ABSTRACT: Concern about closure of private, rural lands to outdoor recreation has been documented in the research literature for several decades. While many reasons for this phenomenon have been posited, liability for recreational injuries has been identified as a particularly worrisome problem for landowners. However, landowners9 perceptions of liability are not commensurate with the reality of legal risks. This article examines rural landowner liability risks through an analysis of the 50 state recreation-use statutes intended to protect landowners from legal exposure tied to injuries sustained on their land. Further, data from the 637 appellate court cases heard since 1965 involving recreational injuries were compiled and analyzed based on the characteristics of the landowner (public or private), recreation activity pursued at the time of injury, and actual liability exposure. Although the focus of this article is primarily on the liability risks of private landowners and organizations, public agencies also are discussed. Recreation-use statutes are increasingly used in government defense, and cases provide more depth in understanding the reality of landowner liability. Recommendations to agencies concerned with access to private lands and suggestions for future research are included.

AMERICA'S farm, forest, and ranch land faces a crisis of conversion and closure. This crisis may result in the loss of agricultural and forest production as well as the availability of land for outdoor recreation. The latter loss is especially critical because many people propose that recreational use of private land is a partial solution to satisfying America's burgeoning demand for recreational opportunity. Ironically, as more Americans are seeking outdoor experiences, the usable land base is shrinking. In 1962 the Outdoor Recreation Resources Review Commission projected that recreational demand would triple by the year 2000. That projection was surpassed in 1983 (17). Federal, state, and local efforts to acquire more recreational land have not kept pace with those demands. Park visitations increase yearly, causing overuse and degradation of natural resources. The available rural, private landbase also has declined. Urban expansion consumes an estimated 1.5 million acres of agricultural land annually (17). In addition, critical wildlife production and hunting areas, such as wetlands, are being drained or converted to other uses at an estimated rate of 400,000 acres a year (17). Land closure, although different in process than conversion, has the same effect on supply …

Reaction between a reduced solution of cis-[Ru(trien)Br2]Br•2H2O and gaseous nitrogen yields the dimeric species [(trien)RuXN2XRu(trien)]X2 where X = added anion I, Br and trien = triethylene tetraamine. In solution, the halides undergo solvolysis, before bridge splitting occurs, giving the monomeric [Ru(trien)N2H2O]2+ ion. The rate of formation of monomer is pH dependent, being faster in base.

The thermal degradation in vacuum of polymers containing aromatic or heterocyclic rings linked by various groups has been studied by a weight loss method. The most stable of the polymers examined were those with CO, mixed SO2 and O, orSO2 linkages. The stability of these were superior to or comparable with poly-p-phenylene and poly-m-phenylene. The particular combinations of aromatic nuclei and linking groups used did not result in tractability as most of the polymers were insoluble and infusible, even though of low molecular weight. Substitution in the aromatic nuclei could improve tractability, though at the expense of thermal stability.

The thermal degradation in vacuum of a number of halogenated poly(phenylene oxide) polymers has been studied by a weight loss method. In general the thermal stability decreased as the degree of substitution in the phenylene nuclei increased. The chloro derivatives were relatively more stable than the corresponding bromo derivatives. The majority of the polymers showed an initial rapid loss in weight followed by the formation of a highly stable residue. The good thermal stability of the simpler poly(phenylene oxides), coupled with their fusibility and solubility, indicate that they may be useful starting products for the preparation of practical materials.

AbstractThe thermal degradation in oxygen of a number of fluorine‐containing polymers has been studied by using a weight loss technique. The relative thermal stabilities of the different polymers have been determined and, where possible, the overall activation energy and frequency factors for their breakdown. The results have been compared with those for samples of the same polymers degraded in vacuum. There is little change in the relative thermal stabilities observed under both conditions, the fully fluorinated structures being the most stable. The changes in the rates of breakdown in the presence of oxygen are difficult to interpret in the absence of mechanistic information.

AbstractThe thermal degradation in vacuum of a number of fluorine‐containing polymers has been studied by using a weight loss technique. The relative thermal stabilities of the different polymers have been determined and where possible the overall activation energy and frequency factors for their breakdown. The methods of assessment of the weight loss results are discussed. The most stable of the polymers are those which are fully fluorinated.