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Three-dimensional MRI has been increasingly incorporated into various clinical applications, as it provided better through-plane spatial resolution which potentially enhanced the ability to detect more-subtle abnormalities, and provides much more valuable information for clinical usage. However, one major drawback of 3D MRI is the long data-acquisition time and high computational cost. In this review article, we attempted to summarize the most recent development of accelerated 3D MR techniques, from MR signal excitation and encoding to the advancement of reconstruction algorithms and potential applications, by going through over 200 extraordinary researches conducted during the past 20 years. As the field is fast-growing, we hope this survey may serve as a map to understand the current state of the field.

Flexible three-dimensional interconnected carbon nanotubes on the carbon cloth (3D-CNTs/CC) were obtained through simple magnesium reduction reactions. According to the Nernst equation, the cell voltage based on these pure carbon electrodes without any additives could reach 1.5 V due to the higher di-hydrogen evolution over potential in neutral 3.5 M LiCl electrolytes. In order to improve the electrochemical performance of the electrodes, 3D-CNTs/CC electrodes covered with polyaniline barrier layer (3D-PANI/CNTs/CC) were prepared by in situ electropolymerization using interfacial engineering method. The assembled symmetric supercapacitors display a broadened voltage of 1.8 V, high areal capacitance of 380 mF cm−2, outstanding areal energy density of 85.5 μWh cm−2 and 84% of its initial capacitance after 20 000 charge-discharge cycles. This work demonstrated that the interface engineering strategy provides a promising way to improve the energy density of carbon-based aqueous supercapacitors by widening the voltage and boosting the capacitance simultaneously.

Comparing with fused silica fiber, chalcogenide glass fibers are considered as an ideal platform for mid-infrared supercontinuum generation (SCG) because of its higher nonlinear coefficient and wider transparency window. Multimode fiber provides a new way to achieve special spectral characteristics in SCG by introducing intermodal interaction. We investigate the intermodal nonlinear phenomena associated with SCG in multimode chalcogenide fiber by numerically solving multimode generalized nonlinear Schrödinger equation. The results indicate that when the phase matching condition is satisfied, the intermodal interaction leads to the generation of dispersive waves at mid-infrared wavelength. Furthermore, intermodal and intramodal soliton collision are observed, and the bandwidth of the supercontinuum is increased by the intermodal interaction. These results may provide a new way for the generation of mid-infrared supercontinuum light source.

When gas insulated metal enclosed switchgear and controlgear (GIS) has internal discharge, some faults are difficult to find during inspections due to the enclosed metal casing. This paper introduces the event of the floating potential discharge inside the GIS equipment of a 500kV substation found by GIS on-line monitoring system. Through on-site ultra-high frequency detection and precise positioning of the oscilloscope to determine the position of the discharge source at a certain switch, combined with the disassembly of the equipment, it is determined that the equipment defect is the discharge of the floating electrode of the switch fork.The results show that the on-line monitoring of GIS partial discharge has an important reference role in discovering the internal discharge of equipment during the test interval, and the monitoring and maintenance of GIS partial discharge on-line monitoring system should be strengthened in daily work.

Intercultural communication ability is an important factor in learning a foreign language, which can help us to have better daily communication. Therefore, to improve the intercultural communication ability of Japanese majors has become a hot topic of social concern, which is in urgent need of the reform of the current teaching mode in Universities. Through various ways, such as refined classroom teaching, extracurricular practice, micro class, MOOC class, etc., students can better understand Japanese culture, which will improve their intercultural communication ability. In computer-assisted Japanese teaching in colleges and universities, language teaching and cultural teaching are two independent systems, which have not been well integrated. Therefore, universities must improve the cross-cultural communication ability of Japanese students, which will meet the needs of the society for diversified and Applied Japanese talents[1-2]. First of all, this paper puts forward the focus of intercultural communication in Japanese teaching. Then, this paper puts forward some questions. Finally, some suggestions are put forward[3-4].

Colleges and universities are the cradle of talent training in China, which undertakes the responsibility of exporting professional talents to the society. With the increase of economic and trade between China and Japan, colleges and universities should strengthen the Japanese teaching, which will better provide applied professional Japanese talents. Japanese is becoming popular, popular and folk, which has become a tool for international communication. However, there are still many problems in Japanese Teaching in Colleges and universities in China, which requires colleges and universities to constantly improve their teaching ability. By optimizing teachers and teaching content with the computer aid, colleges and universities can improve their Japanese teaching. First of all, this paper analyzes the current situation of Japanese teaching from three aspects: teaching materials, teachers and students[1]. Then, this paper puts forward some questions. Finally, some suggestions are put forward[2].

Processable aqueous dispersions of two-dimensional (2D) transition metal dichalcogenides (TMDs) nanosheets show extraordinary promise in assembling laminar films for a variety of applications but are usually limited by the oxidation of adsorbed water molecular on the edge and defect regions, which damage the stability of the colloidal solution and electric properties of the resulted films. In this work, we developed a pre-protection strategy by adding ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) as the protective agent into TiS2 nanosheets aqueous dispersions. The introduction of EDTA-2Na can effectively slow down the adsorption and decomposition of confined water molecules and enhance the oxidation resistance of TiS2 nanosheets in the colloidal solution. Compared with the untreated TiS2 nanosheets, the storage time of the pre-protected nanosheets in aqueous dispersions can be significantly improved, and the electrical conductivity of prepared laminar films as thermoelectric materials also increased from 2.43 × 103 S m−1 to 1.51 × 104 S m−1. Our exploration provides a new concept performed in aqueous solution for the protection of TMDs nanosheets, which can be adopted to fabricate TMDs films with stable electric properties by controlling the assembly process of colloidal chemistry

A kind of nanoemulsion nickel catalyst was prepared for the application of coliquefaction of lignite and heavy residue. The particle size and microstructures of dispersed phases in emulsion and the sulfurized product were characterized by dynamic light scattering and transmission electron microscope. Catalytic performances of prepared catalysts at different dosage were investigated and the microscopic features of solid residues with catalyst or not were compared. Experimental results showed the optimization mixing speed for emulsion nickel catalyst preparation was 2000 r/min, with an average diameter of 180 nm, and the active phases of prepared catalyst after sulfurization was Ni3S2. The emulsion nickel catalyst displayed a favorable catalytic activity, with a coal conversion efficiency of 93.7 % and an oil yield of 72.33 wt%. The fragmented shapes and lowed diameters of solid residue with prepared catalyst relative to no catalyst further displayed its significant roles in the inhibition of condensation reaction and coke formation.

Mg–1Zn–1Mn (wt%) alloy and Mg–1Zn–1Mn–xSr (wt%, x = 0.1, 0.25, 0.5, 1) alloy as candidates for degradable biomaterials were prepared by casting and extrusion methods. The effect of Sr addition on microstructure, mechanical properties, corrosion resistance and cytotoxicity of Mg–Zn–Mn alloy was investigated. The results showed that Mg–1Zn–1Mn alloy mainly consisted of α-Mg matrix phase while Mg11Zn4Sr3 phase was formed in Mg–1Zn–1Mn–0.25Sr, Mg–1Zn–1Mn–0.5Sr and Mg–1Zn–1Mn–1Sr alloy. After adding Sr, the highest tensile strength of Mg–1Zn–1Mn–1Sr alloy was 280 MPa, but its elongation dropped to 7%. Mg–1Zn–1Mn–0.25Sr alloy exhibited better corrosion resistance in immersion tests, with hydrogen evolution rate of 0.42 mm/year, weight loss rate of 0.72 mm/year, and pH value of 9.0. The cytotoxicity tests indicated that both Mg–1Zn–1Mn and Mg–1Zn–1Mn–0.25Sr alloys were non-toxic against L-929 cells and the highest relative growth rate of Mg–Zn–Mn–0.25Sr extracts group was 102%.

Metasurfaces have attracted significant attention due to the control of the electromagnetic waves that they enable. In this paper, we demonstrate a high-transmission gradient phase discontinuity metasurface composed of metallic rods and cylindrical dielectric resonators operating at a broadband microwave frequency from 8 GHz to 9.8 GHz, with a fractional bandwidth of 20.2%. The proposed gradient phase discontinuity metasurface can achieve complete 2π transmission phase coverage with π/4 phase intervals by varying the geometric parameters of the dielectric resonators and metallic rods. It is shown that the proposed metasurface can refract a normally incident plane wave to an angle of 30°. The broadband metasurface is flexible, and the refracted angle can be adjusted easily by varying the lattice constant. Besides the broadband anomalous refraction, we also demonstrate the metasurface can produce an interesting vortex and wave-focusing in the wide frequency range from 8 GHz to 9.8 GHz. Finally, we demonstrate that the present metasurface can tailor interference wavefronts to plane wavefronts.

Nowadays, inorganic/polymer composites have attracted significant interest in thermoelectric field, since the composite materials usually achieve their respective advantages complementary to each other. In this work, molybdenum diselenide (MoSe2) was synthesized by a facile hydrothermal method. Solution processible two-dimensional (2D) MoSe2 nanosheets (NSs) were successfully obtained using dimethylsulfoxide (DMSO) solvent or lithium intercalation procedure. Combined with Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), MoSe2/PEDOT:PSS composite thin films were fabricated by direct vacuum-filtration method. Thermoelectric properties of composite thin films were investigated systematically and found that 2D MoSe2 NSs and PEDOT:PSS have the synergistic effect on improving thermoelectric properties. The maximum power factor was calculated to be 48.6 µW m−1 K−2 with 5 wt% 2D MoSe2 NSs embedding into PEDOT:PSS matrix, which is almost 69% higher than that of pure PEDOT:PSS. These results demonstrate that 2D inorganic/polymer composite method is one of promising strategies to get high-performance polymer-based thermoelectric composites.

The wet-chemical approach is of great significance for the synthesis of two-dimensional (2D) bismuth telluride nanoplatelets as a potential thermoelectric (TE) material. Herein, we proposed a simple and effective solution method with the assistance of aniline for the fabrication of bismuth telluride nanoplatelets at a low temperature of 100 °C. The choice of aniline with its dual function avoided the simultaneous use of a capping regent and a toxic reductant. The as-synthesized nanoplatelets have a large size of more than 900 × 500 nm2 and a small thickness of 15.4 nm. The growth of bismuth telluride nanoplatelets are related to the Bi/Te ratio of precursors indicating that a larger content of the Bi precursor is more conducive to the formation of 2D nanoplatelets. The bismuth telluride nanoplatelets pressed into a pellet show a smaller electrical resistivity (∼6.5 × 10-3 Ω · m) and a larger Seebeck coefficient (-135 μV K-1), as well as a lower thermal conductivity (0.27 W m-1 K-1) than those of nanoparticles. The next goal is to further reduce the electrical resistivity and optimize the TE performance by disposing of the residual reactant of aniline adsorbed on the surface of the nanoplatelets.