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91.
In this study, a coupled-channel (CC) analysis of the elastic and the inelastic scattering of 20.4 MeV polarized protons from a 64Zn target leading to the deformed 2 + , 3−, 22+2_2^+ states was performed. The CC potential parameters and the deformation parameters of the excited states corresponding to the best fit to the experimental differential cross-sections and the analysing powers data were determined. For 22+2_2^+ excited state, a mixed type was used and a good fit to the data was provided. The CC calculation results were compared to the pure distorted wave Born approximation (DWBA) calculation results which were calculated using the new parameters. All calculations were conducted using the computer code ECIS06.  相似文献   
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A 80???J, 6?fs, CEP-stable high-contrast injector is demonstrated. The device relies on standard pulse post-compression in hollow-core fiber followed by a temporal filter based on cross-polarized wave generation. Pulses with a Gaussian spectrum over 350?nm, centered at 750?nm, are generated. Temporal measurements show that the contrast of the few-cycle pulses is enhanced on a femtosecond and picosecond time scale. The carrier-envelope phase stability is preserved (0.3?rad RMS). These performances make the system an ideal seed laser for high-power, high-contrast OPCPA systems.  相似文献   
94.
The accelerated single electron transfer–degenerative chain transfer mediated living radical polymerization (SET–DTLRP) of vinyl chloride (VC) in H2O/tetrahydrofuran (THF) at 25 °C is reported. This process is catalyzed by sodium dithionite (Na2S2O4)‐sodium bicarbonate (NaHCO3). Electron transfer cocatalysts (ETC) 1,1′‐dialkyl‐4,4′‐bipyridinum dihalides or alkyl viologens were also employed in this polymerization. The resulting poly(vinyl chloride) (PVC) has a number‐average molecular weight (Mn) = 2,000–12,000, no detectable amounts of structural defects, and both active chloroiodomethyl and inactive chloromethyl chain ends. The molecular weight distribution of PVC obtained is Mw/Mn = 1.5. The surface active agents afford the final polymers as a powder and provide an acceleration of the rate of polymerization. The role of ETC is to accelerate the single electron transfer (SET) step, whereas THF enhances the degenerative chain transfer (DT) step. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6364–6374, 2004  相似文献   
95.
We have grown hematite (αFe 2 O 3) thin films on stainless steel and (001)-silicon single-crystal substrates by RF magnetron sputtering process in argon atmosphere at substrate temperatures from 400 to 800°C. Conversion Electron Mössbauer (CEM) spectra of the sample grown on stainless steel at 400°C exhibit values for hyperfine parameter characteristic of bulk hematite phase in the weak ferromagnetic state. Also, the relative line intensity ratio suggests that the magnetization vector of the polycrystalline film is aligned preferentially parallel to the surface. The X-ray diffraction (XRD) pattern of the polycrystalline thin film grown on steel substrates also corresponds to αFe 2 O 3. The samples were also analyzed by Atomic Force Microscopy (AFM), those grown on stainless steel reveal a morphology consisting of columnar grains with random orientation, given the inhomogeneity of the substrate surface.  相似文献   
96.
Conclusions PBI is a unique polymer for ion exchange/sorption or affinity chromatography. The excellent flow and ion exchange properties of PBI resins have been demonstrated by their applications for determinatiòn of urinary VMA and PBG. Furthermore, PBI was also applied successfully as an affinity chromatography medium for several enzymes with polymeric molecules as their substrates. These studies concluded that PBI polymer has versatile biochemical applications.
Biochemische Anwendung von Polybenzimidazol (PBI) als Ionenaustauscher und Sorbens
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