Characterization by TEM

According to the characterizations by TEM and XRD, the sample prepared from a CH4/H2 plasma was composed of nanocrystalline diamond and disordered microcrystalline graphite. Then nondiamond carbon was effectively removed with an increase in [CO]. It is therefore concluded that the VDOS of the nanocrystalline diamond and DEC films extracted from the HREELS data is in qualitative agreement with the characterizations of TEM and XRD. Although the HREELS probes only the region near the surface, the agreement suggests that the surface dynamics do not differ dramatically from those of the bulk. 

In 1996, Liu et al. reported the selective hydrogenation of cinnamaldehyde, an a,/ -unsaturated aldehyde, to cinnamyl alcohol, an a,/ -unsaturated alcohol, by means of PVP-protected Pt/Co bimetallic colloids prepared by the polyol process [111]. The colloids were obtained as a dark-brown homogeneous dispersion in a mixture of ethylene glycol and diethylene glycol, and characterized by TEM and XRD. These authors prepared different samples of nanoparticles with Pt Co ratios of 3 1 and 1 1, the mean diameters of which measured 1.7 and 2.2 nm, respectively. These colloidal systems were also compared with the single metal-... 

In detail, viral wild-type particles of one set were labeled with the fluorescent dye AlexaFluor (AF) 488 and biotin both groups were attached to surface available lysines. Another batch was labeled with AF568 and biotin, also at addressable lysines. Both types of building block, in the following referred to as CPMV-biotin-AF488 and CPMV-biotin-AF568, were characterized by TEM, UV-visible spectroscopy, native gel electrophoresis, and dot blot studies. TEM studies verified that the particles remained intact after chemical modification. UV-visible spectroscopy confirmed covalent modification and also allowed quantification of the number of labels per particle the particles displayed around 40 biotin moieties and around 200 dyes. 

Sonication of SWCNTs in an aqueous solution of a pyrene-carrying ammonium ion (Fig. 1.13) gave a transparent dispersion/solution of the tubes. The dispersion was characterized by TEM, UV/Vis absorption, fluorescence and 1H NMR spectroscopy and the results evidenced the interaction of the tube sidewalls with the pyrene moiety [212]. 

The nanostructure of nonepitaxially grown Zl0 FePt C thin film was characterized by TEM. As shown in Fig. 36, the bright-field image reveals that FePt grains with uniform size less than 5nm are embedded in the carbon matrix and appear to be well isolated. 

The nanostructure of the double-layered nanocomposite FePt C thin film medium was characterized by TEM. Electron diffraction shows that the crystallites are FePt with the Ll0 structure. Figure 39 shows the bright-field and cross-section TEM image, which verifies that FePt crystallites are imbedded in C matrix and well isolated from each other. 

The knowledge of the structure and the morphology of the metal clusters is necessary if we want to understand the reaction kinetics at the atomic level. The more versatile technique to study the structure and the morphology of supported metal cluster is TEM. It can provide directly the structure and the epitaxial relationships on a collection of clusters in the diffraction mode. By High Resolution TEM it is possible to get this information at the level of one cluster [83]. By using high-resolution profile imaging it is possible to measure the lattice distortion at the interface [84], These capabilities are very unique for TEM. Such structural information can be obtained in situ by diffraction techniques but only on a collection of clusters [14, 29]. To illustrate the structural characterization by TEM we present the case of Pd clusters on MgO(l 0 0), which will be discussed in the next sections. 

By using dendrimers as templates, dendrimer-metal nanoparticles are synthesized in aqueous and non-aqueous media. Particle sizes of metals are significantly affected by many factors including concentration of dendrimers and generation of dendrimers. In particular, structure of dendrimer-metal nanoparticles is characterized by TEM, SANS, and SAXS. 

Undoubtedly the most unlikely substrate for ferritin is U02 +, however, the imphcations of biomimetically synthesizing uranium oxide loaded ferritin could have use in neutron capture therapy. The synthetic approach utilized ion binding of U02(02CCH3)2 according to a known stoichiometry of 12 ions per ferritin molecule, followed by hydrolytic polymerization of metal ions within apo-ferritin. Characterization by TEM analysis confirmed dense cores of polymerized uranyl oxyhydroxide particles of 6 nm in diameter. 

Ferromagnetic Fei-sNis(P) (x=24-65 at.%.) columns have been chemically deposited into porous polycarbonate membranes with pore diameters of 0.1-4 pm. The morphological characterization by TEM reveals the shape features in synthesized columns. Their magnetic perpendicular anisotropy due to the shape anisotropy of columns was observed. 

The Co particles were synthesized by the chemical deposition techniques from C0SO4 7 H2O solutions. The samples were characterized by TEM, X-Ray spectrometry and diffractometiy (DRON - SEIFERT-RM4). For investigation of nearest topological and chemical neighboring of Co atoms the NMR technique was used. The NMR spectra were measured by standard pulse spin-echo... 

When plotted versus crystallite size, independently of the support used, a similar crystallite size effect appears to exist for all three adsorbates— heats of adsorption increase somewhat as crystallite size decreases from 6 nm to below 2 nm. All Pd crystallite sizes were based on hydrogen chemisorption and the assumption of 1. 2 x 10 9 Pdam2-1 (f)). At this time we believe there is a possibility that the values reported for the most poorly dispersed samples—particle sizes of 10 nm and higher—may actually represent a bimodal crystallite distribution because of their preparation by sintering in H2. Consequently, the observed AH(aq) values would be higher than expected for large supported Pd crystallites. Characterization by TEM is now underway to better characterize these catalysts. Further study is necessary to determine the reasons for this apparent crystallite size effect on heats of adsorption, especially since the trend is opposite to that found in supported Pt catalysts (16.1J). 

Aerdts et al. [1997] prepared stabilized PA blends with a functionalized core-shell impact modifier having grafted epoxide groups in the shell. Specifically, 75 parts PA-6 was extraded on a mini-extruder with 25 parts SB core/MMA-GMA shell impact modifier at 240°C. Blends were characterized by TEM. Dispersed phase agglomeration was examined as a function of epoxide concentration on the shell surface. Koulouri et al. 

PPE is not miscible with SMA containing as much as 28% MA [Witteler, et al., 1993]. To compatibilize these two resins, Koning, et al. [1996, 1993b] have added a monoamine-terminated PS that can form a graft copolymer with SMA. Since the amine-terminated PS is miscible with PPE, compatibilized PPE-SMA blends are obtained. Specifically, 30 parts of unfunctionalized PPE was blended (internal mixer at 220°C, mini-SSE at 280°C, or TSE at 326°C) with 56 parts SMA (28% MA) and 14 parts amine-functionalized PS. The blend was characterized by TEM, SEM, mechanical and thermal properties, DMA, and GPC copolymer detection. The effect... 

PA/TPU blends have been compatibilized by addition of a bis-isocyanate coupling agent that is capable of reacting with nucleophilic end-groups on both polymers to form a block copolymer. Franke et al. [1993] have extruded PA-6 (20-0 parts) with polyester-urethane (78-100 parts) using a TSE at 230°C in the presence of 0.5-2 parts diphenylmethane dusocyanate. The coupling agent was added downstream of the extmder feed-throat. The blends were characterized by TEM, SEC, DSC, DMA, and FTIR. 

Ferrocene was incorporated into the templating micelles of synthetic siliceous MCM-41, and found to affect the morphology and structure of MCM-41. Ferrocene was oxidized to tetrahedrally coordinated oxide isolatedly grafted on the pore wall after calcination at 600°C in oxygen, and transformed to oxide nanoparticles in MCM-41 by further heating at 800°C under vacuum, characterized by TEM, in-situ XAS and EPR measurements. 

Bimetallic bifunctional catalysts containing different proportions of Ni and Pt supported in HUSY zeolite were prepared and characterized by TEM, punctual EDX analysis and -hexane isomerization. The EDX analysis of the Ni and Pt bimetallic catalysts shows that the metal particles contain both metals and from HRTEM it was observed that the bimetallic particles have crystallographic parameters of metallic nickel. The presence of small platinum amounts in the nickel catalysts produces more active catalysts for the -hexane isomerization, and presents also higher selectivity for the formation of dibranched hexane than the ones containing only platinum. 

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