23,918 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
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
Imidazopyrrolone/imide copolymers Patent
Synthesis and chemical properties of imidazopyrrolone/imide copolymer
Dosimeter for high levels of absorbed radiation Patent
Development of dosimeter for measuring absorbed dose of high energy ionizing radiatio
Surface location of alkaline-earth atom impurities on helium nanodroplets
There has been notable uncertainty regarding the degree of solvation of
alkaline-earth atoms, especially Mg, in free He-4 nanodroplets. We have
measured the electron energy dependence of the ionization yield of picked-up
atoms. There is a qualitative shape difference between the yield curves of
species solvated in the middle of the droplet and species located in the
surface region; this difference arises from the enhanced role played by the
Penning ionization process in the latter case. The measurements demonstrate
that Mg, Ca, Sr and Ba all reside at or near the droplet surface.Comment: 11 pages, 3 figure
- …