Q-factor

Fig.4. CCF dependences on loaded probe vibrator Q - factor for s(t) type (left) and q(t) signals. Q, = Q...

The mass balance relationships for the feed plate, the plates in the stripping section, of the column and for the reboiler must, however, be modified, owing to the continuous feed to the column and the continuous withdrawal of bottom product from the reboiler. The feed is defined by its mass flow rate, F, its composition xp and the thermal quality or q-factor, q. The column bottom product is defined by its mass flow rate, W, and composition, xw and is controlled to maintain constant liquid level in the reboiler. 

Ma L.Q. Factor influencing the effectiveness and stability of aqueous lead immobilization by hydroxyapatite. J Environ Qual 1996 25 1420-1429. 

Damping is often expressed in terms of quantities conveniently obtained with the type of instrument used. Since there are so many kinds of instruments, there are many damping terms in common use, such as the logarithmic decrement A, the half-width of a resonance peak, the half-power width of a resonance peak, the Q factor, specific damping capacity i <, the resilience R, and decibels of damping dB. 

Furthermore, each Q factor in equation 6.5-18 can be further factored for each individual mode, if the motions are independent for example,... 

For an RF electric field sensor, bandwidth (speed) is another important requirement. The speed of a resonator is determined by the cavity ring down time r = QX/c. As in any devices using resonating structures, a trade off between sensitivity (which increases with Q) and speed (which decreases when Q increases) has to be made. At the wavelength of 1.55 pm, Q factors of 104 and 106 translates to a sensor bandwidths of 20 GHz and 200 MHz, respectively. 

Fig. 8.11 Overall sensitivity as a function of W and R0 using (a) homogeneous and (b) surface sensing. The simulation illustrates that higher sensitivity requires smaller W but has little depen dence on Rc. Q factor is calculated and plotted in (c). Reprinted from Ref. 45 with permission. 2008 Institute of Electrical and Electronics Engineers...

We have studied, theoretically and experimentally, the characteristics of a novel class of lasers that are based on radial Bragg reflectors. Lasing action with low threshold levels are demonstrated at room temperature under pulsed optical pumping. The observed Q factors are in the order of several thousands. The unique characteristics on these lasers make them promising candidates for numerous applications in telecommunications, sensing, and basic research. 

Fig. 13.21 Variation of the Q factor in response to periodic change of the concentration of D20 in H20. Reprinted from Ref. 47 with permission. 2008 Optical Society of America...

These preliminary experimental results illustrate the power of the OFRR to detect specifically biomolecules while using low-cost photonics and simple protocols. The OFRR is a label-free Rl-based sensor, and thus it avoids the extra steps and costly photonics of fluorescence-based techniques. Even compared with other Rl-based techniques, such as SPR, the OFRR is able to use low-cost simple photonics because of its high Q-factor and thus minimal bandwidth requirements. Additionally, the sensor is inherently integrated into the microfluidic sample delivery channel. 

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