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The frequency splitting of the two modes is proportional to the strain measured by X-ray diffraction and its magnitude agrees with first-principles calculations. The results offer a fast, nondestructive, and precise method for measuring both in- and out-of-plane strain in ceria and can be readily applied to other ionic conductors.The application of conductive hydrogels in intelligent biomimetic electronics is a hot topic in recent years, but it is still a great challenge to develop the conductive hydrogels through a rapid fabrication process at ambient temperature. In this work, a versatile poly(acrylamide) @cellulose nanocrystal/tannic acid-silver nanocomposite (NC) hydrogel integrated with excellent stretchability, repeatable self-adhesion, high strain sensitivity, and antibacterial property, was synthesized via radical polymerization within 30 s at ambient temperature. Notably, this rapid polymerization was realized through a tannic acid-silver (TA-Ag) mediated dynamic catalysis system that was capable of activating ammonium persulfate and then initiated the free-radical polymerization of the acrylamide monomer. Benefiting from the incorporation of TA-Ag metal ion nanocomplexes and cellulose nanocrystals, which acted as dynamic connecting bridges by hydrogen bonds to efficiently dissipate energy, the obtained NC hydrogels exhibited prominent tensile strain (up to 4000%), flexibility, self-recovery, and antifatigue properties. In addition, the hydrogels showed repeatable adhesiveness to different substrates (e.g., glass, wood, bone, metal, and skin) and significant antibacterial properties, which were merits for the hydrogels to be assembled into a flexible epidermal sensor for long-term human-machine interfacial contact without concerns about the use of external adhesive tapes and bacterial breeding. Moreover, the remarkable conductivity (σ ∼ 5.6 ms cm-1) and strain sensitivity (gauge factor = 1.02) allowed the flexible epidermal sensors to monitor various human motions in real time, including huge movement of deformations (e.g., wrist, elbow, neck, shoulder) and subtle motions. It is envisioned that this work would provide a promising strategy for the rapid preparation of conductive hydrogels in the application of flexible electronic skin, biomedical devices, and soft robotics.The sesquiterpene cyclase epi-isozizaene synthase (EIZS) catalyzes the cyclization of farnesyl diphosphate to form the tricyclic precursor of the antibiotic albaflavenone. The hydrophobic active site is largely defined by aromatic residues that direct a multistep reaction sequence through multiple carbocation intermediates. The previous substitution of polar residues for a key aromatic residue, F96, converts EIZS into a high-fidelity sesquisabinene synthase the F96S, F96M, and F96Q variants generate 78%, 91%, and 97% sesquisabinene A, respectively. Here, we report high-resolution X-ray crystal structures of two of these reprogrammed cyclases. The structures of the F96M EIZS-Mg2+3-risedronate and F96M EIZS-Mg2+3-inorganic pyrophosphate-benzyltriethylammonium cation complexes reveal structural changes in the F96 aromatic cluster that redirect the cyclization pathway leading from the bisabolyl carbocation intermediate in catalysis. The structure of the F96S EIZS-Mg2+3-neridronate complex reveals a partially occupied inhibitor and an enzyme active site caught in transition between open and closed states. Finally, three structures of wild-type EIZS complexed with the bisphosphonate inhibitors neridronate, pamidronate, and risedronate provide a foundation for understanding binding differences between wild-type and variant enzymes. These structures provide new insight regarding active site flexibility, particularly with regard to the potential for subtle expansion and contraction to accommodate ligands of varying sizes as well as bound water molecules. Additionally, these structures highlight the importance of conformational changes in the F96 aromatic cluster that could influence cation-π interactions with carbocation intermediates in catalysis.The one-dimensional (1D) ABX3-type perovskite [(CH3)3PCH2F]CdCl2Br (1) has been obtained on the basis of the design of an organic-inorganic hybrid. Strikingly, it experiences sequential phase transitions at around 295 and 336 K, respectively. Given the noticeable steplike dielectric anomalies in the vicinity of 295 K, 1 is identified as a promising dielectric-switchable material. According to the single-crystal structure analysis, the order-to-disorder transformation of the [(CH3)3PCH2F]+ cation is the main reason for the phase transitions and the change of space group from the orthorhombic Pnma (No. 62) to the hexagonal P63/m (No. 176). This design of a perovskite structure will inspire more advances in the ever-growing field of switchable functional materials.Uncontrollable dendrite growth and low Coulombic efficiency are the two main obstacles that hinder the application of rechargeable Li metal batteries. Here, an optimized amount of potassium hexafluorophosphate (KPF6, 0.01 M) has been added into the 2 M LiTFSI/ether-based electrolyte to improve the cycling stability of lithium-sulfur (Li-S) batteries. Due to the synergistic effect of self-healing electrostatic shield effect from K+ cations and the LiF-rich solid electrolyte interphases derived from PF6- anions, the KPF6 additive enables a high Li Coulombic efficiency of 98.8% (1 mA cm-2 of 1 mAh cm-2). The symmetrical Li cell can achieve a stable cycling performance for over 200 cycles under a high Li utilization up to 33.3%. Meanwhile, the polysulfide shuttle has been restrained due to the higher concentration of the LiTFSI in the electrolyte. As a result, the assembled Li-S full cell displays excellent capacity retention with only 0.25% decay per cycle in the final electrolyte. Our work offers a smart approach to improve both the anode and cathode performance by the electrolyte modification of rechargeable Li-S batteries.Graphene bubbles (GBs) are of significant interest owing to their distinguished electrical, optical, and magnetic properties. GBs can also serve as high-pressure reaction vessels to numerous chemical reactions. However, previous strategies to produce GBs are relatively elaborate and random. click here Therefore, their potential applications are severely restricted. Here, a facile and effective protocol is proposed to construct position-controllable GBs in liquid nitrogen (LN) with the assistance of laser and graphene wrinkles. Specifically, a film of graphene mounted on a SiO2 substrate (G@SiO2) is subjected to irradiation by a low-power laser in LN and then many GBs emerge from the surface of G@SiO2. Most impressively, the domain where GBs arise is the position of the laser beam spot. Hence, we demonstrated that the high collimation of laser facilitates the position definition of GBs. The microscopic results indicate that some GBs split into three parts when they were subjected to irradiation by an electron. Meanwhile, some GBs degenerate into pores with a diameter of 500 nm when they are exposed to air.

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