Continuous wave mode

Table I Influence of the beam focusing in the laser-graphitization of chlorinated PVC (continuous wave mode emission line at 488.1 nm of Ar+ laser)...

NMR spectra were obtained in continuous wave mode on a Varian T-60, and in the pulsed Fourier transform mode on a Varian HR-220 with Nicolet TT-100 Fourier transform accessory, a Nicolet NT-300 wide bore system, and a Bruker WM-500. 13C T1 data were obtained... 

In practical application, Raman sensors exclusively use frequency-stabilised laser sources to compensate for the low intensity of the Raman radiation. For Raman sensors, prevalently compact high-intensity external cavity laser diodes are used, operated in CW (continuous wave) mode. These diode lasers combine high intensity with the spectral stability required for Raman applications and are commercially available at various wavelengths. 

A magnetic resonance spectroscopic technique used for detect hyperfine interactions between electrons and nuclear spins. In its continuous-wave mode, the ESR signal intensity is measured as radio frequency is applied. In pulsed mode, pulses of radio frequency energy are applied, and the ESR signal is detected as a spin-echo. In either case, enhanced EPR signal strength occurs when the radio frequency is in resonance with the coupled nuclei. 

The NMR spectrum can be recorded in various ways. The earliest commercial NMR spectrometers operated in continuous-wave mode, in which the sample is irradiated at constant frequency v while the magnetic field is swept through a range of values. The rf power absorbed by the sample is recorded at each value of H. When the value of H satisfies the resonance condition, a peak appears in the spectrum. Newer instruments rely on Fourier transform (FT NMR) spectroscopy, in which a sample held in a fixed magnetic field is irradiated with a short, intense burst of... 

A simple differential saturation method has been proposed (63) in which the differential saturation effects are obtained at the same overall irradiation level due to an audio-frequency modulation of the resonance frequency in the continuous-wave mode of operation. This results in the appearance of sidebands in addition to the centre band of the spectrum. By a judicious selection of the modulation index, the saturation of signals in the sidebands may be made to amount to 10 — 0-1% of those in the centre band. The lineshape of such a combination of the centre band and the two closest sidebands may be adjusted to that corresponding to the function ... 

A. Temporary. Bums of the skin and cornea indicate that an infrared or ultraviolet laser could have been used. Significant retinal hemorrhage probably means that a pulsed laser in the visible or near-infrared portion of the spectrum has been employed. Isolated retinal bums without significant hemorrhage probably indicate the use of a visible laser in the continuous wave mode. At lower exposure levels, the visible laser can impair visual function for as long as the laser source is visible. When the laser exposure terminates, vision will recover to normal without observable changes in the structure of the eye. 

The quartz disk is used as the bottom plate of a cell culture vessel and is moimted in a temperature controlled crystal holder (37 °C). The surface electrodes on either side of the quartz are connected to an impedance analyzer (Solatron Instruments, SI-1260) operating in continuous wave mode. The frequency-dependent complex impedance Z(J) returned by the impedance analyzer is expressed as magnitude of impedance Z (f) and phase shift between voltage and current (f). The raw data is analyzed by the well-known Butterworth-Van Dyke (BVD) equivalent circuit with the liunped impedance elements Co, Rq, iq, Cq and Zl. Rq, Lq and Cq represent the piezoelectric properties of the unperturbed resonator itself, whereas Co summarizes its dielectric properties and all parasitic contributions arising from contacts and wiring. The load material in contact with the resonator surface is represented by the complex impedance Zl. As long as the resonator is not loaded too... 

One can argue that aliphatic plasma polymers from ethylene or propylene produced in the continuous-wave mode have significant structural anomalies in comparison with the respective classical products [24] and therefore they should increase the adhesion strength rather than keeping it at a constant (low) level. As seen in this work, the structural anomalies of aliphatic layers were minimized by the use of the pulsed plasma technique. This is demonstrated by the... 

In the early 1980s, clinical echocardiography was performed with a sector scanner, a stand-alone Doppler unit capable of a pulsed and continuous-wave mode operation, a spectral analyser with high temporal resolution and an in-house black box which allowed EKG display along with the spectra (Gramiak and Holen 1984). Due to the fact that small gas bubbles dissolve rapidly in blood, the next aim was the production of agents small enough to traverse the pulmonary capillary bed. 

The authors of this chapter conducted a recent study, which evaluated the efficacy of plasma treatment on a model wood substrate. In order to imderstand the effect of plasma treatment on wood-based fibers, clear pine wood veneers with an identical chemical composition was used as a model substrate. Plasma treatment was conducted using a custom built 13.56MHz inductively coupled plasma chamber in continuous wave mode (CW) and continuous wave mode plus pulse plasma mode [60]. During continuous wave mode the plasma is always on , so the formation of functional groups is accompanied by their destruction due to the continuous ion bombardment or surface ablation. During the pulse mode, the plasma source is on for a specific period and the plasma generated is similar to the continuous wave mode, where the plasma reactive species interact with the surface of the wood substrate. During the period when the... 

M.J. McCarthy and D.C. Hanna, Continuous-Wave Mode-Locked Singly Resonant Optical Parametric Oscillator Synchronously Pumped by a Laser-Diode-Pumped Nd-.YLF Laser , Opt. Lett. 17, 402 (1992). 

E.S. Wachmann, D.C. Edelstein, and C.L. Tang, Continuous-Wave Mode-Locked and Dispersion-Compensated Femtosecond Optical Parametric Oscillator , Opt. Lett. 15, 136 (1990). 

To operate an atom laser in a continuous-wave mode was not an easy problem, for this task could only be coped with by decreasing the losses and replenishing the condensate. This goal was achieved by Ghikkatur et al. (2002), who produced condensates in two different vacuum chambers. The condensate periodically produced in one of the chambers was fed to the other chamber to merge with the condensate contained therein. This procedure provided a permanent reservoir of condensed atoms. The continuous release of the condensate from the former chamber thus provided for the continuous-wave operation of the atom laser. 

For many years, all commercial NMR spectrometers operated in continuous wave mode. This type of operation required a sweep of the NMR frequency or the magnetic field over a fixed range to bring each nucleus into resonance one at a time. These scans for ipF NMR spectroscopy would take typically 500 s to avoid signal distortion. Since most NMR spectra consist of a few sharp peaks interspersed with long regions of noise, this was a very inefficient process. A fundamental paper by Ernst and Anderson in 1966 pointed out the favourable gain in efficiency that... 

Many types of laser are available, used for different applications. Common laser types available are CO2, Nd YAG, Nd glass, ruby and excimer. Depending on economics of process, pulsed and continuous wave modes are used. 

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