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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.