Dehydration, inadequate

The most obvious indication of a glycol dehydration malfunction is a high water content or dew point of the outgoing sales gas stream. In most cases, this is caused by an inadequate glycol circulation rate or by an insufficient reconcentration of the glycol. These two factors can be caused by a variety of contributing problems listed below. 

In its simplest form, an adsorber is normally a cylindrical tower filled with a solid desiccant. The depth of the desiccant may vary from a few feet to 30 ft or more. The vessel diameter may be from a few inches to 10 or 15 ft. A bed height to diameter (L/D) ratio of higher than 2.5 is desirable. Ratios as low as 1 1 are sometimes used however, poor gas dehydration, caused by non-uniform flow, channeling and an inadequate contact time between the wet gas and the desiccant sometimes result. 

D Deficient Fluid Volume related to inadequate fluid intake, need to inotease dose of drug, failure to recognize symptoms of dehydration (diabetes insipidus)... 

The advance of sulfur trioxide as sulfating agent largely depended on advances in sulfonation/sulfation reactor development and changes in raw material quality. Undiluted sulfur trioxide cannot be used as a sulfating agent except in special cases where suitable equipment is used because of its violent nature. Sulfur trioxide diluted in an inert gas, usually air, when used in batch processes can cause excessive dehydration and dark-colored products. However, batch processes were used years ago and inert liquid solvents were often suggested or used to moderate the reaction. Inadequate reaction conditions lead to a finished product that can contain dialkyl sulfate, dialkyl ether, isomeric alcohols, and olefins whereas inadequate neutralization conditions can increase the content of the parent alcohol due to hydrolysis of the unstable acid sulfate accompanied by an increase of mineral sulfate. 

Nausea Loss of appetite without alteration in eating habits Oral intake decreased without significant weight loss, dehydration or malnutrition IV fluids indicated less than 24 hours Inadequate oral caloric or fluid intake IV fluids, tube feedings, or TPN indicated greater than 24 hours Life-threatening consequences Death... 

Rapid transit through this region suggests that the area is empty of colonic contents most of the time, and so the opportunity for topical treatment is consequently limited. If the exposure to a drug such as mesalazine is calculated on the basis of these data, the results show that treatment is probably inadequate. For example, the dose per day is approximately 3 g (800-1200 mg, t.d.s.), and so in active disease the effective dose would be about 300 mg on the basis of this regimen. Doses of 500-1000 mg are often given as a enema, but these doses are more effectively delivered and not sequestered within a viscous, partially dehydrated stool, as would be the case following oral administration. 

If the nonlinear estimation procedure is carefully applied, a minimum in the sums-of-squares surface can usually be achieved. However, because of the fitting flexibility generally obtainable with these nonlinear models, it is seldom advantageous to fit a large number of models to a set of data and to try to eliminate inadequate models on the basis of lack of fit (see Section IV). For example, thirty models were fitted to the alcohol dehydration data just discussed (K2). As is evident from the residual mean squares of Table II, approximately two-thirds of the models exhibit an acceptable fit of the data... 

The material is best heated in a tube between 90° and 110° so that the first portion of the water may be expelled without fusion. The temp, is then raised to 220°, and the operation concluded by a 4 hrs. heating at 240°, dry and purified air is passed through the tube during the operation. If fusion occurs before dehydration, some iodic acid may be enclosed within an impervious coating of anhydrous salt, and the escape of water prevented. If the air is inadequately dried, the iodine pentoxide may become brown, probably owing to the liberation of iodine and a similar result is obtained when the temp, rises over 250°. 

Children with cystic fibrosis lose excessive amounts of salt in perspiration and become dehydrated readily. A salty taste of the skin and an elevated chloride concentration of sweat are traditional diagnostic symptoms.3 More serious problems arise from progressive respiratory failure and inadequate pancreatic secretion. Lung infections with Pseudomonas aeruginosa are the major cause of death. The CFTR gene is expressed in many tissues, especially those of the mucous membranes. 

Also known as water diabetes, diabetes insipidus (DI) is a rare chronic disease that causes excessive urination. If not properly treated, it can result in electrolyte imbalance and dehydration. It may be caused by a number of factors, including lithium use (a psychiatric drug used for bipolar disorder), neurological disease, or an inadequate amount of ADH (anti-diuretic hormone, or vasopressin, which is produced by the pituitary gland). DI caused by insufficient ADH is called central diabetes insipidus. 

Small amounts of water within a zeolite can have a large effect on some experiments, so complete dehydration is often necessary. A zeolite which is to be exposed to alkali-metal vapor, for example, must not be given an opportunity to resorb water fi-om other parts of its vessel after dehydration but before metal vapor sorption. The resulting metal hydroxide or oxide (additional products) could lead to the destruction of the zeolite. To compound the problem, the experimental conditions are often not described in detail in a report in the literature, so the reader can only be suspicious of a link between the reported result and inadequate dehydration. For some work, involving large amounts of powder, this problem may sometimes be of minor importance. Where tiny samples are involved, it is crucial. 

Hypotonic dehydration as a result of the loss of sodium from long-term diuretic therapy and from diarrhoea as well as due to inadequate sodium intake (= extracellular space decreased, intracellular space increased, overall sodium status depressed, surplus of free water, hypo-osmolality and hyponatraemia). 

The total protein concentration of serum obtained from a healthy ambulatory adult is 6.3 to 8.3 g/dL and 6.0 to 7.8 g/dL from an adult at rest. The two general causes of alterations of serum total protein are a change in the volume of plasma water and a change in the concentration of one or more of the specific proteins in the plasma. Decrease in the volume of plasma water (hemoconcentration) is reflected as relative hyperproteinemia concentrations of all the individual plasma proteins are increased. Hyperproteinemia is noted in dehydration caused by inadequate water intake or excessive water loss as in severe vomiting, diarrhea, Addison s disease, or diabetic acidosis. Hemodilution (increase in plasma water volume) is reflected as relative hypoproteinemia concentrations of aU the individual plasma proteins are decreased. Hemodilution occurs with water intoxication or salt retention syndromes, during massive intravenous infusions, and physiologically when a recumbent position is assumed. A recumbent position decreases total protein concentration by 0.3 to 0.5 g/dL and many individual proteins including albumin by up to 10%. 

The extent to which surface transport affects global rates of reaction has not been established. For it to be important, adsorption must occur, but this is also a requirement for catalytic activity. Indirect evidence suggests that in some cases the effect is considerable. For example. Miller and Kirk found higher rates of dehydration of alcohols on silica-alumina than could be explained with only pore-volume diffusion to account for intraparticle resistances. They attributed the discrepancy to surface diffusion. Masamune and Smith found that surface transport of ethanol on silica gel at temperatures as high as 175°C predominated over gas-phase diffusion in the pore. In view of the data available, it seems wise at least to consider the possibility of surface migration in any evaluation of intraparticle effects. This can be done by adding a surface-diffusion contribution to the effective diffusivity considered in the previous section. The method of doing this is presented below, but its usefulness is still limited because of inadequate experimental and theoretical aspects of surface transport. 

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