Transmission electron microscopy solution preparation

In order to obtain Pt nanoparticles, aqueous solution of 10 M K2PtCl4, which contained 10 M (as monomer unit) of poly-NIPA or poly-NEA, was bubbled with Ar gas and then H2 gas. Then the reaction vessel was sealed tightly and kept in a water bath at a suitable temperature. At given reaction times, the vessels were opened and the samples for transmission electron microscopy (TEM) were prepared by soaking a grid (carbon substrate, Oken) in the colloidal solution and then drying it in the air. The TEM (Hitachi H-8100) was operated at 200 kV. 

Fig. 26. High -resolution transmission electron microscopy (HRTEM) image of perfluoropoly-ether-modified G3 PPI dendrimers containing Pd metal nanoclusters prepared on aholey carbon copper grid by evaporation of a dilute solution of the dendrimer composite. Reprinted with permission from Ref. 100 Copyright 2000 WUey-VCH...

Substrate Characterization. Test coupons and panels of 7075-T6 aluminum, an alloy used extensively for aircraft structures, were degreased In a commercial alkaline cleaning solution and rinsed In distilled, deionized water. The samples were then subjected to either a standard Forest Products Laboratories (FPL) treatment ( 0 or to a sulfuric acid anodization (SAA) process (10% H2SO4, v/v 15V 20 min), two methods used for surface preparation of aircraft structural components. The metal surfaces were examined by scanning transmission electron microscopy (STEM) In the SEM mode and by X-ray photoelectron spectroscopy (XPS). 

The IC, values of the vinca binary alkaloids for microtubule assembly were measured from their concentration-dependent effects on steady-state turbidity levels. Values are presented from two separate experiments. The products induced by a high concentration (10 M) of each compound with MTP or steady-state microtubules assembled from MTP were determined by transmission electron microscopy of steady-state solutions from at least two separate preparations of protein with similar results. SA, Spiral aggregates S, single spirals Am. amorphous aggregates MT, microtubules N.D., not determined. 

In transmission electron microscopy (TEM), a beam of highly focused and highly energetic electrons is directed toward a thin sample (< 200 nm) which might be prepared from solution as thin film (often cast on water) or by cryocutting of a solid sample. The incident electrons interact with the atoms in the sample, producing characteristic radiation. Information is obtained from both deflected and nondeflected transmitted electrons, backscattered and secondary electrons, and emitted photons. 

Hill and Barham [133] showed by transmission electron microscopy that blends of high and low molar mass polyethylene melts were homogeneous with no detectable phase separation. The blends were prepared by solution mixing to obtain an initially homogeneous blend before the thermal treatment in the melt. It should be realised that the mechanical mixing of high and low molar mass linear polyethylenes to obtain a homogeneous melt may require considerable work and time. 

Transmission Electron Microscopy. Films of all samples designated R were obtained by evaporation of toluene from solutions of the block copolymers and were observed without staining using a Hitachi Hu-125 or a JEOL JEM 100 S electron microscope. Methods of preparing the films have been described previously (24). So far, we have obtained evidence for microphase separation in only the four highest molecular-weight samples by TEM. We have not obtained continuous films of the lower molecular-weight samples we plan to examine sections of these samples later. Because of the very small compatibility of styrene and polydimethylsiloxane, however, we expect phase separation in all of these samples. 

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