These include identifying suitable areas of vitreous ice at low magnification, determining the presence and location of specimen on the grid, automatically adjusting imaging parameters (focus, astigmatism) under low-dose conditions, and acquiring images at high magnification to either film or a digital camera.
To increase specimen flatness on the grid, a second carbon layer can be deposited to the side where the sample is exposed to air [ 69, 70].
The experimental test was reproduced numerically by finite element analysis and the recording of deformed grey level images by a CCD camera was simulated trying to take into account the most significant parameters that can play a role during an actual test, e.g. the noise, the failure of the specimen, the size of the grid printed on the surface, etc.
The specimen grid is carried in a small holder in a movable specimen stage.
Continuous carbon-film grids were glow-discharged (PELCO easiGlow, Redding, CA) at 15 mA for 30 s. Next, 5 µl specimen solution was loaded immediately onto the grid and blotted after 15 s.
The gold (Au) and silica (Si) peaks in the spectra in Fig. 5 originated from gold sputtering of the specimen and the silica grid used for support of the specimen respectively.
Experimental results indicated that the combined core sandwich specimens provided increased stiffness, specific stiffness, energy absorption and critical load, which were higher than the sum of honeycomb core sandwich specimens and grid core sandwich specimens.
Subsequently, the grid was blotted and plunged into liquid ethane to vitrify the specimen.
The speed with which the meniscus receded from the grid surface provided a useful indicator of the likely quality of the specimen.
A carbon-coated 200-mesh copper specimen grid was glow-discharged for 1.5 min. One drop of nanoparticle suspension was deposited on the grid and allowed to stand for 1.5 min after which any excess fluid was removed with filter paper.
Firstly, the generation methods of the random polyhedron aggregate and ITZ are introduced, as well as the process how to create the meso-scale finite element (FE) model of the concrete specimen through grid mapping method.
