Constant operating range

Fig. 10. Economic operating range of extractors. Superscripts a and b are constants.

Assumption 3 The variance of the random error term is constant over the ranges of the operating variables used to collect the data. When the variance of the random error term varies over the operating range, then either weighted least squares must be used or a transformation of the data must be made. However, this may be violated by certain transformations of the model. 

The anode material must have a more or less constant operating potential over a range of current outputs. Consequently the anode must resist polarisation when current flows the polarisation characteristics must also be predictable. 

A substance or device (synonymous with neutral density filter) that reduces the radiant power of incident radiation by a constant factor over all wavelengths within the instrument s operating range. See also Filter... 

The purpose of a multiviscosity motor oil is to offer good engine protection over the operating range of the engine from a cold start to the normal operation temperature. Addition of a low Tg polymer allows for a wider range where viscosity is approximately constant. 

Micro-HPLC operation sets special demands on the gradient instrumentation. As the internal column diameter, d, decreases, lower flow rates should be used at comparable mean linear mobile phase velocities, u = 0.2-0.3 mm/s. At a constant operating pressure, the flow rate decreases proportionally to the second power of the column inner diameter, so that narrow-bore LC columns with 1mm i.d. require flow rates in the range of 30-100pL/min, micro-columns with i.d. 0.3-0.5mm, flow rates in between 1 and lOpL/min, and columns with 0.075-0.1 mm i.d. flow rates in the range of hundreds nL/min. Special miniaturized pump systems are required to deliver accurately mobile phase at very low flow rates in isocratic LC. 

The purpose of an analytical method is the deliverance of a qualitative and/or quantitative result with an acceptable uncertainty level. Therefore, theoretically, validation boils down to measuring uncertainty . In practice, method validation is done by evaluating a series of method performance characteristics, such as precision, trueness, selectivity/specificity, linearity, operating range, recovery, LOD, limit of quantification (LOQ), sensitivity, ruggedness/robustness, and applicability. Calibration and traceability have been mentioned also as performance characteristics of a method [2, 4]. To these performance parameters, MU can be added, although MU is a key indicator for both fitness for purpose of a method and constant reliability of analytical results achieved in a laboratory (IQC). MU is a comprehensive parameter covering all sources of error and thus more than method validation alone. 

The main significance of the terminal velocity lies in the fact that it defines the minimum gas velocity requested. The particle enters the system at Point 1 at zero velocity. If a gas velocity is employed so that u, < uh the particle cannot get into but drops out of the system if the gas velocity makes the relative velocity equal the terminal velocity, i.e., u, = it, the particle will move with a constant velocity of zero with respect to the ground, and so will remain at Point 1 while if the gas velocity makes the relative velocity greater than the terminal velocity, i.e., u,> it, the particle will be accelerated by the gas flow to the terminal velocity and will then move towards Point 2 at that velocity. Therefore, the terminal velocity is necessary for the determination of the operational range of the gas flow velocity for a specific vertical gas-solid impinging stream system. 

Octane response with increase in WAIT at identical pressure and WHSV are shown in Fig.3. An increase of about 12°C in WAIT is needed 10 attain an increase of 7 units in RONC. Fig.4 shows that at 24 kg/cm2 constant pressure and 88 octane severity, an increase of WHSV by 1 in the operational range required WAIT to be increased by 8°C,... 

These are total-recycle processes operating with an unconvened product recirculation loop at nearly constant pressure ranging between 15 and 20.10 absolute. 

Resistivity measurements were conducted on a number of representative insecticides selected from several major formulation categories as listed in Table I. Readings were taken at room temperature (=20 0) and 1000 Hz using a dip-type conductivity cell (0.10 cm constant) operated in conjunction with an autobalance digital Impedance meter. All test liquids were measured at 16 dilution ratios (-c.e., distilled water commercial formulation) ranging from 0 1 to 80 1 on a volume basis. 

For the RDE, the operating range of rotation frequency is between approximately 1 and 50 Hz and a typical radius is 0.25 cm. Dimensionless rate constants were interpolated from working curves generated from a fully implicit simulation using preconditioned Krylov subspace methods (Alden, unpublished work). 

Analysis of various tj s of industrial classifiers has led to the observation that the sharpness index is essentially constemt for a classifier (with a fixed geometrical configuration) over its normal operating range. Assuming that bypass is minimal, only two things affect the size distribution of the fine stream the size distribution of the feed and the cut size. Hence, if the size distribution of the feed is constant, only the cut size (c 5o) will affect the size distribution of the fines. Bypass can be minimized by proper design and operation of the classifier. 

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