Reactive composites

The chemical adsorption of a relatively high molecular weight neutral polymer (poly(succinimide), M = 13000) on aminopropyl-Vydac 101 TP silica gel was applied by Alpert [47, 48] to prepare a reactive composite support for use in cation-exchange [47] and hydrophobic-interaction [48] chromatography of pro-... 

Therefore, the initial choice for an oxidizer is one with an exothermic heat of decomposition such as potassium chlorate (KCIO 3). However, mixtures of both chlorate and perchlorate salts with active metal fuels are too ignition-sensitive for commercial use, and the less-reactive - but safer - nitrate compormds are usually selected. Potassium perchlorate is used with aluminum and magnesium in some "photoflash" mixtures these are extremely reactive compositions, with velocities in the explosive range. 

When preparing coatings from reactive compositions, a thin layer of material is first applied to the item. The coating material adheres to the item by gravitational, magnetic, centrifugal or adhesion forces. The prepared article with its reactive layer is then placed in a chamber where the final polymeric coating is formed. 

Notation To is the initial temperature of the reactive composition Tm is the mold temperature t is solidification (curing) time Qp is the heat of polymerization U is the apparent activation energy of the chemical reactions Sh is shrinkage... 

Several explosive incidents, mostly of academic origins, have appeared in which violently reactive compositions have been assembled at liquid nitrogen temperatures and then removed from the bath and allowed to warm up, in the hope of a moderated reaction. Solids do not react with each other, and solutes often crystallise on cooling, even when any solvent remains liquid, thus locally concentrating the reagents. This procedure offers scant cooling or control as solids melt and react. In the most extreme cases, one or more of the reactive, but unreacted, solids was actually a gas at ambient temperature, and rapidly resumed... 

In addition to these single-phase hydrides multiphase mixed hydrides or so-called reactive composites attract increasing attention. By addition of another element or compound the reaction enthalpy of the hydride can be tailored very efficiently if a stable compound is formed from the hydride and the additive(s) upon desorption. Unfortunately, this approach leads to an unwanted decrease in hydrogen storage capacity. 

Concentrated low-formaldehyde reactant, highly reactive Composition Modified glyoxal based resin Typical properties ... 

As fluxes for MEM of titanium, the reactive compositions on the base of halogenides of alkali and alkali-earth metals are used. Halogenide fluxes allow the electroslag process to be easily set and provide its stability within the wide range of melting conditions. Rate of dissolution of harmful inclusions of nitrides of titanium in these fluxes much exceeds their rate of dissolution in molten titanium [4], Thus, the premises for dissolution and grinding of hard a-phase type inclusions are created. 

Cellulose acetate is compatible with cellulose nitrate, but little benefit has resulted from using the two together in a coating composition. Limited use has been made of cellulose acetate in reactive compositions even though it is compatible with urea-formaldehyde resins. 

While high isotope conversion factors are desirable in many instances, in other cases simplicity of construction and care of handling the materials involved can be more important. The present application is therefore primarily directed toward the provision of a simply constructed 60 isotope converter wherein the active materials are in solid form, can be easily cooled in place, and easily re-mov for processing, and replaced with fresh material. It will be understood that the selection of fissionable materials, moderator materials and fertile materials, the 65 relative amounts thereof and the critical size of the reactive composition required to produce a self-sustaining chain reaction, are not in themselves the subject of the present invention. These criteria are now familiar to persons skilled in the art The invention is concerned 70 with a novel construction which may be employed with any of the various combinations of materials which are already well known. 

Anoher object of the invention is to provide a simple and sensitive means for controlling the neutronic reaction while at the same time producing a useful material by subjecting neutron absorbent material to intense neutron bombardment. This object is accomplished by dividing the reactor into a plurality of sections or cells, the central group of which comprises reactive composition between spaced portions of fertile material, and the outer group of cells comprises fertile material only. Thus a reactive zone is provided which is completely surrounded by an absorption zone of the particular fertile... 

The present invention relates to nuclear physics and more particularly to an improved means and method of cooling a reactive composition used to sustain a chain fission reaction. 

It is therefore an object of the present invention to provide a novel means and method of circulating and cooling the reactive composition of a liquid type neutronic reactor without the use of rotating pumps. 

In neutronic reactors operating at high neutron densities, radioactive elements of exceedingly high capture cross-section are formed relatively quickly in the reactive composition as an intermediate element in the decay chains of the fission fragments. One of the most important of these decay chains is believed to be the 135 fission chain starting with tellurium, as follows ... 

Hie pulsating method of cooling a reactor having a liquid reactive composition can also be applied to a reactor using natural uranium. When a uranium oxide slurry is used as the reactive composition, typical data is as follows ... 

The method of cooling the fluid reactive composition of a neutronic reactor which comprises cyclically oscillating the reactive composition through a chain reaction zone while maintaining a sufficient amount of the reactive material in the reaction zone to maintain the chain reaction. 

The method of cooling a fluid neutronically reactive composition which comprises establishing a chain reaction in said fluid within a reaction zone, cyclically moving said fluid in a reciprocative manner out of and back into said zone by application of gas pressure thereto while maintaining a chain reaction within said zone, and cooling said fluid while moving it out of and back into said zone. 

A method of cooling a body of fluid reactive composition in a neutronic reactor comprising oscillating a portion of said composition between a reaction tank and a heat exchange device connected thereto by sub-... 

In a neutronic reactor, a chamber, a plurality of heat exchangers externally thereof and independently connected thereto, a body of fluid neutronically reactive composition capable of sustaining a thermal nuclear chain reaction, and means for alternately pulsating said composition between said chamber and respective heat exchangers without reducing the mass of said body below the critical size at which the same is capable of sustaining said reaction. 

In a system of the class described, a reaction chamber, a pair of pressure chambers having independent connections thereto, means in said system for sustaui-ing a thermal nuclear chain reaction comprising reactive composition in said reaction chamber including thermally fissionable material and liquid neutron moderator, and means for withdrawing from said composition the gaseous products of nuclear reactions therein, said Ulst-men-... 

The reactive composition within the tank 10 is replenished and renewed as desired by means of a make-up line 37 and a drain line 38 communicating with the bottom of the tank 20. 

A neutronic reactor system according to claim 1 v/herein the reactive composition completely fills the herical container. 

As illustrated in FIG. 1 the reactor is in the form of two hemispheres, each comprising a hemispherical core of the reactive composition 2 and an outer hemispherical reflector or blanket 4 of uranium contained within re-... 

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