[en] With the increasing pressure of energy shortage and the environment pollution, it’s important to take the advantage of the renewable clean energy for newpower generation technology. Solar energy, as a kind of energy with a wide range of sources, has become a new type of clean energy with the most potential for development. This study introduces the project test and progress of solar gas turbine combined generation technology at home and abroad as well as the research status of key technologies. The key technologies of heat collection, heat storage and heat recovery are analyzed and summarized, it has been pointed out that the concentrator ratio achieved by the dish and tower is more than an order of magnitude higher than that of the linear Fresnel and slot; Thermochemical heat storage technology has the theoretical maximum energy storage density, the heat storage of chemical bonds is about 5 times of latent heat, 10 times of sensible heat, and has the advantages of stable chemical bonds, small energy loss and other advantages, energy storage in the future has more development advantages. At the same time, the future research direction of solar thermal power generation technology is prospected. (paper)

[en] Wire position monitor (WPM) is designed to monitor contraction of the cold masses during the cooling-down operation in an accelerator driven system. Because of material difference, machining error, assembly error, etc., each WPM has to be calibrated. The sensing voltage and wire position are of a nonlinear relationship, which is expressed by high order polynomial. Root mean square (RMS) of the polynomial fitting error were 3.8 μm and 7.4 μm at x and y directions, respectively. The alignment test was carried out on the beta cryostat. Optical instruments were used to verify the WPM measuring results. The differences between WPM measuring results and optical measurements were 0.044 and 0.05 mm in x and y direction, respectively. A significant asymmetric contraction was detected, and asymmetry of material was taken as the main reason through analysis. (authors)

[en] Eccentricity is defined as deviation from the circular path and it occurs due to clamping deviation or geometric imperfection when machining elements revolves around the line parallel to the machining element axis, but not around the machining element axis. In this paper, the variation of offset values along the central axial line of different small sections of spindle, tool holder and milling cutter was explored. This work was undertaken by the observation that eccentricity implies adverse impact on the material properties, tooling properties, machining elements, machine system etc. The problem solution was found out by measuring the whole body of spindle, tool holder and milling cutter with Swiss Dial Gauge after dividing them into small sections along the z level axis. After measurement, analysis was done of the recorded data on software’s by illustrating their actual profiles and variation along the Centre line of small divided sections at different orientations. After analysis, we might get the eccentricity of one part with different offsets in z level through offsets in x and y directions and profiles of elements exhibiting less offset values. This work can find its importance in various industries where milling machines are used for machining jet parts, automobile parts and many other etc. (paper)

[en] Arrays of vertically aligned, [010] oriented α-MoO₃ nanorods were grown on planar silicon substrates by pulsed electron beam deposition. The morphology and structure of the nanorods as well as their growth mechanism were investigated. These [010] oriented nanorods exhibited a good field emission performance with a turn-on field of 3.6 V/μm. As the space between layers of the [010] oriented nanorods is large, their formation may be also meaningful for exploring the gas sensing and energy storage properties of layered oxides like α-MoO₃.

[en] The discovery of an extraordinarily superconductive large energy gap in SrTiO_3 supported single-layer FeSe films has recently initiated a great deal of research interests in surface-enhanced superconductivity and superconductive ultrathin films fabricated on crystal surfaces. On account of the instability of ultra-thin films in air, it is desirable to perform electrical transport measurement in ultra-high vaccum (UHV). Here we review the experimental techniques of in situ electrical transport measurement and their applications on superconductive ultrathin films. (topical review)

[en] Background: The Daya Bay neutrino experiment is designed to measure the mixing angle θ_1_3 using anti-neutrinos produced by the reactors of the Daya Bay Nuclear Power Plant (NPP) and the Ling Ao NPP. The distance from nuclear reactors to experiment detectors is needed. Purpose: The aim is to introduce the way of building and measuring the control network during the distance surveying. Methods: The 3D distance was obtained by GPS, total station and laser tracker, and several software and different instruments were used for the combination of data adjustment and coordinate transformation, as well as the correctness checking. Results: Through the actual measurement and data processing, the accuracy of the distance is better than the designed requirement of ±40 mm. Conclusion: The success of the Daya Bay reactor neutrino experiment demonstrates that the result of 3D distance measurement is reasonable and correct, and the survey work makes an important contribution to the Daya Bay reactor neutrino experiment. (authors)

[en] Highlights: • Effect of pH values on the morphologies of Mo₂C. • The morphologies of Mo₂C influenced by Mo sources and C sources. • Control the HER activity by adjusting the morphologies of Mo₂C. -- Abstract: The rational design of highly active electrocatalysts for hydrogen evolution reaction (HER) with controllable morphology creates new opportunities for future hydrogen economy. Herein, a facile strategy was developed to synthesize molybdenum carbide (Mo₂C). First, Mo-based inorganic-organic complexes with distinct architectures were constructed by judiciously adjusting the pH values of the reaction systems as well as the types of inorganic and organic components. Next, the complexes were calcinated under vacuum to form different assemblies such as nanofibers, polyhedrons and microspheres composed of Mo₂C particles. The results indicate that the nanofibers not only alleviate the aggregation and oxidation of internal carbides to achieve more active sites, but also provide a resistance-less path to facilitate the charge transfer process. Consequently, the resultant catalyst with unique one-dimensional (1D) structure exhibits enhanced HER performance under acidic conditions, affording an overpotential of 159 mV at a current density of 10 mA cm⁻² and Tafel slope of 65.2 mV dec⁻¹. This work may provide a new approach to develop Mo-based catalysts with excellent HER activity through morphological control.

[en] Background: In order to explore the sequence of neutrino mass and carry out other advanced scientific researches, Jiangmen underground neutrino observatory is proposed and the project is in the process of site searching. Purpose: This paper mainly introduces the way of position measurement between Jiangmen experimental station and reactor cores of Yangjiang nuclear power plant and Taishan nuclear power plant. Methods: The control network is established and measured by GPS, LGO and the self-developed software is used for data processing and fitting translation. Results: Through the actual measurement, the accuracy of the final coordinate is ±70 mm, which meets the tolerance requirement. Conclusion: According to the feedback from the designer, the scheme of the position measurement is reasonable and feasible. (authors)

[en] In order to examine the potential application of non-stoichiometric molybdenum oxide as anode materials for aqueous micro-supercapacitors, conductive MoO_x films (2 ⩽ x  ⩽  2.3) deposited via RF magnetron sputtering at different temperatures were systematically studied for composition, structure and electrochemical properties in an aqueous solution of Li_2SO_4. The MoO_x (x ≈ 2.3) film deposited at 150 °C exhibited a higher areal capacitance (31 mF cm"−"2 measured at 5 mV s"−"1), best rate capability and excellent stability at potentials below −0.1 V versus saturated calomel electrode, compared to the films deposited at room temperature and at higher temperatures. These superior properties were attributed to the multi-valence composition and mixed-phase microstructure, i.e., the coexistence of MoO_2 nanocrystals and amorphous MoO_x (2.3 < x  ⩽  3). A mechanism combining Mo(IV) oxidation/reduction on the hydrated MoO_2 grain surfaces and cation intercalation/extrusion is proposed to illustrate the pseudo-capacitive process. (paper)

[en] Amorphous Si_xC_1-x films possess the potential to improve wear performance in humid atmospheres and at higher temperatures. But some experimental work on the films showed that silicon contents greatly influenced their microstructures and mechanical properties. Therefore, simulations of molecular dynamics were carried out to predict structures of the Si_xC_1-x films at different silicon contents. The results show that the sp³/sp² ratio of all the films increases, but the stiffness of the films is decreasing with an increase in silicon contents. Moreover, silicon atoms are almost surrounded by carbon atoms, which is in agreement with the experiments.