The effect of ITO films thickness on the properties of flexible organic light emitting diode

Indium tin oxide (ITO) thin films were deposited on cyclic olefin copolymer substrate at room temperature by an inverse target sputtering system. The crystal structure and the surface morphology of the deposited ITO films were examined by X-ray diffraction and atomic force microscopy, separately. The electrical properties of the conductive films were explored by four-point probing. Visible spectrometer was used to measure the optical properties of ITO-coated films. The performance of the flexible organic light emitting diode device with different thickness anode was investigated in this study.     

纳米尺寸的ZnO晶体高压相变的拉曼散射研究(英文)

Weperformedthehigh-pressureRaman measurementofthethreenanosizedZnOcrystals. Wefoundthesmallerthesize,thehigherthe pressuretoinducethephasetransitionfrom w櫣rzitetorock-saltstructure. High-pressureRamanmeasurementsof nona-shapedZnOcrystalswerepreformed.The…     

A co‐ordinate system independent streamwise upwind method for fluid flow computation

A new co‐ordinate invariant streamwise upwind formulation for convection dominated flows is developed. The eddy diffusivity/viscosity is added directly to the equations in order to remove the oscillations in the solution. The equations then can be solved by any high‐order scheme and the solution retains the accuracy of the high‐order scheme. The accuracy and reduced lateral thickness growth rate are demonstrated with several numerical examples, including pure convective flows and lid‐driven cavity flow. The lateral spreading due to the numerical diffusion is controlled by the anisotropic tensor. Copyright © 2004 John Wiley & Sons, Ltd.     

Low-Loss Fiber De-Multiplexers

Reported are fiber de-multiplexers based on side-polished fibers with a long interaction length and intra-core fiberBragg gratings. In conjunction with the silicon processing technologies, we demonstrate fiber filters and advantages ofour approaches are addressed.     

A high-gain porous silicon metal–semiconductor–metal photodetector through rapid thermal oxidation and rapid thermal annealing

2 tungsten lamp at 1.83 mA excited by a 0.85-mW 675-nm laser diode. We also demonstrate that the dark current could be greatly reduced through rapid thermal oxidation and rapid thermal annealing. Received: 4 August 1997/Accepted: 28 May 1998     

Effects of matrix-assisted laser desorption/ionization experimental conditions on quantitative compositional analysis of ethylene oxide/propylene oxide copolymers

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry has the potential to become a valuable tool for the compositional analysis of copolymers. For a copolymer composed of structurally very similar building blocks with minor chain length changes, one would expect the relative peak intensities observed in the MALDI mass spectra to reflect its composition, at least within a narrow mass range. However, we show that variations in experimental conditions in MALDI can have a significant effect on the mass spectral appearance of a copolymer. The effects of concentration, laser power, type of matrices and solvents on mass spectra of an ethylene oxide/propylene oxide copolymer are illustrated. These somewhat surprising results show that great care needs to be exercised when interpreting copolymer spectra for compositional analysis, even for copolymers with structurally similar monomers. This work also points out that further studies are needed to better understand and optimize spectral acquisition conditions for reliable copolymer compositional analysis by MALDI.     

Gradient elution capillary electrochromatography and hyphenation with nuclear magnetic resonance

Coupling of gradient capillary electrochromatography (gradient CEC) and capillary zone electrophoresis (CZE) with nuclear magnetic resonance spectroscopy (NMR) was performed using a recently developed capillary NMR interface. This technique was applied for the analysis of pharmaceuticals and food. An analgesic was investigated using isocratic and gradient continuous-flow CEC-NMR. Comparison of the results demonstrated the superiority of gradient CEC over isocratic CEC. Aspartame and caffeine, both ingredients of soft beverages, were separated and analyzed by continuous flow CZE-NMR. The order of elution could be reversed by altering the pH. This reversal led to an increased sample concentration in the NMR detection cell, thus allowing the acquisition of a totally correlated spectroscopy (TOCSY) two-dimensional (2-D) spectrum of the synthetic peptide aspartame.     

Photoisomerization and photodissociation of aniline and 4-methylpyridine

Photoisomerization and photodissociation of aniline and 4-methylpyridine at 193 nm were studied separately using multimass ion imaging techniques. Photofragment translational energy distributions and dissociation rates were measured. Our results demonstrate that more than 23% of the ground electronic state aniline and 10% of 4-methylpyridine produced from the excitation by 193 nm photons after internal conversion isomerize to seven-membered ring isomers, followed by the H atom migration in the seven-membered ring, and then rearomatize to both methylpyridine and aniline prior to dissociation. The significance of this isomerization is that the carbon, nitrogen, and hydrogen atoms belonging to the alkyl or amino groups are involved in the exchange with those atoms in the aromatic ring during the isomerization.     

PHOTODYNAMIC THERAPY INDUCED ULTRASTRUCTURAL ALTERATIONS IN MICROVASCULATURE OF THE RAT CREMASTER MUSCLE

Abstract— Photodynamic therapy disrupts blood flow to tumors and produces tumor necrosis. These effects may be due to a localized generation of singlet oxygen. The current studies used direct observations of the rat cremaster microvasculature to examine the vascular effects of PDT. The objective of the morphological examination was to delineate the structural basis for the altered blood flow in photodynamic therapy. Dihematoporphyrin ether given 30 min or 48 h prior to the experiment was activated with green light (wavelength530–560 nm, 120 J/cm²). After the in vivo activation the tissues were prepared for electron microscopy. Light alone induced little or no change in the luminal content or vessel wall. On exposure to activating light both acute (30 min) and long term (48 h) dihematoporphyrin ether pretreated samples displayed formation of luminal aggregates, granulocyte margination and migration, and endothelial cell and smooth muscle cell damage. The latter was more pronounced in the arterioles than the venules. Perivascular changes included interstitial edema and damage to striated myocytes. Some of the alterations such as interstitial edema may be transient; however, smooth and skeletal muscle cell injury are important in normal and tumor tissue necrosis after photodynamic therapy.     

Comparative study on conventional and low-flow nebulizers for arsenic speciation by means of microbore liquid chromatography with inductively coupled plasma mass spectrometry

The performance of conventional and low-flow nebulizer systems with liquid chromatography in differentiating four arsenic species in urine was evaluated. Two low-flow (DIN and MCN) chamber assemblies and a conventional (CFN) nebulizer-spray chamber assembly were compared in the hyphenation of anion-exchange microbore liquid chromatography with inductively coupled plasma mass spectrometry. Under optimal analytical conditions, the detection limits of the four arsenic species were 0.2-0.6 ng ml(-1) for all the nebulizer systems tested. The chromatographic resolution was best in the case of DIN due to its minimal off-column dead volume and superior transport efficiency. Four arsenic species were determined in the certified reference materials NIST SRM 2670E and 2670N.