9 research outputs found
Connecting the vulcanization transition to percolation
The vulcanization transition is addressed via a minimal
replica-field-theoretic model. The appropriate long-wave-length behavior of the
two- and three-point vertex functions is considered diagrammatically, to all
orders in perturbation theory, and identified with the corresponding quantities
in the Houghton-Reeve-Wallace field-theoretic approach to the percolation
critical phenomenon. Hence, it is shown that percolation theory correctly
captures the critical phenomenology of the vulcanization transition associated
with the liquid and critical states.Comment: 9 pages, 5 figure
Conformations of Randomly Linked Polymers
We consider polymers in which M randomly selected pairs of monomers are
restricted to be in contact. Analytical arguments and numerical simulations
show that an ideal (Gaussian) chain of N monomers remains expanded as long as
M<<N; its mean squared end to end distance growing as r^2 ~ M/N. A possible
collapse transition (to a region of order unity) is related to percolation in a
one dimensional model with long--ranged connections. A directed version of the
model is also solved exactly. Based on these results, we conjecture that the
typical size of a self-avoiding polymer is reduced by the links to R >
(N/M)^(nu). The number of links needed to collapse a polymer in three
dimensions thus scales as N^(phi), with (phi) > 0.43.Comment: 6 pages, 3 Postscript figures, LaTe
The application of MELODY to control unpenetrated weldpools
SIGLEAvailable from British Library Document Supply Centre- DSC:7761.039(RD/M--1796/RR89) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
A method for measuring small vibrations with a laser
SIGLEAvailable from British Library Document Supply Centre- DSC:3106.13387(TPRD/M--1608/R87) / BLDSC - British Library Document Supply CentreGBUnited Kingdo