Ventilation theory

Etheridge, D., and M. Sandberg. 1996. Building Ventilation Theory and Measurements. John Wiley Sons, New York. 

Nielsen, P. V. 1993. Displacement Ventilation Theory and Design. Aalborg Universitv, Denmark. 

Ethridge, D., Sandberg, M. Building ventilation Theory and measurement. Chichester, John Wiley Sons, 1996. 

D. Etheridge, M, Sandberg. Building Ventilation Theory and Measurement. John Wiley A Sons, Chichester, 1996. 

Ventilation theory provides a simple means of estimating the consequences of the release of material inside a building. If a building of volume V m is ventilated with a volume of v m of fresh air per second, the ventilation rate or the number of air changes which occur in one hour in the space (N) = 3600v/y. The ventilation rate for typical structures is given below. 

Gnmitlyn, M. [. 1965. Fundamentals of isothermal and non- isothermal jets. Theory and design of ventilation jets. VNIIOT, Leningrad, pp. 27-56. 

Poz, M.. Y. 1993. Theoretical investigation and practical applications of non-isothermic jets for the purpose of ventilating rooms. ASHRAE Transactions, vol. 99, no. 1, pp. 950-9.39. Prandtl, L. 1942. Bemerkungen zur theorie der freien turbulenz. Z. fiir Angeivandie Math,. 

Scale-model experiments have been used to study a variety of ventilation problems as air movement in a room, air movement around a building, energy flow in a building, contaminant distribution at an operator s workplace, and smoke movement in a building on fire. The theory is discussed at a general level in the references. 

Nitrous oxide decreases tidal volume and increases the rate of breathing and minute ventilation. Although arterial carbon dioxide partial pressures tend not to be affected the normal ventilatory responses to carbon dioxide and to hypoxia are depressed. Alveolar collapse in structured lung segments may be more rapid in the presence of nitrous oxide than with oxygen due to its greater solubility. Similarly, it depresses mucous flow and chemotaxis. In theory these factors predispose to postoperative respiratoiy complications. 

Isolation of Source—Dust can best be controlled at the source of generation by enclosures, wet methods, or exhaust ventilation. The first of these methods, although obviously the simplest, cannot be used where the process requires attention by an operator. In theory this control method utilizes segregation of the dust-producing source. It is... 

The theory and practice of pneumatic conveying. Heat, and Ventil., 39 28-32. 

Conventional treatment of raised ICP in this condition consists of artificial ventilation, osmotherapy, and barbiturate administration. The value and duration of these measures has come under scrutiny. Prolonged hyperventilation has been discouraged, as the potential decrease in cerebral arterial blood flow resulting from additional hypocarbia might exacerbate tissue ischemia (34). Early use of agents such as glycerol or mannitol, at least in theory, may actually hasten tissue shifts and therefore lead to an aggravation of brain edema (35). Barbiturate therapy has to date failed to prove to be of therapeutic benefit in the treatment of postischemic brain edema (36). 

The data available on the molecular diffusion coefficient of organic vapors in air are meager, but they indicate (in accordance with approximate theory) an inverse proportionality to the square root of molecular weight. The rate of mass transfer by molecular diffusion will be proportional to the diffusion coefficient and to the SVC, itself proportional to vapor pressure times molecular weight (M). We should expect, therefore, under standard conditions of ventilation, that the rate of loss will be proportional to vapor pressure X The ratio of observed rate to... 

A hypothetical gassing scenario would proceed very differently if it could actually involve something that is occasionally alleged, namely that the Zyklon B was lowered into the gas chambers of crematoria II and III in nets, so that it could be quickly removed again after the victims had expired. This would have allowed for a more rapid ventilation of the chamber. But since this theory flounders on the nonexistence of the Zyklon B input hatches, we shall ignore it. 

In theory, there are three causes for the occurrence of HPS (since hypoventilation is not deemed a possible cause) (1.) arteriovenous shunts, (2.) disturbed alveolo-capillary oxygen diffusion in terms of impaired diffusion-perfusion, and (3.) mismatches between ventilation and perfusion. Consequently, there are numerous liver diseases which are associated with HPS. Transient HPS in acute viral hepatitis A and B has recently been reported. (17, 38) (s. tab. 18.1)... 

In cooperation with DSM, MCN developed a method of measurement for the determination of the formaldehyde release from particle board, based on a theorie for mass transfer, implying that under steady state conditions the emission of formaldehyde of a given particle board can and should be defined by two parameters of the particular board. These two parameters are (1) Ce defined as the equilibrium formaldehyde concentration (with ventilation rate 0") and (2) kgg defined as the overall mass transfer coefficient of the board. In (ideal mixed) climate rooms the stationary formaldehyde... 

Distributions of Ventilation-Perfusion Ratios Theory, J. Appl. Physiol. 1974,36, 588-599. 

In 1911 Winterstein (12) proposed his reaction theory of ventilatory control. This theory, which has progressively evolved over the years with the accumulation of new experimental findings and interpretations (13, 14), is based upon the idea that it is the hydrogen ion concentration [H+] in or near specific receptor cells which is the principal stimulus of respiration. Increased ventilation with increases in pco2 is explained on the basis that C02 has acid-forming properties in water—i.e.,... 

Empirical chemical equilib- Multiple factor theory used for ventilation rium relation between C02, which included arterial H+, pcG2, and p02. 

Ventilation ducts, 509 Viability of percolation theory, 523 Vibrational spectroscopies, 198 Violet nigraniline, 748 Viscosity, 525 Voltage, 750... 

The research of high-altitude mine ventilation optimization decision theory based on Analytical Hierarchy Process (AHP)... 

THE APPLICATION OF OPTIMIZATION DECISION THEORY ABOUT HIGH-ALTITUDE MINE VENTILATION SYSTEM... 

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