Effect of grain size on radon emanation coefficient, surface and mass exhalation rates and the correlation coefficient between them in different masses of soil and phosphate fertilizer

2019 ◽  
Vol 107 (2) ◽  
pp. 129-139 ◽  
Author(s):  
Fatimh Alshahri
Keyword(s):  
Grain Size ◽  
Correlation Coefficient ◽  
Surrounding Medium ◽  
Phosphate Fertilizer ◽  
Radon Emanation ◽  
Exhalation Rate ◽  
Sample Mass ◽  
Emanation Coefficient ◽  
Grain Sizes ◽  
The Relationship

Abstract It is important to study the behavior of recoiling radon atoms 222Rn after decay of parent 226Ra and the effect of parameters on their access to the surrounding medium. The present study was carried out using CR-39 detector to study the effect of grain size on the correlation between surface and mass exhalation rates and the correlation between emanation coefficient and exhalation rate at different masses of soil and phosphate fertilizer. In addition, the relationship between emanation coefficient and the sample mass was studied for different grain sizes (0.1, 0.3, 0.5 and 1 mm). The results showed that there is no effect of grain sizes on the correlation coefficient between surface and mass exhalation rates in soil and fertilizer. The correlation coefficient between emanation coefficient and exhalation rate in different masses of soil was slightly influenced by the grain sizes. While the correlation coefficient between emanation coefficient and exhalation rate in different masses of phosphate fertilizer samples was not affected by the grain sizes (0.1, 0.3 and 0.5 mm). However, it was found that the emanation coefficient decreases exponentially with the mass for soil and phosphate fertilizer. This relationship was not significantly affected by grain size in soil except grain size 1 mm. While this relationship was affected by grain size >0.3 mm in phosphate fertilizer.

Microstructure Prediction by Finite Element Analysis during Hot Rolling of Magnesium Alloy Sheets

2015 ◽  
Vol 661 ◽  
pp. 105-112
Author(s):  
Yeong Maw Hwang ◽  
Tso Lun Yeh
Keyword(s):  
Grain Size ◽  
Magnesium Alloy ◽  
Optimal Conditions ◽  
Compression Tests ◽  
Element Analysis ◽  
Grain Sizes ◽  
Average Grain Size ◽  
Microstructure Prediction ◽  
Alloy Microstructure ◽  
The Relationship

Material’s plastic deformation by hot forming processes can be used to make the materials generate dynamic recrystallization (DRX) and fine grains and accordingly products with more excellent mechanical properties, such as higher strength and larger elongation can be obtained. In this study, compression tests and water quenching are conducted to obtain the flow stress of the materials and the grain size after DRX. Through the regression analysis, prediction equations for the magnesium alloy microstructure were established. Simulations with different rolling parameters are conducted to find out the relationship between the DRX fractions or grain sizes of the rolled products and the rolling parameters. The simulation results show that rolling temperature of 400°C and thickness reduction of 50% are the optimal conditions. An average grain size of 0.204μm-0.206μm in the microstructure is obtained and the strength and formability of ZK60 magnesium alloys can be improved.

Effects of Sputtering Conditions on Texture, Microstructure and Magnetic Properties of the CoCrPt/NiAl Thin Films

1998 ◽  
Vol 517 ◽  
Author(s):  
Y.-N. Hsu ◽  
D. E. Laughlin ◽  
D. N. Lambeth
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Magnetic Properties ◽  
Optimum Pressure ◽  
Grain Sizes ◽  
Maximum Value ◽  
Sputtering Power ◽  
Sputtering Pressure ◽  
The Relationship ◽  
Microstructure And Magnetic Properties

AbstractThe effects of sputtering argon pressures and sputtering power on the microstructure, texture and magnetic properties of NiAI underlayers on CoCrPt films were investigated. In this paper, the relationship between the sputtering conditions, microstructure, crystallographic texture and magnetic properties of these thin films will be discussed. By controlling the sputtering pressure and sputtering power, the texture and microstructure of NiAI underlayers were found to vary. This in turn was found to influence the magnetic properties of CoCrPt thin films. It was found that 10 mtorr is the optimum pressure to deposit the NiAl thin films to obtain the best magnetic properties for our system. At this argon pressure, the coercivity reached a maximum value because of the strongest CoCrPt (1010) texture and smallest grain size. At lower argon pressures (< 10 mtorr), NiAI tended to have a (110) texture reducing the CoCrPt (1010) texture, which in turn reduced the CoCrPt coercivity and S*. Also, high NiAl deposition pressures (>30 mtorr) yielded larger grains and a weaker CoCrPt (1010) texture, thereby decreasing the coercivity of the CoCrPt films. Increasing the sputtering power has been found to increase the CoCrPt coercivity and S* value. However, the grain sizes of the CoCrPt/NiAl thin films deposited at higher sputtering power were larger than those obtained at lower sputtering power.

Magnetron Co-Sputtering of Nanostructured Chromium Aluminium Nitride Coatings

2005 ◽  
Vol 475-479 ◽  
pp. 4001-4004
Author(s):  
Richard Wuhrer ◽  
Wing Yiu Yeung
Keyword(s):  
Grain Size ◽  
Cluster Formation ◽  
Nanostructured Coatings ◽  
Aluminium Nitride ◽  
Grain Sizes ◽  
Partial Pressures ◽  
Nitride Coatings ◽  
Controlled Deposition ◽  
The Relationship ◽  
Low Nitrogen

Ternary chromium aluminium nitride (Cr,Al)N coatings were produced by reactive magnetron co-sputtering technique at different nitrogen deposition pressures. Densified nanostructured coatings with grain size below 100 nm were obtained under critically controlled deposition conditions at low nitrogen partial pressures. The nanostructured coatings were generally of improved surface roughness and properties. Microhardness measurements showed that the coatings had much higher hardness than those of coarser grain sizes. It is believed that the refinement of the coating structure at low nitrogen pressures is associated with a larger number of atoms/molecules depositing on the substrate with higher energies, thus enhancing the adatom mobility and nucleated cluster formation in the coatings. The relationship between the grain size reduction and the deposition rate of the coatings was analysed.

scholarly journals Radon emission fluctuation as a result of biochar application into the soil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kamil Szewczak ◽  
Sławomir Jednoróg ◽  
Katarzyna Wołoszczuk ◽  
Łukasz Gluba ◽  
Anna Rafalska-Przysucha ◽  
...  
Keyword(s):  
Field Measurements ◽  
Radon Emanation ◽  
Radon Exhalation Rate ◽  
Laboratory Measurements ◽  
Exhalation Rate ◽  
Radon Exhalation ◽  
Emanation Coefficient ◽  
A Value ◽  
Simultaneous Decrease ◽  
The Impact

AbstractThe presented research was focused on the analysis of the impact of biochar application into the soil on the radon exhalation process as a new issue of radiation protection in agriculture. Field measurements of the radon exhalation rate utilizing two methods—active and passive as well as laboratory measurements of the radon emanation coefficient were performed. In laboratory a soil samples with sunflower husk biochar were analysed using the accumulation chamber technique. At the final step the assessment of the effective dose for humans coming from radon exhalation from soil depending on biochar dose applied were evaluated. The doses of biochar applied in the analysed experimental fields were 0, 20, 40, 60, 80, and 100 Mg ha−1. The results show that biochar application into the soil contribute to a decrease in the emanation coefficient from a value around 7% to less than 2% with a simultaneous decrease in the radon exhalation rate from 4.4 to 14.8 mBq m−2 s−1 when the biochar dose increase from 0 to 100 Mg ha−1.

Preparation of Barium Titanate Grain-Oriented Ceramics and their Piezoelectric Properties

2010 ◽  
Vol 445 ◽  
pp. 3-6 ◽  
Author(s):  
Rintaro Mori ◽  
Petr Pulpan ◽  
Hiroshi Hayashi ◽  
Yoshitaka Nagamori ◽  
Yuichi Yamamoto ◽  
...  
Keyword(s):  
Grain Size ◽  
Barium Titanate ◽  
Relative Density ◽  
Grain Growth ◽  
Piezoelectric Properties ◽  
Templated Grain Growth ◽  
Grain Sizes ◽  
Degree Of Orientation ◽  
High Degree ◽  
The Relationship

Barium titanate (BaTiO3, BT) grain-oriented ceramics along [110] direction were prepared by a templated grain growth (TGG) method. The [110] oriented BT platelike particles (t-BT) were used as template particles. BT grain-oriented ceramics with higher relative density (Drel) over 95 %, high degree of orientation along [110] direction (F110) over 80 % and grain sizes around 30 µm were successfully prepared using only the template particles. The relationship between microstructures and piezoelectric constant (d33) was investigated. The higher F110 was, the higher Drel and the smaller grain size were required for enhancement of the piezoelectric properties.

Relationship between Strength and Grain Size of Friction Stir Processed and Annealed High Purity Aluminum

2014 ◽  
Vol 922 ◽  
pp. 372-375
Author(s):  
Sho Kobayashi ◽  
Tomo Kawakatsu ◽  
Yorinobu Takigawa ◽  
Tokuteru Uesugi ◽  
Kenji Higashi
Keyword(s):  
Grain Size ◽  
Chemical Composition ◽  
Yield Stress ◽  
Coarse Grain ◽  
Petch Relation ◽  
Friction Stir ◽  
Grain Sizes ◽  
Fine Grain ◽  
High Purity Aluminum ◽  
The Relationship

A relationship between yield stress and grain size was examined in FSP-ed and annealed 5N-Al (99.9996% purity) in order to reveal the relationship on materials with equal chemical composition, because the large positive deviations of yield stress from the Hall–Petch relation obtained by plots with coarse grain size were reported in the fine grain sizes with SPD processed and we focused on amount of impurities during SPD processing about this phenomenon. The purity of FSP-ed samples on this study were 99.9988% Al (Fe +8at.ppm). Annealing this sample at various temperatures, the relationship between yield stress and grain sizes was obtained on materials with equal chemical composition. However, the yield stress of sample as FSP-ed is higher than that following Hall-Petch relation obtained by subsequently annealed samples plots. As a result, the positive deviation is occurred by factors other than the impurities.

Effects of Austenitizing Temperature and Cooling Rate on the Mechanical Properties of 36MnVS4 Steel for Automobile Engine Connecting Rod

2017 ◽  
Vol 898 ◽  
pp. 1195-1201 ◽  
Author(s):  
Jun Ru Li ◽  
Xiao Hang Sun ◽  
Yan Ji ◽  
Lie Chen ◽  
Guang Lei Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Cooling Rate ◽  
Connecting Rod ◽  
Austenitizing Temperature ◽  
Grain Sizes ◽  
Austenite Grain ◽  
Fracture Splitting ◽  
The Relationship ◽  
Prior Austenite Grain

The relationship between microstructure and mechanical properties of 36MnVS4 steel was studied. Different prior austenite grain sizes were obtained by austenitizing at 850, 950 and 1050 °C, respectively, and different ferrite contents were obtained by different cooling rates. Austenitizing temperature mainly influenced the grain size. With the austenitizing temperature increasing, grain size increased and the phase transformation starting temperature increased. Also, the strength increased and the plasticity and toughness decreased. Cooling rate mainly influenced the microstructure percentage. With the cooling rate increasing, ferrite percentage decreased and pearlite percentage increased. And meanwhile, the strength increased and ductility and toughness decreased. Microstructure had a significant influence on fracture splitting properties. With the grain size increasing, fracture splitting properties were markedly improved. With the ferrite percentage increasing and pearlite percentage decreasing, fracture splitting properties were worsened.

Grain Size Relationships between the Magnetic Layer and the Underlayers in CoCrPtTa Recording Media

2000 ◽  
Vol 614 ◽  
Author(s):  
Kai Ma ◽  
Robert Sinclair ◽  
Gerardo Bertero ◽  
Wei Cao
Keyword(s):  
Grain Size ◽  
Magnetic Layer ◽  
Recording Media ◽  
Processing Conditions ◽  
Magnetic Recording Media ◽  
Electron Microscopic ◽  
Grain Sizes ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
The Relationship

ABSTRACTThis article presents a transmission electron microscopic (TEM) investigation of the relationship between the magnetic and underlayer grain sizes in CoCrPtTa/CrMo longitudinal magnetic recording media. A great deal of effort has been expended on decreasing the underlayer grain size in order to decrease that of the magnetic layer. However, our results show that the two grain sizes may not always correlate. When the underlayer (CrMo) grains are sufficiently small, the magnetic layer (CoCrPtTa) grain size does not necessarily decrease with further underlayer grain size reduction. By carefully controlling the processing conditions, CrMo grain sizes were made to vary from 16nm down to 10nm. However, the corresponding CoCrPtTa grain sizes remained nearly the same. As the underlayer grain size decreased, the ratio of magnetic to underlayer grain size increased from 0.9 to 1.4.

Thermal Conductivity and Electrical Resistivity in Polycrystalline and Nanocrystalline Nickel

2011 ◽  
Vol 409 ◽  
pp. 561-565 ◽  
Author(s):  
S. Wang ◽  
I. Brooks ◽  
J.L. McCrea ◽  
G. Palumbo ◽  
G. Cingara ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Grain Size ◽  
Electrical Resistivity ◽  
Flash Method ◽  
Pulsed Current ◽  
Polycrystalline Nickel ◽  
Nanocrystalline Nickel ◽  
Annealed Condition ◽  
Grain Sizes ◽  
The Relationship

The grain-size dependences of thermal conductivity and electrical resistivity of polycrystalline and nanocrystalline nickel were measured by the flash method and four-point probe method, respectively. Nanocrystalline nickel (grain size: 28 nm) was made by the pulsed-current electrodeposition process, while polycrystalline nickel (grain size: 57 μm) was the same material in fully annealed condition. Noticeable differences in thermal conductivity and electrical resistivity were observed for both materials. These results can be explained on the basis of the rapid increase in the intercrystalline grain boundary and triple junction volume fractions at very small grain sizes. The relationship between thermal conductivity and electrical resistivity of nanocrystalline nickel follows the classic Wiedemann-Franz law.

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