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In situ near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and density functional theory calculations were conducted to demonstrate the decomposition mechanism of propylene glycol methyl ether acetate (PGMEA) on a MnO2–CuO catalyst. The catalytic activity of MnO2–CuO was higher than that of MnO2 at low temperatures, although the pore properties of MnO2 were similar to those of MnO2–CuO. In addition, whereas the chemical state of MnO2 remained constant following PGMEA dosing at 150 °C, MnO2–CuO was reduced under identical conditions, as confirmed by in situ NEXAFS spectroscopy. These results indicate that the presence of Cu in the MnO2–CuO catalyst enables the release of oxygen at lower temperatures. More specifically, the released oxygen originated from the Mn–O–Cu moiety on the top layer of the MnO2–CuO structure, as confirmed by calculation of the oxygen release energies in various oxygen positions of MnO2–CuO. Furthermore, the spectral changes in the in situ NEXAFS spectrum of MnO2–CuO following the catalytic reaction at 150 °C corresponded well with those of the simulated NEXAFS spectrum following oxygen release from Mn–O–Cu. Finally, after the completion of the catalytic reaction, the quantities of lactone and ether functionalities in PGMEA decreased, whereas the formation of C=C bonds was observed.

The microstructure of abnormal grains in Al-doped ZnO (AZO) films using a seed layer was examined with the aim of enhancing the performance of transparent conducting oxides in thin film solar cells. The AZO films were prepared by DC-pulsed magnetron sputtering using a two-step process. The seed layer was deposited on a glass substrate under an Ar/O2 atmosphere with a gas flow ratio of 24/1, and the bulk layer was formed on the seed layer in pure Ar. The microstructural properties of the AZO films were investigated by transmission electron microscopy (TEM), fast Fourier transform simulation, and strain analysis with high-resolution TEM images. The TEM revealed peculiar microstructures on the AZO film showing abnormal grains and a rough surface. The AZO seed layer was formed at a thickness of 50 nm, and two types of grains with columnar and hillock structures were formed on the seed layer. Elemental analysis using energy dispersive X-ray measurement showed that the abnormal grains contained more metallic elements (Al and Zn) than the normal region with columnar structure in the AZO film. The analysis of fast Fourier transform images of each region showed that the crystal structures of the normal and abnormal grains were the same, whereas the abnormal grain had a different growth orientation from that of the normal region. Copyright © 2012 John Wiley & Sons, Ltd.

We studied the growth mechanism of Al-doped ZnO (AZO) films using seed layers for enhancing the performance of transparent conducting oxides (TCOs) in the thin film solar cells. We carried out two-step processes for the deposition of AZO films. Seed layers were deposited on glass substrate as a function of Ar/O2 gas flow ratio. We show the results of our investigation on the micro-structural properties of AZO seed layers using transmission electron microscopy (TEM). The elemental composition and electronic structure changes with the deposition conditions were examined using energy dispersive X-ray (EDX) and reflective electron energy loss spectroscopy (REELS). The optical and electrical characteristics of AZO film using the seed layer with Ar/O2 = 9/1 show a high haze value of 88% at 500 nm and a resistivity value of 3.7 × 10 Ω·cm.

The authors describe a case in which a tailgut cyst occurred at an unusual location in a 22-year-old woman referred for abdominal discomfort and urinary frequency. The left abdomen contained a palpable mass, found at imaging studies to be a homogeneous, unilocular and cystic, and anterior to the left kidney. After surgical excision, it was shown to be a tailgut cyst.

Reconstruction and exaggerated grain growth (EGG) behaviors of redeposited MgO layer were observed and analyzed theoretically with the addition of dopant and MgO seed particle. The reconstruction and EGG are closely correlated with the driving force for nucleation and growth, interface energy and initial size distribution of MgO protective layer and this is believed to be caused by the formation of charged clusters in the plasma spaces during discharge in AC-PDPs.