Plasma laser irradiated

Other topics recently studied by XPS include the effects of thermal treatment on the morphology and adhesion of the interface between Au and the polymer trimethylcy-clohexane-polycarbonate [2.72] the composition of the surfaces and interfaces of plasma-modified Cu-PTFE and Au-PTFE, and the surface structure and the improvement of adhesion [2.73] the influence of excimer laser irradiation of the polymer on the adhesion of metallic overlayers [2.74] and the behavior of the Co-rich binder phase of WC-Co hard metal and diamond deposition on it [2.75]. 

At low temperatures a pure semiconductor is a perfect insulator with no free carriers. Upon laser irradiation at a frequency greater than the semiconducting band gap, a high density of electron-hole pairs can be excited which, at liquid-helium temperatures, condense into small droplets of electron-hole plasma. These electron-hole (e-h) droplets have been discussed thoroughly in a dedicated volume of Solid State Physics that contains reviews of theoretical aspects (Rice, 1977) and experiments (Hensel et al., 1977). 

Figure 21-26 Emission from a plasma produced by laser irradiation of the high-temperature superconductor YBCI2CU3O7. Solid is vaporized by the laser and excited atoms and molecules such as YO emit light at characteristic wavelengths. [From w.a. warmer. "Plasma Emission from Laser Ablation of YBa2Cuj07." Appf. Phys. Lett. 1988, 52.2171]...

We have heard several papers on the reactions of coal or coal volatiles under conditions of very high energy input (in plasmas, laser irradiation, etc.). Potentially useful yields of valuable chemical raw materials result. The work therefore appears to be a new variety of cook-book preparative chemistry in which new and highly active species are involved as intermediates, and it is not easy for the ordinary chemist to visualize what goes on and what these intermediates are. Would any of the authors care to comment ... 

Robert A. Friedel To Dr. Sharkey s remarks on mass spectroscopy I would like to add a few pertinent comments on other types of spectroscopy which would be applicable to the study of species obtained from coal subjected to plasma, laser irradiation, and similar high energy processes. 

At suitably high laser irradiances at the solid surface, a plasma is formed as mentioned above. With properly chosen irradiation parameters, this plasma shows features, comparable to those of HF-spark sources, commonly used in mass spectrometry of inorganic solid samples. From results, reported in the literature (1, 2, 3), it can be deduced that the laser source may offer some advantages over classical spark sources with respect to sample preparation (nonconductors), reproducibility, collection efficiency and uniformity of elemental sensitivity factors. The laser in addition... 

At laser irradiances of typically about 10 Wcm and above, dense plasmas are formed from any solid sample, as is well documented by the large number of laser fusion experiments. In this mode of operation, energy is deposited into the solid during the initial... 

In this study, in order to better understand the fundamentals of the laser-cluster interaction, we have carried out systematic investigations of the properties of X-ray radiation from high-density and high-temperature cluster plasma created by the action of superintense laser irradiation. The interrelationship between the X-ray radiation properties and ion kinetic energies has been examined for the first time via simultaneous measurements of X-ray radiation spectra and ion energy spectra. The time scale and mechanism of the X-ray emission process are discussed here based on a time-dependent plasma kinetics model. Moreover, in order to demonstrate the practical capabilities of the X-rays thus produced, pulse X-ray diffraction from an Si crystal using this source has been examined. 

Junkel-Vives GC, Abdallah Jr. J, Blasco F, Dorchies F, Caillaud T, Bonte C, Stenz C, Salin F, Faenov AYa, Magunov AI, Pikuz TA, Skobelev IYu (2002) Evidence of supercritical density in 45-fs-laser-irradiated Ar-cluster plasmas. Phys. Rev. A 66 0332041-0332045... 

Other Methods Examples for other methods include co-casting of a hydrophobic and a hydrophilic polymer that contains amine, imine, hydroxyl, or carboxyl groups [61,89] surface modification by oxidation with ozone or by exposure to an electron or ion-beam ultrasonic etching and UV or laser irradiation [90-92]. A variety of functional groups have been also introduced onto the membrane surfaces by applying the gas discharge techniques (plasma treatment) operated at low or ambient pressure [93,94]. 

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