Technical Analysis and Identification of a Glass Inlaid Sui-Tang Dynasty Woman’s Crown

A woman’s crown made of fine gilt bronze with refined glass inlay work was excavated in 2007 from the Sui-Tang tomb called Kunlun M2 in Xi’an. Many questions surround this mysterious crown which was found buried without context. This study uses nondestructive analysis of the crown to determine its significance, when was it made, and the status of the woman for whom was it made. Optical microscopy (OM), optical coherence tomography (OCT), micro X-ray fluorescence imagery (XRF), and Raman spectroscopy were applied, and identified the crown’s inlays as potash-lime glass, composed mainly of the raw materials include vein quartz or quartzite with potassium nitrate as flux. The inlays were sintered before embedding into gilt copper wire filigree. Compared with existing research on other crowns and their inlays, it is speculated that the crown dates from the Sui dynasty (581-618) or early Tang dynasty (618-649), was made locally by Chinese craftsmen and belonged to the wife of an official.

Structural study of single Shockley stacking faults terminated near substrate/epilayer interface in 4H-SiC

Structural analysis is carried out of a single Shockley stacking fault (1SSF) that terminates near the substrate/epilayer interface and originally expanded from a basal plane dislocation segment near the epilayer surface of 4H-SiC. The characteristic zigzag structure is found for the partial dislocations (PDs), with microscopic connecting angles of almost 120°. It has been suggested that the microscopic construction of PDs might be limited by the Peierls valley. The termination line near the substrate/epilayer interface was found to have 30° Si-core and 90° Si-core PDs. This combination is the same as that found near the surface of the epilayer in commonly observed 1SSFs. Penetrating BPDs of this kind were also found experimentally for the first time. For the currently proposed charts for the 1SSF expansions, photoluminescence imaging during UV illumination is one of the nondestructive analysis methods that can provide the structural information and expected expansion shapes of the 1SSFs.

Nondestructive Analysis of Internal Quality in Pears with a Self-Made Near-Infrared Spectrum Detector Combined with Multivariate Data Processing

The consumption of pears has increased, thanks not only to their delicious and juicy flavor, but also their rich nutritional value. Traditional methods of detecting internal qualities (e.g., soluble solid content (SSC), titratable acidity (TA), and taste index (TI)) of pears are reliable, but they are destructive, time-consuming, and polluting. It is necessary to detect internal qualities of pears rapidly and nondestructively by using near-infrared (NIR) spectroscopy. In this study, we used a self-made NIR spectrum detector with an improved variable selection algorithm, named the variable stability and cluster analysis algorithm (VSCAA), to establish a partial least squares regression (PLSR) model to detect SSC content in snow pears. VSCAA is a variable selection method based on the combination of variable stability and cluster analysis to select the infrared spectrum variables. To reflect the advantages of VSCAA, we compared the classical variable selection methods (synergy interval partial least squares (SiPLS), genetic algorithm (GA), successive projections algorithm (SPA), and bootstrapping soft shrinkage (BOSS)) to extract useful wavelengths. The PLSR model, based on the useful variables selected by SiPLS-VSCAA, was optimal for measuring SSC in pears, and the correlation coefficient of calibration (Rc), root mean square error of cross validation (RMSECV), correlation coefficient of prediction (Rp), root mean square error of prediction (RMSEP), and residual predictive deviation (RPD) were 0.942, 0.198%, 0.936, 0.222%, and 2.857, respectively. Then, we applied these variable selection methods to select the characteristic wavelengths for measuring the TA content and TI value in snow pears. The prediction PLSR models, based on the variables selected by GA-BOSS to measure TA and that by GA-VSCAA to detect TI, were the best models, and the Rc, RMSECV, Rp and RPD were 0.931, 0.124%, 0.912, 0.151%, and 2.434 and 0.968, 0.080%, 0.968, 0.089%, and 3.775, respectively. The results showed that the self-made NIR-spectrum detector based on a portable NIR spectrometer with multivariate data processing was a good tool for rapid and nondestructive analysis of internal quality in pears.

Universal Synthesizer of Mueller Matrices Based on the Symmetry Properties of the Enpolarizing Ellipsoid

Polarimetry is today a widely used and powerful tool for nondestructive analysis of the structural and morphological properties of a great variety of material samples, including aerosols and hydrosols, among many others. For each given scattering measurement configuration, absolute Mueller polarimeters provide the most complete polarimetric information, intricately encoded in the 16 parameters of the corresponding Mueller matrix. Thus, the determination of the mathematical structure of the polarimetric information contained in a Mueller matrix constitutes a topic of great interest. In this work, besides a structural decomposition that makes explicit the role played by the diattenuation-polarizance of a general depolarizing medium, a universal synthesizer of Muller matrices is developed. This is based on the concept of an enpolarizing ellipsoid, whose symmetry features are directly linked to the way in which the polarimetric information is organized.

A highly efficient and thermally stable broadband Cr3+-activated double borate phosphor for near-infrared light-emitting diodes

GdAl3(BO3)4:Cr3+ is used to fabricate a NIR-pc-LED that shows promise for plant lighting and applications in the nondestructive analysis of agricultural products.