Pyrrole as a multi-functional additive to concurrently stabilize Zn anode and cathode via interphase regulation towards advanced aqueous zinc-ion battery.

The advancement of aqueous zinc-ion batteries (AZIBs) is impeded by challenges encompassing cathodic and anodic aspects, such as limited capacity and dendrite formation, constraining their broader utilization. Herein, pyrrole, an economically viable and readily accessible compound, is proposed as a versatile electrolyte additive to address these challenges. Experiments and DFT calculations reveal that pyrrole and its derivatives preferentially adsorb onto zinc foil, facilitating the formation of a pyrrole-based solid electrolyte interphase (SEI), which effectively guides uniform Zn2+ deposition through strong attraction force and suppresses hydrogen evolution reactions and parasitic reactions. On the cathode side, the additive promotes the formation of a durable cathode electrolyte interphase (CEI) enriched with poly-pyrrole (Ppy) analogues. Such layer significantly contributes to extra capacity of both polyaniline (PANI) and MnO2 cathodes by leveraging the electrochemical reactivity of Ppy towards Zn2+ and improves their cyclic stability. Consequently, a dendrite-free Zn anode is realized with an extended cyclic lifespan surpassing 6000 h in Zn//Zn cell, coupled with an average Coulombic efficiency of 99.7 % in Cu//Zn cell. Moreover, the PANI//Zn and MnO2//Zn full cells demonstrate enhanced capacities along with improved cycling stability. This work provides a new additive strategy towards concurrent stabilization of cathode and Zn anode in AZIBs.

DIW-Printed Thermal Management PDMS Composites with 3D Structural Thermal Conductive Network of h-BN Platelets and Al2O3 Nanoparticles.

Electronic devices play an increasingly vital role in modern society, and heat accumulation is a major concern during device development, which causes strong market demand for thermal conductivity materials and components. In this paper, a novel thermal conductive material consisting of polydimethylsiloxane (PDMS) and a binary filler system of h-BN platelets and Al2O3 nanoparticles was successfully fabricated using direct ink writing (DIW) 3D printing technology. The addictive manufacturing process not only endows the DIW-printed composites with various geometries but also promotes the construction of a 3D structural thermal conductive network through the shearing force during the printing process. Moreover, the integrity of the thermal conductive network can be optimized by filling the gaps between the BN platelets with Al2O3 particles. Resultingly, the configuration of the binary fillers is arranged by the shearing force during the DIW process, fabricating the thermal conductive network of oriented fillers. The DIW-printed BN/Al2O3/PDMS with 45 wt% thermal conductive binary filler can reach a thermal conductivity of 0.98 W/(m·K), higher than the 0.62 W/(m·K) of the control sample. In this study, a novel strategy for the thermal conductive performance improvement of composites based on DIW technology is successfully verified, paving a new way for thermal management.

Controlling Shear Rate for Designable Thermal Conductivity in Direct Ink Printing of Polydimethylsiloxane/Boron Nitride Composites.

Efficient heat dissipation is vital for advancing device integration and high-frequency performance. Three-dimensional printing, famous for its convenience and structural controllability, facilitates complex parts with high thermal conductivity. Despite this, few studies have considered the influence of shear rate on the thermal conductivity of printed parts. Herein, polydimethylsiloxane/boron nitride (PDMS/BN) composites were prepared and printed by direct ink writing (DIW). In order to ensure the smooth extrusion of the printing process and the structural stability of the part, a system with 40 wt% BN was selected according to the rheological properties. In addition, the effect of printing speed on the morphology of BN particles during 3D printing was studied by XRD, SEM observation, as well as ANSYS Polyflow simulation. The results demonstrated that increasing the printing speed from 10 mm/s to 120 mm/s altered the orientation angle of BN particles from 78.3° to 35.7°, promoting their alignment along the printing direction due to the high shear rate experienced. The resulting printed parts accordingly exhibited an impressive thermal conductivity of 0.849 W∙m-1∙K-1, higher than the 0.454 W∙m-1∙K-1 of the control sample. This study provides valuable insights and an important reference for future developments in the fabrication of thermal management devices with customizable thermal conductivity.

[Effect of insulin on expression of whole-blood platelet membrane P-selectin].

OBJECTIVE: To investigate the effects of insulin on the expression of whole-blood platelet membrane P-selectin. METHODS: Flow cytometry (FCM) was used to detect the expression of whole-blood platelet membrane P-selectin, and the effect of insulin on the expression on quiescent and activated plasma platelet observed in normal young subjects. RESULTS: Insulin had no effect on the P-selectin expression on quiescent platelet membrane, but significantly inhibited the up-regulation of P-selectin expression induced by thrombin and collagen respectively, exhibiting dose- and time-dependent effects. CONCLUSION: Insulin can inhibit P-selectin expression on activated platelet membrane.

[Effect of insulin on the expression of platelet membrane glycoprotein II b/III a and its mechanisms].

OBJECTIVE: To investigate the effects of insulin on the expression of platelet membrane glycoprotein (GP) IIb/III a and its mechanism in normal subjects. METHODS: Flow cytometry was used to detect the expression of the whole-blood platelet membrane GP b/ a. The respective effects of insulin, L-nitro-arginine methyl ester (L-NAME) and methylene blue (MB) and their combination on the expression of GP b/ a were also studied. RESULTS: Insulin had no effect on the expression of GP II b/III a in healthy subjects, but significantly inhibited the up-regulated expression of GP II b/III a induced respectively by thrombin and collagen. The inhibitory effects of insulin on thrombin- or collagen-induced expression of platelet membrane GP II b/III a were dose- and time-dependent, and could be completely blocked by L-NAME or methylene blue. CONCLUSION: Insulin may inhibit the over-expression of platelet membrane GP IIb/III a by NOS-->NO-->GC-->GMP pathway.