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Thermal analysis techniques are increasingly widely used in the fields of minerals, metals, petroleum, food, medicine, chemical industry and other materials related fields. Due to the many influencing factors of thermal analysis technology, there is no unified standard material to calibrate the instrument, which makes it difficult for the laboratory to establish the traceability mechanism of measurement results, so that the accuracy of the results can not be grasped. Through inter-laboratory comparison, the detection ability of the laboratory can be effectively determined to ensure the accuracy of the experimental data. In this paper, the implementation of the interlaboratory comparison project of the Chinese Academy of Sciences 'Determination of the thermal decomposition percentage of unknown substances by thermogravimetric method' is taken as an example. By analyzing the statistical results of the comparison data, it is found that the comparison results are in good agreement, and the deviation of the measurement results of each reference laboratory is within the acceptable range, which verifies the applicability and reliability of the inter-laboratory comparison method in thermal analysis techniques. [ABSTRACT FROM AUTHOR]

Flat-top Sun shield is a part of the disturbance reducing system on the space-based gravitational wave detector TianQin. The Sun shield is expected to guards temperature stability of the satellite's top deck from the low-frequency solar flux fluctuation. This paper introduces an analytic method to study the Sun shield's temperature response to sinusoidal variations of incoming heat flux. Oscillation mode of temperature field is described in the form of wave equation, which satisfies globally the thermal diffusion equation. The continuity equation is solved to reveal the wave behaviours when crossing different media. Three typical boundary conditions are studied in order to solve the wave equation. By applying the method to the TianQin's thermal model, the low-frequency temperature response of the Sun shield and the top deck are derived. The results suggest adopting insulation materials with low thermal diffusivity in the thermal design to shield the solar disturbances. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is a promising electrode material for reversible lithium storage. However, the poor electronic conductivity, sluggish diffusivity, and intrinsic kinetics limit hinder its fast lithium storage capability. Here we present that the oxygen‐deficient TiO2 hierarchical spheres can address the issues for high capacity, long‐term lithium‐ion battery anode. First‐principles calculations show that introducing oxygen vacancies to anatase TiO2 can reduce the bandgap, thus improving the electronic conductivity and further the lithium storage properties of TiO2. By annealing TiO2/H2Ti5O11⋅3H2O hierarchical spheres precursor in nitrogen, accompanying with the phase transfer process, the growth of TiO2 crystallites is restricted due to the generation of residual carbon species, resulting in a well maintained hierarchical spherical structure. Rich oxygen vacancies are generated in the oxygen‐deficient environment and evidenced by EPR, XPS, and UV‐Vis spectra, which enable the TiO2 hierarchical spheres reduced bandgap. The oxygen vacancies in the as‐obtained TiO2 hierarchical spheres together with the high structural integrity of the hierarchical spheres gives rise to superior lithium storage properties including a high specific capacity of 282 mAh g−1 at 200 mA g−1, and long‐term cycling stability with a capacity retention of 85.2 % at 4 A g−1 over 10000 cycles. [ABSTRACT FROM AUTHOR]

SnS 2 /reduced graphite oxide (rGO) composite materials show great potential as high-performance anode candidates in sodium-ion batteries (SIBs) owing to their high specific capacities and power densities. However, the repeated formation/decomposition of the solid electrolyte interface (SEI) layer around composite anodes usually consumes additional sodium cations, resulting in poor Coulombic efficiency and decreasing specific capacity upon cycling. Therefore, in order to compensate for the large irreversible sodium loss of the SnS 2 /rGO anode, this study has proposed a facile strategy by implementing organic solutions of sodium-biphenyl/tetrahydrofuran (Na-Bp/THF) and sodium-naphthylamine/dimethoxyethane (Na-Naph/DME) as chemical presodiation reagents. Particularly, the storage stability of Na-Bp/THF and Na-Naph/DME in ambient air accompanied by their presodiation behavior on the SnS 2 /rGO anode has been investigated, and both reagents exhibited desirable ambient air-tolerant storage stability with favorable sodium supplement effects even after 20 days of storage. More importantly, the initial Coulombic efficiency (ICE) of SnS 2 /rGO electrodes could be controllably increased by immersing in a presodiation reagent for different durations. Consequently, with a facile chemical presodiation strategy of immersion in Na-Bp/THF solution for only 3 min in ambient air, the presodiated SnS 2 /rGO anode has exhibited an outstanding electrochemical performance with a high ICE of 95.6% as well as an ultrahigh specific capacity of 879.2 mAh g -1 after 300 cycles (83.5% of its initial capacity), highly superior to the pristine SnS 2 /rGO anode. This efficient and scalable presodiation strategy provides a new avenue for the prevailing application of other anode candidates in high-energy SIBs.

The development of high-efficiency, robust, and available electrode materials for oxygen evolution reaction (OER) and lithium-ion batteries (LIBs) is critical for clean and sustainable energy system but remains challenging. Herein, a unique yolk-shell structure of Fe 2 O 3 nanotube@hollow Co 9 S 8 nanocage@C is rationally prepared. In a prearranged sequence, the fabrication of Fe 2 O 3 nanotubes is followed by coating of zeolitic imidazolate framework (ZIF-67) layer, chemical etching of ZIF-67 by thioacetamide, and eventual annealing treatment. Benefiting from the hollow structures of Fe 2 O 3 nanotubes and Co 9 S 8 nanocages, the conductivity of carbon coating and the synergy effects between different components, the titled sample possesses abundant accessible active sites, favorable electron transfer rate, and exceptional reaction kinetics in the electrocatalysis. As a result, excellent electrocatalytic activity for alkaline OER is achieved, which delivers a low overpotential of 205 mV at the current density of 10 mA cm -2 along with the Tafel slope of 55 mV dec -1 . Moreover, this material exhibits excellent high-rate capability and excellent cycle life when employed as anode material of LIBs. This work provides a novel approach for the design and the construction of multifunctional electrode materials for energy conversion and storage., (© 2021 The Authors. Small published by Wiley-VCH GmbH.)