نتایج جستجو برای: inductive ionization process
تعداد نتایج: 1362662 فیلتر نتایج به سال:
The nonlinear absorption mechanisms of neon atoms to intense, femtosecond kilovolt x rays are investigated. The production of Ne(9+) is observed at x-ray frequencies below the Ne(8+), 1s(2) absorption edge and demonstrates a clear quadratic dependence on fluence. Theoretical analysis shows that the production is a combination of the two-photon ionization of Ne(8+) ground state and a high-order ...
High precision photoelectron energy and angular distributions in helium and neon atoms for a broad intensity range reflect the change in the continuum dynamics that occurs as the ionization process evolves into the pure tunneling regime. Elastic rescattering of the laser-driven free electron from its parent ion core leaves a distinct signature on the spectra, providing a direct quantitative tes...
The dissociation constants for the carboxyl group of a series of glycine (N-acyl)-conjugated and unconjugated bile acids were determined by potentiometric titration using dimethylsulfoxide-water and methanol-water mixtures of varying proportions. The pKa values in water were calculated by extrapolating the experimental values determined in different mole fractions of the organic solvent mixture...
Mass spectrometry has been regarded as one of the most valuable analytical instruments since any compound has its intrinsic mass value. However, mass spectrometry can only be used to measure the mass-tocharge ratio (m/z) of a charged particle. Therefore, ionization process is usually needed unless the particle to be measured has an intrinsic charge. Nevertheless, the ionization efficiency is us...
The four-particle process of proton-helium transfer ionization has been studied using cold target recoil ion momentum spectroscopy to measure the momenta of all three particles in the final state. Most of the electrons are emitted in the H0 scattering plane and in the backward direction. The final state momentum distributions show discrete structures very different from those expected for uncor...
Multiple electron processes occur widely in atoms, molecules, clusters, and condensed matters when they are interacting with energetic particles or intense laser fields. Direct multielectron processes (DMEP) are the most complicated among the general multiple electron processes and are the most difficult to describe theoretically. In this work, a unified and accurate theoretical formalism is pr...
Proteomic analysis offers great diagnostic relevance, because unlike DNA, different cells in an organism express different proteins. In fact, the cellular proteome can vary as a function of time or in response to stimuli. Beyond amino acid sequence, protein function depends on chemical modifications known as posttranslational modifications (PTMs) that serve as “switches” and “signals” that acti...
We have measured the double-to-single photoionization ratio of atomic lithium and beryllium using the ion time-of-flight method. The photon beam of the PGM undulator beam line ionizes the vaporized target atoms. The ions created are extracted by a pulsed electric field across the interaction region and are detected by a Z-stack of micro-channel plates [1]. In the figure shown above, we compare ...
background: absolute dosimetry of external beam radiotherapy is carried out by the use of ionization chambers. these chambers must be calibrated at a standard dosimetry laboratory before any use in clinical dosimetry. the secondary standard dosimetry laboratory of iran (ssdl) has the duty of calibrating the ionization chambers used in radiotherapy centers in iran. materials and methods: the pre...
Bell’s palsy is an idiopathic peripheral nerve palsy involving the facial nerve. It accounts for 60 to 75% of all cases of unilateral facial paralysis. The main mechanisms to induce BP remain unclear, but infection, ischemic condition and immunodeficiency may contribute to the development of Bell’s palsy. Accumulating evidence has shown several factors can trigger the reactivation of latent...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید