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Activated two-dimension (2D) materials are used in various applications as high-performance catalysts. Breaking the long-range order of the basal plane of 2D materials can highly promote catalytic activity by supplying more active sites. Here we developed a method to synthesize ultrathin MCoOx (M = V, Mn, Fe, Ni, Cu, Zn) amorphous nanosheets (ANSs). These Co-based ANSs show high oxygen evolution reaction (OER) activity in alkaline solution due to the broken long-range order and the presence of abundant low bonded O on the basal plane. The stable Fe1Co1Ox ANSs also show an overpotential of ca. 240 mV of achieving 10 mA/cm2 in OER, better than most reported transition metal-based electrocatalysts. [ABSTRACT FROM AUTHOR]

The photoelectric conversion efficiency of organic materials is limited by the exciton splitting at the organic interface which is determined by the exciton binding energy (E b). However, E b is controversial and hard to directly measure by current methods. We propose a dispersion relation to establish a model to accurately extract E b from absorption spectrum. We synthesize an organic-inorganic hybrid perovskite crystal (CH 3 NH 3 PbI 3) and use the absorption spectrum to verify the method. The result of E b is 15 meV at room temperature, which is smaller than 26 meV (thermal energy), implying that our model is not affected by the hot carrier effects. Moreover, this model is applicable to various organic materials (18 kinds). Especially, the binding energy of perovskite is 5 meV under 2 K, which is the same as the result estimated experimentally under 50 Tesla condition. Furthermore, this model allows estimating the effective mass, dielectric constant and excition radius. This work will allow a better understanding of the optoelectronic properties at the interface of organic materials. [ABSTRACT FROM AUTHOR]

Highlights • This paper explains the reason for high ideality factor (>2, even 6). • Decreasing the energy disorder would improve the performance of solar cell. • The way in point 2 is very effective if n ID is big but useless if n ID gets near to 1. • This paper provides a semi-analytical model based on Fermi distribution. Abstract Organic semiconductor has recently emerged as a promising and versatile material for solar cells. This paper shows that the structural order of the electron transport layers has a significant influence on the ideality factor and the power conversion efficiency of organic solar cells. By using Fermi-Dirac distribution, we demonstrate that both ideality factor and degeneracy will up to 3, even 6, when the energy disorder of the transport layer is large enough. By comparing the numerical values of 15 materials with experimental data, our results show that the ideality factor is almost the same value as the degeneracy when the light intensity gets near to 1 mW/cm2. Additionally, both degeneracy and ideality factor have a positive correlation with the energy disorder. However, the power conversion efficiency will decrease as the energy disorder increasing. These results shed light on the real reason for high ideality factor and the origin of the power conversion efficiency loss, and provide a direction to increase the power conversion efficiency of the organic solar cells. [ABSTRACT FROM AUTHOR]

As a large province committed to developing ecological civilization, Jiangxi province is among the top provinces that boast the largest amount of traditional villages. Although maintaining a relatively intact ecological environment, Jiangxi Province is relatively backward in economy, which makes it an urgent mission for the local authorities to vigorously develop traditional village tourism. But many traditional villages landscapes have been destroyed in the process of development since there is no specific guidelines or regulations. This paper analyzed the development of Youshan Village--a traditional village that has made remarkable achievements in developing its tourism resources while conserving its original landscape features, concluded the methods and principles of constructing traditional village landscapes of Jiangxi province and expected to further explore the development mode for prospering tourism in the traditional villages. [ABSTRACT FROM AUTHOR]

A feasibility of using 110 resin as an adsorbent for Nd(III) was examined with various chemical methods. Batch studies were carried out to determine the influence of operational conditions, such as initial pH of solution, temperature, contact time, and initial concentrations. The optimal conditions in terms of initial pH and equilibrium time was 6.0 (HAc–NaAc system) and 72 h, respectively. The maximum adsorption capacity was estimated to 308 mg/g at 298 K calculating from the Langmuir isotherm. Nd(III) ions could be well eluted by using 3.0 mol/L HCl solution and the absorbent could be regenerated and reused. Thermodynamic and kinetics parameters were studied, from which the adsorption process was spontaneous and the adsorption was endothermic in nature. The Thomas model based on the experimental column study data was used to predict the breakthrough curves and to determine the characteristics parameters of the column useful for process design. Moreover, the adsorption mechanism was proposed by the IR spectroscopic technique. [ABSTRACT FROM AUTHOR]

A novel chelating resin, polyacrylonitrile-2-amino-1,3,4-thiadiazole (PAN-ATD), was prepared via one-step reaction and its structure was characterized by elemental analysis and FT-IR. The adsorption properties of the resin for Hg(II) were investigated by batch and column experiments. Batch adsorption results showed that PAN-ATD had high affinity towards Hg(II) and the maximum adsorption capacity estimated from the Langmuir model was 526.9 mg/g at 308 K. The adsorption kinetic and equilibrium data were well fitted to the pseudo-second-order model and the Langmuir isotherm model, respectively. Furthermore, the resin can be easily regenerated and reused with less than 10% loss of adsorption capacity. Also, the resin and its metal complexes were studied by SEM, TGA, and energy dispersive X-ray spectroscopy (EDS). With good overall properties (a high selectivity adsorption capacity, easy to be regenerated and stable application capacity) PAN-ATD resin can not only be used in selective removal of Hg(II) from waste solution, but also be used for preparation of the separation and enrichment column applied in the analysis and detection area. [ABSTRACT FROM AUTHOR]

Highlights: [•] The chelating cross-linked chitosan (CBM-chitosan) is a novel adsorption material. [•] 2-(Chloromethyl) benzimidazole was first connected to cross-linked chitosan. [•] CBM-chitosan shows high selectivity and good adsorption capacity toward Hg2+. [•] CBM-chitosan can be eluted effectively and has satisfactory reusability. [•] CBM-chitosan is a potential biosorbent for Hg2+ analysis, removal and recovery. [ABSTRACT FROM AUTHOR]

A novel chelating resin, polyacrylonitrile-2-aminothiazole(PAN-AT), was synthesized simply by the reaction of polyacrylonitrilewith 2-aminothiazole. Optimization of the PAN-AT synthesis was carriedout at different temperatures, different molar ratios of reagents,and different time intervals in N,N-dimethylformamide (DMF) using response surface methodology (RSM)for the first attempt. The functional group capacity (the contentof the functional group) and the percentage conversion of the functionalgroup of PAN-AT prepared under the optimum conditions were 3.94 mmol/gand 41.10%, respectively. The structure of PAN-AT was characterizedby elemental analysis and FTIR. Meanwhile, the adsorption propertiesof the resin for Hg(II) were investigated by batch and column experiments.The results suggested that the resin possessed much better adsorptioncapability for Hg(II) than for other metal ions and the maximum saturatedadsorption capacity estimated from the Langmuir model was 454.9 mg/gat 308 K. Furthermore, the resin could be regenerated through thedesorption of the Hg(II) anions using 3.0 mol/L HNO3solutionand could be reused to adsorb again. Finally, the resin and its metalcomplexes were studied by SEM, TGA, and energy dispersive X-ray spectroscopy(EDS). Also, the PAN-AT chelating resin could provide a potentialapplication for a treatment process of Hg(II) contaminated wastewater. [ABSTRACT FROM AUTHOR]

Abstract: A novel ethylenediamine functionalized chelating resin (ED resin) with simple technology, high adsorption capacity and significant selectivity was synthesized. It was characterized by elemental analysis and infrared spectra, and was applied for determination of metal ion in tea samples. The optimized synthesis conditions is molar ratio ED:Cl=2:1, 100°C as reaction temperature and DMF as solvent. ED resin can be used in separating Cu(II) from aqueous solutions. The adsorption processes were evaluated by Langmuir and Freundlich isotherms. Pseudo-second-order kinetics showed better accordance. Thermodynamic parameters indicated that adsorption process was spontaneous and endothermic. Thomas model was applied to determine the characteristic parameters of column useful for process design. Finally, Cu(II) can be eluted by 1.0molL−1 HCl solution. AAS method was applied for copper determination after the pre-concentration step, and the results indicated that ED resin is essentially free from interferences, which can contribute to accurate determination in waters and foods. [Copyright &y& Elsevier]

37 gasoline blending components and hydrocarbons composition of refined oil are analyzed by GC/ MS, including nalkane, isoparaffin, naphthenic hydrocarbon, aromatic hydrocarbon, isoolefine, normal olefin, cyclic olefins, diolefin. The author adopts correlational analysis method to investigate the relativity between hydrocarbon substance and gasoline property; adopts stepwise linear regression method to establish a regression model of property and hydrocarbons composition; and determine the main hydrocarbon substance which exerts influence on the property according to the regression model: aromatic hydrocarbon influences the octane number, 10% vaporization temperature, 50% vaporization temperature, density and chroma most; olefin, especially the isoolefine and normal olefin, influence 0% vaporization temperature, acidity, colloid, induction period, iodine value and saturated steam pressure most. F-test result shows that the regression model is obvious and it an provide reference for predicting the quality of gasoline. [ABSTRACT FROM AUTHOR]

Indium and its compounds have numerous industrial applications in the manufacture of liquid crystal displays and semiconductors. They are considered hazardous substances. This article reports the research into the recovery of In(III) from aqueous solution by sorption. Cation-exchange carboxylic resin (D155 resin) was used as a sorbent for indium(III) ions extraction in this research. The factors of parameters, such as pH, kinetics, temperature and sorption isotherm, and column experiment were investigated. In batch system, D155 resin exhibited the highest In(III) ion uptake as 279 mg/g at 298 K with a pH value 5.00. The sorption data matched the Langmuir isotherms very well. The thermodynamic parameter ΔG was negative, and this result indicated that the sorption of In(III) ions on D155 resin was spontaneous. Furthermore, the positive value of ΔH showed that the sorption was endothermic in nature. In(III) ions can be eluted with 0.5 mol/L HCl solution. The Thomas model was applied to experimental column data to determine the characteristic parameters of the column which is useful for process design. [ABSTRACT FROM AUTHOR]

Abstract: Polystyrene-triethylenetetramine resin (PS-TETA) was synthesized from chloromethylated polystyrene (PS-Cl) and triethylenetetramine (TETA) and employed as a new adsorbent for heavy metal removal from aqueous solutions. The effects of reaction parameters (reaction solvent, molar ratio of reagents, reaction temperature and reaction time) on the functional group capacity of PS-TETA resin were monitored to specify the best synthesis conditions. The functional group capacity and conversion percentage of functional group of PS-TETA prepared under the optimum condition were 2.13mmol FG/g and 49.79%, respectively. The structure of PS-TETA was confirmed by elemental analysis and infrared spectra. The optimization of experimental conditions and parameters including pH, contact time, initial metal ion concentration for the removal of heavy metals were investigated. The maximum adsorption capacities of the resin for Hg(II), Cd(II) and Pb(II) evaluated from the Langmuir model were 344.8, 212.8 and 147.1mg/g, respectively. Desorption studies revealed that Hg(II), Cd(II) and Pb(II) can be easily removed from PS-TETA by altering the pH values of the solution using HCl, which indicate that PS-TETA is a promising adsorbent for heavy metals removal from aqueous medium. [Copyright &y& Elsevier]

Abstract: In this work, a weakly acidic ion exchange fiber (PTFE-g-AA) has been prepared by 60Co irradiation grafting with acrylic acid (AA) onto the polytetrafluoroethylene (PTFE) fiber. The grafted fiber was characterized by FTIR, SEM and TGA technique. The exchange capacity of the PTFE-g-AA fiber is 3.87mmol/g. The adsorbent material was employed for Er(III) uptaking by batch and column experiments. Kinetics studies showed that the adsorption process obeyed pseudo-second-order kinetics. The adsorption isotherms followed both the Freundlich model and Langmuir model. The maximum adsorption capacity of the PTFE-g-AA fiber for Er(III) was evaluated to be 142.0mg/g for the Langmuir model. It was found that 0.75M HCl–0.25M NaCl solution provided effectiveness of the desorption of Er(III) from the PTFE-g-AA fiber. Various thermodynamic parameters such as standard enthalpy (ΔH 0), standard entropy (ΔS 0) and standard free energy (ΔG 0) were evaluated. The adsorption of Er(III) on the PTFE-g-AA fiber was found to be endothermic in nature. The Thomas model was successfully applied to experimental data to predict the breakthrough curves and to determine the characteristics parameters of the column useful for process design. [Copyright &y& Elsevier]

Abstract: The adsorption and desorption behaviors of Cd(II) on gel-type weak acid resin (GTWAR) have been investigated. The influence of operational conditions such as contact time, initial concentration of Cd(II), initial pH of solution and temperature on the adsorption of Cd(II) has also been examined. The results show that the optimal adsorption condition of GTWAR for Cd(II) is achieved at pH=5.95 in HAc–NaAc medium. The maximum uptake capacity of Cd(II) is 282 mg/g GTWAR at 298 K. The adsorption of Cd(II) follows the Langmuir isotherm and Freundlich isotherm, and the correlation coefficients have been evaluated. Even kinetics on the adsorption of Cd(II) has been studied. The apparent activation energy E a and adsorption rate constant k 298 values are 2.95 kJ/mol and 3.02×10− 5 s−1, respectively. The calculation data of thermodynamic parameters which ΔS value of 110 J/(mol K) and ΔH value of 13.1 kJ/mol indicate the endothermic nature of the adsorption process. Whilst, a decrease of Gibb''s free energy (ΔG) with increasing temperature indicates the spontaneous nature of the adsorption process. Finally, Cd(II) can be eluted by using 0.5 mol/L HCl solution and the gel-type weak acid resin can be regenerated and reused. The sample was described by IR spectroscopy and scanning electron micrographs (SEM). [Copyright &y& Elsevier]

Abstract: The adsorption properties of 4-amino-1,2,4-triazole resin (4-ATR) for Re(VII) were investigated by static and dynamic adsorption–desorption measurements with ultraviolet–visible spectroscopy. The influence of conditions such as temperature, initial solution pH and contact time on the adsorption curve was studied. It was found that the 4-amino-1,2,4-triazole resin was suitable for adsorption of Re(VII). The saturated adsorption capacity was 354 mg·g−1resin at pH 2.6 in HAc–NaAc medium at 298 K. The adsorption rate constant was k 298 =8.2×10−5 s−1. The adsorption behavior of 4-ATR for Re(VII) obeyed the Freundlich empirical equation; whilst changes in adsorption with temperature gave an enthalpy change ΔH = − 11.8 kJ·mol−1. The molar ratio of the functional group of 4-ATR to Re(VII) was about 2:1. Re(VII) adsorbed on 4-ATR was eluted by 1.0~5.0 mol·L−1 HCl with 100% quantitative elution in 4.0 mol·L−1 HCl solution. The resin can be regenerated and reused without apparent decrease in adsorption capacity. [Copyright &y& Elsevier]

Abstract: The sorption behaviour and mechanism of a novel chelate resin, imino-diacetic acid resin (IDAAR), for Yb(III) has been investigated in HAc–NaAc medium. The sorption of Yb(III) obeys the Freundlich isotherm. Optimum sorption for Yb(III) on IDAAR is at pH 5.13 and the statically saturated sorption capacity is 187 mg/g resin at 298 K. Yb(III) can be eluted using 1~2 mol L−1 HCl and the resin can be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant is k 298 =1.57×10−5 s−1; the apparent activation energy is 13.8 kJ mol−1 and the enthalpy change ΔH of IDAAR for Yb(III) is 29.8 kJ mol−1. The sorption mechanism of IDAAR for Yb(III) was examined by using chemical methods and IR spectrometry. The molar coordination ratio of the functional group of IDAAR to Yb(III) is 3:1 with the coordination compound formed between oxygen atoms in the functional group of IDAAR and Yb(III). [Copyright &y& Elsevier]

Light ideality factor, the slope of open-circuit voltage versus the logarithm of the illumination intensity, is a topic of continuing debate in solar cells. However, the generally accepted interpretation of the ideality factor will fail when the factor is larger than 2. This work demonstrates that the mechanism for light ideality factor is degeneracy of carriers by using the generalized Einstein coefficient in the drift-diffusion model. Moreover, this work proposes that the light ideality factor should satisfy the relation of 0:1:2:4 under different illumination conditions. This work challenges the generally accepted interpretation of the ideality factor and provides a better understanding of organic solar cells. Image 1 • The reason for high light ideality factor is the degeneracy of carriers. • The ideality factor has a relation of 4:2:1:0 under different illumination. • SRH recombination is dominate under low P in condition. • This paper proposes an analytical model to explain the ideality factor. [ABSTRACT FROM AUTHOR]

The performance of organic solar cells is limited by the exciton. However, the theoretical model to study the nature of the exciton is separated into exciton diffusion and dissociation. This article proposes a unified model by combining both exciton diffusion and dissociation. This model can be reduced to the classical model of exciton diffusion or dissociation. Moreover, this model quantitatively explains meaningful experimental data of the short‐circuit current characteristic at different active layer thicknesses that cannot be fitted by the two classical models. In sum, this model is useful for researching the mechanism of the exciton in thin organic materials, which make some significant contributions to blend, multilayer, and A–D–A small‐molecule acceptor solar cells. [ABSTRACT FROM AUTHOR]

A series of transition-metal (M = Mn, Fe, Co, Ni, Cu) ion-exchanged tungstophosphoric acid (H 3 PW 12 O 40 ; TPA)-based ionic liquid (IL) catalysts, synthesized by incorporating metal and methylimidazolium propyl sulfobetaine (MIMPS) zwitterionic IL precursors onto TPA, were exploited for acetalization of benzaldehyde (BzH) with ethylene glycol (EG). These organic-inorganic, water-soluble M-MIMPS-TPA composite salts possess not only strong Brønsted and Lewis acidities but also exhibited unique self-separation property desirable for catalyst separation and recycling. The superior acetalization activities observed for these novel M-MIMPS-TPA catalysts are attributed to their strong acidity, Brønsted/Lewis acid synergy, and low mass transport resistance. Among them, the Ni[MIMPSH]PW 12 O 40 catalyst showed extraordinary catalytic performance and durability with a benzaldehyde glycol acetal selectivity and yield of 99.0 and 94.6%, respectively, in excellent agreement with results from response surface methodology. Further kinetic study gave rise to an activation energy of 34.11 kJ/mol for the acetalization reaction, surpassing most reported catalysts. [ABSTRACT FROM AUTHOR]

Using macroporous ion exchange resin macrosphere D113 as an inexpensive organic carbon source, a composite precursor was constructed with Bi(OH)3 using a hydrothermal method. A series of new bismuth-based composite photocatalytic materials, Bi2O3/C, were prepared using pyrolysis technology and it was shown that the bismuth element existed in the form of Bi2O3 in the composite. It was uniformly distributed on the surface of a graphitized carbon macrosphere and exhibited a high electron transfer rate. The UV-vis diffuse reflectance spectrum and photoluminescence verified that Bi2O3/C exhibited a good light absorption performance and a low photogenerated electron hole recombination rate due to the optimized band structure. Electrochemical tests such as an i–t curve and electrochemical impedance spectroscopy showed that Bi2O3/C-500 had a good photoelectric response. In combination with the Tauc curve, the band structure of Bi2O3/C-500 was verified. Bi2O3/C-500 could degrade methylene blue (20 mg L−1) completely in 120 min, and the degradation rate remained at 90.30% for three photocatalytic cycles. The preparation method of the new Bi2O3/C was simple, inexpensive, and convenient for the commercial application of dye wastewater. [ABSTRACT FROM AUTHOR]

37 gasoline blending components and hydrocarbons composition of refined oil are analyzed by GC/ MS, including nalkane, isoparaffin, naphthenic hydrocarbon, aromatic hydrocarbon, isoolefine, normal olefin, cyclic olefins, diolefin. The author adopts correlational analysis method to investigate the relativity between hydrocarbon substance and gasoline property; adopts stepwise linear regression method to establish a regression model of property and hydrocarbons composition; and determine the main hydrocarbon substance which exerts influence on the property according to the regression model: aromatic hydrocarbon influences the octane number, 10% vaporization temperature, 50% vaporization temperature, density and chroma most; olefin, especially the isoolefine and normal olefin, influence 0% vaporization temperature, acidity, colloid, induction period, iodine value and saturated steam pressure most. F-test result shows that the regression model is obvious and it an provide reference for predicting the quality of gasoline. [ABSTRACT FROM AUTHOR]

A series of novel resin-based MOF composites Co-MOF@D113-N (N = 1, 6) were prepared using 2-methylimidazole, cobalt acetate and D113 resin, through the layer-by-layer self-assembly method. The Co-MOF presented an amorphous form with the inducement of resin groups and the loading capacity increased with the number of self-assembled layers. The strong anchoring effect between Co and N effectively improved the thermal stability of the composites. The adsorption experiments showed that the adsorption capacity of the Co-MOF@D113-6 resin for Cu(II) increased with temperature in the range of 283–303 K. The adsorption capacity of Co-MOF@D113-6 for Cu(II) increased under the synergistic effect of MOFs and D113. The maximum adsorption capacity of Co-MOF@D113-6 was 273.88 mg g−1. The fitting results showed that the adsorption of Cu(II) by the Co-MOF@D113-6 conformed to the pseudo-second-order kinetic model dominated by chemisorption, and also conformed to the preferential Freundlich adsorption isotherm model. A low cost resin carrier combined with a high efficiency MOF composite adsorption material provided high efficiency and low consumption for promising development. [ABSTRACT FROM AUTHOR]

Given the necessity and urgency in removing organic pollutants such as malachite green (MG) from the environment, it is vital to screen high-capacity adsorbents using artificial neural network (ANN) methods quickly and accurately. In this study, a series of ZIF-67 were synthesized, which adsorption properties for organic pollutants, especially MG, were systematically evaluated and determined as 241.720 mg g−1 (25 ℃, 2 h). The adsorption process was more consistent with pseudo-second-order kinetics and Langmuir adsorption isotherm, which correlation coefficients were 0.995 and 0.997, respectively. The chemisorption mechanism was considered to be π-π stacking interaction between imidazole and aromatic ring. Then, a Python-based neural network model using the Limited-memory BFGS algorithm was constructed by collecting the crucial structural parameters of ZIF-67 and the experimental data of batch adsorption. The model, optimized extensively, outperformed similar Matlab-based ANN with a coefficient of determination of 0.9882 and mean square error of 0.0009 in predicting ZIF-67 adsorption of MG. Furthermore, the model demonstrated a good generalization ability in the predictive training of other organic pollutants. In brief, ANN was successfully separated from the Matlab platform, providing a robust framework for high-precision prediction of organic pollutants and guiding the synthesis of adsorbents. [Display omitted] • Adsorption mechanism of ZIF-76 on dyes mainly depends on π-π stacking interaction. • Python-based ANN accurately predicts ZIF-67 adsorption of malachite green. • The model consists of 12 neuron, L-BFGS algorithm, and Tanh activation function. • Systematically explores the interplay of preparation, structure, and adsorption. • Python-based ANN outperforms Matlab in predictive accuracy and generalization. [ABSTRACT FROM AUTHOR]

Nanofluids is a new type of efficient cooling mass. In the present experimental work, a new SiO 2 -ethylene-glycol/deionized water nanofluids with excellent static storage and dynamic stability was prepared. The static storage and high temperature dynamic stability of the nanofluids was investigated experimentally (particle size measurements, TEM photographs, Zeta Potential experiments). The corrosion resistance of nanofluids was investigated by means of aluminium pump cavitation experiments. The effects of concentration, temperature and Reynolds number on the thermophysical properties and heat transfer efficiency of nanofluids were studied. Based on the thermophysical parameters (thermal conductivity and viscosity) of nanofluids at different temperatures, the experimental correlations were fitted. The results show that the stability period of the nanofluids is more than 36 months. The convective heat transfer coefficient can be increased by more than 36.1% with the addition of 6 wt% nanofluids at 25 °C. The nanofluids provides improved heat transfer and good corrosion protection and impact resistance. [ABSTRACT FROM AUTHOR]

Abstract: A mesostructured tungsten disulfide (WS2) material was prepared through a solid-phase reaction utilizing ammonium tetrathiotungstate as the precursor and n-octadecylamine as the template. The as-synthesized WS2 material was characterized by X-ray powder Diffraction (XRD), Low-temperature N2 Adsorption (BET method), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The characterization results indicate that the WS2 material has the typical mesopore structure (3.7nm) with a high specific surface area (145.9m2/g), and large pore volume (0.18cm3/g). This approach is novel, green and convenient. The plausible mechanism for the formation of the mesostructured WS2 material is discussed herein. [Copyright &y& Elsevier]

The MCTS‐g‐AT was developed as a novel magnetic adsorbent with core‐shell structure. Its unique synthesis route endows MCTS‐g‐AT with green, convenient, economical and safe characteristics, and also good selective adsorption of Hg(II). The material was characterized using an appropriate set of spectroscopic and analytical techniques (SEM, EDS, XRD, VSM, FTIR, and TGA). Its adsorption kinetics fits the pseudo‐secondary model well and adsorption isotherm fits the Langmuir equation well, suggesting the mechanism of chemisorption with monolayer adsorption. The results of the thermodynamic parameters indicate spontaneous and endothermic process. Column adsorption experiments showed that the maximum adsorption capacity of Hg(II) was 207.6 mg/g (298 K). Moreover, the Hg(II) adsorbed on composite microspheres was completely eluted by 3 mol/L HNO3 or 4 mol/L HCl. Furthermore, MCTS‐g‐AT adsorption column combined with spectrophotometer can achieve more accurate detection of Hg(II) in aquatic products. [ABSTRACT FROM AUTHOR]

Sudan I, as a common pigment, is harmful to people's health. In this work, the alkaline peanut shell as the base, epichlorohydrin and DMF as the solvent, with HBP-NH2 as the ligand to compose terminal amino-branched peanut shell. Optimization of the modified peanut shell was carried out at different temperatures, different molar ratios of reagents, and different time intervals in HBP-NH2 using response surface methodology (RSM) for the first attempt. The structure of modified peanut shell was characterized by FT-IR and elemental analysis. The adsorption properties of the modified peanut shell for Sudan I were investigated by batch and column experiments. Batch adsorption results suggested that modified peanut shell had a high adsorption capability for Sudan I and its maximum saturated adsorption capacity was 248.14 mg/g at 308 K, estimated from the Langmuir model. The modified peanut shell and its metal complexes were studied by TGA and SEM. Furthermore, the modified peanut shell can be eluted easily using 2 mol/L NaOH. HBP-NH2-P not only has a potential application for the selective removal of Sudan I from waste solutions but also has an application in the analysis and detection areas. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • We report a green chemical method to synthesis the chelating fiber APF and the APF-PAR. • The APF has excellent selective adsorption with Hg2+ and Cu2+, with 435.1 mg/g and 141.7 mg/g just in 25–30 min. • The APF-PAR can recognize the Hg2+ just in 2 s, and it can be clearly recognized by naked eyes. • It is the first time to define the solid-base chromogenic sensor to detect heavy metal ions. Abstract To advocate environment friendly detection idea, we adopted the green chemical method to synthesis the 1-(2 amino ethyl) piperidine functionalized polyacrylonitrile fiber (APF) and the chromogenic fiber 4-(2-pyridylazo) resorcinol (APF-PAR). The APF has high adsorption selectivity of Hg2+ and Cu2+, and the change of structure, surface morphology and thermo-stability before and after adsorption have been characterized by the infrared spectra, scanning electron microscope and thermogravimetric analysis. The APF achieved the adsorption equilibrium of Hg2+ just in 25 min and the adsorption capacity is 435.1 mg/g, while the adsorption equilibrium of Cu2+ costs 30 min and the adsorption capacity is 141.7 mg/g. The chromogenic fiber APF-PAR can recognize the Hg2+ and Cu2+ in 2 s, which benefits from the rapid mass transfer and small fluid resistance of the chelating PAN fiber. The color changed from orange to purplish red due to the variation of HOMO-LOMO energy gaps during the reaction which confirmed by the UV–vis absorption spectrum. It also has high selectivity and excellent adsorption performance, which provides more convenient, accurate, reliable and faster testing methods of Hg2+ and Cu2+ in environmental medium. [ABSTRACT FROM AUTHOR]

Abstract: A highly Z‐selective phosphorylation by Manganese(III) acetylacetonate‐mediated cross‐dehydrogenative‐coupling of enamides and phosphine oxides has been developed under mild conditions. The reaction shows broad substrate scope and functional group compatibility. DFT studies revealed that the formation of Z‐products is presumably due to the presence of an intramolecular hydrogen bond. β‐Aminophosphine could be readily obtained by reduction and hydrolysis of the product. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the optimum preparation condition of casein- carrageenan conjugate by ultrasonic Maillard dry treatment. The stable microcapsule was self-assembly prepared by the conjugates applied to protect red pigment from paprika. The optimum substrate ratio of Cas-Ca is 1:2, the reaction time and temperature were 24 h and 60 °C. Finally, the optimal degree of grafting reached 78.05%. Conjugation with carrageenan could further enhance solubility and emulsifying properties of casein. Glycosylation self-assembly nanoparticles were prepared with ultrasonic treatment, and the stability of the nanoparticles were excellent. Cas-Ca was effectively used to encapsulate PRP, and the PRP and PRP-microcapsule were stored for six days under the condition of high temperature, lighting, and food additives to observe the PRP retention rate. These results indicated the outstanding protective effect of microcapsule on PRP. Cas-Ca could be used as an effective carrier of PRP. They could effectively control release behavior in simulated gastrointestinal fluid. Cas-Ca microcapsule was disintegrated and released slowly within 3 h in simulated gastric fluid, but released rapidly within 1 h in intestinal environments, and the total release rate reached 76.6%. [ABSTRACT FROM AUTHOR]

• Binding of protein to EGCG delayed the decline of antioxidant activity of EGCG. • EGCG enhance the cross-linking effect of particles in composite protein emulsion. • Glycosylated protein nanoparticles had good retention and protection to EGCG. • Release rate of EGCG in intestinal fluid was higher than that in gastric fluid. The application of Epigallocatechin-3-gallate (EGCG) in food industry was limited by its low stability in aqueous solutions and poor bioavailability in vivo. The novel EGCG glycosylated arachin nanoparticles (Ara-CMCS-EGCG) and EGCG glycosylated casein nanoparticles (Cas-CMCS-EGCG) were prepared to improve the stability and bioavailability of EGCG. The effect of different variables on the storage stability and the slow-release behavior of novel glycosylation complexes in nanoparticle background solution and artificial gastrointestinal fluid were investigated. The results showed that the DPPH scavenging activity of Ara-CMCS-EGCG and Cas-CMCS-EGCG were stable in temperature (25 ∼ 70 °C). EGCG could enhance the crosslinking effect of molecular particles in glycosylation complexes solution. The glycosylated protein nanoparticles were stable to acid-base and enzymolysis in simulated gastrointestinal fluid. The release rate of EGCG in simulated intestinal fluid was higher than that in simulated gastric fluid. The glycosylated protein carrier can not only release EGCG slowly, but also significantly improve the stability and bioavailability of EGCG in simulated gastrointestinal fluid. [ABSTRACT FROM AUTHOR]

We present a strategy for the modification of an ion-exchange resin (D113) as an inexpensive carbon source to obtain a macrospherical photocatalyst precursor that can be transformed into a stable all-solid-state Z-scheme heterojunction catalyst (denoted Bi 2 O 3 -Co 3 O 4 @C). X-ray diffractometry and Fourier transform infrared and Raman spectroscopy measurements confirmed the presence of highly graphitized carbon in the complex. Significantly, the cost of the as-prepared material was only 1/200 of that of commercial carbon nanotubes and 1/80 of that of graphene oxide. Aided by the organic carbon source, Bi 2 O 3 -Co 3 O 4 @C showed an enhanced light absorption, hindered electron–hole recombination, and an enhanced photocurrent response. Under simulated solar irradiation, Bi 2 O 3 -Co 3 O 4 @C (20 mg/L) showed degradation efficiencies of 100%, 47.52%, 94.28%, and 100% for methylene blue, rhodamine B, tetracycline, and Cr(VI), respectively, after 120 min. Herein, the highest turnover frequency (TOF) obtained under irradiation was 2.5 h−1 for Cr(VI). Further, the degradation efficiency for methylene blue trihydrate remained 91.46% after five cycles, indicating significantly higher stability than that of a catalyst prepared without graphitic carbon. The optimized band structure and photocatalytic mechanism of Bi 2 O 3 -Co 3 O 4 @C were determined based on ultraviolet-visible measurements and plane-wave density functional theory calculations in VASP. The findings of this study indicate the promise of the Bi 2 O 3 -Co 3 O 4 @C macrospheres for industrial applications based on their photocatalytic performance, high stability, low cost, and suitable particle size. [Display omitted] • Z-scheme heterojunction was constructed under the mediation of graphitized carbon. • Bi 2 O 3 -Co 3 O 4 @C optimized structure promoted light absorption and photocurrent response. • Bi 2 O 3 -Co 3 O 4 @C showed better photocatalytic performance than binary and pure samples. • Combined with DFT calculation, all-solid Z-scheme mechanism of reaction was proposed. [ABSTRACT FROM AUTHOR]

It is imperative to remove the toxic selenium compounds selenite and selenate from waste water before releasing to the environment. In this study, a functionalized regenerable cellulose, based on the chemical modification of cellulose grafted thiomalic acid (TMA-C), was prepared simply with an efficient methodology for removing and recovering selenium(IV) effectively. Optimization of the TMA-C synthesis was carried out at different temperatures, different molar ratios, and dosage of catalyst using response surface methodology. The surface functionalization effect was detected with FTIR, SEM, zeta potential, EDS and TGA technique. And under optimum adsorption conditions (pH = 4.5, T = 318 K), TMA-C can remove toxic selenium compounds more than 99.9%, and have high adsorption capacity for Se(IV), which is 101.2 mg/g. The adsorption isotherms data fitted the Langmuir model well, and pseudo-second-order kinetics showed better accordance. In addition, in the batch desorption experiments, the TMA-C could be regenerated completely with 3.0 mol/L HCl and 2% KClO 3 solutions. Finally regenerable cellulose microcolumn-UV-spectrophotometry was developed for effective and economic determination of trace Se(IV). [ABSTRACT FROM AUTHOR]

An organic polymeric resin was synthesized by anchoring p-aminobenzoic acid onto macroporous chloromethylated polystyrene beads, and was used for Zn(II) removal from aqueous solutions. The resin exhibited an initially rapid adsorption property for Zn(II) with equilibrium time of 10 h and the maximum adsorption capability approached 184.5 mg g−1. Optimum pH was 4.5. The mechanism of adsorption was investigated using kinetic, isotherm and thermodynamic models. The adsorption kinetic data were described well by a pseudo second-order model with R2 of 0.997. There was a negative Δ G (−17.98 kJ mol−1) and positive Δ H (13.58 kJ mol−1). HCl solution (1.0 mol l−1) could achieve an elution rate of 100%. The experimental data were well fitted by the Thomas model with R2 of 0.9826. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A series of Co 3 O 4 @C-N (N = 1, 2, 3) composite photocatalysts were prepared by simple agitation and pyrolysis for degradation of organic dyes. The hollow macroscopic spherical structure of Co 3 O 4 @C-2 was constructed by adjusting the pyrolysis time. Compared with pure Co 3 O 4 , the carbon composite Co 3 O 4 @C-2 significantly enhanced light absorption in the UV and visible range, improved the electron transport efficiency and prevented the necessary photoexcited electron-hole pair recombination. Hence, the photocatalytic degradation rate of methylene blue (MB, 20 mg/L) reached 100% in 120 min under UV–vis light irradiation. Under the coupling of Co 3 O 4 and graphitized carbon, Co 3 O 4 @C-2 obtained high structural stability, good reusability and low biotoxicity. Scavenging experiments and ESR test showed that •O2- radical was the active species for MB removal. After six cycles of tests, the photocatalytic efficiency of Co 3 O 4 @C-2 remained at 90.42%. The macroscopic spherical structure Co 3 O 4 @C-2 effectively avoids the problem of dispersion and recovery of powder catalyst, which also paves a path for the designing of candidate commercial photocatalyst with high efficiency and low consumption. [Display omitted] • Unique hollow structure was obtained by induction of amorphous Co-MOF. • Optimized band structure improved the photoelectric performance. • •O 2 - mainly determined the photocatalytic efficiency rather than •OH. • Co 3 O 4 @C-2 macrospheres obtained strong stability, low biotoxicity and good recycling. [ABSTRACT FROM AUTHOR]

Selenium (Se) is one of contaminants required to be regulated during water treatment. In this paper, we aim to prepare a novel functionalized cellulose, l -cysteine (L-Cys) modified surface of cellulose (L-CysC), with simple technology, and L-CysC can remove toxic selenium compounds entirely at pH values of 4.5. Meanwhile, L-CysC microcolumn-UV-spectrophotometry was developed for effective and economic determination of trace Se (IV). The BBD (Box-Behnken Design) of RSM (Response Surface Methodology) was applied to study the influences of reaction temperature, molar ratio and catalyst dosage. The surface functionalization effect was detected with FTIR, SEM, zeta potential, EDS, XPS and TGA techniques. Under optimum adsorption conditions (pH = 4.5, T = 318 K), The maximum removal capacity of L-CysC microcolumn toward Se (IV) was found to be 105.1 mg/g. The surface adsorption processes were evaluated by Langmuir isotherms and the kinetically proceeded according to Second-order kinetics model. Furthermore, L-CysC could be easily regenerated through the desorption of the Se (IV) anions using the mixture of 3.0 M HCl and 2% KClO 3 . [ABSTRACT FROM AUTHOR]

In this study, a unique carrier magnetic chitosan microspheres (MCTS) was simply synthesized by anchoring Fe3O4onto chitosan for direct immobilization of cellulases cross-linked by gluteraldehye. The structure and morphology were characterized using FT-IR, TGA, VSM and SEM. The optimum immobilization conditions were investigated: immobilized pH 7.0, amount of enzyme 15 mL (0.1 mg/mL), immobilization temperature 30 °C, immobilization time 5 h. At optimum conditions, MCTS achieved maximum enzyme solid loading rate of 73.5 mg/g, while recovery of enzyme activity approached to 71.6%. In the recycle test, immobilized cellulases operated without significant loss in its initial performances after 3 cycles, which indicated that immobilized cellulases can be regenerated and reused. The immobilized enzyme has better values of thermal and storage stability than that of free enzyme. Therefore, MCTS may be considered as a candidate with potential value of application in large-scale operations for cellulases immobilization. [ABSTRACT FROM PUBLISHER]

Edible mushrooms are widely usedtoday but the heavy metal pollution of edible mushrooms is not conducive to its industrialization. A novel chloromethylated polystyrene-g-2-adenine chelating resin (AR resin) with simple technology, high adsorption capacity, significant selectivity, and good regenerability was synthesized. Combined with the UV-Vis method, it was applied to mercury preconcentration and determination. The results indicated that the AR resin is essentially free from interferences, which can contribute to accurate determination in waters and foods. Optimization of the resin synthesis was carried out by using response surface methodology. The adsorption properties of the resin for Hg(II) were investigated by batch and column experiments. The statically and dynamic saturated adsorption capacities were 383.4 and 417.0 mg/g. The adsorption kinetic and equilibrium data were well fitted to the second-order model and the Langmuir isotherm model, respectively. Furthermore, the resin and its metal complexes were studied by Fourier transform infrared spectroscopy and thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

An efficient RhIII-catalyzed ortho-C-H bond activation for the synthesis of substituted isoquinolines and heterocycle-fused pyridines in aqueous medium has been developed. This method involves the in situ generation of ketimines from ketones and ammonium acetate and subsequent oxidative C-H bond activation/annulation of ketimines with alkynes to form the C-C/C-N bonds spontaneously. Various aryl ketones and internal alkynes were smoothly transformed into the desired heterocycles in moderate to excellent yields. The reaction exploits molecular oxygen as the sole oxidant by producing water as the only byproduct. Moreover, easily available NH4OAc was utilized as the nitrogen source, which makes this protocol practical and environmentally friendly. [ABSTRACT FROM AUTHOR]

• PANF-ATL fiber was prepared in one step using water as a solvent. • PANF-ATL fibers have selectively ability for Au(Ⅲ) at acidity 0.1 mol/L HCl. • PANF-ATL fibers exhibited good overall adsorption properties and could be easily eluted to Au(Ⅲ). • XPS analysis shows that the coordination reaction between N, S atoms and Au(Ⅲ). • PANF-ATL fibers showed good regeneration ability after 5 recycles. A novel environmentally-friendly polyacrylonitrile-2-amino-2-thiazoline chelating fiber (PANF-ATL) with good adsorption performance and thermal stability was synthesized in one step by nucleophilic addition reaction using water as a solvent. The optimum synthesis conditions for the chelating fibers are determined by controlling the synthesis temperature and the molar ratio of the reagents. The sulfur content and functional group capacity of the finally synthesized PANF-ATL were 3.82% and 1.19 mmol/g, respectively. PANF-ATL was characterized by elemental analysis, FTIR, TGA, SEM and XPS. Meanwhile, the adsorption characteristics and mechanism of PANF-ATL were evaluated. The Langmuir model and the pseudo-second-order model well described the adsorption of Au(Ⅲ) by PANF-ATL. The adsorption capacity of PANF-ATL obtained from Langmuir isotherm model towards Au(Ⅲ) was 130.58 mg/g (298 K). In addition, Au(Ⅲ) adsorbed on the fibers was completely eluted using a mixed solution of 4 mol/L HCl and 12% thiourea. It still has good adsorption performance after 5 adsorption-desorption cycles. Overall, PANF-ATL is a cost-effective adsorbent that can effectively adsorb Au(Ⅲ) in aqueous solution. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of chitosan oligosaccharides (COS)–nisin conjugates (COS‐N CON) on the quality changes of Collichthys niveatus during storage at 4°C. COS–N CON were prepared by heating the aqueous solution of COS and nisin together at 80°C for 24 hr. In order to control the degree of conjugation, the total concentration and pH of mixed solution were adjusted to 2% and 2.00, respectively. COS–N CON were identified by Fourier transform infrared (FT–IR) and X–ray diffraction analysis (XRD). During storage, COS–N CON treated samples showed retarded sensory and texture deterioration, with significantly slower increase rate of pH, total viable counts (TVC), and total volatile basic nitrogen (TVB–N). At the day 6, the TVC, TVB–N, and hardness of C. niveatus treated with distilled water reached 6 log10(CFU/g), 28 mg/100 g, and 15 g, respectively; while that in COS–N CON treated samples was 5.1 log10(CFU/g), 21 mg/100 g, and 18 g, respectively. Based on indicating parameters tested, it was revealed that the COS–N CON treatment could prolong the shelf life of C. niveatus by 2 days during chilled storage, compared to the chitosan oligosaccharides (COS)–nisin mixture (COS–N MIX). Practical applications: The novel preservation agent we created in this study could be considered as safe and renewable, which could be a great advantage in practical application. It was formed by conjugating chitosan oligosaccharides (COS) with nisin via Maillard reaction. Both COS and nisin were considered as green and renewable antimicrobial agents. Maillard reaction is one of the main reactions taking place in food that does not need catalyst and organic solvent. COS–nisin conjugates had a better effect on preservation of Collichthys niveatus, compared with COS–nisin mixtures, which indicating Maillard reaction could be the effective way in modifying the preservation properties of natural antimicrobial agents. [ABSTRACT FROM AUTHOR]

Abstract: A variety of ketones and internal alkynes are converted into isoquinolines and heterocyclic fused pyridines. [ABSTRACT FROM AUTHOR]