scholarly journals Research Reactors in the United States

Nature ◽  
1956 ◽  
Vol 177 (4509) ◽  
pp. 593-594
Author(s):  
J. D. COCKCROFT
Author(s):  
Jas S. Devgun

The experience related to decommissioning of nuclear facilities in the United States is very substantial and covers power reactors, research reactors, and many facilities in the Department of Energy complex. The focus of this paper however is on the commercial power plants. With 104 operating reactors, the U.S. fleet of civilian reactors is still the largest in the world. Nuclear power industry in the United States has undergone a dramatic upturn after decades of stalemate. One effect of this nuclear renaissance has been that the plans have changed for several reactors that were initially destined for decommissioning. Instead, the focus now is on relicensing of the reactors and on power uprates. In fact, after the peak period between 1987 and 1998, no additional power reactors have been shutdown. On the contrary, power uprates in the past twenty years have added a cumulative capacity equivalent to five new reactors. Almost all the operating reactors plan to have license extensions, thus postponing the eventual decommissioning. Nevertheless, in addition to the 9 reactors where licenses have been terminated following decommissioning, 12 power and early demonstration reactors and 14 test & research reactors are permanently shutdown and are in decommissioning phase. Substantial experience and lessons learned are available from the U.S. projects that are of value to the international decommissioning projects, especially where such projects are in early stages. These lessons cover a wide array of areas from decommissioning plans, technology applications, large component removal, regulatory and public interface, decommissioning funding and costs, clean up criteria, surveys of the decommissioned site, and license termination. Additionally, because of the unavailability of a national spent fuel disposition facility, most decommissioning sites are constructing above ground interim storage facilities for the spent nuclear fuel. The U.S. nuclear power projects are also gearing up for the design and licensing of new reactors. Lessons from the past are useful in the development of such designs so that along with the other factors, the designs are optimized for eventual decommissioning as well. This paper provides an overview of the past reactor decommissioning, lessons learned from the past experience, and status of the current decommissioning activities and issues. It also presents some long term projections for the future of decommissioning in the United States.


Author(s):  
Haiyang Wang ◽  
Chenxiu Song ◽  
Quanyuan Gao

There are 19 in-service civil research reactors in China nowadays, which are quite diverse on reactor type, usage, power levels, operation modes and safety features [1]. The common practice in nuclear energy advanced countries is to do safety classification and classified management of research reactors. In recent years, China has gradually refined and improved the related work. This paper summarizes the existing research reactor graded approach and safety management requirements included in certain regulations, guidelines and technical documents of IAEA, the United States, Japan and China, and specific practice and experience on operational level as well. And then the classification principles, classification elements, classification methods, safety management requirements and other aspects of the countries or government organizations mentioned above are compared from the view of research reactor safety classification. It comes to the conclusion: As far as China’s research reactor graded approach and safety management requirements are concerned, more work are needed. The relevant provisions of research reactor graded approach of IAEA are comprehensive, and have good reference value for China’s legislation system, but the classification method operability is not strong enough, and there are no detailed management and technical guides as the supplement to the graded approach. The relevant provisions of the research reactor graded approach of the United States and Japan are not systemic enough, but the classification methods are clear and operable, which are referable for China’s relevant practice on research reactor safety classification. After the Fukushima nuclear power plant accident, the classified management of the research reactors has achieved quite good results in comprehensive safety inspection of China’s civil research reactors. Finally, some suggestions in respect of the establishment and improvement of China’s research reactor safety classification guidelines and documents, standardization the use of graded approach, and application in the review and supervision of research reactor in China are put forward.


Author(s):  
A. Hakam ◽  
J.T. Gau ◽  
M.L. Grove ◽  
B.A. Evans ◽  
M. Shuman ◽  
...  

Prostate adenocarcinoma is the most common malignant tumor of men in the United States and is the third leading cause of death in men. Despite attempts at early detection, there will be 244,000 new cases and 44,000 deaths from the disease in the United States in 1995. Therapeutic progress against this disease is hindered by an incomplete understanding of prostate epithelial cell biology, the availability of human tissues for in vitro experimentation, slow dissemination of information between prostate cancer research teams and the increasing pressure to “ stretch” research dollars at the same time staff reductions are occurring.To meet these challenges, we have used the correlative microscopy (CM) and client/server (C/S) computing to increase productivity while decreasing costs. Critical elements of our program are as follows:1) Establishing the Western Pennsylvania Genitourinary (GU) Tissue Bank which includes >100 prostates from patients with prostate adenocarcinoma as well as >20 normal prostates from transplant organ donors.


Author(s):  
Vinod K. Berry ◽  
Xiao Zhang

In recent years it became apparent that we needed to improve productivity and efficiency in the Microscopy Laboratories in GE Plastics. It was realized that digital image acquisition, archiving, processing, analysis, and transmission over a network would be the best way to achieve this goal. Also, the capabilities of quantitative image analysis, image transmission etc. available with this approach would help us to increase our efficiency. Although the advantages of digital image acquisition, processing, archiving, etc. have been described and are being practiced in many SEM, laboratories, they have not been generally applied in microscopy laboratories (TEM, Optical, SEM and others) and impact on increased productivity has not been yet exploited as well.In order to attain our objective we have acquired a SEMICAPS imaging workstation for each of the GE Plastic sites in the United States. We have integrated the workstation with the microscopes and their peripherals as shown in Figure 1.


2001 ◽  
Vol 15 (01) ◽  
pp. 53-87 ◽  
Author(s):  
Andrew Rehfeld

Every ten years, the United States “constructs” itself politically. On a decennial basis, U.S. Congressional districts are quite literally drawn, physically constructing political representation in the House of Representatives on the basis of where one lives. Why does the United States do it this way? What justifies domicile as the sole criteria of constituency construction? These are the questions raised in this article. Contrary to many contemporary understandings of representation at the founding, I argue that there were no principled reasons for using domicile as the method of organizing for political representation. Even in 1787, the Congressional district was expected to be far too large to map onto existing communities of interest. Instead, territory should be understood as forming a habit of mind for the founders, even while it was necessary to achieve other democratic aims of representative government.


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