No abstract

By optimizing the main materials in lithium‐air batteries, namely sulfolane as electrolyte solvent, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as electrolyte salt, carbon paper as current collector, and Li2O2–C hybrids as positive electrode materials, a performance of 800 cycles with a specific capacity of 1000 mAh g−1 (based on the total mass of positive electrode materials) and an average energy efficiency of 74.72% has been achieved in this work and for the first time reported in the field of lithium‐air battery. Sulfolane‐based electrolyte and carbon paper current collector play the most critical role in building such a lithium‐air battery of high cycle life. The findings described here are expected to benefit the pursuit of green, sustainable, and high‐performance lithium‐air batteries.

By definition, normal healthy volunteers are assumed not to react to a TV/PC screen provocation. To our great surprise, this proved not to be true. The present results might lay a foundation to understand the underlying cause of so-called "screen dermatitis" with special reference to mast cells. However, blind or double-blind experiments using patients ought to be further investigated in order to find out the exact cause for the observed changes. Such causes include the effects of surrounding airborne chemicals, stress factors, etc.

No abstract

Combing Cu and Ag in alloy state holds promise to serve as tandem catalyst for electrocatalytic CO2 reduction but is restricted by immiscibility in the bulk. Here, a far-from-equilibrium method...

This study reports a facile approach to construct versatile zein-polydopamine-casein core–shell nanocomposites (ZPCs) for polyphenol delivery systems. The surface of zein particles was first modified with mussel-inspired polydopamine (PDA), and then coated with casein, forming stable colloidal particles against environmental stresses including pH, salinity, storage, redispersion, and UV irradiation. Compared with free resveratrol (RES), the encapsulation of RES into ZPCs (RES-ZPCs) enhanced approximately 5-fold and 2.5-fold antioxidant activity for DPPH and ABTS assays, respectively. Cellular H2O2 scavenging assay of RES-ZPCs presents 100% exogenous reactive oxygen species elimination, whereas free RES eliminates only 63.5%. In vitro cell uptake and cytotoxicity assays show that ZPCs could be uptake and exhibits nontoxic on the cell proliferation. This concept of combining PDA and polyphenols with antioxidant activity and stability may provide new insights into designing highly active, stable polyphenol delivery systems and holds promise for applications in food, dietary supplement, and pharmaceutical industries.

No abstract

Monolayer MoS 2 as a member of two-dimensional transition metal dichalcogenides (TMDs) has attracted considerable attention due to its superior optoelectronic properties. Understanding the photocarrier dynamics and transport in these two dimensional systems is beneficial for applications from photovoltaics to sensing. However, various structural defects strongly impact the dynamics and transport of photocarriers. Especially there lacks a precise measuring and understanding of photocarrier transport in TMDs. Here, femtosecond transient absorption spectroscopy and microscopy were employed to study the photocarrier dynamics and transport in monolayer MoS 2 . Defect correlated photocarrier dynamics are observed across the monolayer MoS 2 where exciton formation and nonradiative recombination are the two dominant decay processes. To the best of our knowledge, we report two distinct photocarrier transport regimes in MoS 2 for the first time with diffusion coefficients of =  D 8.5 0.4 fast cm 2 s −1 and =  D 1.3 0.6 slow cm 2 s −1 , by taking advantages of ultrafast microscopy with ∼20 nm spatial precision and ∼200 fs temporal resolution. These two regimes are ascribed to fast hot photocarrier diffusion and slow phonon-limited thermal diffusion, respectively. The results indicate that the initial fast photocarrier transport is less dependent on structural defects compared to photocarrier relaxation dynamics which may be useful for hot photocarrier extraction applications.