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Due to the low cost, high element abundance and intrinsic safety, potassium-ion batteries (KIBs) have attracted a surge of interest in recent years. Currently, the key challenge and obstacle to the development of KIBs is to find suitable anode materials with large capacity, high rate capability and small lattice changes during the charge/discharge process. MXenes with excellent energy storage properties are promising anode materials for KIBs and their energy performance largely depends on the surface termination. Here, two-dimensional O- and S-terminated V2C MXene anode materials are designed to model high performance potassium-ion batteries. Using first-principles calculations, the structural properties and potential battery performance in KIBs of V2CO2 and V2CS2 are systematically investigated. The inherent metallic nature, a small diffusion barrier, a low average open circuit voltage, and a high theoretical specific capacity (489.93 mA h g-1 of V2CO2 and 200.24 mA h g-1 of V2CS2) demonstrate that both of them are ideal anode materials for KIBs. Meanwhile, we also investigated the mechanism of the difference in energy performance between V2CO2 and V2CS2 at atomic and electronic levels, in other words, the energy performance difference introduced by surface O- and S-terminations.

Microporous silica (MS) materials are a kind of an emerging and promising adsorbent precursor. MS prepared from vermiculite has the advantages of easy preparation, low cost, and low layer charge. In this study, organo-MS (OMS) modified by a typical gemini surfactant 1,2-bis(hexadecyldimethylammonio)ethane dibromide (G16) is first synthesized and proved to have effective retention capacity toward cationic dyes. Fourier transform infrared spectroscopy, TG-DTG, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller are used to explore the structural characters of adsorbents. Gradient adsorption of compound MS (MS and OMS) in a binary dye system [methylene blue (MB) and crystal violet (CV)] was investigated. In a single system, the relationship between the adsorption capacity and influencing factors (dye concentration, contact time, temperature, and pH), adsorption kinetics, isotherms, as well as thermodynamics was comprehensively compared to reveal the adsorption mechanism. The adsorption values of MB and CV on MS and OMS are 308 mg g–1 (R = 77.0%, 15 min) and 250 mg g–1 (R = 83.3%), respectively, which may be caused by various intermolecular interactions (electrostatic or hydrophobic interactions) between the dye and adsorbent surface. In a binary system, the improved first spectroscopy method is used to calculate the individual concentration of the dye in the binary system. The total removal efficiency of gradient adsorption reaches as high as 89.5% (MB) and 86.4% (CV). In addition, compound MS can be effectively regenerated by HCl solution for several cycles.

Hydrogen is regarded to be one of the most promising renewable and clean energy sources. Finding a highly efficient and cost-effective catalyst to generate hydrogen via water splitting has become a research hotspot. Two-dimensional materials with exotic structural and electronic properties have been considered as economical alternatives. In this work, 2D SnSe films with high quality of crystallinity were grown on a mica substrate via molecular beam epitaxy. The electronic property of the prepared SnSe thin films can be easily and accurately tuned in situ by three orders of magnitude through the controllable compensation of Sn atoms. The prepared film normally exhibited p-type conduction due to the deficiency of Sn in the film during its growth. First-principle calculations explained that Sn vacancies can introduce additional reactive sites for the hydrogen evolution reaction (HER) and enhance the HER performance by accelerating electron migration and promoting continuous hydrogen generation, which was mirrored by the reduced Gibbs free energy by a factor of 2.3 as compared with the pure SnSe film. The results pave the way for synthesized 2D SnSe thin films in the applications of hydrogen production.

Many publications have reported that the incidence of atherosclerotic cardiovascular diseases is higher in patients with type 2 diabetes mellitus (T2DM) than in the non-diabetic population; however, until now, the reason has been unclear. In this study, 25 males (25/64, 39.06%) and 19 females (19/54, 35.19%) had complications with atherosclerosis after two years. To reveal the risk factors for developing atherosclerosis in patients with T2DM, plasma fatty acid metabolic profiling based on gas chromatography-mass spectrometry was combined with the analysis of clinical biochemical indices. The results of partial least squares-discriminant and canonical correlation analyses suggested that C20:0, C22:6n-3, glycosylated hemoglobin, waist circumference, and waist-to-hip ratio are likely to be closely related to T2DM complicated with atherosclerosis. Metabolomic information is a beneficial supplement to existing clinical indices and is useful in predicting the development of a patient's disease and optimizing the treatment.

Quorum sensing (QS) mediates the coordination of population-based behavior in bacteria, which is highly involved in the formation of bacterial biofilms and virulence of bacteria in vivo. Therefore, an inhibition of QS and biofilm growth is of therapeutic interest. This study exhibited the an auto-inducer molecule (AI-2) activity as the most important component of the QS system was positively correlated with the growth and biofilm formation of S. epidermidis strains. In addition, TASA and matrine have a capacity to inhibit AI-2 in three S. epidermidis strains compared to the control (p