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Although a significant amount of work has been performed to preserve the ancient murals in the Mogao Grottoes by Dunhuang Cultural Research, non-contact methods need to be developed to effectively evaluate the degree of flaking of the murals. In this study, we propose to evaluate the flaking by automatically analyzing hyperspectral images that were scanned at the site. Murals with various degrees of flaking were scanned in the 126th cave using a near-infrared (NIR) hyperspectral camera with a spectral range of approximately 900 to 1700 nm. The regions of interest (ROIs) of the murals were manually labeled and grouped into four levels: normal, slight, moderate, and severe. The average spectral data from each ROI and its group label were used to train our classification model. To predict the degree of flaking, we adopted four algorithms: deep belief networks (DBNs), partial least squares regression (PLSR), principal component analysis with a support vector machine (PCA + SVM) and principal component analysis with an artificial neural network (PCA + ANN). The experimental results show the effectiveness of our method. In particular, better results are obtained using DBNs when the training data contain a significant amount of striping noise.

A new unsymmetric guest compound comprising ferrocene and azobenzene moieties was synthesized and can form a host-guest system with beta-cyclodextrin (beta-CD) complexed. The complexation stoichiometries and sites of the ensembles can be selectively controlled by reversible redox and photoirradiation.

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The thiolato complex [Pt(II)(bipyridine)(N,S-aminoethanethiolate)]+ Cl- (1) undergoes sequential reactions with singlet oxygen to initially form the corresponding sulfenato complex [Pt(II)(bipyridine)(N,S(=O)-aminoethansulfenate)]+ (2) followed by a much slower reaction to the corresponding sulfinato complex. In contrast with many Pt dithiolato complexes, 1 does not produce any singlet oxygen, but its rate constant for singlet oxygen removal (kT) is quite large (3.2 × 107 M-1sec-1) and chemical reaction accounts for ca. 25 % of the value of kT). The behavior of 1 is strikingly different from the complex Pt(II)(bipyridine)(1,2-benzenditholate) (4). The latter complex reacts with 1O2 (either from an external sensitizer or via a self-sensitized pathway) to form a sulfinato complex. These two very different reactivity pathways imply different mechanistic pathways: The reaction of 1 with 1O2 must involve O-O bond cleavage and intermolecular oxygen atom transfer, while the reactive intermediate in complex 4 collapses intramolecularly to the sulfinato moiety.