Development of an optical flow through detector for bubbles, crystals and particles in oils

Significant quantities of 9-micron microspheres (20-30%) are not trapped in the intestine following intracardiac or intra-arterial injection, but reach venous blood. Some investigators propose that the passage of 9-micron spheres measures blood flow through noncapillary connections. Because frequency distributions of intestinal capillary diameters and 9-micron spheres overlap, microspheres could simply pass through capillaries. Therefore, we developed simple probabilistic models to predict both the size distribution and the percentage of injected spheres [9 +/- 1 (SD) micron] that should appear in venous blood. Chief assumptions in models are that microsphere delivery and sphere diameter are independent and that microspheres pass through capillaries of equal or larger size. The passage predicted by the models was consistent with values in canine intestinal circulation, demonstrating that passage through capillaries [7.38 +/- 1.4 (SD) micron] adequately accounts for spheres in venous blood. Because the diameters of nominal 9-micron spheres were distributed too narrowly to show a marked sieving effect on passage through the intestinal circulation, we also injected microspheres varying from 5 to 20 micron in diameter. This mixture demonstrated a marked sieving effect. The predicted frequency distribution for microsphere diameters in venous blood agreed with the observed distribution. Our models demonstrate that the passage of 9-micron spheres through capillaries, rather than through “shunts,” adequately accounts for the appearance of spheres in venous blood and suggests that the frequency distribution of venous microspheres can provide an in vivo method for estimating the frequency distribution of intestinal capillary diameters.

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A Fully Automated Sequential-Injection Analyser for Dual Electrogenerated Chemiluminescence/Amperometric Detection

Journal of Automated Methods and Management in Chemistry ◽

10.1155/jammc/2006/67571 ◽

2006 ◽

Vol 2006 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Anastasios Economou ◽

Maria Nika

Keyword(s):

Thin Layer ◽

Optical Flow ◽

Amperometric Detection ◽

Electrogenerated Chemiluminescence ◽

Sequential Injection Analysis ◽

Peristaltic Pump ◽

Sequential Injection ◽

Experimental Sequence ◽

Flow Through ◽

The Individual

This work describes the development of a dedicated, fully automated sequential-injection analysis (SIA) apparatus suitable for simultaneous electrogenerated chemiluminescence (ECL) and amperometric detection. The instrument is composed of a peristaltic pump, a multiposition selection valve, a home-made potentiostat, a thin-layer electrochemical/optical flow-through cell, and a light detector. Control of the experimental sequence and simultaneous data acquisition of the light and the current intensities were performed in LabVIEW6.1. The CL reagents and the sample were first aspirated as distinct zones into the holding coil of the analyser and, then, delivered to the cell; during their travel, the individual zones mixed and the ECL reaction was initiated as soon as the mixed regents reached the cell. The utility of the analyser was demonstrated for the detection of oxalate andH2O2based on their ECL reactions withRu(bpy)32and luminol, respectively.

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Local sound field reproduction using digital signal processing

The Journal of the Acoustical Society of America ◽

10.1121/1.416060 ◽

1996 ◽

Vol 100 (3) ◽

pp. 1584-1593 ◽

Cited By ~ 57

Author(s):

Ole Kirkeby ◽

Philip A. Nelson ◽

Felipe Orduna‐Bustamante ◽

Hareo Hamada

Keyword(s):

Signal Processing ◽

Digital Signal Processing ◽

Sound Field ◽

Digital Signal ◽

Local Sound

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Inlet and Exit-Header Shapes for Uniform Flow Through a Resistance Parallel to the Main Stream

Journal of Basic Engineering ◽

10.1115/1.3658963 ◽

1961 ◽

Vol 83 (3) ◽

pp. 361-368 ◽

Cited By ~ 5

Author(s):

Morris Perlmutter

Keyword(s):

Experimental Study ◽

Pressure Drop ◽

Total Pressure ◽

Experimental Results ◽

Main Stream ◽

Height Ratio ◽

Large Length ◽

Flow Through ◽

Pass Through ◽

Good Agreement

An analytical and experimental study of flow in headers with a resistance parallel to the turbulent and incompressible main stream has been made. The purpose was to shape the inlet and exit headers, which had a large length-to-height ratio, so that the fluid would pass through the resistance uniformly. Analytical wall shapes and estimated total pressure drop through the headers were compared with experimental results. Good agreement between analysis and experiment was found for the cases compared.

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