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1.
Cobalt oxide (Co3O4) modified anatase titanium dioxide nanotubes (ATNTs) have been investigated for the electrochemical sensing of hydrogen peroxide (H2O2). ATNTs have been synthesized by a two-step anodization process. ATNTs were then modified with Co3O4 employing chemical bath deposition method. The structure and morphology of ATNTs and their modification with Co3O4 has been confirmed by X-ray diffraction by scanning electron microscopy. H2O2 sensing has been studied in 0.1 M PBS solution, by cyclic voltammetry and amperometry. Variation in the peak positions and current densities was observed with addition of H2O2 for Co3O4 modified ATNTs. Sensitivity and limit of detection improved with modification of ATNTs with Co3O4 with precursor concentration up to 0.8 M. However, at higher precursor concentrations sensitivity and limit of detection toward H2O2 deteriorated. Co3O4 Modified ATNTS using 0.8 M precursor concentration are comparatively more suitable for H2O2 sensing applications due to the optimum formation of Co3O4/ATNTs heterojunctions. 相似文献
2.
In this paper, we study the well-posedness and the asymptotic stability of a one-dimensional thermoelastic microbeam system, where the heat conduction is given by Gurtin-Pipkin thermal law. We first establish the well-posedness of the system by using the semigroup arguments and Lumer-Phillips theorem. We then obtain an explicit and general formula for the energy decay rates through perturbed energy method and some properties of the convex functions. 相似文献
3.
In this paper we investigated the stability of fractional order fuzzy cellular neural networks with leakage delay and time varying delays. Based on Lyapunov theory and applying bounded techniques of fractional calculation, sufficient criterion are established to guarantee the stability. Hybrid feedback control is applied to derive the proposed results. Finally, numerical examples with simulation results are given to illustrate the effectiveness of the proposed method. 相似文献
4.
5.
The localized electrostatic structures with dissipation due to ion-neutral collisions in a symmetric warm pair-ion plasma in the presence of non-Maxwellian population of electrons are studied. The analytical model for ion dynamics is based on fluid equations and the evolution equation is derived by using the reductive perturbation scheme in the form of a damped Korteweg-de Vries equation. The parameter regime relevant to space-based observations and laboratory plasmas is considered and time evolution of the propagating ion-acoustic soliton is discussed. The energetic-particles-driven properties of soliton for various spectral indices, dissipation, ion temperature, and density are illustrated with comparison to the thermal mode for Boltzmann distribution of electrons. 相似文献
6.
《中国化学快报》2022,33(4):1889-1894
Permeation enhancers (PEs), such as N-[8-(2-hydroxybenzoyl)amino]-caprylate (SNAC), have been reported to improve the oral absorption of various macromolecules. However, the bioavailabilities of these formulations are quite low and variable due to the influences of enzymes, pH and other gastrointestinal barriers. In this study, we revealed that SNAC could interact with insulin to form tight complexes in a specific concentration (insulin ≥ 40 µg/mL)-, ratio (SNAC/insulin ≥ 20:1)- and pH (≥ 6.8)-dependent manner, thus contributing to a significantly high efficacy of oral insulin delivery. Specifically, absorption mechanism studies revealed that the SNAC/insulin complexes were internalized into the cells by passive diffusion and remained intact when transported in the cytosol. Furthermore, the complexes accelerated the exocytosis of insulin to the basolateral side, thereby enhancing its intestinal mucosal permeability. Eudragit? S100-entrapped SNAC/insulin microspheres were then prepared and exhibited an apparent permeability coefficient (Papp) that was 6.6-fold higher than that of the insulin solution. In diabetic rats, hypoglycemic activity was sustained for more than 10 h after the microspheres were loaded into enteric-coated capsules. Further pharmacokinetic studies revealed an approximately 6.3% oral bioavailability in both the fasted and fed states, indicating a negligible food effect. Collectively, this study provides insight into the interaction between PEs and payloads and presents an SNAC-based oral insulin delivery system that has high oral bioavailability and patient-friendly medication guidance. 相似文献
7.
High pressure can effectively control the phase transition of MoTe2 in experiment, but the mechanism is still unclear. In this work, we show by first-principles calculations that the phase transition is suppressed and phase becomes more stable under high pressure, which originates from the pressure-induced change of the interlayer band occupancies near the Fermi energy. Specifically, the interlayer states of phase tend to be fully occupied under high pressure, while they keep partially occupied for the phase. The increase of the band occupancies makes the phase more favorable in energy and prevents the structure changing from to phase. Moreover, we also analyze the superconductivity under high pressure based on BCS theory by calculating the density of states and phonon spectra. Our results may shed some light on understanding the relationship between the interlayer band occupancy and crystal stability of MoTe2 under high pressures. 相似文献
8.
Wu Fang Guo Xiaoxue Hao Gazi Hu Yubing Jiang Wei 《Journal of Solid State Electrochemistry》2019,23(9):2627-2637
Journal of Solid State Electrochemistry - Developing low-cost and earth-abundant electrocatalysts with high activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER)... 相似文献
9.
Yong-Li Li Qiang Zhang Jian-Jun Wu Li-Jun Xue Li-Ming Chen Jun-Mian Tian Zhuo-Ni Xu Ying Chen Xian-Wen Yang Xiao-Jiang Hao Jie Li 《Tetrahedron letters》2019,60(10):751-753
From Abies nukiangensis, two novel 13,14-seco-abietane diterpenes, nukiangendines A (1) and B (2) were isolated. Their relative structures were determined by extensive NMR and HRMS spectroscopic analysis. The absolute configuration of 1 was established by ECD calculations. Compound 1 showed significant anti-hepatitis C virus (HCV) effects. 相似文献
10.
Nonlinear Dynamics - In this paper, we mainly propose a chaotic secure communication scheme which is based on the synchronization of double-layered and multiple complex dynamical networks. Compared... 相似文献