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The application of Pr-Nd-Dy alloy in the field of high-performance Nd-Fe-B permanent magnet materials has great potential. The composition of the PrF3-NdF3-DyF3-LiF (PND-LiF) electrolyte system used in the production of Pr-Nd-Dy alloys, the distribution of F, Li, RE and other elements in the electrolyte and their occurrence state were studied in this paper. The effect of temperature and lithium fluoride addition on electrolyte conductivity was revealed using the continuous conductivity cell constant (CVCC) method. The thermal analysis method was used to study the influence of lithium fluoride addition on the electrolyte's liquidus temperature and the optimal process conditions for the production of Pr-Nd-Dy alloy were determined. The results show that the overall distribution of praseodymium neodymium fluoride and lithium fluoride is uniform in the electrolyte and dysprosium fluoride is distributed between praseodymium-neodymium fluoride and lithium fluoride. Praseodymium-neodymium oxide is embedded in praseodymium neodymium fluoride in spotty pattern. The electrolyte's conductivity is increased as the temperature and lithium fluoride addition are going up, while the liquidus temperature is going down with increasing lithium fluoride addition. The best electrolysis process conditions for the PND-LiF system to produce praseodymium neodymium dysprosium alloy are as follows: temperature 1050 °C, 15.56 wt% PrF3-62.22 wt% NdF3-11.11 wt% DyF3-11.11 wt% LiF.

Spent pot lining (SPL) from aluminum reduction cells is considered to be hazardous materials due to containing a large amount of soluble fluoride salts and trace toxic cyanides. The distribution of fluorides and cyanide in a 350 kA cell operated for 2396 days was analyzed and the footprint and corrosion mechanism of the harmful substances in SPL were also studied. It is found that the fluorides are mainly concentrated in the cathode carbon block and the layer of dry barrier under the cathodes, which is closely related to permeability of the cathodes and dry barrier the fluorides penetrate in. Cyanide has a low concentration in the cell center and a high concentration in the sidewall, which is positively related to the air amount entering into the areas in the cells.

Thin vanadium pentoxide (V2O5) layers were grown on porous nitrogen-doped-graphene (NG) nanosheets via atomic layer deposition (ALD). The fabricated NG–V2O5 (NG–V) composite electrodes exhibited a good electrochemical performance when used as anodes for lithium-ion batteries (LIBs), which can be attributed to strong chemical bonding between V2O5 and NG substrates and the porous structure of NG, which gives the material an excellent electron- and ion-transport ability. In particular, at a current density of 200 and 1000 mAg−1, the NG–V electrodes showed good capacity retention and high discharge capacities of 608 (after 50 cycles) and 365 mAhg−1 (after 500 cycles), respectively, based on the total electrode.

As an important approach to recover solid waste, the recycling of waste polyester has drawn a growing level of public concern. This study aims to investigate the life cycle assessment and social cost of life cycle assessment of waste polyester recycling. The results show that the polyester recycling process itself has significant environmental impact on global warming, fossil resource scarcity, human carcinogenic toxicity, water consumption and terrestrial ecotoxicity. Global warming, terrestrial ecotoxicity and land use are the most influential categories of social cost of life cycle assessment, with a contribution of 55.7%, 10.9% and 6.3% respectively. Through key process identification, sensitivity analysis and integrated evaluation study, it is found that electricity generation, direct air emissions and transportation are key processes that affect social cost of life cycle assessment and life cycle assessment. The effects of these key processes on social cost of life cycle assessment are greater than that on life cycle assessment. Consequently, the corresponding optimization measures are proposed in order to improve the sustainability performance of polyester industry.

Volatile fatty acids (VFAs) accumulation caused by shock loading severely hampers the performance and stability of anaerobic digestion. An upflow anaerobic sludge blanket (UASB) was operated to examine its performance, sludge properties, and microbial community behavior during shock loading and recovery with exogenous N-hexanoyl-L-homoserine lactone (C

Black aluminum dross (BAD) is a solid hazardous waste produced during the remelting of aluminum alloy scrap and contains a large amount of aluminum and other valuable elements. However, the extraction of its high-value components is challenging because of its complex phase and chemical composition. In this paper, a new process for recovering aluminum and other valuable elements from BAD is reported, which consists of three steps, i.e., catalytic hydrolysis of aluminum nitride, calcination of the obtained aluminum hydroxide, and molten salt electrolysis to prepare aluminum alloy. Under the established optimal conditions for the hydrolysis of aluminum nitride, 4 wt% NaOH, a temperature of 90°C, a liquid-solid ratio of 6 mL g−1, and a reaction time of 3 hours, the recovery rates of nitrogen and chloride salts are 88.8% and 97.57%, respectively. Bayerite and pseudo-boehmite generated by the hydrolysis of aluminum nitride present in BAD were converted into γ-Al2O3 when calcining the material at 800°C for 2 hours resulting in a multi-metal oxide with high alumina content. Aluminum alloy was prepared by electrolysis of the material in the Na3AlF6-AlF3-Al2O3 electrolyte system. This innovative technology can recover 97% of aluminum and other valuable metals (including silicon) in BAD and is a new route to achieve clean and high-value recycling of BAD.

Stress-induced neural injuries are closely linked to the pathogenesis of various neuropsychiatric disorders and psychosomatic diseases. We and others have previously demonstrated certain protective effects of epigallocatechin-3-gallate (EGCG) in stress-induced cerebral impairments, but the underlying protective mechanisms still remain poorly elucidated. Here we provide evidence to support the possible involvement of PKCα and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathways in EGCG-mediated protection against restraint stress-induced neural injuries in rats. In both open-field and step-through behavioral tests, the restraint stress-induced neuronal impairments were significantly ameliorated by administration of EGCG or green tea polyphenols (GTPs), which was associated with a partial restoration of normal plasma glucocorticoid, dopamine and serotonin levels. Furthermore, the stress-induced decrease of PKCα and ERK1/2 expression and phosphorylation was significantly attenuated by EGCG and to a less extent by GTP administration. Additionally, EGCG supplementation restored the production of adenosine triphosphate (ATP) and the expression of a key regulator of cellular energy metabolism, the peroxisome proliferators-activated receptor-γ coactivator-1α (PGC-1α), in stressed animals. In conclusion, PKCα and ERK1/2 signaling pathways as well as PGC-1α-mediated ATP production might be involved in EGCG-mediated protection against stress-induced neural injuries.

Spent potlining (SPL) is generated at the end of the service life of aluminum reduction cells and is a hazardous solid waste that negatively impacts the environment and ecology. Based on the differences in the hazardous and valuable components of SPL, a classified recycling and utilization path is proposed in this work. Three different high-temperature processes of oxygen-controlled treatment, vacuum treatment, and co-processing in a cement kiln were adopted for spent cathode carbon block (SCCB), spent silicon carbide block (SSCB) and spent barrier and insulating refractory materials (SBIM), respectively. After the classified treatments, all the cyanides in SCCB were decomposed, almost all the Si3N4 was decomposed and Na2SiO3 was removed from SSCB, and over 99% of the fluorides was separated from SCCB and SSCB to obtain high graphitization carbon and silicon carbide. The fluorides in SBIM were converted into a mineralizer that lowered the burning temperature of the cement clinker. The performances of prepared cement met the requirements of Portland slag, Portland pozzolana and Portland flash ash cements.

Alkaline wetlands distributed in arid or semi-arid areas are hotspots of methane (CH4) emissions. Periods of drought and flood, although regular, are stressful events encountered by methanogenic anaerobes in alkaline wetlands. To investigate the response of the CH4 cycle of alkaline wetlands to such stresses, we take Zhalong wetland as an example, then determined the CH4 flux and soil microbiomes in the wetland during wet, dry, and flooded periods. The in-situ CH4 flux in the wet period was 9.55–17.29 mg‧m−2‧h−1, but sharply degraded to 3.37–6.61 mg‧m−2‧h−1 in the dry period. It resumed to 4.51–20.80 mg‧m−2‧h−1 when the wetland was flooded again, which indicated that methanogenesis is quite resilient to drought. Syntrophic acetogenesis, and subsequently aceticlastic methanogenesis, were the dominant methanogenic pathways and resisted drought. Members belonging to Syntrophobacterales were the dominant syntrophic acetogens. They enter a viable but non-culturable (VBNC) state to resist drought. The dominant Methanosarcinales have the ability to repair reactive oxygen species damage during dry periods. The community of CH4 sink was governed by anaerobic methanotrophs, which entered a VBNC state or used repair systems to survive dry periods. This study revealed the responses of the CH4 cycle and microbial functional genes to drought and flood in alkaline wetlands.

The spent cathode carbon block (SCCB) from aluminum reduction cells is considered to be a hazardous material due to containing a large amount of soluble fluoride salts and toxic cyanides. The serious environment pollution and ecological destruction will be caused by being openpiled or buried of SCCB. A joint temperature-vacuum controlling process for treating SCCB is proposed in this paper. The thermodynamic analysis by FactSage 7.0, series of experimental investigation, and characteristics tests on the product materials by SEM and XRD were carried out. The factors including temperature, vacuum pressure and retention time that influence the SCCB’s detoxification effects were comprehensively investigated and discussed in detail. It was found out that the soluble fluoride content can be reduced to a level of 3.5 mg·L−1 while cyanide is completely decomposed. A fixed carbon content of 97.89% in the treated materials is obtained under the optimum temperature and vacuum controlling conditions.

This paper adopts a novel data-processing method of ECSA® based on TG/DSC-MS system to basically study the characteristics of release and conversion of fluorides and cyanides during heat treatment of the spent cathode carbon block (SCCB). All the experiments were conducted at 10 K⋅min−1 heating rate and under Ar or Ar–O2 atmospheres. The results indicate that the release of fluorides was just a steady but slow phase transition process under both Ar and Ar–O2 atmospheres, which can be comparatively accelerated when the carbon material was burnt. The cyanides were effectively decomposed at high temperature and at Ar–O2 atmosphere, with around three quarters of the cyanides being converted to the N2 and nearly a quarter being to the NO. Finally, analysis on the flue gas composition indicates that it had a more complicated composition of CO2, N2, NO, NO2, HCN under Ar–O2 atmosphere but only had a composition of CO2 and NO under Ar atmosphere.

To understand the syntrophic mechanism of acetogens and methanogens in anaerobic digestion (AD), functional floras of syntrophic propionate-oxidizing bacteria (SPOB), syntrophic butyrate-oxidizing bacteria (SBOB), aceticlastic methanogens (AM) and hydrogenotrophic methanogens (HM) were separately tested by microbial density to reveal their performance in metabolic activity, extracellular polymeric substances (EPS) production and quorum sensing (QS) signal molecules (acyl homoserine lactones, AHLs) secretion, as well as the regulation of endogenous AHLs in balancing the social behaviors of syntrophic microorganism. The results showed that methanogenesis, EPS production and AHLs secretion of the functional floras were all observably affected by microbial density. The metabolic activity of SBOB, SPOB, AM and HM decreased with a microbial density more than 344, 295, 229 and 237 mgMLVSS/L, respectively. The intraspecific regulation of SPOB and HM were achieved with the mediation of OXOC6-HSL and C10-HSL, respectively. With the mediation of enjoyed signal molecules, metabolic coordination between SPOB and AM was of bidirectional regulation, but it was a unidirectional regulation from HM to SPOB. Syntrophic acetogens and methanogens in AD could bidirectionally regulate their EPS production via QS system to construct syntrophic floras that make the methane fermentation of propionate and butyrate more efficient. The present research work provides a practical strategy to regulate endogenous AHLs by microbial density to enhance the syntrophism of acetogens and methanogens in AD.

An efficient acousto-optic Q-switched Yb-doped Gd3AlxGa5−xO12 (GAGG) (x = 0.5) laser is demonstrated. Under the absorbed pump power of 7.4 W, the maximum average output power of 1.4 W is obtained at the pulse repletion rate of 1 kHz , with the slope efficiency as high as 32%. The pulse width of 40 ns is achieved with the pulse energy and peak power of 1.4 mJ and 35 kW, respectively. What’ more, the output spectrum shows itself tri-wavelength in either CW or Q-switching mode. To our knowledge, this is the first time for realizing simultaneous tri-wavelength Yb:GAGG laser actively Q-switched operation.

The present study examined the hypothesis whether non-target languages are inhibited during multilingual language production by examining the n-2 language repetition cost. In two experiments, Uighur-Chinese-English trilinguals named Arabic digits in one of their three languages according to a visually presented cue. Significant n-2 repetition costs were obtained in both experiments, which indicate that inhibition exists during multilingual word production. In addition, in Experiment 1, it was also found that the n-2 repetition cost was reduced when cues were highly compatible with the task, which means non-target languages are less inhibited. In Experiment 2, the n-2 repetition cost was increased at a shorter CSI. Taken together, these results indicate that inhibition of non-target languages occurs during multilingual language production, and that efficiency of establishing the target language task schema has an effect on the inhibitory control process.

Using the extended tanh-function method (ETM) based on mapping method, the variable separation solutions of the (2 + 1)-dimensional asymmetric Nizhnik–Novikov–Veselov (ANNV) system are derived. By further studying, we find that these variable separation solutions, which seem independent, actually depend on each other. Based on the variable separation solution and by selecting appropriate functions, new types of interactions among semi-foldons and special dromions, peakons, foldons constructed by multi-valued functions are investigated. Moreover, The explicit phase shifts for all the local excitations offered by the quantity U have been given, and are applied to these novel interactions in detail.

By means of the theorem of the vectorial structure of electromagnetic beams and the method of stationary phase, the analytical vectorial structure of cosh-Gaussian (ChG) beam in the far field is presented. The light intensity distributions of a ChG beam and its vectorial structure are investigated in the far field. In addition, the influence of the parameters associated with the cosh term on the light intensity distributions of the whole beam and its structure are also analyzed. The analytical formulae obtained here are applicable not only to the non-paraxial case, but also to the paraxial case. The physical picture of ChG beam in the far field is well depicted from the vectorial structure.

A passively Q-switched all solid-state Nd:LuVO4 1.06 μm laser was demonstrated by using Cr4+:YAG as saturable absorber. The characteristics of average output power, pulse width, repetition rate, pulse energy, and peak power were studied with different output couplings and initial transmission of saturable absorbers. When output coupling with the transmission of 20% was used, the shortest pulse width of 16 ns at the repetition rate of 12.5 kHz was obtained, which results in the pulse energy of 71 μJ and peak power of 4.43 kW with the initial transmission of 70% of Cr4+:YAG crystal.

The description of paraxial Gaussian beam is directly started from the Maxwell’s equations. According to the vector plane wave spectrum representation of Maxwell’s equations and the vectorial structure of electromagnetic beam, the analytical TE and TM terms of paraxial Gaussian beam are presented by means of mathematical techniques in the near field. The influence of linearly polarized angle on the components of the TE and TM terms is investigated. The structural light intensities are depicted in the near field. As the vectorial structures are not orthogonal in the near field, there is a crossed light intensity in the paraxial Gaussian beam. This research reveals the abundant internal structure of paraxial Gaussian beam in the near field.

Large size strontium tungstate (SrWO4) single crystal was grown by Czochralski method. Raman scattering and infrared absorbance spectra measurements show that the characteristic lattice vibrational modes of SrWO4 arise mainly from the internal vibrations of the WO4 tetrahedra and partly by the external SrO8 polyhedra modes. Thermal properties including thermal expansion, specific heat, thermal diffusion and conductivities of the crystal were investigated to evaluate the thermal properties of SrWO4. The anisotropy of thermal properties was explained by crystal structure and its correlation with the lattice vibration spectra.

In this paper, the chiral separation of cefadroxil was studied by capillary electrochromatography. Monolithic capillary column was prepared for the separation of cefadroxil enantiomers. The optimum buffer contained 28.5 mmol/L sodium acetate, 0.95% (v/v) acetic acid, 19 mmol/L beta-cyclodextrin (beta-CD) and 5% (v/v) isopropanol in formamide solution (pH 7.0), with the running voltage of 12 kV, the UV detector wavelength of 254 nm, the sample injected time of 8s and the temperature of 25 degrees C. Under these conditions, the column efficiency of cefadroxil enantiomers were N1=5324 and N2=23,768 with a selectivity factor (alpha) of 1.056 and resolution (Rs) of 0.978. The effect of buffer pH value, beta-CD concentration, organic modifier (isopropanol) concentration and voltage was also investigated for the separation by CEC.

As an important surfactant, Pb surface alloying in surfactant-assisted epitaxy growth was studied by synchrotron radiation photoemission. As annealing causes the submonolayer Pb, distributed as two-dimensional islands on Cu(I 11), to form Pb-Cu surface alloy, Cu growth is also found to activate the Pb-Cu surface alloy formation on submonolayer Pb covered Cu(I 11). Whereas, different from the fact that the Pb-Cu surface alloy is replaced by a Pb over-layer when the Pb coverage increases up to 1.0 ML, Co deposition gives rise to the Pb-Co surface alloy even on the 1.0 ML Pb covered Cu(l 11) surface. In the Pb-Cu surface alloy the Pb 5d core level is shifted toward Fermi level by about 20 meV. Heating de-alloys the Pb-Co surface alloy, while the interface intermixture between Co film and Cu substrate is also enhanced at the same time. (c) 2005 Elsevier B.V. All rights reserved.

Photoemission studies reveal the existences of metallic Rb4C60 and Rb5C60 surface phases on the top layer of C60 single crystal. After Rb3C60 thin film with thickness of nanometers has formed on the (1 1 1) surface layers of the C60 single crystal, the excess deposition of Rb atoms do not induce the bulk-like face-centered cubic to body-centered tetragonal or body-centered cubic structure transitions at room temperature. The large size of C60 molecule offers the surface vacancies for the formation of Rb4C60 and Rb5C60 monolayer that is further verified by Rb 3d core-level photoemission measurements. Valence band photoemission results exhibit the surface phases are metallic.