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The photocatalytic properties of Zn/Co zeolite imidazolate frameworks (ZIF-ZnCo) prepared by various Zn/Co ratio are of significantly diversity due to the morphology structure of the ZIF-ZnCo. Thereinto, the prepared ZIF-ZnCO-8:1 is excellent capability by virtue of its 3D cross-shaped structure. Spectral test results show that as-prepared novel 3D cross-shaped ZIF-ZnCo has a lower recombination rate of electron and hole pairs than the lamellar and dodecahedral, thus improving the photocatalytic ability. The photocatalytic ability of 3D cross-shaped ZIF-ZnCo was carefully investigated for removing mixed solution of Congo Red (CR) and Cr(VI). The photocatalytic reduction ability of 3D cross-shaped ZIF-ZnCo was 22% higher than ZIF-8 for Cr(VI). Meanwhile, CR was altogether removed at dark processing and Cr(VI) was removed 70% after dark processing 120 min and photocatalytic 240 min. Therefore, the high adsorption and photocatalytic capacity denote the potential application of 3D cross-shaped ZIF-ZnCo.

Reasonable design and preparation of non-noble metal electrocatalysts with predominant catalytic activity and long-term stability for oxygen evolution reaction (OER) are essential for electrocatalytic water splitting. Ni foam (NF) is highlighted for its 3D porous structure, impressive conductivity and large specific surface area. Herein, nano/micro structured dendritic cobalt activated nickel sulfide grown on 3D porous NF (Co–Ni3S2/NF) has been successfully synthesized by one-step hydrothermal method. Due to the ingenious incorporation of Co, Co–Ni3S2/NF electrode shows auspicious electrocatalytic performance for OER compared with Ni3S2/NF electrode. As a result, Co–Ni3S2/NF needs overpotential of only 274 and 459 mV at current density of 10 and 50 mA cm−2, respectively, while Ni3S2/NF requires overpotential of 344 and 511 mV. At potential of 2.0 V (vs. RHE), Co–Ni3S2/NF displays current density of 191 mA cm−2, while Ni3S2/NF just attains current density of only 135 mA cm−2. Moreover, Co–Ni3S2/NF demonstrates excellent stability for uninterrupted OER in alkaline electrolyte. The strategy of designing and preparing cobalt activated nickel sulfide grown on NF renders a magnificent prospect for the development of metal-sulfide-based oxygen evolution catalysts with excellent electrocatalytic performances.

Shore-side container cranes (SCC) are widely used in ship loading and unloading. However, the SCC is often damaged by the seismic wave shock. In seismic response analysis, the setting of damping coefficients has a large impact on the accuracy of the calculation results. In order to better design the SCC mechanical performance, the improved damping coefficient calculation method is proposed. The results of the simulation and the experiment are compared under the different seismic conditions. The results show that the influence of the damping coefficient calculation method on the SCC seismic response increases with strengthened seismic intensity. When the peak acceleration is small, the simulation results under different damping coefficients are almost the same and are close to the experiment values. When the peak acceleration is large, only the error between the simulation results obtained by the improved method and the experimental values is less than 5%. It is thus concluded that the improved damping coefficient calculation method is accurate and reliable.

The efficient separation of low-concentration radionuclides by the eco-friendly adsorbent is a compelling requirement in the development of nuclear industry. Hence, a novel composite consisted of one-dimensional palygorskite (Pal) and three-dimensional pomelo peel (PP) is prepared by self-assembly approach (PP/Pal) and coupling agent approach (PP/KPal) for removing uranium (U(VI)) from aqueous solution. Moreover, the mass ratio (PP/Pal), adsorbent dosage, pH, contact time, temperature, and ionic strength are investigated. Two adsorption kinetic models and isotherm models are used to investigate the kinetic behaviors and adsorption capacity, respectively. The maximum adsorption capacities were 370.5 mg·g-1 on PP/Pal and 357.3 mg·g-1 on PP/KPal at pH 6.0, contact time 150 min and 25 °C. Meanwhile, the composite can be easily separated from water via a simple filtering. Furthermore, thermodynamic parameters indicate that adsorption is an endothermic and spontaneous process. And the surface complexation, ion exchange, and electrostatic attraction play a vital role. This work shows that the PP/Pal composite with high efficiency, low cost, and green has a further application in the treatment of wastewater containing U(VI).

Special TiO2 arrays with exposed facets were prepared in different solvents by low- temperature solvothermal synthesis. The morphology, phase and photocatalytic performance influenced by the various solvent polarities were characterized using field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectra and electrochemical testing. The results show that differences of solvent polarity are the main force driving differences in array growth; therefore, anatase TiO2 arrays with different crystal facets can be synthesized by tuning solvent polarity. TiO2 arrays prepared in cyclohexane are the best at oxidizing methyl orange through photocatalysis, followed by arrays prepared in toluene and ethanol. Arrays prepared in toluene are the best at reducing Cr(VI) photocatalytically, followed by those prepared in cyclohexane and ethanol. These differences in photocatalytic power are due to the ratio among the different crystal facets that are exposed, which affects the migration behavior of the photogenerated electrons and holes. In addition, the probable growth mechanisms of self-assembled ordered TiO2 arrays in different solvents are described.

s Nanosized particles of Bi0.95Y0.05Fe0.97M0.03O3 (M ​= ​Mn,Co,Ni,Cu,Zn) were successfully synthesized through thermal decomposition coordination precursors with diethylenetriaminepentaacetic acid (H5dtpa) as ligand. All prepared samples were characterized by XRD, Uv–vis DRS, SEM, PL, EIS, VSM and so on. From XRD results, the main phase of the samples was rhombohedral R3c (161) BiFeO3, and contained a small amount of soft iron ore Bi25FeO40. The phase and morphology of prepared samples were affected by doping ions. The average grain size of the samples was about 20 ​nm.T.The Uv–vis demonstrated the band gap of all samples was less than 2 ​eV and the response to light of all samples extended from ultraviolet region to visible region (~650 ​nm).The BFO–Y–Mn exhibited the minimum band gap of 1.77 ​eV. At the same time, photocatalytic activities of all samples prepared were evaluated through the photocatalytic degradation of methyl orange (MO). BiFeO3 co-doping with 5%Y3+ and 3%Mn2+ exhibited excellent photocatalytic activity for MO solution. In the present of BFO–Y–Mn, the degradation rate of MO under light irradiation of 3 ​h was about 98%.

A flaky photocatalytic composite of anatase@natural rutile(A@NR) was obtained using one-step microwave hydrothermal synthesis, which was designed to overcome the low photocatalytic efficiency stemming from high electron-hole recombination and a narrow photoresponse range. The characterizations were completely elucidated using X-ray diffraction, field emission scanning electron microscopy, Brunauer Emmett Teller surface area, ultraviolet–visible diffuse reflectance spectroscopy, and photoluminescence spectra. The efficiency of A@NR in photocatalytic degradation of methyl orange was determined to be close to that of P25 under UV light and superior to that of P25 under visible light. The excellent photocatalytic activity results from the synergistic effects of substituting Fe ions, which alter the band structure, and the isomerism of anatase and natural rutile, which separates the photogenerated electron holes. The calculated apparent quantum efficiencies of 32.8 and 12.9% for A@NR, under UV and visible light irradiation, respectively, show a higher catalytic activity and a more effective photoinduced electron-hole separation in A@NR than in P25.

The treatment process of metal plating wastewater in industry usually exists excessive consumption of chemicals, coproduction of sludge and complex reuse of metal. At present, some available technologies have been designed for effective removal of specific metal ions rather than entire metals ions in effluents. Herein, a novel strategy of treating waste with waste is proposed that using metal plating wastewater containing Zn(Ⅱ) to prepare 3D Luffa cylindrical (LC) / heterogeneous ZIFs (h-ZIF-8) composite (LC/h-ZIF-8) for photocatalytic degradation of organic pollutants (Nitrofurazone (NFZ), Methylene blue (MB), Rhodamine B (RhB) and Congo red (CR)) and mixed-dye wastewater. The strategy realized the efficient treatment of electroplating wastewater, expediently reuse of metal ions and removal of organic contaminants. Moreover, investigations of cycling performance indicated the photocatalytic stability and easy separation from water. Furthermore, the spectroscopy and electrochemical are employed to elaborate possible degradation mechanisms, expounding the LC/h-ZIF-8 possess lower recombination rates of carriers and transfer resistance of electron compared with ZIF-8. Therefore, the work proposes a new strategy for the efficient treatment of metal wastewater and achieves the combination of resource recovery and wastewater treatment with the advantages of simple operation and mild conditions.

Herein, a phosphomolybdic acid (PMo12) and graphene oxide (GO) based new electrochemical sensor (PMo12/GO/GCE) was developed for determination of diphenylamine (DPA). Spherical PMo12 was uniformly anchored on GO matrix by cost-efficient and facile electrodeposition approach. Cyclic voltammetry and differential pulse voltammetry were utilized to investigate electrochemical behavior of DPA on PMo12/GO/GCE. As expected, the sensor showed remarkable electrocatalytic activity toward DPA. The linear amperometric response of DPA at 0.55 V (vs. SCE) was obtained in a wide concentration range of 0.05 ~ 400 µM with a detection limit of 6.0 nM (S/N = 3). In addition, PMo12/GO/GCE displayed favorable reproducibility, selectivity and durable stability. The feasibility of constructed sensor was verified by detecting DPA in real apple juice samples with a satisfactory test results, showing its application prospects in detecting DPA in fruit samples.

Y3+ doped Bi2O3 photocatalysts with enhanced photocatalytic activity were synthesized via thermal decomposition of molecular precursor at 500 °C and characterized by X-ray powder diffraction (XRD), Brunauer–Emmett–Teller surface area, field emission scanning electron microscopy (FE-SEM), energy dispersive analysis of X-rays (EDX), ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), and photoluminescence spectra (PL). The XRD results indicated that the introduction of Y3+ ions can stabilize the phase of Bi2O3. The DRS results indicated that the doping of Y3+ increased the visible light absorption ability of Bi2O3 and red-shifts appeared when compared with pure Bi2O3. Their photocatalytic activities were evaluated through the photocatalytic degradation of methyl orange. The results showed that an appropriate concentration of yttrium dopant can enhance the photocatalytic performance of Bi2O3 due to the strong visible light absorption and the efficient inhibition of the recombination of photogenerated electron–hole pairs. The active species trapping experiments indicated · O 2 − is the main active species in the photocatalytic reaction. Recycling experiments demonstrated that Y-doped Bi2O3 has strong photostability and recyclability and it will be a promising photocatalyst for the photodegradation of organic dyes in water.

A novel method for the preparation of molecularly imprinted nanospheres is presented by premix membrane emulsification technique. On the example of chloramphenicol (CAP), the imprinted nanospheres were prepared using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EDMA) as cross-linker. The synthesis conditions of the nanospheres were optimized. When the membrane pore size is 1.4 mu m, transmembrane pressure is 2.00 MPa, transmembrane numbers are 5 times and the volume ratios of oil-water in the coarse emulsions is 1:20, the resulted nanospheres are relatively uniform and their sizes are between 300-800 nm. Furthermore, the effect of the ratio of CAP-MAA on imprinting performance was investigated, and the selective adsorption experiment indicates that the imprinted nanospheres have good selectivity for CAP. Additionally, adsorption kinetics and adsorption isotherm of the imprinted nanospheres exhibit that the adsorption equilibrium time is around 60 min and the maximum theoretical static binding capacity is up to 158.78 mg g(-1). Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.

Samnium(III)-bismuth(III) heterobimetallic complexes, SmBi(edta)(NO3)2·7H2O (1) and SmBi(dtpa)(NO3)·3.5H2O(2) (edta=ethylenediaminetetraacetate, dtpa=diethylenetriaminepentaacetate), were synthesized and characterized by means of X-ray single crystal diffraction, X-ray powder diffraction, elemental analysis, ICP, FT-IR spectra and thermal analysis. The structure analysis revealed that 1 is in crystalline and 2 is in non-crystal state. Complex 1 crystallizes in monoclinic, space group P2(1)/n with a=1.2622(2) nm, b=0.81157(15) nm, c=2.3634(5) nm, β=105.340(2)°, V=2.3347(8) nm3, Z=4, Dc=2.563 g·cm−3, µ=10.125 mm−1. Bridging edta4− anions between Bi(III) atoms and Sm(III) atoms result into infinite 3D network structure. Thermal decomposition of the two complexes proceeds in similar stages, i.e., dehydration, pyrolysis of ligand, and decomposition of salt, and the final residue is oxide. In addition, the spectral properties have been studied through FL spectra and UV-Vis DRS. The two complexes exhibit one broad band Bi 6s6p-6s2 emission under UV excitation and the characteristic Sm3+ ion 4G5/26HJ/2 (J=5, 7, 9, 11) transitions under visible light excitation, respectively.

Bacillus subtilis was first used to remove Sr(II) from low-level radioactive wastewater. Influence parameters, biosorption kinetics and biosorption equilibrium were investigated. The results showed that the maximum adsorption capacity of Sr(II) at over 2,000 mg g−1 by Bacillus subtilis was higher than for other biosorbents. At pH 6.3, Sr(II) concentration of 15 mg L−1, biomass dosage of 0.3 g L−1 and temperature of 20 °C, the maximum removal efficiency was as high as 96.3% at 1,440 minutes. The biosorption kinetics and the equilibrium isotherm data can be described by the pseudo-second-order equation and Freundlich isotherm equation, respectively. The negative values of ΔG and the positive values of ΔH implied that Sr(II) biosorption on Bacillus subtilis was a spontaneous and endothermic process. Fourier transform infrared spectroscopy indicated that the functional groups, hydroxyl, carboxylate and amide groups, might participate in the interaction between Sr(II) and Bacillus subtilis.

Preparation of uniform size molecularly imprinted nanospheres for erythromycin with good selectivity and high binding capacity by precipitation polymerization were presented, in which erythromycin, methacrylic acid and ethylene glycol dimethacrylate are used as template molecule, functional monomer and cross-linker, respectively. The synthesis conditions of molecularly imprinted nanospheres were optimized and the optimal molar ratio of erythromycin to functional monomer is 1:3. The molecularly imprinted polymers were characterized by scanning electron microscope, laser particle size analyzer and BET, respectively. The results suggested that molecularly imprinted nanospheres for erythromycin exhibited spherical shape and good monodispersity. Selectivity analysis indicated that the imprinted nanospheres could specifically recognize erythromycin from its structure analogues. Furthermore, adsorption kinetics and adsorption isotherm of the imprinted nanospheres were employed to investigate the binding characteristics of the imprinted nanospheres. The results showed that the imprinted nanospheres have high adsorption capacity for erythromycin, and the maximum theoretical static binding capacity is up to 267.0188 mg g(-1).