Polymer source-gated transistors with low saturation voltage

A type of injection-limited transistor is demonstrated with a conjugated polymer semiconductor and fluoropolymer insulator. The Source-Gated Transistor (SGT) is based on a source Schottky barrier, the effective height of...

Maximum ground level concentration Of air pollutant

The emission of an air pollutant from an elevated point source according to Gaussian plume model has been presented. Au. elementary theoretical treatment for both the highest possible ground-level concentration and the downwind distance at which this maximum occurs for different stability classes has been constructed. The effective height release modification was taken into consideration. An illustrative case study, namely, the emission from the research reactor in Inchas, has been studied. The results of these analytical treatments and of the derived semi-empirical formulae are discussed and presented in few illustrative diagrams.

Relationship Between Leaflets and Root in Normal Aortic Valve Based on Computed Tomography Imaging: Implication for Aortic Valve Repair

Objective: By assessing the normal dimensions and the relationship between the aortic root and leaflets in Chinese population, the objective of this three-dimensional computed tomography (3DCT)-based study was to establish a matching reference for leaflets and aortic root for aortic valve (AV) repair.Method: Electrocardiogram-gated multi-detector CT was performed on 168 Chinese participants with a normal aortic valve. Measurements of the aortic annuli and leaflets were obtained. The correlations between and the ratios of the specific root and leaflet measurements were analyzed. The references for the leaflet and root dimensions were suggested based on geometric height (gH) using a linear regression equation. The utility of the ratios was tested with CT images of 15 patients who underwent aortic valve repair.Result: The mean annulus diameter (AD), sino-tubular junction (STJ) diameter, geometric height (gH), effective height (eH), free margin length (FML), commissural height (ComH), inter-commissural distance (ICD), and coaptation height (CH) were 22.4 ± 1.7 mm, 27.3 ± 2, 0.4 mm, 15.5 ± 1.7 mm, 8.9 ± 1.2 mm, 32.0 ± 3.4 mm, 17.9 ± 1.9 mm, 23.1 ± 2.3 mm, and 3.1 ± 0.6 mm, respectively. The gH/AD, FML/ICD, and eH/ComH ratios were 0.69 ± 0.07, 1.38 ± 0.08, and 0.50 ± 0.07, respectively. The gH correlated with all other leaflet and root measurements (P < 0.01), whereas the FML demonstrated a better correlation with ICD compared with gH (R2 = 0.75, and R2 = 0.37, respectively). The FML/ICD and eH/ComH ratios might be used to assess leaflet-root mismatch and post-repair leaflet billowing.Conclusion: The normal aortic valve measurements based on 3DCT revealed a specific relationship between the root and leaflets; and this will guide the development of an objective method of aortic valve repair.

Methods for determining the effective height of the pipe taking into account the dispersion of emissions in the production facilities working area

Introduction. In order to determine the height of the rise of the polluted substances above the source of the pollution, it is important to know the exact distribution of the gas plume. Problem Statement. The determination of the dust concentration in the working area of asphalt concrete plants should take into account the assessment of the concentration of harmful substances in the working area of the asphalt concrete plant. The study is the analysis of methods for determining the effective height of the pipe, taking into account the dispersion of emissions in the working area. Theoretical Part. The paper considers the dependences of the estimation of the initial rise of the gas jet, proposed by Berland, Holland, Briggs, and the specialists of the Tennessee Valley. The value of the initial rise of the impurity jet depends on the moment of the amount of gas movement, the thermal power of the wind speed carrying the jet, and the conditions of thermophoresis. The paper presents the comparative graphs of the calculation of the level of the initial rise of the gas jet at different rates of gas exit from the pipe and constant wind speed. Conclusion. The method of taking into account the initial rise of the heated gas jet gives us better convergence in the calculations of the maximum surface concentrations of harmful substances and in the estimation of distances to them.