Photolysis of spacecraft contaminants

A molecular beam facility, which was designed to measure photochemical cross-sections, has been constructed at the Athens College science facility. The integration of this vacuum system into an operational photochemical instrument was performed with signal processing consisting of both dc and ac techniques. Of the experiments performed to date on the vacuum ultraviolet photolysis of water vapor, it is apparent that a larger pumping capacity (preferably with differential pumping) is required to improve upon the background signal. Both phase-sensitive detection and ion-counting techniques are recommended for future studies

Occurrence and Behavior of Juvenile Red Snapper, Lutjanus campechanus, on Commercial Shrimp Fishing Grounds in the Northeastern Gulf of Mexico

Red snapper, Lutjanus campechanus, is subject to significant overfishing in U.S. Gulf of Mexico waters, and regulations are being implemented to reduce fishing mortality and restore them to a 20% spawning potential ratio by the year 2009. One source of mortality that must be reduced to achieve this goal is the incidental capture ofjuvenile red snappers in shrimp, Penaeus spp., trawls. NOAA's National Marine Fisheries Service is conducting research to develop shrimp trawl modifications to reduce the snapper bycatch. An important part of this research is the study of juvenile red snapper behavior on commercial shrimp grounds and in relation to trawling gear. An area of high juvenile red snapper abundance was identified off the coast of Mississippi. Most snappers were observed around structures or objects on the bottom which they appeared to use for refuge or orientation. Those ranging over barren bottom had no apparent point of orientation. When encountered by shrimp trawls, most juvenile snappers rose above the trawl footrope and fell back into the trawl. These observations have directed research toward modifying shrimp trawls to release juvenile red snappers after entry, rather than preventing them from entering a shrimp trawl

The feasibility of low-G grey solidification of nodular iron in the F-104 experimental furnace package

The rationale for low-g experiments with cast iron and the need for solidification in the grey form during these experiments are reviewed. The factors which determine whether an iron melt will solidify grey or white are discussed. Cooling rate versus microstructure was studied for a nodular iron candidate material for F-104 low-g solidification. The study determined that low-g grey solidification, using the present F-104 furnace system, of the nodular iron composition studied is not feasible. Specimen microstructure strongly suggested that the F-104 furnace's gas cooling system was causing excessive localized chill resulting in the nucleation of the unwanted iron carbide phase. A change is suggested, in the quench system design, that could possibly overcome this problem

Feasibility demonstration for hydrogen chloride detection using a chemisorption technique and a quartz crystal microbalance

A method of measuring concentrations of hydrogen chloride between 1 part per billion and 10 parts per million at standard temperature and pressure is presented. The feasibility of a low-cost device incorporating a chemisorption technique coupled with a quartz crystal microbalance was demonstrated in the field at the Viking B launch using a Titan-Centaur vehicle from Kennedy Space Center on August 20, 1975. Hydrogen chloride is a product of solid rocket combustion. The concentration level of hydrogen chloride for this particular launch was measured as approximately 0.2 parts per million at 4 km from the launch site

Eddy current inspection of graphite fiber components

The recognition of defects in materials properties still presents a number of problems for nondestructive testing in aerospace systems. This project attempts to utilize current capabilities in eddy current instrumentation, artificial intelligence, and robotics in order to provide insight into defining geometrical aspects of flaws in composite materials which are capable of being evaluated using eddy current inspection techniques. The unique capabilities of E-probes and horseshoe probes for inspecting probes for inspecting graphite fiber materials were evaluated and appear to hold great promise once the technology development matures. The initial results are described of modeling eddy current interactions with certain flaws in graphite fiber samples

Space processing of electronic materials

The relative values of thermal conductivity of solid and liquid HgCdTe are critically important in the design configuration of the furnaces used for Bridgman crystal growth. The thermal diffusivity of the material is closely linked to the conductivity by the defining relation D = k/rho c, where D is the diffusivity, K is the thermal conductivity, rho is the density, and c is the specific heat. The use of transient and periodic heating approaches to measure the diffusivity are explored. A system for securing and extracting heat from silica or glass tubes under high C vacuum conditions is described

Toward the Integration of Economics and Outdoor Recreation Management

The general theme of this bulletin is that improved management of public-sector recreational resources is a multidisciplinary task. To this end, we attempt to integrate elements of outdoor recreation management theory and economics. The bulletin is written for both resource managers and researchers. For the former, our intent is to emphasize the importance of being aware of economic implications-at least conceptually-of management actions that influence the character and availability of recreational opportunities. To researchers involved in developing recreation management theory, we draw attention to the parallel between recreation management theory and the traditional managerial economic model of the firm. To economists, particularly those involved in developing and applying nonmarket valuation techniques, we draw attention to the types of decisions faced by resource managers. We argue that the most important resource allocation issues are of the incremental variety, so nonmarket valuation should also yield incremental values. These values alone, however, are not sufficient economic input into rational public choice analysis. The missing link , or nexus, between outdoor recreation management theory and economic analysis is the integration of supply and demand, as called for by traditional managerial economics. Collaborative research to develop recreation supply response functions akin to agricultural production functions is an essential step that is missing from both literatures. Theoretical and applied work assume greater practical importance if they feed information into this broadened framework. It is our hope that this bulletin will bring the disciplines closer to that realization

Participation, Preferences, and Characteristics of Outlying-Cabin Users in Alaska National Forests

The development and management of public-use cabins have been planned, or at least considered, by several federal and state agencies in Alaska. This bulletin reports the results of a pilot study of the cabin program of the U.S. Forest Service. There are problems of aggregated data which did not allow for detailed analysis; however, the report does provide an overview of the Forest Service outlying cabin program-who uses it, how they use it, and how they feel about it. The manager should be careful in applying the results without consideration of the total recreational spectrum, i.e., where the cabin program fits within this spectrum, and its cost in terms of other recreation opportunities that may be specified. It is the opinion of the authors that it would be unwise to simply mass reproduce the outlying cabin program in all areas having periods of inclement weather. The study sampled only cabin users-not all users or potential users of the particular landscape setting. To over-emphasize an expanded cabin program would reduce the continuum of opportunities. While subsequent studies of the cabin user population would likely find this group to prefer the new program, the users who did not prefer it or who were unwilling to adopt to new conditions would have been displaced. Thus, while the results have some direct applicability, it is also important to consider the maintenance of the continuum of recreational opportunities, only one portion of which is covered by outlying cabins

Non-Market Valuation of Open Space and Other Amenities Associated with Retention of Lands in Agricultural Use

The most productive farmland in southcentral Alaska is currently under intense development pressure due to rapid population increases and consequential increases in demand for suburban housing. This study utilizes a contingent valuation iterative bidding game to estimate the willingness of Matanuska-Susitna Borough residents to pay to preserve open space and other historical/environmental amenities associated with farming activities. Determinants of consumer behavior are addressed as well as total benefits and costs of various posited development scenarios. This information may be useful to policymakers assessing actions designed to purchase development rights from Matanuska-Susitna farmers

AN EXAMINATION OF A DEVELOPMENT RIGHTS PURCHASE PROGRAM FOR ALASKA AGRICULTURAL LANDS

A report submitted to the Department of Natural Resources, State of Alaska, in accordance with terms of research contract OCTO 1142.Many Alaskans are concerned about the conversion of highly productive agricultural lands to nonagricultural uses now occurring in the state. Land on the urban fringes of Anchorage and Fairbanks that once produced vegetables and grains or supported dairy farms appears most vulnerable to this conversion. As major population centers grow, residential, shopping center and industrial land uses displace agriculture because they render greater returns. This displacement is viewed by some as not being in society's best interest. Those concerned about the loss of agricultural lands argue that these lands are some of the best agricultural lands in the state and are vital to maintaining the agricultural economy of the state. In addition, it is suggested that their preservation will help to maintain a much desired way of life and to provide needed open space. The state and municipal governments in Alaska have made attempts to intervene in the land market to slow down or stop agricultural land conversion. Methods employed to date include tax incentives and the sale of only the agricultural rights on state or municipal lands. This report discusses the feasibility of an alternative means of preserving agricultural lands, namely, the public purchase of development rights from private landowners. Under this voluntary arrangement, private agricultural landowners would be compensated for giving up their option to develop their land for nonagricultural purposes.Introduction: Overview, Plan of Report -- Market Failure and the Allocation of Agricultural Land Resources -- Agricultural Land Conversion in Alaska -- Present and Potential Agricultural Development in Alaska: Introduction, Present Agricultural Situation, Agricultural Lands for Future Development, Future Agricultural Development in Alaska -- Purchase of Development Rights: Suffolk County: History, Maryland, New Jersey, Massachusetts and Connecticut, Definition of Development Rights, Strengths and Weaknesses of Development Rights Purchases -- Applicability of a Development Rights Program in Alaska: Introduction, Development Rights Survey in Alaska: Response, Farm Size of Respondents, Interest in Selling Development Rights, Market Values of Cleared and Uncleared Agricultural Lands, Value of Development Rights, Distance from a Population Center, Interest in Selling Development Rights, and Perceived Value of Development Rights -- Economic Size Agricultural Operations -- Potential Costs of a Purchase of Development Rights Program: Other Costs -- Benefits of Development Rights Acquisition: Maintenance of the Local Agricultural Economy, Locally Produced Food, Open Space and Other Public Good Amenities, Removal of Uncertainty -- Other Agricultural Land Control Tools: Comparison of Agricultural Land Preservation Tools -- Summary and Conclusions -- References -- Appendix A: Operation of of Purchase of Development Rights Programs -- Appendix B: Alaska Agricultural Lands Survey -- Appendix C: Additional Comments from Respondents -- Appendix D: Alternative Agricultural Land Control Technique