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91.
Electron impact single and double ionization cross sections of gallium have been calculated in the binary encounter approximation
using accurate expression for σΔ;E including exchange and interference as given by Vriens and Hartree-Fock velocity distributions for the target electrons throughout
the calculations. It is concluded that the ionization of 3d shell contributes partly to single ionization and partly to double
ionization. The results so obtained show reasonably good agreement with the experimental data. 相似文献
92.
93.
Two-color cross-correlation of fs-laser pulses by two-photon induced photoconductivity for near and far field optical measurements 总被引:1,自引:0,他引:1
Wolfgang Schade David L. Osborn Jan Preusser Stephen R. Leone 《Optics Communications》1998,150(1-6):27-32
Two-color two-photon induced photoconductivity in a GaAsP diffusion type photodiode is demonstrated by measuring femtosecond cross-correlation functions for widely separated wavelength pairs of 775 and 1300 nm. Results are obtained for a range of tunable wavelengths and average powers of the incident lasers by measuring the two-photon induced photocurrent as a function of the optical delay between the pulses. The temporal autocorrelation of femtosecond laser pulses in the near-field of a small diameter aluminum coated optical fiber tip is also obtained with the same photodiode method for single colors. 相似文献
94.
为研究使用不同形状光斑触发光导开关对光电导特性的影响,研制了12 mm间隙的半绝缘砷化镓光导开关,在不同的偏置电压下,使用波长为1 064 nm的不同能量的激光触发光导开关并进行了光电导测试。使用了不同形状的光斑(包括面状、线状和点状光斑)触发光导开关并进行了光电导特性的比较,讨论了触发光参数对光导开关特性的影响。对处于开关电极间不同位置的线状光斑触发特性进行了比较,结果显示,本征光电导和非本征光电导情况下光斑位置对光电流的影响正好相反。 相似文献
95.
Microstructure and strain films using in-plane grazing analysis of GaN epitaxial incidence x-ray diffraction 下载免费PDF全文
This paper investigates the major structural parameters, such as crystal quality and strain state of (001)-oriented GaN thin films grown on sapphire substrates by metalorganic chemical vapour deposition, using an in-plane grazing incidence x-ray diffraction technique. The results are analysed and compared with a complementary out-of-plane x- ray diffraction technique. The twist of the GaN mosaic structure is determined through the direct grazing incidence t of (100) reflection which agrees well with the result obtained by extrapolation method. The method for directly determining the in-plane lattice parameters of the GaN layers is also presented. Combined with the biaxial strain model, it derives the lattice parameters corresponding to fully relaxed GaN films. The GaN epilayers show an increasing residual compressive stress with increasing layer thickness when the two dimensional growth stage is established, reaching to a maximum level of-0.89 GPa. 相似文献
96.
97.
98.
Ksenia Shablinskaya Elena Murashova Zhanafiya Kurenbaeva Alexander Yaroslavtsev Yurii Seropegin Dariusz Kaczorowski 《ChemInform》2013,44(41):no-no
Ce4Ru3Ga3 (I) and La3Ru2Ga2 (II) are synthesized by arc melting of the elements under Ar followed by annealing (873 K, 30 d). 相似文献
99.
Indium phosphide sample was irradiated with 200?MeV Ag9+ ions for the fluence of 2?×?1013?ions?cm?2. The sample was chemically etched down up to 240?nm depth to investigate the distribution of defects at different regions. Raman scattering and glancing incidence X-ray diffraction spectra were recorded at different depths. The stress estimated from Raman shift was found to increase with depth up to 160?nm and thereafter it decreased and at a depth of 224?nm sample did not show any stress. Phonon coherence length estimated from the Phonon Confinement Model was found to vary between 43 and 18?nm with respect to depth. Glancing incidence X-ray diffraction results revealed the decrease in crystallite size from 16.12 to 1.00?nm in different depth regions. 相似文献
100.
Werner Uhl Frank Hengesbach Jennifer Isermann Meisam Soleimani Lina Schürmann Alexander Hepp Marcus Layh 《无机化学与普通化学杂志》2019,645(20):1205-1214
Hydrogallation of Me3Si–C≡C–NR'2 with R2Ga–H (R = tBu, CH2tBu, iBu) yielded Ga/N‐based active Lewis pairs, R2Ga–C(SiMe3)=C(H)–NR'2 ( 7 ). The Ga and N atoms adopt cis‐positions at the C=C bonds and show weak Ga–N interactions. tBu2GaH and Me3Si–C≡C–N(C2H4)2NMe afforded under exposure of daylight the trifunctional digallium(II) compound [MeN(C2H4)2N](H)C=C(SiMe3)Ga(tBu)–Ga(tBu)C(SiMe3)=C(H)[N(C2H4)2NMe] ( 8 ), which results from elimination of isobutene and H2 and Ga–Ga bond formation. 8 was selectively obtained from the ynamine and [tBu(H)Ga–Ga(H)tBu]2[HGatBu2]2. 7a (R = tBu; NR'2 = 2,6‐Me2NC5H8) and H8C4N–C≡N afforded the adduct tBu2Ga‐C(SiMe3)=C(H)(2,6‐Me2NC5H8) · N≡C–NC4H8 ( 11 ) with the nitrile bound to gallium. The analogous ALP with harder Al atoms yielded an adduct of the nitrile dimer or oligomers of the nitrile at room temperature. The reaction of 7a with Ph–N=C=O led to the insertion of two NCO groups into the Ga–Cvinyl bond to yield a GaOCNCN heterocycle with Ga bound to O and N atoms ( 12 ). 相似文献