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The present paper is dedicated to the quantitative determination of oxygen-containing impurities in the LiF–NaF–KF eutectic using electrochemical (cyclic and square-wave voltammetry) and reduction melting methods. The LiF–NaF–KF melt was analyzed before and after purifying electrolysis. The amount of oxygen-containing impurities removed from the salt during purification was determined. It was found that after electrolysis, the concentration of oxygen-containing impurities decreased by 7 times. The results obtained via electrochemical techniques and reduction melting were well-correlated, which made it possible to evaluate the quality of the LiF–NaF–KF F melt. To verify the analysis conditions, mechanical mixtures of LiF–NaF–KF containing Li2O were analyzed using the reduction melting method. The oxygen concentration in the mixtures varied from 0.672 to 2.554 wt. %. Based on the analysis results, the dependence approximated by the straight line was obtained. These data may be used to draw calibration curves and to further develop the procedure of oxygen analysis of fluoride melts.

Ni-based metallic foams possessing large specific surfaces and open cell structures are of specific interest as catalysts or catalyst carriers for electrolysis of water. Traditional fabrication of Nickel foam limits the element modification choices to several inert transition metals only on polymer foam precursor and subsequent preparation of foam-based catalysts in aqueous solution or organic electrolyte. To expand the modification horizon, molten salt with wide electrochemical window and fast ion diffusion can achieve the reduction of highly active elements. Herein, we reported is a general and facile method to deposit directly of highly reactive element La and prepare hierarchical honeycomb LaNi5 alloy on Ni foam (ho-LaNi5/NF). This self-supporting electrode presents excellent electrical coupling and conductivity between the Ni foam and LaNi5, which provides a 3D self-supported heterostructure with outstanding electrocatalytic activity and excellent durability for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). It exhibits excellent overpotential (1.86 V) comparable to commercial coupled IrO2//Pt/C (1.85 V) at a high current density of 100 mA cm−2. This work may pave the way for fabricating novel 3D self-supported honeycomb alloy that can be applied as electrode for usage of clean energy.

Molten salt electrolysis is a vital technique to produce high-purity lanthanide metals and alloys. However, the coordination environments of lanthanides in molten salts, which heavily affect the related redox potential and electrochemical properties, have not been well elucidated. Here we explore the competitive coordination of chloride and fluoride anions towards lanthanide cations (La 3+ and Nd 3+ ) in molten LiCl-KCl-LiF-LnCl 3 salts by using electrochemical, spectroscopic , and computational approaches. Electrochemical analyses show that significant negative shifts in the reduction potential of Ln 3+ occur when F - concentration increases, indicating that the F - anions interact with Ln 3+ via substituting the coordinated Cl - anions, and confirm [LnCl x F y ] 3-x-y (y max =3) complexes are prevailing in molten salts. Spectroscopic and computational results on solution structures further reveal the competition between Cl - and F - anions, which leads to the formation of four distinct Ln(III) species: [LnCl 6 ] 3- , [LnCl 5 F] 3- , [LnCl 4 F 2 ] 3- and [LnCl 4 F 3 ] 4- . Among them, the seven-coordinated [LnCl 4 F 3 ] 4- complex possesses a low-symmetry structure evidenced by the pattern change of Raman spectra. After comparing the polarizing power (Z/r) among different metal cations, we conclude that Ln-F interaction is weaker than that between transition metal and F - ions.

In order to optimize the application of Al electrodes in pyrochemical reprocessing of spent nuclear fuel, the feasibility of porous Al electrodes to separate actinides-lanthanides (An-Ln) in LiCl-KCl eutectic melt was explored. The separation efficiencies and rates of U and lanthanides (La, Ce, Sm) on Al electrodes with regular and irregular and without pores were compared. U was selectively recovered in the form of U-Al alloys by controlling the potential (−1.2 V) on both Al rod and porous Al electrodes. X-ray diffraction (XRD) and scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS) showed that the obtained granular alloys were mainly Al3U and Al4U, and inductive coupled plasma optical emission spectrometry (ICP-OES) indicated that there was almost no Ln in the electrolysis products. Positively, the required separation time was greatly shortened, and the separation rate was effectively improved when porous Al electrodes were used. In addition, the Al honeycomb electrode with regular pores has better kinetic performance compared with Al foam electrodes with irregular pores. The results indicate that the specially designed porous Al electrodes may have a good application prospect for the separation of An-Ln in the pyrochemical reprocessing of spent nuclear fuel.

Because H2O2 is thermally unstable, it seems to be difficult to synthesize peroxides at elevated temperatures. We describe here the in situ generation of peroxide that is incorporated in a new uran...

The separation of actinides has a vital place in nuclear fuel reprocessing, recovery of radionuclides, and remediation of environmental contamination. Here we propose a new paradigm of nanocluster-based actinide separation, namely, nanoextraction, that can achieve efficient sequestration of uranium in an unprecedented form of giant coordination nanocages using a cone-shaped macrocyclic pyrogallol[4]arene as the extractant. The U24-based hexameric pyrogallol[4]arene nanocages with distinctive [U2(PG)2] binuclear units (PG = pyrogallol) that rapidly assembled in situ in monophasic solvent were identified by single-crystal X-ray diffraction, MALDI-TOF mass spectrometry, NMR spectroscopy, and small-angle X-ray and neutron scattering. Comprehensive biphasic extraction studies showed that this novel separation strategy has enticing advantages such as fast kinetics, high efficiency, and good selectivity over lanthanides, thereby demonstrating its potential for efficient separation of actinide ions.

It is essential to keep the balance among rolling resistance, wet skid resistance and wear resistance (the so-called devil's triangle) of tire treads so as to ensure the reliability and safety of the vehicles. For this purpose, hexamethyl-disiloxane (HMDS) and carboxylated polyethylene vinyl acetate copolymer (EVA, emulsion polymer latex) were used to modify nanosilica by in situ surface-modification method, thereby obtaining surface-capped nanosilica possessing good compatibility and strong interfacial interactions with rubber matrix. The surface-capped nanosilica of the above both modifications were introduced into the blend of solution polymerized styrene butadiene rubber (SSBR) and butadiene rubber (BR), and its effect on the mechanical properties and wear resistance of the SSBR/BR-matrix nanocomposites was investigated. The results indicated that both HMDS and EVA contribute to enhancing the compatibility and interfacial interactions of nanosilica with the rubber matrix, which is favorable for improving the mechanical properties and wear resistance of SSBR/BR-matrix nanocomposites. Particularly, HMDS can endow the rubber-matrix nanocomposites with increased wet skid resistance, and EVA can ensure the low rolling resistance of the nanocomposites. Therefore, the SSBR/BR blend filled with HMDS–SiO2–EVA possesses the desired mechanical properties and wear resistance and shows promising prospective as a candidate material for fabricating high-performance tire tread.

The purpose of this study was to assess the value of metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF) for the diagnosis of severe respiratory diseases based on interpretation of sequencing results. BALF samples were harvested and used for mNGS as well as microbiological detection. Infectious bacteria or fungi were defined according to relative abundance and number of unique reads. We performed mNGS on 35 BALF samples from 32 patients. The positive rate reached 100% in the mNGS analysis of nine immunocompromised patients. Compared with the culture method, mNGS had a diagnostic sensitivity of 88.89% and a specificity of 74.07% with an agreement rate of 77.78% between these two methods. Compared with the smear method and PCR, mNGS had a diagnostic sensitivity of 77.78% and a specificity of 70.00%. In 13 cases, detection results were positive by mNGS but negative by culture/smear and PCR. The mNGS findings in 11/32 (34.4%) cases led to changes in treatment strategies. Linear regression analysis showed that diversity was significantly correlated with interval between disease onset and sampling. Dynamic changes in reads could indirectly reflect therapeutic effectiveness. BALF mNGS improves sensitivity of pathogen detection and provides guidance in clinical practice. Potential pathogens can be identified based on relative abundance and number of unique reads. Electronic supplementary material The online version of this article (10.1007/s10096-019-03734-5) contains supplementary material, which is available to authorized users.

The arylalkylamine N-acetyltransferase (AANAT) enzymes catalyze the acetyl-CoA-dependent acetylation of an amine or arylalkylamine, which is involved in important biological processes of insects. Here, we carried out the molecular and biochemical identification of an arylalkylamine N-acetyltransferase (AANAT) from the oriental fruit fly, Bactrocera dorsalis. Using a bacterial expression system, we expressed and purified the encoded recombinant BdorAANAT1-V3 protein. The purified recombinant protein acts on a wide range of substrates, including dopamine, tyramine, octopamine, serotonin, methoxytryptamine, and tryptamine, and shows similar substrate affinity (i.e., K

The applications of most fluorescent probes available for Glutathione S-Transferases (GSTs), including NI3 which we developed recently based on 1,8-naphthalimide (NI), are limited by their short emission wavelengths due to insufficient penetration. To realize imaging at a deeper depth, near-infrared (NIR) fluorescent probes are required. Here we report for the first time the designing of NIR fluorescent probes for GSTs by employing the NIR fluorophore HCy which possesses a higher brightness, hydrophilicity and electron-deficiency relative to NI. Intriguingly, with the same receptor unit, the HCy-based probe is always more reactive towards glutathione than the NI-based one, regardless of the specific chemical structure of the receptor unit. This was proved to result from the higher electron-deficiency of HCy instead of its higher hydrophilicity based on a comprehensive analysis. Further, with caging of the autofluorescence being crucial and more difficult to achieve via photoinduced electron transfer (PET) for a NIR probe, the quenching mechanism of HCy-based probes was proved to be PET for the first time with femtosecond transient absorption and theoretical calculations. Thus, HCy2 and HCy9, which employ receptor units less reactive than the one adopted in NI3, turned out to be the most appropriate NIR probes with high-sensitivity and little nonenzymatic background noise. They were then successfully applied to detecting GST in cells, tissues and tumor xenografts in vivo. Additionally, unlike HCy2 with a broad isoenzyme selectivity, HCy9 is specific for GSTA1-1, which is attributed to its lower reactivity and the higher effectiveness of GSTA1-1 in stabilizing the active intermediate via H-bonds based on docking simulations., An abnormal and intriguing phenomenon that the fluorophore's electron-deficiency could affect a probe's performance is now revealed for the first time.

Background Metazoan guts are in permanent contact with microbial communities. However, the host mechanisms that have developed to manage the dynamic changes of these microorganisms and maintain homeostasis remain largely unknown. Results Serotonin (5-hydroxytryptamine [5-HT]) was found to modulate gut microbiome homeostasis via regulation of a dual oxidase (Duox) gene expression in both Bactrocera dorsalis and Aedes aegypti. The knockdown of the peripheral 5-HT biosynthetic gene phenylalanine hydroxylase (TPH) increased the expression of Duox and the activity of reactive oxygen species, leading to a decrease in the gut microbiome load. Moreover, the TPH knockdown reduced the relative abundance of the bacterial genera Serratia and Providencia, including the opportunistic pathogens, S. marcescens and P. alcalifaciens in B. dorsalis. Treatment with 5-hydroxytryptophan, a precursor of 5-HT synthesis, fully rescued the TPH knockdown-induced phenotype. Conclusions The findings reveal the important contribution of 5-HT in regulating gut homeostasis, providing new insights into gut–microbe interactions in metazoans.

Both Al and Ga have exhibited excellent performance, respectively, for the An/Ln separation based on molten salt electrolysis, and the Al-Ga composite cathode may have superior properties. Therefore, in this work, the electrochemical behaviors of Ce (III) on the binary Al-Ga electrode were systematically explored by co-reduction of Ce (III), Al (III) and Ga (III) on a W electrode. A new oxidation signal of Al 2 Ga 2 Ce ternary intermetallic compound was successfully detected. In addition, for comparison, the co-reduction behaviors of Ce (III) with Al (III) and Ce (III) with Ga (III) on an inert tungsten electrode were also investigated. The results showed that different kinds of alloys are formed on the surface of W electrode. Finally, several typical Ga-Ce and Al-Ga-Ce intermetallic compounds were obtained by potentiostatic electrolysis and the deposited products were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDS).

The electrochemical and thermodynamic properties of Pr on a liquid Cd electrode and the formation of Cd-Pr intermetallic compounds were systematically studied by a series of electrochemical techniques in LiCl-KCl eutectic. The activity coefficient of Pr in the liquid Cd was determined by galvanostatic intermittent titration and in-situ open circuit chronopotentiometry at various temperatures. The measurement of electromotive force was conducted to calculate the partial molar Gibbs free energies of Pr in two phase coexisting states. In addition, the thermodynamic parameters of seven Cd-Pr intermetallic compounds such as the Gibbs free energy, enthalpy and entropy of formation were also determined. The deposited Cd-Pr alloy sample was prepared by galvanostatic electrolysis and further characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDS). The dissolution behavior of Cd-Pr alloy as an anode material was also evaluated by monitoring the variation of anodic potential.

The electrochemical behavior of Th(IV) on a bismuth electrode in LiCl–KCl eutectic was investigated by various electrochemical techniques, aiming at in-depth elucidation of basic electrochemical and thermodynamic properties of Th in molten salt. The results of cyclic voltammetry and coulometric titration indicated that the reduction of Th(IV) on a liquid Bi electrode occurred at −0.92 V (vs. Ag/AgCl) and was a one-step process with four electrons transferred. In addition, thermodynamic properties of Th in liquid Bi medium were evaluated by coulometric titration method in the temperature range from 723 to 798 K. The redox peaks of Bi2Th intermetallic compound were detected at −1.13 and −1.05 V, and the corresponding Gibbs free energy of formation was measured by open circuit chronopotentiometry (OCP). Finally, galvanostatic electrolysis (GE) was conducted on a liquid Bi electrode to extract Th from molten salt at 773 K. X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) were applied to characterize the composition and morphology of the products, and revealed the formation of Bi2Th intermetallic compound.

Developing necessary reprocessing techniques to meet the remarkable increase of spent nuclear fuels (SNFs) is crucial for the sustainable development of nuclear energy. This review summarizes recent research progresses related to the SNF reprocessing in China, with an emphasis on actinides separation over lanthanides through three different techniques, hydrometallurgical reprocessing, pyrometallurgical processes, and selective crystallization based separation. Some future perspectives with respect to advanced actinide separation are also given.

γδT cells are an important source of IL-17A and play an anti- or protumor role depending on the surrounding microenvironment. The precise role of γδT cells in the development of malignant pleural effusions (MPE) remains unknown. Using flow cytometry, we analyzed the distribution and differentiation of γδT cells in wild-type (WT) and IL-10-∕- mice. We carefully elucidated the influence of γδT cells on the formation of MPE by depleting γδT cells from WT, IL-10-∕-, and IL-17a-∕- mice. The distribution of γδT17 cells in human MPE and peripheral blood was also determined. Our data showed that both γδT cells and IL-17A-producing γδT (γδT17) cells accumulated in murine MPE, and IL-10 deficiency enhanced their accumulation. γδT cells were the main source of IL-17A in MPE for both WT and IL-10-∕- mice. IL-10 inhibited the chemotactic response of γδT cells to MPE and the proliferation of these cells. IL-10 suppressed γδT cell secretion of IL-17A via RORγt. The ablation of γδT cells accelerated MPE accumulation in both WT and IL-10-∕- mice, but it did not influence MPE accumulation in IL-17a-∕- mice. Patients with higher frequencies of γδT17 cells had significantly longer survival times than patients with lower frequencies of γδT17 cells. Taken together, our data demonstrate that γδT17 cells play an inhibitory role in the progression of MPE, and the accumulation of γδT17 cells in MPE is suppressed by IL-10.

The cathodic collection efficiency (CCE) for the exhaustive electrolysis of uranium is very low; however, determination of the mechanism responsible for this phenomenon has been hindered by the lack of information about the uranium species present in molten salts. Herein, we used in situ X-ray absorption spectroscopy and quasi in situ electronic absorption spectroscopy to study the chemical speciation of uranium during the electrolysis process. For the first time, uranium was revealed to be continuously converted between [UCl6]2− and [UCl6]3−, leading to problematic cyclic electrolysis. This cyclic electrolysis process was the main cause of the low CCE during exhaustive electrolysis, and also hindered the full recovery of uranium. To eliminate this cyclic electrolysis process, we adopted a sacrificial active lanthanum metal anode. The lanthanum metal dissolved at the anode to form La3+ ions, which hindered the conversion between [UCl6]2− and [UCl6]3−. Thus, the uranium cycle between the cathode and the anode was eliminated, resulting in a significant improvement in the CCE for exhaustive electrolysis. Keywords: Uranium, Cyclic electrolysis, Pyrochemical process, Energy

s The composition of electrolytes is one of the key factors that determine the electrochemical properties of elements in an electrochemical process. In this work, the influence of LiF introduction into LiCl-KCl molten salt on the electrochemical behavior and coordination properties of uranium was studied by combining electrochemical and spectroscopic techniques as well as ab initio molecular dynamic simulations. The results showed that, compared to coordination with U(III), F− ion readily coordinates with U(IV), which has a smaller ion radius and larger charge density. The involvement of F− ion in coordination makes U(IV) complex more stable, and the equilibrium potential of U(IV)/U(III) shifts to the negative direction, closer to that of U(III)/U(0). In the presence of a large amount of Cl− ions, F− ions cannot completely replace the role of Cl− ions, so U(IV) and U(III) prefer to form UCl3F32− and UCl5F3− complexes, respectively. Anyway, the involvement of F− ion in coordination may lead to smaller volume of uranium complexes in melt, resulting in slight increase of the diffusion coefficient of U(IV). In addition, the effect of substitution of Cl− by F− ions on the crystal field splitting energy of U(III) complex was observed. The in-depth understanding of the relationship between the coordination structure and electrochemical properties of uranium in melt will be of much significance for the design and control of more efficient electrochemical process for actinide separation.

Pyroprocessing technology with molten salt electrolysis as the core is a promising technology for the reprocessing of spent fuel. In this work, the electrochemical reduction mechanism and kinetic properties of Nd3+ on various electrodes (inert W and reactive Al, Ga, Bi, Cd, Zn, Pb, and Sn electrodes) were systematically investigated and compared in LiCl-KCl eutectic melts using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and Tafel techniques. The electrochemical reduction of Nd3+ was a two-step process on the W electrode including Nd3+→Nd2+ and Nd2+→Nd, while it became a one-step process involving three electrons on the reactive electrodes with obvious depolarization effects. Furthermore, the connections between the reduction potentials of Nd3+ on these reactive cathodes and the formation energies of the electrode-rich alloy phases (Al11Nd3, Cd11Nd, Pb3Nd, Zn17Nd2, Ga6Nd, Sn3Nd, BiNd2) were established. After evaluating the physicochemical, depolarization and kinetic properties of these reactive electrodes, liquid Cd was considered as the most favorable material for the electrochemical extraction of Nd. In addition, Al, Cd, and Bi are also promising candidates for An / Ln separation.

Traditionally, the dissolution of UO2-based spent fuels in molten chlorides is difficult and usually conducted under strict controlling environment. Here, we report a particularly simple method utilizing NH4Cl for the dissolution of UO2 and rare earth oxides (RExOy), which is of potential interest for the pyrochemical reprocessing of UO2-based spent fuels. In this work, NH4Cl is conveniently introduced on the surface of LiCl-KCl melt. The results show that both the UO2 and RExOy can be successfully dissolved into the LiCl-KCl melt in air atmosphere with the assistance of NH4Cl. In addition, the dissolution process and mechanisms are studied in detail by electrochemical and spectroscopic methods. For the dissolution of UO2, UO2Cl2 is finally formed with the intermediates of U3O8 and UO3, and the obtained concentration of UO22+ is about 0.64% in the melt. In contrast, for the dissolution of RExOy, RECl3 is ultimately produced with the main intermediate of RECl3žxNH4Cl.

This work presents the electrochemical properties of gadolinium (Gd), a significant rare earth element in spent nuclear fuel (SNF), in the LiCl KCl eutectic. To explore thermodynamic properties of Gd at the liquid gallium (Ga) electrode, experiments were performed both on the inert tungsten (W) and liquid gallium (Ga) electrode at different temperatures in a range from 723 to 823 K, which show that the Gd metal can be oxidized to Gd (III) by exchanging of 3 electrons. Electrochemical techniques including cyclic voltammetry (CV), open circuit potential (OCP), potentiostatic electrolysis and galvanostatic electrolysis were utilized to detect the electrochemical behavior and evaluate standard apparent potential of the Gd(Ⅲ)/Gd couple, and E Gd(Ⅲ) / Gd * = − 3.456 + 6.2 × 10 − 4 T ( ± 0.046 ) ( vs C l 2 / C l − ) is obtained. In addition, electromotive force (EMF) and coulometric titration were employed to calculate the activity and activity coefficient of Gd in metal Ga. After calculation, the activity is 1 . 791 × 10 − 15 at 723 K and function of activity coefficient and temperature is lg γ = 3.485 − 10927 / T ( ± 0.0875 ) .

This paper reports the direct separation of U from lanthanides (Ln) in oxide mixtures in LiCl-KCl eutectic, a method that could simplify the pyrometallurgical reprocessing of UO 2 -based spent fuels. In the melt, the mixture of UO 2 and lanthanide oxides (Ln 2 O 3 /LnO 2 ) was chloridized by AlCl 3 , and then U was selectively recovered by forming U-Al alloys through the redox reactions of U(IV)/U(III) and U(III)/Al x U. The results showed that U could be efficiently separated from lanthanides with high separation factors ( SF U/La = 1.1 × 10 4 , SF U/Ce = 1.6 × 10 5 , and SF U/Sm = 2.5 × 10 4 ). X-ray diffraction analysis indicated the predominant separation products to be Al 3 U and Al 4 U, whereas the real extraction rate of U was probably affected by trace amounts of O 2− in the melt. For the first time, single-cell operation to separate U from Ln in mixed oxides is shown to be feasible by using AlCl 3 as chlorination agent followed by electrodeposition.

This work presents the electrochemical behaviors of Pr (III) on a liquid Bi electrode and the formation of Bi-Pr intermetallics in LiCl-KCl eutectic melt. Galvanostatic voltammetry and open circuit chronopotentiometry techniques were employed to determine the apparent standard potential of Pr(III)/Pr couple. The reduction of Pr (III) on the liquid Bi electrode is a one step process with three electrons transferred. The activity coefficient of Pr in liquid Bi was also determined by coulometric titration and in-situ open circuit chronopotentiometry at the temperature range of 723 to 813K. In addition, the signals of five intermetallic compounds corresponding to the Bi-Pr binary phase diagram were successively detected by a series of electrochemical techniques. Thermodynamic properties for the formation of Bi-Pr intermetallic compound were measured by open circuit chronopotentiometry. The activities and partial molar Gibbs free energies of Pr in the two phase coexisting system were obtained, from which the Gibbs free energy, the enthalpy and entropy of formation were also calculated. (C) 2018 The Electrochemical Society.

Muscarinic acetylcholine receptors (mAChRs) play important roles in the insect nervous system. These receptors are G protein-coupled receptors, which are potential targets for insecticide development. While the investigation of pharmacological properties of insect mAChRs is growing, the physiological roles of the receptor subtype remain largely indeterminate. Here, we identified three mAChR genes in an important agricultural pest Bactrocera dorsalis . Phylogenetic analysis defined these genes as mAChR-A, -B, and -C. Transcripts of the three mAChRs are most prevalent in 1-d-old larvae and are more abundant in the brain than other body parts in adults. Functional assay of Bdor-mAChR-B transiently expressed in Chinese hamster ovary cells showed that it was activated by acetylcholine (EC 50, 205.11 nM) and the mAChR agonist oxotremorine M (EC50, 2.39 μM) in a dose-dependent manner. Using the CRISPR/Cas9 technique, we successfully obtained a Bdor-mAChR-B knockout strain based on wild-type (WT) strain. When compared with WT, the hatching and eclosion rate of Bdor-mAChR-B mutants are significantly lower. Moreover, the crawl speed of Bdor-mAChR-B knockout larvae was lower than that of WT, while climbing performance was enhanced in the mutant adults. Adults with loss of function of Bdor-mAChR-B showed declined copulation rates and egg numbers (by mated females). Our results indicate that Bdor-mAChR-B plays a key role in the development, locomotion, and mating behavior of B. dorsalis.

The aim of this work is to explore the electroseparation of uranium from lanthanides (La, Ce, Pr, Nd and Sm) on a liquid gallium electrode. Cyclic voltammetric results showed that in multi-component melt systems (U/Nd, U/La-Ce-Nd, and U/La-Ce-Pr-Nd-Sm), the reduction potentials of each lanthanides on the Ga cathode are identical and cannot be distinguished and resolved. The peak potential differences between the lanthanides and uranium are all at about 250 mV. The practical electroseparations in U/Nd, U/La-Ce-Nd and U/La-Ce-Pr-Nd-Sm systems were carried out by applying different electrochemical techniques as galvanostatic, potentiostatic and current pulse electrolysis. After electrolysis, the ICP-AES technique was used to determine the composition of molten salt and alloy deposits, and the actual separations factor of U over lanthanides in these multi-component systems were calculated and compared. The results showed that the separation factors of U/La and U/Sm can be both up to 1000, whilst that of U/Nd is relatively low with an average value of about 350. In addition, the separation factor obtained by the current pulse electrolysis is larger than that of galvanostatic and potentiostatic method, and the potentiostatic electrolysis provides the lowest one.

Electrochemical properties of rare-earth elements in the LiCl-KCl eutectic are important for the pyrometallurgical recycling process of spent nuclear fuels. In this work, the electrochemical properties of Tb (III)/Tb (0) couple were studied by the cyclic voltammetry (CV) at a liquid Zn pool electrode. The results showed that this electrochemical reaction is quasi-reversible with mixed reversible diffusion control and the charge transfer control. The diffusion coefficient of Tb (III) was determined to be in the order of ~10−5 cm2 s−1. Moreover, kinetic parameters, such as the standard rate constants ( k s) and charge transfer coefficient ( α ) for the electroreduction of Tb (III) to Tb (0) at the liquid Zn electrode, were calculated by the Nicholson method at 873 K. Additionally, it was found that Tb-Zn intermetallic compounds were easily to be formed in the measurements. Hence, the reduction process of Tb (III)/Tb (0) couple on the Zn-coated Mo electrode was also studied to obtain more information of the Tb-Zn intermetallic compounds. Electrochemical signals stemming from various intermetallic compounds associated with TbZn12, Tb2Zn17, Tb13Zn58, Tb3Zn11, TbZn3, TbZn2 and TbZn, were observed. The thermodynamic data were thereafter estimated by applying the emf method at 823–923 K. The standard formation Gibbs energies and the standard equilibrium constant of each Tb-Zn intermetallic compounds were also calculated. Finally, enthalpies and entropies of formation and the apparent standard potentials of various Tb-Zn intermetallic compounds were also obtained.

This work presents a comprehensive study for the electrochemical behaviors of zirconium in LiCl-KCl eutectic. The effects of stirring, temperature and Zr concentration on the electrode reactions, the ZrCl4 sublimation from the melt, microcosmic morphologies of Zr deposits (ZrCl and Zr) obtained at different potential and temperature have been investigated. The behaviors of Zr(IV), on a large concentration range from 0.13% to 2.28% in melt, show a multiple-step reaction involving Zr(IV), Zr(II), ZrCl and Zr species. Temperature plays a crucial role on the changes of Zr(IV) reduction behavior on the solid electrode. The Zr(IV)/ZrCl couple is more easily observed at lower temperature and gradually diminishes with the increase of temperature. The Zr(IV)/Zr(II) and Zr(II)/Zr reactions are predominant on the W electrode at higher temperatures. At 673 K, a layered structure of insoluble ZrCl formed by potentiostatic electrolyses at 1.1 V was visualized by scanning electron microscopy-energy dispersive X-ray (SEM-EDS), while only Zr metal particles was observed at higher temperature than 773 K. An evolution of the Zr-based structure and size corresponding to the ZrCl and Zr metal based on different potentiostatic electrolysis was observed. The average particle size of the Zr metalparticles increases with the increase of temperature.

Epithelial cell transforming sequence 2 (ECT2) is a guanine nucleotide exchange factor and its expression is associated with the development of malignant tumor types. However, to the best of our knowledge, there is no information on the role of ECT2 in the development and progression of laryngeal squamous cell carcinoma (LSCC). The present study aimed at investigating the expression pattern and potential role of ECT2 in the development and progression of LSCC. The expression of ECT2 in 81 pairs of LSCC and adjacent non-tumor tissues was characterized by immunohistochemistry and reverse transcription-quantitative polymerase chain reaction. ECT2 expression was upregulated in LSCC tissues and associated significantly with poor differentiation, higher stages, lymph node metastasis and poor survival in the sample population. The relative expression levels of ECT2 mRNA transcripts were correlated with the intensity of anti-ECT2 staining in 25 ECT2+LSCC specimens selected randomly. These results indicated that ECT2 expression was crucial for the progression of LSCC and may serve as a biomarker for the diagnosis and prognosis of LSCC.

Background Bactrocera dorsalis (Hendel) is the main fruit fly pest of tropical and subtropical countries. The application of insecticides to manage this pest has led to serious resistance problems; therefore, new ways to control B. dorsalis are required. Pathogenic bacteria are sources of biocontrol agents for pest management. Results We determined that a pathogenic bacterial strain, Serratia marcescens PS-1, isolated from a moribund striped flea beetle (Phyllotreta striolata), was lethal to B. dorsalis adults following ingestion. Histological analyses revealed that PS-1 damaged the intestinal epithelium, resulting in cell death within 24 h. We then generated a gut transcriptomic data set using RNA-Seq at two time points (6 and 24 h) after PS-1 infection. We found that genes encoding the peritrophic matrix constituent were down-regulated, whereas genes involved in lipid and glycan metabolism, and renewal of the gut epithelium, along with genes encoding digestive enzymes and stress response factors, were up-regulated. In addition, 14 cecropin genes were identified and cloned from B. dorsalis. To our knowledge, the number of cecropins identified in the present study is greater than that reported in the insects of earlier studies. Moreover, some of the cecropins identified were significantly down-regulated after PS-1 treatment. Conclusion Our findings provide new insights into the insect gut response to pathogenic bacterial invasion and may aid the development of new strategies for the biological control of B. dorsalis. © 2019 Society of Chemical Industry.

Electrochemical studies of UCl3 and LnCl3 (Ln: La, Ce, Pr, Nd) in LiCl–KCl melt were performed on inert tungsten and reactive bismuth electrodes. Galvanostatic pulse (GP) and electrochemical impedance spectroscopy (EIS) were carried out to investigate the exchange current density j0 of UCl3/U on liquid Bi electrode at the temperature range of 723–873 K. The impedance data were well fitted with the equivalent circuit. The relationship between j0 and the temperature was determined to model the electrowinning by using liquid Bi electrode. In addition, the electrochemical separation in low concentration uranium from multi-component lanthanide chlorides was demonstrated on liquid Bi electrode. Three electrochemical techniques, including coulometric titration, galvanostatic electrolysis and potentiostatic electrolysis, were applied for the separation of uranium. In which, the coulometric titration showed good separation results. The separation of uranium from lanthanides in terms of mole ratio (U/Ln) was determined, and the different values were discussed in detail. In general, the data from this work can provide theoretical reference for the separation process of various metals by electrochemistry.

A series of nano-silicas with varying content of grafted hexamethyl disilazane (HMDS) modifier were prepared by liquid phase in-situ surface modification method in combination with granulation technology. The effect of the as-prepared nano-silica as fillers on the mechanical properties and abrasion resistance of solution polymerized styrene butadiene rubber (SSBR)/butadiene rubber (BR)-matrix composites were investigated. It was found that the content of the surface hydroxyl of the as-prepared organic-inorganic hybrids, HMDS-capped nano-silica, can be well tuned by adjusting the modifier dosage. The resultant HMDS-capped nano-silica have greatly improved dispersibility in rubber matrix as well as highly enhanced compatibility and interfacial interaction with the rubber matrix, which is favorable for improving the mechanical properties and abrasion resistance of the SSBR/BR-matrix composites. Particularly, the SSBR/BR-matrix composite filled with HMDS-capped nano-silica obtained at a modifier dosage of 20% (mass fraction) exhibits greatly improved mechanical properties and wet skid resistance(12.0%) as well as significantly reduced rolling-resistance(30.4%) and Akron abrasion(18.4%) as compared with the one filled with unmodified nano-silica. The present approach, with good access to surface chemistry manipulation of nano-silica, could help to promote the application of functionalized nano-silica in tire industry.

As a typical uranium oxide, the electrochemical behaviors of U3O8 in molten salt have attracted many research endeavors, but its dissolution behavior and related mechanism in molten salt has been less well understood. In this work, we reported the dissolution of U3O8 in LiCl-KCl eutectic with the assistance of NH4Cl, which has potential significance for the pyrochemical reprocessing of spent oxide fuels. The spectroscopic techniques such as fluorescence emission spectroscopy, UV-Vis absorption spectroscopy, and X-ray Absorption Fine Structure (XAFS) were used to determine the chemical species during the dissolution process of U3O8. The results show that U3O8 can be completely dissolved in molten salt under the air atmosphere, and it exists in the form of [UO2Cl4]2−. In contrast, under an argon atmosphere, the soluble [UO2Cl4]3− and insoluble UO2 were detected as the main products.

In this work, the diffusion coefficients of Ho3+ at the Zn pool electrode and the Zn film electrode were firstly studied. Both semi-differential and semi-integral techniques were employed to analysis the cyclic voltammetry (CV) curves for the determination of the diffusion coefficients. The results showed that diffusion coefficients at Zn pool electrode and the Zn film electrode were close to each other by semi-differential technique. In addition, the co-reduction behaviors of Ho3+ and Zn2+ on W electrode were also investigated to determine the reactions of Ho with the Zn electrode. It was found that HoxZny intermetallic compounds would be formed by the co-reduction process, and the compositions of these HoxZny intermetallic compounds were estimated by the accumulated coulomb numbers of the relative anodic peaks on the CV curves. Moreover, electrodeposition of Ho3+ was carried out on both the inert W electrode and the liquid zinc electrode. X-ray diffraction (XRD) results showed that Ho2Zn17 and HoZn3 were obtained on the W electrode by the co-reduction process, whilst Ho2Zn17 was gained at the liquid zinc electrode by underpotential-deposition process. The microstructures of the intermetallic compounds were characterized by scanning electron microscopy (SEM).

This work presents a study of electrochemistry of uranium on a liquid gallium in LiCl-KCl eutectic by applying a series of electrochemical techniques. The electrochemical window of the Ga electrode in LiCl-KCl eutectic is about -1.40 to -0.35 V vs. Ag/AgCl. The reduction of U(III) on liquid gallium starts at -0.86 V and is a one step process with the transfer of three electrons. The co-reductive cyclic voltammograms of U(III) and Ga(III) present a couple of sharp redox peaks at about -0.95 and -0.84 V, corresponding to the formation and dissolution of the intermetallic compound UGa3. In addition, the reduction of Ga(III) in LiCl-KCl melt is a two-step process: Ga(III). Ga(I). Ga. The activity coefficient and solubility of U in liquid Ga at the temperature range from 673 to 823 K were determined by coulometric titration and open circuit potential respectively. The Gibbs free energy for the formation of UGa3 was also calculated. The intermetallic compound UGa3 was deposited by potentiostatic electrolysis at -1.0 V in the LiCl-KCl -GaCl3-UCl3 and LiCl-KCl-UCl3 melt on solid W and liquid Ga electrodes at 773 K, respectively. The electrolysis efficiency is about 97% based on the ICP result. Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy (SEM-EDS) and X-ray diffraction (XRD) characterizations further identified the formation of UGa3. (C) 2016 The Electrochemical Society. All rights reserved.