[en] Highlights: • The effect of organic solvents on lowering the viscosity was studied at 0.0967 MPa. • Organic solvents of DMA, DMF, DMSO and PYR were investigated. • Negative viscosity deviations are observed in mixtures of organic solvents with IL. - Abstract: Ionic liquids have been widely explored in making biofuels from biomass. Ionic liquid generally has high viscosity that would impede the dissolution of biomass. One of the possible ways is to use the organic solvent to lower the viscosity. In this work, experimental studies on the densities and viscosities of binary mixtures are conducted at atmospheric pressure (0.0967 MPa) in the temperature range from 303.15 K to 353.15 K. The mixtures are comprised by ionic liquid of 1-hexyl-3-methylimidazolium chloride and organic solvents of N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide and pyridine. The excess properties are calculated to evaluate the interactions of ionic liquid with organic solvents. The Vogel-Fulcher-Tammann equation along with ideal Grunberg-Nissan equation is introduced to correlate the viscosity values. The results are used to quantitatively analyze the effects of organic solvents on lowering the viscosities of ionic liquid.

[en] The skeleton assembly platform is the key equipment for the manufacture of nuclear fuel assembly. At present, there is no calibration method related to the skeleton assembly platform at home or abroad. In order to ensure the accurate positioning of the frame and the dimension of the skeleton quality, the calibration method of the skeleton assembly platform is carried out. Calibration methods include calibration items, calibration required standard instruments, calibration methods and feasibility analysis of straightness instead of flatness and so on. After the calibration method is determined, the calibration experiment is carried out according to the calibration method. The calibration results are in accordance with the technical requirements, the evaluation uncertainty is also made to prove the calibration method is workable, and it can be extended to assembly platform, pull rods platform and expansion platform, etc. (authors)

[en] By using 243 event-based precipitation samples from April 2011 to March 2012 and 289 long-term monthly average values from the GNIP stations, this study discussed the contribution rate of recycled moisture in The Yangtze River and The Yellow River in China and its controlling factors. The contribution rate of recycled moisture in The Yellow River is higher than the values in The Yangtze River basin during a whole year. The average proportion of recycled moisture, 5.52%, in the Yellow River basin is greater than the value of 1.97% in the Yangtze River basin in summer monsoon and 4.72% higher than 3.67% in winter monsoon. Distinct moisture sources may be a factor to influence the extent of recycled moisture. The Hybrid Single Particle Lagrangian Integrated Trajectory Model was applied to simulate the moisture sources in the study area. The air mass trajectories were controlled by distinct wind regimes during different time. The fraction of recycled moisture increases when the study region is under the control of the westerly air mass. Moreover, the influence of d-excess values should also be taken into consideration. Sub-cloud evaporation exists in the study area and has an impact on the recycled moisture. The evaporation rate in the Yellow River basin is significantly higher than the proportion in the Yangtze River over a year. It can be found that the study region which has a relatively higher evaporation rate always has a higher proportion in recycled moisture.

[en] Highlights: • TiO_2-coated LTO was in-situ prepared via a microemulsion-assisted hydrothermal route. • Anatase-TiO_2 coating layer enhances the electrochemical performance of Li_4Ti_5O_1_2. • The as-prepared sample presents high-rate capability and cyclic stability. - Abstract: Li_4Ti_5O_1_2 nanorod coated by anatase-TiO_2 is in situ synthesized via a microemulsion-assisted hydrothermal method followed by heat treatment at 550 °C in air. Compared with pure Li_4Ti_5O_1_2, Li_4Ti_5O_1_2 nanorod coated by anatase-TiO_2 presents much improved electrochemical characteristics in terms of high specific capacity, excellent rate capability and cyclic stability (96.0% of initial capacity at a current density of 1.75 A g"−"1 up to 100 cycles). Acting as a perfect nanocoating layer, anatase-TiO_2 contributes some capacity and gives an enhanced performance to the Li_4Ti_5O_1_2 electrode. All the results suggest that Li_4Ti_5O_1_2 nanorod coated by anatase-TiO_2 could be suitable for use as a high-rate anode material for lithium-ion batteries

[en] For a spherical-cap nucleus to become a 'transformation nucleus', the linear dimension (d) of the flat substrate must exceed the critical nucleus size (2r *). This Turnbull criterion (d ≥ 2r *) defines a minimum undercooling for grain formation on, and effective inoculation with, flat nucleating substrates. However, for nucleation on potent substrates the spherical-cap model is no longer tenable. The free growth model has in general considered the growth of a two-dimensional nucleus on a potent flat substrate. Inspired by the particle-core structures observed in magnesium alloys after inoculation with nearly spherical zirconium particles, a model has been proposed, on the basis of an adsorption and surface diffusion mechanism, for heterogeneous nucleation and grain formation on potent spherical substrates of d ≥ 2r *. The critical undercooling required is found to be approximately the same as that defined by Turnbull's patch nucleation theory. The model shows excellent agreement with experiments compared from different perspectives

[en] The polyvinylpyrrolidone (PVP) hybrid luminescent micro-/nanofibers doped with the novel hybrid SiO₂-coated CdTe nanocrystals (HS-CdTe NCs) have been fabricated for the first time via the electrospinning technique. The morphologies and photoluminescence (PL) emissions of HS-CdTe/PVP micro-/nanofibers prepared by doping the HS-CdTe NCs with the different PL peak wavelength (571, 616, and 643 nm) in PVP fibers were investigated by optical and PL microscope. The results revealed that all the HS-CdTe/PVP hybrid fibers showed an ultralong length for several hundreds of micrometers and a relatively uniform diameter of 1000 ∼ 1200 nm. The hybrid fibers displayed a wavelength-tunable PL emission, determining by the PL of doped HS-CdTe NCs. Moreover, similar to the original PL properties of HS-CdTe NCs before the electrospinning, the HS-CdTe/PVP fibers also showed a series of superior PL properties, such as narrow and symmetry PL spectrum, high, and uniform brightness. For comparison purpose, we also prepared three CdTe/PVP hybrid fibers by doping the 553 nm, 600 nm, and 633 nm PL-emitting CdTe NCs respectively in PVP electrospinning fibers. The characterization results showed that, the obtained three CdTe/PVP hybrid fibers had a basically satisfactory micro-/nanofiber morphology with a long length and relatively uniform diameter, but all the fibers exhibited very weak PL emissions. The enormous contrast in PL properties between HS-CdTe/PVP and CdTe/PVP fibers should mainly be ascribed to the different connection modes of ligands with the NCs and the passivation effect of inert hybrid silica shell on HS-CdTe. It is hopeful that the high luminescent HS-CdTe/PVP micro-/nanofibers with the tunable PL peak wavelength would be a good candidate in the optical sensor, light-emitting devices (LEDs), nanometer-scale waveguides, and the other related photonic materials. - Highlights: • The HS-CdTe/PVP electrospun hybrid fibers were fabricated for the first time. • The hybrid fibers displayed a high PL brightness and tunable PL emission. • The hybrid fibers showed an ultralong length for several hundreds of micrometers. • The hybrid fibers had a relatively uniform diameter of 1000 ∼ 1200 nm. • The novel HS-CdTe NCs resulted in the superior PL properties of electrospun fibers

[en] Two types of motional Stark effect (MSE) polarimeters were detected and the pilot experiments of measuring the magnetic pitch angle are carried out in the HL-2A tokamak. The main part of the first type consists of 4 polarizers and a spectrometer, and the accuracy of ±0.15 ° can be obtained. The pitch angles of magnetic field are achieved by 7 spatial channels covering 24 cm major radius with time resolution of 40 ms. The profiles of safety factor are obtained by combining with the equilibrium and reconstruction fitting code (EFIT). The position of q = 1 surface is well consistent with the results measured by soft-X array. The other one based on a dual photo-elastic modulator (PEM) can obtain the accuracy of ±0.15 ° in the calibration experiments. The deviation angle between analyzing polarizer axis and the angular bisector of the dual PEM influences heavily on the linearity and the accuracy of the system. Time resolution of 20 ms was obtained for one channel during the pilot experiments. (authors)

[en] A non-agitation liquid processing approach for the production of semisolid magnesium slurries containing fine and spherical particles has been proposed on the basis of the Mullins-Sekerka stability criterion for spherical growth and recent advances in grain refinement of magnesium. It is shown that semisolid magnesium slurries containing fine and spherical particles are obtainable directly from the liquid state without agitation, via effective control of nucleation and growth by grain refinement with zirconium. The solid fraction can be varied in a wide range up to more than 50%. The formation of spherical primary magnesium particles is attributed to the combined effects of both dissolved and undissolved zirconium, which give rise to a high nucleation rate and a small undercooling when the melt contains a high level of dissolved zirconium and a sufficient number of suitably sized, undissolved zirconium particles. Grain refinement offers a promising non-agitation liquid processing approach for semisolid structure formation

[en] Novel Li_0.9Y_(0.9-x-y)Zr_0.1O₂:Eu_x³⁺, R_y³⁺ (R Ce,Bi) red nanocrystal phosphors were synthesized by the sol-combustion process at 800 deg. C. XRD and TEM were used to evaluate the crystallinity and the morphological characterization of the samples. The photoluminescence properties and lifetime of the obtained phosphor nanoparticles were measured using an Edinburgh FLS920 at room temperature. The result showed that the luminescence intensity of Li_0.9Y_(0.9-x-y)Zr_0.1O₂:Eu_x³⁺ was increased by Bi³⁺ and Ce³⁺ by 900% and 600%, respectively. The emission mechanism and sensitization mechanism of Bi³⁺ and Ce³⁺ on Eu³⁺ emission intensity were described and explained in detail in this work. The high bright and color-uniform fluorescence images of the doped samples with short luminescence decay times (nanosecond level) confirmed the potential applications of the phosphors in light-emitting diodes and display devices

[en] For a long time, the regular, even sinusoidal dynamic load is used to study the development of pore pressure and strain in soil dynamic tests. But in fact, the dynamic loads in the study of soil dynamic characteristics are mostly irregular and even random. At present, the equivalent linear model method is used to calculate the dynamic characteristics of soil under random loads. However, this method does not take into account the plastic deformation of soil which is contrary to the actual deformation of soil. In this paper, the stochastic process theory is introduced into the measurement and analysis of soil dynamic characteristics. The dynamic stress time history, dynamic strain time history and dynamic pore pressure time history are all regarded as random processes. So a cross-correlation function method based on stochastic theory is proposed, and the feasibility of determining the damping ratio of soil by this method is verified by means of experiments and numerical analysis. The results show that the cross-correlation function method can not only solve the damping ratio of soil under periodic load, but also determine the damping ratio of soil under random load. (paper)