High-end spectrophotometric analytical instruments are typically employed in academic institutions and industrial research laboratories and are rarely available for experimenters or younger students. An affordable high-tech robotic product manufactured by Lego may be employed as a single-beam monochromatic light source, detector and display to demonstrate and investigate the Beer-Lambert law us...

Lambert-Eaton myasthenic syndrome is a rare and acquired autoimmune disorder. We describe two female patients with medial rectus paresis as the only ocular manifestation. After a unilateral medial rectus recession and lateral rectus resection procedure, both patients recovered normal adduction. To our knowledge, this is the first report of surgery for extraocular muscle paresis in Lambert-Eaton...

Subsurface hydrothermal degradation of yttria stabilized tetragonal zirconia polycrystals (3Y-TZP) is presented. Evaluation of low temperature degradation (LTD) phase transformation induced by aging in 3Y-TZP is experimentally studied by Raman confocal microspectroscopy. A non-linear distribution of monoclinic volume fraction is determined in depth by using different pinhole sizes. A theoretica...

published a modification of Pearson’s method, in which a mixture of all the reagents was added at once. In our laboratory, we introduced a method which also requires only a single reagent. The density of the green color (Lieberman-Burchard reaction) is read in the Klett-Summerson photocolorimeter, using a 600-rn/A filter. In the normal range (140-280 mg./100 ml.), the values obtained with the n...

An original image analysis method is presented to characterize multi-walled carbon nanotubes from transmission electron microscopy images. The analysis is performed in three steps: (i) image preprocessing in order to isolate the nanotubes from the background, (ii) image segmentation, aiming at keeping only the measurable sections of nanotubes, and finally (iii) tube characteristics measurement....

A simple spectrophotometric method is developed for the determination of phosphate in sugar cane juice, water and detergent samples. The method is based on the formation of phosphomolybdate with added molybdate followed by its reduction with sodium sulphide in aqueous sulfuric acid medium. The system obeys Lambert-Beer’s law at 715 nm in the concentration range 0.3-12.24 ppm. Molar absorptivity...