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Water pollutants existing in their oxyanion forms have high solubility and environmental mobility. To capture these anionic pollutants, cost-effective inorganic materials with cationic frameworks and outstanding removal performance are ideal adsorbents. Herein, we report that two-dimensional (2D) cationic aluminoborate BAC(10) sets a new paradigm for highly selective and efficient capture of Cr(VI) and other oxyanions from aqueous solution. The structure of Cr(VI)-exchanged BAC(10) sample (Cr(VI)@BAC(10), H

Solid-state lithium (Li)–air batteries are recognized as a next-generation solution for energy storage to address the safety and electrochemical stability issues that are encountered in liquid battery systems1–4. However, conventional solid electrolytes are unsuitable for use in solid-state Li–air systems owing to their instability towards lithium metal and/or air, as well as the difficulty in constructing low-resistance interfaces5. Here we present an integrated solid-state Li–air battery that contains an ultrathin, high-ion-conductive lithium-ion-exchanged zeolite X (LiX) membrane as the sole solid electrolyte. This electrolyte is integrated with cast lithium as the anode and carbon nanotubes as the cathode using an in situ assembly strategy. Owing to the intrinsic chemical stability of the zeolite, degeneration of the electrolyte from the effects of lithium or air is effectively suppressed. The battery has a capacity of 12,020 milliamp hours per gram of carbon nanotubes, and has a cycle life of 149 cycles at a current density of 500 milliamps per gram and at a capacity of 1,000 milliamp hours per gram. This cycle life is greater than those of batteries based on lithium aluminium germanium phosphate (12 cycles) and organic electrolytes (102 cycles) under the same conditions. The electrochemical performance, flexibility and stability of zeolite-based Li–air batteries confer practical applicability that could extend to other energy-storage systems, such as Li–ion, Na–air and Na–ion batteries. Flexible, stable and energy-dense solid-state Li–air batteries are realised using ultrathin, chemically inert ion-conductive zeolite membranes as a solid electrolyte.

A liquid chromatography−mass spectrometry method was developed for the simultaneous quantitation of (2R,3R)-Dihydromyricetin and Myricetin in rat plasma samples to facilitate analysis of samples collected after administration of SenDeng-4 medicine. The plasma was subjected to protein precipitation with HCl (containing 10% ascorbic acid) and analyzed using electrospray ionization mass spectrometry in selected ion monitoring mode with Paeoniflorin as an internal standard. Good linearity for the two compounds was observed. The intra- and inter-day precision of analysis was

Functional nanoporous materials are widely explored for CO2 separation, in particular, small-pore aluminosilicate zeolites having a “trapdoor” effect. Such an effect allows the specific adsorbate to push away the sited cations inside the window followed by exclusive admission to the zeolite pores, which is more advantageous for highly selective CO2 separation. Herein, we demonstrated that the protonated organic structure-directing agent in the small-pore silicoaluminophosphate (SAPO) RHO zeolite can be directly exchanged with Na+, K+, or Cs+ and that the Na+ form of SAPO-RHO exhibited unprecedented separation for CO2/CH4, superior to all of the nanoporous materials reported to date. Rietveld refinement revealed that Na+ is sited in the center of the single eight-membered ring (s8r), while K+ and Cs+ are sited in the center of the double 8-rings (d8rs). Theoretical calculations showed that the interaction between Na+ and the s8r in SAPO-RHO was stronger than that in aluminosilicate RHO, giving an enhanced “trapdoor” effect and record high selectivity for CO2 with the separation factor of 2196 for CO2/CH4 (0.02/0.98 bar). The separation factor of Na-SAPO-RHO for CO2/N2 was 196, which was the top level among zeolitic materials. This work opens a new avenue for gas separation by using diverse silicoaluminophosphate zeolites in terms of the cation-tailored “trapdoor” effect., The sodium form of silicoaluminophosphate RHO zeolite exhibits a pronounced cation-tailored “trapdoor” effect, showing an unprecedented selectivity adsorption separation performance for CO2/CH4 and CO2/N2.

How surface wettability affects boiling heat transfer is still a challenging problem at nanoscale. In this work, a three-dimensional analysis of surface potential energy is used to address its relationship to surface wettability and nanoscale pool boiling characteristics of liquid molecules. It is found that the major reason for the enhanced heat transfer by increasing the surface wettability is essentially the improvement of surface potential energy, of which the influence is summarized using logic order. Moreover, the nanoscale boiling of water on copper surfaces with various wettability is investigated, which reveals that the increase in surface wettability can improve the heat transfer coefficient and critical heat flux under high superheat conditions in both nano- and macroscale systems. Besides, the effects of surface potential energy on contact angle, Kapitza resistance, heat transfer coefficient, and critical heat flux are analyzed systematically to demonstrate their relationships. A nondimensional analysis is finally implemented to correlate the normalized surface potential energy (P), the Nusselt number (Nu), and the normalized critical heat flux (J): Nu = 0.081P0.34, J = 0.827P0.50 (P 2.387). This work provides insights into the enhancement mechanisms for the phase-change heat transfer of liquid molecules over surfaces with different wettability.

Nanostructure can apparently affect explosive boiling through surface roughness that functions as a cavity for activating the bubble nucleus. In this work, the effect of surface roughness on the explosive boiling of water film over the copper surfaces with nanochannels having different heights and spacing is investigated. It is found that the increase in the roughness ratio by raising the channel height can substantially promote the onset time of boiling, increase the temperature and heat flux of water, and reduce the interfacial thermal resistance. The increase in roughness ratio by reducing the channel spacing has a promotion effect first and then a weakening effect on the boiling heat transfer. A critical channel spacing is proposed to address this effect on boiling heat transfer on surfaces with increasing roughness ratio by reducing the channel spacing. Moreover, a two-dimensional surface potential energy is used to address the relationship among the roughness ratio, interaction potential energy, and explosive boiling characteristics of the liquid molecules on the structured surfaces. The absolute value of surface potential energy increases with increasing roughness ratio with an increase average rate of 7.1 eV. It is concluded that, when the channel spacing exceeds the critical value, the major reason for the enhanced heat transfer by increasing the roughness ratio is essentially the improvement of the surface potential energy by increasing the heat transfer area. Further investigations on nanochannels with different heights and spacing indicate that the critical channel spacing of 1.444 nm is also suitable for more nanochannel surfaces. The findings of this study can help for a better understanding of the mechanisms of explosive boiling of various fluids on nanostructured surfaces by the surface potential energy.

The boiling of liquid water on the superalloy surface is important in applications such as steam and gas turbines, for which it is necessary to explore the mechanisms of the Leidenfrost phenomenon. The molecular dynamics simulation method provides an effective way to study this phenomenon at the nanoscale. Previous studies, however, have not revealed the Leidenfrost effect of liquid molecules on a superalloy surface. This work investigated the effects of surface temperature and impact velocity on the nanoscale Leidenfrost phenomenon of water droplet over the Fe-Cr superalloy plate. When the surface temperature is higher than 798 K, the Leidenfrost phenomenon occurs on the superalloy surface with apparent temperature, stress, and pressure differences. The results indicate that the Leidenfrost phenomenon is related to the high surface temperature, rather than its impacting velocity. Furthermore, it is found that the Leidenfrost phenomenon is the combined results from the temperature and pressure differences exist in the vapor film, as enough kinetic energy can be generated by the thermal motion to cause the bounce phenomenon of droplet. The revealed mechanisms are critical for the design of a gas turbine, in which vapor film could be dominant in determining the film cooling effectiveness of gas/vapor on the blade surface.

This work investigated the effect of liquid film thickness and surface roughness ratio on the rapid boiling of water over the copper plates in terms of hydraulic diameter defined based on the overall cross-sectional area available for the flow of water film. It is found that the reduction of the hydraulic diameter by increasing the surface roughness ratio can substantially promote the performance of rapid boiling, because of the increase in heat transfer area, together with a decrease in the Kapitza resistance. As a combined effect of the film thickness and the Wenzel roughness ratio, the hydraulic diameter can determine the onset time of boiling and the equilibrium temperature, while it can also determine the heat transfer rate and the Kapitza resistance if the film thickness or the surface roughness is fixed. The effects of the hydraulic diameter on the performances of nanoscale boiling can be applied for heat transfer enhancement and process intensification over any structure in phase-change devices and chemical equipments.

Surface temperature and wettability can synergistically affect the performance of explosive boiling which is important for many industrial processes. This work investigated the explosive boiling of water film over copper surfaces with different wettability under various surface temperature conditions. The results show that the water molecules on the hydrophilic surfaces have higher temperature gradient and initial heat flux, shorter onset time of boiling, and lower Kapitza resistance than those on the hydrophobic surface. Meanwhile, the temperature gradient, the heat flux in the water films, and the onset time of explosive boiling are promoted by elevating the surface temperature. These indicate that the hydrophilic surface under high surface temperature conditions is most favorable for enhancing the explosive boiling heat transfer. Analysis of the onset of boiling reveals that the effect of wettability on the explosive boiling is more prominent under low surface temperatures but is limited under high surface temperatures. This work provides insights into the mechanisms of liquid molecules behaviors on plate surfaces with different wettability and surface temperatures for phase-change heat transfer enhancement and process intensification.