55,643 research outputs found
Process for interfacial polymerization of pyromellitic dianhydride and 1,2,4, 5-tetraamino-benzene Patent
Process for interfacial polymerization of pyromellitic dianhydride and tetraamino benzen
On Electrogravity Duality
By resolving the gravitational field into electric and magnetic parts, we
define an electrogravity duality transformation and discover an interesting
property of the field. Under the duality transformation a vacuum/flat spacetime
maps into the original spacetime with a topological defect of global
monopole/texture. The elctrogravity-duality is thus a topological defect
generating process. It turns out that all black hole solutions possess dual
solutions that imbibe a global monopole.Comment: 9 pages, LaTeX versio
Polymer film exhibits thermal and radiation stability
Aromatic/heterocyclic polymers /Pyrrones/ have the ability to absorb large quantities of photolytic, thermal and radiolytic energies while retaining their useful properties. They are prepared from the room temperature reaction of tetraamines and tetraacids
Source of released carbon fibers
The potential for the release of carbon fibers from aircraft crashes/fires is addressed. Simulation of the conditions of aircraft crash fires in order to predict the quantities and forms of fibrous materials which might be released from civilian aircraft crashes/fires is considered. Figures are presented which describe some typical fiber release test activities together with some very preliminary results of those activities. The state of the art of carbon fiber release is summarized as well as some of the uncertainties concerning accidental fiber release
Potential release of fibers from burning carbon composites
A comprehensive experimental carbon fiber source program was conducted to determine the potential for the release of conductive carbon fibers from burning composites. Laboratory testing determined the relative importance of several parameters influencing the amounts of single fibers released, while large-scale aviation jet fuel pool fires provided realistic confirmation of the laboratory data. The dimensions and size distributions of fire-released carbon fibers were determined, not only for those of concern in an electrical sense, but also for those of potential interest from a health and environmental standpoint. Fire plume and chemistry studies were performed with large pool fires to provide an experimental input into an analytical modelling of simulated aircraft crash fires. A study of a high voltage spark system resulted in a promising device for the detection, counting, and sizing of electrically conductive fibers, for both active and passive modes of operation
Modelling for research on chemical control of mammals in New Zealand
Development of predictive formulae or qualitative statements about the probable outcome of control campaigns entails knowledge of bait quality and distribution, behaviour, vagaries of weather at the time of the control campaign, and other factors which govern the probability that the target animals will accept bait. This paper collates experience in recognising, estimating and using some of these variables for predicting the outcome of large-scale poisoning, and discusses possible approaches to the solution of some hard-core problems
A simultaneous generalization of independence and disjointness in boolean algebras
We give a definition of some classes of boolean algebras generalizing free
boolean algebras; they satisfy a universal property that certain functions
extend to homomorphisms. We give a combinatorial property of generating sets of
these algebras, which we call n-independent. The properties of these classes
(n-free and omega-free boolean algebras) are investigated. These include
connections to hypergraph theory and cardinal invariants on these algebras.
Related cardinal functions, Ind, which is the supremum of the cardinalities
of n-independent subsets; i_n, the minimum size of a maximal n-independent
subset; and i_omega, the minimum size of an omega-independent subset, are
introduced and investigated. The values of i_n and i_omega on P(omega)/fin are
shown to be independent of ZFC.Comment: Sumbitted to Orde
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