Radiation Cerenkov

Cerenkov radiation accounts for a very minor part of the energy loss of fast electrons. Its main importance is for monitoring purposes and establishment of a reference time, since it is produced almost instantaneously with the passage of the particle. Katsumura et al. (1985) have observed a very fast rise of solute fluorescence attributable to the Cerenkov effect the G value for this process is estimated to be -0.02. 

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Carbon, analysis, 217, 318, 319 Carbon brushes, examination by x-ray absorptiometry, 97 Cathode follower, 60 Cauchois arrangement, 119, 120, 123 Caustic circle, 119, 120 Cells for liquids, 191, 194 Cements, analysis in Applied Research Laboratories PXQ, 260, 261 Ceramics, analysis by x-ray emission spectrography, 222-224 Cerenkov radiation, 43 Cesium, determination by x-ray emission spectrography, 328 Characteristic-line generator of Eng-strom, 144... 

Figure 11.4 Analysis of in vitro synthesized RNAs. 32P-Radiolabeled RNAs (48 nucleotides) capped with m7Gp3G (A and C) or m27,3 °Gp3G (B and D) were digested with either RNase T2 (A and C) or RNase T2 plus tobacco acid pyrophosphatase (TAP) (B and D) followed by anion-exchange HPLC on a Partisil 10SAX/25 column as described in the text. Fractions of 1 ml were collected, and the Cerenkov radiation was determined. The elution times of the following standard compounds, detected by ultraviolet (UV) absorption, are indicated with arrows 3,-CMP (Cp), S UMP (Up), 37-AMP (Ap), 3 -GMP (Gp), 3, 5 -m7GDP (pm7Gp), 3, 5 -GDP (pGp), 5 -GDP (p2G), 5 -GTP (p3G), and guanosine-SCtetraphosphate (P4G).

Jelly, J.V. (1958), Cerenkov Radiation and Its Application, Pergamon, Elmsford, NY. 

Cerenkov radiation emission of blue hght by particles moving faster than light in a medinm other than the vacuum (note that in a medinm with refrachve index n, hght moves with speed v = cjn)... 

The examples for radioactive labeling by phosphorus-32 ( P) and iodine-125 ( 1) in this chapter were chosen for two reasons on one hand, they are relatively easy to do, and on the other hand, the measurement of radioactivity is simple. is counted in water in a liquid scintillation counter by measuring the Cerenkov radiation and is measured in a gamma counter. Both isotopes may be detected also by autoradiography. A further advantage of both isotopes is their short half-life, which eases the disposal of nuclear waste. 

The jitter between the laser pulse and the electron pulse was estimated from the measurement using a streak camera (C1370, Hamamatsu Photonics Co. Ltd.), because the jitter is one of important factors that decide the time resolution of the pulse radiolysis. The jitter was several picoseconds. To avoid effects of the jitter on the time resolution, a jitter compensation system was designed [74]. The time interval between the electron pulse (Cerenkov light) and the laser pulse was measured by the streak camera at every shot. The Cerenkov radiation was induced by the electron pulse in air at the end of the beam line. The laser pulse was separated from the analyzing light by a half mirror. The precious time interval could be... 

Jonah et al. [178] found that the fluorescence emitted by 9,10-diphenyl-anthracene (or by p-terphenyl) in cyclohexane solution after photostimulation with Cerenkov radiation both grew-in and decayed more rapidly than when the solution was pulse-radiolysed (see Fig. 34). The delay in the formation of the aromatic excited state ( 0.5 ns) was attributed to the slowness of charge capture and of diffusion together of ions to form an excited state (Sect. 3.4). 

Ref J.V.Jelley, "Cerenkov Radiation and Its Applications", published for the United Kingdom Atomic Energy Authority, Pergamon Press, NY (1958)... 

Another mechanism for electron energy loss in matter is the emission of Cerenkov radiation. When a beam of fast moving charged particles with a velocity... 

Particles of kinetic energy 400 MeV are incident on a medium of index of refraction of 1.888. One observes Cerenkov radiation with an opening angle of 0 = cos 1(0.55). What are the particles ... 

A charged particle emits Vavilov-Cerenkov radiation (VCR) when its velocity becomes greater than the speed of light in the medium, that is, when v > dn where nr is the refractive index of the medium. This is so when the energy of the particle is sufficiently high—for electrons in water it must be >270 keV. And though the contribution of VCR to the energy losses is small, it can nevertheless be essential in photosensitive media (see Section VIII.C). 

When high-energy electrons pass through a dense medium such as water, they lose a fraction of their energy as Cerenkov radiation (Redpath et al. 1981 Myasnik et al. 1980). With DNA or cells y-irradiated in aqueous solution the UV part of the Cerenkov radiation causes the typical UV-induced DNA damage,... 

The enzymatic radioassay method for the analysis of acetylcholine and choline in brain tissue has been reported by Reid et al. [210]. The method describes the determination of nanogram amounts of acetylcholine and choline in as little as 10 mg of brain tissue, involves isolation of acetylcholine by high-voltage paper electrophoresis, alkaline hydrolysis of acetylcholine to choline, and conversion of this into [32P]-phosphoryl choline in the presence of choline kinase and [y32P] ATP. The labeled derivative is isolated by column chromatography on Bio-Rad AG1-X8 resin, using Tris buffer solution as the eluent. Cerenkov radiation from 32P is counted (at 33% efficiency) in a liquid scintillation spectrometer. The amount of phosphorylcholine is proportional to the amount of choline over the range of 0.08-8.25 nmol. 

Elrick, R.H., Parker, R.P. The use of Cerenkov radiation in the measurement of beta-emitting radionuclides. Appl. Radial. Isot. 19, 263-271 (1968)... 

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