Disposal of Nuclear Wastes: At an increased but still modest cost, more options can be explored and the outlook can be improved

For the present and the foreseeable future the following options appear to be either usable or worth further exploration: mausolea; disposal in mines of various sorts, and perhaps in ice; in situ melt; and further chemical separations. The options are interdependent. It is too early to assess disposal in space, and disposal in the oceans remains unsafe for lack of adequate knowledge. Table 3 is a summary of the main ideas for which we have worked out (sometimes uncertain) costs. For the short term, ultimate disposal in deep mines is the best-developed plan. However, the related concept of in situ melt has significant advantages and should be realistically appraised. Further chemical separation with subsequent recycling of the actinides in a LMFBR should be investigated and implemented, for it would be universally beneficial; on the other hand, additional removal of strontium and cesium does not seem attractive. Thus, for the near future we make the following recommendations: 1) Provide temporary storage facilities to ensure that the projected commercial high-level wastes do not become a public hazard. The AEC adopts this view, and has stated an intention to construct such facilities. But because of the capriciousness of man and nature, a workable ultimate disposal scheme must be developed soon. 2) Fund other ultimate disposal schemes at the same rate as the salt mine project-say $1 million a year or more-to sharpen the technological issues, so that a decision can be reached in the next few years. The schemes should include (i) in situ melt, and the variation with a central repository; (ii) burial in mines other than salt mines (including Antarctic rocks and permanent ice); (iii) further chemical separation of actinides and recycling actinides in a LMFBR. 3) Maintain liaison with the developing space shuttle technology to insure that no opportunity is lost. The AEC has a commitment to hold safety foremost in its waste management program, but budget considerations and management priorities have downgraded the program. Past funding levels and management emphasis have yet to produce, after a decade and a half, one operational long-term storage facility-a sign of both commendable caution and inadequate work. If nuclear power is to resolve our energy needs in the coming decades, its benefits should not be delayed for lack of a viable management program for high-level wastes.     

David on Neutrality of NAS, PSAC

The two most significant conduits through which scientific advice is channeled to government are the National Academy of Sciences (NAS)and the President's Science Advisory Committee (PSAC). The neutrality of these two bodies has on occasion been called into question by their critics, but seldom from within. In a philosophic but candid interview published in a recent issue of Mosaic, house organ of the National Science Foundation, Edward E. David, the President's science adviser and chairman of PSAC, suggests that the Academy and PSAC may behindered by their government links from offering scientific advice in an unbiased and credible way.     

Science in europe/the antinuclear movement takes hold

Five months after the announcement of President Carter's nonproliferation policy, the common wisdom in this country is that Europe has hardly wavered in its rush toward nuclear power. The cry that "Europe will do what it wants whether the United States builds a breeder or not" is often heard from American nuclear interests, with apparent justification as the State Department has shown little visible progress in negotiating new agreements and some signs of retreating from its original goals. But popular protest against nuclear power has reached a pitch in Europe that would be barely imaginable today in this country, and the political strength of the antinuclear forces has become formidable, not only in Sweden where nuclear power was a pivotal issue last year, but across the continent. West Germany's research minister recently predicted that that country's two ruling coalition parties will vote for a complete moratorium on nuclear construction when they meet this fall, and some observers predict that any moratorium contingent on creation of a waste disposal site could last up to 12 years. Beyond public opposition, the plutonium breeder is running into trouble in Germany for many of the same reasons it has in the United States; program delays, safety concerns, and cost overruns threaten to undermine the claim that it can one day become an economically competitive energy source. Nuclear opposition is far from being a single-issue movement in Europe, as groups of many political persuasions embrace it for their own reasons. But as the following report by Nigel Hawkes details, the Carter administration policy is not the only thing holding back nuclear power in Europe.-W.D.M.     

农户接受农业生态补偿方式的偏好及影响因素——基于海南省16个自然村的调查

农户对农业生态补偿方式的认同度,对补偿实施效果及补偿政策制度的持续性有直接影响。以海南省16个自然村为案例的调查结果显示:技术、政策、实物、现金、项目等多要素结合的补偿是农户接受农业生态补偿方式的主要偏好。以偏好该方式的农户为对象,最优尺度回归方法分析表明:家庭规模、家庭收入来源、农业生态系统及其功能认知度等变量对农户该选择倾向有显著正向影响;而年龄、对农业生态补偿的认知度则有显著负向影响。从获取综合化补偿绩效的角度出发,加强政策、技术、知识、项目等的投入运用,利于实现农业生态补偿由单一"输血型"向"造血型"转变。此外,纠正农户对农业生态补偿认知偏差问题也值得关注。     

The safety goals of the U.S. Nuclear Regulatory Commission

In August 1986, after 6 years of effort, the U.S. Nuclear Regulatory Commission adopted a Policy Statement on safety goals for nuclear power reactors. The commission's qualitative goals state that individual members of the public should be provided a level of protection from the consequences of nuclear power plant operation such that they bear no significant additional risk to life and health, and societal risks to life and health from nuclear power should be comparable to or less than the risks of generating electricity by viable competing technologies and should not be a significant addition to other societal risks. The commission's safety goal Policy Statement also includes quantitative design objectives.     

农业龙头企业绩效影响因素的实证分析——基于董事长和总经理合职与分离的角度

利用国家级农业产业化龙头企业数据,对董事长和总经理合职与分离对农业龙头企业绩效的影响进行分析。研究结果显示:资本投入和劳动力投入对农业龙头企业绩效的贡献较大,订单量和合同带动农户数对农业龙头企业绩效起到正向作用,然而,董事长和总经理合职对农业龙头企业绩效的作用并不明显。两职合并使得西部地区农业龙头企业绩效上升19.17%,其中民营企业和其他企业绩效分别上升15.03%和47.07%;而两职合并对于东部地区农业龙头企业绩效的影响产生负向作用,其中使得其他企业绩效下降31.62%。根据本研究结果,建议伴随着农业龙头企业的规模的扩大,董事长和总经理两职应该分离。     

Radioactive wastes: a comparison of u.s. Military and civilian inventories

Contrary to widespread belief, the accumulated inventory of fission products generated by the still small U.S. civilian nuclear power industry may already be comparable to that generated in the past by U.S. military nuclear programs. Although the volumes of the military wastes are very large, they are on the average almost 100 times more dilute than projected commercial high-level wastes.     

Electromagnetic Separation of Isotopes at Oak Ridge: An informal account of history, techniques, and accomplishments

In 1960 I attended a European conference on isotope separation, after which I visited the Niels Bohr Institute in Copenhagen. A staff member there ventured the opinion that the separation of isotopes will be first on the list of important contributions to the peaceful uses of the atom when the Atomic Energy Commission's memoirs are written in the year 2000. In 1968 the AEC Division of Research contracted with the National Research Council of the National Academy of Sciences to conduct a review of the AEC program for the separation of stable isotopes by electromagnetic and thermal diffusion methods. This ad hoc panel comprised seven scientists from the fields of chemistry, classical physics, geochemistry, geophysics, medicine, and physics. In their final report on national uses and needs for separated stable isotopes (9), they referred to the store of separated isotopes as a "real national asset that attains increasing value as science and technology develop" and recommended "continuation of the program as a national resource of great value to the United States." Later, in a discussion of this report with A. M. Weinberg, J. Koch, himself a pioneer in electromagnetic isotope separation and member of the Danish Atomic Energy Program, said he would correct the statement that the Oak Ridge electromagnetic facility is a "national asset" to read "international asset." From my narrow viewpoint after an extended and complete engrossment with this program for so many years, it is gratifying to learn that such men as those mentioned above share my belief that the work has indeed been worthwhile.     

News of Science

On page 925 of the 9 Nov. issue of Science we stated that "Nineteen members of the Atomic Energy Commission research project at the University of Rochester Medical Center" endorsed a statement criticizing the President's recent defense of nuclear weapons tests. Actually, only five of the 19 members of the university staff who signed the statement were associated with the AEC project. These five constituted about 10 percent of the project's scientific staff.     

＂主导产业、支柱产业＂在农业产业化中的误用研究

结合农业产业化的特点和区域经济学的相关理论,论述了＂主导产业、支柱产业＂在农业产业化中的误用。结果表明,＂主导产业、支柱产业＂属于经济学专业术语,概念上有比较明确的界定,在产业定位与选择上也有具体的指标,因此,在农业产业化概念、组织形式、评价指标中的使用必须规范谨慎。     

Nuclear eclectic power

The uranium and thorium resources, the technology, and the social impacts all seem to presage an even sharper increase in nuclear power for electric generation than had hitherto been predicted. There are more future consequences. The "hydrogen economy." Nuclear power plants operate best at constant power and full load. Thus, a largely nuclear electric economy has the problem of utilizing substantial off-peak capacity; the additional energy generation can typically be half the normal daily demand. Thus, the option of generating hydrogen as a nonpolluting fuel receives two boosts: excess nuclear capacity to produce it, plus much higher future costs for oil and natural gas. However, the so-called "hydrogen economy" must await the excess capacity, which will not occur until the end of the century. Nonelectric uses. By analyses similar to those performed here, raw nuclear heat can be shown to be cheaper than heat from many other fuel sources, especially nonpolluting ones. This will be particularly true as domestic natural gas supplies become more scarce. Nuclear heat becomes attractive for industrial purposes, and even for urban district heating, provided (i) the temperature is high enough (this is no problem for district heating, but could be for industry; the HTGR's and breeders, with 600 degrees C or more available, have the advantage); (ii) there is a market for large quantities (a heat rate of 3800 Mw thermal, the reactor size permitted today, will heat Boston, with some to spare); and (iii) the social costs become more definitely resolved in favor of nuclear power. Capital requirements. Nuclear-electric installations are very capital-intensive. One trillion dollars for the plants, backup industry, and so forth is only 2 percent of the total gross national product (GNP) between 1974 and 2000, at a growth rate of 4 percent per year. But capital accumulation tends to run at about 10 percent of the GNP, so the nuclear requirements make a sizable perturbation. Also increasing the electric share of energy provision means increasing electric power utilization, which has a high technological content and demands yet more capital. Thus, provision of capital is a major problem ahead, especially for electric utilities. The need for people. The supply of available trained technologists, environmental engineers, and so on, especially in the architect-engineer profession, is insufficient for the task ahead, especially since the same categories of people will be in demand to build up a synthetic fuels industry and do other new things. Beyond these specific items and beyond the technological discussion, one can feel deeper currents running in this debate. Issues that started out seeming technological ended up being mainly societal: prevention of clandestine use, either by vigilance or by public spirit; a determination to maintain quality and to safeguard wastes that transcends narrow interests; a perception of social benefits and damage much more holistic than before; the need to manage programs more openly and better than before. Questions and doubts become more acute, answers and methods less sure. Here is a final question. We have never before been given a virtually infinite resource of something we craved. So far, increasingly large amounts of energy have been used to turn resources into junk, from which activity we derive ephemeral benefit and pleasure; the track record is not too good. What will we do now?     

Energy needs versus environmental pollution: a reconciliation?

In this article I have presented, for discussion, a proposed system for energy generation by which the principal sources of environmental pollution by power plants could be eliminated. For stationary power plants the concept appears feasible technically and, according to my " horseback estimates," perhaps economically as well, depending upon the economic value of the by-products of sulfur, CO(2), water, and possibly nitrogen, and upon the price we are willing to pay for a clean environment .Thus, a more thorough engineering and economic analysis to explore these and other factors in greater depth seems warranted. In the case of turbine-driven vehicles, the technical and economic feasibility of widespread distribution and handling of the fuel constitutes a serious question, but one which deserves equally serious consideration before the possibility is discounted. The reports of the cited study panels notwithstanding, the technology required for the proposed system exists today, with one exception. This exception (which is not essential for trial of the system but will be required for its complete fruition) is the development of a nuclear reactor for the prime purpose of delivering process heat for the steam reforming of natural gas and, ultimately, for gas production from coal in a continuous process, such as those discussed by Pieroni et al. (16). Today's intermittent processes of coking and gas production are both archaic and themselves large sources of atmospheric pollution, and a development program aimed at advancing the technology of the coal industry in this regard would seem long overdue. The report of the PSAC Environmental Pollution Panel recommended "demonstration of the feasibility and economy of new developments for abating or controlling pollution through their use at Federal installations" and suggested the coalburning TVA power plants as a likely place for such demonstration. This suggestion is doubly appropriate since the TVA is in a region of subnormal " atmospheric ventilation" (8). By design these plants are adjacent to the AEC's Oak Ridge National Laboratory, and such a location would seem ideal for an experiment on the wedding of nuclear and fossil sources of energy. In comments on a preliminary draft of this article, proponents of "conventional " nuclear power pointed out that such power is hard to beat on the basis of cost, and that dissipation of heat to the air by way of cooling towers can also be accomplished in conventional plants (17). These observations are individually correct but not compatible: the low power costs cited are for very large plants [of the order of 1000 mega-watts lectrical) and larger], and the costs of cooling towers and associated equipment needed to dissipate such large amounts of heat [of the order of 2000 megawatts (thermal)] to air from a closed cycle would offset the power cost advantage of the large plant. In regard to the proposed use of nuclear process heat, Weinberg (20) has expressed doubt that much advantage can be derived from this approach because the temperatures involved are too high for low-cost reactors, and heat transfer from surfaces could involve materials problems. In the case of gas production, this is indeed an anticipated problem-not a technologically insuperable one, but a problem of reducing the cost of the materials required (16). Indeed, Weinberg himself has mentioned this possible use of nuclear heat in a recent publication discussing the steam reforming of coal to liquid fuel(21). Also, an improved process for synthesizing methane from lignitec has recently been reported (22). Since the earlier studies date back a decade, a new look at the problems and costs involved relative to the benefits to be derived (not the least of which could be new vigor for the coal industry) would seem to be in order. In the case of steam reforming of natural gas, the temperature level (about 1500 degrees F) is such that the technology is available today, and a process-heat-reactor design study could be initiated without awaiting further developments.     

University Isotope Separator at Oak Ridge: The UNISOR Consortium

The UNISOR cooperative project, envisioned more than 3 years ago, is now successfully working. Research problems that involve a full range of experiments on nuclei far from beta stability are being investigated jointly by groups of scientists from several institutions. Some of the first work reported (16) included the identification, half-lives, and decay schemes of three new isotopes, (186)T1, (188)T1, and (116)I; the first or new decay schemes of (189)T1, (190)T1, (117)Xe, and (117)I; and the results of the perturbed gamma-gamma directional correlation work in (126)Xe. UNISOR is already stimulating international interest. A report (1) on the new research being planned with an isotope separator on-line to ORIC was presented at a Soviet Academy of Sciences meeting on nuclear structure in 1971. At an international nuclear physics conference in Munich in August 1973, Academician G. N. Flerov, director of the heavy-ion laboratory in Dubna, said the UNISOR project had inspired his laboratory to secure funds for a new, much improved isotope separator which is now installed on-line to their heavy-ion cyclotron to be used for detailed studies of nuclei far from stability. The UNISOR model for research has inspired a second such project, the Atomic Physics Consortium at Oak Ridge (APCOR). After an exploratory conference at Oak Ridge, scientists from ten institutions met in November 1973 to form an organizing committee for APCOR. As with UNISOR, the universities and the AEC will each provide a significant portion of the capital and operating costs. Heavy ions have opened up much new research in atomic physics, but such accelerator-based research represents a real "shift from traditional approaches concerning how, where, and on what time scale atomic physics experiments should be done" (17).     

Erratum

In R. Jeffrey Smith's News and Comment article "Antisatellite weapon sets dangerous course" (14 Oct., p. 140), a remark on page 141 (column 3) by Richard Garwin about the usefulness of rockets, balloons, and aircraft to supplant U.S. photoreconnaissance and meterological satellites was inadvertently attributed to Robert Buchheim. And a characterization on page 141 (column 2) of the Soviet antisatellite weapon, or ASAT, was actually made by General Lewis Allen, the former Air Force chief of staff, not by General David Jones, the former chairman of the Joint Chiefs of Staff. Finally, a footnote on page 142 should have identified the Patriot as an air-to-air missile, not an air-to-ground missile.     

Melmon resigns Stanford chairmanship

The chairman of Stanford Medical School's department of medicine, Kenneth Melmon, has resigned his administrative position after receiving a letter of censure from Stanford president Donald Kennedy. A university ethics committee had found Melmon guilty of negligent scholarship after it was discovered that a textbook chapter authored by him contained unattributed material from a book he had earlier helped edit. Melmon maintained that permission to use the material and its proper attribution had been handled by his editor, but this later proved not to be the case. Stanford plans no further action in the matter, and Melmon will retain his professorship.     

Bioethics. Financial conflicts get more scrutiny in clinical trials

At a national conference on clinical research last week, the incoming head of the federal government's new Office for Human Research Protections, Greg Koski, surprised his audience by suggesting that some conflicts should be avoided. His support for the idea that scientists should have no financial ties to companies whose products they are testing hints at an upcoming shift in government rules that govern the relationship between scientists and the pharmaceutical industry. But most of the discussion at the conference revolved around questions of how to "manage" conflicts rather than do away with them.     

基于VAR模型的中国马铃薯产量波动影响因素分析

为明确马铃薯产量波动影响因素及其作用机制,保持我国马铃薯产业平稳健康发展,本研究运用VAR模型对1982-2018年影响我国马铃薯产量波动的因素进行分析,揭示我国马铃薯生产影响机制,最后对合理引导我国马铃薯生产平稳发展提出相应对策建议。结果显示:(1)自然因素对产量波动多为负向影响,经济、科技和政策以正向影响为主;(2)自然、科技和市场因素对马铃薯产量波动的影响较大,科技进步与政策影响较为长远。研究认为应从制定适当生产引导政策、提升马铃薯生产效率水平、增强应对自然因素冲击能力、拓展多种马铃薯产品消费途径四个方面采取对策措施,稳定马铃薯生产。     

Can science survive in the modern age?

A recent newspaper account of the 1970 annual meeting of the AAAS was headlined, "Science's Blank Check Bounces." I am not, however, advocating that giving a "blank check" to science will solve all our problems. The discussion of science policy in the last three decades has too often confused necessary with sufficient conditions. A strong basic science is a necessary condition for a strong economy, a livable environment, and a tolerable society. But it is by no means a sufficient condition. That a vital science is an indispensable tool of human welfare in the present stage of evolution of man on the planet does not mean that it is the only tool or that it cannot also produce the opposite. Indeed, there seems almost to be a complementarity between the power for good and the power for evil inherent in science. Nuclear energy poses the possibility of nuclear holocaust, but is indispensable to a continuing supply of energy after fossil fuels run out. The computer threatens us with "big brother," but seems indispensable to the rational management of our complex social structures. Molecular genetics could be used for frightful purposes, but opens up the prospect of the final conquest of human disease and food supply. Drugs which control human behavior have opened up frightful possibilities for abuse and self-destruction, but they also offer the hope of conquest of mental illness. What I have referred to are really technologies, not science, but science is needed to use them wisely, although it will not guarantee their wise use. Although science cannot ask for a blank check, there is a part of it which must have the autonomy to "do its own thing"if it is to continue to serve society. How much of science should have this autonomy, and what sort of accountability should be required of it will be matters of continuing debate. Some accountability outside the scientific system itself is essential, as in any other human activity, but the degree of external accountability which is necessary will depend also on the success with which science maintains its own system of internal accountability, guaranteeing the intellectual excellence and integrity of its results. Although I do not believe scientists can be held accountable for the uses which society makes of the knowledge they produce, they do have an obligation to make clear the implications of this knowledge insofar as it is within their special intellectual competence to do so. However, I believe that the highest allegiance of science must continue to be to truth as defined by the validation procedures of the scientific process itself, and that the distortion of scientific results or the selective use of evidence for political purposes, no matter how worthy, is unforgivable insofar as it is presented cloaked by the authority and imputed objectivity of science. That science should have a measure of autonomy does not mean it cannot also respond to new social priorities. As in the past, new social missions can open up exciting new scientific questions, as fundamental as any generated by the internal workings of science. However, what is important is that no matter how much the broad strategy of science might be influenced by social priorities, the tactics should be largely governed by scientific criteria. Furthermore, it is essential that some science be supported and cultivated for its own sake alone. Here the primary criterion must be excellence as judged scientifically, that is, by internal standards. The fraction of the total technical effort that is supported in this way should have some degree of constancy over the long term. You are no doubt wondering what is the answer to the question posed by the title of this article. I cannot give a definite answer one way or the other. The threats to the integrity of science, both from within and from without, are probably greater than at any time in the past, because science is much more a part of the total social and political process, no longer the semihobby of a few dedicated and somewhat eccentric individuals. But I am an optimist. I do not think that the scientific enterprise is going down the drain. It will change, as science has always changed. It will respond to new social priorities, but, like an organism responding to disease, it will develop antibodies which will fight and finally contain excessive control by external criteria, and in fact will transform these external pressures into new opportunities and new fundamental fields of inquiry. But I could be wrong!     

从品牌的角度分析中宁枸杞市场竞争力

对中宁枸杞品牌的形成及其市场现状进行了深入分析,并在此基础上提出了如何提高中宁枸杞竞争力的对策。     

Erratum

In the article "Nuclear risks: Still uncertain" (News and Comment, 18 May, p. 714), in the fourth paragraph, the sentence, "If one assumes that 40 gigawatts are produced a year, as was the case in 1975. . ., then the nuclear industry is causing two cancer deaths a year," should have read, "20 cancer deaths a year."