scholarly journals Theory and Calculation of Nontraditional Stable Isotope Fractionation

2021 ◽  
Vol 2083 (2) ◽  
pp. 022111
Author(s):  
Zhenyu Han ◽  
Guilin Han
Keyword(s):  
Theoretical Calculation ◽  
Calculation Method ◽  
Harmonic Approximation ◽  
Volume Effect ◽  
Nuclear Volume ◽  
Anharmonic Effect ◽  
Stable Isotope Fractionation ◽  
Isotopic Studies ◽  
Dynamics Method ◽  
Equilibrium Fractionation

Abstract This paper conducts processing on isotope anharmonic effect with molecular dynamics method and Monte Carlo method based on path integration. It introduces the theoretical calculation method of pressure effect, and finally the nuclear volume effect and its theoretical calculation method, stressing that the nuclear volume effect is an important part of isotopic studies of heavy metals in the future. This paper makes an analysis on the equilibrium fractionation theory based on simple harmonic approximation.

scholarly journals Analysis of Seepage Characteristics of a Foundation Pit with Horizontal Waterproof Curtain in Highly Permeable Strata

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1303
Author(s):  
Chenghua Shi ◽  
Xiaohe Sun ◽  
Shengli Liu ◽  
Chengyong Cao ◽  
Linghui Liu ◽  
...  
Keyword(s):  
Hydraulic Conductivity ◽  
Theoretical Calculation ◽  
Calculation Method ◽  
Design Method ◽  
Water Pressure ◽  
Water Inflow ◽  
Deep Foundation ◽  
Foundation Pit ◽  
Deep Foundation Pit ◽  
Seepage Characteristics

At present, jet-grouted horizontal waterproof curtain reinforcement has become an essential method for deep foundation pit groundwater control. However, there is still a lack of an effective theoretical calculation method for horizontal waterproof curtain reinforcement, and there is little research on the seepage laws of foundation pits under different horizontal waterproof curtain conditions. Based on Darcy’s seepage theory, theoretical analysis models of deep foundation pit seepage were established considering the effect of a horizontal curtain in a highly permeable formation. Through the established models, the calculation method of the water inflow and the water pressure under the condition of a horizontal curtain was derived. Then through indoor tests, the reliability of the theoretical calculation method was verified. Furthermore, the established theoretical calculation method is used to analyze the influence of various factors on the water inflow and the water pressure, such as the ratio of hydraulic conductivity of the horizontal curtain to surrounding soil, thickness, and reinforcement position of the horizontal curtain. It is found that the hydraulic conductivity ratio has the most significant influence on the seepage characteristics of the foundation pit. Finally, the design method was applied to an example of the horizontal waterproof curtain of the foundation pit, which is located at Juyuanzhou Station in Fuzhou (China). The water inflow per unit area is 0.36 m3/d in the foundation pit, and this implies that the design method of the horizontal waterproof curtain applied for the excavation case is good and meets the requirements of design and safety.

Theoretical and Numerical Calculation on the Added Mass of Ahmed Body

2017 ◽  
Vol 865 ◽  
pp. 247-252
Author(s):  
Gui Tao Du
Keyword(s):  
Numerical Calculation ◽  
Theoretical Calculation ◽  
Calculation Method ◽  
Aerodynamic Drag ◽  
Added Mass ◽  
The Body ◽  
Power Performance ◽  
Car Body ◽  
The Impact ◽  
Ahmed Body

Because of the added mass, the aerodynamic drag of the automobile will increase obviously when accelerating in the still air. In this paper, it firstly gave the definition of the added mass, and presented that there was little research on the calculation of the added mass of automobile. Then through the analysis of the theoretical calculation method for the added mass, it pointed out that, for the added mass of the car-body with a complex shape, there was much difficulty in the theoretical calculation. Alternatively, a numerical calculation method for the added mass of car-body was derived. The simulation model adopted the Ahmed body and the corresponding verification experiment was completed in the Tongji Automotive Wind Tunnel center. The results indicate that the added mass is a constant which is only dependent on the body-shape. For the model investigated, the added mass is 0.0052kg that is approximately equal to the air displaced by the car-body. As the body accelerates to 4m/s2, the aerodynamic drag is increased by 1.89% because of added mass. Therefore, it needs to pay more attention to the impact that the added mass has on the dynamic performance of vehicle when proceeding the aerodynamic designs (especially for the high power performance vehicles). Meanwhile, it still makes a correction to the conventional aerodynamic drag formula. This paper also demonstrates that, with the analysis of the flow-field of car-body, the added mass essentially stems from the additionally work done by the car-body to increase the kinetic energy of external fluid as it speeds up.

scholarly journals Theoretical calculation method for crack resistance of jacketed RC columns

2019 ◽  
Vol 708 ◽  
pp. 012059 ◽  
Author(s):  
Pavlo Krainskyi ◽  
Pavlo Vegera ◽  
Roman Khmil ◽  
Zinoviy Blikharskyy
Keyword(s):  
Theoretical Calculation ◽  
Crack Resistance ◽  
Calculation Method ◽  
Rc Columns

Average value of the shape and direction factor in the equation of refractive index

2017 ◽  
Vol 31 (29) ◽  
pp. 1750263 ◽  
Author(s):  
Tao Zhang
Keyword(s):  
Refractive Index ◽  
Theoretical Calculation ◽  
Calculation Method ◽  
Electromagnetic Induction ◽  
Optical Materials ◽  
Electron Cloud ◽  
Refractive Indices ◽  
Average Value ◽  
Electron Clouds ◽  
Induction Energy

The theoretical calculation of the refractive indices is of great significance for the developments of new optical materials. The calculation method of refractive index, which was deduced from the electron-cloud-conductor model, contains the shape and direction factor [Formula: see text]. [Formula: see text] affects the electromagnetic-induction energy absorbed by the electron clouds, thereby influencing the refractive indices. It is not yet known how to calculate [Formula: see text] value of non-spherical electron clouds. In this paper, [Formula: see text] value is derived by imaginatively dividing the electron cloud into numerous little volume elements and then regrouping them. This paper proves that [Formula: see text] when molecules’ spatial orientations distribute randomly. The calculations of the refractive indices of several substances validate this equation. This result will help to promote the application of the calculation method of refractive index.

Analysis on Motion Precision Reliability of Hydraulic Support

2011 ◽  
Vol 48-49 ◽  
pp. 224-227
Author(s):  
Dong Chen Qin ◽  
Qiang Zhu ◽  
Hong Xia Wu ◽  
Zhe Feng Guo
Keyword(s):  
Mathematical Model ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Theoretical Calculation ◽  
Calculation Method ◽  
Effective Length ◽  
Future Research ◽  
Hydraulic Support ◽  
Continuous Contact ◽  
Continuous Contact Model

In order to research the motion precision reliability of hydraulic support when the influence of the bar length error and gap error is considered, the motion trace mathematical model for the top beam of hydraulic support is established, with the calculation method of motion precision reliability and the effective length of bar based on continuous contact model. Taking some type of hydraulic support as an example, its motion precision reliability is calculated and analyzed. The Monte Carlo simulation is also used to verify the model, and the T-R curve of the gap error and the reliability is plotted. The results from simulation accord with those from the theoretical calculation, which verifies the model established and can provide some valuable reference for the related future research.

scholarly journals A Study on Theoretical Calculation Method of Subway Safety Evacuation

2014 ◽  
Vol 71 ◽  
pp. 597-604 ◽  
Author(s):  
Bing Zhang ◽  
Zhi-sheng Xu ◽  
Qian-wei Zhao ◽  
Yang-yang Liu
Keyword(s):  
Theoretical Calculation ◽  
Calculation Method ◽  
Safety Evacuation

Experimental Research of Cable in Plate Method

2013 ◽  
Vol 351-352 ◽  
pp. 919-922
Author(s):  
Ping Pang ◽  
Xin Sheng Yin
Keyword(s):  
Theoretical Calculation ◽  
Experimental Research ◽  
Prestressed Concrete ◽  
Calculation Method ◽  
Concrete Slab ◽  
Plate Method

According to the research, a new arrangement method of prestressed concrete slab is provided. It has not been mentioned before and this article discussed unbonded prestressed concrete slab system, and gives the theoretical calculation method.

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