Particles, isolation

The hydrosilylation of nitriles is unusual, since the cyano group is quite inert under the usual reaction conditions [37]. Rhodium metal particles, isolated as rmsupported (catalyst B) or supported (catalyst C) samples are able to catalyze the hydrosilylation of aromatic nitriles to N,... 

A reduction in conductance of portions of the cathode can easily explain the observed increase in cell impedance as well as loss of cathode capacity via isolation of oxide active material. Particle isolation is also in concert with our observations of carbon retreat or rearrangement in tested cathodes. These results represent the most clear and obvious difference (compared to other diagnostic studies) in cathode characteristics after prolonged cell tests at elevated temperatures. 

FIGURE 1.1. Schematic drawing of the dendrimer-assisted preparation of uniform-sized metal particles. Metal ions (Mn+) are first complexed to a 4th generation OH-terminated poly(amidoamine) dendrimer. Then the metal ions are reduced to a metal particle, isolated from other metal particles. 

Fig. 6. Purified recombinant HMGA proteins bind to four regions of DNA on random sequence nucleosome core particles. Panel A The results of EMSA gel assays in which increasing concentrations of either purified nonhistone HMGN2 (a.k.a., HMG-17, which binds to two sites on nucleosome core particles) or recombinant human HMGAla protein were bound nucleosome core particles isolated from chicken erythrocytes [57]. Panel B Two different views of the nucleosome taken from the X-ray structure of Luger et al. [119] showing the sites of binding of HMGA proteins (dashed circles) determined by DNA foot-printing analyses and other techniques (see text for details).

Compartmentalization (or segregation) of a propagating radical in a polymer particle isolates it from other propagating radicals and allows growth to higher molecular weight than might be achieved in solution polymerization, provided that the rate of entry of another radical from the aqueous phase is sufficiently slow. 

Similarly, concern about minute amounts of contaminants co-purified with human growth hormone extracted from brain tissues, which could lead to the development of Jacob-Kreutzfeld syndrome, inevitably resulted in the development of recombinant human growth hormone. Inactivated hepatitis B particles isolated from hepatitis B-positive patients were originally used to prevent hepatitis B virus infection, but a small fraction of individuals became infected through vaccination. When the hepatitis B surface antigen was... 

Allison, S.D., Molina, M.C., Anchordoquy, TJ, (2000). Stabilization of lipid/DNA complexes during the freezing step of the lyophilization process the particle isolation hypothesis. Biochim. Biophys. Acta, 1468, 127-138. 

Wright, J.F., Kurosky, A., Pryzdial, E.L., and S. Wasi, 1995, Host cellular annexin II is associated with cytomegalovirus particles isolated from cultured human fibroblasts. J Virol. 69(8) 4784-91. 

T. Ohno, K. Sarukawa. and M. Matsumura, Photocatalytic activities of pure rutile particles isolated from Ti02 powder by dissolving the anatase component in HF solution, J. Phys. Chem. B 105, 2417-2420 (2001). 

Matsunaga, T., and Kamiya, S., Use of magnetic particles isolated from magnetotactic bacteria for enzyme immobihzation, AppZ. Microbiol. BiotechnoL, 26,328, 1987. 

The lipid-soluble antioxidants present in the LDL particle are responsible for the LDL particle resistance to oxidation [3]. LDL copper-mediated oxidability in vitro, has been used by several researchers to evaluate oxidation resistance of LDL. LDL oxidation is evaluated by following in vitro copper-mediated oxidation of LDL [3,49]. Duration of the lag phase determines the resistance of LDL to oxidation and depends on the content of antioxidants in the LDL molecule. During the lag period, the alpha-tocopherol and other antioxidants are lost from LDLs. The length of the lag phase reflects the protective effects of chain-breaking antioxidants, especially alpha-tocopherol. When LDL particles, isolated from subjects who have consumed vitamin E supplements, or are enriched with vitamin E, the length of lag period is significantly increased [3]. 

Reviews (9, 63, 64) of the reactions between hydroxylated mineral surfaces and aqueous solutions brought out the richness of variety found in surface phenomena involving natural particles. Isolated surface complexes, the principal topic of this chapter, are expected when reaction times are short and the adsorbate content is low [Figure 6, inspired by Schindler and Stumm 63)]. Thus, surface complexes occupy a reasonably well-defined domain in the tableau of reaction time scale versus sorbate concentration. Localized clusters of adsorbate (47, 48, 65, 66) that contain two or more adsorbate ions bonded together can form if the amount sorbed is increased by accretion or bv the direct adsorption of polymeric species (multinuclear surface complexes). Surface clusters can erase the hyperfine structure in the ESR spectrum of an immobilized adsorbate (33, 67) or produce new second-neighbor peaks from ions like the absorber in its EXAFS spectrum (47, 66). 

Figure 3. Transmission electron micrograph (replica) of Pt particles isolated from the Pt(th)/Ti02 film annealed in argon at 550°C.

DETronrud, MF Schmid and BW Mathews (1986) Structure and x-ray amino acid sequence of a bacteriochlo-rophyll a protein from Prosthecochloris aestuarii refined at 1.9 resolution. J Mol Biol 188 443-454 T Katoh, M MImuro and S Takalchl (1989) Light-harvesting particles Isolated from a brown alga, DIctyota dichotoma. A supramolecular assembly of fucoxanthin-chlorophyll-protein complexes. Biochim Biophys Acta 976 233-240... 

Fig 6. Absorption and second-derivative spectra of intact fucoxanthin-chlorophyll- a/c protein assembly (FCPA) at room temperature (A, top) and 77 K (A, bottom). Absorption spectra of intact and Triton-treated FCPA (B, top) and their difference spectrum between the two (B, bottom). Figure source Katoh, Mimuro and Takaichi (1989) Light-harvesting particles isolated from a brown alga, Dictyota dichotoma. A supramolecular assembly of fucoxanthin-chlorophyll-protein complexes. Biochim BiophysActa 968 236,237. 

T Katoh, M Mimuro and S Takaichi (1989) Light-harvesting particles isolated from a brown alga, Dictyota dichotoma. A supramolecular assembly of fucoxanthin-chlorophyll-protein complexes. Biochim Biophys Acta 976 233-240... 

Fig. 2. (A) Flash-induced absorbance changes at 367 nm in PS-II particles isolated from Synechococcus at pH 7 and in the presence of 2X10 M silicomolybdate, (B) Spectra produced by each of four consecutive flashes in PS-II particles containing silicomolybdate. Figure source Saygin and Witt (1987) Optical characterization of intermediates in the water-splitting enzyme system of photosynthesis - possible slates and configuration of manganese and water. Biochim Biophys Acta 893 456, 457.

B Ke, K Sugahara and ER Shaw (1975) Further purification of Triton Subchloroplast fraction I (TSF-I particles). Isolation of a cytochrome-free high-P700 particle and a complex containing cytochromes f and b, plastocyanin and iron-sulfur protein s). Biochim Biophys Acta 408 12-25... 

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