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Extraterrestrial disposal, while not the only alternative (there is at least one very safe terrestrial method), nevertheless assures definite and irreversible removal of the most toxic and long-lived waste from the biosphere. In the foreseeable future, there is far less need to retrieve nuclear waste for later use then to dispose of it in a publicly acceptable manner, beginning in the near future (middle 1980s). It is, therefore, more important to assure safety in the weakest link of this disposal process—transportation into near-Earth orbit—than to engage in a retrievable disposal beyond Earth. The disposal “site” should lie at minimum safe transfer energy level. Primary candidate is the space between Venus and Earth. The number of propulsion phases should be a minimum, preferably only one (out of near-Earth orbit). Lunar gravity assist can be helpful to achieve higher inclination of the heliocentric orbit relative to the ecliptic.Solidified spent fuel isotopes and actinides, sufficient to reduce the residual terrestrial waste to the radiation level of natural uranium deposits after 30–40 yr instead of 1000–1500 yr, is deposited into heliocentric orbits. Transportation systems, requirements, costs and the associated socio-economic benefit potentials of an environmentally more benign and a more vigorous nuclear power generation program are presented.Prior to solidification, an interim storage of 10 yr, following removal from the reactor, may be required. The Shuttle, with one Orbiter modified as Nuclear Waste Carrying Orbiter (NWCO) and an out of near-Earth orbit booster, provides a safe and economic transportation system at (1979$) disposal mission costs from surface to disposal orbit of less than 0.5¢/kWhe or ? 0.1¢/kWhe (some 70% of overall exo-disposal cost), depending on level of orbital operations (this at basic Shuttle flight cost of $30M). The orbital operations mode can be selected according to lead time and costs, and can be advanced sequentially, lowering disposal costs while at the same time financing the development of orbital operations techniques needed also for other and larger-scale exo-industrial activities. An average of 10–15 disposal missions of the NWCO is required annually, at the given conditions, to service the spent fuel of 173 reactors 1978 in operation in W. Europe, Japan and North America.  相似文献   
2.
基于我国飞机结构疲劳强度测试系统的实际情况,结合目前网络技术在工业领域中的应用,提出了一种基于以太网的远程控制型分布式应变测试系统,着重论述了采用以太网技术实现多个远程监控端和测试端之间的通信,通过实验验证了命令和数据传输的可靠性与实时性。  相似文献   
3.
在乙醚-甲苯混合溶剂中,苄基氯和LiAlH4反应生成AlH3乙醚络合物。此络合物在甲苯介质中脱醚得到α-AlH3。通过X射线衍射、元素分析、扫描电镜及热分析,对样品进行表征。测试结果表明,此方法得到的α-AlH3晶体纯度高,Cl含量低,形貌完整,颗粒均匀,产物的热力学性能优良。  相似文献   
4.
Geosocio-economically useful lunar development requires adoption of a development strategy designed to balance investments and returns as attractively as possible. This paper deals with a systematic approach to developing early and profitable returns through an appropriate investment strategy and through cislunar and terrestrial market research. In addition, long-term aspects are outlined, including the production of helium-3 for terrestrial fusion power plants and of water from fusion products and lunar oxygen.  相似文献   
5.
The paper discusses two methods for lunar surface access. One method is characterized by very little propellant consumption for landing (lunar slide lander, LSL); the other (drop delivery method, DDM) avoids release of propellant gases at the lunar surface. The LSL is of particular promise and importance. Its analysis and development introduces a new field of cosmic dynamics—harenodynamics, the science and technology of interaction of surfaces with dust and sand at near-orbital speeds down to low velocities. Although the data base is small so far and needs to be enlarged, analyses of the LSL so far indicate promise as to feasibility. Its realization will revolutionize present conventional concepts of lunar development. The DDM offers cost-effective alternatives to conventional lunar landing by retrothrust, but on a more selective basis, because propellant-savings are secondary to avoiding gas releases into the lunar high-vacuum environment. It was found that stationary energy absorption systems (EAS) are required, because vehicle-attached absorption systems are entirely inadequate. This requires large structures which can be built on the lunar surface only after a somewhat higher degree of industrial capability has been established. However, they can be built entirely of lunar materials. Altogether, the LSL is the more significant of the two both in terms of economy and of operational scope.  相似文献   
6.
This first of several study papers, based on a fundamental paper presented in 1972, provides an independent conceptual analysis and evaluation of the lunar environment as industrial base and habitat. A selenosphere system strategy is outlined. The underlying concept is that of one or several lunar industrial zones for resource extraction and on-surface processing, integrated with a circumlunar zero-g processing capability, serving markets in geolunar space. A classification of lunar elements by utilization category is presented. Lunar oxygen is a prime candidate for being an initial economic “drawing card”, because of its value for fast transportation in geolunar space, requiring significantly fewer ships for equal transfer capability per unit time than electric transports which, however, have value, especially between geosynchronous and lunar orbit. The reduced development difficulties of controlled fusion outside the atmosphere and its advantages for extracting oxygen and other elements in quantity are summarized. Examples of lunar cycle management as fundamental exoindustrial requirement for economic resource enhancement are presented. The principal initial socio-economic value of lunar industry lies in the use of lunar resources for exoindustrial products and operations designed to accelerate, intensify and diversify Earth-related benefits. In the longer run, lunar settlements are a highly suitable proving ground for studying and testing the complex matrix of technological, biological, cultural, social and psychological aspects that must be understood and manageable before large settlements beyond Earth can have a realistic basis for viability. The lunar environment is more suitable for experimentation and comparatively more “forgiving” in case of failures than is orbital space.  相似文献   
7.
In the context of investigations to maximize the operational utilization of local resources on other worlds, a concept for using fine lunar sand as cooling medium for the rejection of waste heat is developed. Sand at cryogenic temperature is admixed to the working fluid containing the waste heat. Gas and sand form a mix of the desired and temperature of the working fluid. Subsequently, the sand is removed and intensely radiation-cooled, utilizing its very large surfacevolume ratio. Thereafter it is recycled. It is shown that, compared to heat rejection by radiator, harenodynamic cooling offers superior efficiency, greater compactness and lower cost, improving the economics of nuclear power plants and of industrial expansion on the Moon in general.  相似文献   
8.
Space light: space industrial enhancement of the solar option   总被引:1,自引:0,他引:1  
The solar option can be enhanced significantly by space light technology. Reflectors in suitable orbits beam to Earth measured amounts of sunlight, the most versatile and bio-compatible energy source. The multitude of space light functions ranges from night illumination of rural and urban areas (by Lunetta systems) to photosynthetic production enhancement for the growth of food and of biomass for conversion to chemical fuels, local agricultural irradiation for crop drying and weather stabilization and to electric power generation by irradiating suitable photovoltaic or thermal ground receivers at night or by adding to the natural solar energy input during daytime (Soletta systems).

The Lunetta and Soletta concepts, developed by the author during the past ten years, building on the foundations laid by the great space pioneer Prof. H. Oberth (1928), are reviewed, along with their socio-economic merits. An assessment of terrestrial alternatives shows that many useful functions have no practical alternative, the major exception being electric power generation. Three systems are selected, bracketing the broad versatility of space light—Lunetta, Powersoletta and a large Biosoletta for large-scale seafood production in Antarctic and Artic waters. The systems, and several maintenance and supply requirements are described, sized and analyzed, along with suitable orbit selection for different applications. Models are developed for rural and urban area lighting, power generation at selected sites around the globe with photovoltaic and thermal ground stations and for the large-scale production of seafood at high southern and northern latitudes with ample nutrient upwell, but insufficient annual supply of solar energy. The economics of these systems is analyzed.  相似文献   

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