Effects of stray AC on corrosion of 3-layer polyethylene coated X70 pipeline steel and cathodic delamination of coating with defects in 3.5 wt-% NaCl solution

In this work, the effects of stray alternating current (AC) on the corrosion of coated X70 pipeline steel and the delamination of 3-layer polyethylene (3PE) coatings with defects were investigated using COMSOL Multiphysics simulation, electrochemical impedance spectroscopy and three-dimensional (3D) digital microscope techniques. The results showed that under the same level of AC interference, pits with deeper maximum pit depth were observed at the smaller defect areas than those at larger defect areas. It was consistent with the simulation results that a greater corrosion current density was accompanied on samples with smaller defects. According to 3D digital images, the larger delamination of 3PE coatings was found on samples with smaller defects. With the increase of current density, the impedance of samples with small defects decreased, while that of samples with large defects increased. Additionally, with the same defect size, the maximum pit depth became deeper and the corrosion was more severe.     

Sol-gel processed high-k aluminum oxide dielectric films for fully solution-processed low-voltage thin-film transistors

High-k oxide dielectric films have attracted intense interest for thin-film transistors (TFTs). However, high-quality oxide dielectrics were traditionally prepared by vacuum routes. Here, amorphous high-k alumina (Al₂O₃) thin films were prepared by the simple sol-gel spin-coating and post-annealing process. The microstructure and dielectric properties of Al₂O₃ dielectric films were systematically investigated. All the Al₂O₃ thin films annealed at 300–600?°C are in amorphous state with ultrasmooth surface (RMS ~ 0.2?nm) and high transparency (above 95%) in the visible range. The leakage current of Al₂O₃ films gradually decreases with the increase of annealing temperature. Al₂O₃ thin films annealed at 600?°C showed the low leakage current density down to 3.9?×?10^?7 A/cm² at 3?MV/cm. With the increase of annealing temperature, the capacitance first decreases then increases to 101.1?nF/cm² (at 600?°C). The obtained k values of Al₂O₃ films are up to 8.2. The achieved dielectric properties of Al₂O₃ thin films are highly comparable with that by vapor and solution methods. Moreover, the fully solution-processed InZnO TFTs with Al₂O₃ dielectric layer exhibit high mobility of 7.23?cm² V^?1 s^?1 at the low operating voltage of 3?V, which is much superior to that on SiO₂ dielectrics with mobility of 1.22?cm²/V^?1 s^?1 at the operating voltage of 40?V. These results demonstrate that solution-processed Al₂O₃ thin films are promising for low-power and high-performance oxide devices.     

环保法规对船舶涂料企业的冲击及应对措施的探讨

随着我国环境保护法规《大气污染防治法》的修订和《涂料征收消费税通知》的公布,探讨了其对船舶涂料企业的冲击及其应对措施。     

Assessment of critical buckling load of functionally graded plates using artificial neural network modeling

Neural Computing and Applications - Predicting the critical buckling loads of functionally graded material (FGM) plates using an analytical method requires solving complex equations with various...     

Face-Specific Data Augmentation for Unconstrained Face Recognition

International Journal of Computer Vision - We identify two issues as key to developing effective face recognition systems: maximizing the appearance variations of training images and minimizing...     

Fabrication and Thermal Dissipation Properties of Carbon Nanofibers Derived from Electrospun Poly(Amic Acid) Carboxylate Salt Nanofibers

Polyimides (PIs) possess excellent mechanical properties, thermal stability, and chemical resistance and can be converted to carbon materials by thermal carbonization. The preparation of carbon nanomaterials by carbonizing PI‐based nanomaterials, however, has been less studied. In this work, the fabrication of PI nanofibers is investigated using electrospinning and their transformation to carbon nanofibers. Poly(amic acid) carboxylate salts (PAASs) solutions are first electrospun to form PAAS nanofibers. After the imidization and carbonization processes, PI and carbon nanofibers can then be obtained, respectively. The Raman spectra reveal that the carbon nanofibers are partially graphitized by the carbonization process. The diameters of the PI nanofibers are observed to be smaller than those of the PAAS nanofibers because of the formation of the more densely packed structures after the imidization processes; the diameters of the carbon nanofibers remain similar to those of the PI nanofibers after the carbonization process. The thermal dissipation behaviors of the PI and carbon nanofibers are also examined. The infrared images indicate that the transfer rates of thermal energy for the carbon nanofibers are higher than those for the PI nanofibers, due to the better thermal conductivity of carbon caused by the covalent sp² bonding between carbon atoms.     

Diagnostic Potential of Differentially Expressed Homer1, IL-1β, and TNF-α in Coronary Artery Disease

Increasing evidences suggest that inflammation plays an important role in the pathogenesis of coronary artery disease (CAD). Numerous inflammatory cytokines and related genes mediate adverse cardiovascular events in patients with CAD, such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and Homer in the present study. The study was carried out on 163 CAD patients at different stages and 68 controls. The gene expression of Homer1, Homer2, Homer3, IL-1β, and TNF-α in the peripheral blood leukocytes were measured by real-time polymerase chain reaction. The mRNA levels of Homer1, IL-1β, and TNF-α in CAD patients were significantly higher than those in the control group, but not Homer2 and Homer3. However, there was no considerable difference in the mRNA levels of Homer1, IL-1β, and TNF-α among AMI, UAP, and SAP three subgroups of CAD. The receiver operating characteristic (ROC) curves showed that Homer1 had a better diagnostic value for UAP patients compared with IL-1β and TNF-α. Like IL-1β and TNF-α, Homer1 may also be an important participant of atherosclerotic plaque development and eventually rupture. The results of the present study may provide an important basis for diagnosing CAD patients, and provide new therapeutic targets for CAD.