System compensation

Double-beam AA spectrophotometers are still marketed by instrument manufacturers. A double-beam system compensates for changes in lamp intensity and may require less frequent re-zeroing than a single-beam instrument. These considerations had more merit some years ago when hollow cathode lamps suffered from some instability. It should be noted, however, that the optical... 

At the positive electrode the electronic current results in an increasing electron density. The electrode B/electrolyte system compensates this process by the consumption of electrons for the deposition of B+ ions ... 

The mechanisms by which tolerance develops are not completely understood. As noted above, diminished release of nitric oxide may be partly responsible for tolerance to nitroglycerin. Systemic compensation also plays a role in tolerance in the intact human. Initially, significant sympathetic discharge occurs and after one or more days of therapy with long-acting nitrates, retention of salt and water may reverse the favorable hemodynamic changes normally caused by nitroglycerin. 

Such variability is apparent very early in life. For example, retinal L and Z also vary by a factor of more than 10 in the infant retina,20 which is probably due to variation in the amount of L and Z present in breast milk and infant formula.21 The visual system compensates for this large variation in the screening of light across the retina (e.g., from 0 to 1.6 OD (optical density) within 2 mm14) by increasing gain specifically within the yellow-blue color opponent system.22 23... 

Density compensation may also be accomplished through electronic circuitry. Some systems compensate for density changes automatically through the design of the level detection circuitry. Other applications compensate for density by manually adjusting inputs to the circuit as the pressurizer cools down and depressurizes, or during heatup and pressurization. Calibration charts are also available to correct indications for changes in reference leg temperature. 

Q6 The respiratory system compensates for alkalosis by retaining C02. The central chemoreceptors in the medullary respiratory centres respond to the reduced H+ by decreasing alveolar ventilation, which will increase blood arterial PC02 and return the pH to normal (7.4). 

Using the above result, show that the total potential at an ion for a charged system compensated by a neutralizing background is... 

Supel, T. M. (1990), Equivalence and Redundancy in the Point-Factor Job Evaluation System, Compensation and Benefits Review, Vol. 2, pp. 48-55. 

Since spoken word inteUigibihty is dependent on accurate consonant perception, designers of specialized systems, such as hearing aids or radio reading services for the elderly, should make appropriate system compensations. 

Figure 4 is a schematic representation of a Perkin-Elmer DSC 2 differential scanning calorimeter, whose principles are given by Gray [17]. The calorimeter head is constituted of two identical plates in continuous contact with a cold source and heaters that supply the required energy to impose the programmed temperature Tp to the plates. The heaters run independently, and an electronic system compensates for temperatures between the plates. 

Le Chatelier s Principle When a chemical equilibrium exists, any disturbance of the system wiU result in the system compensating. 

One might think that as long as the thickness of reaction layer is less then 1000 A its resistance to transport has to be negligible. In reality the transport resistance in this case without stirring is determined by both chemical and diffusion steps. Their reciprocal dependencies on the linear dimension of the system compensate each odier and the transport resistance in this case is not a function of any distance at all. Theoretical analysis of the influence of stirring is discussed in (7). 

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