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Composite materials are prone to delamination defects during the preparation process. For the non-destructive testing and evaluation of carbon fiber reinforced polymer (CFRP) delamination defects, a standard specimen with embedded delamination defects was prepared, and then phased array ultrasonic non-destructive testing technology was used to detect the delamination defects. The qualitative assessment and quantitative evaluation of delamination defects were carried out. First, the delamination defect specimen was prepared with the autoclave forming process, and polyimide films were embedded in the specimen before progress; then, the specimen was inspected using phased array ultrasonic technique, qualitative and quantitative measurement of delamination defects were analyzed with ultrasonic S-scan and C-scan image, uncertainty analysis of test results were also discussed in combination with the sound field simulation. The results show that the shapes of the delamination defects in the sample are regular, the embedment depth and size are consistent with the preset. The index direction size of the delamination defect is more accurate, and the scan direction size is larger than the actual size. Phased array ultrasonic technique can accurately identify the shape, size and position of delamination defects with high detection accuracy and still has good detection effects for small defects.

The dissolution behavior of equilibrium η(MgZn2), T(Al2Mg3Zn3), S(Al2CuMg) and Fe-containing Al7Cu2Fe insoluble phases of hot rolled 7050 aluminum alloy during solid solution treatment was studied. The dissolution kinetics data of the equilibrium phases were obtained by means of in-situ scanning electron microscope tissue detection method. On the basis of bulk diffusion controlled dissolution kinetics models, the effects of curvature and interfacial reaction on atomic migration rate were introduced, and the dissolution kinetics models of η, T and S phases were established. The results show that η and T phases of 7050 aluminum alloy can be completely dissolved within 2 min at the usual solution temperature (470℃); it takes a long time for S phase to completely dissolve, while the Fe-containing phase hardly dissolves; the curvature has little effect on the phase dissolution, but the dissolution rate can be greatly reduced by the interfacial reaction. The predicted results of the second-phase dissolution kinetics models are in good agreement with the measured results, such as η, T and S phase, which can provide guidance for optimizing the solid solution process of Al-Zn-Mg-Cu alloy.

Objective To evaluate clinical effects of of computer aided design and computer aided manufacturing(CAD/CAM) on the ceramic onlay restoration of endodontically treated posterior tooth.Methods 126 endodontically treated posterior teeth were restored with chair-side CAD/CAM ceramic onlays. The patient satisfaction surveys were carried out immediately after restoration. Clinical evaluations, including marginal adaptation, contour apearance, surface texture, color match were made according to the modified United States Public Health Service (USPHS) criteria immediately after the restoration and 1 year follow-up.Results More than 91% patients were satisfied with the restorations. According to USPHS criteria, 92.1％and 91.3%（χ2 = 0.052,P = 0.820） restorations reached A level inmarginal adaptation immediately and in 1 year follow-up, and that was 97.6% for the contour appearance, 95.2% and 93.7%（χ2 = 0.303,P = 0.582） for the surface texture, 80.2% and 81.7%（χ2 = 0.103,P = 0.748） for the color match. Only one ceramic restoration fractured during follow-up. Conclusion CAD/CAM ceramic onlays have good clinical effect in restoration of endodontically treated posterior teeth .

C32H33N11O14, Monoclinic, P21/c a = 12.3339(18) Å, b = 37.764(5) Å, c = 8.2077(12) Å, α = 90°, β = 109.053(2)°, γ = 90°, V = 3613.6(9) Å3, Z = 4, Rgt(F) = 0.0621, wRref(F2) = 0.1574, T = 296(2) K.

Teicoplanin (TCP) is an important lipoglycopeptide antibiotic produced by fermenting Actinoplanes teichomyceticus. The change in TCP concentration is important to measure in the fermentation process. In this study, a reagent-free and rapid quantification method for TCP in the TCP–Tris–HCl mixture samples was developed using near-infrared (NIR) spectroscopy by focusing our attention on the fermentation process for TCP. The absorbance optimization (AO) partial least squares (PLS) was proposed and integrated with the moving window (MW) PLS, which is called AO–MW–PLS method, to select appropriate wavebands. A model set that includes various wavebands that were equivalent to the optimal AO–MW–PLS waveband was proposed based on statistical considerations. The public region of all equivalent wavebands was just one of the equivalent wavebands. The obtained public regions were 1540–1868nm for TCP and 1114–1310nm for Tris. The root-mean-square error and correlation coefficient for leave-one-out cross validation were 0.046mg mL−1 and 0.9998mg mL−1 for TCP, and 0.235mg mL−1 and 0.9986mg mL−1 for Tris, respectively. All the models achieved highly accurate prediction effects, and the selected wavebands provided valuable references for designing specialized spectrometers. This study provided a valuable reference for further application of the proposed methods to TCP fermentation broth and to other spectroscopic analysis fields.

In order to solve the contradiction between large aperture elements and high-resolution images, in this study, we propose an improved image-resolution method based on generative adversarial network (GAN). First, we analyze the imaging principle of the optical synthetic aperture. Further, we improve a super-resolution GAN; especially, this network uses a multi-scale convolutional cascade to obtain global features of the image, and a multi-scale receptive field block and residual in residual dense block are built to obtain image details. In addition, this study uses the Mish function as the activation function of the discriminator to solve the problems of neuron extreme, gradient explosion, and poor generalization ability of the model. Through simulation, the results show that the proposed method can achieve a peak signal-to-noise ratio (PSNR) of 30 dB compared with traditional image super-resolution reconstruction methods for synthetic aperture image. The method proposed has an improvement of 2 dB in the PSNR and 0.016 in structure similarity index measure compared with the original super-resolution GAN. Therefore, this method can effectively reduce the image distortion and improve the quality of image reconstruction.

High-entropy alloy (HEA) coatings have demonstrated great potential in anti-wear applications. To further improve the mechanical and tribo-corrosion properties of the HEA coatings, the VAlTiMoSi, (VAlTiMoSi)80C20, and (VAlTiMoSi)60C40 coatings were successfully deposited by DC magnetron sputtering. The microstructure, mechanical, and tribo-corrosion properties of as-deposited and heat-treated coatings were analyzed. All the as-deposited HEA coatings were BCC + amorphous phases. The thermal effect promoted the formation of intermetallic compounds, and the C inhibited the formation of Mo3Si and Ti5Si4. The hardness and elastic modulus of the heat-treated VAlTiMoSi coating were 20.1 and 294.0 GPa, respectively. The heat-treated (VAlTiMoSi)60C40 coating showed the lowest wear rate, namely 5.2 × 10−14 m3·Nm−1, and the best formation ability of passive film in 3.5 wt% NaCl solution.

To research the paracrine role of adipose tissue-derived mesenchymal stem cells (ADMSCs) in promoting angiogenesis under the three-dimensional culture conditions consisting of a functionalized self-assembling peptide nanofiber hydrogel. ADMSCs were isolated, extracted, and then identified. Three kinds of peptides (RADAI-16, RGD, and KLT) were prepared, and a functionalized self-assembling peptide nanofiber hydrogel was produced by mixing RADAI-16, RGD, and KLT in a volume ratio 2:1:1. AFM was used to observe RADAI-16, RGD, KLT, and the functionalized self-assembling peptide nanofiber hydrogel. Then, ADMSCs were cultured under three-dimensional conditions consisting of the peptide nanofiber hydrogel, and AFM was used to observe cell migration. The ADMSCs in the common culture group (37°C, 5% CO2 cell culture box) and hypoxic culture group (37°C, 10% CO2, and 1% O2 hypoxic culture box) acted as controls. ADMSCs were three-dimensionally cultured in situ for 1 day, and then the concentrations of HGF and VEGF in the supernatant were determined by ELISA. Cells were extracted from the peptide nanofiber hydrogel, and HO-1 expression was detected by western blotting. ADMSCs have high expression levels of CD29, CD90, and CDl05 and low expression levels of CD34 and CD45. In addition, they can differentiate into adipocytes and osteocytes. The diameters of the fibers of RADAI-16, RGD, KLT, and the functionalized self-assembling peptide hydrogel are 17.34 ± 1.82, 15.50 ± 1.41, 13.77 ± 1.18, and 20.26 ± 1.25 nm, respectively. AFM indicated that cells in the functionalized self-assembling peptide nanofiber hydrogel migrated farther than those in RADAI-16. The concentrations of HGF under common, hypoxic, and three-dimensional culture conditions were 47.31 ± 6.75, 247.86 ± 17.59, and 297.25 ± 17.95 pg/mL, respectively, while the concentrations of VEGF were 218.30 ± 3.03, 267.13 ± 4.27, and 289.14 ± 3.11 pg/mL, respectively. Both HGF and VEGF were expressed more in the presence of the functionalized self-assembling peptide nanofiber hydrogel than in its absence (P < 0.05). Using western blotting, ADMSCs cultured under hypoxic and three-dimensional conditions were found to have high expression levels of HO-1. Culturing ADMSCs under three-dimensional conditions consisting of functionalized self-assembling peptide nanofiber hydrogels can promote their paracrine role in angiogenesis, such as HGF and VEGF, and hypoxia is one of the important elements.

In order to understand the corrosion inhibition effect of the reaction products of glucose and glycine (PGG) on carbon steel, the weight loss measurement, electrochemical techniques, and SEM observation were employed to study the corrosion inhibition of PGG on carbon steel in 1 mol/L HCl solution. Results showed that PGG showed good corrosion inhibition effect on carbon steel, and the corrosion inhibition efficiency enhanced with the increase of PGG concentration. When the highest concentration of PGG was 250 mg/L, it showed the best corrosion inhibition effect, the inhibition efficiency reached the maximum of 94.7%, which had the decreasing tendency with increasing corrosion temperature. Moreover, PGG was a mixed type corrosion inhibitor by retarding both cathodic reduction reaction and anodic oxidation reaction process of carbon steel electrode simultaneously. The good corrosion inhibition was mainly due to combination of physical and chemical adsorption of multi phase to form a protective film covering on the surface of carbon steel that isolated the carbon steel from the acid solution and thereby suppressed carbon steel corrosion. PGG adsorption on the carbon steel surface followed the Langmuir adsorption isotherm model. In general, the product of glucose and glycine (PGG) was an excellent corrosion inhibitor for carbon steel in 1 mol/L HCl solution.