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1.
《Ceramics International》2021,47(22):31886-31893
In this contribution, SnFe2O4 nanoparticles were prepared by the solvothermal method, the structural properties were performed using X-Ray Diffraction (DRX) to prove the success of tin ferrite formation and to determine de crystals parameters. The size and morphological study were build using Scanning Electron Microscopy (SEM) and Transmission Electron microscopy (TEM), the results showed that the size of particles is uniform with a range of particles (5–7 nm). The magnetic properties were carried out using the SQUID device, the SnFe2O4 nanoparticles have a magnetic transition at 750 K. In addition, the hysteresis loops at low temperature displayed Ms and Mr equals to 23 emu/g and 6 emu/g, respectively. The magnetoresistance properties were investigated, the SnFe2O4 nanoparticles present a large magnetoresistance effect (80%). The experimental results are supplemented by model calculations utilizing density functional theory and Monte-Carlo simulations. 相似文献
2.
Gang Liu Ya Wang Jianpeng Li Ying Liu Maryam Salehabadi 《Journal of Sulfur Chemistry》2021,42(1):40-50
Based on the experimental reports, Au-decoration on the ZnO nanostructures dramatically increases the electronic sensitivity to H2S gas. In the current study, we computationally scrutinized the mechanism of Au-decoration on a ZnO nanotube (ZON) and the influence on its sensing behavior toward H2S gas. The intrinsic ZON weakly interacted with the H2S gas with an adsorption energy of ?11.2 kcal/mol. The interaction showed no effect on the HOMO–LUMO gap and conductivity of ZON. The predicted response of intrinsic ZON toward H2S gas is 6.3, which increases to 78.1 by the Au-decoration at 298 K. The corresponding experimental values are about 5.0 and 80.0, indicating excellent agreement with our findings. We showed that the Au atom catalyzes the reaction 3O2?+?2H2S?→?2SO2?+?2H2O. Our calculated energy barrier (at 298 K) is about 12.3 kcal/mol for this reaction. The gap and electrical conductance Au-ZON largely changed by this reaction are attributed to the electron donation and back-donation processes. The obtained recovery time is about 1.35 ms for desorption of generated gases from the surface of the Au-ZON sensor. 相似文献
3.
《Current Opinion in Solid State & Materials Science》2022,26(6):101042
Powering wearable bioelectronics with decent skin conformability and wearing comfort is highly desired. Fiber batteries could provide an attractive alternative to traditional rigid ones and present a compelling solution to this problem. In this review, we will discuss the various classes of fiber batteries, including lithium batteries, zinc batteries, and other types of fiber batteries. We will then report the latest research progress on each battery category through its working mechanism, materials usage, structure design, and wearable applications. Finally, we provide insights into current challenges and future applications of fiber batteries, aiming to promote the development of low-cost and high-performance fiber battery technologies for wearable bioelectronics. 相似文献
4.
5.
《International Journal of Hydrogen Energy》2022,47(84):35903-35913
The outstanding physical properties make TM5Si4 silicides become the potential silicon-based transition-metal ultrahigh-temperature materials. In present work, we adopt the first-principles scheme to explore the structural stability, mechanical properties and explain the hydrogenated mechanism of Ti5Si4, Zr5Si4 and Hf5Si4 using the electronic structures. And the investigation increases the theoretical support for the developments and applications of TM5Si4 silicides. Three hydrogenated models have shown that the hydrogen displays the stability for hydrogenated TM5Si4 compounds. Furthermore, the introduction of hydrogen occupation has weakened the elastic properties of TM5Si4. The metallic property of TM5Si4 and three hydrogenated models was confirmed by the electronic structures. The localized hybridization between hydrogen and TM5Si4 confirm the hydrogenated structural stability. 相似文献
6.
《International Journal of Hydrogen Energy》2022,47(64):27608-27616
The vanadium hydrides have better hydrogen storage capacity in comparison to the other metal hydrides. Although the structure of VH2 hydride has been reported, the structural stability, electronic and optical properties of VH2 hydride are unclear. To solve these problems, we apply the first-principles method to study the structural stability, electronic and optical properties of VH2 hydrides. Similar to the metal dihydrides, four possible VH2 hydrides such as the cubic (Fm-3m), tetragonal (I4/mmm), tetragonal (P42/mnm) and orthorhombic (Pnma) are designed. The result shows that the cubic VH2 hydride is a thermodynamic and dynamical stability. In particular, the tetragonal (I4/mmm) and the orthorhombic (Pnma) VH2 hydrides are firstly predicted. It is found that these VH2 hydrides show metallic behavior. The electronic interaction of V (d-state)-H (s-state) is beneficial to improve the hydrogen storage in VH2 hydride. In addition, the formation of V–H bond can improve the structural stability of VH2 hydride. Based on the analysis of optical properties, it is found that all VH2 hydrides show the ultraviolet response. Compared to the tetragonal and orthorhombic VH2 hydrides, the cubic VH2 hydride has better storage optical properties. Therefore, we believe that the VH2 hydride is a promising hydrogen storage material. 相似文献
7.
Hailong Liang Bo Zhang Dayu Zhou Xintai Guo Yan Li Yanqing Lu Yuanyuan Guo 《Ceramics International》2021,47(9):12137-12143
In this work, we introduced a simple solution processing method to prepare yttrium (Y) doped hafnium oxide (HfO2) based dielectric films. The films had high densities, low surface roughness, maximum permittivity of about 32, leakage current < 1.0 × 10?7 A/cm2 at 2 MV/cm, and breakdown field >5.0 MV/cm. In addition to dielectric performance, we investigated the influence of YO1.5 fraction on the electronic structure between Y doped HfO2 thin films and silicon (Si) substrates. The valence band electronic structure, energy gap and conduction band structure changed linearly with YO1.5 fraction. Given this cost-effective deposition technique and excellent dielectric performance, solution-processed Y doped HfO2 based thin films have the potential for insulator applications. 相似文献
8.
Zhao Li Yahong Yuan Tianli Yue Jianghong Meng 《International Journal of Food Science & Technology》2019,54(9):2679-2689
5-HMF (5-hydroxymethyl-furfural) is a product of thermal treatment and is increasingly considered a food contaminant. Here, different concentrations of 5-HMF were measured in apple juice to evaluate the performance of the electronic nose (EN) and electronic tongue (ET) as rapid detection techniques for 5-HMF when coupled with chemometric analysis. Principal component analysis (PCA) and linear discriminant analysis (LDA) evaluated the discrimination capacity of EN and ET for 5-HMF. Loading analysis examined the discrimination contribution of the EN sensors. Partial least square (PLS) regression analysis established a quantitative prediction model for different concentrations of 5-HMF based on EN and ET data set. The optimal models had a coefficient of determination (R2) of 0.926 and a root-mean-square error of prediction (RMSEP) of 0.4168 in EN; there were R2 of 0.914 and RMSEP of 0.5836 in ET. These results demonstrate that EN and ET coupled with chemometric analysis are two promising approaches for the rapid and online detection of 5-HMF in apple juice. 相似文献
9.
Marta Bobiano Nuno Rodrigues Marta Madureira Luís G. Dias Ana C. A. Veloso José A. Pereira António M. Peres 《Journal of the American Oil Chemists' Society》2019,96(7):751-760
Olive oil price and consumers’ preference depend on the commercial grade classification that can decrease if any sensory defect is perceived leading to an economic loss. Enriched oils, obtained by incorporating dried aromatic herbs, spices, or essential oils, which is a common practice in the Mediterranean region, are commercially available. This practice may conceal the fraudulent purpose of masking the perception of sensory defects. The detection of this type of fraud is a difficult task, requiring sensory analysis. Thus, in this study, extra-virgin and lampante olive oils, the latter classification being due to the perception of an intense winey-vinegary defect, were deliberately enriched with different amounts of basil-dried herbs and oregano-dried herbs. Sensory analysis showed that, depending on the aromatic herb and on the added amount (0.011–0.110 g herb per kg oil), the defect intensity could be masked leading to an erroneous classification of flavored lampante oils as flavored virgin oils. In contrast, the electronic tongue-chemometric approach could unmask the defect in flavored oils (predictive sensitivities: 70–78%) and semiquantitatively discriminate flavored oils according to the added levels of basil or oregano (predictive sensitivities: 93–100%). The electronic tongue approach showed satisfactory unmasking performance when compared with the sensory panel, and so, its future application as a quality control taste-sensor device for disclosing olive oil sensory defects masked by the incorporation of flavoring agents may be forseen. 相似文献
10.
文章归纳了2020年电子电路产业一些技术热点,主要有5G电路板设计和基材,制造方面半加成法、3D打印、直接金属化孔电镀和垂直互连结构等技术,以及集成电路封装载板技术。 相似文献