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ionisation of Rydberg hydrogen atom near a metal surface by short pulse laser

Chinese Physics B 2010年第11期19卷 318-322页

作者：汪磊杨海峰柳晓军刘红平 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of Sciences

In the ionisation of Rydberg hydrogen atoms near a metal surface, the electron will escape from the nucleus and arrive at the detector in a time sequence. This probability flux train relies on the initial electron wave packet irradiated by the laser pulse. For simplicity, the laser pulse is usually simplified to a delta function in energy domain, resulting in a sharp initial arrival time with an exponentially decaying tail at the detector. Actually and semiclassically, the initial outgoing wave should be modeled as an ensemble of trajectories propagating away from the atomic core in all directions with a range of launch times and a range of energies. In this case, each pulse in the pulse train is averaged out rather than a sharp profile. We examine how energy and time averaging of the electron wave packet affects the resolution of escaping electron pulses and study the energy dependence of the arrival time for each pulse in the ionisation train. An optimization condition for the laser pulse shape to generate narrow ionisation electron pulse in the train is obtained. The ionisation rates with various excitation energy are calculated also, which show the excitation to higher N Rydberg states will narrow the electron pulse as well.

关键词： Rydberg hydrogen ionisation trajectory

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Qualitative and Quantitative Assessment of Petroleum Contaminants in Soils under Tropical Weather Conditions

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American Journal of Analytical Chemistry 2019年第3期10卷 112-125页

作者： Imeh Okop Krishna Persaud School of Chemical Engineering and Analytical Science The University of Manchester Manchester UK

GC-FID methods for the analysis of Petroleum hydrocarbons were developed and optimised. Contamination of soil from the Niger Delta was investigated about 40 days after crude oil spillage from the Shell Petroleum marginal well head. Soil samples and controls were collected at depths of 0 - 15 cm, 15 - 30 cm and 30 - 60 cm. Samples were analysed using gas chromatography fitted with a flame ionisation detector. Penetration and migration of C10-C26 and C26-C34 hydrocarbons through the soil layers were assessed by cluster analysis to determine the spatial distribution, penetration and similarity of these compounds over the contaminated area. The results also indicated elevated levels of total hydrocarbon contents when compared with the reference sites. Recommendations are made to carefully monitor and remediate the environment.

关键词： Oil Spill Petroleum Contaminated Soils Total Petroleum Hydrocarbon Gas Chromatography-Flame ionisation Detector (GC-FID) Analysis

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Electron—Proton Twins, Orderly Arranged in The Inside of Bioatoms

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Open Journal of Physical Chemistry 2012年第4期2卷 262-270页

作者： John C. Stavridis George Baltatzis Constantine N. Pattas Department of Mechanical Engineering Laboratory of Applied Thermodynamics Polytechnic School of Thessaloniki Thessaloniki Greece Institute of Biomedical Research & Biotechnology Athens Greece

In the present study the first 20 microatoms of the periodic table are named as bioatoms, since they are needed for biochemical functions and services to life itself. The rationale behind this project is the detailed analysis of the ionization energy of the electrons in the inside of the bioatoms and their orderly arrangement at specific positions. Such position of the electrons is harmonized with the succession of their energy values in their logarithmic curves. The compelling arrangement of each electron at a particular place would not be feasible in the absence of an energy offset, which is a proton. The latter would hold electrons on their proper position. These fundamental aspects of our project receive such strong support from the quantum theory, according to which it is the electromagnetic interaction between electrons and protons by the exchange of photons, which hold them together in the atoms. According to our proposed model, the protons of the aforementioned proton—electron twins, are distributed on distinct positions which are the junctions of a primary network, coupled with their electrons, in a secondary network. The geometry and distance of the protons, in the plexus, is constant and is calculated at 8, 42 ?. This was estimated by a mathematical analysis of the proposed model, as discussed further. Our study has shown that electrons in the specific positions are moving in a symmetrical oscillation in the length of a channel, in vacuum, under the Coulomb forces. Moreover, the chemical evidence suggests that electrons, in an atom, have their own separate orbit, and that these orbits are closely interrelated.

关键词： Bioatoms Proton Network ionisation Energy Helium

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The radial correlation of atomic electrons in (e,2e) reaction

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Journal of Harbin Institute of Technology(New Series) 2000年第S1期7卷 113-115页

作者： V.A.Knyr V.V.Nasyrov Khabarovsk State University of Technology Russia680035

We perform a research of the influence of atomic electrons correlation to some characteristics of the (e,2e) process on helium. The Hilleraas type J-matrix approach was used for numerical calculations.

关键词： correlation ionisation cross section three body atomic system Schr*idinger equation, J-matrix method, (e,2e) reaction.

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加速器质谱法测量99Tc

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质谱学报 2005年第Z1期26卷 69-70页

作者：彭博何明丁艳秋管永精武绍勇董克君李世红阮向东姜山中国原子能科学研究院核物理研究所北京102413 广西大学广西南宁530004

99Tc is a fission product, and it has high fission yield (6%) and very long half-life (2.1×105 a). With the movement of nucleus, the concentration of 99Tc is increasing in the circumstance. So it's important to measure the concentration of 99Tc in the circumstance, and accelerator mass spectrometry (AMS) might be the best method for 99Tc measurement. The 93Nb is used for AMS instrument normalization, sample matrix. And we used the difference of energy loss and deducting the isotope to measure the 99Tc in a series of standard samples. And the results show that the AMS is the feasible measurement method.

关键词： 99Tc accelerator mass spectrometry deduct the isotope gas ionisation detector

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