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In this work, experiments and comprehensive insights into the proposed covering liquid method to intensify self-preservation effect for methane (CH4) storage are presented. The CH4 hydrate decomposition percentage was 17.6% with the pressure of 0.61 MPa after 12 h at 266.0 K without a covering liquid, which can be reduced to 12.4%, 13.8%, 13.0%, and 8.3% with the pressure of 0.26 MPa, 0.33 MPa, 0.51 MPa, and 0.37 MPa by covering with tetrahydrofuran (THF), cyclopentane (CP), cyclohexane, and n-tetradecane, respectively. When the temperature for CH4 hydrate decomposition was 274.2 K, covering with THF, CP, cyclohexane, and n-tetradecane failed to inhibit CH4 hydrate decomposition. The results suggested that the covering liquid may form a new solid layer (a hydrate layer or other solidified layer) around the CH4 hydrate, which inhibit CH4 transfer below the freezing point of water. However, the new solid layer cannot resist the fast transfer of CH4 from decomposed CH4 hydrate above the freezing point of water. The same phenomenon was also observed in a sodium dodecyl sulfonate (SDS)-dry solution CH4 hydrate formation system. Therefore, the covering method can only intensify the self-preservation effect below the freezing point of water, but cannot generate a self-preservation effect.

Herein, [As2IIIAsVMo8VIV4IVO40]2[CuICu2II(pz)4]2·9H2O/polyaniline/reduced graphene oxide (pz = pyrazine, abbreviated to As3Mo8V4/PANi/rGO) composite is first assembled, characterized and systematically explored for its supercapacitor performance. As3Mo8V4/PANi/rGO composite shows a exceptional specific capacitance (2351 F g−1 at 1 A g−1) and outstanding cyclic stability (96.9% after 5000 cycles). The symmetric supercapacitor exhibits high specific capacitance of 1295 F g−1 at 1 A g−1 and excellent energy density of 88.1 Wh kg-1 at power density of 349.6 W kg-1, while maintaining a notable capacitance retention of 85.7% after 5000 cycles at 2 A g-1. The above results confirm the potential application of As3Mo8V4/PANi/rGO composite in energy storage devices.

In this study, D201 resin-hydrated iron oxide (HFO) nanocomposites were prepared for the first time for Cr(VI) removal in a high-gravity rotating packed bed (RPB), and then D201-HFO nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The results show that HFO nanoparticles embedded in D201 resin exhibit an average particle size of 10.34 nm, a narrow particle size distribution and excellent dispersibility. The use of 0.05 g of D201-HFO nanocomposite prepared in the RPB (D201-HFO-R) leads to efficient removal of Cr(VI) from 10 mg/L to below 50 ppb, and it has a higher reaction rate constant (k = 0.959 h−1) than that prepared in a stirred tank reactor (STR). D201-HFO-R nanocomposites also exhibit higher competitive adsorption of Cr(VI) against CO32–, NO3– and SO42−. Notably, it still shows good removal efficiency for Cr(VI) after five adsorption-regeneration cycles. The removal mechanism of Cr(VI) by D201-HFO-R mainly involves complexation and electrostatic attraction. This study provides a simple and facile method to prepare D201-HFO nanocomposites in the RPB for wastewater treatment.

This study identified the volatile beany flavor compounds and determined the microstructures, expansion rates, and secondary protein structures of different textured soybean proteins. The effect of energy input on the textured protein structure and the relationship between the protein structure and the beany flavor were elucidated. The results showed that the textured soybean proteins exhibited excellent porosity and hydrophobicity at a specific mechanical energy of 609 kJ/kg and a texturization temperature of 155 °C. Structural characterization showed that the textured soybean proteins formed large, uniform, dense air chamber cavity structures. Low α-helix and β-sheet content decreased the tightness of the protein. The evaporation of volatile beany flavor compounds with the moisture from the air chamber cavities was inhibited by the binding between the protein and beany flavor substances. The findings of this study provided new insight into volatile beany flavor modulation to improve the sensory quality of textured soybean proteins.

This paper aims to investigate the capacity utilization (CU) of selected large Chinese iron and steel enterprises by using the data envelopment analysis (DEA) approach. In this paper, we first propose a DEA model with an unrestricted capacity directional output distance function by incorporating two joint cost disposability relations and differentiating between non-emission-causing inputs and emission-causing inputs. Second, we define the status of decision-making units (DMUs) with excess capacity and design a method to identify insufficient variable inputs. We use a group of 48 largest Chinese iron and steel enterprises as our sample to investigate their performance in terms of CU indicator. The main findings are summarised and can be used to support the corresponding policymaking for the managers of both government and enterprises.