Frequency mixing

The methods available include enhanced fiushing, enhanced vertical mixing, altered mixing frequency, and food-web manipulation. 

Alpha activity is replaced by predominant low-voltage, mixed-frequency background activity sometimes with vertex sharp waves Slow Decreased from wake... 

In REM sleep, there is a low-amplitude, mixed-frequency electroencephalogram, increased electric and metabolic activity, increased cerebral blood flow, muscle atonia, poikilothermia, vivid dreaming, and fluctuations in respiratory and cardiac rate. 

Mixed-frequency deposition of the nitride is one possibility to adjust the stress in the deposited layer [122]. The ratio of the deposition times in the high-frequency (375 kHz) and low-frequency (187.5 kHz) plasma can be varied during the process. For the layer used here 95% high-frequency deposition time was chosen (Fig. 4.14e).The stress was measured on wafer-level with a thin-film stress analyzer. The stress value was determined by recording the curvature of the wafer after thin-film deposition. A tensile stress of 75 5 MPa was measured for the layer. 

The oxidation reactions were performed in a 200 cm glass reactor, equipped with gas distributer, condenser, thermometer, measuring and reference electrodes. The mixing frequency of the magnetic stirrer was 1500 min 75 mg Pt or 450 mg Pt-on-alumina catalyst was prereduced in nitrogen atmosphere at 60 °C with 3.67 g or 3.00 g 1-phenylethanol, respectively. The solvent composition was 35 cm water +... 

The quantity on the left is the Fourier component of the dipole moment induced by the optical field Max(w). These equations can be generalized to mixed frequency-dependent electric dipole, electric quadrupole, magnetic dipole properties, and similar equations can be written for the Fourier components of the permanent electric quadrupole, aj8(magnetic dipole, ma(co). For static Maxwell fields similar expansions yield effective (starred) properties, defined as derivatives of the electrostatic free energies. 

It is also possible to mix frequencies when fight beams differing in frequency are made to follow the same path through a non-linear medium. For example, if two waves with electric field components E1 sin(rn[ t) and E2 sin(co2t) follow the same path through a dielectric with the characteristic... 

The sections which follow outline the general multidimensional distribution theory. Applications of the theory are discussed to describe droplet size distributions and mixing frequencies in chemically equilibrated systems, the effects of droplet mixing on the extent of reaction, the analysis of mass transfer with and without chemical reaction, hydrocarbon fermentation, and emulsion polymerization. 

Whereis the reaction modulus,/ /(wrfo) w, is the residence frequency I is the dispersed-phase mixing modulus o i/cor co, is the dispersed-phase mixing frequency and /i(c) dc is the fraction of drops of concentration in the range c to c + dc. 

Stage 1 NREM Sleep. The first state of sleep (also called drowsy state). This is characterized by a 50%diminution of the a waves of wakefulness in the EEG and low amplitude, mixed frequency activities (in the range of 3-7 Hz) consisting of B and some j3 waves. The muscular tone in the EMG becomes slightly relaxed, and slow rolling eye movements (SEM) are observed in the EOG. The state of drowsiness quickly changes to definite sleep. 

L6 REM Sleep. This is characterized by rapid eye movements. The slow wave pattern in the EEG is desynchronized and changes to a low amplitude mixed frequency 6 including some a pattern and often displaying saw tooth waves. No sleep spindles are seen. The muscle tone below the chin is totally relaxed or abolished. 

In Eqs. (4.5) and (4.6), Sa, tp, and denote the production rate of species a, the composition space of scalar , and the SGS mixing frequency, respectively. The molecular diffusivity coefficient and the SGS diffusivity coefficient are denoted by D and Dt- The last term on the right-hand side (RHS) of Eq. (4.6) represents the effects of chemical reaction and is in a closed form. The second and the third terms on the RHS represent the effects of SGS mixing and SGS convection, respectively, and are modeled with closures similar to those used in Reynolds-Averaged Navier-Stokes/Probability Density Function (RANS/PDF) methods [4]. 

Let us consider a concrete example. In their system, tritium has a resonance at 107 MHz. In order to get to an IF of 200 MHz, a local oscillator frequency of 307 MHz is used. The main reason for doing this is that the mixing frequency at 307 MHz is higher than any frequency of interest so that it, or its harmonics, cannot possibly interfere with any part of the desired signal. 

Barbosa MJ, Janssen M, Ham N, et al Microalgae cultivation in air-lift reactors modeling biomass yield and growth rate as a function of mixing frequency, Biotechnol Bioeng... 

Out of various mixed frequencies, the information carrying fl-equency is the difference frequency. In order to separate it from the other frequencies available at the output of the mixer, a low pass filter is needed. It is expected that the difference frequency will be of the order of a few kHz only. In order to accommodate the default difference between the reference and sensor oscillator, the cutoff frequency of the filter has been kept at IMHz. A passive low pass filter of the form shown in Fig. 8 has been utilized for this purpose. This filter did not require any complicated design techniques. The components values have been chosen as per the formula ... 

This frequency mixing in suitable nonlinear mixing elements is the basis for building up a frequency chain from the Cs atomic beam frequency standard to the optical frequency of visible lasers. The optimum choice for the mixer depends on the spectral range covered by the mixed frequencies. When the output beams of two infrared lasers with known frequencies v and V2 are focused together with... 

The problem of spin polarization in successive differently coupled spin pairs is approached under very simplifying assumptions. The mixing frequencies Q (defined in /6/) are large compared to the inverse lifetime of the spin pair. Therefore, we can consider time independent relative populations on the eigenstates of each spin pair as well as on any other appropriate basis system. The transition probabilities for the electron transfer step follow the projection of the spin states in the first spin pair onto the spin states of the second pair. (A more rigorous treatment has been performed in the group of J. R. Norris.) A test of our analysis is that it yields the expression for the standard CIDEP result (see e.g. /8/) when the coupling in the second pair is set to zero. Fig. 1 shows a simulation of polarized transient X-band... 

Vacuum ultraviolet spectroscopic data from mixed frequency plasma (microwave and RF plasma at the same time, in the same reactor) show an increased vacuum ultraviolet radiation over what is found in either RF or microwave plasmas alone. This radiation will increase the rate of initiation of surface reactions on polymers, while the increased concentration of groimd-state free-radicals (from the microwave) will increase the rate of free-radical oxidation of the polymer once the reaction has been initiated. Therefore, there is a synergistic effect between the RF and the microwave excitation of the plasma. This effect, along with the effect of RF self-bias, helps explain the increased rates of reaction that have been reported for mixed frequency plasma [7]. 

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