Ag SAs. Ag nanoparticles could retain a small particle size of 2.79 nm after being recycled thrice. This study provides an innovative method for the immobilization of Ag SAs to improve their photocatalytic activity in the removal of RhB and TC. [Display omitted] Ag SA/g-C 3 N 4 was prepared by one-step photocatalytic immobilization process with rhodamine B (RhB) as electron acceptor to help immobilize Ag SAs building interface electronic interaction, which endowed Ag SAs with more intrinsic activity. The novel electronic interaction between Ag SAs and g-C 3 N 4 facilitated strong light absorption. Ag SA/g-C 3 N 4 showed good photocatalytic activity for visible light degradation of RhB and tetracycline. [ABSTRACT FROM AUTHOR]

Hexagonal LnPO 4 (Ln = La, Ce) nanorods and monoclinic LnPO 4 (Ln = La, Ce) nanospheroids (NSPs) were synthesized by hydrothermal methods Au/LnPO 4 catalysts were prepared by a modified deposition-precipitation method. The samples were characterized by N 2 adsorption-desorption, ICP, XRD, TEM, EDX, XPS, and CO 2 -TPD. The catalytic tests for CO oxidation demonstrated that morphologies of LnPO 4 would influence the activity of Au/LnPO 4 . 1.0% Au/LaPO 4 -NRs catalyst exhibited best catalytic activity achieving complete CO conversion at 25 °C among Au/LnPO 4 catalysts. The sintering resistance of gold nanoparticles in Au/LnPO 4 upon calcination was enhanced due to the strong metal-support interaction. Au/LnPO 4 also showed good stability for CO oxidation with no deactivation after continuous operation for 10 h. The possible mechanism of CO oxidation on Au/LnPO 4 catalysts was also briefly described. [ABSTRACT FROM AUTHOR]

Abstract: In the financial market, well-performing stocks usually have some specific features in financial figures. This paper introduces a machine learning method of support vector machine to construct a stock selection model, which can do the nonlinear classification of stocks. However, the accuracy of SVM classification is very sensitive to the quality of training set. To avoid the direct use of complicated and highly dimensional financial ratios, we bring the principal component analysis (PCA) into SVM model to extract the low-dimensional and efficient feature information, which improves the training accuracy and efficiency as well as preserve the features of initial data. As empirical results show, based on support vector machine, within PCA after norm- standardization, the stock selection model achieves the entire accuracy of 75.4464% in training set and of 61.7925% in test set. Further, the PCA-SVM stock selection model contributes the annual earnings of stock portfolio to outperforming those of A- share index of Shanghai Stock Exchange, significantly. [Copyright &y& Elsevier]

• Janus-SiO 2 nanofluid is prepared by a novel chemical etching method. • Pure Janus-SiO 2 nanofluid presents a IFT of about 0.09 mN/m with kerosene. • Interfacial behaviours of three surfactants are improved by Janus-SiO 2. • The Janus-SiO 2 /surfactant nanofluid shows promising potential for enhanced oil recovery. • Janus-SiO 2 nanofluid has been industrialized due to its low-cost and simple preparation procedure. Janus nanoparticles with amphiphilic surfaces could be of particular significance for enhanced oil recovery (EOR) of reservoirs. However, currently available methods for preparing Janus nanoparticles are often complicated. Here we present a highly efficient and easily scalable one-step chemical etching method with NaOH as the etching agent for fabricating amphiphilic Janus-SiO 2 nanoparticles. The structure, interfacial behavior and improved oil recovery (IOR) potential of the as-prepared Janus-SiO 2 nanoparticles were systematically studied. Results show that Janus-SiO 2 nanoparticles with size less than 10 nm exhibit good dispersibility in water and amphiphilicity as well. When combined with various surfactants, they can significantly improve the oil recovery upon simulated water flooding, due to their good abilities to increase the sweep efficiency of surfactants and reduce the interfacial tension of oil–water emulsion. Oil recoveries are improved by 7.4–9.8% with addition of Janus-SiO 2 in surfactants compared to pure surfactant solutions, showing promising potential for EOR. [ABSTRACT FROM AUTHOR]

• 3D silica is prepared by a novel growth-aggregation-modification-growth strategy. • The 3D silica is suitable for separating surfactant stabilized oil-in-water emulsion. • The separation process without flux limitation is rapidly that completely within10 min. • 3D silica have been industrialized due to its low-cost and simple preparation procedure. The existing oil-water separation materials are often limited by their cost, efficiency and environmental implications, so they are difficult to achieve effective utilization in industry. Although silica nanoparticles have excellent environmental-friendly and rich raw materials, their use has been restricted due to poor porous structure or complex preparation process. Herein, we adopt a growth-aggregation-modification-growth strategy to prepare superhydrophobic silica with three-dimensional (3D) structure. Findings show that the as-prepared silica has a 3D network structure of a size of 11 µm, a pore volume of 2.79 cm3/g and an absorption capacity of 2.98 mL/g towards castor oil. Particularly, superhydrophobic silica exhibits an outstanding organic molecule separation performance from series of surfactant stabilized oil-in-water emulsions with size less than 10 µm and dyes in water. In addition, the 3D silica can act as a functional additive in polydimethylsiloxane (PDMS) for enhancing its hydrophobicity. The substrates coated with PDMS/silica composite present outstanding oil/water separation and self-cleaning performance which is due to the silica particles have excellent superhydrophobicity and porous 3D network. In terms of the well available low-cost raw materials and simple preparation method, the superhydrophobic 3D silica could find promising applications in the treatment of oily wastewater or preparation of self-cleaning surfaces. [ABSTRACT FROM AUTHOR]

To study the effect of O on β-Ti alloys with various β phase stability, Ti– x Nb–0.4O (x = 30, 32, 34, 36, 38, 40, 42, mass%) alloys were prepared by arc melting followed by homogenization, hot rolling, and solution treatment. To ensure the O content of the alloys, melting and hot rolling were performed under an Ar atmosphere, and homogenization and solution treatment were performed under vacuum conditions. The mass fractions of O in the Ti–Nb–O alloys were finally accurately controlled in the range of 0.4–0.5%. The phase composition of the alloys was determined by analyzing the X-ray diffraction patterns, the microstructure was observed by optical microscopy, and the mechanical properties were measured by tensile tests. The ω phase and α" phase were found in the solution-treated Ti–30Nb–0.4O. Ti–30Nb–0.4O showed the lowest yield strength owing to the existence of the α" phase. O suppressed ω phase and α" phase transformations during quenching, and showed an obvious solution-strengthening effect. Because the O content of the alloys was essentially the same, the Ti– x Nb–0.4O alloys showed similar tensile strengths. The Young's moduli of the alloys ranged from 60 to 69 GPa, and the elongations were all higher than 15%. Particularly, Ti–36Nb–0.4O exhibited desirable mechanical properties, including a Young's modulus of 61 GPa, a tensile strength of 760 MPa, and an elongation of approximately 35%. • The O content was accurately controlled in the range of 0.4–0.5% using high vacuum equipment. • O effectively suppressed the formations of the α" phase and ω phase during quenching. • Ti-36Nb 0.4O alloy exhibited desirable high strength and low Young's modulus. [ABSTRACT FROM AUTHOR]

Asia-Pacific ground-based Optical Space object Observation System (APOSOS) is an international cooperation project, which is initiated and supported by Asia-Pacific Space Cooperation Organization (APSCO). Currently, APOSOS consists of three Observation Nodes in Pakistan, Peru and Iran, and a Data and Operation Management Center in National Astronomical Observatories, Chinese Academy of Sciences. Each Observation Node is equipped with a dedicated 15 cm aperture refracting telescope, which is capable of real-time astrometric data reduction. APOSOS aims to develop a tracking network of space object to acquire accurate astrometric measurements of space objects owned by APSCO member states. In this paper, we present an overview of APOSOS's design and development. The APOSOS's detecting capability of tracking a space object is darker than 12 m in LEO or 16 m in GEO, the size of which is equivalent to a diameter of 10-cm class in LEO or meter class in GEO respectively. A parametric estimation model is setup to profile APOSOS's capability in different tracking missions, which is verified by experimental observations. Preliminary results of tracking observations of SLR satellites showed that RMS of APOSOS astrometric measurements in RA/DEC is better than 5 ″ . [ABSTRACT FROM AUTHOR]

The immune effect of 2′-fucosyllactose (2′FL) in mice fed an infant formula (IF) milk diet was studied. Forty-five BALB/C mice were randomly divided into 3 groups: control, and low and high dose of 2′FL. 2′FL was administered once daily for 30 days and all the mice were fed IF milk diet. On day 30, the spleen and thymus were isolated and weighed for immune organ index calculation. Natural killer (NK) cell activity, T-lymphocyte proliferation capacity and delayed-type hypersensitivity reactivity (DTH) were measured. There was a significant increase in thymus index in high dose 2′FL group (p < 0.05). T-lymphocytes in high dose 2′FL group also tended to proliferate more compared with the control group (p < 0.05). NK cell activity and the degree of DTH were improved in both 2′FL groups (p < 0.05). These data demonstrated that 2′FL can improve immunity in mice fed an IF milk diet. [ABSTRACT FROM AUTHOR]