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This study reveals that the stoichiometricity of silicon nitride thin films (SiNx-TFs) significantly governs the packing density and water vapor transmission rate (WVTR), and it can be controlled by chemical reactions accompanied by the removal of oxygen impurities with a nitrogen neutral beam (N-NB). Here, oxygen contents of SiNx-TFs are reduced through the formation of volatile NOx, and their amount is dominated by the energy of the N-NB reflected from a negatively biased reflector (0 to −60 V). The single-layered stoichiometric SiNx-TFs with a thickness of 100 nm provides the WVTR of 6.2 × 10−6 g/(m2day), with a density and composition ratio of N/Si stoichiometry at 3.13 g/cm3 and 1.33, respectively. This optimized SiNx-TF encapsulated top-emission organic light-emitting diode has reliability under harsh condition (85 °C and 85% relative humidity) for 830 h or more. [ABSTRACT FROM AUTHOR]

An electrically controllable, solid-state, reversible device for sourcing and sinking alkali vapor is presented. When placed inside an alkali vapor cell, both an increase and decrease in the rubidium vapor density by a factor of two are demonstrated through laser absorption spectroscopy on 10-15 s time scales. The device requires low voltage (5 V), low power (<3.4 mW peak power), and low energy (<10.7 mJ per 10 s pulse). The absence of oxygen emission during operation is shown through residual gas analysis, indicating that Rb is not lost through chemical reaction but rather by ion transport through the designed channel. This device is of interest for atomic physics experiments and, in particular, for portable cold-atom systems where dynamic control of alkali vapor density can enable advances in science and technology. [ABSTRACT FROM AUTHOR]

Using the shadowgraph technique, we performed direct measurements of the vapor density in the discharge channel of a pulsed positive streamer discharge in water. With this experimental technique, we quantitatively measured the vapor density in the discharge channel of a pulsed positive streamer discharge in water of conductivity 100 μS/cm. The results show that the vapor density in the discharge channel ranges from 100 to 660kg/m³, and presents an increasing tendency along the axial direction of the discharge channel with increasing distance from the tip of the anode. [ABSTRACT FROM AUTHOR]

Evaporation momentum force arises due to the difference in liquid and vapor densities at an evaporating interface. The resulting rapid interface motion increases the microconvection heat transfer around a nucleating bubble in pool boiling. Microstructure features are developed on the basis of this hypothesis to control the bubble trajectory for (i) enhancing the heat transfer coefficient, and (ii) creating separate liquid and vapor pathways that result in an increased critical heat flux (CHF). An eightfold higher heat transfer coefficient (629 000 W/m2 °C) and two-and-half times higher CHF (3 MW/m2) over a plain copper surface were achieved with water. [ABSTRACT FROM AUTHOR]

Total vapor-phase densities of Dy in equilibrium with a DyI3/InI condensate and Tm in equilibrium with a TmI3/TlI condensate have been measured for temperatures between 900 K and 1400 K. The measurements show strong enhancements in rare-earth vapor densities compared to vapors in equilibrium with the pure rare-earth metal-halides. The measurements were made with x-ray induced fluorescence on the sector 1-ID beam line at the Advanced Photon Source. The temperature range and salt mixtures are relevant to the operation of metal-halide high-intensity discharge lamps. [ABSTRACT FROM AUTHOR]

We demonstrate that coherent random lasing can occur in solid-state dispersions of laser dyes 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran and 4-dicyanomethylene-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran within a tris(8-hydroxy-quinolinato)aluminum matrix without the need for infiltrated scatterers. Random lasing thresholds as low as 90 μJ/cm2 are observed in 250 nm-thick films with 2-2.5% dye concentration. We find that the lasing threshold exhibits a power law decay with sample area, providing a simple test for the occurrence of random lasing. We discuss the implications of this result in the context of previous reports of lasing in these materials where feedback was provided by conventional optical resonators. [ABSTRACT FROM AUTHOR]

Presents an atomic absorption monitor for deposition process control of aluminum vapor density at 394 nanometer. Use of frequency-doubled external-cavity-diode-laser; Achievement of closed loop operation; Illustration of the reproducibility of the system; Possibility of controlling the sputtering process.