Particle-size analyses of Widgelli Parna in South-east Australia

Soil Research ◽  
1981 ◽  
Vol 19 (3) ◽  
pp. 355 ◽  
Author(s):  
G Blackburn
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Clay Fraction ◽  
Important Distinction ◽  
Frequency Distributions ◽  
Aeolian Sediments ◽  
Average Grain Size ◽  
Two Samples ◽  
Mean Diameter

Difficulties in using granulometry to characterize the non-clay fraction of the presumed aeolian sediments known as parna are considered by reference to the results of repeated analyses of samples. Incomplete dispersion of clap accounted for different results with two samples, one being from material identified as subplastic. Bimodal size frequency distributions were detected for several samples, a condition which should invalidate modal diameter as the measure of average grain size. Mean diameter is regarded as an appropriate measure for the samples. The more accurate results obtained for the samples do not upset the earlier conclusions regarding distribution of Widgelli parna, but they suggest an important distinction between the western and eastern samples of the material. Suggestions are made concerning determination of particle size for parna samples.

Effect of Warm Rolling on Microstructure and High Temperature Mechanical Behavior of a Nano-Structured Al-8Fe-2Mo-2V-1Zr Alloy

2005 ◽  
Vol 486-487 ◽  
pp. 411-414 ◽  
Author(s):  
Won Yong Kim ◽  
Jae Sung Park ◽  
Mok Soon Kim
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Elevated Temperatures ◽  
Hot Extrusion ◽  
Warm Rolling ◽  
Spray Forming ◽  
Grain Structure ◽  
Average Grain Size ◽  
Two Samples ◽  
Additional Process

Mechanical properties of a nano-structured Al-8Fe-2Mo-2V-1Zr alloy produced by spray forming and subsequent hot-extrusion at 420°C were investigated in terms of tensile test as a function of temperature. Warm rolling was adapted as an additional process to expect further refinement in microstructure. Well-defined equiaxed grain structure and finely distributed dispersoids with nano-scale in particle size were observed in the spray formed and hot extruded sample (as-received sample). The average grain size and particle size were measured to 500 nm and 50 nm, respectively. While it was found that warm rolling gives rise to precipitate fine dispersoids less than 10 nm without influencing the grain size of matrix phase, in the temperature range of RT∼150°C, distinguishable changes in ultimate tensile strength were not found between the as-received and warm-rolled samples. At elevated temperatures ranging from 350 to 550°C, warm-rolled sample showed a higher value of elongation than as-received one although similar values of elongation were observed between two samples at temperatures lower than 350°C.

scholarly journals MINERAL COMPOSITION OF SOME LATGALE LAKE SEDIMENTS

2019 ◽  
Vol 1 ◽  
pp. 304
Author(s):  
Rasma Tretjakova ◽  
Andris Karpovičs
Keyword(s):  
Grain Size ◽  
Lake Sediments ◽  
Size Distribution ◽  
Clay Minerals ◽  
Mineral Composition ◽  
Grain Size Distribution ◽  
Sandy Loam ◽  
Clay Fraction ◽  
Fine Grained ◽  
Two Samples

Our research is focused on sedimentological conditions and postdepositional changes of recent fine grained lake sediments. We used bulk sediment mineralogical composition and grain size distribution as indicators to identify sediment source areas and possible changes during Holocene. We analysed fine grained (clayey) sediments from three Latgale lakes - Zeili, Pauguļi and Plusons, situated in Latgale upland. Lake sediments cover Late Pleistocene glacial deposits – loam and sandy loam. Bulk mineral composition of 6 sediment samples was determined by X-ray diffraction (XRD). Sediments contained typical minerals found in surrounding glacial sediments: rock-forming minerals as quartz, plagioclase, albite, enstatite, dolomite, calcite, and clay minerals - illite, kaolinite. To identify postdepositional changes in lake sediments of Holocene age clay minerals in clay fraction (<2 mkm) should be analysed. Particularly illite, smectite mixed layered minerals - illite/smectite (I/Sm) and chlorite. Additionally, grain size distribution of studied lake sediments was analysed. Accordingly, our studied sediments are clays, silty clays and clayey silts with bimodal particle distribution, except two samples from Zeiļi and Plusons with unimodal distribution.

Study on the Microstructure and Properties of ZL205A Alloy under Partial Remelting Treatment

2012 ◽  
Vol 538-541 ◽  
pp. 1183-1186
Author(s):  
Min Li ◽  
Lan Rong Cai ◽  
Peng Xin Liu
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Tensile Strength ◽  
Average Particle Size ◽  
Average Particle ◽  
High Tensile Strength ◽  
Microstructure And Properties ◽  
Partial Remelting ◽  
Average Grain Size ◽  
Zl205a Alloy

In this paper, effects of partial remelting treatment on microstructure and properties of ZL205A alloy were studied in detail. The results show that the grain size of ZL205A alloy decreases at different degree. The grain size increases first and then decreases with increasing of returns content. The average grain size of the primary ZL205A alloy was measured to be about 60 μm, and the good result can be got of the ZL205A alloys with the average particle size of α (Al) phase being about 33 μm after adding 20wt.% returns. The ZL205A alloy with 20 wt.% returns has a considerably high tensile strength and yield strength of 525MPa and 445 MPa, respectively, which is much higher than 501 MPa and 421 MPa of primary ZL205A alloy, meanwhile the elongation level is up to14%.

scholarly journals Contribution of Particles Size Ranges to Sand Friction

2013 ◽  
Vol 3 (4) ◽  
pp. 497-501 ◽  
Author(s):  
E. Mostefa Kara ◽  
M. Meghachou ◽  
N. Aboubekr
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Granular Material ◽  
Physical Properties ◽  
Friction Angle ◽  
Direct Shear ◽  
Shear Tests ◽  
Direct Shear Tests ◽  
Marine Sand

This work studies the correlation between certain physical properties of granular material such as the friction angle and the grain size distribution. In the laboratory, the determination of friction angle requires hard and expensive testing. Prediction of this parameter from the grading curve proves to be very interesting. Direct shear tests were performed on actual marine sand of Tergha (Algeria) and on seventeen different samples arranged from the same sand with various particle size ranges. Results showed that the friction angle of sand is a result of contribution of various constituent granular classes.

scholarly journals Colour characteristics of winter wheat grits of different grain size

2015 ◽  
Vol 8 (1) ◽  
pp. 70-77 ◽  
Author(s):  
Zs. H. Horváth ◽  
A. Véha
Keyword(s):  
Grain Size ◽  
Hardness Index ◽  
Whiteness Index ◽  
Average Grain Size ◽  
Colour System ◽  
L Value ◽  
Different Grain Size ◽  
Baking Industry ◽  
The Relationship

Abstract Nowadays, wheat has spread all over the world due to its extensive usability. The colour of wheat grits is very important for the milling and baking industry because it determines the colour of the products made from it. The instrumental colour measuring is used, first of all, for durum wheat. We investigated the relationship between colour characteristics and grain size in the case of different hard aestivum wheats. We determined the colour using the CIE (Commission Internationale de l’Eclairage) 1976 L*, a*, b* colour system measured by MINOLTA CR-300 tristimulus colorimeter. After screening the colour of the wheat fractions of different grain size, grits was measured wet and dry. We determined the L*, a*, b* colour co-ordinates and the whiteness index, too. To evaluate the values we had obtained, we used analysis of variance and regression analysis. We pointed out that the colour of wheat grits of different grain size is dependent on the hardness index of wheat. The lightness co-ordinate (L*) of grits of the harder wheat is smaller, while a* and b* co-ordinates are higher. We also found that while grain size rises, the L* co-ordinate decreases and a*, b* values increase in the case of every type of wheat. The colour of grits is determined by the colour of fractions of 250-400 μm in size, independently from the average grain size. The whiteness index and the L* colour co-ordinate have a linear relation (R2 = 0.9151); so, the determination of whiteness index is not necessary. The L* value right characterizes the whiteness of grits.

scholarly journals DESIGN OF EXPERIMENTS AIMED AT THE DETERMINATION OF THE THERMAL CONDUCTIVITY OF SANDY SOIL BASED ON GRAIN-SIZE COMPOSTION

2019 ◽  
Vol 6 (4) ◽  
pp. 36-38
Author(s):  
Александр Захаров ◽  
Aleksandr Zaharov ◽  
Станислав Маховер ◽  
Stanislav Mahover
Keyword(s):  
Thermal Conductivity ◽  
Particle Size ◽  
Grain Size ◽  
Particle Size Distribution ◽  
Sandy Soil ◽  
Size Composition ◽  
Laboratory Research ◽  
Experiment Planning ◽  
Research Model

The article is focused on laboratory research in order to obtain the thermal conductivity of the soil, depending on the grain-size composition. The technological sequence of the experiment has been developed. The sequence of planning the experimental research and the order of analysis of the data obtained are presented. The research model has been defined in the form of a regression equation, an experiment planning matrix has been compiled. During the tests, it is planned to obtain the dependence of the thermal conductivity of sandy soil on the change in its particle size distribution of 0.5; 0.25; 0,1, and also the dependence of various density and humidity of the studied sample.

Surface Preparation of Solid Metallic Samples for X-Ray Spectrochemical Analysis

1961 ◽  
Vol 5 ◽  
pp. 405-411
Author(s):  
R.E. Michaelis ◽  
Betty Ann Kilday
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Aluminum Alloy ◽  
Cast Iron ◽  
White Cast Iron ◽  
Surface Preparation ◽  
Critical Factor ◽  
Spectrochemical Analysis ◽  
X Ray

AbstractIn X-ray spectrochemical determinations, the surface preparation of metal samples is important since the emitted secondary radiation is absorbed except for that emerging from the immediate surface. Surface preparation also has been found to be a critical factor in eliminating or at least in minimizing the effects of certain metallurgical changes among or within samples on the X-ray determinations. For example, a change of particle size of an undissolved constituent, or a change in grain size, may markedly influence the X-ray analysis, depending on the surface preparation. A metallographic polishing technique, whereby the sample surfaces were finished with ¼μ diamond dust, was reported for the determination of lead in leaded steel (Kilday and Michaelis, in press). This investigation has been extended to other materials such as hypereutectic silicon-aluminum alloy and white-cast iron. A comparison is made of the effects of different surface preparations on X-ray determinations.

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