Rotational Sources

Rotational noise comprises two mechanisms related to linear aerodynamic theory thickness noise caused by the displacement and reconnection of the air by the rotor blades loading noise due to the forces that the rotor blades exert on the air. For a fixed location of the rotor plane, these processes occur 

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Fig. 2. Schematic of the rotatable sources, crossed-beam machine. 

To implement the Doppler-selected TOF measurement, the initial relative velocity is arranged to be parallel to the propagation vector of the probe laser. This critical configuration can readily be achieved in this rotating sources machine.36 Under this configuration, each Doppler-sliced 2D distribution exhibits a cylindrical symmetry The slit in front of the TOF spectrometer allows only those products with a rather small vx to be detected. Hence, only the -distribution, obtained by the TOF measurement, is needed to completely characterize the Doppler-sliced 2D (vx — vy) distribution. 

Name Formula Melting point (° C) Rotation Source ... 

Antioxidants from Cereais, Oiiseeds, and Rotated Sources Seeds rich in oils are also abundant sources of various types of antioxidative compounds. Among these carotenoids, phenolic acids, and their derivatives, flavonoids, phytic acid, lignans, and tocopherols are predominantly found depending on the plant genera and species. Reviews by Wanasundara et al. (110) and Shukla et al. (111) discuss antioxidants of oilseeds and their products in detail. 

Fig. 7.11.17 Anisotropic magnetoresistance sensor principle for 360° rotation (source Bosch)...

The conventional way of scanning the angular distribution of the products is by means of using rotatable sources. The two sources are attached to a circular turntable and the point of intersection of the beams may be swept past the detector [6, 8]. 

A detailed description of the molecular beam apparatus used, the rotating source machine, is available elsewhere [10]. For the present discussion a general outline of the salient features will be given, referring to the schematic diagram in Fig. 3. The important parts of the rotating source machine are labeled with numbers in this diagram. 

Fig. 2.9 The horizontal cut view of the instrument that shows the driving mechanisms for the rotating detector and the rotating source. Reprinted with permission from Ref. [26]. 2005, American Institute of Physics...

Figure 11.12 Dependence of the heat capacity on temperature for an ideal gas. Cooling a hot gas leads to freezing out of degrees of freedom first electronic freedom, then vibrations, then rotations. Source ... 

Photo-induced sophisticated 3D motions of a LCE film laminated on a flexible polyethylene sheet, (a) Schematic illustration of a light-driven plastic motor and photographs of time profiles of the rotation. (Source Adapted with permission from Reference [116].)... 

The divergent shape of the beam provides facilities for magnification in the distances of the source to detector and of the sources to the axis of rotation, which used in conjunction with a microfocus x-ray source opens the way to high resolution. 

This research examines the feasibility of a technique based upon the CT principle using a microfocus X-ray source with an image intensifier while the examined object is being rotated The attainable enlargement is up to 200. The data to be processed is collected from the whole surface of the image intensifier by a frame grabber and noise suppression is performed. 

In a commercial CT system an X-ray source and a set of detectors rotate around the examined object Two main difficulties that typical CT method meets are challenged in this study ... 

The setup as seen in Figure 1 mainly consists of a Varian Linatron 3000A linear accelerator (LINAC) as radiation source, a rotational stage for sample manipulation, and a two-dimensional high-energy x-ray detector array consisting of four amorphous silicon area detectors Heimann RIS 256. The source to detector distance is 3.7 m. 

Other limitation for the spatial resolution can be found in the detector. A limited number of pixels in the camera array can be a reason for pure resolution in the case of a big field of view. For example, if field of view should be 10 by 10 nun with camera division 512x512 pixels the pixel size will be approximately 20 microns. To improve the relation of the field of view and the spatial resolution a mega-pixel sensor can be used. One more limitation for the spatial resolution is in mechanical movement (rotation) of the object, camera and source. In the case of a mechanical movement all displacements and rotations should be done with accuracy better than the spatial resolution in any tested place of the object. In the case of big-size assemblies and PCB s it is difficult to avoid vibrations, axle play and object non-planarity during testing. 

During testing a depth resolution of 50-80 micron and a lateral resolution of 20-40 micron was achieved. The spatial resolution was limited not mainly hy source or camera properties, but by the accuracy of compensation of the instrumental errors in the object movements and misalignments. According to this results a mote precision object rotation system and mote stable specimen holding can do further improvements in the space resolution of microlaminography. 

The above three sources are a classic and comprehensive treatment of rotation, vibration, and electronic spectra of diatomic and polyatomic molecules. 

Waveguides are coimnonly used to transmit microwaves from the source to the resonator and subsequently to the receiver. For not-too-high-frequency radiation (<10 GHz) low-loss MW transmission can also be achieved usmg strip-lines and coaxial cables. At the output of a klystron an isolator is often used to prevent back-reflected microwaves to perturb the on-resonant klystron mode. An isolator is a microwave-ferrite device that pemiits the transmission of microwaves in one direction and strongly attenuates their propagation in the other direction. The prmciple of this device involves the Faraday effect, that is, the rotation of the polarization... 

Figure B2.1.1 Femtosecond light source based on an amplified titanium-sapphire laser and an optical parametric amplifier. Symbols used P, Brewster dispersing prism X, titanium-sapphire crystal OC, output coupler B, acousto-optic pulse selector (Bragg cell) FR, Faraday rotator and polarizer assembly DG, diffraction grating BBO, p-barium borate nonlinear crystal.

Figure B2.3.7. Schematic apparatus of crossed molecular beam apparatus with synclirotron photoionization mass spectrometric detection of the products [12], To vary the scattering angle, the beam source assembly is rotated in the plane of the detector. (By pemrission from AIP.)...

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