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A new water pusher were made, including the acrylic disc that had been installed in the previous expedition, the excessive press in the liner of the transducers broke it. The length of the water pusher now is the 122 cm same like the beginning and like is indicated in the label.
For hard rock samples the P-Wave was turned off
The service to the water pump
was8was carried out at the end of the expedition
X-Ray Imager
- X-Ray source was changed because present a low energy level indicated by pop up window warning wen the source ramp start to go up. That issue was detected in previous expedition when the recommended solution was change the source. calibration were made and actualized the image parameters because with the new source the energy is higher (note: do not use more than 100 kV or the high alarm could be triggered)
- 0.5cm offset is present in the ruler at side of processed images
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Some modifications requested by the scientists were made in the MAD spreadsheet to carry out repetitions of the measurements of the samples, these changes were reverted before the end of the expedition.
It is requested that a signal be added to the tare button to remind scientists to do this operation when weighing samples. if that operation is not carried out in 6 hours (configurable), the timer will require the tare before continuing.
- Cleaning service to the air pump was carried out at the end of expedition as is explained in the air pump maintenance manual.
Mad Test
During the expedition, the scientists asked what was the minimum size to measure in the MAD, when searching in the literature, reference is made to the fact that a larger volume is better since the gas has less space to fill, so it is a more precise measurement, but ... how small is too small?.
An experiment is designed in which a solid cylindrical rock sample is taken, which is measured according to the protocol of method C, saturating the rock for 4 hours, determining the wet weight, then drying in an oven for 24 hours, cooling and measuring the dry weight, to then measure in pycnometer volume density etc. pieces of the rock were progressively cut to reach a minimum size in which the standard error of the measured parameters is greater than 2%
Results
The initial volume of samples was around 10cc, that values of density was taken like true values. The initial volume of samples was around 10 cc, so density values ¿¿were taken as real values. the volumes after cutting were ~7.5cc, ~3.6cc, ~2.1cc, ~0.9cc, ~0.5cc whose values ¿¿of bulk density, dry density and grain density are shown in the following table.
| Bulk density (g/cm³) | Cell number | 10.2 | 7.5 | 3.6 | 2.1 | 0.9 | 0.5 |
| 1 | 2.893 | 2.898 | 2.87 | 2.919 | 2.854 | 2.869 | |
| 2 | 2.993 | 3.003 | 2.977 | 3 | 2.912 | 2.951 | |
| 3 | 2.939 | 2.943 | 2.945 | 2.965 | 3.023 | 2.969 | |
| 4 | 2.969 | 2.968 | 2.985 | 3.032 | 3.07 | 3.093 | |
| 5 | 2.917 | 2.926 | 2.971 | 3.015 | 3.354 | ||
| 6 | 2.906 | 2.925 | 2.947 | 2.961 | 2.715 | ||
| std desv | 0.035253 | 0.033810337 | 0.045406 | 0.036211 | 0.072684 | 0.198037384 | |
| average | 2.936167 | 2.943833333 | 2.94425 | 2.972333 | 2.9725 | 2.991833333 |
| Dry density (g/cm³) | Cell number | 10.2 | 7.5 | 3.6 | 2.1 | 0.9 | 0.5 |
| 1 | 2.867 | 2.872 | 2.844 | 2.893 | 2.83 | 2.843 | |
| 2 | 2.982 | 2.994 | 2.968 | 2.99 | 2.902 | 2.935 | |
| 3 | 2.928 | 2.935 | 2.934 | 2.951 | 3.012 | 2.955 | |
| 4 | 2.954 | 2.954 | 2.971 | 3.011 | 3.054 | 3.077 | |
| 5 | 2.9 | 2.909 | 2.956 | 2.995 | 3.326 | ||
| 6 | 2.89 | 2.909 | 2.935 | 2.946 | 2.691 | ||
| std desv | 0.0391 | 0.038589362 | 0.051319 | 0.037895 | 0.074332 | 0.197313977 | |
| average | 2.920167 | 2.928833333 | 2.92925 | 2.956 | 2.9565 | 2.971166667 |
| Grain density (g/cm³) | Cell number | 10.2 | 7.5 | 3.6 | 2.1 | 0.9 | 0.5 |
| 1 | 2.942 | 2.945 | 2.918 | 2.968 | 2.898 | 2.918 | |
| 2 | 3.015 | 3.02 | 2.994 | 3.021 | 2.932 | 2.981 | |
| 3 | 2.96 | 2.96 | 2.967 | 2.994 | 3.046 | 2.996 | |
| 4 | 2.997 | 2.996 | 3.012 | 3.073 | 3.103 | 3.127 | |
| 5 | 2.95 | 2.956 | 2.999 | 3.054 | 3.418 | ||
| 6 | 2.935 | 2.954 | 2.969 | 2.991 | 2.755 | ||
| std desv | 0.029409 | 0.026872642 | 0.035436 | 0.035814 | 0.071477 | 0.204793188 | |
| average | 2.9665 | 2.971833333 | 2.97275 | 3.004 | 3.004 | 3.0325 |
Conclusions
The standard error in each test was increasing while the piece was smaller, this is expected according to the reviewed literature, reaching over 10% in volumes close to 0.5cc, far from what was calculated with the 7.5cc in which the standard error it reaches only 0.65%. We usually use 2% as the maximum standard error in our measurements of physical properties, a value that is reached with 0.9cc in which the standard error reaches 3.5% as maximum, so I would recommend using 1cc as the minimum readable size in these cells since what values Minors exceed the 2% allowable error. (see table below)
Automated Vane Share (AVS)
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