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[Display omitted] • Hydrophobicity of [Bmim] 2 [CuCl 4 ] was reported. • Hygroscopic process of [Bmim] 2 [CuCl 4 ] was monitored in situ by time-dependent IR. • Hydrogen bond in [Bmim] 2 [CuCl 4 ] was analyzed by IR bands position shift. • Water molecules aggregation states in [Bmim] 2 [CuCl 4 ] was discussed. By dissolving copper chloride in [Bmim]Cl (1-butyl-3-methylimidazolium chloride), chloride ions can coordinate with copper ions and form [CuCl 4 ]2−, thereby inducing the solution being hydrophobic. In the present work, hydrogen bonds between [Bmim]+ and anions are analyzed and discussed by two-dimensional correlation spectroscopy. Time-dependent attenuated total reflection spectroscopy (ATR-FTIR) is introduced to monitor the hygroscopic process of [Bmim] 2 [CuCl 4 ] and [Bmim]Cl in situ. Hygroscopic capacity and rate of [Bmim] 2 [CuCl 4 ] shrink compared with [Bmim]Cl. The change of water molecular clusters has been studied by second-derivative spectra in the hygroscopic process. The behaviors of water molecular in the two ionic liquids are also distinctive. [ABSTRACT FROM AUTHOR]

Novel hollow molecularly imprinted polymer (HMIPs) microspheres were synthesized via two-stage dispersion polymerization and swelling seed polymerization technique with nicotinamide (NAM) as the template molecule. Binding experiments showed that the HMIPs possessed excellent binding properties toward N-nitroamines, including fast mass transfer rate, and efficient adsorption performance with the adsorption capacity reaching up to 1.7 mg/g, which was 3 times higher than that of hollow non-imprinted polymers (HNIPs). The fast binding kinetics for one N-nitrosamine (4-(methylnitrosamino)-1-(3-pyridine)-1-butanone, NNK) was attributed to the hollow porous structure with the imprinted cavities on both external and internal surface of the HMIPs. [ABSTRACT FROM AUTHOR]

Abstract: Graphene hybridized with ZnO could produce an efficient photocatalyst. The ZnO nanoparticles were firstly coated with an appropriate amount of graphene oxide, the graphene oxide was then in situ reduced to form the ZnO/graphene composite. Graphene hybridized ZnO photocatalyst showed enhanced photocatalytic activity for the degradation of organic dye. The degree of photocatalytic activity enhancement strongly depended on the coverage of graphene on the surface of ZnO nanoparticles. The sample of 2wt% graphene hybridized ZnO showed the highest photocatalytic activity, which was about 4 times as that of pristine ZnO. The enhancement of photocatalytic activity was attributed to the high migration efficiency of photo-induced electrons and the inhibited charge carriers recombination due to the electronic interaction between ZnO and graphene. The electronic interaction was systematically studied and confirmed by the photoelectrochemical measurements. [ABSTRACT FROM AUTHOR]

Abstract: Highly crystalline orthorhombic Bi2MoO6 particles with high visible-light photocatalytic activity have been controllably synthesized via a facile hydrothermal process without adding any surfactant. The morphologies of Bi2MoO6 with nanosheet and microrod can be selectively obtained by adjusting the pH value of the reactant. The formation mechanisms of nanosheet and microrod structures were then discussed based on the H+ cations adsorption abilities on different crystal faces. The Bi2MoO6 samples prepared at acidic condition showed 12 times higher photocatalytic activity than that prepared at basic condition under visible-light irradiation. The reason for the big difference in the photocatalytic activities for the Bi2MoO6 samples obtained at different pH values were systematically studied based on their shape, size and the variation of local structure. [Copyright &y& Elsevier]

Abstract: La0.5Ba0.5MnO3 nanocubes and nanoparticles were synthesized by hydrothermal and co-precipitation methods, respectively. The catalytic performances and thermal stabilities of the samples in the oxidation of CO and CH4 were evaluated. La0.5Ba0.5MnO3 nanocubes showed much higher catalytic activity and thermal stability in CO and CH4 oxidation compared with the nanoparticles. After running at 560°C for 50h under the reaction conditions in CH4 oxidation, the surface area of the nanoparticles decreased significantly, while the nanocubes well maintained their surface area. Jahn–Teller effect had a significant influence on the catalytic performances of La0.5Ba0.5MnO3 nanocubes and nanoparticles. The much higher catalytic activity and thermal stability of La0.5Ba0.5MnO3 nanocubes were mainly predominated by the perfect single crystal structure. [Copyright &y& Elsevier]

Abstract: Bismuth molybdate films with various phase structures including α-Bi2Mo3O12, β-Bi2Mo2O9, γ-Bi2MoO6, and γ′-Bi2MoO6 are fabricated on the indium–tin oxide glass substrates from an amorphous heteronuclear complex via the dip-coating method by appropriate adjustment of the reaction conditions. α-Bi2Mo3O12, β-Bi2Mo2O9, and γ-Bi2MoO6 film can be obtained at 400 °C, 500 °C, and 500 °C for 1 h, respectively. At 500 °C, γ′-Bi2MoO6 can be obtained for 4 h. Film formation process is proposed based on the experimental results. Thin γ-Bi2MoO6 films exhibit high photoresponse under visible light irradiation. Incident photon to current conversion efficiency of thin γ-Bi2MoO6 film starts to increase near 450 nm. And, it can reach 4.1% at 400 nm. The top of the valence band and bottom of the conduction band are roughly estimated to be −0.71 and 1.69 eV, respectively. In contrast, γ′-Bi2MoO6 generated weak photocurrent; α-Bi2Mo3O12 and β-Bi2Mo2O9 film has no photoresponse under visible light irradiation. The reason for the difference in the visible light response was discussed. [Copyright &y& Elsevier]

Abstract: In this work, the Ni(OH)2 core–shell nanostructures were fabricated by a hydrothermal method without using any templates. After the core–shell sample was annealed, the novel hollow NiO nanostructures were obtained. The Ostwald ripening process was proposed to elucidate the formation of the samples. Moreover, Ag/NiO flowers were prepared by impregnating hollow NiO particles with Ag(NO3)3 solution. The samples were characterized by TEM, HREM, SAED, XRD, BET, SEM and EDS methods. Most importantly, Ag/NiO flowers and hollow NiO nanostructures exhibited the excellent catalytic activities for CO oxidation. [Copyright &y& Elsevier]

Abstract: The novel hollow Mn3O4-in-Co3O4 and hollow Co3O4 microspheres were prepared through a hydrothermal route, following by subsequent impregnation and annealing. The samples were characterized by SEM (EDS), TEM (ED), XRD, and N2 adsorption. The chemiluminescence (CL) and catalytic properties for CO oxidation over these hollow samples were evaluated. The hollow Mn3O4-in-Co3O4 catalyst showed a stronger CL response to CO and a higher catalytic activity for CO oxidation, compared with the hollow Co3O4 sample, which was attributed to the novel structure of crystals-in-ball. [Copyright &y& Elsevier]

Abstract: To efficiently utilize the solar light and improve the photooxidation technique for wastewater purification, a new type of photoelectrode, visible light responsive Bi2WO6 nanoflake film, was covered onto the indium–tin oxide glass substrate via the electrostatic self-assembly deposition. The photocatalytic oxidation, electro-oxidation, and photoelectrocatalytic (PEC) oxidation of 4-chlorophenol (4-CP) in aqueous solution using the film electrode were investigated and compared under visible light irradiation (λ >400nm). The experimental results demonstrated that 4-CP could be degraded by the nanoflake film under visible light irradiation or by applying a bias potential greater than 0.8V. Based on X-ray photoelectron spectra (XPS) analysis of the electrode after electrochemical reaction, the electropolymerization was suggested to occur in the electro-oxidation process. Furthermore, degradation efficiency of 4-CP was largely increased by combined electro-oxidation and photocatalysis. And, it is the largest at the bias potential of 2.0V. The characteristics of the PEC degradation of 4-CP were also investigated by electrochemical impedance spectroscopy (EIS). It is shown from the EIS that the PEC degradation appears to be a simple reaction on the electrode surface, suggesting that only one step of charge transfer is involved in the electrode process. The total organic carbon analysis indicated that 4-CP could be efficiently mineralized during the PEC process. [Copyright &y& Elsevier]

In order to enhance Ni-EDTA decomplexation and Ni recovery via photoelectrocatalytic (PEC) process, TiO 2 /Ni-Sb-SnO 2 bifunctional electrode was fabricated as the photoanode and activated carbon fiber (ACF) was introduced as the cathode. At a cell voltage of 3.5 V and initial solution pH of 6.3, the TiO 2 /Ni-Sb-SnO 2 bifunctional photoanode exhibited a synergetic effect on the decomplexation of Ni-EDTA with the pseudo-first-order rate constant of 0.01068 min−1 with 180 min by using stainless steel (SS) cathode, which was 1.5 and 2.4 times higher than that of TiO 2 photoanode and Ni-Sb-SnO 2 anode, respectively. Moreover, both the efficiencies of Ni-EDTA decomplexation and Ni recovery were improved to 98% from 86% and 73% from 41% after replacing SS cathode with ACF cathode, respectively. Influencing factors on Ni-EDTA decomplexation and Ni recovery were investigated and the efficiencies were favored at acidic condition, higher cell voltage and lower initial Ni-EDTA concentration. Ni-EDTA was mainly decomposed via ·OH radicals which generated via the interaction of O 3 , H 2 O 2 , and UV irradiation in the contrasted PEC system. Then, the liberated Ni2+ ions which liberated from Ni-EDTA decomplexation were eventually reduced to metallic Ni on the ACF cathode surface. Finally, the stability of the constructed PEC system on Ni-EDTA decomplexation and Ni recovery was exhibited. [Display omitted] [ABSTRACT FROM AUTHOR]

Schematic plot of the attacking process of ROS and ACS to E.coli. [Display omitted] • ACS outperformed ROS on the inactivation of E.coli. • O 2 – conceived higher inactivation rate of E.coli than OH. • The membrane was broken firstly, and then inactivated by disinfectant. • Total protein would be the attacking point for ROS rather than RCS. Comprehensive study on the roles of reactive oxygen species (ROS) and active chlorine species (ACS) on the failure of bacteria cell were crucial for the development of electrochemical oxidation disinfection. Pure Na 2 SO 4 and chloride-containing solution were used to generate ROS and ACS, separately. When 14.4 mA/cm2 current density was applied, 5 logs reduction of E.coli was achieved with 60 min treatment in pure Na 2 SO 4 solution, while in the chloride-containing solution, E.coli was completely inactivated in 15 min as the initial concentration was about 7.5 logs. Cell membrane damage is a crucial step in electrochemical oxidation disinfection process. With 3.6 mA/cm2, there were ∼ 1.1 logs cells injured and it was about 37 times to that of inactivated cells with 5 min treatment in pure Na 2 SO 4 solution. Hydroxyl radical and superoxide radical were confirmed responsible for the inactivation of E.coli in pure Na 2 SO 4 electrolyte, while hypochlorite was dominated in chloride-containing solution. Noticeable shrinkages, wrinkles, and indentations were observed on the cell surfaces after treatment without any differences for ROS and ACS. However, total protein would be the attacking point for ROS rather than ACS. The changes of Optical density, total organic carbon, and potassium ions leakage presented slight differences. Nucleic acid matters may be destroyed in the electrochemical disinfection process, while the damage on nucleic acid fragment need more research to reveal. [ABSTRACT FROM AUTHOR]

• A portable NIRS quantification of 6-gingerol in ginger powder was developed. • Real ginger powder from different geographical origins were modeled and recognized. • NIRS analysis of ginger can be considered not just in lab but also at casual inspection. Ginger powder is an important spice that is susceptible to improper sales such as adulteration or geographical fraud. In this study, a portable near infrared spectroscopy was used to quantitatively predict the 6-gingerol content, an important quality index of ginger, as well as to identify the gingers from three origins in China. Specifically, the optimal preprocessing method was first investigated by comparing the predictions of models. Then three feature variable selection methods including PCA, CARS, and RFrog, on the quantitative analysis of 6-gingerol were also compared, respectively. After comparison, the PLS model established on the S-G combined with SNV preprocessing outperformed the others. The PLS regression of 6-gingerol with variables selected by RFrog possessed the R c 2 of 0.9463, R p 2 of 0.9497, and the RPD of 4.2257, respectively. Moreover, the results further verified that the LDA model by SPA variables extraction successfully identify gingers from different origins with 100 % accuracy. [ABSTRACT FROM AUTHOR]

Abstract: An efficient TiO2 photocatalyst was obtained by surface hybridization with a thin layer of C60 molecules. The photocatalytic performance of C60-hybridized TiO2 under ultraviolet light irradiation was enhanced by 4 times compared with that of P25-TiO2 photocatalyst. The enhanced photocatalytic activity for C60-hybridized TiO2 was originated from the high migration efficiency of photo-induced electrons on the interface of C60 and TiO2, which was produced by the interaction TiO2 and C60 with a conjugative π-system. The interaction was confirmed by the Raman spectroscopy, infrared spectroscopy and photoelectrochemical measurements. The enhancement of photocatalytic activity strongly depended on the coverage of C60 molecules on the surface of TiO2, and the optimum hybridization effect was found at a weight ratio of 2.5wt% (C60/TiO2). The mechanism for the enhanced photocatalytic activity of TiO2 by C60 was discussed. [ABSTRACT FROM AUTHOR]

The carbon nanotubes (CNTs) have been combined with graphitic carbon nitride (g-C 3 N 4 ) through the amidation reaction. The hybrid catalyst of g-C 3 N 4 -CNTs with well-defined and stable structure exhibits efficient catalytic performance (32.6 μmol h −1 ) for photocatalytic H 2 O 2 production in the presence of formic acid under visible light. The value of electron transfer during the oxygen reduction reaction (ORR) process obtained from the Koutecky-Levich plot for g-C 3 N 4 -CNTs (n = 1.96) is higher than that for g-C 3 N 4 (n = 1.29), suggesting that the CNTs covalent combined with g-C 3 N 4 can promote the electrons generation. The p -benzoquinone (PBQ) scavenger experiments, the electron spin resonance (ESR) signal and quantitative experiment of O 2 − results reveal that the negative shifts of the conduction band (CB) level from g-C 3 N 4 to g-C 3 N 4 -CNTs can enhance the single-electron reduction of O 2 to O 2 − and further promote the sequential two-step single-electron O 2 reduction reaction to H 2 O 2 . [ABSTRACT FROM AUTHOR]

Tobacco-specific N -nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine. • The plasma levels of TSNAs in smokers and non-smokers were measured. • The variations of plasma TSNAs of smokers after switching were investigated. • The reductions in smoke TSNA yields can reduce mean biomarkers of exposure levels. • TSNAs and nicotine metabolite biomarkers in plasma were highly correlated. • The plasma TSNA were valid and reliable biomarkers of human exposure to TSNAs. [ABSTRACT FROM AUTHOR]

Tobacco-specific N -nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine. • The plasma levels of TSNAs in smokers and non-smokers were measured. • The variations of plasma TSNAs of smokers after switching were investigated. • The reductions in smoke TSNA yields can reduce mean biomarkers of exposure levels. • TSNAs and nicotine metabolite biomarkers in plasma were highly correlated. • The plasma TSNA were valid and reliable biomarkers of human exposure to TSNAs. [ABSTRACT FROM AUTHOR]

CuO/TiO2 composites were prepared by the impregnation method, in which TiO2 nanosheets and nanorods are used as the precursors, respectively. We investigated the effect of the TiO2 surface structure on the activity and recyclability of the photocatalysts. The hydrogen production activities were tested in a 3 mol L−1 methanol aqueous solution under UV-light irradiation. After deposition of Pt, both Pt@CuO/TiO2 samples displayed higher hydrogen production activities than the Pt/TiO2 samples. The results reveal that the TiO2 sheet-based samples display higher hydrogen production activities and stability than the TiO2 rod-based ones. It is proposed that a more stable p-n heterojunction form at the interface between CuO and TiO2 nanosheets owing to the strong interaction of CuO with the {0 0 1} facets of the TiO2 sheets, which significantly refrains the recombination rate of electrons and holes. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the LiFePO4 nanorods are synthesized in an ionic liquid (IL) in the presence of a surfactant. The samples are characterized by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, electron diffraction and nitrogen adsorption. The as-obtained LiFePO4 nanorods in the IL have the diameter of about 200nm and the length of 1–2μm; but the aggregated LiFePO4 microparticles are obtained in the aqueous solution. The results show that a higher temperature and a longer duration are needed in the IL than in the aqueous solution for the formation of LiFePO4; that both IL and the surfactant play the key roles in the formation of LiFePO4 nanorods. Furthermore, their charge and discharge properties are investigated. The LiFePO4 nanorods show a higher discharge capacity (150 at 1C rate) and a higher rate capability than the aggregated particles (133mAhg−1). The adopted IL approach may provide a “green” route to achieve excellent battery materials. [Copyright &y& Elsevier]

Abstract: The highly porous Co3O4 nanorods are prepared by a simple hydrothermal method, in which CO(NH2)2 is employed as precipitating agent, and K60 (PVP, polyvinylpyrrolidone) is used as surfactant to improve the stability of the nanoparticles. For comparison, the bulk Co3O4 is prepared by thermal decomposition of cobalt nitrate. The samples are characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (ED), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N2 adsorption, Thermogravimetric analysis (TG), H2-temperature programmed reduction (TPR), CO-, CH4-, and O2-temperature programmed desorption (TPD). The catalluminescence (CTL) and catalytic properties of the samples are investigated extensively. The results show that the Co3O4 nanorods are composed of nanoparticles, and have a large number of pores with a narrow pore size distribution (1.5–7nm). Compared with the bulk Co3O4, the porous nanorods have a higher CTL intensity of CO oxidation, and a higher activity of CH4 combustion especially at a higher gas hourly space velocity (GHSV), which has been ascribed to its porous structure and larger surface area. [Copyright &y& Elsevier]

Abstract: The flower-like CuO nanostructures were hydrothermally synthesized without using any template. The influences of hydrothermal temperature and time on the growth of nanostructures were investigated. The samples were characterized by means of scanning electron microscope (SEM), X-ray powder diffraction (XRD), transmission electron microscope (TEM), high-resolution transmission electron microscope (HRTEM), selected area electron diffraction (ED), and N2 adsorption isotherm. Interestingly, these architectures are made of three-order structures. The formation mechanism of the flower-like CuO was proposed and explained. Furthermore, the chemiluminescence (CL) and catalysis properties of the flower-like CuO were also investigated. The flower-like nanostructures showed the high-CL intensities and reactive activities for CO oxidation. The flower-like CuO can be used to fabricate a highly sensitive CL detector. This CL mode is a rapid and effective method for the selection of new catalysts from thousands of materials. [Copyright &y& Elsevier]

Abstract: The hollow Co3O4 microspheres (HCMs) were prepared by the carbonaceous templates, which did not need the surface pretreatment. The chemiluminescence (CL) and catalytic properties for CO oxidation over these hollow samples were evaluated. The samples were characterized by scanning electron microscopy (SEM), energy disperse spectra (EDS), transmission electron microscopy (TEM), selected area electron diffraction (ED), X-ray diffraction (XRD), temperature-programmed desorption (TPD) and N2 adsorption. The influences of filter’ band length, flow rate of gas, test temperature, and particle structure on CL intensities were mainly investigated. It was found that compared with the solid Co3O4 particles (SCPs), HCMs had a stronger CL intensity, which was ascribed to its hollow structure; and that CL properties of the catalysts were well correlated with their reaction activities. Moreover, HCMs were used to fabricate a highly sensitive gas detector, which is a rapid and effective method for the selection of catalysts or the detection of environmental deleterious gases. [Copyright &y& Elsevier]