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Irradiation susceptibility

Due to the composition of the weld consumables used, the SAWs had a higher level of impurity Cu than the other materials. In the USA, Cu had been recognised as an impurity element promoting greater irradiation susceptibility in steels and welds exposed in PWRs at higher irradiation temperatures and doses. In the UK, Fisher, Harbottle and Aldridge showed that the process of Cu precipitate nucleation and growth, which was... [Pg.164]

The NFS shear successfully processed irradiated LWR fuel between 1966 and 1972. Among the lessons learned were that the chute that channeled sheared fuel pieces to the dissolver basket was susceptible to bridging, the gag drives required a disproportionate amount of maintenance, and insufficient throat clearance led to jamming of chopped fuel. [Pg.207]

Susceptibility to radiation damage must be considered seriously if reference samples are to be calibrated for use in place of absolute systems. For the measurement of absolute C He, H) cross sections, films of polystyrene (CH) (which is relatively radiation hard) have been used successfiiUy, the RBS determination of carbon providing implied quantitation for the hydrogen present in the film. For a durable laboratory reference sample, however, there is much to recommend a known ion-implanted dose of H deep within Si or SiC, where the loss of hydrogen under room temperature irradiation will be neghgible. [Pg.498]

If infra-red heating or any other radiation curing method is employed, areas which are shaded from the rays or are outside the area of greatest flux density, cannot dry as hard as the fully irradiated surfaces, and may form weak spots susceptible to mechanical damage and consequent corrosion. [Pg.614]

Some established cell lines were derived from malignant tissue. Many of these cell lines can form tumors when injected into susceptible animals. Other established cell lines are not Uunorigenic. However, exposure to carcinogens, and irradiation can cause these cells to form tumors in susceptible animals. In addition, transformation can be caused by spontaneous mutations, by growth factors, and by viral (or oncogenic) transformation (Table 6). Malignant transformation is defined as consisting of the series of events that cause normal cells to develop the capacity to form tumors. [Pg.477]

Sum-frequency (SF) spectroscopy [1] has been used to achive vertical resolutions much better than the wavelength. Sum-frequency light is generated at an interface irradiated with infrared (IR) and visible light. The probability of sum-frequency generation is governed by a second-order susceptibility to be zero in any medium... [Pg.103]

For the application of QDs to three-dimensional biological imaging, a large two-photon absorption cross section is required to avoid cell damage by light irradiation. For application to optoelectronics, QDs should have a large nonlinear refractive index as well as fast response. Two-photon absorption and the optical Kerr effect of QDs are third-order nonlinear optical effects, which can be evaluated from the third-order nonlinear susceptibility, or the nonlinear refractive index, y, and the nonlinear absorption coefficient, p. Experimentally, third-order nonlinear optical parameters have been examined by four-wave mixing and Z-scan experiments. [Pg.156]

Fe(6-Mepy)2(py)tren] (004)2 Doped in PSS. Magnetic susceptibilities measured for a microcrystalline sample of the complex produce a magnetic moment value = 0.36 pg at 10 K and 0.61 pg at 150 K, followed by a gradual increase to Peff = 2.80 pe at 311 K [138]. Thus 26% of the complexes are in the HS state at 300 K if a magnetic moment of 5.1 Pe is assumed for the pure HS compound. On the other hand, the complex doped into a polystyrene sulfonate (PSS) film does not provide any evidence for a thermal population of the HS state up to 340 K as demonstrated by variable-temperature UV-VIS and Mossbauer spectra. In fact, all the complexes doped into the PSS film are in the LS state at temperatures below 340 K. However, if irradiated by a single pulse of a Q-switched Nd/YAG laser (532 mp), the complex is excited from the LS ground state to the HS J2 states via an intermediate MLCT state and the metal states. The subsequent back relaxation from the excited T2 state to the... [Pg.129]

The term nonlinear optical property refers to an optical property, which can be modified by exposing the material to intense light irradiation. In this section, we focus on the cascaded first- (/ 1 ) and third-order ( / ) susceptibilities describing nonlinear absorption (ESA and 2PA) and nonlinear refraction (n2) processes. Z-scan, pump-probe, and two-photon upconverted fluorescence techniques are among the most used experimental methods for determining optical nonlinearities. [Pg.119]

Some effects of irradiation on vitamins have been mentioned earlier. It appears that irradiation and heat treatment affect vitamins differendy. Apparendy, vitamins Br B6, B12 and folic acid decompose less under as high a radiation dose as 60 kGy than under autoclaving at 120°Cfor 20 minutes. On the other hand, vitamin C is much more sensitive to irradiation. Generally, the radiosensitive vitamins are also sensitive to light, heat, and oxygen. In fresh foods, the vitamins that are most susceptible to irradiation are A and E. There is also some decomposition of vitamins B, and C. Other vitamins are fairly stable under irradiation. However, for the most part, the vitamins are more susecptible to heat treatment than to irradiation. [Pg.382]

To analyze the second-order susceptibility, the symmetry of the films was first analyzed by measuring the intensities of the second-harmonic light. The sample was irradiated with polarized light from a Nd YAG laser incident at 45°, and the second-harmonic light emanating from the sample was detected while the sample was rotated around its surface normal. No variation in the second-harmonic intensity was observed as the sample was rotated, indicating... [Pg.565]

Pristane (2,6,10,14-tetramethylpentadecane) is a mineral oil known to induce arthritis, a disease also referred to as pristane-induced arthritis (PIA) [58], Susceptibility to PIA is MHC-haplotype dependent, in that DBA/1 (H2q) mice are susceptible whereas DBA/2 (H2d) are not, and is accompanied by a broad spectrum of autoantibodies, including anti-Rheuma Factor (RF), anti-collagen and antibodies to heat shock proteins (HSP). PIA is clearly immune dependent since nu/nu mice and irradiated mice do not develop PIA. PIA involves polyclonal T cell activation [59], particularly CD4+ cells [58], Intriguingly, mice can be protected from developing PIA by HSP65-specilic CD4+ Th2 cells [60],... [Pg.476]

Solid-liquid phase systems with no added solvent produce esters in high yield [e.g. 2, 3] and are particularly Useful when using less reactive alkyl halides [e.g. 15], for the preparation of sterically hindered esters [16], or where other basic sites within the molecule are susceptible to alkylation, e.g. anthranilic acid is converted into the esters with minimal A-alkylation and pyridine carboxylic acids do no undergo quat-emization [17]. Excellent yields of the esters in very short reaction times (2-7 minutes) are also obtained when the two-phase system is subjected to microwave irradiation [18]. Direct reaction of the carboxylic acids with 1,2-dichloroethane under reflux yields the chloroethyl ester [19], although generally higher yields of the esters are obtained under microwave conditions [20]. [Pg.87]


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See also in sourсe #XX -- [ Pg.33 ]




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