SynopsisThe theories of hydrodynamic properties of macromolecules in solutiori leading to an invariant relationship between the values of the intrinsic viscosity, [q], the rr,olecular weight, M, and the translational friction coefficient of the molecule, f; have been considered. The review of experimental data comprising as much as about 2000 fractions of various polymers suggests that for all flexible-chain and moderately rigid-chain molecules the hydrodynamic parameter A, = k q0(M[q]/100)1/3f-1 is actually an invariant independent of the chain length and the thermodynamic strength of the solvent and for moderately polydisperse samples also independent of the degree'of their polydispersity. For polymers with very rigid chains the parameter A , has a high value over the experimentally investigated range of M. These conclusions make it possible to recommend the use of the following average experimental values of the invariant A,, for the determination of M of polymers from the values of [q] and f: for flexible-chain and synthetic polymers with moderately high chain rigidity (3.2 0.2). lO-'O, for polymers with high chain rigidity (3.7 0.4). 1O-Io, and for cellulose derivatives and other polysaccharides with molecular dispersity of nonelectrolyte solutions (3.30 0.30) -lO-'O erg deg-' m01-'/~. The fact that the experimental value of A . = 3.2. lO-'O does not coincide with the value of A erg deg-I mol-1/3 predicted by the theories of translational friction and viscosity of macromolecules implies that the theoretical values of P, = 5.11 and CP, = 2.8 -1023 mol-I are mutually incompatible and these theories require further development. = 3.8 -Hydrodynamic Invariant Both [q] and fare related to the molecular weight M o r the contour length of the chain L = AM/M, by the well-known 7 fractions i.n.s. 13 fractions i.n.s. with M J M , = 1.36 27 fractions i.n.s. with M J M , = 1.4 10 fractions with M J M , = 1.19k0.07 i.n.s. with M J M , = 1.45 8 fractions i.n.s. 12 fractions i n s . 15 fractions with M J M , = 1.16k0.07 M,, = 51,000-762,000 M., = 223,000 M , = 8,500-855,000 M , = 227,000 M , = 9,700-308,000 M , = 77,500 M., = 8,ooO-250,000 Me, = 142,000 M,, = 4,300-305,OOO M,, = 113,000 M,, = 15,90+78,300 M,, = 65,000 Me, = 56,ooO-983,000 M, D = 3359000 M,, = 60,CMlO-813,000 M,, = 470,000 M,, = 25,000-282,000 M,, = 169,000 M,, = 67,000566,000 Me, = 261,000 M,, = 5,500-51,400 M,, = 23,200 M,, = 68,0005,200,000 i.n.s. with M J M , =

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Colloids of metal nanoparticles (NPs) of Au, Ag, Pd, and Pt protected by natural polymer arabinogalactan (ARB) extracted from Larix sibirica were studied. The nanocomposites were prepared by reduction of metal salts in the water solutions of ARB. We carried out dynamic (DLS) and static light scattering resonantly enhanced by the NP plasmons. The translational diffusion was examined via DLS and a polarized interferometer. The virgin ARB was shown to form aggregates in dilute aqueous solutions. The introduction of NPs reduced the size of the virgin ARB aggregates. The aggregate forms as viewed by the scanning electron microscopy support the light scattering results.

The gamma-ray blazar 1611+343 was observed with polarization VLBI mode at 5 GHz in February 1999. The total intensity (I) VLBI image of the source shows a core-jet structure. The jet bends eastward at ∼ 3 mas south of the core. Four components have been detected from results of fitting, with apparent speeds estimated at 6.7 ± 0.7, 2.5 ± 0.3, 4.5 ± 0.5 h −1 c for three jet components (taking H 0 = 100 h km s −1 Mpc −1 , q 0 = 0.5). The polarization (P ) VLBI image of 1611+343 displays the polarized configuration in the jet. The mechanism of the curved jet is discussed.

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