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Industrial Research on broadening of Slab in Continuous Casting Process

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Journal of Iron and Steel Research(International) 2010年第8期17卷 20-24页

作者： FU Jian-xun LI Jing-she ZHANG Hui ZHANG Xing-zhong School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Machinery and Electric Department University of JiaozuoJiaozuo 454000HenanChina National Engineering Research Center of Continuous Casting Technology Central Iron and Steel ResearchInstituteBeijing 100081China

In order to check the general existence of broadening of slab and the reasons of formation,the broadening of slab was investigated on the basis of several industrial manufactures of continuous casting.The results show that slab broadening commonly exists in the process of continuous casting.The causes of broadening were ruled out of the consideration of the change of mold size or the change of technical parameters.The results reveal that the broadening of slab probably results from the static pressure of molten steel and the force from driving rolls.At the same time,online observations of three grades of steel in the process of continuous casting reveal that the ratio of ultimate broadening of slab ranges from 1.27% to 3.00%,and even arrives at 4.4%.

关键词： continuous casting slab broadening industrial investigation

Temporal broadening of pulsed waves propagating through turbulent media

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Science China(Physics,Mechanics & Astronomy) 2003年第4期46卷 337-347页

作者：许正文吴健霍文平吴振森 School of Science Xidian UniversityXi'an 710071China National Key Laboratory of Electromagnetic EnvironmentChina Research Institute of Radiowave PropagationBeijing 102206China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationBeijing 102206China School of Science Xidian UniversityXi'an 710071China

Pulse signals, propagating through a turbulent medium such as the ionosphere, can be distorted by dispersion and scattering from both the background medium and irregularities embedded in. Thus, the mean square pulse width is changed, and temporal broadening is introduced. We carry out a study on the temporal broadening with theoretical analyses and numerical simulations by using an analytical solution of two-frequency mutual coherence function obtained recently by iteration. As a case of study, pulse broadening is investigated in detail in trans-ionospheric propagation. Results show that most contributions are mainly from the dispersion of the background ionosphere and scattering effects of electron density irregularities in most cases.

关键词： radio wave propagation, random media, pulse, mean square pulse width, temporal broadening

On-the-fly Doppler broadening method based on optimal doubleexponential formula

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Nuclear Science and Techniques 2017年第11期28卷 251-257页

作者： Rui Chen Li-Juan Hao Bin Wu Jing Song Li-Qin Hu Key Laboratory of Neutronics and Radiation Safety Institute of Nuclear Energy Safety Technology Chinese Academy of Sciences Hefei 230031 China University of Science and Technology of China Hefei 230027 China

As temperature changes constantly in nuclear reactor operation, on-the-fly Doppler broadening methods are commonly adopted for generating nuclear cross sections at various temperatures in neutron transport simulation. Among the existing methods, the widely used SIGMA1 approach is inefficient because it involves error function and Taylor series expansion. In this paper, we present a new on-the-fly Doppler broadening with optimal double-exponential formula based on SuperMC to improve efficiency with given accuracy. In this method, doubleexponential formula in 1/16 steps is used for broadening cross section at low energy, with both accuracy and efficiency. Meanwhile, the Gauss–Hermite quadrature of different orders is used for broadening cross section at resonance energy. The method can generate neutron cross section rapidly and precisely at the desired temperature.Typical nuclide cross sections and benchmarking tests are presented in detail.

关键词： On-the-fly Doppler broadening Cross section Double-exponential formula SuperMC

Zone broadening and Simulation of Migration Process of Peptides in Capillary Zone Electrophoresis

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Science China Chemistry 1994年第7期37卷 807-819页

作者：林炳承许旭罗国安 Dalian Institute of Chemical Physics Academia Sinica Department of Analytical Chemistry China Pharmaceutical University

The contributions of injection,detection,molecular diffusion and Joule heating to the zonebroadening in capillary zone electrophoresis (CZE) were evaluated theoretically.Approximate equations havebeen derived to calculate the total zone width in CZE.The theoretically calculated values from model formulaagree well with experimental ones.Based on the formula of the total variance,a mathematical expression tocalculate the column efficiency (the plate height) has been derived.The relationship between the column ef-ficiency and experimental conditions has been discussed.Combined in the method to estimate the migrationtime of peptides in CZE,the migration process of the peptides in the column of CZE has been simulated by the computer.

关键词： capillary zone electrophoresis mathematical calculation for zone broadening column efficiency peptides computer simulation

Theoretical investigation of the pressure broadening D1 and D2 lines of cesium atoms colliding with ground-state helium atoms

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Chinese Physics B 2019年第10期28卷 300-308页

作者： Moussaoui Abdelaziz Alioua Kamel Allouche Abdul-rahman Bouledroua Moncef Universite Cherif Messaidia B.P.1553Souk-Ahras 41000Algerie Laboratoire de Physique de la Matiere et du Rayonnement LPMR Universite Cherif MessaidiaB.P.1553Souk-Ahras 41000Algerie Universite Lyon 1 CNRSLASIM UMR5579bat.A.Kastler43 Bd du 11 novembre 1918F-69622 VilleurbanneFrance Laboratoire de Physique des Rayonnements LPR Universite Badji MokhtarB.P.12Annaba 23000Algerie

Full quantum mechanical calculations are performed to determine the broadening in the far wings of the cesium D1 and D2 line shapes arising from elastic collisions of Cs atom with inert helium atoms. The potential energy curves of the low-lying CsHe molecular states, as well as the related transition dipole moments, are carefully computed from ab initio methods based on state-averaged complete active space self-consistent field-multireference configuration interaction(SACASSCF-MRCI) calculations, involving the spin-orbit effect, and taking into account the Davidson and BSSE corrections.The absorption and emission reduced coefficients are determined in the temperature and wavelength ranges of 323-3000 K and 800-1000 nm, respectively. Both profiles of the absorption and the emission are dominated by the free-free transitions,and exhibit a satellite peak in the blue wing near the wavelength 825 nm, attributed to B^2Σ1/2^+→ X^2Σ1/2^+/transitions. The results are in good agreement with previous experimental and theoretical works.

关键词： absorption coefficient emission coefficient pressure broadening potential curves

Cesium atomic Doppler broadening thermometry for room temperature measurement

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Chinese Optics Letters 2019年第6期17卷 1-4页

作者：潘奕捷廖文汉王贺姚燕蔡晋辉屈继峰 Center for Advanced Measurement Science National Institute of MetrologyBeijing 100029China College of Metrology & Measurement Engineering China Jiliang UniversityHangzhou 310018China School of Optoelectronics Beijing Institute of TechnologyBeijing 100081China

Atomic Doppler broadening thermometry(DBT)is potentially an accurate and practical approach for thermodynamic temperature measurement.However,previous reported atomic DBT had a long acquisition time and had only been proved at the triple point of water,0℃,for the purpose of determination of the Boltzmann constant.This research implemented the cesium atomic DBT for fast room temperature measurement.The Cs^133 D1(6S^1/2→6p^1/2 transition)line was measured by direct laser absorption spectroscopy,and the quantity of thermal-induced linewidth broadening was precisely retrieved by the Voigt profile fitting algorithm.The preliminary results showed the proposed approach had a 4 min single-scan acquisition time and 0.2%reproducibility.It is expected that the atomic DBT could be used as an accurate,chip-scale,and calibration-free temperature sensor and standard.

关键词： Atomic Doppler broadening potentially an accurate sensor and standard

Spectroscopic measurement of Stark broadening parameter of the 636.2 nm Zn I-line

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Natural Science 2013年第4期5卷 501-507页

作者： Ashraf M. El Sherbini Abdel-Nasser Aboulfotouh Farid Rashid Sami H. Allam Ahmed M. Al-Kaoud Ashraf El Dakrouri Tharwat M. El Sherbini College of Applied Medical Sciences King Saud University Riyadh KSA Department of Laser and Opto-Electronic Engineering University of Technology Baghdad Iraq Department of Physics Collage of Science AL-Imam Muhammad Ibn Saud Islamic University (AIMSIU) Al Riyadh KSA Department of Physics Laboratory of Lasers and New Materials Faculty of Science Cairo University Giza Egypt

In this article we will present an attempt to measure the Stark broadening parameter of the Zn I-line at 636.23 nm utilizing the optical emission spectroscopy (OES) technique, taking into consideration the possibility of existence of self absorption. This method is standing on comparison of the Lorentzian FWHM and spectral line intensity of the unknown Stark broadening parameter line (Zn I-636.23 nm—in our case) to a well known Stark parameter line (e.g. Zn I-lines at 472.2, 481 and 468 nm) at a reference electron density of 2.7 × 1017 cm-3 and temperature of 1 eV. We have utilized the emission spectral data acquired from well diagnosed plasma produced by the interaction of Nd: YAG laser at wavelength of 1064 nm with ZnO nanomaterial target in open air. The results indicates that the Stark broadening of the Zn I-line at 636.23 nm is centered at 5.06 ± 0.03 ? with a 25% uncertainty at the given reference plasma parameters. The knowledge of the Stark broadening parameter of the 636.23 nm line may be important in the diagnostics of the laser plasma experiments especially in the absence of the Hα-line.

关键词： Stark broadening Parameter LIBS OES ZnO Zinc Lines

An Approximation for the Doppler broadening Function and Interference Term Using Fourier Series

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World Journal of Nuclear Science and Technology 2012年第4期2卷 144-149页

作者： Alessandro da C. Goncalves Daniel A. P. Palma Aquilino S. Martinez Brazilian Nuclear Energy Commission Rio de Janeiro Brazil Department Nuclear Engineering Federal University of Rio de Janeiro Rio de Janeiro Brazil

The calculation of the Doppler broadening function and of the interference term are important in the generation of nuclear data. In a recent paper, Goncalves and Martinez proposed an analytical approximation for the calculation of both functions based in sine and cosine Fourier transforms. This paper presents new approximations for these functions, and , using expansions in Fourier series, generating expressions that are simple, fast and precise. Numerical tests applied to the calculation of scattering average cross section provided satisfactory accu- racy.

关键词： Doppler broadening Function Fourier Series New Formulation for the Interference

Translational Motion of a Free Large Polaron and broadening of Absorption Spectra

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Journal of Modern Physics 2010年第1期1卷 9-16页

作者： Vladimir Mukhomorov 不详

The translational motion of a large polaron as whole is analyzed in the context of its effect on the broadening of an absorption optical spectrum. It was open question how important the role of translational degrees of freedom and the corresponding velocities are on the broadening. The Bogolyubov method of canonical transformation of coordinates is formulated for a system of an electron and field, taking into account rigorous fulfillment of the conservation laws. Separation of variables is carried out for the coordinates describing the translational degrees of freedom and the electron oscillations in a polarization well. The equations obtained for the electronic states explicitly depend on the velocity of the free polaron as a whole. An estimate is made for free polaron in ammonia.

关键词： Large Polaron Translational Motion Canonical Transformation broadening Absorption Spectra Ammonia