FACE-DEPENDENT WORK FUNCTION DERIVED FROM THE LOCAL POLARIZATION OF PLASMA AND THE IMAGE FORCE ACTION NEAR A METAL SURFACE

1999 ◽  
Vol 13 (29n30) ◽  
pp. 1081-1085 ◽  
Author(s):  
K. F. WOJCIECHOWSKI ◽  
A. KIEJNA ◽  
H. BOGDANÓW
Keyword(s):  
Work Function ◽  
Metal Surface ◽  
Image Force ◽  
Force Action ◽  
Simple Method ◽  
Method Of Calculation ◽  
The Face ◽  
Local Polarization ◽  
Work Functions ◽  
Good Agreement

The concepts of the spontaneous polarization of plasma near the metal surface and of the image force are used to propose a simple method of calculation of the face-dependent work function. The calculated work functions for low index planes of aluminium and sodium are in good agreement with experiment.

scholarly journals Анизотропия поверхностной энергии и работы выхода электрона IIВ металлов

2019 ◽  
Vol 89 (2) ◽  
pp. 306
Author(s):  
И.Г. Шебзухова ◽  
Л.П. Арефьева
Keyword(s):  
Experimental Data ◽  
Surface Energy ◽  
Work Function ◽  
Statistical Method ◽  
Electron Work Function ◽  
Method Of Calculation ◽  
Cadmium Zinc ◽  
Good Agreement

AbstractOn the basis of electron-statistical method of calculation of the surface energy of metals, a technique for estimating the electron work function of hexagonal and rhombohedral metallic crystals has been developed. This technique relates surface energy to work function and can thus be applied to estimate the surface energy of crystal faces from experimental data for a work function. Computations have been made for cadmium, zinc, and mercury macrocrystals. The temperature and orientation dependences of both quantities have been constructed. Our results are in good agreement with literature experimental data.

A Streamline Curvature Method for Calculating S1 Stream Surface Flow

1984 ◽  
Vol 106 (2) ◽  
pp. 306-312
Author(s):  
S. K. Mao ◽  
D. T. Li
Keyword(s):  
Surface Flow ◽  
Approximation Technique ◽  
Flow Section ◽  
Boolean Expression ◽  
Simple Method ◽  
Stream Surface ◽  
Streamline Curvature ◽  
Calculation Results ◽  
Good Agreement ◽  
Streamline Curvature Method

A streamline curvature method for calculating S1 surface flow in turbines is presented. The authors propose a simple method in which a domain of calculation can be changed into an orderly rectangle without making coordinate transformations. Calculation results obtained on subsonic and transonic turbine cascades have been compared with those of experiment and another theory. Good agreement has been found. When calculating blade-to-blade flow velocity at subsonic speed, a function approximation technique can be used in lieu of iteration method in order to reduce calculation time. If the calculated flow section is of a mixed (subsonic-supersonic) flow type, a Boolean expression obtained from the truth table of flow states is proposed to judge the integrated character of the mixed flow section. Similarly, another Boolean expression is used to determine whether there exists a “choking” of the relevant section. Periodical conditions are satisfied by iterating the first-order derivative of stagnation streamline, which is formed simultaneously. It can be proved that the stagnation streamline formed in this way is unique.

Analysis of SINR for Unitary and Non-Unitary Precoded MIMO Systems

2011 ◽  
Vol 460-461 ◽  
pp. 414-419
Author(s):  
Xin Lu ◽  
Xiong Xu ◽  
Jian Hu Wang
Keyword(s):  
Computational Complexity ◽  
Mimo Systems ◽  
Original Method ◽  
Coding System ◽  
Simple Method ◽  
Method Of Calculation ◽  
Term Evolution ◽  
3Gpp Long Term Evolution ◽  
Output Sinr

Pre-coding type can be grouped into two approaches, unitary or non-unitary for 3GPP Long Term Evolution(LTE). Output SINR of unitary Pre-coding for MU-MIMO is investigated in this paper. A more simple method of calculation for SINR is presented, which Leads to the computational complexity down to 18% compared with original method, while calculating MIMO Pre-coding system with 4 matrices (i.e. 8 vectors). In addition, we also analyzed the loss of SINR when using unitary or non-unitary Pre-coding. Corresponding simulations show that output SINR of non-unitary pre-coding system is inferior to the unitary pre-coding case and such losses can been described using statistical linear approximation.

Calcul des éléments dipolaires et quadrupolaires de la matrice de transition moléculaire dans Na2

1990 ◽  
Vol 68 (4-5) ◽  
pp. 365-368 ◽  
Author(s):  
K. Hussein ◽  
O. Babaky
Keyword(s):  
Numerical Integration ◽  
Electronic States ◽  
Transition Elements ◽  
Simple Method ◽  
Selection Rules ◽  
Variable Formula ◽  
Method Of Calculation ◽  
Analytical Integration ◽  
Fifth Order

In this paper, we study a calculation of the transition elements [Formula: see text] between electronic states of the diatomic molecules Na2. We show the necessary selection rules for the determination of these operators by a method of analytical integration on the variable [Formula: see text], combined with a numerical integration to fifth order. The values found by this simple method of calculation are very reasonable and show that the important transitions [Formula: see text], [Formula: see text]; and [Formula: see text] of the dimer Na2 are dipolar. [Traduit par la revue]

Numerical Modelling of Circulation in Lake Sperillen, Norway

2000 ◽  
Vol 31 (1) ◽  
pp. 57-72 ◽  
Author(s):  
N. R. B. Olsen ◽  
D. K. Lysne
Keyword(s):  
Numerical Model ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Field Measurements ◽  
Navier Stokes ◽  
Water Current ◽  
Simple Method ◽  
Vertical Temperature Profile ◽  
Navier Stokes Equations ◽  
Good Agreement

A three-dimensional numerical model was used to model water circulation and spatial variation of temperature in Lake Sperillen in Norway. A winter situation was simulated, with thermal stratification and ice cover. The numerical model solved the Navier-Stokes equations on a 3D unstructured non-orthogonal grid with hexahedral cells. The SIMPLE method was used for the pressure coupling and the k-ε model was used to model turbulence, with a modification for density stratification due to the vertical temperature profile. The results were compared with field measurements of the temperature in the lake, indicating the location of the water current. Reasonably good agreement was found.

Influence of cathode material type on the electrical breakdown behaviors of DC discharge

2020 ◽  
Vol 98 (8) ◽  
pp. 726-731
Author(s):  
F. Diab ◽  
W.H. Gaber ◽  
M.E. Abdel-kader ◽  
B.A. Soliman ◽  
M.A. Abd Al-Halim
Keyword(s):  
Cathode Material ◽  
Work Function ◽  
Breakdown Voltage ◽  
Cathode Materials ◽  
Electrical Breakdown ◽  
Ionization Efficiency ◽  
Parallel Plates ◽  
Maximum Value ◽  
Dc Discharge ◽  
Work Functions

Paschen curves were studied using different cathode materials such as magnesium, zinc, and carbon graphite by discharge in argon gas of a pressure range between 0.08 and 3 Torr using a parallel plates configuration. The first and second Townsend coefficients (α and γ, respectively) and the ionization efficiency (η) of different cathode materials were deduced from Paschen curves as a function of the reduced field (E/P). The minimum breakdown voltage was found to be about 242 V for Mg material, which has the lowest work function, while carbon graphite has a higher breakdown voltage of 283 V due to its higher work function. The second coefficient γ was increased as a function of E/P and has higher values for materials of lower work functions, and a similar trend of γ is obtained as a function of the ion mean energy. On the other hand, the first coefficient α has a reverse behavior with both E/P and the work function of the cathode materials compared with the second coefficient. The ionization efficiency of the three cathode materials is identical, as η depends only on the gas properties and not the cathode material. η has a maximum value of about 0.025 V−1 for an E/P of about 185 Vcm−1Torr−1, corresponding to the maximum ionizing ability of electrons. The validation of the breakdown results has been confirmed by conferring with other published experimental measurements.

MXenes with tunable work functions and their application as electron- and hole-transport materials in non-fullerene organic solar cells

2019 ◽  
Vol 7 (18) ◽  
pp. 11160-11169 ◽  
Author(s):  
Zhimeng Yu ◽  
Wei Feng ◽  
Wanheng Lu ◽  
Bichen Li ◽  
Hongyan Yao ◽  
...  
Keyword(s):  
Solar Cells ◽  
Work Function ◽  
Organic Solar Cells ◽  
Hole Transport ◽  
Work Functions

The work function of 2D Ti3C2Tx can be tuned in a range from 4.08 to 4.95 eV.

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