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Radionuclide extraction from wastewater is a long-term process, in which the study on the reuse and decomposition of adsorbents provides the ability to complete the post-treatment after adsorption. Herein, A novel biodegradable amidoxime chitosan has been synthesized through one-step without crosslinking agent and characterized by FT-IR, SEM, XPS, TGA and element analysis. The batch adsorption experiments of U(VI) and Th(IV) on AO-CTS adsorbent were studied and maximum adsorption of U(VI) and Th(IV) were 97 and 56 mg/g, respectively. The U(VI) and Th(Ⅳ) can be effectively desorbed from the AO-CTS materials at low acidity, The AO-CTS can be reused 6 times without reducing absorbency for U(VI) and Th(Ⅳ). When finish the adsorption process, the AO-CTS can be degraded by lysozyme at room temperature, there were no toxic or harmful substances are produced.

Internal contamination of actinides has been a long term concern for the medical treatment of people in nuclear accident scenarios, due primarily to their chemo- and radio-toxicity. So far, many ligands and functional nanomaterials have been designed to sequester actinides in vivo, however, little attention has been paid to reduce the injury induced by the internal exposure of actinides. Herein, we propose PEG grafted melanin nanoparticles (MNPs-PEG) as a bifunctional agent that can not only selectively sequester two different actinides (namely U and Th) at the same time, but also reduce the reactive oxygen species (ROS) level in U and Th contaminated cells. The adsorption experiments indicate that more than 99% of U and Th can be chelated selectively by MNPs-PEG in the presence of excess interfering ions. The in vitro decorporation assays show that the material can greatly reduce the deposition of U (77.5%) in NRK-52E cells and Th (75.8%) in AML-12 cells. In addition, ROS assays show that MNPs-PEG can almost reduce the intracellular ROS to a normal level, verifying its remarkable radical quenching ability. More importantly, an in vivo study demonstrated the effective sequestration capability of MNPs-PEG by reducing 33.1% and 45.4% of U from kidneys and bones, respectively, and 42.8% of Th from the liver of mice, simultaneously. Our results show that the MNPs-PEG exhibit clear advantages compared with the current decorporation agents in both actinide sequestration and radiation protection capabilities.

In this study, four functional β-cyclodextrin derivatives including amidoxime linear-linked and cross-linked β-cyclodextrin/acrylonitrile/acrylic terpolymer (l-CD-AO-AA and c-CD-AO-AA), citric acid cross-linked poly-β-cyclodextrin (PCD), amidoxime cross-linked β-cyclodextrin and acrylonitrile–acrylic block copolymer (CD-b-AO-AA) were synthesized and properties of β-CD derivatives were characterized by FT-IR, SEM, TGA and element analysis. The effect of solid liquid ratio of the adsorbents, ionic strength, pH, contact time, initial concentration of U(VI), adsorption temperature, selective adsorption for different metal ions and the reasonable desorption conditions were studied. It was found when content of U(VI) was 22 mg/L, the four functional materials l-CD-AO-AA, c-CD-AO-AA, PCD and CD-AO-b-AA completely adsorbed U(VI) at 0.06 g/L (R ≈ 97%), 0.10 g/L (R ≈ 96%), 0.08 g/L (R ≈ 94%) and 0.52 g/L (R ≈ 94%), respectively.

Modification of silica gel by butanedioic anhydride (SiO2–BDAH) results in efficient adsorbents for removal of U(VI), Th(IV), and Eu(III) from aqueous solutions. SiO2–BDAH was characterized by Fourier Transform infrared spectroscopy, elemental analysis, N2 adsorption–desorption isotherms, thermogravimetic analysis, and potentiometric titration. The effect of contact time, pH, and initial concentration of radioactive solutions and temperature on the adsorption capacity of the sorbent was investigated. The sorption equilibrium times of U(VI), Th(IV), and Eu(III) onto SiO2–BDAH were 1.5, 2, and about 10 h. The sorption percentages of U(VI), Th(IV), and Eu(III) increased with increased pH from 1 to 5. The sorption process of U(VI), Th(IV), and Eu(III) can be described by the Langmuir model, with sorption capacities of 5.10 × 10−5, 5.06 × 10−5, and 3.44 × 10−5 mol/L, respectively. The enthalpy and entropy changes were all positive, whereas the free energy changes were negative. This study indicated that SiO2–BDAH can remove U(VI) and Th(IV) at the same time in the presence of multiple ions from waste water quickly.

As the authors of the title paper [...]

Graphene oxide (GO) and its composite membranes have exhibited great potential for application in water purification and desalination. This article reports that a novel graphene oxide membrane (GOM) of ~5 &micro, m thickness was fabricated onto a nylon membrane by vacuum filtration and cross-linked by amino acids (L-alanine, L-phenylalanine, and serine). The GOM cross-linked by amino acids (GOM-A) exhibits excellent stability, high water flux, and high rejection to metal ions. The rejection coefficients to alkali and alkaline earth metal ions through GOM-A were over 94% and 96%, respectively. The rejection coefficients decreased with an increasing H+ concentration. Metal ions (K+, Ca2+, and Fe3+) can be inserted into GOM-A layers, which enlarges the interlayer spacing of GOM-A and neutralizes the electronegativity of the membrane, resulting in the decease in the rejection coefficients to metal ions. Meanwhile, GOM-A showed quite high antibacterial efficiency against E. coli. With the excellent performance as described above, GOM-A could be used to purify and desalt water.

Efficient and cost-effective removal of radioactive iodine anions from contaminated water has become a crucial task and a great challenge for waste treatment and environmental remediation. Herein, we present hexadecylpyridinium chloride monohydrate modified bentonite (HDPy-bent) for the efficient and selective removal of iodine anions (I

Technetium-99 (99Tc), as one of the important high-yield fission products, poses a significant threat to the environment and human health due to its radiotoxicity, long half-life, high solubility and mobility in the environment. Thus, removal of 99TcO4− from radioactive wastewater is considerably imminent for waste disposal and environment conservation. In this work, Hexadecylpyridinium Chloride Monohydrate modified bentonite (HDPy-bent) was synthesised and used as an adsorbent to remove 99TcO4−. The adsorption behaviours of ReO4− as an analogue for TcO4− were investigated as functions of contact time, solution pH, initial concentration, and competing anions using batch techniques. It is demonstrated that the HDPy-bent showed an excellent adsorption ability for ReO4− at the pH range of 2–11, fast adsorption kinetic (reaching equilibrium within 3 min at room temperature), and maintains desirable ReO4− adsorption in the presence of concomitant anions at an excessive concentration of 500 times (Cl−, HCO3−, NO3−, CO32−, SO42− and PO43−). As for adsorption mechanism, we propose the anion exchange process at low concentration of Re(VII) and precipitation reaction at high concentration, while the driving force of the high ReO4− adsorption ability is the interaction between ReO4− anion and pyridinium ring of HDPy+, which is confirmed by density functional theory (DFT) simulations. Additionally, DFT studies also shed light on the adsorption structure of HDPy+/ReO4− and the origin of adsorption selectivity. Moreover, four adsorption-desorption cycles suggest that the HDPy-bent has good durability and reusability. Furthermore, ReO4− can be removed completely and recovered fractionally by using the chromatography column packed with HDPy-bent from simulated groundwater samples. The work presented herein demonstrates a low-cost adsorbent which can efficiently remove 99Tc from contaminated water.

The β-cyclodextrin-graft-(maleic anhydride-co-acrylonitrule) copolymer (β-CD-g-(MAH-co-AN)) synthesized through radical polymerization reactions of β-cyclodextrin (β-CD) with maleic anhydride (MAH) and acrylonitrule (AN) in the special monomer proportion, chemically modify with amidoxime groups to obtained the new adsorbent, which was terms as amidoxime-functionalized β-cyclodextrin-graft-(maleic anhydride-co-acrylonitrule) copolymer (β-CD-g-(MAH-co-AO)). Based on the characteristic results of Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), X-ray Diffraction (XRD), and thermalgravity analysis (TGA) techniques, the grafted nitrile groups were successfully converted to amidoxime groups by reaction with hydroxylamine. In this report, the influence of different factors such as pH value and ionic strength, solid-liquid ratio, contact time, initial U(VI) concentration, and temperature on adsorption was investigated by a batch adsorption experiment. The adsorption process fitting results show that the adsorption followed the Langmuir isotherm model and the maximum adsorption capacity was 0.747 g/g at pH 4.0. In addition, the regeneration performance was investigated by varying the concentration of eluent, temperature, and contact time. Under the desorption condition of 0.10 M HNO3, the adsorbents can be reused 12 times in the case that the adsorption capacity was not significantly reduced. The functionalized copolymer exhibits high selectivity under circumstance of other co-existing ions is present in the solution.

The authors wish to make the following corrections to their paper [...]

Dempster-Shafer evidence theory (DSET) is a flexible and popular paradigm for multisource data fusion in wireless sensor networks (WSNs). This paper presents a novel and easy implementing method computing masses from the hundreds of pieces of data collected by a WSN. The transfer model is based on the Mahalanobis distance (MD), which is an effective method to measure the similarity between an object and a sample. Compared to the existing methods, the proposed method concerns the statistical features of the observed data and it is good at transferring multi-dimensional data to belief assignment correctly and effectively. The main processes of the proposed method, which include the calculation of the intersection classes of the power set and the algorithm mapping MDs to masses, are described in detail. Experimental results in transformer fault diagnosis show that the proposed method has a high accuracy in constructing masses from multidimensional data for DSET. Additionally, the results also prove that higher dimensional data brings higher accuracy in transferring data to mass.

Taking the width/depth ratio of a river channel as an independent variable, a variational analysis of basic flow relationships shows that alluvial-channel flow adjusts channel geometry to achieve stationary equilibrium when the condition of maximum flow efficiency (MFE) is satisfied. As a test of the veracity of MFE and to examine if this theory of self-adjusting channel morphodynamics can be practically applied to large river systems, this study examines the degree of correspondence between theoretically determined equilibrium channel geometries and actual measurements along the middle and lower Yangtze River. Using four different forms of the Meyer-Peter and Muller bedload relation and relations of flow continuity and resistance we show that the Meyer-Peter and Muller bedload relation modified on the basis of MFE theory predicts channel dimensions most accurately when applied to the middle and lower Yangtze River. This provides convincing evidence supporting MFE equilibrium theory . Copyright (c) 2014 John Wiley & Sons, Ltd.

A movable-bed physical model is presented to investigate characteristics of hydrodynamic and sediment transport (ST) in a planned excavating channel downstream the Fuhe River (FHR) and the Qinglan Lake (QLL), Jiangxi Province, China. The model is validated by the observed water level and velocity data during the low water period in May 13 and high water period in June 21 2014, respectively, which shows well agreements between simulated and observed data. With repeating 6-years cycle of the runoff discharge and suspended sediment concentration condition from the Lijiadu hydrological station downstream the FHR during 2006 and 2008∼2012, experiments are conducted to predict bed evolution process in the excavated channel and QLL after the implement. The hydrodynamic results indicate that the cross-section averaged velocity generally increases both in the QLL and upstream of the excavated channel during a 20-year return period flood. The ST results show that erosion develops mainly in the left side of the channel and deposition occurs slightly upstream of the QLL after 30 years. Some deposition becomes visible in the center of the QLL after 90 years, and a relatively stable balance between deposition and erosion is observed in the whole QLL after 150 years.

The cation transport behavior of thermally treated reduced graphene oxide membranes (GOMs) is reported. The GOMs were reduced by heat treatment at 25, 80, and 120 &deg, C and then characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy to determine oxygen group content, C/O ratio, and layer spacing. The permeation rates of various cations with different sizes and charge numbers through these membranes were measured to understand the effect of the cations on transport behavior. The results indicated that the cation transport through the membranes depended on the layer spacing of the membrane and ion size and charge. Cations of the same valence permeating through the same GOM could be differentiated by their hydration radius, whereas the same type of cation passing through different GOMs could be determined by the spacing of the GOM layers. The cation valence strongly affected permeation behavior. The GOM that was prepared at 120 &deg, C exhibited a narrow layer spacing and high separation factors for Mg/Ca, Mg/Sr, K/Ca, and K/Fe. The cations moving through the membrane could insert into the membrane lamellas, which neutralized the negative charge of the membrane, enlarged the layer spacing of the GOMs, and affected cation permeation.

Adsorption of U(VI) on purified kaolin was studied by batch methods under ambient conditions, including contact time, pH, fulvic acid, etc. Three kinetic models were used to model the kinetic adsorption which was very well described by the pseudo-second-order rate equation, and the activation energy of adsorption was 52.20 kJ/mol. The Freundlich and Dubinin–Radushkevich models fitted the experimental data better than the Langmuir model for the adsorption and desorption isotherms. The thermodynamic parameters indicated that the adsorption of U(VI) on kaolin was an endothermic and spontaneous process.

In this article, a Session Initiation Protocol (SIP)-based instant messaging system is proposed to give an open protocol for instant messaging software to communicate with multi-platform and multi-service interoperability. The system will solve the issue of compatibility between current, mainstream, communication software. The system is based mainly on a multi-media scheduling server. This article is focused on the design of the SIP channel module, the instant messaging module, and presence service module with the goal of eventually achieving the function of instant communication between clients.

A series of temperature-sensitive N,N-diethylacrylamide-co-acrylic acid microgels were synthesized by modified surfactant-free emulsion polymerization method and characterized by Fourier transform infrared spectroscopy, turbidimetric method, scanning electron microscopy (SEM), and dynamic light scattering (DLS) measurements. The SEM images showed that the as-synthesized microgels were monodispersed as spherical particles and the average size increased from 200 to 800 nm with the mole fraction of acrylic acid (AA) increasing from 0 to 0.40. Turbidimetric analysis and DLS investigation indicated that the volume phase transition temperature and the swelling ratio of the microgels had an upward trend that was associated with the higher incorporation of AA. Furthermore, horseradish peroxidase (HRP) was successfully immobilized on the microgel with the greatest swelling ratio (the mole fraction of AA equal to 0.40) to obtain an enzyme-microgel complex for the treatment of wastewater polluted by phenolic compounds. The immobilized HRP achieved a high removal efficiency of >96% toward phenol and was more thermostable and more easily stored and reused compared with free HRP.

2-((4-Methoxyphenoxy) carbonyl) benzoic acid, 2-(1-methoxyvinyl) benzoic acid and their rare earth complexes LnL(2)(OH).3H(2)O (Ln=La, Eu, Tb) were synthesized and characterized by means of elemental analysis, FTIR, (1)H NMR, UV and luminescence spectroscopy. The FTIR and (1)H NMR results show that the carboxylic groups in the complexes coordinated to the rare earth ions in the form of one dentate, and the ester carboxylic groups have taken part in the coordination. Among these complexes, Eu(III) complexes and Tb(III) complexes exhibit characteristic fluorescence with comparatively high brightness and good monochromaticity, which indicated that the ligands of HL(I) and HL(II) are good organic chromophore to absorb and transfer energy to metal ions.

A series of new complexes of poly(styrene-co-methacrylic acid) with Ln(III) (Ln = La, Eu, Tb) were synthesized and well characterized by means of elemental analysis, FTIR, differential scanning calorimetric (DSC) analysis, TG-DTA analysis, X-ray diffraction (XRD), and fluorescence determination. The elemental analysis and FTIR studies showed that a large part of carboxylic groups on the side chain of the copolymer are coordinated with Ln(III) ions. The TG-DTA and DSC analysis results indicated that the complexes have good thermal stability. XRD experiments showed that copolymers and the complexes are amorphous. Among these complexes, Eu(III) complexes and Tb(III) complexes exhibit characteristic fluorescence with comparatively high brightness and good monochromaticity. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 3388-3394, 2009

(E)-4-(4-Methoxyphenoxy)-4-oxobut-2-enoic acid and its Ce(IV), Th(IV), and UO2(II) complexes were synthesized and characterized by MS, elemental analysis, IR, UV, TG-DTA, and NMR. The complexes have composition [CeL2(OH)2 · 2H2O] · H2O, [ThL2(OH)2 · 2H2O] · H2O, and [UO2L2 · 2H2O] · H2O. Molar conductance data confirm that the three complexes are nonelectrolytes. The IR and NMR results show that the carboxylates coordinate to the metal ions bidentate, and the ester carboxylic groups do not take part in coordination. Luminescence spectra of the ligand and complexes in DMSO at room temperature were also studied showing strong luminescence of the metal ions.

A series of complexes of poly(N,N-diethylacrylamide-co-methacrylic acid) (PDEA-co-MAA) with Ln(III) (Ln = La, Eu, Tb) were synthesized and characterized by X-ray diffraction, elemental analysis, FT-IR and TG-DTA. The luminescence spectra of Eu(III) and Tb(III) complexes in solid state were also studied. The complexes exhibit strong characteristic luminescence of Eu(III) and Tb(III) ions, while the luminescence intensity depend on the content of DEA and Ln(III) ions.

(Z)-4-(4-Methoxyphenoxy)-4-oxobut-2-enoic acid and its solid rare earth complexes LnL3·2H2O (Ln = La, Eu, Tb) were synthesized and characterized by means of MS, elemental analysis, FTIR, 13C NMR and TG–DTA. The IR and 13C NMR results show that the carboxylic groups in the complexes coordinated to the rare earth ions in the form of a bidentate ligand, but the ester carboxylic groups have not taken part in the coordination. The luminescence spectra of Eu(III) and Tb(III) complexes in solid state were also studied. The strong luminescence emitting peaks at 616 nm for Eu(III) and 547 nm for Tb(III) can be observed, which could be attributed to the ligand has an enhanced effect to the luminescence intensity of the Eu and Tb.

Sediment transport and bed morphology at channel confluences with different confluence angles and discharge ratios are analyzed through a series of flume experiments. Bed topography and sediment transport rate are measured and results are compared among different conditions. Sediment transport is intermittent and pulsating as the tributary flow mixes with the mainstream, and the sediment transport rate goes up with the increase in discharge ratio and confluence angle. With no sediment supplied from upstream of the flume, a central scour hole will form along the shear plane and develop toward the right bank, and the depth of the central scour hole increases as the confluence angle and discharge ratio increase. With heavy upstream sediment supplement, deposition will happen in the separation zone and upstream of the confluence area because of the tributary. And the deposition height is related to the discharge ratio and confluence angle. Results indicate the significant impact of confluence geometry, sediment, and flow factors on fluvial processes.

In this report, the β-CD(AN-co-AA) hydrogel was used to remove the thorium(IV) [Th(IV)] from the water system, and the new adsorbent was characterized through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The influences of contact time, pH value, ionic strength, solid-liquid ratio, initial Th(IV) concentration, and temperature on Th(IV) adsorption onto the functional hydrogel were researched. The results showed that the experimental data followed the Langmuir isotherm and the maximum adsorption capacity (qmax) for Th(IV) was 692 mg/g at pH 2.95, which approached the calculated (qe) 682 mg/g. The desorption capacity of Th(IV) in different HNO3 concentrations ranging from 0.005 to 0.5 M was also studied, and the percentage of the maximum desorption was 86.85% in the condition of 0.09 M HNO3. The selectivity of β-CD(AN-co-AA) hydrogel was also be studied, the results indicated that this material retained the good adsorption capacity to Th(IV) even when the Ca2+, Mg2+, or Pb2+ existed in the system. The findings indicate that β-CD(AN-co-AA) can be used as a new candidate for the enrichment and separation of Th(IV), or its analogue actinides, from large-volume solution in practical application.

There is continuously increasing interest in research on multi-sensor data fusion technology. Because Dempster’s rule of combination can be problematic when dealing with conflicting data, there are numerous issues that make data fusion a challenging task, including the exponential explosion, Zadeh Paradox, and one-vote veto. These issues lead to a great difference between the fusion results and real results. This paper applies the idea of analyzing distance-based evidence conflicts, introduces the concept of vector space, and proposes a new cosine theorem-based method of identifying and expressing conflicting data. In addition, this paper proposes a new data fusion algorithm based on the degree of mutual support between beliefs, which is based on the Jousselme distance-based combination rule proposed by Deng et al. Simulation results demonstrate that the presented algorithm achieves great improvements in both the accuracy of identifying conflicting data and that of fusing conflicting data.