Star-burst

Star-burst polyamidoamine (PAMAM) dendrimers with primary amine end groups in d-methanol [306] and with hydroxyl or glucopeptide end groups in D2O [307] have been investigated by NSE in order to identify internal segment... [Pg.186]

Figure 4.4 shows shell stars bursting above fans of Roman candles. [Pg.66]

Figure 4.8 Bouquet shells with star burst eflfects.

Chen ZY, Cui S-M. Monte Carlo simulations of star-burst dendrimers. Macromolecules 1996 29 7943-7952. [Pg.298]

Fig. 29. Computer simulated molecular graphics (wireframe) using POLYGRAF for STAR-BURST (polyether) dendrimers of generations 1-4...

A typical aerial shell used in fireworks displays. Time-delayed fuses cause a shell to explode in stages. In this case a red star-burst occurs first followed by a blue starbursb and finally a flash and loud report. Reprinted with permission from Chemical Engineering News, Vol. 59, Issue 26, June 29,1981, p. 25. Copyright 1981 American Chemical Society. [Pg.524]

The collared earthstar Geastrum triplex) grows out of the forest floor. This species has a bulbous spore-case, surrounded by pointed, ray-like structures that gives an overall appearance of a star-burst. [Pg.462]

Tomalia, D.A. Naylor, A.M. Goddard, W.A., III. Star-burst dendrimers molecular-level control of size, shape, surface chemistry, topology and flexibility in the conversion of atoms to macroscopic materials. Angew. Chem. Int. Ed. 1990, 29, 138-175. [Pg.887]

Roberts, J.C. Bhalgat, M.K. Zera, R.T. Preliminary biological evaluation of polyamidoamine (PAMAM) star-burst dendrimers. J. Biomed. Mater. Res. 1996, 30, 53-65. Malik, N. Wiwattanapatapee, R. Klopsch, R. Lorenz, K. Frey, H. Weener, J.W. Meijer, E.W. Paulus, W. Duncan, R. Dendrimers relationship between structure and biocompatibility in vitro, and preliminary studies on the biodistribution of l-Labeled polyamidoamine dendrimers in vivo. J. Control. Release 2000, 65, 133-148. [Pg.890]

Qin et al. (238) used starburst PAMAM dendrimers to transfer genes into a murine cardiac transplantation model. These star-burst dendrimers are a special class of its kind, which are highly branched spherical polymers... [Pg.668]

The localization of counterions in the intramolecular volume is a common feature manifested in dilute salt-free solutions of branched polyions of different topologies, including dendritic (star-burst), randomly (hyper)branched PEs, PE molecular brushes, etc. The physical reason for this phenomena is the same as outlined for PE stars a strongly charged, branched, macroion creates a high electrostatic potential, which attracts counterions and retains them in the intramolecular volume, in spite of a significant loss in the translational entropy. The effect is most pronounced in a dilute solution, where the concentration of counterions in the bulk is extremely low. [Pg.20]

The conformations of charged (regular) star-burst polymers (flexible ionic dendrimers), were analyzed theoretically in [33]. Referring to Fig. 4a, relevant architectural parameters for a star-burst polymer are the number of generations. [Pg.20]

Hence, counterion localization occurs when the number of generations in the star-burst polymer, g log2(Af/n), reaches some characteristic value, which is controlled by the same combination of the parameters, as for a PE star. [Pg.21]

Star-burst Oxadiazole Polymers. When a 1,3,5-trifunctional monomer is introduced in the synthesis (Scheme 8), a highly branched or star-burst polymer, or even a crosslinked polyaromatic oxadiazole may be expected to form according to the ratio of the monomers (45). A 1 1 1 ratio of 26 27 28 has been chosen to form a star-burst polyaromatic oxadiazole polymer 29. [Pg.336]

Scheme 8. Synthesis of a star-burst polyaromatic oxadiazole polymer 29 (adapted from 45)...

Fig. 2.1.3a-f. Various radiofrequency (RF) electrodes a single needle design (Cool Tip, Valleylab System, Tyco), b cluster-electrode (Cool Tip Cluster, Valleylab, Tyco) multi-tined electrodes (c LeVeen, Radiotherapeutics, Boston Scientific d Star-burst XL e perfused Talon needle, AngioDynamics-RlTA) f internally cooled, bipolar single needle electrode (Olympus Celon)... [Pg.11]

Fines are always in your system. Fines do not melt at the same melting temperature as your virgin resin or your regrind. Their molecular weights are different. Fines should always be eliminated. Fines can clog your dryers, cause streaks, star bursts, black specks, and tear drops in your blown product. [Pg.272]

Sumby CJ, Hardie MJ (2005) Capsules and star-burst polyhedra an [AgiLj] capsule and a tetrahedral [Ag4L4] metallosupramolecular prism with cyclotriveratrylene-type ligands. Angew Chem Int Ed 44 6395-6399... [Pg.415]

Sumby CJ, Carr MJ, Franken A, Kennedy JD, Kilner CA, Hardie MJ (2006) Crystal-packing motifs of [Ag4l ] star-burst tetrahedra. New J Chem 30 1390-1396... [Pg.415]

Ronson TK, Fisher J, Harding LP, Httfdie MJ (2007) Star-burst prisms with cyclotriveratrylene-type ligands a [Pd Lg] steUa octangular structure. Angew Chem Int Ed 46 9086—9088... [Pg.415]

Fullerene-derived star-burst conjugated polymers have been prepared by nucleophilic substitution of the tertiary NO2 groups (used as good leaving groups) of the hexanitrofullerene C6o(N02)6 with aniBne, oUgoanUine, and polyanduie [108,109],... [Pg.121]

OH mega-masers within the central 100 pc of nuclear star-burst regions. [Pg.179]

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