Diamond knife

In earlier research the alignment operation was applied to CNTs in the form of a CNT-polymer resin [24] or CNT suspended in a solvent [25]. In the method developed by Ajayan et al. [24], purified MWCNTs were dispersed in an epoxy resin which was cut with a diamond knife and a microtome in order to obtain aligned CNTs. De Heer et al. [25] used a 0.2 (im pore ceramic filter in order to create an MWCNT suspension in ethanol, and to obtain a black deposit which was transferred to a plastic surface (Delrin or Teflon) by pressing the filter onto the polymer. However, only a moderate degree of orientation and uniformity in length of the CNTs was achieved by this method. 

Thin sections cut with a diamond knife microtome can be of great advantage in locating regions of catalyst where important chemical or structural changes take place during reaction. Comparison of equivalent areas of fresh and deactivated catalyst can be a difficult problem if the catalyst support does not have a uniform microstructure as in carbon supports produced from plant materials. Even when specimen selection and preparation are adequate, it may be difficult to know upon which image features to place the electron beam to solve the problem at hand. 

The goal of our investigations was to characterise the morphology of the sample, and to determine the size and location of the PTFE and silicone oil phases by different methods [46,47], For phase characterization using Raman microscopy, no special sample preparation was necessary. For FTIR imaging, microtomed sections (5 pm in thickness) had to be prepared by cutting the sample with a diamond knife at — 80°C ("cryo-microtomy") to prevent smearing and to obtain flat surfaces. 

III. Transmission electron microscopy of radish seeds Transmission electron microscopy (TEM) of radish seeds was done as listed below For TEM preparations, the specimens after fixation and dehydration, were embedded in Epon 812 resin (Luft, 1961). Thick sections (ca. 1mm each) were stained with 0.1% toluidine blue and observed with a Zeiss light photomicroscope. Thin sections, obtained with a diamond knife on a Supernova microtome, were sequentially stained at room temperature with 2% uranyle acetate (aqueous) for 5 min and by lead citrate for 10 min (Reynolds, 1963). Ultrastructural studies were made using a Philips CM12 transmission electrone microscope (TEM) operated at 80 KV. 

Section with glass knives or diamond knife and ultramicrotome. Note Usually thick sections (1 pm) are cut, affixed to glass microscope slides, and stained 5-15 min at 40-50°C with toluidine blue solution (1 g toluidine blue and 1 g of sodium borate in 100 mL H20), The block is then refaced so that the trapezoid encompasses the desired tissue. Thin sections of gray, silver, or gold interference colors are cut. 

Figure 2 shows STEM images of a 8%wt Pd/2%wt Pt catalyst which is supported on charcoal. The sample was prepared for microscopy by embedding in epoxy resin and sectioning with a diamond knife in an ultramicrotome, and was examined in a Vacuum Generator s Ltd HB5 STEM, with a 5A probe. The sample thickness is about 500A. 

Specimens were post-fixed in 1% OSO4 in sodium cacodylate buffer, dehydrated in ascending alcohol solutions, and embedded in Epon LX 112. Semi-thin sections (1.0 pm thickness) were cut with a diamond knife and stained with Richardson s dye (contains methylene blue) or PAS-reagent. Micrographs were made with an Olympus New Vanox microscope. 

Cut the resulting blocks with a diamond knife, and mount sections on nickel grids see Note 10). 

Cut the resulting blocks with a diamond knife, and mount sections on nickel grids. It is often advisable to cut the sections slightly thicker than normal such that the interference color of the sections is light gold (see Note 14). 

Cut gold sections with a diamond knife, and mount on nickel grids. To increase the adherence of the sections to the grids, after sectioning, the grids may be placed in a 60°C oven for 1 h. 

Fig. 1.—Nucleus (N) from D-Galactose-treated Orchid Seedling (Phalaenopsis cv. Doris Fi) Showing Dispersed Chromatin with Nuclear Envelope Envaginated (Arrows) into the Cytoplasm. [After treatment with D-galactose, seedlings were fixed in 2% glu-taraldehyde for 2 h followed by 2% OsO, for 12 h. Tissue was dehydrated in a graded concentration, embedded in Epon 812, sectioned with a diamond knife, and photographed with a Zeiss EM9A electron microscope x 13,340 (reproduced, by permission, from Ref. 533).]...

The electron micrographs of the various ERL-4221-CTBN systems were prepared with the osmium tetroxide technique (3). The castings were stained by reaction with osmium tetroxide vapors for 24 hours. Ultrathin specimens, approximately 1000 A thick, were cut with the Reichert OMU2, ultramicrotome equipped with a diamond knife and were stained again for one hour. The osmium tetroxide selectivity stained the rubber phase, while the epoxy remained unaffected, revealing many structural features in the polyphase systems with excellent contrast and... 

Small pieces of tissue are fixed for 1 hr in a mixture of 4% formaldehyde and 0.5% glutaraldehyde in 100 mM phosphate buffer (pH 7.4) (Chicoine and Webster, 1998). They are infiltrated with 2.3 M sucrose for 24 hr at 4°C, mounted with specimen pins (Leica, Deerfield, IL), and frozen by immersion in liquid nitrogen. The frozen tissue is sectioned at -110°C using an Ultracut E ultramicrotome (Leica) equipped with a diamond knife and an FC4 cryoattachment. Cryosections -60-80 nm thick are thawed and then mounted on Formvar-carbon-coated grids. 

The brominated sticks are embedded in Spurr epoxy resin (Spurr 1969) and sectioned with a diamond knife or glass knife mounted on an ultramicrotome to give cross sections of 0.15//m thickness for TEM-EDXA or 0.5//m thickness for SEM-EDXA. The sections are then placed on a carbon-coated collodion film on the specimen support grid. The specimens are carbon-coated again to avoid charging. 

For TEM observation, more complicated and careful sample preparation procedures are involved. Extreme care must be taken during sample preparation to avoid crosscontamination. The sample sometimes needs to be embedded in a medium such as epoxy resin that cures at 50X overnight before cutting by a microtome equipped with a diamond knife or thinning by electropolishing or ion beam. 

Ultra-thin sections (gold-silver) are cut using a diamond knife (Dupont Company) and ultramicrotome (Reichert Ultracut E, Austria), and the sections are contrasted with uranyl acetate and lead citrate (26) and examined with a JEOL (JEMlOlO) transmission electron microscope. 

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