Breathing frequency

TABLE 5.6 Effect of Dead Space Volume, Tidal Volume, and Breathing Frequency on Alveolar >fentllation at a Fixed Minute Ventilation (V = 58.0 Umin). Modified from Chemiack. ... 

Panicles entrained in the airstream deposit along the airway as a function of size, density, airstream velocity, and breathing frequency. Sizes of rougjily spherical or irregularly shaped particles arc commonly characterized by relating the settling velociiy of the particle to that of an idealized spherical particle. For example, an irregular particle which settles at the same rate as a 5 pm spherical particle has a mean mass aerodynamic diameter (MMAD) of. 5 pm. Since spherical particle mass, is a function of particle diameter, J... 

Most lung deposition models are based on the influence of particle size on aerosol deposition. Breathing parameters, such as breathing frequency and tidal volume, play a key role in lung deposition [15]. Table 2 shows the breathing parameters for healthy male volunteers subjected to various levels of exercise on a bicycle ergometer [16], There are known differences in these parameters based on gender, age, and disease... 

Total ventilation. The total ventilation (minute volume) is the volume of air that enters the lungs per minute. It is determined by tidal volume and breathing frequency ... 

Total ventilation = tidal volume x breathing frequency = 500 ml/breath x 12 breaths/min = 6000 ml /min... 

With an average tidal volume of 500 ml/breath and breathing frequency of 12 breaths/min, 6000 ml or 61 of air move in and out of the lungs per minute. These values apply to conditions of normal, quiet breathing tidal volume and breathing frequency increase substantially during exercise. 

During exercise, the increase in minute ventilation results from increases in tidal volume and breathing frequency. Initially, the increase in tidal volume is greater than the increase in breathing frequency. As discussed earlier in this chapter, increases in tidal volume increase alveolar ventilation more effectively. Subsequently, however, as metabolic acidosis develops, the increase in breathing frequency predominates. 

Table VI Equilibrium Metal-Oxygen Distances and (for Fe) Breathing Frequencies in Aquo Complexes. ...

Bell suggested that the quasisteady flow is probably a valid approximation at quiet-breathing frequencies and that velocity and pressure profiles in the lung during quiet breathing can be obtained from experimental steady-flow data. The same conclusions cannot be generally applied to experimental particle deposition or gas-transfer measurements. 

The spectra of methane, adsorbed at 90° K., showed a weak band at 2,899 cm.", in addition to a strong band (vt) at 3,006 cm. h This weak band was assigned to the I l symmetrical breathing frequency of methane, which is normally observed only in the bulk state in the Raman spectrum at 2,916 cm. h No over-all dipole change is associated with the vi vibration consequently, it is forbidden in the infrared spectra of liquid and gaseous methane. The appearance of this band is a direct measure of the... 

As mentioned previously, there are no test guideline methods for respiratory irritation. Good data, often clearly related to exposure levels, can be obtained on respiratory and mucous membrane irritation, from well-designed and well-reported inhalation studies in animals. Also the Alarie test (Alarie 1973, 1981), an experimental animal test assessing the concentration that results in a 50% reduction of the breathing frequency, may provide useful information on sensory irritation of the upper respiratory tract and the results may be used for hazard identification. 

Raman spectra of adsorbed species, when obtainable, are of great importance because of the very different intensity distributions among the observable modes (e.g., the skeletal breathing frequency of benzene) compared with those observed by infrared spectroscopy and because Raman spectra of species on oxide-supported metals have a much wider metal oxide-transparent wavenumber range than infrared spectra. Such unenhanced spectra remain extremely weak for species on single-crystal surfaces, but renewed efforts should be made with finely divided catalysts, possibly involving pulsed-laser operation to minimize adsorbate decomposition. Renewed efforts should be made to obtain SER and normal Raman spectra characterizing adsorption on surfaces of the transition metals such as Ni, Pd, or Pt, by use of controlled particle sizes or UV excitation, respectively. 

The position of the symmetrical ring-breathing frequency, vs, is also in some doubt. This vibrational mode would be IR-inactive for a molecule of D5h symmetry and only weakly active for a molecule of... 

The symmetrical stretching, or ring breathing frequency, of the epoxy ring, all ring bonds stretching and... 

Regional deposition is dependent on the aerodynamic properties of the particles, usually described in terms of the aerodynamic particle diameter, airway dimensions, and such respiratory characteristics as flow rate, breathing frequency, and tidal volume. 

A. The breathing frequency will have probably two quanta here. Total vibration energy about 2600 cm. h... 

Pattern Tidal volume (ml) Breathing frequency (1/min) Nebulization... 

Fig. 4.—Two of the Normal Vibrations of Tetrahydropyran (A) Symmetrical Ring Breathing Frequency (B) Antisymmetrical Ring Bending Frequency. (The arrows represent displacements of the nuclei from their equilibrium positions. Vertically-lined circle = oxygen above xy plane, carbon above xy plane, O carbon below xy plane.)...

A preliminary investigation of furanose derivatives was made by Barker and Stephens in which tentative assignments were allocated. A ring breathing frequency at 924 13 cm.- was made, along with a C—H deformation mode (799 =fc 17 cm. ) where the hydrogen atom was present... 

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