Blockage/obstruction

In measuring the local velocity in ducts, the sensor will obstruct a part of the duct cross-section. This results in accelerated flow by the sensor and an error occurs. In a Pitot-static tube, this is called stem blockage. If the ratio of the tube diameter to the duct diameter is smaller than 0.02, stem blockage can be neglected. Otherwise a correction has to be applied. 

A tube 10 m long and 2.5 m inside diameter was used for experiments with methane (Moen et al. 1982) and propane (Hjertager et al. 1984). These often-cited experiments showed that very intense gas explosions were possible in this tube, which had an aspect ratio of only 4 but which contained internal obstructions. Pressures of up to 4.0 bar for methane and 13.9 bar for propane were reported. Obstruction parameters, for example, blockage ratio and pitch, were varied. As with cylindrical geometry, explosions became more severe with increasing obstacle density. 

Conjugated hyperbilirubinemia commonly results from blockage of the hepatic or common bile ducts, most often due to a gallstone or to cancer of the head of the pancreas. Because of the obstruction, bilirubin diglu-curonide cannot be excreted. It thus regurgitates into the hepatic veins and lymphatics, and conjugated bilirubin appears in the blood and urine (choluric jaundice). 

Functional constipation (constipation occurring in the absence of a demonstrated pathologic condition) involves the presence of at least two of the following symptoms straining, lumpy or hard stools, sensation of incomplete evacuation, sensation of anorectal obstruction or blockage, need for manual maneuvers to facilitate defecation and/or, infrequent (fewer than three) bowel movements per week. 

Oral- Rarely, some tablets may cause bowel obstruction or blockage, usually... 

Blockage or plugging of the dipleg due to an obstruction or catalyst bridging resulting from defluidization or sticky catalyst fines will effectively flood the cyclone, rendering the cyclone inoperative. 

Obstructive jaundice, as the name implies, is caused by blockage of the bile duct by a gallstone or a tumor (usually of the head of the pancreas). 

Obstructive sleep apnea involving blockage of the oropharynx... 

Infarction Loss of blood supply due to obstruction (e.g., myocardial infarct due to the blockage caused by a blood clot). 

No fluid exits the system a complete obstruction exists within the drainage apparatus. Usually, it is impossible to inject any fluid into the system at the time of testing due to the complete blockage (i.e., no fluid goes in, no fluid comes out). 

Fig. 6.9 Blockage and dilation of the intrahepatic bile ducts ( lakeland plain ) in obstructive jaundice...

As for the terrestrial vegetation, the difficulty appeared here concerns to the problem of the estimate of the vegetation stiffness that may be also called the density of the obstruction layer (the canopy). In the field measurements of Bennovitsky [53, 54], the natural vegetation (the reed) provided the blockage 7,40, and 120 plants on m2. In the measurements of Nepf [463], the blockage of plants was 330 plants/m2. Another measure for the canopy density, the frontal area per unit volume s, 1 /m, has been more universal. Its typical vertical distribution is shown in Fig. 1.7, [463],... 

In cholestasis, bile salts and bile pigments are retained and appear in the circulation, and steatorrhea and deficiencies of fat-soluble vitamins may occur. These deficiencies are often manifested as hypoprothrombinemia (from lack of vitamin K) and osteomalacia (from lack of vitamin D). The magnitude depends on the degree of obstruction. If blockage is complete, urinary urobilinogen will be absent and the stools will have a pale, clay-like color. 

Indications Wind stroke, qi stroke, or cold stroke, i.e., blockage and obstruction by cold evils, phlegm turbidity, or qi depression. Partial or total loss of consciousness due to cerebrovascular accident, uremia, or hepatic coma, encephalitis, hysteria, seizure disorders, psychosis, schizophrenia, postconcussion syndrome, dry sudden chaos (i.e., cholera-like) disease, and angina pectoris, and coronary heart disease... 

For blockage and obstruction to swallowing with glomus and fullness of the chest and diaphragm, a slimy, white tongue coating, and a wiry, slippery pulse, add Tuber Curcumae (Yu Jin) and Fructus Amomi (Sha Ren). 

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