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101.
Material ablation and plasma plume expansion study from Fe and graphite targets in Ar gas atmosphere
S. Mahmood R. S. Rawat S. V. Springham T. L. Tan P. Lee 《Applied Physics A: Materials Science & Processing》2010,101(4):695-699
Study of expansion dynamics of pulsed-laser ablation plasmas from Fe and graphite targets is presented. A 532 nm Q-switched
Nd:YAG laser with fluence of 30 J cm−2 is used to ablate the Fe and graphite targets in various Ar ambient gas pressures. Plasma ablation parameters for the two
target materials are estimated using snow-plow and shock-wave models, which show that the laser beam energy deposited to ablated
species remains at 70% for both targets at all ambient pressures. The plume splitting was observed, more prominently, for
Fe plasma as it moves faster compared to graphite plasma. The difference in plasma plume fronts’ speeds for different targets
was attributed to the significant difference in mass of the ablated plasma for two targets, as estimated from simulation results. 相似文献
102.
103.
[reaction: see text] Synthesis and characterization of core-modified [26]hexaphyrin (1.1.1.1.0.0). A meso aryl rubyrin isomer and a new 54pi-modified dodecaphyrin are reported. 相似文献
104.
[structure: see text] Two-photon absorption (TPA) cross-section values for a series of 22pi smaragdyrins bearing phenylacetylenylphenyl and [(phenylacetylenyl)phenylacetylenyl]phenyl meso links and their Rh(I) derivatives are reported. 相似文献
105.
Actinide dioxides (ThO 2 , UO 2 , Pu 2 etc.) compounds have the CaF 2 -type structure at ambient pressure and temperature. Under high pressure, they exist in the PbCl 2 -type structure, belonging to space group Pnma [1]. We have studied crystal structures under high pressure in actinide dioxides by means of first-principles self-consistent total-energy calculations with the non-local Perdew, Burke and Ernzerhof (PBE) exchange correlation using the full-potential linear-muffin-tin-orbital (FPLMTO) method. The atomic equilibrium volume, bulk modulus and transition pressure for actinide dioxides were calculated, covering the full pressure range for which the mentioned experiments have been done [2]. 相似文献
106.
Ijaz Ahmad Khan Syed Anwaar Hussain Amjad Farid Ali Hussnain Zeshan Adeel Umar Rajdeep Singh Rawat 《辐射效应与固体损伤》2013,168(11-12):929-943
ABSTRACTCrystalline silicon oxy-nitride (SiON) composite films are deposited on Si substrate for multiple (5, 15, 25 and 50) focus shots (FS) by plasma focus device. The X-rays diffraction patterns reveal the development of various diffraction peaks related to Si, Si3N4, and SiO2 phases which confirms the formation of SiON composite film. The intensity of Si3N4 (1 0 2) plane is linearly increased with the increase of FS. The Si3N4 (1 0 2) phase does not nucleate for 5 FS. Raman analysis confirms the formation of β–Si–N phase. Raman and Fourier transform infrared spectroscopy analysis reveals that the strength of chemical bonds like Si–N, Si–O formed during the deposition process of SiON composite films is associated with the bonds intensity which in turn depends on the number of FS. The field emission scanning electron microscopic analysis reveals that the surface morphology like size, shape and distribution of micro/nano-dimensional particles, film compactness and the formation of micro-rods, micro-teethes and micro-tubes of SiON composite films is entirely associated with the rise in substrate surface transient temperature which in turn depends on the increasing number of FS. The EDX spectrum confirms the presence of Si (22.5?±?4.7 at. %), N (13.4?±?4.5 at. %) and O (54.7?±?11.3 at. %) in the SiON composite film. The thickness of SiON composite film deposited for 50 FS is found to ~15.47?µm. 相似文献
107.
Retraction: Gairola, SP, Gairola, P, Shah, SK, Gupta, R. EMI shielding effectiveness of expanded graphite and reduced graphene oxide. J. Chin. Chem. Soc. 2018. https://doi.org/10.1002/jccs.201800189 . The above article, published online on 1 October 2018 in Wiley Online Library ( https://onlinelibrary.wiley.com ), has been retracted by agreement between the corresponding author, the journal's Editor‐in‐Chief, Dr. Yu‐Tai Tao, the Chemical Society Located in Taipei, and Wiley‐VCH Verlag GmbH & Co. KGaA. The retraction has been agreed due to several images across Figures 1, 2 and 3 within the article having been duplicated from other publications. The corresponding author apologizes for the inconvenience caused. 相似文献
108.
S.G. Rajeev 《Annals of Physics》2008,323(11):2654-2661
We solve exactly the classical non-relativistic Landau-Lifshitz equations of motion for a charged particle moving in a Coulomb potential, including radiation damping. The general solution involves the Painlevè transcendent of type II. It confirms our physical intuition that a negatively charged classical particle will spiral into the nucleus, supporting the validity of the Landau-Lifshitz equation. 相似文献
109.
Hamid Latif M. Shahid Rafique R.S. Rawat Shahzad Naseem 《Applied Surface Science》2008,254(22):7505-7511
In the paper an attempt has been made to use the laser-induced plasma as an X-ray source for the growth of nanostructures on the surface of gold. For this purpose, an Nd:YAG laser operated at second harmonics (λ = 532 nm, E = 400 mJ) is used to produce plasma from analytical grade 5N pure Al, Cu and W targets. An analytical grade (5N pure) gold substrate was irradiated by X-rays generated from Al, Cu and W plasma under the vacuum ∼10−4 Torr. The surface was analyzed by two techniques, XRD and AFM. The aberrations in the XRD peaks show that there are significant structural changes in the exposed gold, in terms of decreased reflection intensities, increased dislocation line density, changes in the d-spacing and disturbance in the periodicity of the planes. AFM used to explore the topography of the irradiated gold reveals that regardless of the source, nm sized hillocks have been produced on the gold surface. The roughness of the surface has increased due to the growth of these hillocks. 相似文献
110.