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Sample records for arkansas power-light-1 reactor

  1. BEACON/MOD2A analysis of the Arkansas-1 reactor cavity during a hypothetical hot leg break

    International Nuclear Information System (INIS)

    As part of the evaluation of the new MOD2A version of the BEACON code, the Arkansas-1 reactor cavity was modeled during a hypothetical loss-of-coolant accident. Results of the BEACON analysis were compared with results obtained previously with the COMPARE containment code. Studies were also made investigating some of the BEACON interphasic, timestep control, and wall heat transfer options to assure that these models were working properly and to observe their effects on the results. Descriptions of the Arkansas-1 reactor cavity, initial assumptions during the hypothetical LOCA, and methods of modeling with BEACON are presented. Some of the problems encountered in accurately modeling the penetrations surrounding the hot and cold leg pipes are also discussed

  2. Slamming Arkansas Schools!

    Science.gov (United States)

    Scott, W. Clayton

    2010-01-01

    In this article, the author, a poet and teaching artist, shares how he successfully brought slam poetry to College Hill Middle School in Texarkana, Arkansas. In 2001 he discovered slam poetry--a poetry-reading format in which poets compete in dramatic readings of their works--and went to Slam Nationals in Seattle on the Arkansas slam team. He…

  3. Arkansas' Disappearing Tax Base.

    Science.gov (United States)

    Schoppmeyer, Martin; Venters, Tommy

    State legislation that has contributed to the reduction of Arkansas' tax base is described in this paper. Amendment 59, adopted in 1980, has reduced the state tax base by millions of dollars. At the end of 1992, the majority of school districts have equalized their real, personal, and carrier and utility property. Act 34, the current foundation…

  4. Arkansas River Water Needs Assessment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is on the legal elements, hydrologic analysis, objectives, and water levels related to the Arkansas River and the management of it.

  5. Marshallese COFA Migrants in Arkansas.

    Science.gov (United States)

    McElfish, Pearl Anna

    2016-05-01

    Arkansas is home to one of the largest populations of Marshallese in the world. Marshallese communities suffer from a disproportionate incidence of chronic diseases, including obesity, cardiovascular disease, diabetes, and infectious diseases, such as Hansen's disease (leprosy), tuberculosis, and types of hepatitis. There are a number of structural, legal, economic, and social issues that must be addressed in order to reduce health disparities and increase access to health care for Marshallese living in Arkansas. PMID:27263176

  6. 33 CFR 117.121 - Arkansas River

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Arkansas River 117.121 Section 117.121 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.121 Arkansas River The draw of...

  7. Abortion applicants in Arkansas.

    Science.gov (United States)

    Henker, F O

    1973-03-01

    The article reports upon the characteristics of 300 abortion applicants in Arkansas manifesting significant stress from unwanted pregnancy between May 1, 1970 and June 30, 1971. The sample is limited by the fact that all of these women had been willing to seek medical aid. Patients ranged from ages 13-47, 131 of them ages 17-21. 35% had had some college education; another 29% were high school graduates. 50.6%, 20.6%, and 27.3% were single, divorced, and married, respectively. 59.6% of the patients were primiparas. 18.3%, 9.6%, and 12.3% were classified as being neurotic, having psychophysiologic tendencies (gastrointestinal problems, obesity, chronic headaches), and having sociopathic features (passive-aggressive, frankly rebellious, delinquent, antisocial, alcoholic), respectively. 12 women had noticeable schizoid features; 4 women had mildly active schizophrenia. Fathers of the women were usually blue-collar workers (55.3%) or white-collar workers (24.6%). The most frequent ordinal sibling position among the women was oldest child (38%). Parental instability (1 or both parents lost through death, divorce, father usually away working, chronic alcoholism, etc.) was reported by 39.6% of the patients. Patients' attitudes toward the unwanted pregnancy included dislike of inexpediency of the situation (82.6%), self-depreciation (55.6%), and aversion (28.6%). Precipitated psychiatric disorders were for the greatest part mild. Manifesting symptoms included depression (66.7%), anxiety (21%), and mixed anxiety and depression (12.2%). Suicidal threats and gestures were made by 22 and 8 patients, respectively. In summary, the study reveals a group of predominantly Caucasian women from unstable, middle-class urban families who were going through an adjustment reaction to adolescence or adult life.

  8. Arkansas: Its Land and People, Vol. 1.

    Science.gov (United States)

    Foti, Tom

    This bicentennial volume offers a blend of Arkansas history, ecology, and literature. Its purpose is to show the relationship between Arkansas' people and their land. It contains a discussion of the Natural Divisions concept, the geological development of the state, and descriptions by early pioneers. The volume is not intended to be a complete…

  9. Arkansas State University Beebe Branch Faculty Handbook.

    Science.gov (United States)

    Arkansas State Univ., Beebe.

    Arkansas State University Beebe Branch provides a liberal arts oriented program for traditional and nontraditional students. Its faculty handbook contains institutional goals, description of responsibilities of administrative officers and faculty committees, faculty employment policies, and administrative and instructional policies. The…

  10. Arkansas' Children: How Well Are They Doing? Arkansas Kids Count Data Book 1996.

    Science.gov (United States)

    Dahlstrom, Sherryl M.; High, Rhonda L.

    This Kids Count data book is the fourth to examine the well-being of Arkansas' children and notes trends from 1990 to 1995. The report's introductory sections include discussions of the potential impact of welfare reform on Arkansas' children, and present figures detailing the number of children affected by particular risk factors each week. The…

  11. Arkansas' Junior Executive Training Curriculum Guide.

    Science.gov (United States)

    Clayton, Dean; And Others

    This curriculum guide is designed to help teachers conduct courses on small business management and entrepreneurship to high school seniors in Arkansas. The program focuses upon the managerial process, examining the functions of planning, organization, staffing, directing, and controlling as related to the activities and responsibilities of the…

  12. 78 FR 9448 - Arkansas Disaster #AR-00061

    Science.gov (United States)

    2013-02-08

    ... ADMINISTRATION Arkansas Disaster AR-00061 AGENCY: U.S. Small Business Administration. ACTION: Notice SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the... Disaster Assistance, U.S. Small Business Administration, 409 3rd Street SW., Suite 6050, Washington,...

  13. 27 CFR 9.112 - Arkansas Mountain.

    Science.gov (United States)

    2010-04-01

    ... Jean Creek. (vi) Then generally northeastward and eastward along Petit Jean Creek until it becomes the Petit Jean River (on the Russellville map). (vii) Then generally eastward along the Petit Jean River, flowing through Blue Mountain Lake, until the Petit Jean River joins the Arkansas River. (viii)...

  14. Rickettsiae in Gulf Coast Ticks, Arkansas, USA

    OpenAIRE

    Trout, Rebecca; Steelman, C Dayton; Szalanski, Allen L.; Williamson, Phillip C

    2010-01-01

    To determine the cause of spotted fever cases in the southern United States, we screened Gulf Coast ticks (Amblyomma maculatum) collected in Arkansas for rickettsiae. Of the screened ticks, 30% had PCR amplicons consistent with Rickettsia parkeri or Candidatus Rickettsia amblyommii.

  15. Identifying sites for elk restoration in Arkansas

    Science.gov (United States)

    Telesco, R.L.; Van Manen, F.T.; Clark, J.D.; Cartwright, Michael E.

    2007-01-01

    We used spatial data to identify potential areas for elk (Cervus elaphus) restoration in Arkansas. To assess habitat, we used locations of 239 elk groups collected from helicopter surveys in the Buffalo National River area of northwestern Arkansas, USA, from 1992 to 2002. We calculated the Mahalanobis distance (D2) statistic based on the relationship between those elk-group locations and a suite of 9 landscape variables to evaluate winter habitat in Arkansas. We tested model performance in the Buffalo National River area by comparing the D2 values of pixels representing areas with and without elk pellets along 19 fixed-width transects surveyed in March 2002. Pixels with elk scat had lower D2 values than pixels in which we found no pellets (logistic regression: Wald χ2 = 24.37, P cover, gently sloping ridge tops and valleys, low human population density, and low road densities. To assess the potential for elk–human conflicts in Arkansas, we used the analytical hierarchy process to rank the importance of 8 criteria based on expert opinion from biologists involved in elk management. The biologists ranked availability of forage on public lands as having the strongest influence on the potential for elk–human conflict (33%), followed by human population growth rate (22%) and the amount of private land in row crops (18%). We then applied those rankings in a weighted linear summation to map the relative potential for elk–human conflict. Finally, we used white-tailed deer (Odocoileus virginianus) densities to identify areas where success of elk restoration may be hampered due to meningeal worm (Parelaphostrongylus tenuis) transmission. By combining results of the 3 spatial data layers (i.e., habitat model, elk–human conflict model, deer density), our model indicated that restoration sites located in west-central and north-central Arkansas were most favorable for reintroduction.

  16. 78 FR 5202 - Notice of Inventory Completion: Arkansas State University Museum, Jonesboro, AR

    Science.gov (United States)

    2013-01-24

    ... National Park Service Notice of Inventory Completion: Arkansas State University Museum, Jonesboro, AR AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Arkansas State University Museum... culturally affiliated with the human remains may contact the Arkansas State University Museum....

  17. 78 FR 5199 - Notice of Inventory Completion: Arkansas State University Museum, Jonesboro, AR

    Science.gov (United States)

    2013-01-24

    ... National Park Service Notice of Inventory Completion: Arkansas State University Museum, Jonesboro, AR AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Arkansas State University Museum... associated funerary objects may contact the Arkansas State University Museum. Repatriation of the...

  18. Time of travel of selected Arkansas streams

    Science.gov (United States)

    Lamb, T.E.

    1982-01-01

    Between 1971 and 1981, time-of-travel and dispersion measurements were made in 15 streams in Arkansas. Most of the streams studied were at or near base flow. Graphs are presented for predicting traveltime of solutes in segments of the streams studied. The relationship of time of passage and peak unit concentration to traveltime is presented for two of the streams. Examples of use and application of the data are given. (USGS)

  19. Success For Arkansas: Success for All Schools In Arkansas Continue Gains On Benchmark Exams

    Science.gov (United States)

    Success for All Foundation, 2004

    2004-01-01

    Success for All is the most extensively researched of all comprehensive reform models for Title I elementary schools. It incorporates scientifically based principles of reading, cooperative learning, professional development, tutoring, and family support. Arkansas elementary schools using the Success for All reading program continued to make …

  20. A Look at Arkansas' Children: Arkansas Kids Count Data Book 1997.

    Science.gov (United States)

    Dahlstrom, Sherryl M.; High, Rhonda L.

    This Kids Count data book provides information on indicators of the well-being of Arkansas' children. The report's introduction discusses factors contributing to increased attention to children and families, the need for broad-based community collaborations to address children and family needs, and cultural changes influencing families. Data…

  1. 75 FR 44982 - Arkansas Valley Conduit (AVC) and Long-Term Excess Capacity Master Contract, Fryingpan-Arkansas...

    Science.gov (United States)

    2010-07-30

    ..., Fryingpan-Arkansas Project (Fry-Ark Project) Colorado AGENCY: Bureau of Reclamation, Interior. ACTION... proposed feature of the Fryingpan-Arkansas (Fry-Ark) Project, and the issuance of an Excess Capacity Master...-Ark Project water in Pueblo Reservoir, a feature of the Fry-Ark Project. The water would be used...

  2. Arkansas' Anemometer Loan Program

    Energy Technology Data Exchange (ETDEWEB)

    Fernando Vego

    2012-10-11

    The measurement campaign had one year duration from 04/01/2011 to 03/31/2012 and was taken at 20m and 34m with NRG instrumentation. The data was analyzed weekly to check inconsistencies and validity and processed using Excel, Flexpro and Windographer standard Edition Version 2.04. The site analyzed is located in the Waldron, Arkansas in Scott County. It is an open site for most of the direction sectors with immediate roughness class of 1.5. It has seasonally directional winds, of which the most energetic come from the southern direction. The vertical wind profile shows moderate wind shear that varies by season as well.

  3. Small Works in Arkansas: How Poverty and the Size of Schools and School Districts Affect School Performance in Arkansas. Summary of Recent Research.

    Science.gov (United States)

    Rural School and Community Trust, Washington, DC.

    A study examined how Arkansas students' achievement is related to poverty, school and district size, and the interaction between these factors. Achievement test scores from grades 4, 5, 7, 8, and 9 in all Arkansas schools were supplied by the Arkansas Department of Education. Poverty levels were determined by percentage of students receiving…

  4. Aquifers of Arkansas: protection, management, and hydrologic and geochemical characteristics of groundwater resources in Arkansas

    Science.gov (United States)

    Kresse, Timothy M.; Hays, Phillip D.; Merriman, Katherine R.; Gillip, Jonathan A.; Fugitt, D. Todd; Spellman, Jane L.; Nottmeier, Anna M.; Westerman, Drew A.; Blackstock, Joshua M.; Battreal, James L.

    2014-01-01

    Sixteen aquifers in Arkansas that currently serve or have served as sources of water supply are described with respect to existing groundwater protection and management programs, geology, hydrologic characteristics, water use, water levels, deductive analysis, projections of hydrologic conditions, and water quality. State and Federal protection and management programs are described according to regulatory oversight, management strategies, and ambient groundwater-monitoring programs that currently (2013) are in place for assessing and protecting groundwater resources throughout the State.

  5. Final Critical Habitat for the Arkansas River Shiner (Notropis girardi)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Arkansas River Shiner (Notropis girardi) occur. The geographic extent includes New...

  6. Central Arkansas National Wildlife Refuge Complex: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Central Arkansas NWR Complex for the next 15 years. This plan outlines the Complex...

  7. 76 FR 44031 - Arkansas; Major Disaster and Related Determinations

    Science.gov (United States)

    2011-07-22

    ....046, Fire Management Assistance Grant; 97.048, Disaster Housing Assistance to Individuals and...--Disaster Housing Operations for Individuals and Households; 97.050, Presidentially Declared Disaster... SECURITY Federal Emergency Management Agency Arkansas; Major Disaster and Related Determinations...

  8. [Arkansas annual winter goose survey: December 10 & 11, 1979

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A table presents data gathered during the goose survey in Arkansas. Numbers of Canada Geese, Whitefronted Geese, resident geese, and BlueSnow Geese are included.

  9. [Arkansas annual winter goose survey: December 11 - 15, 1978

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A table presents data gathered during the goose survey in Arkansas. Numbers of Canada Geese, Whitefronted Geese, resident geese, and BlueSnow Geese are included.

  10. Fitness-for-duty program at Arkansas nuclear one

    International Nuclear Information System (INIS)

    The key events at Arkansas Power and Light Co. (AP and L) the fitness for duty (FFD) program since January 1981 are outlined. The sequential interface and impact of the US Nuclear Regulatory Commission (NRC) ruling, of the Edison Electric Institute (EEI)-published guidelines, and of the NUMARC commitment have played a key role in the continuing evolution of the FFD program at Arkansas Nuclear One (ANO). The major elements of the FFD program, difficulties encountered, and successful results are described

  11. 78 FR 72877 - Arkansas Electric Corporation v. Oklahoma Gas and Electric Company; Notice of Complaint

    Science.gov (United States)

    2013-12-04

    ... Energy Regulatory Commission Arkansas Electric Corporation v. Oklahoma Gas and Electric Company; Notice... Procedure of the Federal Energy Regulatory Commission (Commission), 18 CFR 385.206, Arkansas Electric Corporation (Complainant) filed a formal complaint against Oklahoma Gas and Electric Company...

  12. 78 FR 48716 - Notice of Availability of the Final Environmental Impact Statement for the Arkansas Valley...

    Science.gov (United States)

    2013-08-09

    ... Arkansas River Basin, groundwater, climate change, recreation biological resources, human environment... Valley Conduit and Long-Term Excess Capacity Master Contract, Fryingpan-Arkansas Project; Bent, Chaffee... statement (EIS) for the Arkansas Valley Conduit (AVC) and Long-Term Excess Capacity Contract,...

  13. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  14. Arkansas Superintendents Predict Curriculum for the Year 2000.

    Science.gov (United States)

    Vaupel, Carl F., Jr.; Sweat, Joseph P.

    1985-01-01

    Superintendents of 164 Arkansas small school districts predicted the importance of 20 selected academic courses/physical activities by the year 2000. Courses/activities ranked highest for 2000 were computer science, physics, soccer, economics, and composition. Study assumes collective wisdom or bias of superintendents will alter future secondary…

  15. Arkansas and the Southern Regional Education Board, December 2014

    Science.gov (United States)

    Southern Regional Education Board (SREB), 2014

    2014-01-01

    This report details Arkansas's participation in SREB programs and services from December 2013 through November 2014. Appropriations from member states support SREB's core operations and general services. SREB leverages the long-standing commitment of member states to attract external funding for an array of targeted projects for educational…

  16. Black bears in Arkansas: Characteristics of a successful translocation

    Science.gov (United States)

    Smith, Kimberly G.; Clark, Joseph D.

    1994-01-01

    In 1958, the Arkansas Game and Fish Commission began translocating black bears (Ursus americanus) from Minnesota to the Interior Highlands (Ozark and Ouachita mountains) of Arkansas where bears had been extirpated early in this century. This project continued for 11 years with little public imput, during which time an estimated 254 bears were released. We estimate there are now >2,500 bears in the Interior Highlands of Arkansas, Missouri, and Oklahoma, making it one of the most successful translocations of a Carnivora. Factors that contributed to the success include use of wild-captured animals, elimination of major factors associated with extirpation, release into prime habitats within the former range, multiple release sites, release of 20–40 animals/year for eight years, and release of mostly males prior to release of mostly females. Studies on two allopatric populations demonstrate that they are now diverging in some demographic characteristics, including litter size, cub survivorship, and adult sex-ratio. Translocation of black bears to the Interior Highlands is successful in terms of numbers of animals, but it will not be truly successful until people accept black bears as part of the regional fauna. To that end, those associated with management and research of bears in Arkansas are now focussing on public education and control of nuisance bears.

  17. State Minimum Core Curricula: Arkansas Institutions of Higher Education.

    Science.gov (United States)

    Arkansas State Dept. of Higher Education, Little Rock.

    State minimum core curricula for two-year and four-year colleges and universities have been approved by the Arkansas Board of Higher Education. Within the framework of the State Minimum Core, each state institution is required to propose 35 semester/credit hours from its institutional general education core to be recognized for purposes of the…

  18. State Minimum Core Curricula: Arkansas Institutions of Higher Education, 2000.

    Science.gov (United States)

    Arkansas State Dept. of Higher Education, Little Rock.

    This document provides state minimum core curricula for each two- and four-year institution of higher education in Arkansas, determined by the Department of Higher Education. Courses within this core are to apply toward the general education core curriculum requirements for baccalaureate degrees at state-supported institutions and should be fully…

  19. State Minimum Core Curricula: Arkansas Institutions of Higher Education, 2003.

    Science.gov (United States)

    Arkansas State Dept. of Higher Education, Little Rock.

    In 1990 the Arkansas State Board of Higher Education adopted guidelines for the development of state minimum core curriculum response to state legislation. This legislation provides that courses within the core shall apply to the general education core curriculum requirements for baccalaureate degrees at state-supported institutions and shall be…

  20. Project CAP. Boston Mountains Educational Cooperative, Greenland, Arkansas.

    Science.gov (United States)

    Hamilton, Jack A.; Leffler, Jeanne

    This description of career education activities in Greenland, Arkansas, was prepared as part of a study conducted to identify evaluated, exemplary career education activities which represent the best of the current career education programs and practices referred to in Public Law 93-380. (See CE 018 212 for the final report of this study.) This…

  1. Arkansas Solar Retrofit Guide. Greenhouses, Air Heaters and Water Heaters.

    Science.gov (United States)

    Skiles, Albert; Rose, Mary Jo

    Solar retrofits are devices of structures designed to be attached to existing buildings to augment their existing heating sources with solar energy. An investigation of how solar retrofits should be designed to suit the climate and resources of Arkansas is the subject of this report. Following an introduction (section 1), section 2 focuses on…

  2. Lithology, hydrologic characteristics, and water quality of the Arkansas River Valley alluvial aquifer in the vicinity of Van Buren, Arkansas

    Science.gov (United States)

    Kresse, Timothy M.; Westerman, Drew A.; Hart, Rheannon M.

    2015-01-01

    A study to assess the potential of the Arkansas River Valley alluvial aquifer in the vicinity of Van Buren, Arkansas, as a viable source of public-supply water was conducted by the U.S. Geological Survey in cooperation with the Little Rock, District, U.S. Army Corps of Engineers. An important study component was to identify possible changes in hydrologic conditions following installation of James W. Trimble Lock and Dam 13 (December 1969) on the Arkansas River near the study area. Data were gathered for the study in regard to the lithology, hydrologic characteristics, and water quality of the aquifer. Lithologic information was obtained from drillers’ logs of wells drilled from 1957 through 1959. Water-quality samples were collected from 10 irrigation wells and analyzed for inorganic constituents and pesticides. To evaluate the potential viability of the alluvial aquifer in the Van Buren area, these data were compared to similar stratigraphic, lithologic, and groundwater-quality data from the Arkansas River Valley alluvial aquifer at Dardanelle, Ark., where the aquifer provides a proven, productive, sole-source of public-supply water.

  3. The Arkansas Autism Developmental Disabilities Monitoring (AR ADDM) project: statewide autism surveillance in a rural state.

    Science.gov (United States)

    Lopez, Maya; Schulz, Eldon G; Baroud, Thaer; Hudson, Allison; Wilson, Mark

    2012-03-01

    In 2002, the Arkansas Autism and Developmental Disabilities Monitoring (AR ADDM) project collected data on the number and characteristics of resident children aged 8 years using a retrospective record review standardized methodology. This paper provides a first-look epidemiology of ASDs among 8 year old Arkansas children using data from the 2002 study year. Overall prevalence estimates, demographic distribution and a temporal lag from concerns identified to diagnosis of ASDs among 8 year olds in Arkansas were similar to that in other sites. Dissemination of information that promotes timely resolution of developmental concerns and improving educational services will benefit children with autism in Arkansas. PMID:22479981

  4. Middle Claiborne Aquifer: Alabama, Arkansas, Illinois, Kentucky, Louisiana, Missouri, Mississippi, Tennessee 2006-2008

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Digital hydrogeologic surface of the Middle Claiborne Aquifer in Alabama, Arkansas, Illinois, Kentucky, Louisiana, Missouri, Mississippi, Tennessee. The...

  5. Floods of Selected Streams in Arkansas, Spring 2008

    Science.gov (United States)

    Funkhouser, Jaysson E.; Eng, Ken

    2009-01-01

    Floods can cause loss of life and extensive destruction to property. Monitoring floods and understanding the reasons for their occurrence are the responsibility of many Federal agencies. The National Weather Service, the U.S. Army Corps of Engineers, and the U.S. Geological Survey are among the most visible of these agencies. Together, these three agencies collect and analyze floodflow information to better understand the variety of mechanisms that cause floods, and how the characteristics and frequencies of floods vary with time and location. The U.S. Geological Survey (USGS) has monitored and assessed the quantity of streamflow in our Nation's streams since the agency's inception in 1879. Because of ongoing collection and assessment of streamflow data, the USGS can provide information about a range of surface-water issues including the suitability of water for public supply and irrigation and the effects of agriculture and urbanization on streamflow. As part of its streamflow-data collection activities, the USGS measured streamflow in multiple streams during extreme flood events in Arkansas in the spring of 2008. The analysis of streamflow information collected during flood events such as these provides a scientific basis for decision making related to resource management and restoration. Additionally, this information can be used by water-resource managers to better define flood-hazard areas and to design bridges, culverts, dams, levees, and other structures. Water levels (stage) and streamflow (discharge) currently are being monitored in near real-time at approximately 150 locations in Arkansas. The streamflow-gaging stations measure and record hydrologic data at 15-minute or hourly intervals; the data then are transmitted through satellites to the USGS database and displayed on the internet every 1 to 4 hours. Streamflow-gaging stations in Arkansas are part of a network of over 7,500 active streamflow-gaging stations operated by the USGS throughout the United

  6. UPPER BUFFALO WILDERNESS AND BUFFALO ADDITION ROADLESS AREA, ARKANSAS.

    Science.gov (United States)

    Miller, Mary H.; Armstrong, Michelle K.

    1984-01-01

    The Upper Buffalo Wilderness and Buffalo Addition Roadless Area covers about 19 sq mi in the Ozark National Forest, Newton County, Arkansas. No metal-bearing minerals were observed during geologic mapping, and analyses for zinc and lead contents in surface rock and sediment samples from the study area are not anomalous. Exploratory drilling into the Boone Formation and (or) the Everton Formation will be necessary to evaluate the mineral-resource potential of zinc and lead in the study area.

  7. Submarine-fan sedimentation, Ouachita Mountains, Arkansas and Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    Moiola, R.J.; Shanmugam, G.

    1984-09-01

    More than 10,000 m (32,808 ft) of interbedded sandstones and shales comprise the Upper Mississippian and Lower Pennsylvanian flysch succession (Stanley, Jackfork, Johns Valley, Atoka) in the Ouachita Mountains of Arkansas and Oklahoma. Deposited primarily by turbidity current and hemipelagic processes in bathyal and abyssal water depths, these strata formed major submarine-fan complexes that prograded in a westward direction along the axis of an elongate remnant ocean basin that was associated with the collision and suturing of the North American and African-South American plates. A longitudinal fan system is visualized as the depositional framework for these strata, which were deposited in a setting analogous to the modern Bengal fan of the Indian Ocean. Facies analysis of the Jackfork formation indicates that inner fan deposits are present in the vicinity of Little Rock, Arkansas; middle fan channel and interchannel deposits occur at DeGray Dam and Friendship, Arkansas; and outer fan depositional-lobe deposits are present in southeastern Oklahoma. Boulder-bearing units (olistostromes), many with exotic clasts, were shed laterally into the Ouachita basin. They occur throughout the flysch succession and in all fan environments (i.e., inner, middle, and outer). This relationship may serve as a useful criterion for recognizing analogous longitudinal fan systems in the rock record.

  8. 78 FR 78398 - Notice and Request for Comments: LSC merger of the migrant service areas in Texas, Arkansas...

    Science.gov (United States)

    2013-12-26

    ... Notice and Request for Comments: LSC merger of the migrant service areas in Texas, Arkansas, Kentucky... Request for Comments--LSC merger of the migrant service areas in Texas, Arkansas, Kentucky, Louisiana..., Arkansas, Kentucky, Louisiana, Mississippi, Tennessee, and Alabama migrant service areas. Grants for...

  9. 78 FR 27306 - Radio Broadcasting Services; Dermott, Arkansas, and Cleveland, Mississippi

    Science.gov (United States)

    2013-05-10

    ... COMMISSION 47 CFR Part 73 Radio Broadcasting Services; Dermott, Arkansas, and Cleveland, Mississippi AGENCY... Delta Radio Network, LLC, substitutes FM Channel 224A for 289A at Dermott, Arkansas, and substitutes FM...-20110913AAK. Channel 224A can be allotted at Dermott with a site restriction of 3.5 km (2.2 miles)...

  10. "McLean v. Arkansas" (1982) and Beyond: Implications for Biology Professors

    Science.gov (United States)

    Bland, Mark W.; Moore, Randy

    2011-01-01

    To assess current trends of evolution instruction in high schools of the mid-South, we invited Arkansas high school biology teachers from across the state to respond to a survey designed to address this issue. We also asked students enrolled in a freshman-level, nonmajors biology course at a midsize public Arkansas university to recall their…

  11. Association of School-Based Influenza Vaccination Clinics and School Absenteeism--Arkansas, 2012-2013

    Science.gov (United States)

    Gicquelais, Rachel E.; Safi, Haytham; Butler, Sandra; Smith, Nathaniel; Haselow, Dirk T.

    2016-01-01

    Background: Influenza is a major cause of seasonal viral respiratory illness among school-aged children. Accordingly, the Arkansas Department of Health (ADH) coordinates >800 school-based influenza immunization clinics before each influenza season. We quantified the relationship between student influenza vaccination in Arkansas public schools…

  12. 77 FR 6711 - Approval and Promulgation of Implementation Plans; Arkansas; Infrastructure Requirements for the...

    Science.gov (United States)

    2012-02-09

    ... proposing to approve SIP revisions that modify the Arkansas PSD SIP to include nitrogen oxides (NO X ) as an... Greenhouse Gas Emitting-Sources in State Implementation Plans; Final Rule,'' 75 FR 82536 (December 30, 2010... Greenhouse Gas Tailoring Rule; Final Rule.'' 75 FR 31514 (June 3, 2010). The approved Arkansas SIP...

  13. 77 FR 47779 - Arkansas: Final Authorization of State Hazardous Waste Management Program Revision

    Science.gov (United States)

    2012-08-10

    ... FR 31756-31769 Arkansas Code of 1987 Annotated (A.C.A.) Treatment Sludges from Auto Sections 8-7-201... AGENCY 40 CFR Part 271 Arkansas: Final Authorization of State Hazardous Waste Management Program Revision... to the EPA for Final authorization of the changes to its hazardous waste program under the...

  14. The Arkansas Building Industry's Perceptions of Entry-Level Employee Work Competencies.

    Science.gov (United States)

    Gregson, James A.

    1989-01-01

    A study surveyed 100 (66 responses) employers in the Arkansas home building industry to determine the emphasis they place on affective, cognitive, and psychomotor skills. Although employers value affective work behaviors, the Arkansas building trades competency profiles used for curriculum development emphasize the psychomotor domain. (JOW)

  15. N Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The last of Hanfordqaodmasdkwaspemas7ajkqlsmdqpakldnzsdflss nine plutonium production reactors to be built was the N Reactor.This reactor was called a dual purpose...

  16. Status of Water Levels in Aquifers in the Nacatoch Sand of Southwestern and Northeastern Arkansas and the Tokio Formation of Southwestern Arkansas, February 2005

    Science.gov (United States)

    Schrader, T.P.

    2007-01-01

    The Nacatoch Sand and Tokio Formation aquifers in southwestern Arkansas and the Nacatoch Sand aquifer in northeastern Arkansas are sources of water for industrial, public supply, domestic, and agricultural uses. Potentiometric-surface maps were constructed from water-level measurements made in 60 wells completed in the Nacatoch Sand and 50 wells completed in the Tokio Formation during February 2005. Aquifers in the Nacatoch Sand and Tokio Formation are hereafter referred to as the Nacatoch aquifer and Tokio aquifer, respectively. The direction of ground-water flow in the Nacatoch aquifer in northeastern Arkansas generally is towards the southeast. The potentiometric high is located along the north and northwestern boundaries of the area. The direction of ground-water flow in the Nacatoch aquifer in southwestern Arkansas is towards the south-southeast in Little River, Miller, and Hempstead Counties and to the east-southeast in Nevada and Clark Counties. The potentiometric high is located within the outcrop area in north-central Hempstead County. A cone of depression exists in the Nacatoch aquifer at Hope in southeastern Hempstead County. The direction of ground-water flow in the Tokio aquifer in southwestern Arkansas generally is towards the south or southeast. The potentiometric high is within the outcrop area. An area of artesian flow exists in southeastern Pike, northeastern Hempstead, and northwestern Nevada Counties. One apparent cone of depression might exist northwest of Hope in Hempstead County. In northeastern Arkansas, withdrawals from the Nacatoch aquifer increased by 516 percent from 1965 to 2000. In southwestern Arkansas, withdrawals from Nacatoch aquifer and Tokio aquifer increased by 125 percent and 201 percent, respectively, from 1965 to 1980 and decreased by 93 percent and 80 percent, respectively, from 1980 to 2000. Long-term hydrographs were prepared for 10 wells in the study areas. Changes in water levels in some wells may be associated with

  17. Status of Water Levels in Aquifers in the Nacatoch Sand of Southwestern and Northeastern Arkansas and the Tokio Formation of Southwestern Arkansas, 1999

    Science.gov (United States)

    Schrader, Tony P.

    1999-01-01

    Nacatoch Sand and Tokio Formation aquifers in southwestern Arkansas and the Nacatoch Sand aquifer in northeastern Arkansas are a source of water for industrial, public supply, domestic, and agricultural uses. Potentiometric-surface maps were constructed from water-level measurements made in 59 wells completed in the Nacatoch Sand and 45 wells completed in the Tokio Formation from April through May 1999. The direction of ground-water flow in the aquifer in the Nacatoch Sand in northeastern Arkansas generally is towards the southeast. The potentiometric high is located along the north and northwestern boundaries. The direction of ground-water flow in the aquifer in the Nacatoch Sand in southwestern Arkansas is towards the south-southeast in Little River, Miller, and Hempstead Counties and to the east-southeast in Nevada and Clark Counties. The potentiometric high is located within the outcrop area in north-central Hempstead County. A cone of depression exists in the aquifer in the Nacatoch Sand at Hope in southeastern Hempstead County. The direction of ground-water flow in the aquifer in the Yokio Formation in southwestern Arkansas generally is towards the southeast. The potentiometric high is within the outcrop area. An area of artesian flow exists in southeastern Pike, northeastern Hempstead, and northwestern Nevada Counties. One apparent cone of depression might exist northwest of Hope in Hempstead County. In northeastern Arkansas, withdrawals from the Nacatoch Sand increased by 736 percent from 1965 to 1995. In southwestern Arkansas withdrawals from aquifers in the Nacatoch Sand and Yokio Formation increased by 125 percent and 201 percent, respectively, from 1965 to 1980 and decreased by 78 percent and 63 percent, respectively, from 1980 to 1995. Long-term hydrographs were prepared for 13 wells in the study area. Changes in water levels in some wells may be associated with changes in withdrawals from the respective aquifers.

  18. Dry season mean monthly flow and harmonic mean flow regression equations for selected ungaged basins in Arkansas

    Science.gov (United States)

    Breaker, Brian K.

    2015-01-01

    The U.S. Geological Survey, in cooperation with the Arkansas Department of Environmental Quality, Southwestern Energy, the Arkansas Natural Resources Commission, and the Arkansas Game and Fish Commission, developed regression equations for estimation of dry season mean monthly flows and harmonic mean flows that are representative of natural streamflow conditions at selected ungaged basins in Arkansas. Observed values of dry season mean monthly flow and harmonic mean flow computed from daily-mean flow data were used with basin characteristics to identify significant explanatory variables for multiple-linear-regression equations to estimate predicted values of dry season mean monthly flow and harmonic mean flow. Five dry season mean monthly flow regression equations and two harmonic mean flow regression equations were developed using dry season mean monthly flows and harmonic mean flows established for 91 and 93 U.S. Geological Survey continuous-record streamflow-gaging stations, respectively. The dry season in Arkansas is defined as the months of July through November for this study. For harmonic mean flow calculations and regression equations, the study area is composed of the Springfield-Salem Plateaus (Arkansas and Missouri), Boston Mountains, Arkansas Valley, Ouachita Mountains (Arkansas and Oklahoma), and West Gulf Coastal Plain (Arkansas) physiographic sections. All continuous-record streamflow-gaging stations used to compute dry season mean monthly flows were located within Arkansas.

  19. 77 FR 55430 - Arkansas Regulatory Program and Abandoned Mine Land Reclamation Plan

    Science.gov (United States)

    2012-09-10

    ... grammatical changes, correct punctuation, revise dates, and delete and add citations. The proposed amendment consists of substantive changes to Arkansas's regulations regarding: Subchapter A--General; Subchapter F... grammatical changes, correct punctuation, revise dates, update addresses, and delete and add...

  20. Arkansas State Briefing Book for low-level radioactive waste management

    International Nuclear Information System (INIS)

    The Arkansas State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. This report contains a profile of low-level radioactive waste generators in Arkansas. The profile is the result of a survey of NRC licensees in Arkansas. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Arkansas

  1. Mississippi River Valley Alluvial Aquifer, Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Tennessee; 2006-2008

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Outcrop and subcrop extent of the Mississippi River Valley Alluvial Aquifer in Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, and Tennessee.

  2. Arkansas State Briefing Book for low-level radioactive-waste management

    International Nuclear Information System (INIS)

    The Arkansas State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Arkansas. The profile is the result of a survey of NRC licensees in Arkansas. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Arkansas

  3. Middle Wilcox Aquifer: Alabama, Arkansas, Illinois, Kentucky, Louisiana, Missouri, Mississippi, Tennessee 2006-2008

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Digital hydrogeologic surface of the Middle Wolcox Aquifer in Alabama, Arkansas, Illinois, Kentucky, Louisiana, Missouri, Mississippi, Tennessee. The hydrogeologic...

  4. Upper Claiborne Aquifer: Alabama, Arkansas, Louisiana, Missouri, Mississippi, Tennessee 2006-2008

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Digital hydrogeologic surface of the Upper Claiborne Aquifer in Arkansas, Alabama, Louisiana, Missouri, Mississippi, and Tennessee. The hydrogeologic unit dataset...

  5. Middle Claiborne Confining Unit: Alabama, Arkansas, Kentucky, Louisiana, Missouri, Mississippi, Tennessee 2006-2008

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Digital hydrogeologic surface of the Middle Claiborne Confining Unit in Alabama, Arkansas, Kentucky, Louisiana, Missouri, Mississippi, Tennessee. The hydrogeologic...

  6. An Evaluation of Ecosystem Restoration Options for Grand Prairie Region of Arkansas

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Evaluation of Ecosystem Restoration and Management Options covers the hydrogeomorphic analysis (HGM) for Grand Prairie Region of Arkansas. This three step...

  7. Vicksburg-Jackson Confining Unit: Alabama, Arkansas, Louisiana, Missouri, Mississippi, Tennessee 2006-2008

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Digital hydrogeologic surface of the Vicksburg-Jackson Confining Unit in Arkansas, Alabama, Louisiana, Missouri, Mississippi, and Tennessee. The hydrogeologic unit...

  8. Employment Discrimination Based on Sexual Orientation and Gender Identity in Arkansas

    OpenAIRE

    Mallory, Christy; Sears, Brad

    2015-01-01

    None of the approximately 47,000 LGBT workers in Arkansas are explicitly protected from discrimination under local, state or federal laws. If sexual orientation and gender identity were added to existing statewide non-discrimination laws, 22 more complaints would be filed in Arkansas each year. The cost of enforcing those complaints would be negligible, and would not require additional court or administrative staff.

  9. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  10. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  11. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  12. Folic acid and the decline in neural tube defects in Arkansas.

    Science.gov (United States)

    Mosley, Bridget S; Hobbs, Charlotte A; Flowers, Bettye S; Smith, Veronica; Robbins, James M

    2007-04-01

    Folic acid has been shown to reduce the risk of pregnancies affected by neural tube defects (NTDs) by as much as 70%. Cereal grains sold in the U.S. have been fortified with folic acid since 1998. The Arkansas Reproductive Health Monitoring System and the Arkansas Folic Acid Coalition have encouraged use of folic acid and monitored the impact of increased consumption of folic acid among Arkansans. NTDs in Arkansas have declined 40% since intervention programs were implemented. The greatest decline has been observed among white and Hispanic women. Efforts to encourage folic acid consumption should continue to target Arkansas women. NTDs include anencephaly and spina bifida. These birth defects result from incomplete closure of the fetal neural tube during the first month of pregnancy. Infants with anencephaly are born without all or most of their brain and die within a few days of life. Infants with spina bifida have varying degrees of impairment ranging from little noticeable disability to severe, lifelong disability. Folic acid, when taken in supplement form has been shown to reduce the risk of a pregnancy affected by a neural tube defect by as much as 70%. As a result of this finding, the U.S. Federal Drug Administration mandated that cereal grains sold in this country be fortified with at least 140 mcg of folic acid per 100 grams of grain by January 1, 1998. Prior to mandatory fortification, the March of Dimes and the U.S. Public Health Service released statements encouraging all women of reproductive age who are capable of becoming pregnant to take 400 mcg 'of synthetic folic acid daily. The Arkansas Reproductive Health Monitoring System (ARHMS) has monitored rates of NTDs in Arkansas since 1980. ARHMS is the lead agency of the Arkansas Folic Acid Coalition whose mission is to encourage folic acid use among all Arkansas women of reproductive age. In this report, we summarize efforts by ARHMS and the Arkansas Folic Acid Coalition to increase the awareness and

  13. Folic acid and the decline in neural tube defects in Arkansas.

    Science.gov (United States)

    Mosley, Bridget S; Hobbs, Charlotte A; Flowers, Bettye S; Smith, Veronica; Robbins, James M

    2007-04-01

    Folic acid has been shown to reduce the risk of pregnancies affected by neural tube defects (NTDs) by as much as 70%. Cereal grains sold in the U.S. have been fortified with folic acid since 1998. The Arkansas Reproductive Health Monitoring System and the Arkansas Folic Acid Coalition have encouraged use of folic acid and monitored the impact of increased consumption of folic acid among Arkansans. NTDs in Arkansas have declined 40% since intervention programs were implemented. The greatest decline has been observed among white and Hispanic women. Efforts to encourage folic acid consumption should continue to target Arkansas women. NTDs include anencephaly and spina bifida. These birth defects result from incomplete closure of the fetal neural tube during the first month of pregnancy. Infants with anencephaly are born without all or most of their brain and die within a few days of life. Infants with spina bifida have varying degrees of impairment ranging from little noticeable disability to severe, lifelong disability. Folic acid, when taken in supplement form has been shown to reduce the risk of a pregnancy affected by a neural tube defect by as much as 70%. As a result of this finding, the U.S. Federal Drug Administration mandated that cereal grains sold in this country be fortified with at least 140 mcg of folic acid per 100 grams of grain by January 1, 1998. Prior to mandatory fortification, the March of Dimes and the U.S. Public Health Service released statements encouraging all women of reproductive age who are capable of becoming pregnant to take 400 mcg 'of synthetic folic acid daily. The Arkansas Reproductive Health Monitoring System (ARHMS) has monitored rates of NTDs in Arkansas since 1980. ARHMS is the lead agency of the Arkansas Folic Acid Coalition whose mission is to encourage folic acid use among all Arkansas women of reproductive age. In this report, we summarize efforts by ARHMS and the Arkansas Folic Acid Coalition to increase the awareness and

  14. Research reactors

    International Nuclear Information System (INIS)

    This article proposes an overview of research reactors, i.e. nuclear reactors of less than 100 MW. Generally, these reactors are used as neutron generators for basic research in matter sciences and for technological research as a support to power reactors. The author proposes an overview of the general design of research reactors in terms of core size, of number of fissions, of neutron flow, of neutron space distribution. He outlines that this design is a compromise between a compact enough core, a sufficient experiment volume, and high enough power densities without affecting neutron performance or its experimental use. The author evokes the safety framework (same regulations as for power reactors, more constraining measures after Fukushima, international bodies). He presents the main characteristics and operation of the two families which represent almost all research reactors; firstly, heavy water reactors (photos, drawings and figures illustrate different examples); and secondly light water moderated and cooled reactors with a distinction between open core pool reactors like Melusine and Triton, pool reactors with containment, experimental fast breeder reactors (Rapsodie, the Russian BOR 60, the Chinese CEFR). The author describes the main uses of research reactors: basic research, applied and technological research, safety tests, production of radio-isotopes for medicine and industry, analysis of elements present under the form of traces at very low concentrations, non destructive testing, doping of silicon mono-crystalline ingots. The author then discusses the relationship between research reactors and non proliferation, and finally evokes perspectives (decrease of the number of research reactors in the world, the Jules Horowitz project)

  15. Reactor physics and reactor computations

    International Nuclear Information System (INIS)

    Mathematical methods and computer calculations for nuclear and thermonuclear reactor kinetics, reactor physics, neutron transport theory, core lattice parameters, waste treatment by transmutation, breeding, nuclear and thermonuclear fuels are the main interests of the conference

  16. The fishes of Hot Springs National Park, Arkansas, 2003

    Science.gov (United States)

    Petersen, James C.; Justus, B.G.

    2005-01-01

    Fish communities were sampled from eight sites within Hot Springs National Park. Fish were collected by seining and electrofishing during base-flow periods in July and October 2003. All individuals were identified to species. More than 1,020 individuals were collected, representing 24 species. The number of species collected at the sites ranged from 5 to 19. Central stoneroller, orangebelly darter, and longear sunfish were among the more abundant fish species at most sites. These species are typical of small streams in this area. An expected species list incorrectly listed 35 species because of incorrect species range or habitat requirements. Upon revising this list, the inventory yielded 24 of the 51 expected species (47 percent). No species collected in 2003 were federally-listed threatened or endangered species. However, two species collected at Hot Springs National Park may be of special interest to National Park Service managers and others. The Ouachita madtom is endemic to the Ouachita Mountains and is listed as a species of special concern by the Arkansas Natural Heritage Commission. The grass carp, which is a native of eastern Asia, is present in Ricks Pond; one individual was collected and no other grass carp were observed. The introduction of grass carp into the United States is a controversial issue because of possible (but undocumented) harmful effects on native species and habitats.

  17. Ooid mineralogy and diagenesis of upper Mississippian Pitkin Formation, Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Heydari, E.; Snelling, R.D.; Dawson, W.C.; Machain, M.L. (Louisiana State Univ., Baton Rouge (USA))

    1989-08-01

    The Pitkin formation is a marine oolitic-bioclastic limestone exhibiting shoal, lagoonal, beach, and tidal-channel facies. Ooids formed on the Pitkin carbonate shelf show lateral and vertical variations in original mineralogy. In a section south of Mountain View, Arkansas, the lower marine shoal and shoreface facies are composed of originally aragonitic ooids. These ooids are replaced by neomorphic calcite and exhibit elevated strontium and low magnesium concentrations. The overlying lagoonal facies are composed of originally calcite ooids that have retained their original radial fabrics. These ooids exhibit low strontium and high magnesium concentration. Ooids in sections to the west of Mountain View are all calcitic. Early diagenesis of the formation is dominated by marine cementation. Postdepositional diagenesis encompasses extensive dissolution of originally aragonite and magnesian calcite components, precipitation of a late unzoned ferroan calcite, and minor amounts of saddle dolomite. Grainstone units lack any intergranular porosity. Pressure solution contacts among grains in grainstones are generally uncommon. Cementation alone is responsible for destruction of all of the original porosity in these rocks. Intensive pressure solution is observed only in packstone units not affected by early marine cementation.

  18. Reactor building

    International Nuclear Information System (INIS)

    The whole reactor building is accommodated in a shaft and is sealed level with the earth's surface by a building ceiling, which provides protection against penetration due to external effects. The building ceiling is supported on walls of the reactor building, which line the shaft and transfer the vertical components of forces to the foundations. The thickness of the walls is designed to withstand horizontal pressure waves in the floor. The building ceiling has an opening above the reactor, which must be closed by cover plates. Operating equipment for the reactor can be situated above the building ceiling. (orig./HP)

  19. Geologic map of the Murray Quadrangle, Newton County, Arkansas

    Science.gov (United States)

    Hudson, Mark R.; Turner, Kenzie J.

    2016-07-06

    This map summarizes the geology of the Murray quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area is on the southern flank of the Ozark dome, an uplift that has the oldest rocks exposed at its center, in Missouri. Physiographically, the Murray quadrangle is within the Boston Mountains, a high plateau region underlain by Pennsylvanian sandstones and shales. Valleys of the Buffalo River and Little Buffalo River and their tributaries expose an approximately 1,600-ft-thick (488-meter-thick) sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. The Buffalo National River, a park that encompasses the Buffalo River and adjacent land that is administered by the National Park Service is present at the northwestern edge of the quadrangle.Mapping for this study was carried out by field inspection of numerous sites and was compiled as a 1:24,000 geographic information system (GIS) database. Locations and elevation of sites were determined with the aid of a global positioning satellite receiver and a hand-held barometric altimeter that was frequently recalibrated at points of known elevation. Hill-shade relief and slope maps derived from a U.S. Geological Survey 10-meter digital elevation model as well as orthophotographs were used to help trace ledge-forming units between field traverses within the Upper Mississippian and Pennsylvanian part of the stratigraphic sequence. Strike and dip of beds were typically measured along stream drainages or at well-exposed ledges. Structure contours, constructed on the top of the Boone Formation and the base of a prominent sandstone unit within the Bloyd Formation, were drawn based on the elevations of field sites on these contacts well as other limiting information for their minimum elevations above hilltops or their maximum elevations below valley bottoms.

  20. Sample Curriculum Model, Grade 1, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 1 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  1. Sample Grade Level Benchmarks, Grades 5-8, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document presents the application and use of mathematics learning proposed by the Arkansas curriculum frameworks for grades 5-8. The standards are presented in chart form and organized into five strands: (1) number sense, properties, and operations; (2) geometry and spatial sense; (3) measurement; (4) data analysis, statistics, and…

  2. Sample Grade Level Benchmarks, Grades K-4, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document presents the application and use of mathematics learning proposed by the Arkansas curriculum frameworks for grades K-4. The standards are presented in chart form and organized into five strands: (1) number sense, properties, and operations; (2) geometry and spatial sense; (3) measurement; (4) data analysis, statistics, and…

  3. Sample Curriculum Model, Grade 3, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 3 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  4. Sample Curriculum Model, Grade 4, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 4 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  5. Sample Curriculum Model, Grade K, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for Kindergarten mathematics based on the 1998 Arkansas State Mathematics Framework. The model is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra,…

  6. Sample Curriculum Model, Grade 5, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 5 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  7. Sample Curriculum Model, Grade 2, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 2 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  8. Sample Curriculum Model, Grade 7, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 7 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  9. Sample Curriculum Model, Grade 6, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 6 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  10. Sample Curriculum Model, Grade 8, Based on the 1998 Arkansas State Mathematics Framework.

    Science.gov (United States)

    Arkansas State Dept. of Education, Little Rock.

    This document consists of a sample curriculum model for grade 8 mathematics based on the 1998 Arkansas State Mathematics Framework. The document is divided into five sections: (1) Number Sense, Properties, and Operations; (2) Geometry and Spatial Sense; (3) Measurement; (4) Data Analysis, Statistics, and Probability; and (5) Patterns, Algebra, and…

  11. Impact of Spina Bifida on Parental Caregivers: Findings from a Survey of Arkansas Families

    Science.gov (United States)

    Grosse, Scott D.; Flores, Alina L.; Ouyang, Lijing; Robbins, James M.; Tilford, John M.

    2009-01-01

    The well-being of caregivers of children with spina bifida and other conditions is an important topic. We interviewed the primary caregivers of 98 children aged 0-17 years with spina bifida sampled from a population-based birth defects registry in Arkansas and the caregivers of 49 unaffected children. Measures of caregiver well-being were compared…

  12. Examination of the rice blast pathogen population diversity in Arkansas, USA – Stable or Unstable?

    Science.gov (United States)

    Over the past 17 years, isolates of Pyricularia oryzae (= P. grisea) have been recovered from commercial rice fields in Arkansas. Annual samples have typically included 100–500 isolates recovered from 5 to 10 cultivars from 10 different counties with the majority of the isolates being recovered from...

  13. Ready to Lead? A Study of Arkansas and Louisiana Charter School Principals' Leadership Skills

    Science.gov (United States)

    Price, Creshun Anjal

    2013-01-01

    The purpose of this study was to explore the relationship of Arkansas and Louisiana district conversion and open-enrollment charter school principals' background characteristics, leadership skills, and school success. A quantitative methodology was used to test the research questions prescribed in the study. Data was collected using a survey. The…

  14. Pharmaceuticals and other organic chemicals in selected north-central and northwestern Arkansas streams

    Science.gov (United States)

    Haggard, B.E.; Galloway, J.M.; Green, W.R.; Meyer, M.T.

    2006-01-01

    Recently, our attention has focused on the low level detection of many antibiotics, pharmaceuticals, and other organic chemicals in water resources. The limited studies available suggest that urban or rural streams receiving wastewater effluent are more susceptible to contamination. The purpose of this study was to evaluate the occurrence of antibiotics, pharmaceuticals, and other organic chemicals at 18 sites on seven selected streams in Arkansas, USA, during March, April, and August 2004. Water samples were collected upstream and downstream from the influence of effluent discharges in northwestern Arkansas and at one site on a relatively undeveloped stream in north-central Arkansas. At least one antibiotic, pharmaceutical, or other organic chemical was detected at all sites, except at Spavinaw Creek near Mayesville, Arkansas. The greatest number of detections was observed at Mud Creek downstream from an effluent discharge, including 31 pharmaceuticals and other organic chemicals. The detection of these chemicals occurred in higher frequency at sites downstream from effluent discharges compared to those sites upstream from effluent discharges; total chemical concentration was also greater downstream. Wastewater effluent discharge increased the concentrations of detergent metabolites, fire retardants, fragrances and flavors, and steroids in these streams. Antibiotics and associated degradation products were only found at two streams downstream from effluent discharges. Overall, 42 of the 108 chemicals targeted in this study were found in water samples from at least one site, and the most frequently detected organic chemicals included caffeine, phenol, para-cresol, and acetyl hexamethyl tetrahydro naphthalene (AHTN). ?? ASA, CSSA, SSSA.

  15. Teacher Pension Incentives, Retirement Behavior, and Potential for Reform in Arkansas. Conference Paper 2009-10

    Science.gov (United States)

    Costrell, Robert M.; McGee, Josh B.

    2009-01-01

    In this paper, we present an analysis of the Arkansas Teacher Retirement System (ATRS) pension plan and an empirical investigation of the behavioral response to that plan, as well as to a possible reform plan. We begin by describing the plan parameters and discussing the incentives these parameters create. We then estimate the effect of pension…

  16. Teacher Pension Incentives, Retirement Behavior, and Potential for Reform in Arkansas

    Science.gov (United States)

    Costrell, Robert M.; McGee, Josh B.

    2010-01-01

    The authors analyze the Arkansas teacher pension plan and empirically gauge the behavioral response to incentives embedded in that plan and to possible reforms. The pattern of pension wealth accrual creates sharp incentives to work until eligible for early or normal retirement, often in one's early fifties, and to separate shortly thereafter. We…

  17. Field evaluation of four spatial repellent devices against Arkansas rice-land mosquitoes

    Science.gov (United States)

    Four commercially available spatial repellent devices were tested in a rice land habitat near Stuttgart, Arkansas after semi-field level assessments had been made at the Center for Medical, Agricultural, and Veterinary Entomology, ARS, USDA in Gainesville, FL. OFF! Clip-On® (a.i. metofluthrin, S.C....

  18. Drought and deluge: Effects of recent climate variability on groundwater levels in eastern Arkansas

    Science.gov (United States)

    Czarnecki, John B.; Schrader, T.P.

    2013-01-01

    Arkansas experienced wide extremes in climate variability during the period of 2005 to 2010, recording the largest annual precipitation ever recorded in the State (100.05 inches) in 2009. Many weather stations across the State reported between 80 to 90 inches of rainfall in 2009. For comparison, the average annual precipitation in Little Rock, Arkansas, for the period 1878 to 2010 was 47.1 inches. In contrast, 2005 and 2010 were the 7th and 14th driest years on record in Little Rock with 34.55 and 36.52 inches, respectively; both tied as the hottest years ever recorded in Arkansas. The wettest year on record in Little Rock (2009) was interspersed within these dry years, with a total of 81.79 inches. Fifteen weather stations within the State ranked 2009 as the wettest year on record. Extremes in annual precipitation rates may lead to greater variability in groundwater recharge rates and water use, particularly in the agricultural areas in eastern Arkansas that rely heavily on groundwater produced from the Mississippi River Valley alluvial aquifer (hereafter referred to as the alluvial aquifer). How does this variability affect the groundwater system and water use therein? Are the effects of this variability discernable in measured water levels in wells? Czarnecki and Schrader examined these questions and provided some insights, the results of which are presented here.

  19. The Effect of Performance Pay in Little Rock, Arkansas on Student Achievement. Research Brief

    Science.gov (United States)

    Winters, Marcus; Greene, Jay; Ritter, Gary; Marsh, Ryan

    2008-01-01

    This paper examines evidence from a performance-pay program implemented in five Little Rock, Arkansas elementary schools between 2004 and 2007. Using a differences-in-differences approach, the evidence shows that students whose teachers were eligible for performance pay made substantially larger test score gains in math, reading, and language than…

  20. Child Care Needs of Mothers in Arkansas' Labor Force: A Statistical Study.

    Science.gov (United States)

    Arkansas Advocates for Children and Families, Little Rock.

    The major purpose of this paper is to increase employers' awareness of the impact that the rising number of working mothers has had on the need for day care in Arkansas as a whole and in their specific business locales. It is hoped that employers will be motivated to investigate and evaluate the advantages of providing some form of day care…

  1. Human Resources Promotes Diversity and Inclusiveness at the University of Arkansas

    Science.gov (United States)

    Taylor, Barbara

    2007-01-01

    Advancing diversity and inclusiveness on campus is certainly a top priority for many institutions today. The question often is not "Should we promote diversity in our campus community?" but rather "How do we go about doing it?" At the University of Arkansas, the chancellor had long declared that diversity was his first and most important goal.…

  2. 76 FR 36142 - Arkansas; Amendment No. 6 to Notice of a Major Disaster Declaration

    Science.gov (United States)

    2011-06-21

    ... Unemployment Assistance (DUA); 97.046, Fire Management Assistance Grant; 97.048, Disaster Housing Assistance to... Assistance--Disaster Housing Operations for Individuals and Households; 97.050, Presidentially Declared... SECURITY Federal Emergency Management Agency Arkansas; Amendment No. 6 to Notice of a Major...

  3. 76 FR 37360 - Arkansas; Amendment No. 7 to Notice of a Major Disaster Declaration

    Science.gov (United States)

    2011-06-27

    ..., Disaster Unemployment Assistance (DUA); 97.046, Fire Management Assistance Grant; 97.048, Disaster Housing... Declared Disaster Assistance--Disaster Housing Operations for Individuals and Households; 97.050... SECURITY Federal Emergency Management Agency Arkansas; Amendment No. 7 to Notice of a Major...

  4. Compact Reactor

    International Nuclear Information System (INIS)

    Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date

  5. NEUTRONIC REACTOR

    Science.gov (United States)

    Anderson, H.L.

    1960-09-20

    A nuclear reactor is described comprising fissionable material dispersed in graphite blocks, helium filling the voids of the blocks and the spaces therebetween, and means other than the helium in thermal conductive contact with the graphite for removing heat.

  6. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  7. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  8. Unpublished Interim Digital Geologic Map of Hot Springs National Park and Vicinity, Arkansas (NPS, GRD, GRI, HOSP, HOSP digital map) adapted from the interim Arkansas Geological Survey DGM-HSR-003 by Johnson and Hanson (2011)

    Data.gov (United States)

    National Park Service, Department of the Interior — The Unpublished Interim Digital Geologic Map of Hot Springs National Park and Vicinity, Arkansas is composed of GIS data layers complete with ArcMap 9.3 layer...

  9. NUCLEAR REACTOR

    Science.gov (United States)

    Anderson, C.R.

    1962-07-24

    A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)

  10. Nuclear reactor

    International Nuclear Information System (INIS)

    In order to reduce neutron embrittlement of the pressue vessel of an LWR, blanked off elements are fitted at the edge of the reactor core, with the same dimensions as the fuel elements. They are parallel to each other, and to the edge of the reactor taking the place of fuel rods, and are plates of neutron-absorbing material (stainless steel, boron steel, borated Al). (HP)

  11. 78 FR 28003 - In the Matter of Entergy Arkansas and Entergy Operations, Arkansas Nuclear One, Units 1 and 2...

    Science.gov (United States)

    2013-05-13

    ...,'' was published in the Federal Register on January 3, 2013 (78 FR 328). No comments or hearing requests... the Director of the Office of Nuclear Reactor Regulation satisfactory documentary evidence that EAL... (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13077A237), to reflect the...

  12. Arkansas: a leading laboratory for health care payment and delivery system reform.

    Science.gov (United States)

    Bachrach, Deborah; du Pont, Lammot; Lipson, Mindy

    2014-08-01

    As states' Medicaid programs continue to evolve from traditional fee-for-service to value-based health care delivery, there is growing recognition that systemwide multipayer approaches provide the market power needed to address the triple aim of improved patient care, improved health of populations, and reduced costs. Federal initiatives, such as the State Innovation Model grant program, make significant funds available for states seeking to transform their health care systems. In crafting their reform strategies, states can learn from early innovators. This issue brief focuses on one such state: Arkansas. Insights and lessons from the Arkansas Health Care Payment Improvement Initiative (AHCPII) suggest that progress is best gained through an inclusive, deliberative process facilitated by committed leadership, a shared agreement on root problems and opportunities for improvement, and a strategy grounded in the state's particular health care landscape. PMID:25204031

  13. Arkansas: a leading laboratory for health care payment and delivery system reform.

    Science.gov (United States)

    Bachrach, Deborah; du Pont, Lammot; Lipson, Mindy

    2014-08-01

    As states' Medicaid programs continue to evolve from traditional fee-for-service to value-based health care delivery, there is growing recognition that systemwide multipayer approaches provide the market power needed to address the triple aim of improved patient care, improved health of populations, and reduced costs. Federal initiatives, such as the State Innovation Model grant program, make significant funds available for states seeking to transform their health care systems. In crafting their reform strategies, states can learn from early innovators. This issue brief focuses on one such state: Arkansas. Insights and lessons from the Arkansas Health Care Payment Improvement Initiative (AHCPII) suggest that progress is best gained through an inclusive, deliberative process facilitated by committed leadership, a shared agreement on root problems and opportunities for improvement, and a strategy grounded in the state's particular health care landscape.

  14. Building Partnerships With Rural Arkansas Faith Communities to Promote Veterans’ Mental Health: Lessons Learned

    Science.gov (United States)

    Sullivan, Greer; Hunt, Justin; Haynes, Tiffany F.; Bryant, Keneshia; Cheney, Ann M.; Pyne, Jeffrey M.; Reaves, Christina; Sullivan, Steve; Lewis, Caleb; Barnes, Bonita; Barnes, Michael; Hudson, Cliff; Jegley, Susan; Larkin, Bridgette; Russell, Shane; White, Penny; Gilmore, LaNissa; Claypoole, Sterling; Smith, Rev. Johnny; Richison, Ruth

    2014-01-01

    Background The Mental Health–Clergy Partnership Program established partnerships between institutional (Department of Veterans’ Affairs [VA] chaplains, mental health providers) and community (local clergy, parishioners) groups to develop programs to assist rural veterans with mental health needs. Objectives Describe the development, challenges, and lessons learned from the Mental Health–Clergy Partnership Program in three Arkansas towns between 2009 and 2012. Methods Researchers identified three rural Arkansas sites, established local advisory boards, and obtained quantitative ratings of the extent to which partnerships were participatory. Results Partnerships seemed to become more participatory over time. Each site developed distinctive programs with variation in fidelity to original program goals. Challenges included developing trust and maintaining racial diversity in local program leadership. Conclusions Academics can partner with local faith communities to create unique programs that benefit the mental health of returning veterans. Research is needed to determine the effectiveness of community based programs, especially relative to typical “top-down” outreach approaches. PMID:24859098

  15. A new species of Sellaphora (Sellaphoraceae) from Hannaberry Lake, Arkansas, U.S.A.

    OpenAIRE

    Enache, Mihaela D.; Potapova, Marina

    2009-01-01

    A new small-size species of Sellaphora was found in sediments from Hannaberry Lake, Arkansas, during the National Lakes Assessment project conducted by the United States Environmental Protection Agency. The species was studied with light microscopy and scanning electron microscopy. It differs from previously reported Sellaphora species by its small and delicate frustule with striation irresolvable in light microscopy. Here we present details on its morphology and size variation and report the...

  16. Arkansas and Louisiana Aeromagnetic and Gravity Maps and Data - A Website for Distribution of Data

    Science.gov (United States)

    Bankey, Viki; Daniels, David L.

    2008-01-01

    This report contains digital data, image files, and text files describing data formats for aeromagnetic and gravity data used to compile the State aeromagnetic and gravity maps of Arkansas and Louisiana. The digital files include grids, images, ArcInfo, and Geosoft compatible files. In some of the data folders, ASCII files with the extension 'txt' describe the format and contents of the data files. Read the 'txt' files before using the data files.

  17. Molecular Subtype Analyses of Campylobacter spp. from Arkansas and California Poultry Operations

    OpenAIRE

    Hiett, K. L; Stern, N. J.; Fedorka-Cray, P.; Cox, N. A.; Musgrove, M. T.; Ladely, S.

    2002-01-01

    Campylobacter isolates from diverse samples within broiler production and processing environments were typed by using flaA short variable region DNA sequence analysis. Sixteen flocks from four different farms representing two broiler producers in Arkansas and California were analyzed. Fourteen of the flocks (87.5%) were Campylobacter-positive; two remained negative throughout the 6-week rearing period. In general, multiple clones were present within a flock. Additionally, clones found within ...

  18. Atmospheric Contributors to Heavy Rainfall Events in the Arkansas-Red River Basin

    OpenAIRE

    McCorkle, Taylor A.; Skylar S. Williams; Pfeiffer, Timothy A.; Basara, Jeffrey B.

    2016-01-01

    This study analyzed the top 1% 24-hour rainfall events from 1994 to 2013 at eight climatological sites that represent the east to west precipitation gradient across the Arkansas-Red River Basin in North America. A total of 131 cases were identified and subsequently classified on the synoptic-scale, mesoscale, and local-scale to compile a climatological analysis of these extreme, heavy rainfall events based on atmospheric forcings. For each location, the prominent midtropospheric pattern, meso...

  19. Molecular Detection of Rickettsia Species Within Ticks (Acari: Ixodidae) Collected from Arkansas United States.

    Science.gov (United States)

    Trout Fryxell, R T; Steelman, C D; Szalanski, A L; Billingsley, P M; Williamson, P C

    2015-05-01

    Rocky Mountain spotted fever (RMSF), caused by the etiological agent Rickettsia rickettsii, is the most severe and frequently reported rickettsial illness in the United States, and is commonly diagnosed throughout the southeast. With the discoveries of Rickettsia parkeri and other spotted fever group rickettsiae (SFGR) in ticks, it remains inconclusive if the cases reported as RMSF are truly caused by R. rickettsii or other SFGR. Arkansas reports one of the highest incidence rates of RMSF in the country; consequently, to identify the rickettsiae in Arkansas, 1,731 ticks, 250 white-tailed deer, and 189 canines were screened by polymerase chain reaction (PCR) for the rickettsial genes gltA, rompB, and ompA. None of the white-tailed deer were positive, while two of the canines (1.1%) and 502 (29.0%) of the ticks were PCR positive. Five different tick species were PCR positive: 244 (37%) Amblyomma americanum L., 130 (38%) Ixodes scapularis Say, 65 (39%) Amblyomma maculatum (Koch), 30 (9%) Rhipicephalus sanguineus Latreille, 7 (4%) Dermacentor variabilis Say, and 26 (44%) unidentified Amblyomma ticks. None of the sequenced products were homologous to R. rickettsii. The most common Rickettsia via rompB amplification was Rickettsia montanensis and nonpathogenic Candidatus Rickettsia amblyommii, whereas with ompA amplification the most common Rickettsia was Ca. R. amblyommii. Many tick specimens collected in northwest Arkansas were PCR positive and these were commonly A. americanum harboring Ca. R. amblyommii, a currently nonpathogenic Rickettsia. Data reported here indicate that pathogenic R. rickettsii was absent from these ticks and suggest by extension that other SFGR are likely the causative agents for Arkansas diagnosed RMSF cases.

  20. Arthropods of Steel Creek, Buffalo National River, Arkansas. III. Heteroptera (Insecta: Hemiptera)

    OpenAIRE

    Skvarla, Michael Joseph; Fisher, Danielle M.; Dowling, Ashley P.G.

    2016-01-01

    Abstract Background This is the third in a series of papers detailing the terrestrial arthropods collected during an intensive survey of a site near Steel Creek campground along the Buffalo National River in Arkansas. The survey was conducted over a period of eight and a half months using twelve trap types – Malaise traps, canopy traps (upper and lower collector), Lindgren multifunnel traps (black, green, and purple), pan traps (blue, purple, red, white, and yellow), and pitfall traps – and B...

  1. Terrestrial arthropods of Steel Creek, Buffalo National River, Arkansas. II. Sawflies (Insecta: Hymenoptera: " Symphyta ")

    OpenAIRE

    Skvarla, Michael Joseph; Smith, David R.; Fisher, Danielle M.; Dowling, Ashley P.G.

    2016-01-01

    Abstract Background This is the second in a series of papers detailing the terrestrial arthropods collected during an intensive survey of a site near Steel Creek campground along the Buffalo National River in Arkansas. The survey was conducted over a period of eight and a half months using twelve trap types – Malaise traps, canopy traps (upper and lower collector), Lindgren multifunnel traps (black, green, and purple), pan traps (blue, purple, red, white, and yellow), and pitfall traps – and ...

  2. Sonochemical Reactors.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  3. Methods and applications of electrical simulation in ground-water studies in the lower Arkansas and Verdigris River Valleys, Arkansas and Oklahoma

    Science.gov (United States)

    Bedinger, M.S.; Reed, J.E.; Wells, C.J.; Swafford, B.F.

    1970-01-01

    The Arkansas River Multiple-Purpose Plan will provide year-round navigation on the Arkansas River from near its mouth to Muskogee, Okla., and on the Verdigris River from Muskogee to Catoosa, Okla. The altered regimen in the Arkansas and Verdigris Rivers will affect ground-water conditions in the adjacent alluvial aquifers. In 1957 the U.S. Geological Survey and U.S. Army Corps of Engineers entered into a cooperative agreement for a comprehensive ground-water study of the lower Arkansas and Verdigris River valleys. At the request of the Corps of Engineers, the Geological Survey agreed to provide (1) basic ground-water data before, during, and after construction of the Multiple-Purpose Plan and (2) interpretation and projections of postconstruction ground-water conditions. The data collected were used by the Corps of Engineers in preliminary foundation and excavation estimates and by the Geological Survey as the basis for defining the hydrologic properties of, and the ground-water conditions in, the aquifer. The projections of postconstruction ground-water conditions were used by the Corps of Engineers in the planning, design, construction, and operation of the Multiple-Purpose Plan. Analysis and projections of ground-water conditions were made by use of electrical analog models. These models use the analogy between the flow of electricity in a resistance-capacitance circuit and the flow of a liquid in a porous and permeable medium. Verification provides a test of the validity of the analog to perform as the aquifer would, within the range of historic forces. The verification process consists of simulating the action of historic forces which have acted upon the aquifer and of duplicating the aquifer response with the analog. The areal distribution of accretion can be treated as an unknown and can be determined by analog simulation of the piezometric surface in an aquifer. Comparison of accretion with depth to piezometric surface below land surface shows that

  4. Reactor container

    International Nuclear Information System (INIS)

    A reactor container has a suppression chamber partitioned by concrete side walls, a reactor pedestal and a diaphragm floor. A plurality of partitioning walls are disposed in circumferential direction each at an interval inside the suppression chamber, so that independent chambers in a state being divided into plurality are formed inside the suppression chamber. The partition walls are formed from the bottom portion of the suppression chamber up to the diaphragm floor to isolate pool water in a divided state. Operation platforms are formed above the suppression chamber and connected to an access port. Upon conducting maintenance, inspection or repairing, a pump is disposed in the independent chamber to transfer pool water therein to one or a plurality of other independent chambers to make it vacant. (I.N.)

  5. NEUTRONIC REACTORS

    Science.gov (United States)

    Anderson, J.B.

    1960-01-01

    A reactor is described which comprises a tank, a plurality of coaxial steel sleeves in the tank, a mass of water in the tank, and wire grids in abutting relationship within a plurality of elongated parallel channels within the steel sleeves, the wire being provided with a plurality of bends in the same plane forming adjacent parallel sections between bends, and the sections of adjacent grids being normally disposed relative to each other.

  6. Notes from the Field: Cluster of Tuberculosis Cases Among Marshallese Persons Residing in Arkansas - 2014-2015.

    Science.gov (United States)

    Rothfeldt, Laura Lester; Patil, Naveen; Haselow, Dirk T; Williams, Sandy Hainline; Wheeler, J Gary; Mukasa, Leonard N

    2016-01-01

    During early September 2014, the Arkansas Department of Health identified an increased number of tuberculosis (TB) cases among a unique population in a well-circumscribed geographical area in northwest Arkansas. The Compact of Free Association Act of 1985 (Public Law 99-239, amended in 2003 by Public Law 108-188) established the Republic of the Marshall Islands (RMI) as an independent nation, and persons from the RMI can travel freely (with valid RMI passport) to and from the United States as nonimmigrants without visas (1). Marshallese started settling in northwest Arkansas during the early 1990s because of employment and educational opportunities (2). According to the 2010 Census, an estimated 4,300 Marshallese resided in Arkansas (2), mostly within one county which ranked 6th in the United States for counties with the highest percentage of Native Hawaiians and Other Pacific Islanders (3). It is estimated that this number has been growing steadily each year since the 2010 Census; however, obtaining an accurate count is difficult. The RMI is a TB high-incidence country, with a case-rate of 212.7 per 100,000 persons for 2014, whereas the case-rate was 3.1 per 100,000 persons in Arkansas and 2.9 per 100,000 persons in the United States (4,5). Screening for either active TB or latent TB infection (LTBI) is not required for Marshallese entry to the United States (1). PMID:27560201

  7. The Natural Divisions of Arkansas: A Three Week Unit. Classroom Guide. Recommended for High School Level Social Studies, Earth Science and Biological Science Classes.

    Science.gov (United States)

    Foti, Thomas L.

    This unit is designed to (1) acquaint the student with Arkansas, (2) provide information on what an environment (natural system) is, and (3) provide information on how people relate to the environment as a whole. Natural systems and natural divisions (geographical areas) of Arkansas are described. Included in several sections are questions to…

  8. "There Were High Hopes and High Projections:" Examining the Social Construction of Target Populations in the Policy Design of the Arkansas Lottery Legislation

    Science.gov (United States)

    Copeland, Kristopher

    2013-01-01

    Lottery policies have been created by many states to generate additional funds to support public initiatives, such as higher education scholarships. In 2009, Arkansas adopted a lottery to generate higher education scholarships. The purpose of this qualitative case study was to examine the Arkansas state lottery policy design process to better…

  9. Nuclear research reactors

    International Nuclear Information System (INIS)

    It's presented data about nuclear research reactors in the world, retrieved from the Sien (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: research reactors by countries; research reactors by type; research reactors by fuel and research reactors by purpose. (E.G.)

  10. Nuclear reactor

    International Nuclear Information System (INIS)

    A nuclear reactor is described in which the core components, including fuel-rod assemblies, control-rod assemblies, fertile rod-assemblies, and removable shielding assemblies, are supported by a plurality of separate inlet modular units. These units are referred to as inlet module units to distinguish them from the modules of the upper internals of the reactor. The modular units are supported, each removable independently of the others, in liners in the supporting structure for the lower internals of the reactor. The core assemblies are removably supported in integral receptacles or sockets of the modular units. The liners, units, sockets and assemblies have inlet openings for entry of the fluid. The modular units are each removably mounted in the liners with fluid seals interposed between the opening in the liner and inlet module into which the fluid enters in the upper and lower portion of the liner. Each assembly is similarly mounted in a corresponding receptacle with fluid seals interposed between the openings where the fluid enters in the lower portion of the receptacle or fitting closely in these regions. As fluid flows along each core assembly a pressure drop is produced along the fluid so that the fluid which emerges from each core assembly is at a lower pressure than the fluid which enters the core assembly. However because of the seals interposed in the mountings of the units and assemblies the pressures above and below the units and assemblies are balanced and the units are held in the liners and the assemblies are held in the receptacles by their weights as they have a higher specific gravity than the fluid. The low-pressure spaces between each module and its liner and between each core assembly and its module is vented to the low-pressure regions of the vessel to assure that fluid which leaks through the seals does not accumulate and destroy the hydraulic balance

  11. Nuclear reactor physics course for reactor operators

    International Nuclear Information System (INIS)

    The education and training of nuclear reactor operators is important to guarantee the safe operation of present and future nuclear reactors. Therefore, a course on basic 'Nuclear reactor physics' in the initial and continuous training of reactor operators has proven to be indispensable. In most countries, such training also results from the direct request from the safety authorities to assure the high level of competence of the staff in nuclear reactors. The aim of the basic course on 'Nuclear Reactor Physics for reactor operators' is to provide the reactor operators with a basic understanding of the main concepts relevant to nuclear reactors. Seen the education level of the participants, mathematical derivations are simplified and reduced to a minimum, but not completely eliminated

  12. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  13. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  14. Aerial gamma ray and magnetic survey: Mississippi and Florida airborne survey, Russellville quadrangle, Arkansas

    International Nuclear Information System (INIS)

    The Russellville quadrangle in north central Arkansas overlies thick Paleozoic sediments of the Arkoma Basin. These Paleozoics dominate surface exposure except where covered by Quaternary alluvial materials. Examination of available literature shows no known uranium deposits (or occurrences) within the quadrangle. Eighty-eight groups of uranium samples were defined as anomalies and are discussed briefly. None were considered significant, and most appeared to be of cultural origin. Magnetic data show character that suggest structural and/or lithologic complexity, but imply relatively deep-seated sources

  15. Reactor container

    International Nuclear Information System (INIS)

    Purpose: To prevent shocks exerted on a vent head due to pool-swell caused within a pressure suppression chamber (disposed in a torus configuration around the dry well) upon loss of coolant accident in BWR type reactors. Constitution: The following relationship is established between the volume V (m3) of a dry well and the ruptured opening area A (m2) at the boundary expected upon loss of coolant accident: V >= 30340 (m) x A Then, the volume of the dry well is made larger than the ruptured open area, that is, the steam flow rate of leaking coolants upon loss of coolant accident to decrease the pressure rise in the dry well at the initial state where loss of coolant accident is resulted. Accordingly, the pressure of non-compressive gases jetted out from the lower end of the downcomer to the pool water is decreased to suppress the pool-swell. (Ikeda, J.)

  16. Occurrence and distribution of dissolved solids, selenium, and uranium in groundwater and surface water in the Arkansas River Basin from the headwaters to Coolidge, Kansas, 1970-2009

    Science.gov (United States)

    Miller, Lisa D.; Watts, Kenneth R.; Ortiz, Roderick F.; ,

    2010-01-01

    In 2007, the U.S. Geological Survey (USGS), in cooperation with City of Aurora, Colorado Springs Utilities, Colorado Water Conservation Board, Lower Arkansas Valley Water Conservancy District, Pueblo Board of Water Works, Southeastern Colorado Water Activity Enterprise, Southeastern Colorado Water Conservancy District, and Upper Arkansas Water Conservancy District began a retrospective evaluation to characterize the occurrence and distribution of dissolved-solids (DS), selenium, and uranium concentrations in groundwater and surface water in the Arkansas River Basin based on available water-quality data collected by several agencies. This report summarizes and characterizes available DS, dissolved-selenium, and dissolved-uranium concentrations in groundwater and surface water for 1970-2009 and describes DS, dissolved-selenium, and dissolved-uranium loads in surface water along the main-stem Arkansas River and selected tributary and diversion sites from the headwaters near Leadville, Colorado, to the USGS 07137500 Arkansas River near Coolidge, Kansas (Ark Coolidge), streamgage, a drainage area of 25,410 square miles. Dissolved-solids concentrations varied spatially in groundwater and surface water in the Arkansas River Basin. Dissolved-solids concentrations in groundwater from Quaternary alluvial, glacial drift, and wind-laid deposits (HSU 1) increased downgradient with median values of about 220 mg/L in the Upper Arkansas subbasin (Arkansas River Basin from the headwaters to Pueblo Reservoir) to about 3,400 mg/L in the Lower Arkansas subbasin (Arkansas River Basin from John Martin Reservoir to Ark Coolidge). Dissolved-solids concentrations in the Arkansas River also increased substantially in the downstream direction between the USGS 07086000 Arkansas River at Granite, Colorado (Ark Granite), and Ark Coolidge streamgages. Based on periodic data collected from 1976-2007, median DS concentrations in the Arkansas River ranged from about 64 mg/L at Ark Granite to about

  17. Water quality of least-impaired lakes in eastern and southern Arkansas.

    Science.gov (United States)

    Justus, Billy

    2010-09-01

    A three-phased study identified one least-impaired (reference) lake for each of four Arkansas lake classifications: three classifications in the Mississippi Alluvial Plain (MAP) ecoregion and a fourth classification in the South Central Plains (SCP) ecoregion. Water quality at three of the least-impaired lakes generally was comparable and also was comparable to water quality from Kansas and Missouri reference lakes and Texas least-impaired lakes. Water quality of one least-impaired lake in the MAP ecoregion was not as good as water quality in other least-impaired lakes in Arkansas or in the three other states: a probable consequence of all lakes in that classification having a designated use as a source of irrigation water. Chemical and physical conditions for all four lake classifications were at times naturally harsh as limnological characteristics changed temporally. As a consequence of allochthonous organic material, oxbow lakes isolated within watersheds comprised of swamps were susceptible to low dissolved oxygen concentrations to the extent that conditions would be limiting to some aquatic biota. Also, pH in lakes in the SCP ecoregion was lakes exceeded that of shallow lakes. N/P ratios and trophic state indices may be less effective for assessing water quality for shallow lakes (lakes because there is an increased exposure of sediment (and associated phosphorus) to disturbance and light in the former. PMID:19705289

  18. Curriculum alignment and higher order thinking in introductory biology in Arkansas public two-year colleges

    Science.gov (United States)

    Crandall, Elizabeth Diane

    This dissertation identified the cognitive levels of lecture objectives, lab objectives, and test questions in introductory majors' biology. The study group included courses offered by 27 faculty members at 18 of the 22 community colleges in Arkansas. Using Bloom's Taxonomy to identify cognitive levels, the median lecture learning outcomes were at level 2 (Comprehension) and test assessments at Level 1 (Knowledge). Lab learning outcomes were determined to have a median of level 3 (Analysis). A correlation analysis was performed using SPSS software to determine if there was an association between the Bloom's level of lecture objectives and test assessments. The only significant difference found was at the Analysis level, or Bloom's level 4 (p=.043). Correlation analyses were run for two other data sets. Years of college teaching experience and hours of training in writing objectives and assessments were compared to the Bloom's Taxonomy level of lecture objectives and test items. No significant difference was found for either of these independent variables. This dissertation provides Arkansas two-year college biology faculty with baseline information about the levels of cognitive skills that are required in freshman biology for majors courses. It can serve to initiate conversations about where we are compared to a national study, where we need to be, and how we get there.

  19. EPSPS gene amplification in glyphosate-resistant in Italian ryegrass (Lolium perenne ssp. multiflorum) populations from Arkansas, USA

    Science.gov (United States)

    Glyphosate-resistant Italian ryegrass was detected in Arkansas, USA in 2007. In 2014, 45 populations were confirmed resistant in eight counties across the state. The level of resistance and resistance mechanisms in six populations was studied to assess the severity of the problem and identify altern...

  20. User's manual for FORAR: a stand model for composition and growth of upland forests of southern Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Mielke, D. L.; Shugart, H. H.; West, D. C.

    1977-04-01

    This report is a user's manual for FORAR, a computer model simulating stand growth and composition of upland forests of south central Arkansas. The model computes: the number and biomass of each tree species, and the dbh, age, and species of each individual tree on a 1/12-ha circular plot.

  1. The Effect of Performance-Pay in Little Rock, Arkansas on Student Achievement. Working Paper 2008-02

    Science.gov (United States)

    Winters, Marcus; Greene, Jay P.; Ritter, Gary; Marsh, Ryan

    2008-01-01

    This paper examines evidence from a performance-pay program implemented in five Little Rock, Arkansas elementary schools between 2004 and 2007. Using a differences-in-differences approach, the evidence shows that students whose teachers were eligible for performance pay made substantially larger test score gains in math, reading, and language than…

  2. 75 FR 36538 - Arkansas: Final Authorization of State-initiated Changes and Incorporation by Reference of State...

    Science.gov (United States)

    2010-06-28

    ... August 15, 2007, Federal Register authorization documents for Arkansas. The Solid Waste Disposal Act, as...''. 260.10 ``Solid waste management unit'' No Federal analog. or ``SWMU''''. 260.20(b) intro 260.20(b... and Ecology at 64 FR 63209-63213. (APC&E) Regulation Number 23 (Hazardous Waste Management)...

  3. Research Nuclear Reactors

    International Nuclear Information System (INIS)

    Published in English and in French, this large report first proposes an overview of the use and history of research nuclear reactors. It discusses their definition, and presents the various types of research reactors which can be either related to nuclear power (critical mock-ups, material test reactors, safety test reactors, training reactors, prototypes), or to research (basic research, industry, health), or to specific particle physics phenomena (neutron diffraction, isotope production, neutron activation, neutron radiography, semiconductor doping). It reports the history of the French research reactors by distinguishing the first atomic pile (ZOE), and the activities and achievements during the fifties, the sixties and the seventies. It also addresses the development of instrumentation for research reactors (neutron, thermal, mechanical and fission gas release measurements). The other parts of the report concern the validation of neutronics calculations for different reactors (the EOLE water critical mock-up, the MASURCA air critical mock-up dedicated to fast neutron reactor study, the MINERVE water critical mock-up, the CALIBAN pulsed research reactor), the testing of materials under irradiation (OSIRIS reactor, laboratories associated with research reactors, the Jules Horowitz reactor and its experimental programs and related devices, irradiation of materials with ion beams), the investigation of accident situations (on the CABRI, Phebus, Silene and Jules Horowitz reactors). The last part proposes a worldwide overview of research reactors

  4. Reactor Physics Training

    International Nuclear Information System (INIS)

    University courses in nuclear reactor physics at the universities consist of a theoretical description of the physics and technology of nuclear reactors. In order to demonstrate the basic concepts in reactor physics, training exercises in nuclear reactor installations are also desirable. Since the number of reactor facilities is however strongly decreasing in Europe, it becomes difficult to offer to students a means for demonstrating the basic concepts in reactor physics by performing training exercises in nuclear installations. Universities do not generally possess the capabilities for performing training exercises. Therefore, SCK-CEN offers universities the possibility to perform (on a commercial basis) training exercises at its infrastructure consisting of two research reactors (BR1 and VENUS). Besides the organisation of training exercises in the framework of university courses, SCK-CEN also organizes theoretical courses in reactor physics for the education and training of nuclear reactor operators. It is indeed a very important subject to guarantee the safe operation of present and future nuclear reactors. In this framework, an understanding of the fundamental principles of nuclear reactor physics is also necessary for reactor operators. Therefore, the organisation of a basic Nuclear reactor physics course at the level of reactor operators in the initial and continuous training of reactor operators has proven to be indispensable. In most countries, such training also results from the direct request from the safety authorities to assure the high level of competence of the staff in nuclear reactors. The objectives this activity are: (1) to provide training and education activities in reactor physics for university students and (2) to organise courses in nuclear reactor physics for reactor operators

  5. Geodatabase of the available top and bottom surface datasets that represent the Edwards-Trinity aquifer system, Arkansas, Oklahoma, and Texas

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This geodatabase contains the spatial datasets that represent the Edwards-Trinity aquifer system in the States of Arkansas, Oklahoma, and Texas. Included are: (1)...

  6. Safeguarding research reactors

    International Nuclear Information System (INIS)

    The report is organized in four sections, including the introduction. The second section contains a discussion of the characteristics and attributes of research reactors important to safeguards. In this section, research reactors are described according to their power level, if greater than 25 thermal megawatts, or according to each fuel type. This descriptive discussion includes both reactor and reactor fuel information of a generic nature, according to the following categories. 1. Research reactors with more than 25 megawatts thermal power, 2. Plate fuelled reactors, 3. Assembly fuelled reactors. 4. Research reactors fuelled with individual rods. 5. Disk fuelled reactors, and 6. Research reactors fuelled with aqueous homogeneous fuel. The third section consists of a brief discussion of general IAEA safeguards as they apply to research reactors. This section is based on IAEA safeguards implementation documents and technical reports that are used to establish Agency-State agreements and facility attachments. The fourth and last section describes inspection activities at research reactors necessary to meet Agency objectives. The scope of the activities extends to both pre and post inspection as well as the on-site inspection and includes the examination of records and reports relative to reactor operation and to receipts, shipments and certain internal transfers, periodic verification of fresh fuel, spent fuel and core fuel, activities related to containment and surveillance, and other selected activities, depending on the reactor

  7. A COLLABORATIVE LEARNING MATRIX FOR COMBINING SCIENCE WITH STAKEHOLDER INVOLVEMENT TO PRIORITIZE WATERSHED IMPLEMENTATION IN ARKANSAS' NONPOINT SOURCE STATE MANAGEMENT PLAN

    OpenAIRE

    ROBERT MORGAN; MARTY MATLOCK

    2008-01-01

    In 2004, the Ecological Engineering Group at the University of Arkansas received a grant to update Arkansas' nonpoint source pollution (NPS) management program. A stakeholder involvement process was developed that used collaborative learning (CL) and comparative risk assessment (CRA) to prioritise watersheds for NPS implementation. The relative ecological risk posed by nonpoint pollution to each watershed was assessed and values assigned using available water quality, GIS, and demographic dat...

  8. Demographics of Same-sex Couples in Arkansas, Missouri, Nebraska, North Dakota, and South Dakota: Analyses of the 2013 American Community Survey

    OpenAIRE

    Gates, Gary J.

    2015-01-01

    Analyzing data from the 2013 US American Community Survey, this report considers the demographic, economic, and geographic characteristics of same-sex couples (married and unmarried), especially those raising children, in Arkansas, Missouri, Nebraska, North Dakota, and South Dakota. Comparisons are made with their different-sex counterparts. In Arkansas, Missouri, Nebraska, North Dakota, and South Dakota, as of 2013, there are an estimated 19652 same-sex couples. An estimated 12% of these cou...

  9. Size distribution of planktonic autotrophy and microheterotrophy in DeGray Reservoir, Arkansas

    International Nuclear Information System (INIS)

    Naturally occurring assemblages of phytoplankton and bacterioplankton were radiolabelled with sodium 14C-bicarbonate and sodium 3H-acetate and size fractionated to determine the size structure of planktonic autotrophy and microheterotrophy in DeGray Reservoir, an oligotrophic impoundment of the Caddo River in south-central Arkansas. Size distributions of autotrophy and microheterotrophy were remarkably uniform seasonally, vertically within the water column, and along the longitudinal axis of the reservoir despite significant changes in environmental conditions. Planktonic autotrophy was dominated by small algal cells with usually >50% of the photosynthetic carbon uptake accounted for by organisms 75% of the planktonic microheterotrophy. Longitudinal patterns in autotrophic and microheterotrophic activities associated with >3-μm and >1-μm size fractions, respectively, suggest an uplake to downlake shift from riverine to lacustrine environmental influences within the reservoir. 83 references, 7 figures

  10. Ecological Factors Affecting the Distribution of Woody Vegetation Near the Arkansas River, Tulsa County

    Directory of Open Access Journals (Sweden)

    Anne Wanamnaker Long

    2004-12-01

    Full Text Available Ecological factors affecting plant distribution were studied over different rock strata and slope exposures above the Arkansas River, Tulsa County. Here the Wann sandstone caprock is underlain by the Iola limestone formation. The vegetation was analyzed taxonomically by a complete collection throughout one growing season. Belt transects crossing rock strata on all slope exposures permitted computation of parameters summarized by an Importance Percentage for each woody species. Differences in species populations and degree of mesophytism exist on the slope exposures. Sandstone upland dominants are post and blackjack oaks. Smoke-tree, rare in Oklahoma, and chinquapin oak are closely associated in limestone microhabitats, where each occupies a separate niche. The smoke-tree, of disjunct distribution, appears to be a relict of widespread occurrence in past geologic periods. Its survival with limited ecological amplitude is due to the continuance of the microhabitats to which it is so well adapted.

  11. Digital surfaces and thicknesses of selected hydrogeologic units within the Ozark Plateaus aquifer system, northwestern Arkansas

    Science.gov (United States)

    Czarnecki, John B.; Bolyard, Susan E.; Hart, Rheannon M.; Clark, Jimmy M.

    2014-01-01

    Digital surfaces and thicknesses of nine hydrogeologic units of the Ozark Plateaus aquifer system from land surface to the top of the Gunter Sandstone in northwestern Arkansas were created using geophysical logs, drillers’ logs, geologist-interpreted formation tops, and previously published maps. The 6,040 square mile study area in the Ozark Plateaus Province includes Benton, Washington, Carroll, Madison, Boone, Newton, Marion, and Searcy Counties. The top of each hydrogeologic unit delineated on geophysical logs was based partly on previously published reports and maps and also from drillers’ logs. These logs were then used as a basis to contour digital surfaces showing the top and thickness of the Fayetteville Shale, the Boone Formation, the Chattanooga Shale, the Everton Formation, the Powell Dolomite, the Cotter Dolomite, the Roubidoux Formation, the Gasconade Dolomite, and the Gunter Sandstone.

  12. Geochemical and geostatistical evaluation, Arkansas Canyon Planning Unit, Fremont and Custer Counties, Colorado

    Science.gov (United States)

    Weiland, E.F.; Connors, R.A.; Robinson, M.L.; Lindemann, J.W.; Meyer, W.T.

    1982-01-01

    A mineral assessment of the Arkansas Canyon Planning Unit was undertaken by Barringer Resources Inc., under the terms of contract YA-553-CTO-100 with the Bureau of Land Management, Colorado State Office. The study was based on a geochemical-geostatistical survey in which 700 stream sediment samples were collected and analyzed for 25 elements. Geochemical results were interpreted by statistical processing which included factor, discriminant, multiple regression and characteristic analysis. The major deposit types evaluated were massive sulfide-base metal, sedimentary and magmatic uranium, thorium vein, magmatic segregation, and carbonatite related deposits. Results of the single element data and multivariate geostatistical analysis indicate that limited potential exists for base metal mineralization near the Horseshoe, El Plomo, and Green Mountain Mines. Thirty areas are considered to be anomalous with regard to one or more of the geochemical parameters evaluated during this study. The evaluation of carbonatite related mineralization was restricted due to the lack of geochemical data specific to this environment.

  13. Geologic map of the west-central Buffalo National River region, northern Arkansas

    Science.gov (United States)

    Hudson, Mark R.; Turner, Kenzie J.

    2014-01-01

    This map summarizes the geology of the west-central Buffalo National River region in the Ozark Plateaus region of northern Arkansas. Geologically, the region lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the map area spans the Springfield Plateau, a topographic surface generally held up by Mississippian cherty limestone and the higher Boston Mountains to the south, held up by Pennsylvanian rocks. The Buffalo River flows eastward through the map area, enhancing bedrock erosion of an approximately 1,600-ft- (490-m-) thick sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. Quaternary surficial units are present as alluvial deposits along major streams, including a series of terrace deposits from the Buffalo River, as well as colluvium and landslide deposits mantling bedrock on hillslopes.

  14. Effects of recent climate variability on groundwater levels in eastern Arkansas

    Science.gov (United States)

    Czarnecki, John B.; Schrader, T.P.

    2013-01-01

    Water-level fluctuations in wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas were compared to variability in annual precipitation, an indicator of climate variability. The wettest year on record in Little Rock, Arkansas, occurred in 2009 with 81.79 inches of precipitation compared to an average of 47.1 inches per year. In contrast, 2005 and 2010 were the 7th and 14th driest years on record with 34.55 and 36.52 inches per year, respectively. This variability in precipitation was reflected in water-level altitude changes between 2004 and 2008 and 2006 and 2010. Generally, drier conditions between 2004 and 2008 led to an average decline in water levels of 1.62 feet, whereas wetter conditions between 2006 and 2010 led to an average rise in water levels of 1.36 feet. Drier periods likely resulted in less recharge compared to wetter periods. Groundwater use from the alluvial aquifer peaked in 2000 and has since declined, in part, because of conservation measures and substantial reduction in aquifer saturated thickness. Groundwater-flow model results showed some areas of the alluvial aquifer simulated as dry in 2010, indicating a reduced capacity of the alluvial aquifer to produce water in those areas. Additional factors affecting groundwater use include the types of crops grown in an area and the availabitiliy of crop subsidies. Real-time continuous water-level measurements in wells allow for a more accurate assessment of the effect of variability in precipitation and water use than periodic water-level measurements.

  15. The road to tuberculosis (Mycobacterium tuberculosis elimination in Arkansas; a re-examination of risk groups.

    Directory of Open Access Journals (Sweden)

    Anna Berzkalns

    Full Text Available OBJECTIVES: This study was conducted to generate knowledge useful for developing public health interventions for more effective tuberculosis control in Arkansas. METHODS: The study population included 429 culture-confirmed reported cases (January 1, 2004-December 31, 2010. Mycobacterium tuberculosis genotyping data were used to identify cases likely due to recent transmission (clustered versus reactivation (non-clustered. Poisson regression models estimated average decline rate in incidence over time and assessed the significance of differences between subpopulations. A multinomial logistic model examined differences between clustered and non-clustered incidence. RESULTS: A significant average annual percent decline was found for the overall incidence of culture-confirmed (9%; 95% CI: 5.5%, 16.9%, clustered (6%; 95% CI: 0.5%, 11.6%, and non-clustered tuberculosis cases (12%; 95% CI: 7.6%, 15.9%. However, declines varied among demographic groups. Significant declines in clustered incidence were only observed in males, non-Hispanic blacks, 65 years and older, and the rural population. CONCLUSIONS: These findings suggest that the Arkansas tuberculosis control program must target both traditional and non-traditional risk groups for successful tuberculosis elimination. The present study also demonstrates that a thorough analysis of TB trends in different population subgroups of a given geographic region or state can lead to the identification of non-traditional risk factors for TB transmission. Similar studies in other low incidence populations would provide beneficial data for how to control and eventually eliminate TB in the U.S.

  16. Reactor Physics Programme

    Energy Technology Data Exchange (ETDEWEB)

    De Raedt, C

    2000-07-01

    The Reactor Physics and Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis on reactor fuel. This expertise is applied within the Reactor Physics and MYRRHA Research Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments. Progress and achievements in 1999 in the following areas are reported on: (1) investigations on the use of military plutonium in commercial power reactors; (2) neutron and gamma calculations performed for BR-2 and for other reactors; (3) the updating of neutron and gamma cross-section libraries; (4) the implementation of reactor codes; (6) the management of the UNIX workstations; and (6) fuel cycle studies.

  17. Ship propulsion reactors technology

    International Nuclear Information System (INIS)

    This paper takes the state of the art on ship propulsion reactors technology. The french research programs with the corresponding technological stakes, the reactors specifications and advantages are detailed. (A.L.B.)

  18. Undergraduate reactor control experiment

    International Nuclear Information System (INIS)

    A sequence of reactor and related experiments has been a central element of a senior-level laboratory course at Pennsylvania State University (Penn State) for more than 20 yr. A new experiment has been developed where the students program and operate a computer controller that manipulates the speed of a secondary control rod to regulate TRIGA reactor power. Elementary feedback control theory is introduced to explain the experiment, which emphasizes the nonlinear aspect of reactor control where power level changes are equivalent to a change in control loop gain. Digital control of nuclear reactors has become more visible at Penn State with the replacement of the original analog-based TRIGA reactor control console with a modern computer-based digital control console. Several TRIGA reactor dynamics experiments, which comprise half of the three-credit laboratory course, lead to the control experiment finale: (a) digital simulation, (b) control rod calibration, (c) reactor pulsing, (d) reactivity oscillator, and (e) reactor noise

  19. Reactor System Design

    International Nuclear Information System (INIS)

    SMART NPP(Nuclear Power Plant) has been developed for duel purpose, electricity generation and energy supply for seawater desalination. The objective of this project IS to design the reactor system of SMART pilot plant(SMART-P) which will be built and operated for the integrated technology verification of SMART. SMART-P is an integral reactor in which primary components of reactor coolant system are enclosed in single pressure vessel without connecting pipes. The major components installed within a vessel includes a core, twelve steam generator cassettes, a low-temperature self pressurizer, twelve control rod drives, and two main coolant pumps. SMART-P reactor system design was categorized to the reactor coe design, fluid system design, reactor mechanical design, major component design and MMIS design. Reactor safety -analysis and performance analysis were performed for developed SMART=P reactor system. Also, the preparation of safety analysis report, and the technical support for licensing acquisition are performed

  20. Statistical summary of selected water-quality data (water years 1975 through 1985) for Arkansas rivers and streams

    Science.gov (United States)

    Petersen, J.C.

    1988-01-01

    Descriptive statistics were calculated for selected water quality data for 116 water quality stations on Arkansas rivers and streams. Water quality properties summarized included pH, specific conductance, dissolved oxygen, total alkalinity, total hardness, common dissolved constituents, phosphorus, nitrogen, biochemical oxygen demand, bacteria, turbidity, suspended sediment, and several trace metals. Regression equations and related statistics describing the relation between specific conductance and total alkalinity and several dissolved constituents also were calculated. Typical water quality (based upon median values at individual stations) of physiographic sections and major rivers of Arkansas also is discussed. Discernible differences in water quality exist between sections and major rivers. The regression analysis indicated that the usefulness of specific conductance as a predictor of other water quality values is variable. The relation between specific conductance and the other property is not statistically significant (p>0.05) about 30% of the time. (USGS)

  1. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hiroto

    1995-02-07

    A reactor container of the present invention has a structure that the reactor container is entirely at the same temperature as that at the inlet of the reactor and, a hot pool is incorporated therein, and the reactor container has is entirely at the same temperature and has substantially uniform temperature follow-up property transiently. Namely, if the temperature at the inlet of the reactor core changes, the temperature of the entire reactor container changes following this change, but no great temperature gradient is caused in the axial direction and no great heat stresses due to axial temperature distribution is caused. Occurrence of thermal stresses caused by the axial temperature distribution can be suppressed to improve the reliability of the reactor container. In addition, since the laying of the reactor inlet pipelines over the inside of the reactor is eliminated, the reactor container is made compact and the heat shielding structures above the reactor and a protection structure of container walls are simplified. Further, secondary coolants are filled to the outside of the reactor container to simplify the shieldings. The combined effects described above can improve economical property and reliability. (N.H.).

  2. Fossil nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Maurette, M.

    1976-01-01

    The discussion of fossil nuclear reactors (the Oklo phenomenon) covers the earth science background, neutron-induced isotopes and reactor operating conditions, radiation-damage studies, and reactor modeling. In conclusion possible future studies are suggested and the significance of the data obtained in past studies is summarized. (JSR)

  3. Nuclear reactor repairing device

    International Nuclear Information System (INIS)

    Purpose: To enable free repairing of an arbitrary position in an LMFBR reactor. Constitution: A laser light emitted from a laser oscillator installed out of a nuclear reactor is guided into a portion to be repaired in the reactor by using a reflecting mirror, thereby welding or cutting it. The guidance of the laser out of the reactor into the reactor is performed by an extension tube depending into a through hole of a rotary plug, and the guidance of the laser light into a portion to be repaired is performed by the transmitting and condensing action of the reflecting mirror. (Kamimura, M.)

  4. Nuclear reactor physics

    CERN Document Server

    Stacey, Weston M

    2010-01-01

    Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developme

  5. Light water reactor safety

    CERN Document Server

    Pershagen, B

    2013-01-01

    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  6. Spinning fluids reactor

    Science.gov (United States)

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  7. Survey of Borreliae in ticks, canines, and white-tailed deer from Arkansas, U.S.A.

    Directory of Open Access Journals (Sweden)

    Fryxell Rebecca T

    2012-07-01

    Full Text Available Abstract Background In the Eastern and Upper Midwestern regions of North America, Ixodes scapularis (L. is the most abundant tick species encountered by humans and the primary vector of B. burgdorferi, whereas in the southeastern region Amblyomma americanum (Say is the most abundant tick species encountered by humans but cannot transmit B. burgdorferi. Surveys of Borreliae in ticks have been conducted in the southeastern United States and often these surveys identify B. lonestari as the primary Borrelia species, surveys have not included Arkansas ticks, canines, or white-tailed deer and B. lonestari is not considered pathogenic. The objective of this study was to identify Borrelia species within Arkansas by screening ticks (n = 2123, canines (n = 173, and white-tailed deer (n = 228 to determine the identity and locations of Borreliae endemic to Arkansas using PCR amplification of the flagellin (flaB gene. Methods Field collected ticks from canines and from hunter-killed white-tailed were identified to species and life stage. After which, ticks and their hosts were screened for the presence of Borrelia using PCR to amplify the flaB gene. A subset of the positive samples was confirmed with bidirectional sequencing. Results In total 53 (21.2% white-tailed deer, ten (6% canines, and 583 (27.5% Ixodid ticks (252 Ixodes scapularis, 161 A. americanum, 88 Rhipicephalus sanguineus, 50 Amblyomma maculatum, 19 Dermacentor variabilis, and 13 unidentified Amblyomma species produced a Borrelia flaB amplicon. Of the positive ticks, 324 (22.7% were collected from canines (151 A. americanum, 78 R. sanguineus, 43 I. scapularis, 26 A. maculatum, 18 D. variabilis, and 8 Amblyomma species and 259 (37.2% were collected from white-tailed deer (209 I. scapularis, 24 A. maculatum, 10 A. americanum, 10 R. sanguineus, 1 D. variabilis, and 5 Amblyomma species. None of the larvae were PCR positive. A majority of the flaB amplicons were homologous with B

  8. Reactor Vessel Surveillance Program for Advanced Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kyeong-Hoon; Kim, Tae-Wan; Lee, Gyu-Mahn; Kim, Jong-Wook; Park, Keun-Bae; Kim, Keung-Koo

    2008-10-15

    This report provides the design requirements of an integral type reactor vessel surveillance program for an integral type reactor in accordance with the requirements of Korean MEST (Ministry of Education, Science and Technology Development) Notice 2008-18. This report covers the requirements for the design of surveillance capsule assemblies including their test specimens, test block materials, handling tools, and monitors of the surveillance capsule neutron fluence and temperature. In addition, this report provides design requirements for the program for irradiation surveillance of reactor vessel materials, a layout of specimens and monitors in the surveillance capsule, procedures of installation and retrieval of the surveillance capsule assemblies, and the layout of the surveillance capsule assemblies in the reactor.

  9. Factors related to achievement in sophomore organic chemistry at the University of Arkansas

    Science.gov (United States)

    Lindsay, Harriet Arlene

    The purpose of this study was to identify the significant cognitive and non-cognitive variables that related to achievement in the first semester of organic chemistry at the University of Arkansas. Cognitive variables included second semester general chemistry grade, ACT composite score, ACT English, mathematics, reading, and science reasoning subscores, and spatial ability. Non-cognitive variables included anxiety, confidence, effectance motivation, and usefulness. Using a correlation research design, the individual relationships between organic chemistry achievement and each of the cognitive variables and non-cognitive variables were assessed. In addition, the relationships between organic chemistry achievement and combinations of these independent variables were explored. Finally, gender- and instructor-related differences in the relationships between organic chemistry achievement and the independent variables were investigated. The samples consisted of volunteers from the Fall 1999 and Fall 2000 sections of Organic Chemistry I at the University of Arkansas. All students in each section were asked to participate. Data for spatial ability and non-cognitive independent variables were collected using the Purdue Visualization of Rotations test and the modified Fennema-Sherman Attitude Scales. Data for other independent variables, including ACT scores and second semester general chemistry grades, were obtained from the Office of Institutional Research. The dependent variable, organic chemistry achievement, was measured by each student's accumulated points in the course and consisted of scores on quizzes and exams in the lecture section only. These totals were obtained from the lecture instructor at the end of each semester. Pearson correlation and stepwise multiple regression analyses were used to measure the relationships between organic chemistry achievement and the independent variables. Prior performance in chemistry as measured by second semester general

  10. Occurrence of organic wastewater and other contaminants in cave streams in northeastern Oklahoma and northwestern Arkansas

    Science.gov (United States)

    Bidwell, Joseph R.; Becker, C.; Hensley, S.; Stark, R.; Meyer, M.T.

    2010-01-01

    The prevalence of organic wastewater compounds in surface waters of the United States has been reported in a number of recent studies. In karstic areas, surface contaminants might be transported to groundwater and, ultimately, cave ecosystems, where they might impact resident biota. In this study, polar organic chemical integrative samplers (POCISs) and semipermeable membrane devices (SPMDs) were deployed in six caves and two surface-water sites located within the Ozark Plateau of northeastern Oklahoma and northwestern Arkansas in order to detect potential chemical contaminants in these systems. All caves sampled were known to contain populations of the threatened Ozark cavefish (Amblyopsis rosae). The surface-water site in Oklahoma was downstream from the outfall of a municipal wastewater treatment plant and a previous study indicated a hydrologic link between this stream and one of the caves. A total of 83 chemicals were detected in the POCIS and SPMD extracts from the surface-water and cave sites. Of these, 55 chemicals were detected in the caves. Regardless of the sampler used, more compounds were detected in the Oklahoma surface-water site than in the Arkansas site or the caves. The organic wastewater chemicals with the greatest mass measured in the sampler extracts included sterols (cholesterol and ??-sitosterol), plasticizers [diethylhexylphthalate and tris (2-butoxyethyl) phosphate], the herbicide bromacil, and the fragrance indole. Sampler extracts from most of the cave sites did not contain many wastewater contaminants, although extracts from samplers in the Oklahoma surfacewater site and the cave hydrologically linked to it had similar levels of diethylhexyphthalate and common detections of carbamazapine, sulfamethoxazole, benzophenone, N-diethyl-3-methylbenzamide (DEET), and octophenol monoethoxylate. Further evaluation of this system is warranted due to potential ongoing transport of wastewaterassociated chemicals into the cave. Halogenated organics

  11. Using Paid Radio Advertisements to Promote Physical Activity Among Arkansas Tweens

    Directory of Open Access Journals (Sweden)

    Appathurai Balamurugan, MD, MPH

    2005-11-01

    Full Text Available Introduction The level of physical activity among children is a growing concern. Evidence shows that many children aged 9 to 13 years (tweens do not participate in any organized physical activity during their nonschool hours, and some do not engage in any free-time physical activity. Physical inactivity is associated with a host of chronic diseases such as diabetes and cardiovascular disease. Paid media advertisements have been an effective method of promoting physical activity. Methods From March 10, 2003, through June 29, 2003, we aired paid radio advertisements in six major Arkansas metropolitan areas to promote physical activity among tweens. In September 2003, we surveyed 295 Arkansas tweens by telephone to assess their exposure to the advertisements and the impact of the advertisements on their intent to participate in physical activity. In the same telephone survey, we also asked questions about the respondents’ physical activity level. The data were weighted so that the results would be representative of the areas surveyed. The statistical analysis was performed using SPSS, version 11.5 (SPSS Inc, Chicago, Ill. Results Of the tweens surveyed, 56.4% (95% confidence interval [CI], 50.7%–62.1% reported hearing the radio advertisements. Of the tweens who heard the advertisement messages, 76.1% (95% CI, 69.4%–82.8% said the messages made them more likely to get involved in physical activity. Younger tweens (aged 9 and 10 years were less likely to have heard the advertisements than older tweens (aged 11 to 13 years. However, the advertisements were more likely to cause younger tweens to want to get involved in physical activity (odds ratio [OR] = 6.89, P = .003 than older tweens. Of the tweens surveyed, 74.9% (95% CI, 70.0%–79.8% reported that they were involved in nonschool-sponsored sports, and 45.3% (95% CI, 39.6%–51.0% were involved in school-sponsored sports. Conclusion Paid media advertisements may be an effective way to

  12. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  13. Multipurpose research reactors

    International Nuclear Information System (INIS)

    The international symposium on the utilization of multipurpose research reactors and related international co-operation was organized by the IAEA to provide for information exchange on current uses of research reactors and international co-operative projects. The symposium was attended by about 140 participants from 36 countries and two international organizations. There were 49 oral presentations of papers and 24 poster presentations. The presentations were divided into 7 sessions devoted to the following topics: neutron beam research and applications of neutron scattering (6 papers and 1 poster), reactor engineering (6 papers and 5 posters), irradiation testing of fuel and material for fission and fusion reactors (6 papers and 10 posters), research reactor utilization programmes (13 papers and 4 posters), neutron capture therapy (4 papers), neutron activation analysis (3 papers and 4 posters), application of small reactors in research and training (11 papers). A separate abstract was prepared for each of these papers. Refs, figs and tabs

  14. The UP modelling system for large scale hydrology: simulation of the Arkansas-Red River basin

    Directory of Open Access Journals (Sweden)

    C. G. Kilsby

    1999-01-01

    Full Text Available The UP (Upscaled Physically-based hydrological modelling system to the Arkansas-Red River basin (USA is designed for macro-scale simulations of land surface processes, and aims for a physical basis and, avoids the use of discharge records in the direct calibration of parameters. This is achieved in a two stage process: in the first stage parametrizations are derived from detailed modelling of selected representative small and then used in a second stage in which a simple distributed model is used to simulate the dynamic behaviour of the whole basin. The first stage of the process is described in a companion paper (Ewen et al., this issue, and the second stage of this process is described here. The model operated at an hourly time-step on 17-km grid squares for a two year simulation period, and represents all the important hydrological processes including regional aquifer recharge, groundwater discharge, infiltration- and saturation-excess runoff, evapotranspiration, snowmelt, overland and channel flow. Outputs from the model are discussed, and include river discharge at gauging stations and space-time fields of evaporation and soil moisture. Whilst the model efficiency assessed by comparison of simulated and observed discharge records is not as good as could be achieved with a model calibrated against discharge, there are considerable advantages in retaining a physical basis in applications to ungauged river basins and assessments of impacts of land use or climate change.

  15. Predictors of Substance Abuse Treatment Entry Among Rural Illicit Stimulant Users in Ohio, Arkansas, and Kentucky

    Science.gov (United States)

    Carlson, Robert G.; Sexton, Rocky; Wang, Jichuan; Falck, Russel; Leukefeld, Carl G.; Booth, Brenda M.

    2010-01-01

    Illicit drug use in the rural United States is increasingly common, yet little is known about drug users’ treatment-seeking behaviors. This study identifies predictors of substance abuse treatment entry over 24 months among 710 illicit stimulant users in rural areas of Ohio, Arkansas, and Kentucky. Active users of powdered cocaine, crack cocaine, and/or methamphetamine (MA) were recruited using respondent-driven sampling. Participants completed structured interviews at baseline and follow-up questionnaires every 6 months for 24 months. Data were analyzed using the Cox proportional hazards model. The paper is informed by the Anderson-Newman Model. Overall, 18.7% of the sample entered treatment. Ohio or Kentucky residence, perceived need for substance abuse treatment, higher ASI legal problem composite scores, prior substance abuse treatment, and tranquilizer use were positively associated with treatment entry. Non-daily crack cocaine users and marijuana users were less likely to enter treatment. The findings can help inform rural substance abuse treatment program development and outreach. PMID:20391264

  16. Digital model of the Bayou Bartholomew alluvial aquifer stream system, Arkansas

    Science.gov (United States)

    Reed, J.E.; Broom, Matthew E.

    1979-01-01

    A digital model of the Bayou Bartholomew aquifer-stream system in Arkansas was calibrated for the purpose of predicting hydrologic responses to stresses of water development. The simulated-time span for model calibration was from 1953 to 1970, during which time the system was stressed largely by ground- and surface-water diversions for rice irrigation. The model was calibrated by comparing groundwater-level and streamflow data with model-derived groundwater levels and streamflow. In the calibrated model, the ratio of model-derived to observed streamflows for 17 subbasins averaged 1.1; the ratios among the subbasins ranged from 0.8 to 1.6. The average deviation of the differences between model-derived and observed groundwater levels at 47 nodes was 0.2; the average among the nodes ranged from -2.3 to 10.4. The average standard deviation of the differences between the model-derived and observed groundwater levels was 3.5; the average among the nodes ranged from 0.4 to 10.5. The model will provide projections of changes in the potentiometric surface resulting from (1) changes in the rate or distribution of groundwater pumpage or (2) changes in the stage of streams and reservoirs. The model will provide only approximate projections of the streamflow. (USGS)

  17. Bacteria and Turbidity Survey for Blue Mountain Lake, Arkansas, Spring and Summer, 1994

    Science.gov (United States)

    Lasker, A. Dwight

    1995-01-01

    Introduction Blue Mountain Lake darn is located at river mile 74.4 on the Petit Jean River in Logan and Yell Counties in west-central Arkansas (fig. 1). Drainage area above the darn is 488 square miles. Blue Mountain Lake is located between two national forests-the Ozark National Forest and the Ouachita National Forest. The primary purpose for Blue Mountain Lake is flood control, but the lake is used for a variety of recreational purposes. The U.S. Geological Survey (USGS) in cooperation with the U.s. Army Corps of Engineers, Little Rock District, conducted a bacterial and turbidity study of the Blue Mountain Lake Basin during the spring and suri1mer 1994. Samples were collected weekly at 11 locations within the lake basin from May through September 1994. Eight sampling sites were located on tributaries to the lake and three sampling sites were located on the lake with one of the sites located at a swim beach (fig. 2; table 1).

  18. Size distribution of planktonic autotrophy and microheterotrophy in DeGray Reservoir, Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Kimmel, B.L.; Groeger, A.W.

    1983-01-01

    Naturally occurring assemblages of phytoplankton and bacterioplankton were radiolabelled with sodium /sup 14/C-bicarbonate and sodium /sup 3/H-acetate and size fractionated to determine the size structure of planktonic autotrophy and microheterotrophy in DeGray Reservoir, an oligotrophic impoundment of the Caddo River in south-central Arkansas. Size distributions of autotrophy and microheterotrophy were remarkably uniform seasonally, vertically within the water column, and along the longitudinal axis of the reservoir despite significant changes in environmental conditions. Planktonic autotrophy was dominated by small algal cells with usually >50% of the photosynthetic carbon uptake accounted for by organisms <8.0 ..mu..m. Microheterotrophic activity in the 0.2- to 1.0-..mu..m size fraction, presumably associated with free-living bacterioplankton not attached to suspended particles, usually accounted for >75% of the planktonic microheterotrophy. Longitudinal patterns in autotrophic and microheterotrophic activities associated with >3-..mu..m and >1-..mu..m size fractions, respectively, suggest an uplake to downlake shift from riverine to lacustrine environmental influences within the reservoir. 83 references, 7 figures.

  19. Duplex-like structures in submarine fan channels, Ouachita Mountains, Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Shanmugam, G.; Moiola, R.J.; Sales, J.K.

    1988-03-01

    Submarine fan channel sequences of the Jackfork Formation (Lower Pennsylvanian) at DeGray Dam section in the Ouachita Mountains, Arkansas, contain discrete units (10-75 cm thick) with moderately dipping (25/sup 0/-40/sup 0/), sigmoidal imbricate slices. Adjacent units with opposing imbricate slices are common. The sigmoidal structures are similar in geometry to a tectonic feature known as a duplex. A tectonic origin of sigmoidal structures, however, seems unlikely because opposing directions of imbrication in adjacent units would require an unrealistic tectonic movement history for the area. The authors propose that the Jackfork sigmoidal structures were formed by a process kinematically similar to that responsible for generating duplex structures. Unlike tectonic duplexes, however, the sigmoidal structures were formed by soft-sediment deformation of sand and mud layers as high-energy sediment gravity flows glided over these layers. Sediment gravity flows, responsible for forming the sigmoidal deformation, were probably generated by slumping of adjacent channel walls. Dip direction of sigmoidal slices is perpendicular to channel axes. Thus, recognition of sigmoidal deformation structures may be useful in inferring the trend of channels in ancient submarine fan complexes.

  20. Atmospheric Contributors to Heavy Rainfall Events in the Arkansas-Red River Basin

    Directory of Open Access Journals (Sweden)

    Taylor A. McCorkle

    2016-01-01

    Full Text Available This study analyzed the top 1% 24-hour rainfall events from 1994 to 2013 at eight climatological sites that represent the east to west precipitation gradient across the Arkansas-Red River Basin in North America. A total of 131 cases were identified and subsequently classified on the synoptic-scale, mesoscale, and local-scale to compile a climatological analysis of these extreme, heavy rainfall events based on atmospheric forcings. For each location, the prominent midtropospheric pattern, mesoscale feature, and predetermined thermodynamic variables were used to classify each 1% rainfall event. Individual events were then compared with other cases throughout the basin. The most profound results were that the magnitudes of the thermodynamic variables such as convective available potential energy and precipitable water values were poor predictors of the amount of rainfall produced in these extreme events. Further, the mesoscale forcings had more of an impact during the warm season and for the westernmost locations, whereas synoptic forcings were extremely prevalent during the cold season at the easternmost locations in the basin. The implications of this research are aimed at improving the forecasting of heavy precipitation at individual weather forecasts offices within the basin through the identified patterns at various scales.

  1. Disposal of chemical agents and munitions stored at Pine Bluff Arsenal, Pine Bluff, Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Ensminger, J.T.; Hillsman, E.L.; Johnson, R.D.; Morrisey, J.A.; Staub, W.P.; Boston, C.R.; Hunsaker, D.B.; Leibsch, E.; Rickert, L.W.; Tolbert, V.R.; Zimmerman, G.P.

    1991-09-01

    The Pine Bluff Arsenal (PBA) near Pine Bluff, Arkansas, is one of eight continental United States (CONUS) Army installations where lethal unitary chemical agents and munitions are stored and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at PBA consists of approximately 12%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts). The purpose of this report is to examine the proposed implementation of on-site disposal at PBA in light of more recent and more detailed data than those on which the FPEIS is based. New population data were used to compute fatalities using the same computation methods and values for all other parameters as in the FPEIS. Results indicate that all alternatives are indistinguishable when the potential health impacts to the PBA community are considered. However, risks from on-site disposal are in all cases equal to or less than risks from other alternatives. Furthermore, no unique resources with the potential to prevent or delay implementation of on-site disposal at PBA have been identified.

  2. Cadmium Accumulation in Periphyton from an Abandoned Mining District in the Buffalo National River, Arkansas.

    Science.gov (United States)

    McCauley, Jacob R; Bouldin, Jennifer L

    2016-06-01

    The Rush Mining District along the Buffalo River in Arkansas has a significant history of zinc and lead mining operations. The tails and spoils of these operations deposit heavy amounts of raw ore into streams. One element commonly found in the earth's crust that becomes a minor constituent of the deposition is cadmium. Periphyton samples from Rush Creek and Clabber Creek, two creeks within the Rush Mining District were measured for cadmium as well as two creeks with no history of mining, Spring Creek and Water Creek. Periphyton samples from Rush and Clabber Creek contained mean cadmium concentrations of 436.6 ± 67.3 and 93.38 ± 8.67 µg/kg, respectively. Spring Creek and Water Creek had a mean cadmium concentration of 40.49 ± 3.40 and 41.78 ± 3.99 µg/kg within periphyton. The results indicate increased metal concentrations in algal communities from mined areas. As periphyton is the base of the aquatic food chain, it acts as a conduit for movement of cadmium in the food web. PMID:27130541

  3. Detection of Lead (Pb) in Three Environmental Matrices of the Cache River Watershed, Arkansas.

    Science.gov (United States)

    Kilmer, Mary K; Bouldin, Jennifer L

    2016-06-01

    Water bodies contaminated with lead (Pb) represent a considerable threat to both human and environmental health. The Cache River, located in northeastern Arkansas has been listed as impaired on the 303(d) list due to Pb contamination. However, historical data for the watershed is limited in both sampled waterways and analyses performed. This study measures concentrations of Pb in three environmental matrices of the Cache River Watershed; dissolved in the water column, total Pb (dissolved + particulate), and sediment-bound Pb. A variety of waterways were sampled including main channel and tributary sites. Frequency of detection and mean concentrations were compared to values for the entire Lower Mississippi Watershed. In general, no significant differences were found for the CRW when compared to the LMRW, with the exception of total Pb which was detected more frequently but at lower concentrations in the CRW than in the LMRW, and sediment Pb, which was detected at a significantly lower frequency in the CRW than the LMRW. PMID:26858084

  4. Hard lives, God's help, and struggling through: caregiving in Arkansas Delta.

    Science.gov (United States)

    Gerdner, Linda A; Tripp-Reimer, Toni; Simpson, Helen C

    2007-12-01

    The purpose of this ethnographic study was to describe the experience of African American adults providing in-home care for a family member with chronic confusion living in the Arkansas Delta. We conducted this study over fourteen months in two rural Delta counties using participant observation and in-depth interviews. The majority of caregivers were adult daughters. Nearly half attributed chronic confusion to a difficult life and emotional stress or "worry;" a third believed it to be a natural component of "old age." Caregivers tended to view their work as an expression of love and devotion that was accompanied by emotional stress and personal sacrifice. While just under half of the caregivers had no other family members willing or available to assist with the physical care of the elder, the majority were able to turn to family members for emotional support. Further they identified strong religious beliefs as the primary force that sustained them in the caregiving role. The centrality of spirituality, faith/religion was noted in nearly all aspects of life. Faith in God was seen as continuing to be an important aspect of the care recipients' lives as well. Recipients' spiritual needs were addressed by accompanying the care recipient to church services and reading Bible passages to them on a regular basis. Selective community services (i.e., adult day care, home health services) were used that supported efforts at maintaining the family caregiver role. Findings are discussed within the context of historical and sociopolitical factors of the geographic region.

  5. Description of Survey Data Regarding the Chemical Repackaging Plant Accident West Helena, Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, J.H.; Vogt, B.M.

    1999-03-01

    Shortly after 1:00 p.m. on Thursday, May 8, 1997, clouds of foul-smelling smoke began pouring from an herbicide and pesticide packaging plant in West Helena, Arkansas. An alert was sounded, employees evacuated, and the West Helena fire department was called. As three firefighters prepared to enter the plant, the chemical compounds exploded, collapsing a solid concrete block wall, and killing all three firefighters. As the odorous smoky cloud drifted away from the plant, authorities ordered residents in a 2-mile area downwind of the plant to evacuate and those in the 2- to 3-mile zone to shelter in place. This study examines and compares the responses to a mail survey of those ordered to evacuate and those told to shelter in place. Among the variables examined are compliance with official orders and perceived warnings, threat perception, time and source of first warning, response times, and behavior characteristics for both populations. The findings indicate that 90% of those that were told to evacuate did so but only 27% of those told to shelter-in-place did so, with 68% opting to evacuate instead. The implications of these findings for emergency managers is that people will likely choose to evacuate when both warnings to evacuate and warnings to shelter are issued to residents in close proximity to each other. The findings on warning times closely resemble other findings from evacuations when chemical accidents occur and route notification is used for warning residents.

  6. Reactor BR2

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2000-07-01

    The BR2 reactor is still SCK-CEN's most important nuclear facility. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. Various aspects concerning the operation of the BR2 Reactor, the utilisation of the CALLISTO loop and the irradiation programme, the BR2 R and D programme and the production of isotopes and of NTD-silicon are discussed. Progress and achievements in 1999 are reported.

  7. The Integral Fast Reactor

    International Nuclear Information System (INIS)

    The Integral Fast Reactor (IFR) is an innovative liquid metal reactor concept being developed at Argonne National Laboratory. It seeks to specifically exploit the inherent properties of liquid metal cooling and metallic fuel in a way that leads to substantial improvements in the characteristics of the complete reactor system. This paper describes the key features and potential advantages of the IFR concept, with emphasis on its safety characteristics. 3 refs., 4 figs., 1 tab

  8. Reactor Engineering Division annual report

    International Nuclear Information System (INIS)

    Research and development activities in the Division of Reactor Engineering in fiscal 1981 are described. The work of the Division is closely related to development of multipurpose Very High Temperature Gas Cooled Reactor and fusion reactor, and development of Liquid Metal Fast Breeder Reactor carried out by Power Reactor and Nuclear Fuel Development Corporation. Contents of the report are achievements in fields such as nuclear data and group constants, theoretical method and code development, integral experiment and analysis, shielding, reactor and nuclear instrumentation, reactor control and diagnosis, and fusion reactor technology, and activities of the Committee on Reactor Physics. (author)

  9. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Mitsuru

    1997-04-04

    An LMFBR type reactor comprises a plurality of reactor cores in a reactor container. Namely, a plurality of pot containing vessels are disposed in the reactor vessel and a plurality of reactor cores are formed in a state where an integrated-type fuel assembly is each inserted to a pot, and a coolant pipeline is connected to each of the pot containing-vessel to cool the reactor core respectively. When fuels are exchanged, the integrated-type fuel assembly is taken out together with the pot from the reactor vessel in a state where the integrated-type fuel assembly is immersed in the coolants in the pot as it is. Accordingly, coolants are supplied to each of the pot containing-vessel connected with the coolant pipeline and circulate while cooling the integrated-type fuel assembly for every pot. Then, when the fuels are exchanged, the integrated type fuel assembly is taken out to the outside of the reactor together with the pot by taking up the pot from the pot-containing vessel. Then, neutron economy is improved to thereby improve reactor power and the breeding ratio. (N.H.)

  10. One piece reactor removal

    International Nuclear Information System (INIS)

    Japan Research Reactor No.3 (JRR-3) was the first reactor consisting of 'Japanese-made' components alone except for fuel and heavy water. After reaching its initial critical state in September 1962, JRR-3 had been in operation for 21 years until March 1983. It was decided that the reactor be removed en-bloc in view of the work schedule, cost and management of the reactor following the removal. In the special method developed jointly by the Japanese Atomic Energy Research Institute and Shimizu Construction Co., Ltd., the reactor main unit was cut off from the building by continuous core boring, with its major components bound in the block with biological shield material (heavy concrete), and then conveyed and stored in a large waste store building constructed near the reactor building. Major work processes described in this report include the cutting off, lifting, horizontal conveyance and lowering of the reactor main unit. The removal of the JRR-3 reactor main unit was successfully carried out safely and quickly by the en-block removal method with radiation exposure dose of the workers being kept at a minimum. Thus the high performance of the en-bloc removal method was demonstrated and, in addition, valuable knowhow and other data were obtained from the work. (Nogami, K.)

  11. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2001-04-01

    The activities of the Reactor Materials Research Department of the Belgian Nuclear Research Centre SCK-CEN in 2000 are summarised. The programmes within the department are focussed on studies concerning (1) fusion, in particular mechanical testing; (2) Irradiation Assisted Stress Corrosion Cracking (IASCC); (3) nuclear fuel; and (4) Reactor Pressure Vessel Steel (RPVS)

  12. Light water reactor program

    Energy Technology Data Exchange (ETDEWEB)

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  13. Research reactor DHRUVA

    International Nuclear Information System (INIS)

    DHRUVA, a 100 MWt research reactor located at the Bhabha Atomic Research Centre, Bombay, attained first criticality during August, 1985. The reactor is fuelled with natural uranium and is cooled, moderated and reflected by heavy water. Maximum thermal neutron flux obtained in the reactor is 1.8 X 1014 n/cm2/sec. Some of the salient design features of the reactor are discussed in this paper. Some important features of the reactor coolant system, regulation and protection systems and experimental facilities are presented. A short account of the engineered safety features is provided. Some of the problems that were faced during commissioning and the initial phase of power operation are also dealt upon

  14. TRIGA research reactors

    International Nuclear Information System (INIS)

    TRIGA (Training, Research, Isotope production, General-Atomic) has become the most used research reactor in the world with 65 units operating in 24 countries. The original patent for TRIGA reactors was registered in 1958. The success of this reactor is due to its inherent level of safety that results from a prompt negative temperature coefficient. Most of the neutron moderation occurs in the nuclear fuel (UZrH) because of the presence of hydrogen atoms, so in case of an increase of fuel temperature, the neutron spectrum becomes harder and neutrons are less likely to fission uranium nuclei and as a consequence the power released decreases. This inherent level of safety has made this reactor fit for training tool in university laboratories. Some recent versions of TRIGA reactors have been designed for medicine and industrial isotope production, for neutron therapy of cancers and for providing a neutron source. (A.C.)

  15. Mirror reactor surface study

    International Nuclear Information System (INIS)

    A general survey is presented of surface-related phenomena associated with the following mirror reactor elements: plasma first wall, ion sources, neutral beams, director converters, vacuum systems, and plasma diagnostics. A discussion of surface phenomena in possible abnormal reactor operation is included. Several studies which appear to merit immediate attention and which are essential to the development of mirror reactors are abstracted from the list of recommended areas for surface work. The appendix contains a discussion of the fundamentals of particle/surface interactions. The interactions surveyed are backscattering, thermal desorption, sputtering, diffusion, particle ranges in solids, and surface spectroscopic methods. A bibliography lists references in a number of categories pertinent to mirror reactors. Several complete published and unpublished reports on surface aspects of current mirror plasma experiments and reactor developments are also included

  16. Iris reactor conceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Carelli, M.D.; Conway, L.E.; Petrovic, B.; Paramonov, D.V. [Westinghouse Electric Comp., Pittsburgh, PA (United States); Galvin, M.; Todreas, N.E. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Lombardi, C.V.; Maldari, F.; Ricotti, M.E. [Politecnico di Milano, Milan (Italy); Cinotti, L. [Ansaldo SpA, Genoa (Italy)

    2001-07-01

    IRIS (International Reactor Innovative and Secure) is a modular, integral, light water cooled, low-to-medium power (100-350 MWe) reactor which addresses the requirements defined by the US DOE for Generation IV reactors, i.e., proliferation resistance, enhanced safety, improved economics and fuel cycle sustainability. It relies on the proven technology of light water reactors and features innovative engineering, but it does not require new technology development. This paper discusses the current reference IRIS design, which features a 1000 MWt thermal core with proven 5%-enriched uranium oxide fuel and five-year long straight burn fuel cycle, integral reactor vessel housing helical tube steam generators and immersed spool pumps. Other major contributors to the high level of safety and economic attractiveness are the safety by design and optimized maintenance approaches, which allow elimination of some classes of accidents, lower capital cost, long operating cycle, and high capacity factors. (author)

  17. Status of French reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A. [Commissariat a l`Energie Atomique, Saclay (France)

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  18. Compact torsatron reactors

    International Nuclear Information System (INIS)

    Low-aspect-ratio torsatron configurations could lead to compact stellarator reactors with R0 = 8--11m, roughly one-half to one-third the size of more conventional stellarator reactor designs. Minimum-size torsatron reactors are found using various assumptions. Their size is relatively insensitive to the choice of the conductor parameters and depends mostly on geometrical constraints. The smallest size is obtained by eliminating the tritium breeding blanket under the helical winding on the inboard side and by reducing the radial depth of the superconducting coil. Engineering design issues and reactor performance are examined for three examples to illustrate the feasibility of this approach for compact reactors and for a medium-size (R0 ≅ 4 m,/bar a/ /approx lt/ 1 m) copper-coil ignition experiment. 26 refs., 11 figs., 7 tabs

  19. Nuclear reactor design

    CERN Document Server

    2014-01-01

    This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.

  20. Aerial gamma ray and magnetic survey: Mississippi and Florida airborne survey, Fort Smith quadrangle, Oklahoma, and Arkansas. Final report

    International Nuclear Information System (INIS)

    The Fort Smith quadrangle in western Arkansas and eastern Oklahoma overlies thick Paleozoic sediments of the Arkoma Basin. These Paleozoics dominate surface exposure except where covered by Quaternary Alluvial materials. Examination of available literature shows no known uranium deposits (or occurrences) within the quadrangle. Seventy-five groups of uranium samples were defined as anomalies and are discussed briefly. None were considered significant, and most appeared to be of cultural origin. Magnetic data show character that suggest structural and/or lithologic complexity, but imply relatively deep-seated sources

  1. Reactor Engineering Division annual report

    International Nuclear Information System (INIS)

    Research activities in the Division of Reactor Engineering in fiscal 1977 are described. Works of the Division are development of multi-purpose Very High Temperature Gas Cooled Reactor, fusion reactor engineering, and development of Liquid Metal Fast Breeder Reactor for Power Reactor and Nuclear Fuel Development Corporation. Contents of the report are nuclear data and group constants, theoretical method and code development, integral experiment and analysis, shielding, heat transfer and fluid dynamics, reactor and nuclear instrumentation, dynamics analysis and control method development, fusion reactor technology, and Committee on Reactor Physics. (Author)

  2. Reactor Engineering Department annual report

    International Nuclear Information System (INIS)

    Research and development activities in the Department of Reactor Engineering in fiscal 1983 are described. The work of the Department is closely related to development of multipurpose Very High Temperature Gas Cooled Reactor and Fusion Reactor, and development of Liquid Metal Fast Breeder Reactor carried out by Power Reactor and Nuclear Fuel Development Corporation. Contents of the report are achievements in fields such as nuclear data and group constants, theoretical method and code development, integral experiment and analysis, fusion neutronics, shielding, reactor and nuclear instrumentation, reactor control and diagnosis, and safeguards technology, and activities of the Committee on Reactor Physics. (author)

  3. Reactor Engineering Division annual report

    International Nuclear Information System (INIS)

    Research activities conducted in Reactor Engineering Division in fiscal 1975 are summarized in this report. Works in the division are closely related to the development of multi-purpose High-temperature Gas Cooled Reactor, the development of Liquid Metal Fast Breeder Reactor by Power Reactor and Nuclear Fuel Development Corporation, and engineering research of thermonuclear fusion reactor. Many achievements are described concerning nuclear data and group constants, theoretical method and code development, integral experiment and analysis, shielding, heat transfer and fluid dynamics, reactor and nuclear instrumentation, dynamics analysis and control method development, fusion reactor technology and activities of the Committee on Reactor Physics. (auth.)

  4. Geomorphic Characterization of the Middle Fork Saline River: Garland, Perry, and Saline Counties, Arkansas

    Science.gov (United States)

    Pugh, Aaron L.; Garday, Thomas J.; Redman, Ronald

    2008-01-01

    This report was prepared to help address concerns raised by local residents, State, and Federal agencies about the current geomorphic conditions of the Middle Fork Saline River. Over the past 30 years the Middle Fork Saline River Basin has experienced a marked increase in urbanization. The report summarizes the Middle Fork?s current (2003) channel characteristics at nine stream reaches in the upper 91 square miles of the basin. Assessments at each study reach included comparing measured stream geometry dimensions (cross-sectional area, top width, and mean depth) at bankfull stage to regional hydraulic geometry curves for the Ouachita Mountains Physiographic Province of Arkansas and Oklahoma, evaluations of streambed materials and sinuosity, and classification of individual stream reach types. When compared to the Ouachita Mountains? regional hydraulic geometry curves for natural, stable, stream reaches, five of the nine study reaches had slightly smaller crosssectional areas, longer top widths, and shallower depths. Streambed material analysis indicates that the Middle Fork is a bedrock influenced, gravel dominated stream with lesser amounts of sand and cobbles. Slight increases in sinuosity from 1992 to 2002 at seven of the nine study reaches indicate a slight decrease in stream channel slope. Analyses of the Middle Fork?s hydraulic geometry and sinuosity indicate that the Middle Fork is currently overly wide and shallow, but is slowly adjusting towards a deeper, narrower hydraulic geometry. Using the Rosgen system of channel classification, the two upstream study reaches classified as B4c/1 stream types; which were moderately entrenched, riffle dominated channels, with infrequently spaced pools. The downstream seven study reaches classified as C4/1 stream types; which were slightly entrenched, meandering, gravel-dominated, riffle/ pool channels with well developed flood plains. Analyses of stream reach types suggest that the downstream reaches of the Middle Fork

  5. Morphodynamics of neck cutoffs on elongate meander loops, White River, Arkansas, USA

    Science.gov (United States)

    Konsoer, K. M.

    2015-12-01

    Meander cutoff and oxbow lake formation are essential components of alluvial architecture and riverine habitat of meandering river floodplains. Yet, despite their ubiquitous presence within active floodplains, the detailed processes involved in the initiation of cutoffs and oxbow lakes remain incompletely understood, primarily due to the intermittent nature of such events. Furthermore, conceptual models of meander cutoff and oxbow lake formation have been primarily developed for chute cutoffs and relatively simple planform configurations. Less attention has been given to neck cutoff dynamics occurring on highly sinuous meandering rivers with complex planform morphology. During the formation of a neck cutoff on a compound elongate loop, the upstream and downstream limbs can become oriented roughly subparallel with flow in opposite directions separated by a narrow meander neck. Immediately following cutoff of this thin neck, flow from the upstream limb is sharply redirected into the downstream limb over a short distance. These conditions of tight bend flow should become more pronounced as the ratio of radius of curvature to channel width become smaller, leading to complex patterns of three-dimensional velocities that have implications for the evolution of the cutoff channel and the transformation of the abandoned bend into an oxbow lake. This paper investigates the process dynamics of neck cutoff and oxbow lake formation using detailed field measurements of three-dimensional flow velocities, channel bed topography and geotechnical analysis of the banks and floodplains from three neck cutoffs along the White River, Arkansas (USA), each representing a different stage in the morphologic evolution from cutoff to oxbow lake. Results from this study suggests that the planform geometry of neck cutoff on an elongate meander loop can influence the spatial pattern of sediment deposition within the abandoned loop leading to increased hydrologic connectivity to the main channel

  6. Reactor performance calculations for water reactors

    International Nuclear Information System (INIS)

    The principles of nuclear, thermal and hydraulic performance calculations for water cooled reactors are discussed. The principles are illustrated by describing their implementation in the UKAEA PATRIARCH scheme of computer codes. This material was originally delivered as a course of lectures at the Technical University of Helsinki in Summer of 1969.

  7. Safety of research reactors

    International Nuclear Information System (INIS)

    The number of research reactors that have been constructed worldwide for civilian applications is about 651. Of the reactors constructed, 284 are currently in operation, 258 are shut down and 109 have been decommissioned. More than half of all operating research reactors worldwide are over thirty years old. During this long period of time national priorities have changed. Facility ageing, if not properly managed, has a natural degrading effect. Many research reactors face concerns with the obsolescence of equipment, lack of experimental programmes, lack of funding for operation and maintenance and loss of expertise through ageing and retirement of the staff. Other reactors of the same vintage maintain effective ageing management programmes, conduct active research programmes, develop and retain high calibre personnel and make important contributions to society. Many countries that operate research reactors neither operate nor plan to operate power reactors. In most of these countries there is a tendency not to create a formal regulatory body. A safety committee, not always independent of the operating organization, may be responsible for regulatory oversight. Even in countries with nuclear power plants, a regulatory regime differing from the one used for the power plants may exist. Concern is therefore focused on one tail of a continuous spectrum of operational performance. The IAEA has been sending missions to review the safety of research reactors in Member States since 1972. Some of the reviews have been conducted pursuant to the IAEA' functions and responsibilities regarding research reactors that are operated within the framework of Project and Supply Agreements between Member States and the IAEA. Other reviews have been conducted upon request. All these reviews are conducted following procedures for Integrated Safety Assessment of Research Reactors (INSARR) missions. The prime objective of these missions has been to conduct a comprehensive operational safety

  8. Reactor Engineering Department annual report

    International Nuclear Information System (INIS)

    This report summarizes the research and development activities in the Department of Reactor Engineering during the fiscal year of 1992 (April 1, 1992-March 31, 1993). The major Department's programs promoted in the year are the assessment of the high conversion light water reactor, the design activities of advanced reactor system and development of a high energy proton linear accelerator for the engineering applications including TRU incineration. Other major tasks of the Department are various basic researches on the nuclear data and group constants, the developments of theoretical methods and codes, the reactor physics experiments and their analyses, fusion neutronics, radiation shielding, reactor instrumentation, reactor control/diagnosis, thermohydraulics and technology developments related to the reactor physics facilities. The cooperative works to JAERI's major projects such as the high temperature gas cooled reactor or the fusion reactor and to PNC's fast reactor project were also progressed. The activities of the Research Committee on Reactor Physics are also summarized. (author)

  9. Reactor engineering department annual report

    International Nuclear Information System (INIS)

    This report summarizes the research and development activities in the Department of Reactor Engineering during the fiscal year of 1989 (April 1, 1989 - March 31, 1990). One of major Department's programs is the assessment of the high conversion light water reactor and the design activities of advanced reactor system. Development of a high energy proton linear accelerator for the nuclear engineering including is also TRU incineration promoted. Other major tasks of the Department are various basic researches on nuclear data and group constants, theoretical methods and code development, on reactor physics experiments and analyses, fusion neutronics, radiation shielding, reactor instrumentation, reactor control/diagnosis, thermohydraulics, technology assessment of nuclear energy and technology developments related to the reactor physics facilities. The cooperative works to JAERI's major projects such as the high temperature gas cooled reactor or the fusion reactor and to PNC's fast reactor project also progressed. The activities of the Research Committee on Reactor Physics are also summarized. (author)

  10. Slurry reactor design studies

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. (Bechtel Group, Inc., San Francisco, CA (USA)); Akgerman, A. (Texas A and M Univ., College Station, TX (USA)); Smith, J.M. (California Univ., Davis, CA (USA))

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  11. Test reactor technology

    International Nuclear Information System (INIS)

    The Reactor Development Program created a need for engineering testing of fuels and materials. The Engineering Test Reactors were developed around the world in response to this demand. The design of the test reactors proved to be different from that of power reactors, carrying the fuel elements closer to the threshold of failure, requiring more responsive instrumentation, more rapid control element action, and inherent self-limiting behavior under accident conditions. The design of the experimental facilities to exploit these reactors evolved a new, specialized, branch of engineering, requiring a very high-lvel scientific and engineering team, established a meticulous concern with reliability, the provision for recovery from their own failures, and detailed attention to possible interactions with the test reactors. This paper presents this technology commencing with the Materials Testing Reactor (MTR) through the Fast Flux Test Facility, some of the unique experimental facilities developed to exploit them, but discusses only cursorily the experiments performed, since sample preparation and sample analyses were, and to some extent still are, either classified or proprietary. The Nuclear Engineering literature is filled with this information

  12. Fast Breeder Reactor studies

    International Nuclear Information System (INIS)

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts

  13. Fast Breeder Reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  14. Licensed operating reactors

    International Nuclear Information System (INIS)

    The Operating Units Status Report --- Licensed Operating Reactors provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management from the Headquarters staff on NRC's Office of Enforcement (OE), from NRC's Regional Offices, and from utilities. The three sections of the report are: monthly highlights and statistics for commercial operating units, and errata from previously reported data; a compilation of detailed information on each unit, provided by NRC's Regional Offices, OE Headquarters and the utilities; and an appendix for miscellaneous information such as spent fuel storage capability, reactor-years of experience and non- power reactors in the US

  15. nuclear reactor design calculations

    International Nuclear Information System (INIS)

    In this work , the sensitivity of different reactor calculation methods, and the effect of different assumptions and/or approximation are evaluated . A new concept named error map is developed to determine the relative importance of different factors affecting the accuracy of calculations. To achieve this goal a generalized, multigroup, multi dimension code UAR-DEPLETION is developed to calculate the spatial distribution of neutron flux, effective multiplication factor and the spatial composition of a reactor core for a period of time and for specified reactor operating conditions. The code also investigates the fuel management strategies and policies for the entire fuel cycle to meet the constraints of material and operating limitations

  16. Course on reactor physics

    International Nuclear Information System (INIS)

    In Germany only few students graduate in nuclear technology, therefore the NPP operating companies are forced to develop their own education and training concepts. AREVA NP has started together with the Technical University of Dresden a one-week course ''reactor physics'' that includes the know-how of the nuclear power plant construction company. The Technical University of Dresden has the training reactor AKR-2 that is retrofitted by modern digital instrumentation and control technology that allows the practical training of reactor control.

  17. PWR type reactor

    International Nuclear Information System (INIS)

    From a PWR with a primary circuit, consisting of a reactor pressure vessel, a steam generator and a reactor coolant pump, hot coolant is removed by means of an auxiliary system containing h.p. pumps for feeding water into the primary circuit and being connected with a pipe, originating at the upper part, which has got at least one isolating value. This is done by opening an outlet in a part of the auxiliary system that has got a lower pressure than the reactor vessel. Preferably a water jet pump is used for mixing with the water of the auxiliary system. (orig.)

  18. Microfluidic electrochemical reactors

    Science.gov (United States)

    Nuzzo, Ralph G.; Mitrovski, Svetlana M.

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  19. National Uranium Resource Evaluation Program. Data report: Arkansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas. Hydrogeochemical and stream sediment reconnaissance

    International Nuclear Information System (INIS)

    This report presents the results of ground water, stream water, and stream sediment reconnaissance in Arkansas, Louisiana, Mississippi, Missouri, Oklahoma, and Texas. The following samples were collected: Arkansas-3292 stream sediments, 5121 ground waters, 1711 stream waters; Louisiana-1017 stream sediments, 0 ground waters, 0 stream waters; Misissippi-0 stream sediments, 814 ground waters, 0 stream waters; Missouri-2162 stream sediments, 3423 ground waters 1340 stream waters; Oklahoma-2493 stream sediments, 2751 ground waters, 375 stream waters; and Texas-279 stream sediments, 0 ground waters, 0 stream waters. Neutron activation analyses are given for U, Br, Cl, F, Mn, Na, Al, V, and Dy in ground water and stream water, and for U, Th, Hf, Ce, Fe, Mn, Na, Sc, Ti, V, Al, Dy, Eu, La, Sm, Yb, and Lu in sediments. The results of mass spectroscopic analysis for He are given for 563 ground water sites in Mississippi. Field measurements and observations are reported for each site. Oak Ridge National Laboratory analyzed sediment samples which were not analyzed by Savannah River Laboratory neutron activation

  20. The Impact Of State Policies On ACA Applications And Enrollment Among Low-Income Adults In Arkansas, Kentucky, And Texas.

    Science.gov (United States)

    Sommers, Benjamin D; Maylone, Bethany; Nguyen, Kevin H; Blendon, Robert J; Epstein, Arnold M

    2015-06-01

    States are taking variable approaches to the Affordable Care Act (ACA) Medicaid expansion, Marketplace design, enrollment outreach, and application assistance. We surveyed nearly 3,000 low-income adults in late 2014 to compare experiences in three states with markedly different policies: Kentucky, which expanded Medicaid, created a successful state Marketplace, and supported outreach efforts; Arkansas, which enacted the private option and a federal-state partnership Marketplace, but with legislative limitations on outreach; and Texas, which did not expand Medicaid and passed restrictions on navigators. We found that application rates, successful enrollment, and positive experiences with the ACA were highest in Kentucky, followed by Arkansas, with Texas performing worst. Limited awareness remains a critical barrier: Fewer than half of adults had heard some or a lot about the coverage expansions. Application assistance from navigators and others was the strongest predictor of enrollment, while Latino applicants were less likely than others to successfully enroll. Twice as many respondents felt that the ACA had helped them as hurt them (although the majority reported no direct impact), and advertising was strongly associated with perceptions of the law. State policy choices appeared to have had major impacts on enrollment experiences among low-income adults and their perceptions of the ACA. PMID:26056207

  1. Stream habitat and water-quality information for sites in the Buffalo River Basin and nearby basins of Arkansas, 2001-2002

    Science.gov (United States)

    Petersen, James C.

    2004-01-01

    The Buffalo River lies in north-central Arkansas and is a tributary of the White River. Stream-habitat and water-quality information are presented for 52 sites in the Buffalo River Basin and adjacent areas of the White River Basin. The information was collected during the summers of 2001 and 2002 to supplement fish community sampling during the same time period.

  2. Reactor BR2. Introduction

    International Nuclear Information System (INIS)

    The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given

  3. NEUTRONIC REACTOR FUEL COMPOSITION

    Science.gov (United States)

    Thurber, W.C.

    1961-01-10

    Uranium-aluminum alloys in which boron is homogeneously dispersed by adding it as a nickel boride are described. These compositions have particular utility as fuels for neutronic reactors, boron being present as a burnable poison.

  4. Pulsed fusion reactors

    International Nuclear Information System (INIS)

    This summer school specialized in examining specific fusion center systems. Papers on scientific feasibility are first presented: confinement of high-beta plasma, liners, plasma focus, compression and heating and the use of high power electron beams for thermonuclear reactors. As for technological feasibility, lectures were on the theta-pinch toroidal reactors, toroidal diffuse pinch, electrical engineering problems in pulsed magnetically confined reactors, neutral gas layer for heat removal, the conceptual design of a series of laser fusion power plants with ''Saturn'', implosion experiments and the problem of the targets, the high brightness lasers for plasma generation, and topping and bottoming cycles. Some problems common to pulsed reactors were examined: energy storage and transfer, thermomechanical and erosion effects in the first wall and blanket, the problems of tritium production, radiation damage and neutron activation in blankets, and the magnetic and inertial confinement

  5. Reactor BR2. Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2002-04-01

    The BR2 materials testing reactor is one of SCK-CEN's most important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. In 2001, the reactor was operated for a total of 123 days at a mean power of 59 MW in order to satisfy the irradiation conditions of the internal and external programmes using mainly the CALLISTO PWR loop. The mean consumption of fresh fuel elements was 5.26 per 1000 MWd. Main achievements in 2001 included the development of a three-dimensional full-scale model of the BR2 reactor for simulation and prediction of irradiation conditions for various experiments; the construction of the FUTURE-MT device designed for the irradiation of fuel plates under representative conditions of geometry, neutron spectrum, heat flux and thermal-hydraulic conditions and the development of in-pile instrumentation and a data acquisition system.

  6. Reactor BR2. Introduction

    Energy Technology Data Exchange (ETDEWEB)

    Gubel, P

    2001-04-01

    The BR2 is a materials testing reactor and is still one of SCK-CEN's important nuclear facilities. After an extensive refurbishment to compensate for the ageing of the installation, the reactor was restarted in April 1997. During the last three years, the availability of the installation was maintained at an average level of 97.6 percent. In the year 2000, the reactor was operated for a total of 104 days at a mean power of 56 MW. In 2000, most irradiation experiments were performed in the CALLISTO PWR loop. The report describes irradiations achieved or under preparation in 2000, including the development of advanced facilities and concept studies for new programmes. An overview of the scientific irradiation programmes as well as of the R and D programme of the BR2 reactor in 2000 is given.

  7. Reactor Neutrino Spectra

    CERN Document Server

    Hayes, A C

    2016-01-01

    We present a review of the antineutrino spectra emitted from reactors. Knowledge of these and their associated uncertainties are crucial for neutrino oscillation studies. The spectra used to-date have been determined by either conversion of measured electron spectra to antineutrino spectra or by summing over all of the thousands of transitions that makeup the spectra using modern databases as input. The uncertainties in the subdominant corrections to beta-decay plague both methods, and we provide estimates of these uncertainties. Improving on current knowledge of the antineutrino spectra from reactors will require new experiments. Such experiments would also address the so-called reactor neutrino anomaly and the possible origin of the shoulder observed in the antineutrino spectra measured in recent high-statistics reactor neutrino experiments.

  8. Experience with Kamini reactor

    International Nuclear Information System (INIS)

    Kamini is a 233U fuelled, 30 kW(th) research reactor. It is one of the best neutron source facility with a core average flux of 1012 n/cm2/s in IGCAR used for neutron radiography of active and nonradioactive objects, activation analysis and radiation physics research. The core consists of nine plate type fuel elements with a total fuel inventory of 590 g of 233U. Two safety control plates made of cadmium are used for start up and shutdown of the reactor. Three beam tubes, two-thimble irradiation site outside reflector and one irradiation site nearer to the core constitute the testing facilities of Kamini. Kamini attained first criticality on 29th October 96 and nominal power of 30 kW in September 1997. This paper covers the design features of the reactor, irradiation facilities and their utilities and operating experience of the reactor. (author)

  9. Reactor pressure boundary materials

    International Nuclear Information System (INIS)

    With a long-term operation of nuclear power plants, the component materials are degraded under severe reactor conditions such as neutron irradiation, high temperature, high pressure and corrosive environment. It is necessary to establish the reliable and practical technologies for improving and developing the component materials and for evaluating the mechanical properties. Especially, it is very important to investigate the technologies for reactor pressure boundary materials such as reactor vessel and pipings in accordance with their critical roles. Therefore, this study was focused on developing and advancing the microstructural/micro-mechanical evaluation technologies, and on evaluating the neutron irradiation characteristics and radiation effects analysis technology of the reactor pressure boundary materials, and also on establishing a basis of nuclear material property database

  10. Fusion Reactor Materials

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2002-04-01

    The objective of SCK-CEN's programme on fusion reactor materials is to contribute to the knowledge on the radiation-induced behaviour of fusion reactor materials and components as well as to help the international community in building the scientific and technical basis needed for the construction of the future reactor. Ongoing projects include: the study of the mechanical and chemical (corrosion) behaviour of structural materials under neutron irradiation and water coolant environment; the investigation of the characteristics of irradiated first wall material such as beryllium; investigations on the management of materials resulting from the dismantling of fusion reactors including waste disposal. Progress and achievements in these areas in 2001 are discussed.

  11. New reactor type proposed

    CERN Multimedia

    2003-01-01

    "Russian scientists at the Research Institute of Nuclear Power Engineering in Moscow are hoping to develop a new reactor that will use lead and bismuth as fuel instead of uranium and plutonium" (1/2 page).

  12. Special lecture on nuclear reactor

    International Nuclear Information System (INIS)

    This book gives a special lecture on nuclear reactor, which is divided into two parts. The first part has explanation on nuclear design of nuclear reactor and analysis of core with theories of integral transports, diffusion Nodal, transports Nodal and Monte Carlo skill parallel computer and nuclear calculation and speciality of transmutation reactor. The second part deals with speciality of nuclear reactor and control with nonlinear stabilization of nuclear reactor, nonlinear control of nuclear reactor, neural network and control of nuclear reactor, control theory of observer and analysis method of Adomian.

  13. Jet-Stirred Reactors

    OpenAIRE

    Herbinet, Olivier; Guillaume, Dayma

    2013-01-01

    The jet-stirred reactor is a type of ideal continuously stirred-tank reactor which is well suited for gas phase kinetic studies. It is mainly used to study the oxidation and the pyrolysis of hydrocarbon and oxygenated fuels. These studies consist in recording the evolution of the conversion of the reactants and of the mole fractions of reaction products as a function of different parameters such as reaction temperature, residence time, pressure and composition of the inlet gas. Gas chromatogr...

  14. Generation IV reactors: economics

    International Nuclear Information System (INIS)

    The operating nuclear reactors were built over a short period: no more than 10 years and today their average age rounds 18 years. EDF (French electricity company) plans to renew its reactor park over a far longer period : 30 years from 2020 to 2050. According to EDF this objective implies 3 constraints: 1) a service life of 50 to 60 years for a significant part of the present operating reactors, 2) to be ready to built a generation 3+ unit in 2020 which infers the third constraint: 3) to launch the construction of an EPR (European pressurized reactor) prototype as soon as possible in order to have it operating in 2010. In this scheme, generation 4 reactor will benefit the feedback experience of generation 3 and will take over in 2030. Economic analysis is an important tool that has been used by the generation 4 international forum to select the likely future reactor systems. This analysis is based on 4 independent criteria: the basic construction cost, the construction time, the operation and maintenance costs and the fuel cycle cost. This analysis leads to the evaluation of the global cost of electricity generation and of the total investment required for each of the reactor system. The former defines the economic competitiveness in a de-regulated energy market while the latter is linked to the financial risk taken by the investor. It appears, within the limits of the assumptions and models used, that generation 4 reactors will be characterized by a better competitiveness and an equivalent financial risk when compared with the previous generation. (A.C.)

  15. OECD Halden reactor project

    International Nuclear Information System (INIS)

    This report summarizes the activities of the OECD Halden Reactor Project for the year 1976. The main items reported on are: a) the process supervision and control which have focused on core monitoring and control, and operator-process communication; b) the fuel performance and safety behavior which have provided data and analytical descriptions of the thermal, mechanical and chemical behavior of fuel under various operating conditions; c) the reactor operations and d) the administration and finance

  16. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    A nuclear reactor fuel element comprising a column of vibration compacted fuel which is retained in consolidated condition by a thimble shaped plug. The plug is wedged into gripping engagement with the wall of the sheath by a wedge. The wedge material has a lower coefficient of expansion than the sheath material so that at reactor operating temperature the retainer can relax sufficient to accommodate thermal expansion of the column of fuel. (author)

  17. Department of Reactor Technology

    DEFF Research Database (Denmark)

    Risø National Laboratory, Roskilde

    The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included.......The general development of the Department of Reactor Technology at Risø during 1981 is presented, and the activities within the major subject fields are described in some detail. Lists of staff, publications, and computer programs are included....

  18. Characterization of the structure, clean-sand percentage, dissolved-solids concentrations, and estimated quantity of groundwater in the Upper Cretaceous Nacatoch Sand and Tokio Formation, Arkansas

    Science.gov (United States)

    Gillip, Jonathan A.

    2014-01-01

    The West Gulf Coastal Plain, Mississippi embayment, and underlying Cretaceous aquifers are rich in water resources; however, large parts of the aquifers are largely unusable because of large concentrations of dissolved solids. Cretaceous aquifers are known to have large concentrations of salinity in some parts of Arkansas. The Nacatoch Sand and the Tokio Formation of Upper Cretaceous age were chosen for investigation because these aquifers produce groundwater to wells near their outcrops and have large salinity concentrations away from their outcrop areas. Previous investigations have indicated that dissolved-solids concentrations of groundwater within the Nacatoch Sand, 2–20 miles downdip from the outcrop, render the groundwater as unusable for purposes requiring freshwater. Groundwater within the Tokio Formation also exhibits large concentrations of dissolved solids downdip. Water-quality data showing elevated dissolved-solids concentrations are limited for these Cretaceous aquifers because other shallower aquifers are used for water supply. Although not suitable for many uses, large, unused amounts of saline groundwater are present in these aquifers. Historical borehole geophysical logs were used to determine the geologic and hydrogeologic properties of these Cretaceous aquifers, as well as the quality of the groundwater within the aquifers. Based on the interpretation of borehole geophysical logs, in Arkansas, the altitude of the top of the Nacatoch Sand ranges from more than 200 to less than -4,000 feet; the structural high occurs in the outcrop area and the structural low occurs in southeastern Arkansas near the Desha Basin structural feature. The thickness of the Nacatoch Sand ranges from 0 to over 550 feet. The minimum thickness occurs where the formation pinches out in the outcrop area, and the maximum thickness occurs in the southwestern corner of Arkansas. Other areas of large thickness include the area of the Desha Basin structural feature in

  19. Moon base reactor system

    Science.gov (United States)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  20. BWR type nuclear reactor

    International Nuclear Information System (INIS)

    Purpose: To simplify the structure of an emergency core cooling system while suppressing the flow out of coolants upon rapture accidents in a coolant recycling device of BWR type reactors. Constitution: Recirculation pumps are located at a position higher than the reactor core in a pressure vessel, and the lower plenum is bisected vertically by a partition plate. Further, a gas-liquid separator is surrounded with a wall and the water level at the outer side of the wall is made higher than the water level in the inside of the wall. In this structure, coolants are introduced from the upper chamber in the lower plenum into the reactor core, and the steams generated in the reactor core are separated in the gas-liquid separator, whereby the separated liquid is introduced as coolants by way of the inner chamber into the lower chamber of the lower plenum and further sent by way of the outer chamber into the reactor core. Consequently, idle rotation of the recycling pumps due to the flow-in of saturated water is prevented and loss of coolants in the reactor core can also be prevented upon raptures in the pipeway and the driving section of the pump connected to the pressure vessel and in the bottom of the pressure vessel. (Horiuchi, T.)

  1. OECD Halden reactor project

    International Nuclear Information System (INIS)

    This is the nineteenth annual Report on the OECD Halden Reactor Project, describing activities at the Project during 1978, the last year of the 1976-1978 Halden Agreement. Work continued in two main fields: test fuel irradiation and fuel research, and computer-based process supervision and control. Project research on water reactor fuel focusses on various aspects of fuel behavior under normal, and off-normal transient conditions. In 1978, participating organisations continued to submit test fuel for irradiation in the Halden boiling heavy-water reactor, in instrumented test assemblies designed and manufactured by the Project. Work included analysis of the impact of fuel design and reactor operating conditions on fuel cladding behavior. Fuel performance modelling included characterization of thermal and mechanical behavior at high burn-up, of fuel failure modes, and improvement of data qualification procedures to reduce and quantify error bands on in-reactor measurements. Instrument development yielded new or improved designs for measuring rod temperature, internal pressure, axial neutron flux shape determination, and for detecting cladding defects. Work on computer-based methods of reactor supervision and control included continued development of a system for predictive core surveillance, and of special mathematical methods for core power distribution control

  2. Geologic map of the St. Joe quadrangle, Searcy and Marion Counties, Arkansas

    Science.gov (United States)

    Hudson, Mark R.; Turner, Kenzie J.

    2009-01-01

    This map summarizes the geology of the St. Joe 7.5-minute quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the St. Joe quadrangle lies within the Springfield Plateau, a topographic surface generally held up by Mississippian cherty limestone. The quadrangle also contains isolated mountains (for example, Pilot Mountain) capped by Pennsylvanian rocks that are erosional outliers of the higher Boston Mountains plateau to the south. Tomahawk Creek, a tributary of the Buffalo River, flows through the eastern part of the map area, enhancing bedrock erosion. Exposed bedrock of this region comprises an approximately 1,300-ft-thick sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. The geology of the St. Joe quadrangle was mapped by McKnight (1935) as part of a larger area at 1:125,000 scale. The current map confirms many features of this previous study, but it also identifies new structures and uses a revised stratigraphy. Mapping for this study was conducted by field inspection of numerous sites and was compiled as a 1:24,000-scale geographic information system (GIS) database. Locations and elevations of sites were determined with the aid of a global positioning satellite receiver and a hand-held barometric altimeter that was frequently recalibrated at points of known elevation. Hill-shade-relief and slope maps derived from a U.S. Geological Survey 10-m digital elevation model as well as U.S. Geological Survey orthophotographs from 2000 were used to help trace ledge-forming units between field traverses within the Upper Mississippian and Pennsylvanian part of the stratigraphic sequence. Strikes and dips of beds were typically measured along stream drainages or at well-exposed ledges. Beds dipping less

  3. The Occurrence of Knickpoints in Soluble Strata in the Buffalo River Basin, Arkansas

    Science.gov (United States)

    Thaler, E.; Covington, M. D.; Myre, J. M.; Perne, M.; Holcomb, G.

    2014-12-01

    Prior field and theoretical work has suggested that bedrock channels adjust to lower stream power when encountering highly soluble strata, exhibiting an increase in channel width and/or a decrease in channel slope. However, in apparent contradiction to this expectation, many channels within the Buffalo River Basin, Arkansas, contain knickpoints, in the form of waterfalls and slot canyons, that are developed at the contact between the Mississippian Batesville Sandstone and the underlying Boone Limestone. To improve understanding of bedrock channel response to contrasts in rock solubility, longitudinal surveys were conducted in three channels that cross the Boone Limestone. Additionally, channel widths and a profile were obtained for the main stem of the Buffalo River using aerial photography and a digital elevation model. Schmidt scores for the Boone and Batesville suggest that the two strata have similar compressive strengths, which is a measure of relative resistance to mechanical erosion. Two of the four studied reaches show significant knickpoint development, and in both cases the basin area above the knickpoint is less than 3 km2. One possible explanation is that these knickpoints have been arrested at a critical threshold basin area. However, at least four other such knickpoints are known from the area, and in all cases the knickpoint is highly correlated to the contact rather than a specific basin area, suggesting that the properties of the strata are an important factor. We identify three potential mechanisms that may often act in concert to develop knickpoints at contacts with underlying soluble rocks. (1) If chemical erosion in the soluble reach outpaces uplift, and knickpoint retreat through the overlying layer is sufficiently slow, then a knickpoint will develop. (2) Karstification can divert geomorphic work to the subsurface, resulting in a steep surface channel and possible stalling of upstream knickpoint migration within the soluble strata. (3) The

  4. Reactor physics and economic aspects of the CANDU reactor system

    International Nuclear Information System (INIS)

    A history of the development of the CANDU system is given along with a fairly detailed description of the 600 MW(e) CANDU reactor. Reactor physics calculation methods are described, as well as comparisons between calculated reactor physics parameters and those measured in research and power reactors. An examination of the economics of CANDU in the Ontario Hydro system and a comparison between fossil fuelled and light water reactors is presented. Some physics, economics and resources aspects are given for both low enriched uranium and thorium-fuelled CANDU reactors. Finally the RβD program in Advanced Fuel Cycles is briefly described

  5. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    Energy Technology Data Exchange (ETDEWEB)

    P. Delmolino

    2005-05-06

    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  6. Fast breeder reactor research

    International Nuclear Information System (INIS)

    Full text: The meeting was attended by 15 participants from seven countries and two international organizations. The Eighth Annual Meeting of the International Working Group on Fast Reactors (IWGFR) was attended by representatives from France, Fed. Rep. Germany, Italy, Japan, United Kingdom, Union of Soviet Socialist Republics and the United States of America - countries that have made significant progress in developing the technology and physics of sodium cooled fast reactors and have extensive national programmes in this field - as well as by representatives of the Commission of the European Communities and the IAEA. The design of fast-reactor power plants is a more difficult task than developing facilities with thermal reactors. Different reactor kinetics and dynamics, a hard neutron spectrum, larger integral doses of fuel and structural material irradiation, higher core temperatures, the use of an essentially novel coolant, and, as a result of all these factors, the additional reliability and safety requirements that are imposed on the planning and operation of sodium cooled fast reactors - all these factors pose problems that can be solved comprehensively only by countries with a high level of scientific and technical development. The exchange of experience between these countries and their combined efforts in solving the fundamental problems that arise in planning, constructing and operating fast reactors are promoting technical progress and reducing the relative expenditure required for various studies on developing and introducing commercial fast reactors. For this reason, the meeting concentrated on reviewing and discussing national fast reactor programmes. The situation with regard to planning, constructing and operating fast experimental and demonstration reactors in the countries concerned, the experience accumulated in operating them, the difficulties arising during operation and ways of over-coming them, the search for optimal designs for the power

  7. An analysis of the design and implementation of elementary science methods class instruction in colleges and universities in Arkansas

    Science.gov (United States)

    Lee, Carole K.

    This study aims to understand the design and implementation of elementary methods classes focused in science instruction by teacher educators in the colleges and universities in the state of Arkansas. All 18 institutions with an Early Childhood Education program approved by the Arkansas Department of Education were reviewed with interviews, site visits and data analysis. The research questions are: (1) What goals do teacher educators express with respect to the preparation of preservice elementary teachers for the teaching of science? (2) What components of methods classes for teaching of elementary science examined relate to each of Feiman-Nemser's conceptual orientations in teacher education? (3) What challenges do teacher educators state that they encounter when they plan and teach the methods classes for teaching elementary science? (4) What specific scientific knowledge or skills are emphasized in the methods classes? Enrollment data of the Early Childhood Education program of the 18 institutions were sought. Data collected from the interviews of 16 teacher educators were transcribed according to Feiman-Nemser's five conceptual orientations in teacher education. The findings reveal the complexities and diverse nature of the science-focused method classes as they are affected by the perceptions and academic backgrounds of the teacher educators, the field experiences that preservice teachers have to teach science in the elementary schools, and the science teaching pedagogy and content knowledge provided by the teacher educators. Results show that not all methods classes are focused mainly in science teaching methods and science knowledge; some are an integration of mathematics and science or a blended curriculum with several disciplines. Most institutions do not provide science-related field experiences for preservice teachers. One common theme that emerges in the lesson observations is that all teacher educators use hands-on activities to illustrate the

  8. Geodatabase of the datasets used to represent the six subunits of the Texas Coastal Uplands and Mississippi Embayment aquifer system, Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, and Texas

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This geodatabase includes spatial datasets that represent the Texas Coastal Uplands and Mississippi Embayment aquifer system in the States of Alabama, Arkansas,...

  9. BR2 Reactor: Introduction

    International Nuclear Information System (INIS)

    The irradiations in the BR2 reactor are in collaboration with or at the request of third parties such as the European Commission, the IAEA, research centres and utilities, reactor vendors or fuel manufacturers. The reactor also contributes significantly to the production of radioisotopes for medical and industrial applications, to neutron silicon doping for the semiconductor industry and to scientific irradiations for universities. Along the ongoing programmes on fuel and materials development, several new irradiation devices are in use or in design. Amongst others a loop providing enhanced cooling for novel materials testing reactor fuel, a device for high temperature gas cooled fuel as well as a rig for the irradiation of metallurgical samples in a Pb-Bi environment. A full scale 3-D heterogeneous model of BR2 is available. The model describes the real hyperbolic arrangement of the reactor and includes the detailed 3-D space dependent distribution of the isotopic fuel depletion in the fuel elements. The model is validated on the reactivity measurements of several tens of BR2 operation cycles. The accurate calculations of the axial and radial distributions of the poisoning of the beryllium matrix by 3He, 6Li and 3T are verified on the measured reactivity losses used to predict the reactivity behavior for the coming decades. The model calculates the main functionals in reactor physics like: conventional thermal and equivalent fission neutron fluxes, number of displacements per atom, fission rate, thermal power characteristics as heat flux and linear power density, neutron/gamma heating, determination of the fission energy deposited in fuel plates/rods, neutron multiplication factor and fuel burn-up. For each reactor irradiation project, a detailed geometry model of the experimental device and of its neighborhood is developed. Neutron fluxes are predicted within approximately 10 percent in comparison with the dosimetry measurements. Fission rate, heat flux and

  10. Scaleable, High Efficiency Microchannel Sabatier Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A Microchannel Sabatier Reactor System (MSRS) consisting of cross connected arrays of isothermal or graded temperature reactors is proposed. The reactor array...

  11. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Takeshi; Iida, Masaaki; Moriki, Yasuyuki

    1994-10-18

    A reactor core is divided into a plurality of coolants flowrate regions, and electromagnetic pumps exclusively used for each of the flowrate regions are disposed to distribute coolants flowrates in the reactor core. Further, the flowrate of each of the electromagnetic pumps is automatically controlled depending on signals from a temperature detector disposed at the exit of the reactor core, so that the flowrate of the region can be controlled optimally depending on the burning of reactor core fuels. Then, the electromagnetic pumps disposed for every divided region are controlled respectively, so that the coolants flowrate distribution suitable to each of the regions can be attained. Margin for fuel design is decreased, fuels are used effectively, as well as an operation efficiency can be improved. Moreover, since the electromagnetic pump has less flow resistance compared with a mechanical type pump, and flow resistance of the reactor core flowrate control mechanism is eliminated, greater circulating flowrate can be ensured after occurrence of accident in a natural convection using a buoyancy of coolants utilizable for after-heat removal as a driving force. (N.H.).

  12. Reactor coolant cleanup facility

    International Nuclear Information System (INIS)

    A depressurization device is disposed in pipelines upstream of recycling pumps of a reactor coolant cleanup facility to reduce a pressure between the pressurization device and the recycling pump at the downstream, thereby enabling high pressure coolant injection from other systems by way of the recycling pumps. Upon emergency, the recycling pumps of the coolant cleanup facility can be used in common to an emergency reactor core cooling facility and a reactor shutdown facility. Since existent pumps of the emergency reactor core cooling facility and the reactor shutdown facility which are usually in a stand-by state can be removed, operation confirmation test and maintenance for equipments in both of facilities can be saved, so that maintenance and reliability of the plant are improved and burdens on operators can also be mitigated. Moreover, low pressure design can be adopted for a non-regenerative heat exchanger and recycling coolant pumps, which enables to improve the reliability and economical property due to reduction of possibility of leakage. (N.H.)

  13. EBT reactor analysis

    International Nuclear Information System (INIS)

    This report summarizes the results of a recent ELMO Bumpy Torus (EBT) reactor study that includes ring and core plasma properties with consistent treatment of coupled ring-core stability criteria and power balance requirements. The principal finding is that constraints imposed by these coupling and other physics and technology considerations permit a broad operating window for reactor design optimization. Within this operating window, physics and engineering systems analysis and cost sensitivity studies indicate that reactors with approx. 6 to 10%, P approx. 1200 to 1700 MW(e), wall loading approx. 1.0 to 2.5 MW/m2, and recirculating power fraction (including ring-sustaining power and all other reactors auxiliaries) approx. 10 to 15% are possible. A number of concept improvements are also proposed that are found to offer the potential for further improvement of the reactor size and parameters. These include, but are not limited to, the use of: (1) supplementary coils or noncircular mirror coils to improve magnetic geometry and reduce size, (2) energetic ion rings to improve ring power requirements, (3) positive potential to enhance confinement and reduce size, and (4) profile control to improve stability and overall fusion power density

  14. Generalities about nuclear reactors

    International Nuclear Information System (INIS)

    From Zoe, the first nuclear reactor, till the current EPR, the French nuclear industry has always advanced by profiting from the feedback from dozens of years of experience and operations, in particular by drawing lessons from the most significant events in its history, such as the Fukushima accident. The new generations of reactors must improve safety and economic performance so that the industry maintain its legitimacy and its share in the production of electricity. This article draws the history of nuclear power in France, gives a brief description of the pressurized water reactor design, lists the technical features of the different versions of PWR that operate in France and compares them with other types of reactors. The feedback experience concerning safety, learnt from the major nuclear accidents Three Miles Island (1979), Chernobyl (1986) and Fukushima (2011) is also detailed. Today there are 26 third generation reactors being built in the world: 4 EPR (1 in Finland, 1 in France and 2 in China); 2 VVER-1200 in Russia, 8 AP-1000 (4 in China and 4 in the Usa), 8 APR-1400 (4 in Korea and 4 in UAE), and 4 ABWR (2 in Japan and 2 in Taiwan)

  15. Reactor Structural Materials: Reactor Pressure Vessel Steels

    Energy Technology Data Exchange (ETDEWEB)

    Chaouadi, R

    2000-07-01

    The objectives of SCK-CEN's R and D programme on Rector Pressure Vessel (RPV) Steels are:(1) to complete the fracture toughness data bank of various reactor pressure vessel steels by using precracked Charpy specimens that were tested statically as well as dynamically; (2) to implement the enhanced surveillance approach in a user-friendly software; (3) to improve the existing reconstitution technology by reducing the input energy (short cycle welding) and modifying the stud geometry. Progress and achievements in 1999 are reported.

  16. Mimic of OSU research reactor

    International Nuclear Information System (INIS)

    The Ohio State University research reactor (OSURR) is undergoing improvements in its research and educational capabilities. A computer-based digital data acquisition system, including a reactor system mimic, will be installed as part of these improvements. The system will monitor the reactor system parameters available to the reactor operator either in digital parameters available to the reactor operator either in digital or analog form. The system includes two computers. All the signals are sent to computer 1, which processes the data and sends the data through a serial port to computer 2 with a video graphics array VGA monitor, which is utilized to display the mimic system of the reactor

  17. Methanation assembly using multiple reactors

    Science.gov (United States)

    Jahnke, Fred C.; Parab, Sanjay C.

    2007-07-24

    A methanation assembly for use with a water supply and a gas supply containing gas to be methanated in which a reactor assembly has a plurality of methanation reactors each for methanating gas input to the assembly and a gas delivery and cooling assembly adapted to deliver gas from the gas supply to each of said methanation reactors and to combine water from the water supply with the output of each methanation reactor being conveyed to a next methanation reactor and carry the mixture to such next methanation reactor.

  18. MINT research reactor safety program

    Energy Technology Data Exchange (ETDEWEB)

    Mohamad Idris bin Taib [Division of Special Project, Malaysian Institute for Nuclear Technology Research (MINT), Bangi (Malaysia)

    2000-11-01

    Malaysian Institute for Nuclear Technology Research (MINT) Research Reactor Safety Program has been done along with Reactor Power Upgrading Project, Reactor Safety Upgrading Project and Development of Expert System for On-Line Nuclear Process Control Project. From 1993 up to date, Neutronic and Thermal-hydraulics analysis, Probabilistic Safety Assessment as well as installation of New 2 MW Secondary Cooling System were done. Installations of New Reactor Building Ventilation System, Reactor Monitoring System, Updating of Safety Analysis Report and Upgrading Primary Cooling System are in progress. For future activities, Reactor Modeling will be included to add present activities. (author)

  19. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  20. International Thermonuclear Experimental Reactor

    International Nuclear Information System (INIS)

    An international design team comprised of members from Canada, Europe, Japan, the Soviet Union, and the United States of America, are designing an experimental fusion test reactor. The engineering and testing objectives of this International Thermonuclear Experimental Reactor (ITER) are to validate the design and to demonstrate controlled ignition, extended burn of a deuterium and tritium plasma, and achieve steady state using technology expected to be available by 1990. The concept maximizes flexibility while allowing for a variety of plasma configurations and operating scenarios. During physics phase operation, the machine produces a 22 MA plasma current. In the technology phase, the machine can be reconfigured with a thicker shield and a breeding blanket to operate with an 18 MA plasma current at a major radius of 5.5 meters. Canada's involvement in the areas of safety, facility design, reactor configuration and maintenance builds on our internationally recognized design and operational expertise in developing tritium processes and CANDU related technologies

  1. Licensed operating reactors

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission's monthly Licensed Operating Reactors Status Summary Report provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management, from the Headquarters Staff of NRC's Office of Inspection and Enforcement, from NRC's Regional Offices, and from utilities. This report is divided into three sections: the first contains monthly highlights and statistics for commercial operating units, and errata from previously reported data; the second is a compilation of detailed information on each unit, provided by NRC Regional Offices, IE Headquarters and the Utilities; and the third section is an appendix for miscellaneous information such as spent fuel storage capability, reactor years of experience and non-power reactors in the United States

  2. Licensed operating reactors

    International Nuclear Information System (INIS)

    THE OPERATING UNITS STATUS REPORT - LICENSED OPERATING REACTORS provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management from the Headquarters staff of NRC's Office of Enforcement (OE), from NRC's Regional Offices, and from utilities. The three sections of the report are: monthly highlights and statistics for commercial operating units, and errata from previously reported data; a compilation of detailed information on each unit, provided by NRC's Regional Offices, OE Headquarters and the utilities; and an appendix for miscellaneous information such as spent fuel storage capability, reactor-years of experience and non-power reactors in the US

  3. Licensed operating reactors

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission's monthly LICENSED OPERATING REACTORS Status Summary Report provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management, from the Headquarters Staff of NRC's Office of Inspection and Enforcement, from NRC's Regional Offices, and from utilities. This report is divided into three sections: the first contains monthly highlights and statistics for commercial operating units, and errata from previously reported data; the second is a compilation of detailed information on each unit, provided by NRC Regional Offices, IE Headquarters and the Utilities; and the third section is an appendix for miscellaneous information such as spent fuel storage capability, reactor years of experience and non-power reactors in the United States

  4. Reactor safety equipments

    International Nuclear Information System (INIS)

    Purpose: To positively recover radioactive substances discharged in a dry well at the time of failure of a reactor. Constitution: In addition to the emergency gas treating system fitted to a reactor building, a purification system connected through a pipeline to the dry well is arranged in the reactor building. This purification system is connected through pipes fitted to the dry well to forced circulation device, heat exchanger, and purification device. The atmosphere of high pressure steam gases in the dry well is derived to the heat exchanger for cooling, and then radioactive substances which are contained in the gases are removed by filter sets charged with the HEPA filters and the HECA filters. At last, there gases are returned to dry well by circulation pump, repeat this process. (Kamimura, M.)

  5. Licensed operating reactors

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission's monthly LICENSED OPERATING REACTORS Status Summary Report provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management, from the Headquarters Staff of NRC's Office of Inspection and Enforcement, from NRC's Regional Offices, and from utilities. This report is divided into three sections: the first contains monthly highlights and statistics for commercial operating units, and errata from previously reported data; the second is a compilation of detailed information on each unit, provided by NRC Regional Offices, IE Headquarters and the utilities; and the third section is an appendix for miscellaneous information such as spent fuel storage capability, reactor years of experience and non-power reactors in the United States

  6. Welding and reactor safety

    International Nuclear Information System (INIS)

    The high safety requirements which must be demanded of the quality of the welded joints in reactor technique have so far not been fulfilled in all cases. The errors occuring have caused considerable loss of availability and high material costs. They were not, however, so serious that one need have feared any immediate danger to the personnel or to the environment. The safety devices of reactor plants were only called upon in a few cases and to these they responded perfectly. The intensive efforts to complete and improve the specifications are to contribute to that in future, the reactor plants can be counted even more so as one of the safest technical plants ever. (orig./LH)

  7. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  8. Reactor operation experience

    International Nuclear Information System (INIS)

    Since the TRIGA Users Conference in Helsinki 1970 the TRIGA reactor Vienna was in operation without any larger undesired shutdown. The integrated thermal power production by August 15 1972 accumulated to 110 MWd. The TRIGA reactor is manly used for training of students, for scientific courses and research work. Cooperation with industry increased in the last two years either in form of research or in performing training courses. Close cooperation is also maintained with the IAEA, samples are irradiated and courses on various fields are arranged. Maintenance work was performed on the heat exchanger and to replace the shim rod magnet. With the view on the future power upgrading nine fuel elements type 110 have been ordered recently. Experiments, performed currently on the reactor are presented in details

  9. The MNSR reactor

    International Nuclear Information System (INIS)

    This tank-in-pool reactor is based on the same design concept as the Canadian Slowpoke. The core is a right circular cylinder, 24 cm diameter by 25 cm long, containing 411 fuel pin positions. The pins are HEU-Aluminium alloy, 0.5 cm in diameter. Critical mass is about 900 g. The reactor has a single cadmium control rod. The back-up shutdown system is the insertion of a cadmium capsule in a core position. Excess reactivity is limited to 3.5mk. In both the MNSR and Slowpoke, the insertion of the maximum excess reactivity results in a power transient limited by the coolant/moderator temperature to safe values, independent of any operator action. This reactor is used primarily in training and neutron activation analysis. Up to 64 elements have been analyzed in a great variety of different disciplines. (author)

  10. Nuclear Rocket Engine Reactor

    CERN Document Server

    Lanin, Anatoly

    2013-01-01

    The development of a nuclear rocket engine reactor (NRER ) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  11. Fusion reactor materials

    International Nuclear Information System (INIS)

    This is the fifteenth in a series of semiannual technical progress reports on fusion reactor materials. This report combines research and development activities which were previously reported separately in the following progress reports: Alloy Development for Irradiation Performance; Damage Analysis and Fundamental Studies; Special purpose Materials. These activities are concerned principally with the effects of the neutronic and chemical environment on the properties and performance of reactor materials; together they form one element of the overall materials programs being conducted in support of the Magnetic Fusion Energy Program of the U.S. Department of Energy. The Fusion Reactor Materials Program is a national effort involving several national laboratories, universities, and industries. The purpose of this series of reports is to provide a working technical record for the use of the program participants, and to provide a means of communicating the efforts of materials scientists to the rest of the fusion community, both nationally and worldwide

  12. Safety systems of heavy water reactors and small power reactors

    International Nuclear Information System (INIS)

    After introductional descriptions of heavy water reactors and natural circulation boiling water reactors the safety philosophy and safety systems like ECCS, residual heat removal, protection systems etc., are described. (RW)

  13. Hydrogeochemical and stream-sediment reconnaissance, orientation study, Ouachita Mountain area, Arkansas. National Uranium Resource Evaluation Program

    International Nuclear Information System (INIS)

    A hydrogeochemical ground water orientation study was conducted in the multi-mineralized area of the Ouachita Mountains, Arkansas in order to evaluate the usefulness of ground water as a sampling medium for uranium exploration in similar areas. Ninety-three springs and nine wells were sampled in Clark, Garland, Hot Springs, Howard, Montgomery, Pike, Polk, and Sevier Counties. Manganese, barite, celestite, cinnabar, stibnite, copper, lead, and zinc are present. The following parameters were determined: pH, conductivity, alkalinity, U, Br, Cl, F, He, Mn, Na, V, Al, Dy, NO3, NH3, SO4, and PO4. The minerals appear to significantly affect the chemistry of the ground water. This report is issued in draft form, without detailed technical and copy editing. This was done to make the report available to the public before the end of the National Uranium Resource Evaluation

  14. Metals, Parasites, and Environmental Conditions Affecting Breeding Populations of Spotted Salamanders (Ambystoma maculatum) in Northern Arkansas, USA.

    Science.gov (United States)

    DeMali, Heather M; Trauth, Stanley E; Bouldin, Jennifer L

    2016-06-01

    The spotted salamander (Ambystoma maculatum) is indigenous to northern Arkansas, and several breeding sites are known to exist in the region. Spotted salamanders (n = 17) were collected and examined for parasites and only three females harbored nematodes (Physaloptera spp.). Chronic aquatic bioassays were conducted using water collected from eight breeding ponds during different hydroperiod events. No lethal or sublethal effects were measured in Ceriodaphnia dubia; however, decreased growth and survival were seen in Pimephales promelas. Aqueous, sediment, and salamander hepatic samples were analyzed for As, Cd, Cu, Pb, and Ni. Metal analysis revealed possible increased metal exposure following precipitation, with greatest metal concentrations measured in sediment samples. Hepatic metal concentrations were similar in parasitized and non-parasitized individuals, and greatest Pb concentrations were measured following normal precipitation events. Determining environmental stressors of amphibians, especially during their breeding and subsequent larval life stage, is imperative to improve species conservation. PMID:26886425

  15. AREVA's nuclear reactors portfolio

    International Nuclear Information System (INIS)

    A reasonable assumption for the estimated new build market for the next 25 years is over 340 GWe net. The number of prospect countries is growing almost each day. To address this new build market, AREVA is developing a comprehensive portfolio of reactors intended to meet a wide range of power requirements and of technology choices. The EPR reactor is the flagship of the fleet. Intended for large power requirements, the four first EPRs are being built in Finland, France and China. Other countries and customers are in view, citing just two examples: the Usa where the U.S. EPR has been selected as the technology of choice by several U.S utilities; and the United Kingdom where the Generic Design Acceptance process of the EPR design submitted by AREVA and EDF is well under way, and where there is a strong will to have a plant on line in 2017. For medium power ranges, the AREVA portfolio includes a boiling water reactor and a pressurized water reactor which both offer all of the advantages of an advanced plant design, with excellent safety performance and competitive power generation cost: -) KERENA (1250+ MWe), developed in collaboration with several European utilities, and in particular with Eon; -) ATMEA 1 (1100+ MWe), a 3-loop evolutionary PWR which is being developed by AREVA and Mitsubishi. AREVA is also preparing the future and is deeply involved into Gen IV concepts. It has developed the ANTARES modular HTR reactor (pre-conceptual design completed) and is building upon its vast Sodium Fast Reactor experience to take part into the development of the next prototype. (author)

  16. Oscillatory flow chemical reactors

    Directory of Open Access Journals (Sweden)

    Slavnić Danijela S.

    2014-01-01

    Full Text Available Global market competition, increase in energy and other production costs, demands for high quality products and reduction of waste are forcing pharmaceutical, fine chemicals and biochemical industries, to search for radical solutions. One of the most effective ways to improve the overall production (cost reduction and better control of reactions is a transition from batch to continuous processes. However, the reactions of interests for the mentioned industry sectors are often slow, thus continuous tubular reactors would be impractically long for flow regimes which provide sufficient heat and mass transfer and narrow residence time distribution. The oscillatory flow reactors (OFR are newer type of tube reactors which can offer solution by providing continuous operation with approximately plug flow pattern, low shear stress rates and enhanced mass and heat transfer. These benefits are the result of very good mixing in OFR achieved by vortex generation. OFR consists of cylindrical tube containing equally spaced orifice baffles. Fluid oscillations are superimposed on a net (laminar flow. Eddies are generated when oscillating fluid collides with baffles and passes through orifices. Generation and propagation of vortices create uniform mixing in each reactor cavity (between baffles, providing an overall flow pattern which is close to plug flow. Oscillations can be created by direct action of a piston or a diaphragm on fluid (or alternatively on baffles. This article provides an overview of oscillatory flow reactor technology, its operating principles and basic design and scale - up characteristics. Further, the article reviews the key research findings in heat and mass transfer, shear stress, residence time distribution in OFR, presenting their advantages over the conventional reactors. Finally, relevant process intensification examples from pharmaceutical, polymer and biofuels industries are presented.

  17. Reactor Materials Research

    International Nuclear Information System (INIS)

    The activities of SCK-CEN's Reactor Materials Research Department for 2001 are summarised. The objectives of the department are: (1) to evaluate the integrity and behaviour of structural materials used in nuclear power industry; (2) to conduct research to unravel and understand the parameters that determine the material behaviour under or after irradiation; (3) to contribute to the interpretation, the modelling of the material behaviour and to develop and assess strategies for optimum life management of nuclear power plant components. The programmes within the department are focussed on studies concerning (1) Irradiation Assisted Stress Corrosion Cracking (IASCC); (2) nuclear fuel; and (3) Reactor Pressure Vessel Steel

  18. Nuclear reactor simulator

    International Nuclear Information System (INIS)

    The Nuclear Reactor Simulator was projected to help the basic training in the formation of the Nuclear Power Plants operators. It gives the trainee the opportunity to see the nuclear reactor dynamics. It's specially indicated to be used as the support tool to NPPT (Nuclear Power Preparatory Training) from NUS Corporation. The software was developed to Intel platform (80 x 86, Pentium and compatible ones) working under the Windows operational system from Microsoft. The program language used in development was Object Pascal and the compiler used was Delphi from Borland. During the development, computer algorithms were used, based in numeric methods, to the resolution of the differential equations involved in the process. (author)

  19. Diagnostics for hybrid reactors

    International Nuclear Information System (INIS)

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  20. Small mirror fusion reactors

    International Nuclear Information System (INIS)

    Basic requirements for the pilot plants are that they produce a net product and that they have a potential for commercial upgrade. We have investigated a small standard mirror fusion-fission hybrid, a two-component tandem mirror hybrid, and two versions of a field-reversed mirror fusion reactor--one a steady state, single cell reactor with a neutral beam-sustained plasma, the other a moving ring field-reversed mirror where the plasma passes through a reaction chamber with no energy addition

  1. Reactor neutron dosimetry

    International Nuclear Information System (INIS)

    An analysis of requirements and possibilities for experimental neutron spectrum determination during the reactor pressure vessel surveil lance programme is given. Fast neutron spectrum and neutron dose rate were measured in the Fast neutron irradiation facility of our TRIGA reactor. It was shown that the facility can be used for calibration of neutron dosimeters and for irradiation of samples sensitive to neutron radiation. The investigation of the unfolding algorithm ITER was continued. Based on this investigations are two specialized unfolding program packages ITERAD and ITERGS written this year. They are able to unfold data from activation detectors and NaI(T1) gamma spectrometer respectively

  2. Perspectives on reactor safety

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course

  3. Perspectives on reactor safety

    Energy Technology Data Exchange (ETDEWEB)

    Haskin, F.E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Camp, A.L. [Sandia National Labs., Albuquerque, NM (United States)

    1994-03-01

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  4. Nuclear reactor constructions

    International Nuclear Information System (INIS)

    A nuclear reactor construction comprising a reactor core submerged in a pool of liquid metal coolant in a primary vessel which is suspended from the roof structure of a containment vault. Control rods supported from the roof structure are insertable in the core which is carried on a support structure from the wall of the primary vessel. To prevent excessive relaxation of the support structure whereby the control rods would be displaced relative to the core, the support structure incorporates a normally inactive secondary structure designed to become effective in bracing the primary structure against further relaxation beyond a predetermined limit. (author)

  5. Fusion Reactor Materials

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2000-07-01

    SCK-CEN's research and development programme on fusion reactor materials includes: (1) the study of the mechanical behaviour of structural materials under neutron irradiation (including steels, inconel, molybdenum, chromium); (2) the determination and modelling of the characteristics of irradiated first wall materials such as beryllium; (3) the detection of abrupt electrical degradation of insulating ceramics under high temperature and neutron irradiation; (4) the study of the dismantling and waste disposal strategy for fusion reactors.; (5) a feasibility study for the testing of blanket modules under neutron radiation. Main achievements in these topical areas in the year 1999 are summarised.

  6. Reactor gamma spectrometry: status

    International Nuclear Information System (INIS)

    Current work is described for Compton Recoil Gamma-Ray Spectrometry including developments in experimental technique as well as recent reactor spectrometry measurements. The current status of the method is described concerning gamma spectromoetry probe design and response characteristics. Emphasis is given to gamma spectrometry work in US LWR and BR programs. Gamma spectrometry in BR environments are outlined by focussing on start-up plans for the Fast Test Reactor (FTR). Gamma spectrometry results are presented for a LWR pressure vessel mockup in the Poolside Critical Assembly (PCA) at Oak Ridge National Laboratory

  7. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2002-04-01

    The activities of SCK-CEN's Reactor Materials Research Department for 2001 are summarised. The objectives of the department are: (1) to evaluate the integrity and behaviour of structural materials used in nuclear power industry; (2) to conduct research to unravel and understand the parameters that determine the material behaviour under or after irradiation; (3) to contribute to the interpretation, the modelling of the material behaviour and to develop and assess strategies for optimum life management of nuclear power plant components. The programmes within the department are focussed on studies concerning (1) Irradiation Assisted Stress Corrosion Cracking (IASCC); (2) nuclear fuel; and (3) Reactor Pressure Vessel Steel.

  8. Ecological response to hydrological variability and catchment development: Insights from a shallow oxbow lake in Lower Mississippi Valley, Arkansas.

    Science.gov (United States)

    Bhattacharya, Ruchi; Hausmann, Sonja; Hubeny, J Bradford; Gell, Peter; Black, Jessica L

    2016-11-01

    The ecological response of shallow oxbow lakes to variability in hydrology and catchment development in large river floodplain ecosystems (RFE) in Arkansas remains largely unknown. Investigating these responses will advance our understanding of ecological evolution of oxbow lakes in response to the major environmental drivers, which will establish baseline conditions required to develop effective management practices for RFE. In this pilot study, we examined the potential of using a dated surface sediment core from Adams Bayou, a floodplain lake located within the Cache-Lower White River Ramsar site in SE Arkansas. Stratigraphic records of diatoms and sediment geochemistry were used to ascertain variation in Adams Bayou's ecological condition. During 1968-2008, in response to hydrological and anthropogenic changes, Adams Bayou's diatom assemblages progressed from predominantly benthic (Gomphonema parvulum and Meridion circulare) to primarily planktonic assemblage (Aulacoseira granulata and Cyclotella meneghiniana), along with a decrease in magnetic susceptibility (k) and % silt. Statistical analyses reveled that during 1968-2000, higher hydrological connectivity and catchment alterations drove Adams Bayou's ecosystem. After 2000, lower hydrological connectivity and increase in cultivation were the major drivers. The potential impact of increasing air temperature was also noted. The shift in Adams Bayou from a connected, clear, mesotrophic state to a relatively isolated, turbid and nutrient enriched state is consistent with regime shift models and highlights its sensitivity to a combination of environmental stresses prevalent in the catchment. Although fluvial systems pose challenges in establishing clear chronologies, oxbow lake sediments can be a effective paleoecological archives. Our work provides clear evidence for the change in the ecological character of this wetland of international significance and flags the need for a wider assessment of water bodies

  9. Methods for estimating annual exceedance probability discharges for streams in Arkansas, based on data through water year 2013

    Science.gov (United States)

    Wagner, Daniel M.; Krieger, Joshua D.; Veilleux, Andrea G.

    2016-08-04

    In 2013, the U.S. Geological Survey initiated a study to update regional skew, annual exceedance probability discharges, and regional regression equations used to estimate annual exceedance probability discharges for ungaged locations on streams in the study area with the use of recent geospatial data, new analytical methods, and available annual peak-discharge data through the 2013 water year. An analysis of regional skew using Bayesian weighted least-squares/Bayesian generalized-least squares regression was performed for Arkansas, Louisiana, and parts of Missouri and Oklahoma. The newly developed constant regional skew of -0.17 was used in the computation of annual exceedance probability discharges for 281 streamgages used in the regional regression analysis. Based on analysis of covariance, four flood regions were identified for use in the generation of regional regression models. Thirty-nine basin characteristics were considered as potential explanatory variables, and ordinary least-squares regression techniques were used to determine the optimum combinations of basin characteristics for each of the four regions. Basin characteristics in candidate models were evaluated based on multicollinearity with other basin characteristics (variance inflation factor flood region. Average standard errors of prediction of the generalized least-squares models ranged from 32.76 to 59.53 percent, with the largest range in flood region D. Pseudo coefficients of determination of the generalized least-squares models ranged from 90.29 to 97.28 percent, with the largest range also in flood region D. The regional regression equations apply only to locations on streams in Arkansas where annual peak discharges are not substantially affected by regulation, diversion, channelization, backwater, or urbanization. The applicability and accuracy of the regional regression equations depend on the basin characteristics measured for an ungaged location on a stream being within range of those

  10. Ecological response to hydrological variability and catchment development: Insights from a shallow oxbow lake in Lower Mississippi Valley, Arkansas.

    Science.gov (United States)

    Bhattacharya, Ruchi; Hausmann, Sonja; Hubeny, J Bradford; Gell, Peter; Black, Jessica L

    2016-11-01

    The ecological response of shallow oxbow lakes to variability in hydrology and catchment development in large river floodplain ecosystems (RFE) in Arkansas remains largely unknown. Investigating these responses will advance our understanding of ecological evolution of oxbow lakes in response to the major environmental drivers, which will establish baseline conditions required to develop effective management practices for RFE. In this pilot study, we examined the potential of using a dated surface sediment core from Adams Bayou, a floodplain lake located within the Cache-Lower White River Ramsar site in SE Arkansas. Stratigraphic records of diatoms and sediment geochemistry were used to ascertain variation in Adams Bayou's ecological condition. During 1968-2008, in response to hydrological and anthropogenic changes, Adams Bayou's diatom assemblages progressed from predominantly benthic (Gomphonema parvulum and Meridion circulare) to primarily planktonic assemblage (Aulacoseira granulata and Cyclotella meneghiniana), along with a decrease in magnetic susceptibility (k) and % silt. Statistical analyses reveled that during 1968-2000, higher hydrological connectivity and catchment alterations drove Adams Bayou's ecosystem. After 2000, lower hydrological connectivity and increase in cultivation were the major drivers. The potential impact of increasing air temperature was also noted. The shift in Adams Bayou from a connected, clear, mesotrophic state to a relatively isolated, turbid and nutrient enriched state is consistent with regime shift models and highlights its sensitivity to a combination of environmental stresses prevalent in the catchment. Although fluvial systems pose challenges in establishing clear chronologies, oxbow lake sediments can be a effective paleoecological archives. Our work provides clear evidence for the change in the ecological character of this wetland of international significance and flags the need for a wider assessment of water bodies

  11. Analysis and inundation mapping of the April-May 2011 flood at selected locations in northern and eastern Arkansas and southern Missouri

    Science.gov (United States)

    Westerman, Drew A.; Merriman, Katherine R.; De Lanois, Jeanne L.; Berenbrock, Charles

    2013-01-01

    Precipitation that fell from April 19 through May 3, 2011, resulted in widespread flooding across northern and eastern Arkansas and southern Missouri. The first storm produced a total of approximately 16 inches of precipitation over an 8-day period, and the following storms produced as much as 12 inches of precipitation over a 2-day period. Moderate to major flooding occurred quickly along many streams within Arkansas and Missouri (including the Black, Cache, Illinois, St. Francis, and White Rivers) at levels that had not been seen since the historic 1927 floods. The 2011 flood claimed an estimated 21 lives in Arkansas and Missouri, and damage caused by the flooding resulted in a Federal Disaster Declaration for 59 Arkansas counties that received Federal or State assistance. To further the goal of documenting and understanding floods, the U.S. Geological Survey, in cooperation with the Federal Emergency Management Agency, the U.S. Army Corps of Engineers–Little Rock and Memphis Districts, and Arkansas Natural Resources Commission, conducted a study to summarize meteorological and hydrological conditions before the flood; computed flood-peak magnitudes for 39 streamgages; estimated annual exceedance probabilities for 37 of those streamgages; determined the joint probabilities for 11 streamgages paired to the Mississippi River at Helena, Arkansas, which refers to the probability that locations on two paired streams simultaneously experience floods of a magnitude greater than or equal to a given annual exceedance probability; collected high-water marks; constructed flood-peak inundation maps showing maximum flood extent and water depths; and summarized flood damages and effects. For the period of record used in this report, peak-of-record stage occurred at 24 of the 39 streamgages, and peak-of-record streamflow occurred at 13 of the 30 streamgages where streamflow was determined. Annual exceedance probabilities were estimated to be less than 0.5 percent at three

  12. Risk prevention during reactor shutdown

    International Nuclear Information System (INIS)

    During reactor shutdown potential risks are issued of a number of maintenance operations. In this text we analyse these operations and give the modifications of technical specifications to ameliorate the reactor safety. 4 figs

  13. Power calibrations for TRIGA reactors

    International Nuclear Information System (INIS)

    The purpose of this paper is to establish a framework for the calorimetric power calibration of TRIGA reactors so that reliable results can be obtained with a precision better than ± 5%. Careful application of the same procedures has produced power calibration results that have been reproducible to ± 1.5%. The procedures are equally applicable to the Mark I, Mark II and Mark III reactors as well as to reactors having much larger reactor tanks and to TRIGA reactors capable of forced cooling up to 3 MW in some cases and 15 MW in another case. In the case of forced cooled TRIGA reactors, the calorimetric power calibration is applicable in the natural convection mode for these reactors using exactly the same procedures as are discussed below for the smaller TRIGA reactors (< 2 MW)

  14. Reactor Engineering Department annual report

    International Nuclear Information System (INIS)

    Research and development activities in the Department of Reactor Engineering in fiscal 1982 are described. The work of the Department is closely related to development of multipurpose Very High Temperature Gas Cooled Reactor and Fusion Reactor, and development of Liquid Metal Fast Breeder Reactor carried out by Power Reactor and Nuclear Fuel Development Corporation. Since fiscal 1982, Systematic research and development work on safeguards technology has been added to the activities of the Department. Contents of the report are achievements in fields such as nuclear data and group constants, theoretical method and code development, integral experiment and analysis, fusion neutronics, shielding, reactor and nuclear instrumentation, reactor control and diagnosis, and safeguards technology, and activities of the Committee on Reactor Physics. (author)

  15. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    The Operating Reactors Licensing Actions Summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors

  16. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  17. High Flux Isotope Reactor (HFIR)

    Data.gov (United States)

    Federal Laboratory Consortium — The HFIR at Oak Ridge National Laboratory is a light-water cooled and moderated reactor that is the United States’ highest flux reactor-based neutron source. HFIR...

  18. Reactor operation safety information document

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  19. Reactor safety in Eastern Europe

    International Nuclear Information System (INIS)

    The papers presented to the GRS colloquium refer to the cooperative activities for reactor accident analysis and modification of the GRS computer codes for their application to reactors of the Russian design types of WWER or RBMK. Another topic is the safety of RBMK reactors in particular, and the current status of investigations and studies addressing the containment of unit 4 of the Chernobyl reactor station. All papers are indexed separately in report GRS--117. (HP)

  20. Fast reactor programme

    International Nuclear Information System (INIS)

    This progress report summarizes the fast reactor research carried out by ECN during the period covering the year 1980. This research is mainly concerned with the cores of sodium-cooled breeders, in particular the SNR-300, and its related safety aspects. It comprises six items: A programme to determine relevant nuclear data of fission- and corrosion-products; A fuel performance programme comprising in-pile cladding failure experiments and a study of the consequences of loss-of-cooling and overpower; Basic research on fuel; Investigation of the changes in the mechanical properties of austenitic stainless steel DIN 1.4948 due to fast neutron doses, this material has been used in the manufacture of the reactor vessel and its internal components; Study of aerosols which could be formed at the time of a fast reactor accident and their progressive behaviour on leaking through cracks in the concrete containment; Studies on heat transfer in a sodium-cooled fast reactor core. As fast breeders operate at high power densities, an accurate knowledge of the heat transfer phenomena under single-phase and two-phase conditions is sought. (Auth.)

  1. Thermal Reactor Safety

    International Nuclear Information System (INIS)

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods

  2. NEUTRONIC REACTOR FUEL ELEMENT

    Science.gov (United States)

    Picklesimer, M.L.; Thurber, W.C.

    1961-01-01

    A chemically nonreactive fuel composition for incorporation in aluminum- clad, plate type fuel elements for neutronic reactors is described. The composition comprises a mixture of aluminum and uranium carbide particles, the uranium carbide particles containing at least 80 wt.% UC/sub 2/.

  3. Stabilized Spheromak Fusion Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, T

    2007-04-03

    The U.S. fusion energy program is focused on research with the potential for studying plasmas at thermonuclear temperatures, currently epitomized by the tokamak-based International Thermonuclear Experimental Reactor (ITER) but also continuing exploratory work on other plasma confinement concepts. Among the latter is the spheromak pursued on the SSPX facility at LLNL. Experiments in SSPX using electrostatic current drive by coaxial guns have now demonstrated stable spheromaks with good heat confinement, if the plasma is maintained near a Taylor state, but the anticipated high current amplification by gun injection has not yet been achieved. In future experiments and reactors, creating and maintaining a stable spheromak configuration at high magnetic field strength may require auxiliary current drive using neutral beams or RF power. Here we show that neutral beam current drive soon to be explored on SSPX could yield a compact spheromak reactor with current drive efficiency comparable to that of steady state tokamaks. Thus, while more will be learned about electrostatic current drive in coming months, results already achieved in SSPX could point to a productive parallel development path pursuing auxiliary current drive, consistent with plans to install neutral beams on SSPX in the near future. Among possible outcomes, spheromak research could also yield pulsed fusion reactors at lower capital cost than any fusion concept yet proposed.

  4. Reactors. Nuclear propulsion ships

    International Nuclear Information System (INIS)

    This article has for object the development of nuclear-powered ships and the conception of the nuclear-powered ship. The technology of the naval propulsion P.W.R. type reactor is described in the article B.N.3 141 'Nuclear Boilers ships'. (N.C.)

  5. Pressure tube type reactor

    International Nuclear Information System (INIS)

    Heretofore, a pressure tube type reactor has a problem in that the evaluation for the reactor core performance is complicate and no sufficient consideration is made for the economical property, to increase the size of a calandria tank and make the cost expensive. Then, in the present invention, the inner diameter of a pressure tube is set to greater than 50% of the lattice gap in a square lattice like arrangement, and the difference between the inner and the outer diameters of the calandria tube is set smaller than 20% of the lattice gap. Further, the inner diameter of the pressure tube is set to greater than 40% and the difference between the inner and the outer diameters of the calandria tube is set smaller than 30% of the lattice gap in a triangle lattice arrangement. Then, heavy water-to-fuel volume ratio can be determined appropriately and the value for the coolant void coefficient is made more negative side, to improve the self controllability inherent to the reactor. In particular, when 72 to 90 fuel rods are arranged per one pressure tube, the power density per one fuel rod is can be increased by about twice. Accordingly, the number of the pressure tubes can be reduced about to one-half, thereby enabling to remarkably decrease the diameter of the reactor core and to reduce the size of the calandria, which is economical. (N.H.)

  6. Fusion reactor materials

    International Nuclear Information System (INIS)

    At the Belgian Nuclear Research Centre SCK-CEN, activities related to fusion focus on environmental tolerance of opto-electronic components. The objective of this program is to contribute to the knowledge on the behaviour, during and after neutron irradiation, of fusion-reactor materials and components. The main scientific activities for 1997 are summarized

  7. Integral Fast Reactor Program

    International Nuclear Information System (INIS)

    This report summarizes highlights of the technical progress made in the Integral Fast Reactor (IFR) Program in FY 1992. Technical accomplishments are presented in the following areas of the IFR technology development activities: (1) metal fuel performance, (2) pyroprocess development, (3) safety experiments and analyses, (4) core design development, (5) fuel cycle demonstration, and (6) LMR technology R ampersand D

  8. Nuclear reactor building

    Science.gov (United States)

    Gou, Perng-Fei; Townsend, Harold E.; Barbanti, Giancarlo

    1994-01-01

    A reactor building for enclosing a nuclear reactor includes a containment vessel having a wetwell disposed therein. The wetwell includes inner and outer walls, a floor, and a roof defining a wetwell pool and a suppression chamber disposed thereabove. The wetwell and containment vessel define a drywell surrounding the reactor. A plurality of vents are disposed in the wetwell pool in flow communication with the drywell for channeling into the wetwell pool steam released in the drywell from the reactor during a LOCA for example, for condensing the steam. A shell is disposed inside the wetwell and extends into the wetwell pool to define a dry gap devoid of wetwell water and disposed in flow communication with the suppression chamber. In a preferred embodiment, the wetwell roof is in the form of a slab disposed on spaced apart support beams which define therebetween an auxiliary chamber. The dry gap, and additionally the auxiliary chamber, provide increased volume to the suppression chamber for improving pressure margin.

  9. Studies on reactor physics

    International Nuclear Information System (INIS)

    Most of the peaceful applications of atomic energy are inherently dependent on advances in the science and technology of nuclear reactors, and aspects of this development are part of a major programme of the International Atomic Energy Agency. The most useful role that the Agency can play is as a co-ordinating body or central forum where the trends can be reviewed and the results assessed. Some of the basic studies are carried out by members of the Agency's own scientific staff. The Agency also convenes groups of experts from different countries to examine a particular problem in detail and make any necessary recommendations. Some of the important subjects are discussed at international scientific meetings held by the Agency. One of the subjects covered by such studies is the physics of nuclear reactors and a specific topic recently discussed was Codes for Reactor Computations, on which a seminar was held in Vienna in April this year. Another The members of the Panel described the development of heavy water reactors, the equipment and methods of research currently used, and plans for further development in their respective countries meeting of Panel of Experts on Heavy Water Lattices was held in Vienna in August 1959

  10. Nuclear power reactor physics

    International Nuclear Information System (INIS)

    The purpose of this book is to explain the physical working conditions of nuclear reactors for the benefit of non-specialized engineers and engineering students. One of the leading ideas of this course is to distinguish between two fundamentally different concepts: - a science which could be called neutrodynamics (as distinct from neutron physics which covers the knowledge of the neutron considered as an elementary particle and the study of its interactions with nuclei); the aim of this science is to study the interaction of the neutron gas with real material media; the introduction will however be restricted to its simplified expression, the theory and equation of diffusion; - a special application: reactor physics, which is introduced when the diffusing and absorbing material medium is also multiplying. For this reason the chapter on fission is used to introduce this section. In practice the section on reactor physics is much longer than that devoted to neutrodynamics and it is developed in what seemed to be the most relevant direction: nuclear power reactors. Every effort was made to meet the following three requirements: to define the physical bases of neutron interaction with different materials, to give a correct mathematical treatment within the limit of necessary simplifying hypotheses clearly explained; to propose, whenever possible, numerical applications in order to fix orders of magnitude

  11. Cermet fuel reactors

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, C.L.; Palmer, R.S.; Van Hoomissen, J.E.; Bhattacharyya, S.K.; Barner, J.O.

    1987-09-01

    Cermet fueled nuclear reactors are attractive candidates for high performance space power systems. The cermet fuel consists of tungsten-urania hexagonal fuel blocks characterized by high strength at elevated temperatures, a high thermal conductivity and resultant high thermal shock resistance. Key features of the cermet fueled reactor design are (1) the ability to achieve very high coolant exit temperatures, and (2) thermal shock resistance during rapid power changes, and (3) two barriers to fission product release - the cermet matrix and the fuel element cladding. Additionally, thre is a potential for achieving a long operating life because of (1) the neutronic insensitivity of the fast-spectrum core to the buildup of fission products and (2) the utilization of a high strength refractory metal matrix and structural materials. These materials also provide resistance against compression forces that potentially might compact and/or reconfigure the core. In addition, the neutronic properties of the refractory materials assure that the reactor remains substantially subcritical under conditions of water immersion. It is concluded that cermet fueled reactors can be utilized to meet the power requirements for a broad range of advanced space applications. 4 refs., 4 figs., 3 tabs.

  12. Cermet fuel reactors

    International Nuclear Information System (INIS)

    Cermet fueled nuclear reactors are attractive candidates for high performance space power systems. The cermet fuel consists of tungsten-urania hexagonal fuel blocks characterized by high strength at elevated temperatures, a high thermal conductivity and resultant high thermal shock resistance. Key features of the cermet fueled reactor design are (1) the ability to achieve very high coolant exit temperatures, and (2) thermal shock resistance during rapid power changes, and (3) two barriers to fission product release - the cermet matrix and the fuel element cladding. Additionally, thre is a potential for achieving a long operating life because of (1) the neutronic insensitivity of the fast-spectrum core to the buildup of fission products and (2) the utilization of a high strength refractory metal matrix and structural materials. These materials also provide resistance against compression forces that potentially might compact and/or reconfigure the core. In addition, the neutronic properties of the refractory materials assure that the reactor remains substantially subcritical under conditions of water immersion. It is concluded that cermet fueled reactors can be utilized to meet the power requirements for a broad range of advanced space applications. 4 refs., 4 figs., 3 tabs

  13. The Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The documentation abstracted contains a complete survey of the broadcasts transmitted by the Russian wire service of the Deutsche Welle radio station between April 28 and Mai 15, 1986 on the occasion of the Chernobyl reactor accident. Access is given to extracts of the remarkable eastern and western echoes on the broadcasts of the Deutsche Welle. (HP)

  14. SRP reactor safety evolution

    International Nuclear Information System (INIS)

    The Savannah River Plant reactors have operated for over 100 reactor years without an incident of significant consequence to on or off-site personnel. The reactor safety posture incorporates a conservative, failure-tolerant design; extensive administrative controls carried out through detailed operating and emergency written procedures; and multiple engineered safety systems backed by comprehensive safety analyses, adapting through the years as operating experience, changes in reactor operational modes, equipment modernization, and experience in the nuclear power industry suggested. Independent technical reviews and audits as well as a strong organizational structure also contribute to the defense-in-depth safety posture. A complete review of safety history would discuss all of the above contributors and the interplay of roles. This report, however, is limited to evolution of the engineered safety features and some of the supporting analyses. The discussion of safety history is divided into finite periods of operating history for preservation of historical perspective and ease of understanding by the reader. Programs in progress are also included. The accident at Three Mile Island was assessed for its safety implications to SRP operation. Resulting recommendations and their current status are discussed separately at the end of the report. 16 refs., 3 figs

  15. Fusion reactor materials

    International Nuclear Information System (INIS)

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics

  16. Thermal Reactor Safety

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

  17. Department of reactor technology

    International Nuclear Information System (INIS)

    The activities of the Department of Reactor Technology at Risoe during 1980 are described. The work is presented in three chapters: General Information on the Department, Summary of the Department's Development during 1980, and Activities of the Department. Lists of staff, publications, computer programs, and test facilities are included. (author)

  18. The AP1000 reactor

    International Nuclear Information System (INIS)

    The design of the AP1000 reactor began 20 years ago when Westinghouse launched the AP600 reactor project. In fact by re-assessing AP600's safety margins Westinghouse realized that the its power output could be raised without putting at risk its safety standard. The AP1000 was born, it yields 1100 MWe. The main AP1000's design features is its passive safety (particularly after the Fukushima accident) and its modularity. The passive safety of the AP1000 implies: -) no humane intervention needed for 72 hours at least after the incident; -) no necessity for redundant complex safety systems. The modularity means that the plant, the reactor and other buildings are constructed from a choice of 300 modular units. These units can be built off-site and fit together on site. The modularity allows more construction activities to be led simultaneously and more chances to cope with the construction schedule. The NRC has approved the operation license for 30 years of the first AP1000 being built in the Usa (Vogtle plant in Georgia). 4 AP1000 are being built in China (Sanmen and Haiyang sites) and 6 others are planned in the Usa. Westinghouse is convinced that the AP1000's passive safety makes it more attractive. Let us not forget that Westinghouse was at the origin of the concept of pressurized water reactors, an idea adopted for half the nuclear power stations in the world and for all the plants now active in France. (A.C.)

  19. Fast reactor programme

    International Nuclear Information System (INIS)

    This progress report summarises the fast reactor research carried out at the Netherlands Energy Research Centre during the year 1981. The neutron and fission product cross sections of various isotopes have been evaluated. In the fuel performance programme, some preliminary results are given and irradiation facilities described. Creep experiments on various stainless steel components are reported

  20. Nuclear rocket engine reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lanin, Anatoly

    2013-07-01

    Covers a new technology of nuclear reactors and the related materials aspects. Integrates physics, materials science and engineering Serves as a basic book for nuclear engineers and nuclear physicists. The development of a nuclear rocket engine reactor (NRER) is presented in this book. The working capacity of an active zone NRER under mechanical and thermal load, intensive neutron fluxes, high energy generation (up to 30 MBT/l) in a working medium (hydrogen) at temperatures up to 3100 K is displayed. Design principles and bearing capacity of reactors area discussed on the basis of simulation experiments and test data of a prototype reactor. Property data of dense constructional, porous thermal insulating and fuel materials like carbide and uranium carbide compounds in the temperatures interval 300 - 3000 K are presented. Technological aspects of strength and thermal strength resistance of materials are considered. The design procedure of possible emergency processes in the NRER is developed and risks for their origination are evaluated. Prospects of the NRER development for pilotless space devices and piloted interplanetary ships are viewed.

  1. Nuclear Reactors and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. [eds.

    1992-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  2. Fusion reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1989-01-01

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  3. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis

  4. Fast reactors: potential for power

    International Nuclear Information System (INIS)

    The subject is discussed as follows: basic facts about conventional and fast reactors; uranium economy; plutonium and fast reactors; cooling systems; sodium coolant; safety engineering; handling and recycling plutonium; safeguards; development of fast reactors in Britain and abroad; future progress. (U.K.)

  5. Reactor physics problems on HCPWR

    International Nuclear Information System (INIS)

    Reactor physics problems on high conversion pressurized water reactors (HCPWRs) are discussed. Described in this report are outline of the HCPWR, expected accuracy for the various reactor physical qualities, and method for K-effective calculation in the resonance energy area. And requested further research problems are shown. The target value of the conversion ratio are also discussed. (author)

  6. Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

    Science.gov (United States)

    Roth, R. J.

    1976-01-01

    The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

  7. Spatio-Temporal Trends of Oak Decline and Mortality under Periodic Regional Drought in the Ozark Highlands of Arkansas and Missouri

    OpenAIRE

    Shifley, Stephen R.; Hong He; W. Keith Moser; Spetich, Martin A.; Michael K. Crosby; Zhaofei Fan; Xiuli Fan

    2012-01-01

    At the forest landscape/region level, based on annual Forest Inventory and Analysis plot data from 1999 to 2010, oak decline and mortality trends for major oak species (groups) were examined in the Ozark Highlands of Arkansas and Missouri. Oak decline has elevated cumulative mortality of red oak species to between 11 and 15 percent in terms of relative density and basal area of standing dead oak trees, respectively. These values are three to five times higher than...

  8. The project for intercomparison of land-surface parameterization schemes (PILPS) phase 2(c) Red-Arkansas River basin experiment: 1. Experiment description and summary intercomparisons

    OpenAIRE

    Wood, EF; Lettenmaier, DP; Liang, X.; D. Lohmann; Boone, A.; Chang, S; Chen, F.; Dai, Y.; Dickinson, RE; Duan, Q; M. Ek; Gusev, YM; Habets, F.; Irannejad, P.; Koster, R

    1998-01-01

    Sixteen land-surface schemes participating in the project for the Intercomparison of Land-surface Schemes (PILPS) Phase 2(c) were run using 10 years (1979-1988) of forcing data for the Red-Arkansas River basins in the Southern Great Plains region of the United States. Forcing data (precipitation, incoming radiation and surface meteorology) and land-surface characteristics (soil and vegetation parameters) were provided to each of the participating schemes. Two groups of runs are presented. (1)...

  9. Reactor vessel support system. [LMFBR

    Science.gov (United States)

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  10. Reactor monitoring using antineutrino detectors

    Science.gov (United States)

    Bowden, N. S.

    2011-08-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactor as part of International Atomic Energy Agency (IAEA) and/or other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway worldwide.

  11. Reactor physics activities in Japan

    International Nuclear Information System (INIS)

    This report reviews the research activity in reactor physics field in Japan during July, 1992 - July, 1993. The review was performed in the following fields : nuclear data evaluation, calculational method development, fast reactor physics, thermal reactor physics, advanced core design, fusion reactor neutronics, nuclear criticality safety, shielding, incineration of radioactive nuclear wastes, noise analysis and control and national programs. The main references were taken from journals and reports published during this period. The research committee of reactor physics is responsible for the review work. (author)

  12. Status of Water Levels and Selected Water-Quality Conditions in the Sparta-Memphis Aquifer in Arkansas and the Status of Water Levels in the Sparta Aquifer in Louisiana, Spring 2005

    Science.gov (United States)

    Schrader, T.P.; Jones, J.S.

    2007-01-01

    The U.S. Geological Survey in cooperation with the Arkansas Natural Resources Commission, the Arkansas Geological Commission, and the Louisiana Department of Transportation and Development has monitored water levels in the Sparta Sand of Claiborne Group and Memphis Sand of Claiborne Group since the 1920's. Ground-water withdrawals have increased while water levels have declined since monitoring was initiated. This report has been produced to describe ground-water levels in the aquifers in the Sparta Sand and Memphis Sand and provide information for the management of this valuable resource. The 2005 potentiometric-surface map of the aquifers in the Sparta Sand and Memphis Sand was constructed using water-level data collected in 333 wells in Arkansas and 120 wells in Louisiana during the spring of 2005. The highest water-level altitude measured in Arkansas was 327 feet above National Geodetic Vertical Datum of 1929 located in Grant County in the outcrop at the western boundary of the study area; the lowest water-level altitude was 189 feet below National Geodetic Vertical Datum of 1929 in Union County. The highest water-level altitude measured in Louisiana was 246 feet above National Geodetic Vertical Datum of 1929 located in Bossier Parish in the outcrop area near the western boundary of the study area; the lowest water-level altitude was 226 feet below National Geodetic Vertical Datum of 1929 in central Ouachita Parish. Three large depressions centered in Columbia, Jefferson, and Union Counties in Arkansas are the result of large withdrawals for industrial and public supplies. In Louisiana, three major pumping centers are in Ouachita, Jackson, and Lincoln Parishes. Water withdrawals from these major pumping centers primarily is used for industrial and public-supply purposes. Withdrawals from Ouachita and Lincoln Parishes and Union County, Arkansas, primarily for industrial purposes, have caused the resulting cones of depression to coalesce so that the -40 foot

  13. Advanced reactor experimental facilities

    International Nuclear Information System (INIS)

    For many years, the NEA has been examining advanced reactor issues and disseminating information of use to regulators, designers and researchers on safety issues and research needed. Following the recommendation of participants at an NEA workshop, a Task Group on Advanced Reactor Experimental Facilities (TAREF) was initiated with the aim of providing an overview of facilities suitable for carrying out the safety research considered necessary for gas-cooled reactors (GCRs) and sodium fast reactors (SFRs), with other reactor systems possibly being considered in a subsequent phase. The TAREF was thus created in 2008 with the following participating countries: Canada, the Czech Republic, Finland, France, Germany, Hungary, Italy, Japan, Korea and the United States. In a second stage, India provided valuable information on its experimental facilities related to SFR safety research. The study method adopted entailed first identifying high-priority safety issues that require research and then categorizing the available facilities in terms of their ability to address the safety issues. For each of the technical areas, the task members agreed on a set of safety issues requiring research and established a ranking with regard to safety relevance (high, medium, low) and the status of knowledge based on the following scale relative to full knowledge: high (100%-75%), medium (75 - 25%) and low (25-0%). Only the issues identified as being of high safety relevance and for which the state of knowledge is low or medium were included in the discussion, as these issues would likely warrant further study. For each of the safety issues, the TAREF members identified appropriate facilities, providing relevant information such as operating conditions (in- or out-of reactor), operating range, description of the test section, type of testing, instrumentation, current status and availability, and uniqueness. Based on the information collected, the task members assessed prospects and priorities

  14. Relations between continuous real-time physical properties and discrete water-quality constituents in the Little Arkansas River, south-central Kansas, 1998-2014

    Science.gov (United States)

    Rasmussen, Patrick P.; Eslick, Patrick J.; Ziegler, Andrew C.

    2016-08-11

    Water from the Little Arkansas River is used as source water for artificial recharge of the Equus Beds aquifer, one of the primary water-supply sources for the city of Wichita, Kansas. The U.S. Geological Survey has operated two continuous real-time water-quality monitoring stations since 1995 on the Little Arkansas River in Kansas. Regression models were developed to establish relations between discretely sampled constituent concentrations and continuously measured physical properties to compute concentrations of those constituents of interest. Site-specific regression models were originally published in 2000 for the near Halstead and near Sedgwick U.S. Geological Survey streamgaging stations and the site-specific regression models were then updated in 2003. This report updates those regression models using discrete and continuous data collected during May 1998 through August 2014. In addition to the constituents listed in the 2003 update, new regression models were developed for total organic carbon. The real-time computations of water-quality concentrations and loads are available at http://nrtwq.usgs.gov. The water-quality information in this report is important to the city of Wichita because water-quality information allows for real-time quantification and characterization of chemicals of concern (including chloride), in addition to nutrients, sediment, bacteria, and atrazine transported in the Little Arkansas River. The water-quality information in this report aids in the decision making for water treatment before artificial recharge.

  15. Simulated response to pumping stress in the Sparta aquifer of southeastern Arkansas and north-central Louisiana, 1998-2027

    Science.gov (United States)

    Hays, Phillip D.; Lovelace, John K.; Reed, Thomas B.

    1998-01-01

    The Sparta aquifer in southeastern Arkansas and north-central Louisiana is a major water resource for municipal, industrial, and agricultural uses. In recent years, the demand for water in some areas has resulted in withdrawals from the Sparta that significantly exceed recharge to the aquifer. Considerable drawdown has occurred in the potentiometric surface, and water users and managers alike have begun to question the ability of the aquifer to supply water for the long term. Large cones of depression are centered beneath the Grand Prairie area and the cities of Pine Bluff and El Dorado in Arkansas, and Monroe in Louisiana. Water levels in the aquifer have declined at rates greater than 1 foot per year for more than a decade in much of southern Arkansas and northern Louisiana and are now below the top of the formation in parts of Union and Columbia Counties, Arkansas, and in several areas of Louisiana. Problems related to over draft in the Sparta could result in increased drilling and pumping costs, loss of yield, salt-water intrusion, and decrease in water quality in areas of large drawdown. The effects of current ground-water withdrawals and potential future withdrawals on water availability are major concerns of water managers and users as well as the general public in the two States. The Sparta model-a regional scale, digital ground-water flow model-was first calibrated in the mid-1980's. The model was updated and reverified using 1995-97 data. Visual inspection of the observed (1996-97) and simulated potentiometric surfaces, statistical analysis of the error for the original calibration and current reverification, and comparison of observed versus simulated hydro graphs indicates that the model is simulating conditions in the aquifer within acceptable error, and the quality of current (1998) model results is similar to the original model calibration results. When stressed with current withdrawal volumes and distributions, the model is able to simulate

  16. Reactor simulator development. Workshop material

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency (IAEA) has established a programme in nuclear reactor simulation computer programs to assist its Member States in education and training. The objective is to provide, for a variety of advanced reactor types, insight and practice in reactor operational characteristics and their response to perturbations and accident situations. To achieve this, the IAEA arranges for the supply or development of simulation programs and training material, sponsors training courses and workshops, and distributes documentation and computer programs. This publication consists of course material for workshops on development of such reactor simulators. Participants in the workshops are provided with instruction and practice in the development of reactor simulation computer codes using a model development system that assembles integrated codes from a selection of pre-programmed and tested sub-components. This provides insight and understanding into the construction and assumptions of the codes that model the design and operational characteristics of various power reactor systems. The main objective is to demonstrate simple nuclear reactor dynamics with hands-on simulation experience. Using one of the modular development systems, CASSIMtm , a simple point kinetic reactor model is developed, followed by a model that simulates the Xenon/Iodine concentration on changes in reactor power. Lastly, an absorber and adjuster control rod, and a liquid zone model are developed to control reactivity. The built model is used to demonstrate reactor behavior in sub-critical, critical and supercritical states, and to observe the impact of malfunctions of various reactivity control mechanisms on reactor dynamics. Using a PHWR simulator, participants practice typical procedures for a reactor startup and approach to criticality. This workshop material consists of an introduction to systems used for developing reactor simulators, an overview of the dynamic simulation

  17. Reactor water spontaneous circulation structure in reactor pressure vessel

    International Nuclear Information System (INIS)

    The gap between the inner wall of a reactor pressure vessel of a BWR type reactor and a reactor core shroud forms a down comer in which reactor water flows downwardly. A feedwater jacket to which feedwater at low temperature is supplied is disposed at the outer circumference of the pressure vessel just below a gas/water separator. The reactor water at the outer circumferential portion just below the air/water separator is cooled by the feedwater jacket, and the feedwater after cooling is supplied to the feedwater entrance disposed below the feedwater jacket by way of a feedwater introduction line to supply the feedwater to the lower portion of the down comer. This can cool the reactor water in the down comer to increase the reactor water density in the down comer thereby forming strong downward flows and promote the recycling of the reactor water as a whole. With such procedures, the reactor water can be recycled stably only by the difference of the specific gravity of the reactor water without using an internal pump. In addition, the increase of the height of the pressure vessel can be suppressed. (I.N.)

  18. Safety review, assessment and inspection on research reactors, experimental reactors, nuclear heating reactors and critical facilities

    International Nuclear Information System (INIS)

    In 1998, the NNSA organized to complete the nuclear safety review on the test loop in-reactor operation of the High-flux Engineering Experimental Reactor (HFEER) and the re-operation of the China Pulsed Reactor and the Uranium-water Criticality Facility. The NNSA conducted the nuclear safety review on the CP application of the China Experimental Fast Reactor (CEFR) and the siting of China Advanced Research Reactor (CARR), and carried out the construction supervision on HTR-10, and dealt with the event about the technological tube breakage of HWRR and other events

  19. Compact fusion reactors

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Fusion research is currently to a large extent focused on tokamak (ITER) and inertial confinement (NIF) research. In addition to these large international or national efforts there are private companies performing fusion research using much smaller devices than ITER or NIF. The attempt to achieve fusion energy production through relatively small and compact devices compared to tokamaks decreases the costs and building time of the reactors and this has allowed some private companies to enter the field, like EMC2, General Fusion, Helion Energy, Lawrenceville Plasma Physics and Lockheed Martin. Some of these companies are trying to demonstrate net energy production within the next few years. If they are successful their next step is to attempt to commercialize their technology. In this presentation an overview of compact fusion reactor concepts is given.

  20. Elk River Reactor dismantling

    International Nuclear Information System (INIS)

    The dismantling program was carried out in three overlapping phases: the planning phase which included the preliminary planning and selection of the dismantling approach, the dismantling phase which included all work performed to remove the reactor facility and restore the site to its pre-reactor condition, and the closeout phase which included the final site survey and efforts necessary to terminate the AEC license and contract. Of particular interest was the use of a remotely operated plasma cutting torch to section the pressure vessel internals, the pressure vessel and the outer thermal shield, the use of explosives in removal of the biological shield and the method of establishment of the criteria for material disposal

  1. REACTOR MODERATOR STRUCTURE

    Science.gov (United States)

    Greenstreet, B.L.

    1963-12-31

    A system for maintaining the alignment of moderator block structures in reactors is presented. Integral restraining grids are placed between each layer of blocks in the moderator structure, at the top of the uppermost layer, and at the bottom of the lowermost layer. Slots are provided in the top and bottom surfaces of the moderator blocks so as to provide a keying action with the grids. The grids are maintained in alignment by vertical guiding members disposed about their peripheries. (AEC)

  2. Fusion Reactor Materials

    International Nuclear Information System (INIS)

    SCK-CEN's programme on fusion reactor materials includes studies (1) to investigate fracture mechanics of neutron-irradiated beryllium; (2) to describe the helium behaviour in irradiated beryllium at atomic scale; (3) to define the kinetics of beryllium reacting with air or steam; (3) to perform a feasibility study for the testing of integrated blanket modules under neutron irradiation. Progress and achievements in 1997 are reported

  3. Decommissioning of research reactors

    International Nuclear Information System (INIS)

    Research reactors of WWR-S type were built in countries under Soviet influence in '60, last century and consequently reached their service life. Decommissioning implies removal of all radioactive components, processing, conditioning and final disposal in full safety of all sources on site of radiological pollution. The WWR-S reactor at Bucuresti-Magurele was put into function in 1957 and operated until 1997 when it was stopped and put into conservation in view of decommissioning. Presented are three decommissioning variants: 1. Reactor shut-down for a long period (30-50 years) what would entail a substantial decrease of contamination with lower costs in dismantling, mechanical, chemical and physical processing followed by final disposal of the radioactive wastes. The drawback of this solution is the life prolongation of a non-productive nuclear unit requiring funds for personnel, control, maintenance, etc; 2. Decommissioning in a single stage what implies large funds for a immediate investment; 3. Extending the operation on a series of stages rather phased in time to allow a more convenient flow of funds and also to gather technical solutions, better than the present ones. This latter option seems to be optimal for the case of the WWR-S Research at Bucharest-Magurele Reactor. Equipment and technologies should be developed in order to ensure the technical background of the first operations of decommissioning: equipment for scarification, dismantling, dismemberment in a highly radioactive environment; cutting-to-pieces and disassembling technologies; decontamination modern technologies. Concomitantly, nuclear safety and quality assurance regulations and programmes, specific to decommissioning projects should be implemented, as well as a modern, coherent and reliable system of data acquisition, recording and storing. Also the impact of decommissioning must be thoroughly evaluated. The national team of specialists will be assisted by IAEA experts to ensure the

  4. Nuclear reactor container

    International Nuclear Information System (INIS)

    Upon reactor accident, hydrogen and oxygen are generated by water-zirconium reaction and radiolysis of water, which are accumulated in the reactor. If the concentration of hydrogen and oxygen exceeds a burning limit, there is a possibility of hydrogen burning to cause a danger of deteriorating the integrity of the reactor container and the equipments therein. The limit for the occurrence of the detonation is determined by a relationship between the scale of a detonation cell and the size of the container, and if the scale is greater than the container, the detonation does not occur. The scale of the cell is determined by a gas combustion rate and, if the combustion reaction is suppressed, detonation does not occur even in a large container. Then, an appropriate diluent is added to increase heat capacity of a gas mixture to thereby suppress the temperature elevation of the gas. Incombustible gases having a great heat capacity are preferred for the diluent, and CO2 is used. As the concentration of the CO2 gas to be added is increased, the detonation cell is made greater. Thus, occurrence of detonation due to combustion of the accumulated hydrogen can be prevented. (N.H.)

  5. Towards nuclear fusion reactors

    International Nuclear Information System (INIS)

    In the middle of 21st century, the population on the earth is expected to double, and the energy that mankind consumes to triple. The nuclear fusion which is said the ultimate energy source for mankind is expected to solve this energy problem. As for fusion reactors, fuel materials exist inexhaustibly, distributing evenly, they have high safety in principle, the product of burning is harmless nonradioactive substance that does not require the treatment and disposal, and the attenuation of induced radioactivity due to neutrons is quick and the effect to global environment is little. The basic plan of second stage nuclear fusion research and development was decided in 1975, aiming at attaining the critical plasma condition. JT-60 has attained it in 1987. The project of international thermonuclear fusion experimental reactor (ITER) was started, and the conceptual design was carried out. Under such background, the third stage basic plan was decided in 1992, and its objective is self ignition condition, long time burning and the basis of the reactor engineering technology. The engineering design of the ITER is investigated. (K.I.)

  6. High temperature gas reactor

    International Nuclear Information System (INIS)

    The present invention provides a reflector block structure of a high temperature gas reactor in which graphite blocks are not failed even a containing cylinder loaded to a fuel exchanger collides against to secured reflectors upon loading and withdrawing fuel constitutional elements. Namely, a protection plate made of a metal material such as stainless steel is covered on the secured reflector blocks disposed to the upper most step among secured graphite reflector blocks constituting the reactor core. In addition, positioning guide grooves are formed on the protection plate for guiding the containing cylinder loaded to the fuel exchanger to the column of the reactor core constitutional elements. With such a constitution, even if the containing cylinder of fuel exchanger is hoisted down and collided against the inner circumferential edge of the secured reflector blocks due to deviation of the position and the direction upon exchange of fuels, the reflector blocks are not failed since the above-mentioned portion is covered with the metal protection plate. In addition, the positioning guide grooves lead the fuel exchanger to a predetermined column correctly. (I.S.)

  7. BWR type reactor

    International Nuclear Information System (INIS)

    In a coolant circulation in BWR type reactors, since the mixed stream of steam fluid undergoes a great resistance, the pressure loss due to the flow rate distribution when the coolants flow from the upper plenum into the stand pipe is increased upon passing stand pipe. Also in the spontaneous recycling reactor, pressure loss is still left upon passing the swirling blade of a gas-liquid separator. In view of the above, a plurality of vertical members each having a lower end opened to a gas-liquid two phase boundary and an upper end directly suspended from a steam dryer to the gas-liquid separator. The liquid droplets from the 2-phase boundary heated in the reactor core and formed into a mixed gas-liquid 2-phase stream is directed in the vertical direction accompanied with the steam. The liquid droplets spontaneously fallen by gravity from greater ones successively and the droplets in the steam abutted against the vertical member are fallen as a liquid membrane. Thus, the gas-liquid separation is conducted, the dry steam is directly flown into the steam dryer, thereby capable of providing a gas-liquid separator having gas-liquid separation performance with lower loss than usual. (N.H.)

  8. Licensed operating reactors

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission's monthly LICENSED OPERATING REACTORS Status Summary Report provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management, from the Headquarters Staff of NRC's Office of Inspection and Enforcement, from NRC's Regional Offices, and from utilities. Since all of the data concerning operation of the units is provided by the utility operators less than two weeks after the end of the month, necessary corrections to published information are shown on the ERRATA page. This report is divided into three sections: the first contains monthly highlights and statistics for commercial operating units, and errata from previously reported data; the second is a compilation of detailed information on each unit, provided by NRC Regional Offices, IE Headquarters and the Utilities; and the third section is an appendix for miscellaneous information such as spent fuel storage capability, reactor years of experience and non-power reactors in the United States

  9. Fusion reactor safety

    International Nuclear Information System (INIS)

    Nuclear fusion could soon become a viable energy source. Work in plasma physics, fusion technology and fusion safety is progressing rapidly in a number of Member States and international collaboration continues on work aiming at the demonstration of fusion power generation. Safety of fusion reactors and technological and radiological aspects of waste management are important aspects in the development and design of fusion machines. In order to provide an international forum to review and discuss the status and the progress made since 1983 in programmes related to operational safety aspects of fusion reactors, their waste management and decommissioning concepts, the IAEA had organized the Technical Committee on ''Fusion Reactor Safety'' in Culham, 3-7 November 1986. All presentations of this meeting were divided into four sessions: 1. Statements on National-International Fusion Safety Programmes (5 papers); 2. Operation and System Safety (15 papers); 3. Waste Management and Decommissioning (5 papers); 4. Environmental Impacts (6 papers). A separate abstract was prepared for each of these 31 papers. Refs, figs, tabs

  10. Licensed operating reactors

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission's monthly LICENSED OPERATING REACTORS Status Summary Report provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management, from the Headquarters Staff of NRC's Office of Inspection and Enforcement, from NRC's Regional Offices, and from utilities. Since all of the data concerning operation of the units are provided by the utility operators less than two weeks after the end of the month, necessary corrections to published information are shown on the ERRATA page. This report is divided into three sections: the first contains monthly highlights and statistics for commercial operating units, and errata from previously reported data; the second is a compilation of detailed information on each unit, provided by NRC Regional Offices, IE Headquarters and the Utilities; and the third section is an appendix for miscellaneous information such as spent fuel storage capability, reactor years of experience and non-power reactors in the United States

  11. OECD Halden Reactor Project

    International Nuclear Information System (INIS)

    The OECD Halden Reactor project is an agreement between OECD member countries. It was first signed in 1958 and since then regularly renewed every third year. The activities at the Project is centred around the Halden heavy water rector, the HBWR. The reseach programme comprizes studies of fuel performance under various operating conditions, and the application of computers for process control. The HBWR is equipped for exposing fuel rods to temperatures and pressures, and at heat ratings met in modern BWR's and PWR's. A range of in-core instruments are available, permitting detailed measurements of the reactions of the fuel, including mechanical deformations, thermal behaviour, fission gas release, and corrosion. In the area of computer application, the studies of the communication between operator and process, and the surveillance and control of the reactor core, are of particular interst for reactor operation. 1988 represents the 30th year since the Project was started, and this publication is produced to mark this event. It gives and account of the activities and achievements of the Project through the years 1958-1988

  12. Nutrient Concentrations, Loads, and Yields in the Eucha-Spavinaw Basin, Arkansas and Oklahoma, 2002-2006

    Science.gov (United States)

    Tortorelli, Robert L.

    2008-01-01

    The City of Tulsa, Oklahoma, uses Lake Eucha and Spavinaw Lake in the Eucha-Spavinaw basin in northwestern Arkansas and northeastern Oklahoma for public water supply. Taste and odor problems in the water attributable to blue-green algae have increased in frequency. Changes in the algae community in the lakes may be attributable to increases in nutrient levels in the lakes, and in the waters feeding the lakes. The U.S. Geological Survey, in cooperation with the City of Tulsa, investigated and summarized nitrogen and phosphorus concentrations and provided estimates of nitrogen and phosphorus loads, yields, and flow-weighted concentrations in the Eucha-Spavinaw basin for three 3-year periods - 2002-2004, 2003-2005, and 2004-2006, to update a previous report that used data from water-quality samples for a 3-year period from January 2002 through December 2004. This report provides information needed to advance knowledge of the regional hydrologic system and understanding of hydrologic processes, and provides hydrologic data and results useful to multiple agencies for interstate agreements. Nitrogen and phosphorus concentrations were significantly greater in runoff samples than in base-flow samples for all three periods at Spavinaw Creek near Maysville, Arkansas; Spavinaw Creek near Colcord, Oklahoma, and Beaty Creek near Jay, Oklahoma. Runoff concentrations were not significantly greater than base-flow concentrations at Spavinaw Creek near Cherokee, Arkansas; and Spavinaw Creek near Sycamore, Oklahoma except for phosphorus during 2003-2005. Nitrogen concentrations in base-flow samples significantly increased downstream in Spavinaw Creek from the Maysville to Sycamore stations then significantly decreased from the Sycamore to the Colcord stations for all three periods. Nitrogen in base-flow samples from Beaty Creek was significantly less than in samples from Spavinaw Creek. Phosphorus concentrations in base-flow samples significantly increased from the Maysville to

  13. Sediment Quality and Comparison to Historical Water Quality, Little Arkansas River Basin, South-Central Kansas, 2007

    Science.gov (United States)

    Juracek, Kyle E.; Rasmussen, Patrick P.

    2008-01-01

    The spatial and temporal variability in streambed-sediment quality and its relation to historical water quality was assessed to provide guidance for the development of total maximum daily loads and the implementation of best-management practices in the Little Arkansas River Basin, south-central Kansas. Streambed-sediment samples were collected at 26 sites in 2007, sieved to isolate the less than 63-micron fraction (that is, the silt and clay), and analyzed for selected nutrients (total nitrogen and total phosphorus), organic and total carbon, 25 trace elements, and the radionuclides beryllium-7, cesium-137, lead-210, and radium-226. At eight sites, streambed-sediment samples also were collected and analyzed for bacteria. Particulate nitrogen, phosphorus, and organic carbon concentrations in the streambed sediment varied substantially spatially and temporally, and positive correlations among the three constituents were statistically significant. Along the main-stem Little Arkansas River, streambed-sediment concentrations of particulate nitrogen and phosphorus generally were larger at and downstream from Alta Mills, Kansas. The largest particulate nitrogen concentrations were measured in samples collected in the Emma Creek subbasin and may be related to livestock and poultry production. The largest particulate phosphorus concentrations in the basin were measured in samples collected along the main-stem Little Arkansas River downstream from Alta Mills, Kansas. Particulate nitrogen, phosphorus, and organic carbon content in the water and streambed-sediment samples typically decreased as streamflow increased. This inverse relation may be caused by an increased contribution of sediment from channel-bank sources during high flows and (or) increased particle sizes transported by the high flows. Trace element concentrations in the streambed sediment varied from site to site and typically were less than threshold-effects guidelines for possible adverse biological effects

  14. Nuclear research reactors in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Cota, Anna Paula Leite; Mesquita, Amir Zacarias, E-mail: aplc@cdtn.b, E-mail: amir@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The rising concerns about global warming and energy security have spurred a revival of interest in nuclear energy, giving birth to a 'nuclear power renaissance' in several countries in the world. Particularly in Brazil, in the recent years, the nuclear power renaissance can be seen in the actions that comprise its nuclear program, summarily the increase of the investments in nuclear research institutes and the government target to design and build the Brazilian Multipurpose research Reactor (BMR). In the last 50 years, Brazilian research reactors have been used for training, for producing radioisotopes to meet demands in industry and nuclear medicine, for miscellaneous irradiation services and for academic research. Moreover, the research reactors are used as laboratories to develop technologies in power reactors, which are evaluated today at around 450 worldwide. In this application, those reactors become more viable in relation to power reactors by the lowest cost, by the operation at low temperatures and, furthermore, by lower demand for nuclear fuel. In Brazil, four research reactors were installed: the IEA-R1 and the MB-01 reactors, both at the Instituto de Pesquisas Energeticas Nucleares (IPEN, Sao Paulo); the Argonauta, at the Instituto de Engenharia Nuclear (IEN, Rio de Janeiro) and the IPR-R1 TRIGA reactor, at the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN, Belo Horizonte). The present paper intends to enumerate the characteristics of these reactors, their utilization and current academic research. Therefore, through this paper, we intend to collaborate on the BMR project. (author)

  15. Chernobyl reactor transient simulation study

    International Nuclear Information System (INIS)

    This paper deals with the Chernobyl nuclear power station transient simulation study. The Chernobyl (RBMK) reactor is a graphite moderated pressure tube type reactor. It is cooled by circulating light water that boils in the upper parts of vertical pressure tubes to produce steam. At equilibrium fuel irradiation, the RBMK reactor has a positive void reactivity coefficient. However, the fuel temperature coefficient is negative and the net effect of a power change depends upon the power level. Under normal operating conditions the net effect (power coefficient) is negative at full power and becomes positive under certain transient conditions. A series of dynamic performance transient analysis for RBMK reactor, pressurized water reactor (PWR) and fast breeder reactor (FBR) have been performed using digital simulator codes, the purpose of this transient study is to show that an accident of Chernobyl's severity does not occur in PWR or FBR nuclear power reactors. This appears from the study of the inherent, stability of RBMK, PWR and FBR under certain transient conditions. This inherent stability is related to the effect of the feed back reactivity. The power distribution stability in the graphite RBMK reactor is difficult to maintain throughout its entire life, so the reactor has an inherent instability. PWR has larger negative temperature coefficient of reactivity, therefore, the PWR by itself has a large amount of natural stability, so PWR is inherently safe. FBR has positive sodium expansion coefficient, therefore it has insufficient stability it has been concluded that PWR has safe operation than FBR and RBMK reactors

  16. Comparing the 2000 and 2005 factors affecting the selling price of feeder cattle sold at Arkansas livestock auctions.

    Science.gov (United States)

    Troxel, T R; Barham, B L

    2007-12-01

    The objectives of the study were to determine how factors affecting the selling price of feeder calves changed from 2000 to 2005 and to examine the perception that discounts narrow or even disappear as calf supplies decrease and selling prices increase. Data from weekly Arkansas livestock auctions were collected from January 1 to December 31 in 2000 and 2005. Data included calf sex, breed type, color, muscle score, horn status, frame score, fill, condition, health, and BW. Mean selling prices for 2000 and 2005 were $92.91 +/- 15.05 and $118.32 +/- 15.13 (mean +/- SD; $/45.45 kg), respectively. Individual price observations were subtracted from the respective annual means and became the dependent variable. The selling prices for feeder calves sold in groups of 2 to 5 calves and in groups of >/= 6 calves were greater in 2005 than 2000 (P Brahman (P Brahman Cross, Charolais, Charolais x Limousin, Hereford x Limousin, Limousin, Limousin x one-fourth Brahman, Longhorn, Saler and Simmental. Yellow-white face, black-white face, black, and gray feeder calves received an increase in selling price from 2000 to 2005 (P < 0.001). Although fewer horned feeder calves were sold in 2005 (P < 0.01), they received greater discounts in 2005 than 2000 (-$2.86 +/- 0.16 and -$0.51 +/- 0.09; P < 0.001). In 2005, large-framed feeder calves did not receive the premium detected in 2000, but medium-framed feeder calves in 2005 received a greater selling price compared with 2000. Feeder calves with a muscle score of 1 received a greater premium in 2005 compared with 2000 ($2.58 +/- 0.06 and $0.02 +/- 0.09, respectively; P < 0.001). Feeder calves with a muscle score of 2 were discounted in both years, but the discount in 2005 was not as great as in 2000 (P < 0.001). Full and tanked feeder calves received greater discounts in 2005 than in 2000 (P < 0.001). Discounts for fleshy and fat feeder calves were greater in 2005 than in 2000. Most factors affecting the selling price of Arkansas feeder

  17. Comparing the 2000 and 2005 factors affecting the selling price of feeder cattle sold at Arkansas livestock auctions.

    Science.gov (United States)

    Troxel, T R; Barham, B L

    2007-12-01

    The objectives of the study were to determine how factors affecting the selling price of feeder calves changed from 2000 to 2005 and to examine the perception that discounts narrow or even disappear as calf supplies decrease and selling prices increase. Data from weekly Arkansas livestock auctions were collected from January 1 to December 31 in 2000 and 2005. Data included calf sex, breed type, color, muscle score, horn status, frame score, fill, condition, health, and BW. Mean selling prices for 2000 and 2005 were $92.91 +/- 15.05 and $118.32 +/- 15.13 (mean +/- SD; $/45.45 kg), respectively. Individual price observations were subtracted from the respective annual means and became the dependent variable. The selling prices for feeder calves sold in groups of 2 to 5 calves and in groups of >/= 6 calves were greater in 2005 than 2000 (P x Hereford, Angus, Angus x Charolais, and Brahman (P Brahman Cross, Charolais, Charolais x Limousin, Hereford x Limousin, Limousin, Limousin x one-fourth Brahman, Longhorn, Saler and Simmental. Yellow-white face, black-white face, black, and gray feeder calves received an increase in selling price from 2000 to 2005 (P < 0.001). Although fewer horned feeder calves were sold in 2005 (P < 0.01), they received greater discounts in 2005 than 2000 (-$2.86 +/- 0.16 and -$0.51 +/- 0.09; P < 0.001). In 2005, large-framed feeder calves did not receive the premium detected in 2000, but medium-framed feeder calves in 2005 received a greater selling price compared with 2000. Feeder calves with a muscle score of 1 received a greater premium in 2005 compared with 2000 ($2.58 +/- 0.06 and $0.02 +/- 0.09, respectively; P < 0.001). Feeder calves with a muscle score of 2 were discounted in both years, but the discount in 2005 was not as great as in 2000 (P < 0.001). Full and tanked feeder calves received greater discounts in 2005 than in 2000 (P < 0.001). Discounts for fleshy and fat feeder calves were greater in 2005 than in 2000. Most factors

  18. Potential for Optical Sensor-Based Nitrogen Fertilization in Grain Sorghum (Sorghum bicolor L. Moench) in Arkansas

    Science.gov (United States)

    Rosales Rodriguez, Kamil

    Ground-based active-optical (GBAO) crop sensors have become an effective tool to improve nitrogen (N) use efficiency and to predict yield early in the growing season, particularly for grass crops. Commercially available canopy sensors calculate the normalized difference vegetative index (NDVI) by emitting light in the red and near infrared range of the electromagnetic spectrum. The NDVI is used to evaluate vigor status and to estimate yield potential. However, few studies have been conducted to compare the performance of commercially available sensors. Therefore, a study was conducted using the most common crop canopy sensors: i) N-Tech's GreenSeeker(TM) (GS), ii) Holland Scientific's Crop Circle(TM) (CC), and iii) Minolta's SPAD-502 chlorophyll content meter (CCM). The objective of this study was to find the optimum time for sensing and compare the relative performance of the sensors in estimating the yield potential of grain sorghum (Sorghum bicolor L. Moench). Treatments included six levels of N fertilization (0, 37, 74, 111, 148, and 185 kg N/ ha), applied in a single split 20 days after planting (DAP). Treatments were arranged in a randomized complete block design with five replications, in four locations in Arkansas, during 2012 and 2013. Sensors readings at vegetative growth stages V3, 4, 5 and 6. Results from simple regression analysis showed that the V3-V4 growth stage correlated better with grain yield than readings collected and any other time. In season estimated yield (INSEY) obtained at V3 captured 41, 57, 78, and 61% of the variation in grain sorghum yield when red NDVI of GS, red NDVI of CC, red edge for CC and CCM, respectively, were used. Results from these studies suggest that the CC sensor has a better potential for in-season site-specific N application in Arkansas than the GS sensor. The GS reflectance values appear to saturate after the V3 stage, in contrast with CC values that allow for discrimination past the V3 Stage. Therefore, the red

  19. Methods for estimating annual exceedance probability discharges for streams in Arkansas, based on data through water year 2013

    Science.gov (United States)

    Wagner, Daniel M.; Krieger, Joshua D.; Veilleux, Andrea G.

    2016-08-04

    In 2013, the U.S. Geological Survey initiated a study to update regional skew, annual exceedance probability discharges, and regional regression equations used to estimate annual exceedance probability discharges for ungaged locations on streams in the study area with the use of recent geospatial data, new analytical methods, and available annual peak-discharge data through the 2013 water year. An analysis of regional skew using Bayesian weighted least-squares/Bayesian generalized-least squares regression was performed for Arkansas, Louisiana, and parts of Missouri and Oklahoma. The newly developed constant regional skew of -0.17 was used in the computation of annual exceedance probability discharges for 281 streamgages used in the regional regression analysis. Based on analysis of covariance, four flood regions were identified for use in the generation of regional regression models. Thirty-nine basin characteristics were considered as potential explanatory variables, and ordinary least-squares regression techniques were used to determine the optimum combinations of basin characteristics for each of the four regions. Basin characteristics in candidate models were evaluated based on multicollinearity with other basin characteristics (variance inflation factor < 2.5) and statistical significance at the 95-percent confidence level (p ≤ 0.05). Generalized least-squares regression was used to develop the final regression models for each flood region. Average standard errors of prediction of the generalized least-squares models ranged from 32.76 to 59.53 percent, with the largest range in flood region D. Pseudo coefficients of determination of the generalized least-squares models ranged from 90.29 to 97.28 percent, with the largest range also in flood region D. The regional regression equations apply only to locations on streams in Arkansas where annual peak discharges are not substantially affected by regulation, diversion, channelization, backwater, or urbanization

  20. United States Domestic Research Reactor Infrastructure TRIGA Reactor Fuel Support

    International Nuclear Information System (INIS)

    The purpose of this technical paper is to provide status of the United State domestic Research Reactor Infrastructure (RRI) Program at the Idaho National Laboratory. This paper states the purpose of the program, lists the universities operating TRIGA reactors that are supported by the program, identifies anticipated fresh fuel needs for the reactor facilities, discusses spent fuel activities associated with the program, and addresses successes and planned activities for the program. (author)

  1. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-06-01

    During the 1960's and early 70's the author performed extensive design studies, analyses, and tests aimed at thermionic reactor concepts that differed significantly from those pursued by other investigators. Those studies, like most others under Atomic Energy Commission (AEC and DOE) and the National Aeronautics and Space Administration (NASA) sponsorship, were terminated in the early 1970's. Some of this work was previously published, but much of it was never made available in the open literature. U.S. interest in thermionic reactors resumed in the early 80's, and was greatly intensified by reports about Soviet ground and flight tests in the late 80's. This recent interest resulted in renewed U.S. thermionic reactor development programs, primarily under Department of Defense (DOD) and Department of Energy (DOE) sponsorship. Since most current investigators have not had an opportunity to study all of the author's previous work, a review of the highlights of that work may be of value to them. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling. Where the author's concepts differed from the later Topaz-2 design was in the relative location of the emitter and the collector. Placing the fueled emitter on the outside of the cylindrical diodes permits much higher axial conductances to reduce ohmic

  2. Applications of Research Reactors

    International Nuclear Information System (INIS)

    One of the IAEA's statutory objectives is to 'seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world.' One way this objective is achieved is through the publication of a range of technical series. Two of these are the IAEA Nuclear Energy Series and the IAEA Safety Standards Series. According to Article III.A.6 of the IAEA Statute, the safety standards establish 'standards of safety for protection of health and minimization of danger to life and property'. The safety standards include the Safety Fundamentals, Safety Requirements and Safety Guides. These standards are written primarily in a regulatory style, and are binding on the IAEA for its own programmes. The principal users are the regulatory bodies in Member States and other national authorities. The IAEA Nuclear Energy Series comprises reports designed to encourage and assist R and D on, and application of, nuclear energy for peaceful uses. This includes practical examples to be used by owners and operators of utilities in Member States, implementing organizations, academia, and government officials, among others. This information is presented in guides, reports on technology status and advances, and best practices for peaceful uses of nuclear energy based on inputs from international experts. The IAEA Nuclear Energy Series complements the IAEA Safety Standards Series. The purpose of the earlier publication, The Application of Research Reactors, IAEA-TECDOC-1234, was to present descriptions of the typical forms of research reactor use. The necessary criteria to enable an application to be performed were outlined for each one, and, in many cases, the minimum as well as the desirable requirements were given. This revision of the publication over a decade later maintains the original purpose and now specifically takes into account the changes in service requirements demanded by the relevant stakeholders. In particular, the significant improvements in

  3. Reactor technology: power conversion systems and reactor operation and maintenance

    International Nuclear Information System (INIS)

    The use of advanced fuels permits the use of coolants (organic, high pressure helium) that result in power conversion systems with good thermal efficiency and relatively low cost. Water coolant would significantly reduce thermal efficiency, while lithium and salt coolants, which have been proposed for DT reactors, will have comparable power conversion efficiencies, but will probably be significantly more expensive. Helium cooled blankets with direct gas turbine power conversion cycles can also be used with DT reactors, but activation problems will be more severe, and the portion of blanket power in the metallic structure will probably not be available for the direct cycle, because of temperature limitations. A very important potential advantage of advanced fuel reactors over DT fusion reactors is the possibility of easier blanket maintenance and reduced down time for replacement. If unexpected leaks occur, in most cases the leaking circuit can be shut off and a redundant cooling curcuit will take over the thermal load. With the D-He3 reactor, it appears practical to do this while the reactor is operating, as long as the leak is small enough not to shut down the reactor. Redundancy for Cat-D reactors has not been explored in detail, but appears feasible in principle. The idea of mobile units operating in the reactor chamber for service and maintenance of radioactive elements is explored

  4. Nuclear Reactor RA Safety Report, Vol. 4, Reactor

    International Nuclear Information System (INIS)

    RA research reactor is thermal heavy water moderated and cooled reactor. Metal uranium 2% enriched fuel elements were used at the beginning of its operation. Since 1976, 80% enriched uranium oxide dispersed in aluminium fuel elements were gradually introduced into the core and are the only ones presently used. Reactor core is cylindrical, having diameter 40 cm and 123 cm high. Reaktor core is made up of 82 fuel elements in aluminium channels, lattice is square, lattice pitch 13 cm. Reactor vessel is cylindrical made of 8 mm thick aluminium, inside diameter 140 cm and 5.5 m high surrounded with neutron reflector and biological shield. There is no containment, the reactor building is playing the shielding role. Three pumps enable circulation of heavy water in the primary cooling circuit. Degradation of heavy water is prevented by helium cover gas. Control rods with cadmium regulate the reactor operation. There are eleven absorption rods, seven are used for long term reactivity compensation, two for automatic power regulation and two for safety shutdown. Total anti reactivity of the rods amounts to 24%. RA reactor is equipped with a number of experimental channels, 45 vertical (9 in the core), 34 in the graphite reflector and two in the water biological shield; and six horizontal channels regularly distributed in the core. This volume include detailed description of systems and components of the RA reactor, reactor core parameters, thermal hydraulics of the core, fuel elements, fuel elements handling equipment, fuel management, and experimental devices

  5. The research reactor TRIGA Mainz

    International Nuclear Information System (INIS)

    Paper dwells upon the design and the operation of one of the German test reactors, namely, the TRIGA Mainz one (TRIGA: Training Research Isotope Production General Atomic). The TRIGA reactor is a pool test reactor the core of which contains a graphite reflector and is placed into 2 m diameter and 6.25 m height aluminum vessel. There are 75 fuel elements in the reactor core, and any of them contains about 36 g of 235U. The TRIGA reactors under the stable operation enjoy wide application to ensure tests and irradiation, namely: neutron activation analysis, radioisotope production, application of a neutron beam to ensure the physical, the chemical and the medical research efforts. Paper presents the reactor basic experimental program lines

  6. Spiral-shaped disinfection reactors

    KAUST Repository

    Ghaffour, Noreddine

    2015-08-20

    This disclosure includes disinfection reactors and processes for the disinfection of water. Some disinfection reactors include a body that defines an inlet, an outlet, and a spiral flow path between the inlet and the outlet, in which the body is configured to receive water and a disinfectant at the inlet such that the water is exposed to the disinfectant as the water flows through the spiral flow path. Also disclosed are processes for disinfecting water in such disinfection reactors.

  7. Industrializing the liquid metal reactor

    International Nuclear Information System (INIS)

    Commercial acceptance of the liquid metal reactor had its beginning with the Fermi reactor, over two decades ago. The pattern of industrialization since that time is discussed, contrasting domestic and foreign experience. The recent termination of the Clinch River reactor project marks a watershed in the U.S. approach towards commercialization. The increased emphasis on achieving cost competitive designs reflects an awareness that barriers to industrialization are institutional and financial, and not technological

  8. Acceptability of reactors in space

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.

    1981-04-01

    Reactors are the key to our future expansion into space. However, there has been some confusion in the public as to whether they are a safe and acceptable technology for use in space. The answer to these questions is explored. The US position is that when reactors are the preferred technical choice, that they can be used safely. In fact, it dies not appear that reactors add measurably to the risk associated with the Space Transportation System.

  9. Hydrogen Production in Fusion Reactors

    OpenAIRE

    Sudo, S.; Tomita, Y.; Yamaguchi, S.; Iiyoshi, A.; Momota, H.; Motojima, O.; Okamoto, M; Ohnishi, M.; Onozuka, M.; Uenosono, C.

    1993-01-01

    As one of methods of innovative energy production in fusion reactors without having a conventional turbine-type generator, an efficient use of radiation produced in a fusion reactor with utilizing semiconductor and supplying clean fuel in a form of hydrogen gas are studied. Taking the candidates of reactors such as a toroidal system and an open system for application of the new concepts, the expected efficiency and a concept of plant system are investigated.

  10. Fast reactor programme in India

    Indian Academy of Sciences (India)

    P Chellapandi; P R Vasudeva Rao; Prabhat Kumar

    2015-09-01

    Role of fast breeder reactor (FBR) in the Indian context has been discussed with appropriate justification. The FBR programme since 1985 till 2030 is highlighted focussing on the current status and future direction of fast breeder test reactor (FBTR), prototype fast breeder reactor (PFBR) and FBR-1 and 2. Design and technological challenges of PFBR and design and safety targets with means to achieve the same are the major highlights of this paper.

  11. Turning points in reactor design

    International Nuclear Information System (INIS)

    This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems

  12. Optimal control of nuclear reactors

    International Nuclear Information System (INIS)

    The modern control theory is applied to the design of control systems for experimental nuclear reactors that do not belong to power reactors, the component forms of optimal control systems for nuclear reactors are demonstrated. The adoption of output quadratic integral criterion and incomplete state feedback technique can make these systems both efficient and economical. Moreover, approximate handling methods are given so as to simplify the calculations in design. In addition, the adoptable reference values of parameters are given in the illustration

  13. Turning points in reactor design

    Energy Technology Data Exchange (ETDEWEB)

    Beckjord, E.S.

    1995-09-01

    This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems.

  14. Acceptability of reactors in space

    International Nuclear Information System (INIS)

    Reactors are the key to our future expansion into space. However, there has been some confusion in the public as to whether they are a safe and acceptable technology for use in space. The answer to these questions is explored. The US position is that when reactors are the preferred technical choice, that they can be used safely. In fact, it does not appear that reactors add measurably to the risk associated with the Space Transportation System

  15. Advanced Fission Reactor Program objectives

    International Nuclear Information System (INIS)

    The objective of an advanced fission reactor program should be to develop an economically attractive, safe, proliferation-resistant fission reactor. To achieve this objective, an aggressive and broad-based research and development program is needed. Preliminary work at Brookhaven National Laboratory shows that a reasonable goal for a research program would be a reactor combining as many as possible of the following features: (1) initial loading of uranium enriched to less than 15% uranium 235, (2) no handling of fuel for the full 30-year nominal core life, (3) inherent safety ensured by core physics, and (4) utilization of natural uranium at least 5 times as efficiently as light water reactors

  16. Reactor safety - an international task

    International Nuclear Information System (INIS)

    The dimensions and the significance of the task of ensuring reactor safety can be defined on the basis of experiences gained from Harrisburg and Chernobyl. The countries that use nuclear energy are tied together to a community by virtue of the risk they share. Therefore the GRS is working in close cooperation with the EC, OECD, IAEO and COMECON. This results in safety examinations of the Greifswald reactor, safety analyses of nuclear reactors in Germany, France and the USA and also considerations on the safety demands to be placed on new reactor concepts. (DG)

  17. Operating reactors licensing actions summary

    International Nuclear Information System (INIS)

    The operating reactors licensing actions summary is designed to provide the management of the Nuclear Regulatory Commission (NRC) with an overview of licensing actions dealing with operating power and nonpower reactors. These reports utilize data collected from the Division of Licensing in the Office of Nuclear Reactor Regulation and are prepared by the Office of Management and Program Analysis. This summary report is published primarily for internal NRC use in managing the operating reactors licensing actions program. Its content will change based on NRC management informational requirements

  18. Integrated modular water reactor: IMR

    International Nuclear Information System (INIS)

    The Mitsubishi Heavy Industries, Ltd. Has investigated on a concept on small scale reactor with economical efficiency comparable with large scale one. Aims of development on the integrated modular water reactor (IMR) of a small scale reactor plant concept consist in large construction cost reduction through adoption of technique specific to the small scale reactor and integrated production of plural units and in establishment of high safety target without reality in a large scale reactor to realize reduction of operation and maintenance costs by this reduction to simplification of operation and maintenance. Its concrete developmental targets are to make an integrated reactor with vessel size actually producible and the largest output, to remove feasibility of coolant loss accident (LOCA), to remove an accident with feasibility related to fuel fracture, to remove feasibility of nuclear reactor coolant to leak out from a storage vessel, to secure safety of plant without necessity of human and physical assistances from other plants at all on an accident, to make numbers of operators per unit output equal to those of large scale reactor, and to make working amounts at maintenance per unit output equal to large scale reactor by simplification of apparatus practice of rotation on main apparatus such as SG, and so on. Here were described on design concept and plan to realization. (G.K.)

  19. 3. Interindustry conference on reactor materials science

    International Nuclear Information System (INIS)

    This document contains abstracts on papers presented at the Third Interindustry Conference on Reactor Materials Science (Dimitrovgrad, 27-30 October 1992). The subject scope of the papers is a follows: fuel and fuel elements of power reactors; structural materials of fast breeder reactors and thermonuclear reactors; structural materials of WWER and RBMK type reactors; absorbers and moderators

  20. Helias reactor studies

    International Nuclear Information System (INIS)

    The Helias reactor is an upgraded version of the Wendelstein 7-X experiment. The magnetic field has 5 field periods and the main optimization principle is the reduction of the Pfirsch-Schlueter currents and the Shafranov shift, which has been verified by computations with the NEMEC and MFBE-codes. The modular coil system comprises 50 coils, which are constructed using NbTi-superconducting cables. The basic dimensions are: major radius 22 m, average plasma radius 1.8 m, magnetic field on axis 5 T, maximum field on the coils 10 T. Forces and stresses in the coil system have been investigated with the aid of the ANSYS code, which found maximum stress values of about 650 MPa in the coil casing. Helias configurations with 4 and 3 field periods have been constructed by starting from the 5-period case and by eliminating one or two periods while the shape of the coils is kept nearly invariant. In a first survey blanket concepts, developed for the DEMO tokamak, have been adapted to the Helias geometry, in particular, the solid breeder concept developed by FZK (Karlsruhe) has been extrapolated to the Helias geometry identifying the drawbacks and advantages of this concept. Furthermore, the liquid breeder concept using Li7-Pb83 and water-cooling is an interesting alternative for the Helias reactor. Maintenance of blanket and plasma facing components is possible through the portholes between modular coils. Numerical simulations of the start-up phase of the Helias reactor using the TOTAL-P code have confirmed the zero-dimensional modeling of the fusion plasma with the aid of empirical scaling laws. (author)

  1. EPSPS Gene Amplification in Glyphosate-Resistant Italian Ryegrass (Lolium perenne ssp. multiflorum) Populations from Arkansas (United States).

    Science.gov (United States)

    Salas, Reiofeli A; Scott, Robert C; Dayan, Franck E; Burgos, Nilda R

    2015-07-01

    Glyphosate-resistant Italian ryegrass was detected in Arkansas (United States) in 2007. In 2014, 45 populations were confirmed resistant in eight counties across the state. The level of resistance and resistance mechanisms in six populations were studied to assess the severity of the problem and identify alternative management approaches. Dose-response bioassays, glyphosate absorption and translocation experiments, herbicide target (EPSPS) gene sequence analysis, and gene amplification assays were conducted. The dose causing 50% growth reduction (GR50) was 7-19 times higher for the resistant population than for the susceptible standard. Uptake and translocation of (14)C-glyphosate were similar in resistant and susceptible plants, and no mutation in the EPSPS gene known to be associated with resistance to glyphosate was detected. Resistant plants contained from 11- to >100-fold more copies of the EPSPS gene than the susceptible plants, whereas the susceptible plants had only one copy of EPSPS. Plants surviving the recommended dose of glyphosate contained at least 10 copies. The EPSPS copy number was positively related to glyphosate resistance level (r = 80). Therefore, resistance to glyphosate in these populations is due to multiplication of the target site. Resistance mechanisms could be location-specific. Suppressing the mechanism for gene amplification may overcome resistance.

  2. Perceived Need for Substance Abuse Treatment among Illicit Stimulant Drug Users in Rural Areas of Ohio, Arkansas, and Kentucky

    Science.gov (United States)

    Falck, Russel S.; Wang, Jichuan; Carlson, Robert G.; Krishnan, Laura L.; Leukefeld, Carl; Booth, Brenda M.

    2007-01-01

    Non-medical drug use in rural communities in the United States is a significant and growing public health threat. Understanding what motivates drug users in rural areas to seek substance abuse treatment may help in addressing the problem. Perceived need for treatment, a construct indicative of problem recognition and belief in problem solution, has been identified as an important predictor of help-seeking behavior. This cross-sectional study used data collected through face-to-face interviews to examine factors associated with perceived need for drug abuse treatment among not-in-treatment, adult, illicit stimulant drug users (n=710) in rural areas of Ohio, Kentucky, and Arkansas. More than one-quarter of the sample perceived a need for treatment. Results from a stepwise multiple regression analysis showed that white users, users with better physical and mental health status, and occasional users of methamphetamine were significantly less likely to see a need for treatment. Users with higher Addiction Severity Index composite scores for family/social problems or legal problems, and users with prior drug abuse treatment experience were significantly more likely to perceive a need for treatment. These findings have practical implications for efforts addressing substance abuse in rural areas. PMID:17604917

  3. Disposal of chemical agents and munitions stored at Pine Bluff Arsenal, Pine Bluff, Arkansas. Final phase 1, Environmental report

    Energy Technology Data Exchange (ETDEWEB)

    Ensminger, J.T.; Hillsman, E.L.; Johnson, R.D.; Morrisey, J.A.; Staub, W.P.; Boston, C.R.; Hunsaker, D.B.; Leibsch, E.; Rickert, L.W.; Tolbert, V.R.; Zimmerman, G.P.

    1991-09-01

    The Pine Bluff Arsenal (PBA) near Pine Bluff, Arkansas, is one of eight continental United States (CONUS) Army installations where lethal unitary chemical agents and munitions are stored and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at PBA consists of approximately 12%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts). The purpose of this report is to examine the proposed implementation of on-site disposal at PBA in light of more recent and more detailed data than those on which the FPEIS is based. New population data were used to compute fatalities using the same computation methods and values for all other parameters as in the FPEIS. Results indicate that all alternatives are indistinguishable when the potential health impacts to the PBA community are considered. However, risks from on-site disposal are in all cases equal to or less than risks from other alternatives. Furthermore, no unique resources with the potential to prevent or delay implementation of on-site disposal at PBA have been identified.

  4. Hydrogeology and physical characteristics of water samples at the Red River aluminum site, Stamps, Arkansas, April 2001

    Science.gov (United States)

    Czarnecki, John B.; Stanton, Gregory P.; Freiwald, David A.

    2001-01-01

    The Red River Aluminum site near Stamps, Arkansas, contains waste piles of salt cake and metal byproducts from the smelting of aluminum. The waste piles are subjected to about 50 inches of rainfall a year, resulting in the dissolution of the salts and metal. To assess the potential threat to underlying ground-water resources at the site, its hydrogeology was characterized by measuring water levels and field parameters of water quality in 23 wells and at 2 surface-water sites. Seventeen of these monitor wells were constructed at various depths for this study to allow for the separate characterization of the shallow and deep ground-water systems, the calculation of vertical gradients, and the collection of water samples at different depths within the flow system. Lithologic descriptions from drill-hole cuttings and geophysical logs indicate the presence of interbedded sands, gravels, silts, and clays to depths of 65 feet. The regionally important Sparta aquifer underlies the site. Water levels in shallow wells indicate radial flow away from the salt-cake pile located near the center of the site. Flow in the deep system is to the west and southwest toward Bodcau Creek. Water-level data from eight piezometer nests indicate a downward hydraulic gradient from the shallow to deep systems across the site. Values of specific conductance (an indicator of dissolved salts) ranged from 215 to 196,200 microsiemens per centimeter and indicate that saline waters are being transported horizontally and vertically downward away from the site

  5. Arkansas Nuclear One IPE: An implementation of the EPRI generic framework for IPE back end (Level 2) analysis

    International Nuclear Information System (INIS)

    In Generic Letter 88-20, the NRC asked US nuclear power plant licensees to prepare individual plant probabilistic risk studies. These studies are commonly referred to as Individual Plant Examinations (IPEs). In response to the IPE Generic Letter, Energy Operations implemented an EPRI-developed generic framework for the Level 2 analysis portion of the Arkansas Nuclear One (ANO Units 1 and 2) IPEs. It begins with grouping the Level 1 core damage accident sequences having similar characteristics into a more manageable set of plant damage states (PDSs). This serves as the interface with the Level 1 PRA, and it provides the starting point for investigating the various severe accident progression scenarios and containment response. These investigations are aided by the use of the generic containment event trees (CETs). This paper presents the implementation of the generic framework for the ANO-2 IPE and describes the integrated Level 1/2 insights on the risk-dominant sequences, potential containment vulnerabilities, and identification of likely accident management strategies. The present understanding of some severe accident phenomena is still limited. Therefore, a parametric analysis of the ANO IPE Level 2 model, as intended in the generic framework, was conducted reflecting different viewpoints in the severe accident phenomena. In particular, this allowed NRC viewpoints on various phenomenological issues, as discussed in Appendix 1 of GL 88-20, to be evaluated in a straight forward manner

  6. Reactor coolant pump flywheel

    Science.gov (United States)

    Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

    2013-11-26

    A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

  7. Licensed operating reactors

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission's monthly Licensed Operating Reactors Status Summary Report provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management, from the Headquarters Staff of NRC's Office of Inspection and Enforcement, from NRC's Regional Offices, and from utilities. Since all of the data concerning operation of the units is provided by the utility operators less than two weeks after the end of the month, necessary corrections to published information are shown on the errata page

  8. FUEL ASSAY REACTOR

    Science.gov (United States)

    Spinrad, B.I.; Sandmeier, H.A.; Martens, F.H.

    1962-12-25

    A reactor having maximum sensitivity to perturbations is described comprising a core consisting of a horizontally disposed, rectangular, annular fuel zone containing enriched uranium dioxide dispersed in graphite, the concentration of uranium dioxide increasing from the outside to the inside of the fuel zone, an internal reflector of graphite containing an axial test opening disposed within the fuel zone, an external graphite reflector, means for changing the neutron spectrum in the test opening, and means for measuring perturbations in the neutron flux caused by the introduction of different fuel elements into the test opening. (AEC)

  9. Shutting down two reactors

    International Nuclear Information System (INIS)

    Nuclear power will be phased out of the swedish energy system during the first decades of the next century. Commissioned by the swedish government, the National Energy Administration reports a study on the possibilities for, and consequences of, an earlier shut down (1994-1996) of two of the twelve swedish power reactors. Some of the questions studied are: How much will the electricity price raise ?; How will the electricity consumption be affected ?; What are the alternatives to nuclear power ?; What will the cost be ? and What will the environmental effects be ?. (L.E.)

  10. Measurement in nuclear reactors

    International Nuclear Information System (INIS)

    A nuclear reactor construction has a flux detector comprising a bundle of fibre optics each having a bead incorporating a substance which scintillates on being struck by neutrons or gamma radiations. The other ends of the fibre optics terminate at an image intensifier. The optical fibres may be of glass made from a mixture of silica, alkaline earth metal oxide, cerous oxide and alkali metal oxide. The beads may be incorporated in a disc forming a detector head, which is in a protective guide tube, through which an inert gas may be passed. (author)

  11. TRIGA reactor operating experience

    International Nuclear Information System (INIS)

    The Oregon State TRIGA Reactor (OSTR) has been in operation 3 years. Last August it was upgraded from 250 kW to 1000 kW. This was accomplished with little difficulty. During the 3 years of operation no major problems have been experienced. Most of the problems have been minor in nature and easily corrected. They came from lazy susan (dry bearing), Westronics Recorder (dead spots in the range), The Reg Rod Magnet Lead-in Circuit (a new type lead-in wire that does not require the lead-in cord to coil during rod withdrawal hss been delivered, much better than the original) and other small corrections

  12. Reactor system safety assurance

    International Nuclear Information System (INIS)

    The philosophy of reactor safety is that design should follow established and conservative engineering practices, there should be safety margins in all modes of plant operation, special systems should be provided for accidents, and safety systems should have redundant components. This philosophy provides ''defense in depth.'' Additionally, the safety of nuclear power plants relies on ''safety systems'' to assure acceptable response to design basis events. Operating experience has shown the need to study plant response to more frequent upset conditions and to account for the influence of operators and non-safety systems on overall performance. Defense in depth is being supplemented by risk and reliability assessment

  13. The Oklo reactors

    International Nuclear Information System (INIS)

    The Oklo reactors comprise up to nine 235-U depleted zones in an uranium ore in the Republic of Gabon in West Africa. The depletion in fissile U-235 has been proved to have caused by nuclear chain reactions. The study of the Oklo phenomenon indicates that very efficient retardation mechanisms may operate in nature - at least under special conditions. A closer study of these processes ought to be made to establish the limitations to their occurrence. The Oklo sandstone formation today would probably be considered unacceptable as a host rock for a repository. (EG)

  14. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC (Nuclear Regulatory Commission) licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor.

  15. Licensed reactor nuclear safety criteria applicable to DOE reactors

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC [Nuclear Regulatory Commission] licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor

  16. Virtual nuclear reactor for education of nuclear reactor physics

    International Nuclear Information System (INIS)

    As one of projects that were programmed in the cultivation program for human resources in nuclear engineering sponsored by the Ministry of Economy, Trade and Industry, the development of a virtual reactor for education of nuclear reactor physics started in 2007. The purpose of the virtual nuclear reactor is to make nuclear reactor physics easily understood with aid of visualization. In the first year of this project, the neutron slowing down process was visualized. The data needed for visualization are provided by Monte Carlo calculations; The flights of the respective neutrons generated by nuclear fissions are traced through a reactor core until they disappear by neutron absorption or slow down to a thermal energy. With this visualization and an attached supplement textbook, it is expected that the learners can learn more clearly the physical implication of neutron slowing process that is mathematically described by the Boltzmann neutron transport equation. (author)

  17. Reactor Physics Analysis Models for a CANDU Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Bok

    2007-10-15

    Canada deuterium uranium (CANDU) reactor physics analysis is typically performed in three steps. At first, macroscopic cross-sections of the reference lattice is produced by modeling the reference fuel channel. Secondly macroscopic cross-sections of reactivity devices in the reactor are generated. The macroscopic cross-sections of a reactivity device are calculated as incremental cross-sections by subtracting macroscopic cross-sections of a three-dimensional lattice without reactivity device from those of a three-dimensional lattice with a reactivity device. Using the macroscopic cross-sections of the reference lattice and incremental cross-sections of the reactivity devices, reactor physics calculations are performed. This report summarizes input data of typical CANDU reactor physics codes, which can be utilized for the future CANDU reactor physics analysis.

  18. Reactor system on barge

    International Nuclear Information System (INIS)

    Floating electrical power plants or power plant barges add new dimensions to utility planners and agencies in the world. Intrinsically safe and economical reactors (ISER) employ steel reactor pressure vessels, which significantly reduce the weight as compared with PIUS, and provide siting versatility including barge-mounted plants. In this paper, the outline of power plant barges and barge-mounted ISERs is described. Besides their mobility, power plant barges have the salient advantages such as short delivery time and better quality control due to the outfitting in shipyards. These power plant barges may be temporarily moored or permanently grounded in shallow water at the centers of industrial complexes or the suitable areas adjacent to them, and satisfy the increasing needs for electric power. A cost-effective and technically perfect barge positioning system should be designed to meet the specific requirement for the location and its condition. Offshore siting away from coast may be applicable only to large plants of 1,000 MWe or more, and inshore siting and coastal or river siting are considered for an ISER-200 barge-mounted plant. The system of a barge-mounted ISER plant is discussed in the case of a floating type and the type on a seismic base isolator. (Kako, I.)

  19. Tokamak experimental power reactor

    International Nuclear Information System (INIS)

    A tokamak experimental power reactor has been designed that is capable of producing net electric power over a wide range of possible operating conditions. A net production of 81 MW of electricity is expected from the design reference conditions that assume a value of 0.07 for beta-toroidal, a maximum toroidal magnetic field of 9 T and a thermal conversion efficiency of 30%. Impurity control is achieved through the use of a low-Z first wall coating. This approach allows a burn time of 60 seconds without the incorporation of a divertor. The system is cooled by a dual pressurized water/steam system that could potentially provide thermal efficiencies as high as 39%. The first surface facing the plasma is a low-Z coated water cooled panel that is attached to a 20 cm thick blanket module. The vacuum boundary is removed a total of 22 cm from the plasma, thereby minimizing the amount of radiation damage in this vital component. Consideration is given in the design to the possible use of the EPR as a materials test reactor. It is estimated that the total system could be built for less than 550 million dollars

  20. The EPR reactor NDE

    International Nuclear Information System (INIS)

    In May 2006, Electricite de France decided to launch the building of the first EPRR Reactor on the Flamanville site in Normandy. The 'Flamanville 3' EPR unit is the first one to be subjected to the French Ministerial Orders of the 10 November 1999 and of the 13 December 2005 from the design phase. According to these orders, the non destructive examination (NDE) planned for the in service inspection (ISI) and for the pre service inspection (PSI) must be operational with a compulsory formal qualification. The PSI is a complete inspection of the main primary and secondary systems. The PSI's objective is to perform before the first core loading all the NDE planned for the future ISI in the same conditions, in order to have a reliable reference for the detection or for the evaluation of the possible damages during the ISI. The 'Flamanville 3' PSI is planned to start end 2010. The program consists of the development and the qualification of the NDE compatible with this new generation reactor's challenges. The paper is about: - the main EPR's objectives and the technological evolutions, - the main component modifications (which have an impact on the NDE), - the place of ISI in the general safety demonstration, - the main inspection objectives, - the NDE qualification process, - the approach to set up the ISI program, - the ISI program. (authors)

  1. Status of Japanese university reactors

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Yoshiaki [Research Reactor Institute, Kyoto Univ., Kumatori, Osaka (Japan)

    1999-08-01

    Status of Japanese university reactors, their role and value in research and education, and the spent fuel problem are presented. Some of the reactors are now faced by severe difficulties in continuing their operation services. The point of measures to solve the difficulties is suggested. (author)

  2. Brookhaven leak reactor to close

    CERN Multimedia

    MacIlwain, C

    1999-01-01

    The DOE has announced that the High Flux Beam Reactor at Brookhaven is to close for good. Though the news was not unexpected researchers were angry the decision had been taken before the review to assess the impact of reopening the reactor had been concluded (1 page).

  3. Reactor Neutrino Physics -- An Update

    OpenAIRE

    Boehm, Felix

    1999-01-01

    We review the status and the results of reactor neutrino experiments. Long baseline oscillation experiments at Palo Verde and Chooz have provided limits for the oscillation parameters while the recently proposed Kamland experiment at a baseline of more than 100km is now in the planning stage. We also describe the status of neutrino magnetic moment experiments at reactors.

  4. Chemical-vapor-deposition reactor

    Science.gov (United States)

    Chern, S.

    1979-01-01

    Reactor utilizes multiple stacked trays compactly arranged in paths of horizontally channeled reactant gas streams. Design allows faster and more efficient deposits of film on substrates, and reduces gas and energy consumption. Lack of dead spots that trap reactive gases reduces reactor purge time.

  5. Status of Water Levels and Selected Water-Quality Conditions in the Mississippi River Valley Alluvial Aquifer in Eastern Arkansas, 2004

    Science.gov (United States)

    Schrader, T.P.

    2006-01-01

    During the spring of 2004, water levels were measured in 684 wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas. Ground-water levels are affected by intense ground-water withdrawals resulting in extensive potentiometric depressions. In 2004, the highest water-level altitude measured was 293 feet above National Geodetic Vertical Datum of 1929 in northeastern Clay County. The lowest water-level altitude measured was 76 feet above National Geodetic Vertical Datum of 1929 in the center of Arkansas County. A large depression in the potentiometric surface was located in Arkansas, Lonoke, and Prairie Counties during 1998 and persisted to 2002. The area enclosed in the 100-foot contour in Arkansas County in 2004 is about the same as in 2002, however, the area enclosed in the 100-foot contour in Lonoke and Prairie Counties in 2004 has receded. Two shallower cones of depressions were located in Craighead, Cross, and Poinsett Counties and St. Francis, Woodruff, Lee, and Monroe Counties west of Crowleys Ridge during 1998. The 2004 potentiometricsurface map shows that the areas enclosed by the 140-foot contour have continued to expand. A map of changes in water-level measurements between 2000 and 2004 was constructed using the difference between water-level measurements from 625 wells reported in this report and the 2000 Mississippi River Valley alluvial aquifer report. Water-level changes between 2000 and 2004 ranged from -31.1 feet to 16.3 feet, with a mean of -0.7 feet (negative changes indicating water-level declines, positive changes indicating water-level rises). The largest rise of 16.3 feet is in Arkansas County and the largest decline of -31.1 feet is in Prairie County. Long-term water-level changes were calculated for 134 wells in the alluvial aquifer for the period from 1980 to 2004. The mean annual decline in water level for the entire study area was -0.31 feet per year with a range of -1.35 feet per year to 0.84 feet per year. The

  6. Cooling system for reactor container

    International Nuclear Information System (INIS)

    Purpose: To effectively cool a reactor container upon reactor shutdown with no intrusion of metal corrosion products in coolants into the main steam pipe in a BWR type reactor. Constitution: A clean up system comprising a pipeway, a recycling pump, a non-regenerative heat exchanger and a primary coolant purifier and a regenerative heat exchanger is provided branched from a residual heat removing system and the clean up system is connected by way of a valve to a feedwater pipeway, as well as connected by way of the pipeway to the main steam pipeway at the midway of two main steam separation valves outside of the reactor container. This enables to prevent metal corrosion products floating on the surface of reactor water from introducing into the main steam pipe when the pressure vessel is filled with water. Then, since the pressure vessel is filled with primary coolants, the pressure vessel can be cooled uniformly in a short time. (Ikeda, J.)

  7. Engineering reactors for catalytic reactions

    Indian Academy of Sciences (India)

    Vivek V Ranade

    2014-03-01

    Catalytic reactions are ubiquitous in chemical and allied industries. A homogeneous or heterogeneous catalyst which provides an alternative route of reaction with lower activation energy and better control on selectivity can make substantial impact on process viability and economics. Extensive studies have been conducted to establish sound basis for design and engineering of reactors for practising such catalytic reactions and for realizing improvements in reactor performance. In this article, application of recent (and not so recent) developments in engineering reactors for catalytic reactions is discussed. Some examples where performance enhancement was realized by catalyst design, appropriate choice of reactor, better injection and dispersion strategies and recent advances in process intensification/ multifunctional reactors are discussed to illustrate the approach.

  8. Directions in advanced reactor technology

    International Nuclear Information System (INIS)

    Successful nuclear power plant concepts must simultaneously performance in terms of both safety and economics. To be attractive to both electric utility companies and the public, such plants must produce economical electric energy consistent with a level of safety which is acceptable to both the public and the plant owner. Programs for reactor development worldwide can be classified according to whether the reactor concept pursues improved safety or improved economic performance as the primary objective. When improved safety is the primary goal, safety enters the solution of the design problem as a constraint which restricts the set of allowed solutions. Conversely, when improved economic performance is the primary goal, it is allowed to be pursued only to an extent which is compatible with stringent safety requirements. The three major reactor coolants under consideration for future advanced reactor use are water, helium and sodium. Reactor development programs focuses upon safety and upon economics using each coolant are being pursued worldwide. These programs are discussed

  9. Simulator for materials testing reactors

    International Nuclear Information System (INIS)

    A real-time simulator for both reactor and irradiation facilities of a materials testing reactor, “Simulator of Materials Testing Reactors”, was developed for understanding reactor behavior and operational training in order to utilize it for nuclear human resource development and to promote partnership with developing countries which have a plan to introduce nuclear power plant. The simulator is designed based on the JMTR (Japan Materials Testing Reactor), and it simulates operation, irradiation tests and various kinds of anticipated operational transients and accident conditions caused by the reactor and irradiation facilities. The development of the simulator was sponsored by the Japanese government as one of the specialized projects of advanced research infrastructure in order to promote basic as well as applied researches. This report summarizes the simulation components, hardware specification and operation procedure of the simulator. (author)

  10. Antineutrino Monitoring of Thorium Reactors

    CERN Document Server

    Akindele, Oluwatomi A; Norman, Eric B

    2015-01-01

    Various groups have demonstrated that antineutrino monitoring can be successful in assessing the plutonium content in water-cooled nuclear reactors for nonproliferation applications. New reactor designs and concepts incorporate nontraditional fuels types and chemistry. Understanding how these properties affect the antineutrino emission from a reactor can extend the applicability of antineutrino monitoring.Thorium molten salt reactors (MSR) breed U-233, that if diverted constitute an IAEA direct use material. The antineutrino spectrum from the fission of U-233 has been determined, the feasibility of detecting the diversion of a significant quantity, 8 kg of U-233, within the IAEA timeliness goal of 30 days has been evaluated. The antineutrino emission from a thorium reactor operating under normal conditions is compared to a diversion scenario at a 25 meter standoff by evaluating the daily antineutrino count rate and the energy spectrum of the detected antineutrinos. It was found that the diversion of a signifi...

  11. Fast reactors and nuclear nonproliferation

    International Nuclear Information System (INIS)

    Problems are discussed with regard to nuclear fuel cycle resistance in fast reactors to nuclear proliferation risk due to the potential for use in military programs of the knowledge, technologies and materials gained from peaceful nuclear power applications. Advantages are addressed for fast reactors in the creation of a more reliable mode of nonproliferation in the closed nuclear fuel cycle in comparison with the existing fully open and partially closed fuel cycles of thermal reactors. Advantages and shortcomings are also discussed from the point of view of nonproliferation from the start with fast reactors using plutonium of thermal reactor spent fuel and enriched uranium fuel to the gradual transition using their own plutonium as fuel. (author)

  12. Automated reactor records evaluation framework

    International Nuclear Information System (INIS)

    The only truly reliable method for core physics code validation is comparison against experimental data – and for power nuclear reactors, the only reasonably acquirable kind of experimental data are the reactor records. However, the amount of the data coming from the reactor operation is often so vast that it can be discouraging for the code developers to use it properly. Thus, the validation package is further reduced because the data is hard to use. This paper presents an elaborate, fully automated framework, which was designed and implemented in our institute, for reactor records processing and its use for core physics code validation. The workflow, implemented as a Web 2.0 application, provides a practical and painless solution for use of reactor records data for code development and validation. (author)

  13. Strategic planning for research reactors. Guidance for reactor managers

    International Nuclear Information System (INIS)

    The purpose of this publication is to provide guidance on how to develop a strategic plan for a research reactor. The IAEA is convinced of the need for research reactors to have strategic plans and is issuing a series of publications to help owners and operators in this regard. One of these covers the applications of research reactors. That report brings together all of the current uses of research reactors and enables a reactor owner or operator to evaluate which applications might be possible with a particular facility. An analysis of research reactor capabilities is an early phase in the strategic planning process. The current document provides the rationale for a strategic plan, outlines the methodology of developing such a plan and then gives a model that may be followed. While there are many purposes for research reactor strategic plans, this report emphasizes the use of strategic planning in order to increase utilization. A number of examples are given in order to clearly illustrate this function

  14. Neutrino Experiments at Reactors

    Science.gov (United States)

    Reines, F.; Gurr, H. S.; Jenkins, T. L.; Munsee, J. H.

    1968-09-09

    A description is given of the electron-antineutrino program using a large fission reactor. A search has been made for a neutral weak interaction via the reaction (electron antineutrino + d .> p + n + electron antineutrino), the reaction (electron antineutrino + d .> n + n + e{sup +}) has now been detected, and an effort is underway to observe the elastic scattering reaction (electron antineutrino + e{sup -} .> electron antineutrino + e{sup -}) as well as to measure more precisely the reaction (electron antineutrino + p .> n + e{sup+}). The upper limit on the elastic scattering reaction which we have obtained with our large composite NaI, plastic, liquid scintillation detector is now about 50 times the predicted value.

  15. Licensed operating reactors

    International Nuclear Information System (INIS)

    The Nuclear Regulatory Commission's annual summary of licensed nuclear power reactor data is based primarily on the report of operating data submitted by licensees for each unit for the month of December because that report contains data for the month of December, the year to date (in this case calendar 1990) and cumulative data, usually from the date of commercial operation. The data is not independently verified, but various computer checks are made. The report is divided into two sections. The first contains summary highlights and the second contains data on each individual unit in commercial operation. Section 1 capacity and availability factors are simple arithmetic averages. Section 2 items in the cumulative column are generally as reported by the licensee and notes as to the use of weighted averages and starting dates other than commercial operation are provided

  16. Reactor safety systems

    International Nuclear Information System (INIS)

    The spectrum of possible accidents may become characterized by the 'maximum credible accident', which will/will not happen. Similary, the performance of safety systems in a multitude of situations is sometimes simplified to 'the emergency system will/will not work' or even 'reactors are/ are not safe'. In assessing safety, one must avoid this fallacy of reducing a complicated situation to the simple black-and-white picture of yes/no. Similarly, there is a natural tendency continually to improve the safety of a system to assure that it is 'safe enough'. Any system can be made safer and there is usually some additional cost. It is important to balance the increased safety against the increased costs. (orig.)

  17. Reactor control rod

    International Nuclear Information System (INIS)

    Object: To enable quick descent of a control rod body even when some relative phase deviation between upper drive means and wrapper tube is produced, while permitting a coolant to effectively flow into a protective tube irrespective of the position of the control rod body. Structure: In a control rod used for a nuclear reactor such as a fast breeder, an orifice which dispenses with a cylindrical guide tube and has a greater inner diameter than the outer diameter of the protective tube of the control rod body is provided on the inner side of a wrapper tube, thus permitting smooth operation of the control rod body and also permitting the coolant to effectively flow into the protective tube irrespective of the control rod body. (Horiuchi, T.)

  18. Nuclear reactor spacer assembly

    International Nuclear Information System (INIS)

    A fuel assembly for a nuclear reactor is disclosed wherein the fuel element receiving and supporting grid is comprised of a first metal, the guide tubes which pass through the grid assembly are comprised of a second metal and the grid is supported on the guide tubes by means of expanded sleeves located intermediate the grid and guide tubes. The fuel assembly is fabricated by inserting the sleeves, of initial outer diameter commensurate with the guide tube outer diameters, through the holes in the grid assembly provided for the guide tubes and thereafter expanding the sleeves radially outwardly along their entire length such that the guide tubes can subsequently be passed through the sleeves. The step of radial expansion, as a result of windows provided in the sleeves having dimensions commensurate with the geometry of the grid, mechanically captures the grid and simultaneously preloads the sleeve against the grid whereby relative motion between the grid and guide tube will be precluded

  19. Nuclear reactor measurement system

    International Nuclear Information System (INIS)

    An instrument to detect the temperature and flow-rate of the liquid metal current of a coolant fluid sample from adjacent sub-assemblies of a liquid metal-cooled nuclear reactor is described. It includes three thermocouple hot junctions mounted in series, each intended for exposure to a sample-current from a single sub-assembly, electromagnetic coils being mounted around an induction core which detects variations in the liquid metal flow-rate by deformation of the lines of flux. The instrument may also include a thermocouple to detect the mean temperature of the sample-current of coolant fluid from several sources, the result being that the temperature of the coolant fluid current in a sub-assembly may be inferred from the three temperature readings associated with this sub-assembly

  20. OECD: Halden reactor project

    International Nuclear Information System (INIS)

    The work at the Project has continued in the two main fields: test fuel irradiation and fuel research, and computer based process supervision and control. Organizations participating in the Project continue to have their fuel irradiated in the Halden Reactor in instrumented test assemblies designed and manufactured by the Project. The Project's fuel studies continue to focus on specific subjects such as fuel pellet/cladding interaction and heat transfer, fission product release and fuel behavior under loss of coolant conditions. The work on process control and supervision continues in the highly relevant fields of core control and operator-process communication. A system for predictive core control is being developed while special mathematical methods for core power distribution control are being studied. Operator-process communication studies comprise use of computer simulation on colour display as important ingredients, while the work on developing a system for interactive plant disturbance analysis continues

  1. Tokamak fusion reactor exhaust

    International Nuclear Information System (INIS)

    This report presents a compilation of papers dealing with reactor exhaust which were produced as part of the TIGER Tokamak Installation for Generating Electricity study at Culham. The papers are entitled: (1) Exhaust impurity control and refuelling. (2) Consideration of the physical problems of a self-consistent exhaust and divertor system for a long burn Tokamak. (3) Possible bundle divertors for INTOR and TIGER. (4) Consideration of various magnetic divertor configurations for INTOR and TIGER. (5) A appraisal of divertor experiments. (6) Hybrid divertors on INTOR. (7) Refuelling and the scrape-off layer of INTOR. (8) Simple modelling of the scrape-off layer. (9) Power flow in the scrape-off layer. (10) A model of particle transport within the scrape-off plasma and divertor. (11) Controlled recirculation of exhaust gas from the divertor into the scrape-off plasma. (U.K.)

  2. Safety review, assessment and inspection on research reactors, experimental reactors, nuclear heating reactors and critical facilities

    International Nuclear Information System (INIS)

    The NNSA organized mainly in 1999 to complete the verification loop in core of the high flux experimental reactor with the 2000 kW fuel elements, the re-starting of China Pulsed Reactor, review and assessment on nuclear safety for the restarting of the Uranium-water critical Facility and treat the fracture event with the fuel tubes in the HWRR

  3. Effects of aquifer storage and recovery activities on water quality in the Little Arkansas River and Equus Beds Aquifer, south-central Kansas, 2011-14

    Science.gov (United States)

    Stone, Mandy L.; Garrett, Jessica D.; Poulton, Barry C.; Ziegler, Andrew C.

    2016-07-18

    The Equus Beds aquifer in south-central Kansas is aprimary water source for the city of Wichita. The Equus Beds aquifer storage and recovery (ASR) project was developed to help the city of Wichita meet increasing current (2016) and future water demands. The Equus Beds ASR project pumps water out of the Little Arkansas River during above-base flow conditions, treats it using drinking-water quality standards as a guideline, and recharges it into the Equus Beds aquifer for later use. Phase II of the Equus Beds ASR project currently (2016) includes a river intake facility and a surface-water treatment facility with a 30 million gallon per day capacity. Water diverted from the Little Arkansas River is delivered to an adjacent presedimentation basin for solids removal. Subsequently, waste from the surface-water treatment facility and the presedimentation basin is returned to the Little Arkansas River through a residuals return line. The U.S. Geological Survey, in cooperation with the city of Wichita, developed and implemented a hydrobiological monitoring program as part of the ASR project to characterize and quantify the effects of aquifer storage and recovery activities on the Little Arkansas River and Equus Beds aquifer water quality.Data were collected from 2 surface-water sites (one upstream and one downstream from the residuals return line), 1 residuals return line site, and 2 groundwater well sites (each having a shallow and deep part): the Little Arkansas River upstream from the ASR facility near Sedgwick, Kansas (upstream surface-water site 375350097262800), about 0.03 mile (mi) upstream from the residuals return line site; the Little Arkansas River near Sedgwick, Kans. (downstream surface-water site 07144100), about 1.68 mi downstream from the residuals return line site; discharge from the Little Arkansas River ASR facility near Sedgwick, Kansas (residuals return line site 375348097262800); 25S 01 W 07BCCC01 SMW–S11 near CW36 (MW–7 shallow groundwater well

  4. Power Reactors. Appendix VIII

    International Nuclear Information System (INIS)

    Decommissioning of nuclear facilities in many countries has evolved into a mature industry that has benefited from experience gained from previous projects and decommissioning costs can now be estimated to a good degree of accuracy. As a result of lessons learned, future decommissioning projects can be performed with higher levels of efficiency. Decommissioning of old power reactors is in progress in several countries. In some cases, decommissioning has been completed (i.e. plant sites have been released from regulatory control), while in other countries decommissioning is still in progress. Several large power reactors have been successfully decommissioned since 1995. The key areas of particular importance for decommissioning are decontamination, radiation protection, dismantling and demolition. The technologies which can be used for these tasks are commonly available on the market, but effective decommissioning still depends on an optimal choice of technologies, including site specific developments. It is not possible to recommend the use of a single specific technology for dismantling, demolition, segmentation or decontamination; rather, it is good practice to take into account as much information as possible from other decommissioning projects and to draw comparisons between various techniques in order to choose the one with the best performance in a particular situation. The exchange of information on all types of decommissioning experience, including decommissioning techniques and their applicability as well as disadvantages for specific tasks, is taking place on various levels, such as: — Collaborative working groups established by international organizations such as the IAEA, the OECD Nuclear Energy Agency and the European Commission and the publication of technical reports by such organizations; — National and international conferences; — Bilateral or multilateral cooperation and information exchange between organizations with responsibilities for

  5. Advanced fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, Yukihiro [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2003-04-01

    The main subjects on fusion research are now on D-T fueled fusion, mainly due to its high fusion reaction rate. However, many issues are still remained on the wall loading by the 14 MeV neutrons. In the case of D-D fueled fusion, the neutron wall loading is still remained, though the technology related to tritium breeding is not needed. The p-{sup 6}Li and p-{sup 11}B fueled fusions are not estimated to be the next generation candidate until the innovated plasma confinement technologies come in useful to achieve the high performance plasma parameters. The fusion reactor of D-{sup 3}He fuels has merits on the smaller neutron wall loading and tritium handling. However, there are difficulties on achieving the high temperature plasma more than 100 keV. Furthermore the high beta plasma is needed to decrease synchrotron radiation loss. In addition, the efficiency of the direct energy conversion from protons coming out from fusion reaction is one of the key parameters in keeping overall power balance. Therefore, open magnetic filed lines should surround the plasma column. In this paper, we outlined the design of the commercial base reactor (ARTEMIS) of 1 GW electric output power configured by D-{sup 3}He fueled FRC (Field Reversed Configuration). The ARTEMIS needs 64 kg of {sup 3}He per a year. On the other hand, 1 million tons of {sup 3}He is estimated to be in the moon. The {sup 3}He of about 10{sup 23} kg are to exist in gaseous planets such as Jupiter and Saturn. (Y. Tanaka)

  6. Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Following the accident at Chernobyl nuclear reactor, WHO organized on 6 May 1986 in Copenhagen a one day consultation of experts with knowledge in the fields of meteorology, radiation protection, biological effects, reactor technology, emergency procedures, public health and psychology in order to analyse the development of events and their consequences and to provide guidance as to the needs for immediate public health action. The present report provides detailed information on the transportation and dispersion of the radioactive material in the atmosphere, especially volatile elements, during the release period 26 April - 5 May. Presented are the calculated directions and locations of the radioactive plume over Europe in the first 5 days after the accident, submitted by the Swedish Meteorological and Hydrological Institute. The calculations have been made for two heights, 1500m and 750m and the plume directions are grouped into five periods, covering five European areas. The consequences of the accident inside the USSR and the radiological consequences outside the USSR are presented including the exposure routes and the biological effects, paying particular attention to iodine-131 effects. Summarized are the first reported measured exposure rates above background, iodine-131 deposition and concentrations in milk and the remedial actions taken in various European countries. Concerning the cesium-137 problem, based on the UNSCEAR assessment of the consequences of the nuclear fallout, one concludes that the cesium contamination outside the USSR is not likely to cause any serious problems. Finally, the conclusions and the recommendations of the meeting, taking into account both the short-term and longer term considerations are presented

  7. Nuclear reactor fuelling machine

    International Nuclear Information System (INIS)

    The refuelling machine described comprises a rotatable support structure having a guide tube attached to it by a parellel linkage mechanism, whereby the guide tube can be displaced sideways from the support structure. A gripper unit is housed within the guide tube for gripping the end of a fuel assembly or other reactor component and has means for maintenance in the engaging condition during travel of the unit along the guide tube, except for a small portion of the travel at one end of the guide tube, where the inner surface of the guide tube is shaped so as to maintain the gripper unit in a disengaging condition. The gripper unit has a rotatable head, means for moving it linearly within the guide tube so that a component carried by the unit can be housed in the guide tube, and means for rotating the head of the unit through 1800 relative to its body, to effect rotation of a component carried by the unit. The means for rotating the head of the gripper unit comprises ring and pinion gearing, operable through a series of rotatable shafts interconnected by universal couplings. The reason for provision for 1800 rotation is that due to the variation in the neutron flux across the reactor core the side of a fuel assembly towards the outside of the core will be subjected to a lower neutron flux and therefore will grow less than the side of the fuel assembly towards the inside of the core. This can lead to bowing and possible jamming of the fuel assemblies. Full constructional details are given. See also BP 1112384. (U.K.)

  8. Reliability of reactor materials

    International Nuclear Information System (INIS)

    This report is the final technical report of the fracture mechanics part of the Reliability of Reactor Materials Programme, which was carried out at the Technical Research Centre of Finland (VTT) through the years 1981 to 1983. Research and development work was carried out in five major areas, viz. statistical treatment and modelling of cleavage fracture, crack arrest, ductile fracture, instrumented impact testing as well as comparison of numerical and experimental elastic-plastic fracture mechanics. In the area of cleavage fracture the critical variables affecting the fracture of steels are considered in the frames of a statistical model, so called WST-model. Comparison of fracture toughness values predicted by the model and corresponding experimental values shows excellent agreement for a variety of microstructures. different posibilities for using the model are discussed. The development work in the area of crack arrest testing was concentrated in the crack starter properties, test arrangement and computer control. A computerized elastic-plastic fracture testing method with a variety of test specimen geometries in a large temperature range was developed for a routine stage. Ductile fracture characteristics of reactor pressure vessel steel A533B and comparable weld material are given. The features of a new, patented instrumented impact tester are described. Experimental and theoretical comparisons between the new and conventional testers indicated clearly the improvements achieved with the new tester. A comparison of numerical and experimental elastic-plastic fracture mechanics capabilities at VTT was carried out. The comparison consisted of two-dimensional linear elastic as well as elastic-plastic finite element analysis of four specimen geometries and equivalent experimental tests. (author)

  9. Licensed reactor nuclear safety criteria applicable to DOE reactors

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards.

  10. Licensed reactor nuclear safety criteria applicable to DOE reactors

    International Nuclear Information System (INIS)

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards

  11. Regional potentiometric surface of the Ozark aquifer in Arkansas, Kansas, Missouri, and Oklahoma, November 2014–January 2015

    Science.gov (United States)

    Nottmeier, Anna M.

    2015-12-21

    The Ozark aquifer, within the Ozark Plateaus aquifer system (herein referred to as the “Ozark system”), is the primary groundwater source in the Ozark Plateaus physiographic province (herein referred to as the “Ozark Plateaus”) of Arkansas, Kansas, Missouri, and Oklahoma. Groundwater from the Ozark system has historically been an important part of the water resource base, and groundwater availability is a concern in some areas; dependency on the Ozark aquifer as a water supply has caused evolving, localized issues. The construction of a regional potentiometric-surface map of the Ozark aquifer is needed to aid assessment of current and future groundwater use and availability. The regional potentiometric-surface mapping is part of the U.S. Geological Survey (USGS) Groundwater Resources Program initiative (http://water.usgs.gov/ogw/gwrp/activities/regional.html) and the Ozark system groundwater availability project (http://ar.water.usgs.gov/ozarks), which seeks to quantify current groundwater resources, evaluate changes in these resources over time, and provide the information needed to simulate system response to future human-related and environmental stresses.The Ozark groundwater availability project objectives include assessing (1) growing demands for groundwater and associated declines in groundwater levels as agricultural, industrial, and public supply pumping increases to address needs; (2) regional climate variability and pumping effects on groundwater and surface-water flow paths; (3) effects of a gradual shift to a greater surface-water dependence in some areas; and (4) shale-gas production requiring groundwater and surface water for hydraulic fracturing. Data compiled and used to construct the regional Ozark aquifer potentiometric surface will aid in the assessment of those objectives.

  12. United States Domestic Research Reactor Infrastructure TRIGA Reactor Fuel Support

    International Nuclear Information System (INIS)

    The United State Domestic Research Reactor Infrastructure Program at the Idaho National Laboratory manages and provides project management, technical, quality engineering, quality inspection and nuclear material support for the United States Department of Energy sponsored University Reactor Fuels Program. This program provides fresh, unirradiated nuclear fuel to Domestic University Research Reactor Facilities and is responsible for the return of the DOE-owned, irradiated nuclear fuel over the life of the program. This presentation will introduce the program management team, the universities supported by the program, the status of the program and focus on the return process of irradiated nuclear fuel for long term storage at DOE managed receipt facilities. It will include lessons learned from research reactor facilities that have successfully shipped spent fuel elements to DOE receipt facilities.

  13. On reactor type comparisons for the next generation of reactors

    International Nuclear Information System (INIS)

    In this paper, we present a broad comparison of studies for a selected set of parameters for different nuclear reactor types including the next generation. This serves as an overview of key parameters which provide a semi-quantitative decision basis for selecting nuclear strategies. Out of a number of advanced reactor designs of the LWR type, gas cooled type, and FBR type, currently on the drawing board, the Advanced Light Water Reactors (ALWR) seem to have some edge over other types of the next generation of reactors for the near-term application. This is based on a number of attributes related to the benefit of the vast operating experience with LWRs coupled with an estimated low risk profile, economics of scale, degree of utilization of passive systems, simplification in the plant design and layout, modular fabrication and manufacturing. 32 refs., 1 fig., 3 tabs

  14. Ageing management for research reactors

    International Nuclear Information System (INIS)

    During the past several years, ageing of research reactor facilities continues to be an important safety issue. Despite the efforts exerted by operating organizations and regulatory authorities worldwide to address this issue, the need for an improved strategy as well as the need for establishing and implementing a systematic approach to ageing management at research reactors was identified. This paper discusses, on the basis of the IAEA Safety Standards, the effect of ageing on the safety of research reactors and presents a proactive strategy for ageing management. A systematic approach for ageing management is developed and presented together with its key elements, along with practical examples for their application. (author)

  15. Fueling of tandem mirror reactors

    International Nuclear Information System (INIS)

    This paper summarizes the fueling requirements for experimental and demonstration tandem mirror reactors (TMRs), reviews the status of conventional pellet injectors, and identifies some candidate accelerators that may be needed for fueling tandem mirror reactors. Characteristics and limitations of three types of accelerators are described; neutral beam injectors, electromagnetic rail guns, and laser beam drivers. Based on these characteristics and limitations, a computer module was developed for the Tandem Mirror Reactor Systems Code (TMRSC) to select the pellet injector/accelerator combination which most nearly satisfies the fueling requirements for a given machine design

  16. Concept for LEU Burst Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Steven Karl [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kimpland, Robert Herbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-07

    Design and performance of a proposed LEU burst reactor are sketched. Salient conclusions reached are the following: size would be ~1,500 kg or greater, depending on the size of the central cavity; internal stresses during burst require split rings for relief; the reactor would likely require multiple control and safety rods for fine control; the energy spectrum would be comparable to that of HEU machines; and burst yields and steady-state power levels will be significantly greater in an LEU reactor.

  17. Random processes in nuclear reactors

    CERN Document Server

    Williams, M M R

    1974-01-01

    Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources

  18. Safety of VVER-440 reactors

    CERN Document Server

    Slugen, Vladimir

    2011-01-01

    Safety of VVER-440 Reactors endeavours to promote an increase in the safety of VVER-440 nuclear reactors via the improvement of fission products limitation systems and the implementation of special non-destructive spectroscopic methods for materials testing. All theoretical and experimental studies performed the by author over the last 25 years have been undertaken with the aim of improving VVER-440 defence in depth, which is one of the most important principle for ensuring safety in nuclear power plants. Safety of VVER-440 Reactors is focused on the barrier system through which the safety pri

  19. BR2 reactor neutron beams

    International Nuclear Information System (INIS)

    The use of reactor neutron beams is becoming increasingly more widespread for the study of some properties of condensed matter. It is mainly due to the unique properties of the ''thermal'' neutrons as regards wavelength, energy, magnetic moment and overall favorable ratio of scattering to absorption cross-sections. Besides these fundamental reasons, the impetus for using neutrons is also due to the existence of powerful research reactors (such as BR2) built mainly for nuclear engineering programs, but where a number of intense neutron beams are available at marginal cost. A brief introduction to the production of suitable neutron beams from a reactor is given. (author)

  20. Nuclear reactor PBMR and cogeneration; Reactor nuclear PBMR y cogeneracion

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez S, J. R.; Alonso V, G., E-mail: ramon.ramirez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2013-10-15

    In recent years the nuclear reactor designs for the electricity generation have increased their costs, so that at the moment costs are managed of around the 5000 US D for installed kw, reason for which a big nuclear plant requires of investments of the order of billions of dollars, the designed reactors as modular of low power seek to lighten the initial investment of a big reactor dividing the power in parts and dividing in modules the components to lower the production costs, this way it can begin to build a module and finished this to build other, differing the long term investment, getting less risk therefore in the investment. On the other hand the reactors of low power can be very useful in regions where is difficult to have access to the electric net being able to take advantage of the thermal energy of the reactor to feed other processes like the water desalination or the vapor generation for the processes industry like the petrochemical, or even more the possible hydrogen production to be used as fuel. In this work the possibility to generate vapor of high quality for the petrochemical industry is described using a spheres bed reactor of high temperature. (Author)

  1. Reactor Safety Commission Code of Practice for Pressurized Water Reactors

    International Nuclear Information System (INIS)

    The Reactor Safety Commission of the Federal German Republic has summarized in the form of Official Guidelines the safety requirements which, in the Commission's view, have to be met in the design, construction and operation of a nuclear power station equipped with a pressurized water reactor. The Third Edition of the RSK Guidelines for pressurized water reactors dated 14.10.81. is a revised and expanded version of the Second Edition dated 24.1.79. The Reactor Safety Commission will with effect from October 1981 use these Guidelines in consultations on the siting of and safety concept for the installation approval of future pressurized water reactors and will assess these nuclear power stations during their erection in the light of these Guidelines. They have not however been immediately conceived for the adaptation of existing nuclear power stations, whether under construction or in operation. The scope of application of these Guidelines to such nuclear power stations will have to be examined for each individual case. The main aim of the Guidelines is to simplify the consultation process within the reactor Safety Commission and to provide early advice on the safety requirements considered necessary by the Commission. (author)

  2. Breeder Reactors, Understanding the Atom Series.

    Science.gov (United States)

    Mitchell, Walter, III; Turner, Stanley E.

    The theory of breeder reactors in relationship to a discussion of fission is presented. Different kinds of reactors are characterized by the cooling fluids used, such as liquid metal, gas, and molten salt. The historical development of breeder reactors over the past twenty-five years includes specific examples of reactors. The location and a brief…

  3. FASTER test reactor preconceptual design report summary

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Belch, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Heidet, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Hill, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hoffman, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Jin, E. [Argonne National Lab. (ANL), Argonne, IL (United States); Mohamed, W. [Argonne National Lab. (ANL), Argonne, IL (United States); Moisseytsev, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Passerini, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Sumner, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Vilim, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Hayes, Steven [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-29

    The FASTER reactor plant is a sodium-cooled fast spectrum test reactor that provides high levels of fast and thermal neutron flux for scientific research and development. The 120MWe FASTER reactor plant has a superheated steam power conversion system which provides electrical power to a local grid allowing for recovery of operating costs for the reactor plant.

  4. Research reactors: design, safety requirements and applications

    International Nuclear Information System (INIS)

    There are two types of reactors: research reactors or power reactors. The difference between the research reactor and energy reactor is that the research reactor has working temperature and fuel less than the power reactor. The research reactors cooling uses light or heavy water and also research reactors need reflector of graphite or beryllium to reduce the loss of neutrons from the reactor core. Research reactors are used for research training as well as testing of materials and the production of radioisotopes for medical uses and for industrial application. The difference is also that the research reactor smaller in terms of capacity than that of power plant. Research reactors produce radioactive isotopes are not used for energy production, the power plant generates electrical energy. In the world there are more than 284 reactor research in 56 countries, operates as source of neutron for scientific research. Among the incidents related to nuclear reactors leak radiation partial reactor which took place in three mile island nuclear near pennsylvania in 1979, due to result of the loss of control of the fission reaction, which led to the explosion emitting hug amounts of radiation. However, there was control of radiation inside the building, and so no occurred then, another accident that lead to radiation leakage similar in nuclear power plant Chernobyl in Russia in 1986, has led to deaths of 4000 people and exposing hundreds of thousands to radiation, and can continue to be effect of harmful radiation to affect future generations. (author)

  5. Conceptual design study of JSFR reactor building

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, T.; Katoh, A.; Chikazawa, Y. [Japan Atomic Energy Agency (JAEA), 4002 Narita, Oarai, Ibaraki 311-1393 (Japan); Ohya, T.; Iwasaki, M.; Hara, H.; Akiyama, Y. [Mitsubishi FBR Systems, Inc. MFBR, 34-17, Jingumae 2-chome, Shibuya, Tokyo 150-0001 (Japan)

    2012-07-01

    Japan Sodium-cooled Fast Reactor (JSFR) is planning to adopt the new concepts of reactor building. One is that the steel plate reinforced concrete is adopted for containment vessel and reactor building. The other is the advanced seismic isolation system. This paper describes the detail of new concepts for JSFR reactor building and engineering evaluation of the new concepts. (authors)

  6. FASTER test reactor preconceptual design report summary

    International Nuclear Information System (INIS)

    The FASTER reactor plant is a sodium-cooled fast spectrum test reactor that provides high levels of fast and thermal neutron flux for scientific research and development. The 120MWe FASTER reactor plant has a superheated steam power conversion system which provides electrical power to a local grid allowing for recovery of operating costs for the reactor plant.

  7. Light water reactor safety research

    International Nuclear Information System (INIS)

    As the technology of light water reactors (LWR) was being commercialized, the German Federal Government funded the reactor safety research program, which was conducted by national research centers, universities, and industry, and which led to the establishment, in early 1972, of the Nuclear Safety Project in Karlsruhe. In the seventies, the PNS project mainly studied the loss-of-coolant accident. Numerous experiments were run and computer codes developed for this purpose. In the eighties, the Karlsruhe Nuclear Research Center contributed to the German Risk Study, investigating especially core meltdown accidents under the impact of the events at Three Mile Island-2 and Chernobyl-4. Safety research in the nineties is concentrated on the requirements of future reactor generations, such as the European Pressurized Water Reactor (EPR) or potential approaches which, at the present time, are discernible only as tentative theoretical designs. (orig.)

  8. Reactor operation environmental information document

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, L.R.; Hayes, D.W.; Hunter, C.H.; Marter, W.L.; Moyer, R.A.

    1989-12-01

    This volume is a reactor operation environmental information document for the Savannah River Plant. Topics include meteorology, surface hydrology, transport, environmental impacts, and radiation effects. 48 figs., 56 tabs. (KD)

  9. Fuel for advanced CANDU reactors

    International Nuclear Information System (INIS)

    The CANDU reactor system has proven itself to be a world leader in terms of station availability and low total unit energy cost. In 1985 for example, four of the top ten reactor units in the world were CANDU reactors operating in South Korea and Canada. This excellent operating record requires an equivalent performance record of the low-cost, natural uranium fuel. Future CANDU reactors will be an evolution of the present design. Engineering work is under way to refine the existing CANDU 600 and to incorporate state-of-the-art technology, reducing the capital cost and construction schedule. In addition, a smaller CANDU 300 plant has been designed using proven CANDU 600 technology and components but with an innovative new plant layout that makes it cost competitive with coal fired plants. For the long term, work on advanced fuel cycles and major system improvements is underway ensuring that CANDU plants will stay competitive well into the next century

  10. Conceptual design of RFC reactor

    International Nuclear Information System (INIS)

    A parametic analysis and a preliminary conceptual design for RFC reactor (including cusp field) with and without alpha particle heating are described. Steady state operations can be obtained for various RF ponderomotive potential in cases of alpha particle heating. (author)

  11. Methanogenesis in Thermophilic Biogas Reactors

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær

    1995-01-01

    against Methanothrix soehngenii or Methanothrix CALS-I in any of the thermophilic biogas reactors examined. Studies using 2-14C-labeled acetate showed that at high concentrations (more than approx. 1 mM) acetate was metabolized via the aceticlastic pathway, transforming the methyl-group of acetate...... microorganism into methane. In thermophilic biogas reactors,, acetate oxidizing cultures occupied the niche of Methanothrix species, aceticlastic methanogens which dominate at low acetate concentrations in mesophilic systems. Normally, thermophilic biogas reactors are operated at temperatures from 52 to 560 C....... Experiments using biogas reactors fed with cow manure showed that the same biogas yield found at 550 C could be obtained at 610 C after a long adaptation period. However, propionate degradation was inhibited by increasing the temperature....

  12. Teaching About Nature's Nuclear Reactors

    CERN Document Server

    Herndon, J M

    2005-01-01

    Naturally occurring nuclear reactors existed in uranium deposits on Earth long before Enrico Fermi built the first man-made nuclear reactor beneath Staggs Field in 1942. In the story of their discovery, there are important lessons to be learned about scientific inquiry and scientific discovery. Now, there is evidence to suggest that the Earth's magnetic field and Jupiter's atmospheric turbulence are driven by planetary-scale nuclear reactors. The subject of planetocentric nuclear fission reactors can be a jumping off point for stimulating classroom discussions about the nature and implications of planetary energy sources and about the geomagnetic field. But more importantly, the subject can help to bring into focus the importance of discussing, debating, and challenging current thinking in a variety of areas.

  13. RA reactor operation and maintenance

    International Nuclear Information System (INIS)

    This volume includes the final report on RA reactor operation and utilization of the experimental facilities in 1962, detailed analysis of the system for heavy water distillation and calibration of the system for measuring the activity of the air

  14. Technique of nuclear reactors controls

    International Nuclear Information System (INIS)

    This report deal about 'Techniques of control of the nuclear reactors' in the goal to achieve the control of natural uranium reactors and especially the one of Saclay. This work is mainly about the measurement into nuclear parameters and go further in the measurement of thermodynamic variables,etc... putting in relief the new features required on behalf of the detectors because of their use in the thermal neutrons flux. In the domain of nuclear measurement, we indicate the realizations and the results obtained with thermal neutron detectors and for the measurement of ionizations currents. We also treat the technical problem of the start-up of a reactor and of the reactivity measurement. We give the necessary details for the comprehension of all essential diagrams and plans put on, in particular, for the reactor of Saclay. (author)

  15. Jules Horowitz Reactor, basic design

    Energy Technology Data Exchange (ETDEWEB)

    Bergamaschi, Y.; Bouilloux, Y.; Chantoin, P.; Guigon, B.; Bravo, X.; Germain, C.; Rommens, M.; Tremodeux, P

    2003-07-01

    Since the shutdown of the SILOE reactor in 1997, the OSIRIS reactor has ensured the needs regarding technological irradiation at CEA including those of its industrial partners and customers. The Jules Horowitz Reactor will replace it. It has the ambition to provide the necessary nuclear data and maintain a fission research capacity in Europe after 2010. This capacity should be service-oriented. It will be established in Cadarache. The Jules Horowitz reactor will also: - represent a significant step in term of performances and experimental capabilities, - be designed with a high flexibility, in order to satisfy the current demand from European industry, research and be able to accommodate future requirements, - reach a high level of safety, according to the best current practice. This paper will present the main functionalities and the design options resulting from the 'preliminary design' studies. (authors)

  16. Unique features of space reactors

    Science.gov (United States)

    Buden, David

    Space reactors are designed to meet a unique set of requirements; they must be sufficiently compact to be launched in a rocket to their operational location, operate for many years without maintenance and servicing, operate in extreme environments, and reject heat by radiation to space. To meet these restrictions, operating temperatures are much greater than in terrestrial power plants, and the reactors tend to have a fast neutron spectrum. Currently, a new generation of space reactor power plants is being developed. The major effort is in the SP-100 program, where the power plant is being designed for seven years of full power, and no maintenance operation at a reactor outlet operating temperature of 1350 K.

  17. Advanced Catalytic Hydrogenation Retrofit Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Reinaldo M. Machado

    2002-08-15

    Industrial hydrogenation is often performed using a slurry catalyst in large stirred-tank reactors. These systems are inherently problematic in a number of areas, including industrial hygiene, process safety, environmental contamination, waste production, process operability and productivity. This program proposed the development of a practical replacement for the slurry catalysts using a novel fixed-bed monolith catalyst reactor, which could be retrofitted onto an existing stirred-tank reactor and would mitigate many of the minitations and problems associated with slurry catalysts. The full retrofit monolith system, consisting of a recirculation pump, gas/liquid ejector and monolith catalyst, is described as a monolith loop reactor or MLR. The MLR technology can reduce waste and increase raw material efficiency, which reduces the overall energy required to produce specialty and fine chemicals.

  18. Advanced Carbothermal Electric Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop the Advanced Carbothermal Electric (ACE) reactor to efficiently extract oxygen from lunar regolith. Unlike state-of-the-art carbothermal...

  19. Advanced Carbothermal Electric Reactor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall objective of the Phase 1 effort was to demonstrate the technical feasibility of the Advanced Carbothermal Electric (ACE) Reactor concept. Unlike...

  20. Gas-cooled fast breeder reactor

    International Nuclear Information System (INIS)

    Almost all the R D works of gas-cooled fast breeder reactor in the world were terminated at the end of the year 1980. In order to show that the R D termination was not due to technical difficulties of the reactor itself, the present paper describes the reactor plant concept, reactor performances, safety, economics and fuel cycle characteristics of the reactor, and also describes the reactor technologies developed so far, technological problems remained to be solved and planned development schedules of the reactor. (author)

  1. Solid State Reactor Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas

  2. Material test reactor fuel research at the BR2 reactor

    International Nuclear Information System (INIS)

    The construction of new, high performance material test reactor or the conversion of such reactors' core from high enriched uranium (HEU) to low enriched uranium (LEU) based fuel requires several fuel qualification steps. For the conversion of high performance reactors, high density dispersion or monolithic fuel types are being developed. The Uranium-Molybdenum fuel system has been selected as reference system for the qualification of LEU fuels. For reactors with lower performance characteristics, or as medium enriched fuel for high performance reactors, uranium silicide dispersion fuel is applied. However, on the longer term, the U-Mo based fuel types may offer a more efficient fuel alternative and-or an easier back-end solution with respect to the silicide based fuels. At the BR2 reactor of the Belgian nuclear research center, SCK-CEN in Mol, several types of fuel testing opportunities are present to contribute to such qualification process. A generic validation test for a selected fuel system is the irradiation of flat plates with representative dimensions for a fuel element. By flexible positioning and core loading, bounding irradiation conditions for fuel elements can be performed in a standard device in the BR2. For fuel element designs with curved plates, the element fabrication method compatibility of the fuel type can be addressed by incorporating a set of prototype fuel plates in a mixed driver fuel element of the BR2 reactor. These generic types of tests are performed directly in the primary coolant flow conditions of the BR2 reactor. The experiment control and interpretation is supported by detailed neutronic and thermal-hydraulic modeling of the experiments. Finally, the BR2 reactor offers the flexibility for irradiation of full size prototype fuel elements, as 200mm diameter irradiation channels are available. These channels allow the accommodation of various types of prototype fuel elements, eventually using a dedicated cooling loop to provide the

  3. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Iwashige, Kengo

    1996-06-21

    In an LMFBR type reactor, partitions are disposed to a coolant channel at positions lower than the free liquid level, and the width of the partitions is adapted to have a predetermined condition. Namely, when low temperature fluid overflowing the wall of the coolant channel, flows down and collided against the free liquid surface in the coolant channel, since the dropping speed thereof is reduced abruptly, large pressure waves are caused by kinetic force of the low temperature fluid. However, if appropriate numbers of partitions having an appropriate shape are formed, the dropping speed of the low temperature fluid is moderated to reduce the pressure waves. In addition, since the pressure waves are dispersed to the circumferential and lateral directions of the coolant flow channel respectively, the propagation of the pressure waves can be prevented effectively. Further, when the flow of the low temperature fluid is changed to the circumferential direction, for example, by earthquakes, since the partitions act as members resisting against the circumferential change of the low temperature fluid, the change of the direction can be suppressed. (N.H.)

  4. Natural convection type reactor

    International Nuclear Information System (INIS)

    In a natural convection type nuclear reactor, recycling flow rate of coolants is increased and the amount of entrained bubbles are increased as the driving force is increased, so that bubbles are not separated completely even if a stagnation region is disposed. Then, a space opened only at the upper portion is disposed at the outer circumference of the upper end of a riser for storing overflown coolants temporarily. The flow of coolants incorporating steam bubbles uprising in the riser turns into the horizontal direction at the upper end of the riser wall and flows into the coolant reservoir. In the coolant reservoir, since the momentum of the coolants is lost and the flow is stagnated, the bubbles are easily released to the upper space. Coolants, after releasing the bubbles, further overflow and descend in the downcomer. Then, the bubbles can be separated undergoing no influence of the driving force caused as the sum of the uprising force in the riser and the water head pressure in the downcomer, to prevent increase of carry under due to increase of the driving force. (N.H.)

  5. Reactor Simulator Testing Overview

    Science.gov (United States)

    Schoenfeld, Michael P.

    2013-01-01

    Test Objectives Summary: a) Verify operation of the core simulator, the instrumentation & control system, and the ground support gas and vacuum test equipment. b) Examine cooling & heat regeneration performance of the cold trap purification. c) Test the ALIP pump at voltages beyond 120V to see if the targeted mass flow rate of 1.75 kg/s can be obtained in the RxSim. Testing Highlights: a) Gas and vacuum ground support test equipment performed effectively for operations (NaK fill, loop pressurization, and NaK drain). b) Instrumentation & Control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings and ramped within prescribed constraints. It effectively interacted with reactor simulator control model and defaulted back to temperature control mode if the transient fluctuations didn't dampen. c) Cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the minimum temperature indicating the design provided some heat regeneration. d) ALIP produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  6. Reactor Simulator Testing

    Science.gov (United States)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise J.

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  7. Novel Catalytic Membrane Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  8. OECD Halden Reactor Project

    International Nuclear Information System (INIS)

    The OECD Halden Reactor Project is both the oldest and the only one still in operation of the three major joint undertakings established at the inception of the OECD Nuclear Energy Agency. This publication has been printed in connection with its twenty-fifth anniversary as an international project. After presentation of the history and organization of the project, a thorough description of the past and present activities in the field of fuel performance and process control and surveillance is given. The projects's fuel testing programme is now focuessed on an investigation to define safety margins under normal operations as well as under various kinds of accident situations. Fuel research is also concerned with the characterisation of long term effects with regard to efficiency, operational safety and mapping of reliability and durability in the case of accidents with loss of coolant. In the field of process control and surveillance, research work is directly linked to the use of computers and colour graphics as tools in the control room. A fullscale simulator-based model and experimental control room has been constructed. The first experiments to be carried out in this laboratory will investigate the advantage of analysing alarms before they are presented to the operator. (RF)

  9. Nuclear reactor container

    International Nuclear Information System (INIS)

    A gas containing vessel has a water pool which is in communication with a dry well containing a reactor pressure vessel by way of a communication pipe is disposed. A capacity of a gas phase portion of the gas containing chamber, a capacity of the dry well, a water depth of a bent tube communicating the dry well with a pressure suppression pool of a pressure suppression chamber and a water depth of the communication pipe are determined so as to satisfy specific conditions. Since the water depth of the communication pipe is less than the water depth of the bent tube, incondensible gases and steams in the dry well flow into the water pool of the gas containing chamber at the initial stage of loss of coolant accident. Subsequently, steams in the dry well flow into the pressure suppression pool of the pressure suppression chamber by way of the bent tube. Accordingly, since the incondensible gases in the dry well do not flow into the pressure suppression chamber, pool swelling phenomenon in the pressure suppression chamber is not caused even if the water depth of the bent tube which leads to the pressure suppression chamber is great. Further, pressure increase due to transfer of the incondensible gases is decreased. (I.N.)

  10. OECD Halden reactor project

    International Nuclear Information System (INIS)

    A major part of the current research programme is devoted to irradiation experiments with a wide variety of heavily instrumented test fuel assemblies, in order to study the thermal and mechanical behavior of fuel rods through in-core measurements, in particular various forms of deformation of cladding and fuel as related to operational conditions and fuel rod design parameters. From these measurements mathematical models are being developed to explain quantitatively the deformation behavior, as well as the thermal properties of the fuel. During 1974, fifty-six instrumented fuel assemblies were irradiated in these experiments. Another major part of the Halden programme is aimed at the development and demonstration of advanced computer-based methods for plant and reactor core control, for safety and protection, and for overall supervision of nuclear power stations. Both the control methods themselves and the associated measurement and control apparatus are being elaborated, and during the year particular progress was made with the ''OPCOM'' process operator communication system

  11. MOLTEN FLUORIDE NUCLEAR REACTOR FUEL

    Science.gov (United States)

    Barton, C.J.; Grimes, W.R.

    1960-01-01

    Molten-salt reactor fuel compositions consisting of mixtures of fluoride salts are reported. In its broadest form, the composition contains an alkali fluoride such as sodium fluoride, zirconium tetrafluoride, and a uranium fluoride, the latter being the tetrafluoride or trifluoride or a mixture of the two. An outstanding property of these fuel compositions is a high coeffieient of thermal expansion which provides a negative temperature coefficient of reactivity in reactors in which they are used.

  12. Meeting on reactor safety research

    International Nuclear Information System (INIS)

    The meeting 'Reactor Safety Research' organized for the second time by the GRS by order of the BMFT gave a review of research activities on the safety of light water reactors in the Federal Repulbic of Germany, international co-operation in this field and latest results of this research institution. The central fields of interest were subjects of man/machine-interaction, operational reliability accident sequences, and risk. (orig.)

  13. Fractals in Power Reactor Noise

    International Nuclear Information System (INIS)

    In this work the non- lineal dynamic problem of power reactor is analyzed using classic concepts of fractal analysis as: attractors, Hausdorff-Besikovics dimension, phase space, etc. A new non-linear problem is also analyzed: the discrimination of chaotic signals from random neutron noise signals and processing for diagnosis purposes. The advantages of a fractal analysis approach in the power reactor noise are commented in details

  14. Stellarator fusion reactors - an overview

    International Nuclear Information System (INIS)

    The stellarator system offers a distinct alternative to the mainline approaches to magnetic fusion power and has several potentially major advantages. Since the first proposal of the stellarator concept many reactor studies have been published and these studies reflect the large variety of stellarator configurations. The main representatives are the continuous-coil configurations and the modular-coil configurations. As a continuation of the LHD experiment two reactor configurations, FFHR1 and FFHR2, have been investigated, which use continuous helical windings for providing the magnetic field. The modular coil concept has been realized in the MHH-reactor study (USA 1997) and in the Helias reactor. The Helias reactor combines the principle of plasma optimisation with a modular coil system. The paper also discusses the issues associated with the blanket and the maintenance process. Stellarator configurations with continuous coils such as LHD possess a natural helical divertor, which can be used favourably for impurity control. In advanced stellarators with modular coils the same goal can be achieved by the island divertor. Plasma parameters in the various stellarator reactors are computed on the basis of presently known scaling laws showing that confinement is sufficiently good to provide ignition and self-sustained burn. (author)

  15. Materials requirements for fusion reactors

    International Nuclear Information System (INIS)

    Once the physics of fusion devices is understood, one or more experimental power reactors (EPR) are planned which will produce net electrical power. The structural material for the device will probably be a modification of an austenitic stainless steel. Unlike fission reactors, whose pressure boundaries are subjected to no or only light irradiation, the pressure boundary of a fusion reactor is subjected to high atomic displacement-damage and high production rates of transmutation products, e.g., helium and hydrogen. The design data base must include irradiated materials. Since in situ testing to obtain tensile, fatigue, creep, crack-growth, stress-rupture, and swelling data is currently impossible for fusion reactor conditions, a program of service-temperature irradiations in fission reactors followed by postirradiation testing, simulation of fusion conditions, and low-fluence 14 MeV neutron-irradiation tests are planned. For the Demonstration Reactor (DEMO) expected to be built within ten years after theEPR, higher heat fluxes may require the use of refractory metals, at least for the first 20 cm. A partial data base may be provided by high-flux 14 MeV neutron sources being planned. Many materials other than those for structural components will be required in the EPR and DEMO. These include superconducting magnets, insulators, neutron reflectors and shields, and breeding materials. The rest of the device should utilize conventional materials except that portion involved in tritium confinement and recovery

  16. The safety of light water reactors

    International Nuclear Information System (INIS)

    The book describes the principles and practices of reactor safety as applied to the design, regulation and operation of both pressurized water reactors and boiling water reactors. The central part of the book is devoted to methods and results of safety analysis. Some significant events are described, notably the Three Mile Island accident. The book concludes with a chapter on the PIUS principle of inherent reactor safety as applied to the SECURE type of reactor developed in Sweden. (G.B.)

  17. Three dimensional diffusion calculations of nuclear reactors

    International Nuclear Information System (INIS)

    This work deals with the three dimensional calculation of nuclear reactors using the code TRITON. The purposes of the work were to perform three-dimensional computations of the core of the Soreq nuclear reactor and of the power reactor ZION and to validate the TRITON code. Possible applications of the TRITON code in Soreq reactor calculations and in power reactor research are suggested. (H.K.)

  18. ICONE-4: Proceedings. Volume 2: Advanced reactors

    International Nuclear Information System (INIS)

    The proceedings for this conference are contained in 5 volumes. This volume is divided into the following areas: advanced reactor requirements; advanced reactor design and analysis; arrangement and construction; specific reactor designs; demonstration testing; safety systems and analysis; component demonstration testing; advanced reactor containment design; licensing topics and updates; accelerator applications and spallation sources; and advanced reactor development. Separate abstracts were prepared for most papers in this volume

  19. Molten-Salt Depleted-Uranium Reactor

    OpenAIRE

    Dong, Bao-Guo; Dong, Pei; Gu, Ji-Yuan

    2015-01-01

    The supercritical, reactor core melting and nuclear fuel leaking accidents have troubled fission reactors for decades, and greatly limit their extensive applications. Now these troubles are still open. Here we first show a possible perfect reactor, Molten-Salt Depleted-Uranium Reactor which is no above accident trouble. We found this reactor could be realized in practical applications in terms of all of the scientific principle, principle of operation, technology, and engineering. Our results...

  20. Calculation of reactor antineutrino spectra in TEXONO

    CERN Document Server

    Chen Dong Liang; Mao Ze Pu; Wong, T H

    2002-01-01

    In the low energy reactor antineutrino physics experiments, either for the researches of antineutrino oscillation and antineutrino reactions, or for the measurement of abnormal magnetic moment of antineutrino, the flux and the spectra of reactor antineutrino must be described accurately. The method of calculation of reactor antineutrino spectra was discussed in detail. Furthermore, based on the actual circumstances of NP2 reactors and the arrangement of detectors, the flux and the spectra of reactor antineutrino in TEXONO were worked out

  1. Analysis of higher power research reactors' parameters

    International Nuclear Information System (INIS)

    The objective of this monograph was to analyze and compare parameters of different types of research reactors having higher power. This analysis could be used for decision making and choice of a reactor which could possibly replace the existing ageing RA reactor in Vinca. Present experimental and irradiation needs are taken into account together with the existing reactors operated in our country, RB and TRIGA reactor

  2. Impact of proposed research reactor standards on reactor operation

    International Nuclear Information System (INIS)

    A Standards Committee on Operation of Research Reactors, (ANS-15), sponsored by the American Nuclear Society, was organized in June 1971. Its purpose is to develop, prepare, and maintain standards for the design, construction, operation, maintenance, and decommissioning of nuclear reactors intended for research and training. Of the 15 original members, six were directly associated with operating TRIGA facilities. This committee developed a standard for the Development of Technical Specifications for Research Reactors (ANS-15.1), the revised draft of which was submitted to ANSI for review in May of 1973. The Committee then identified 10 other critical areas for standards development. Nine of these, along with ANS-15.1, are of direct interest to TRIGA owners and operators. The Committee was divided into subcommittees to work on these areas. These nine areas involve proposed standards for research reactors concerning: 1. Records and Reports (ANS-15.3) 2. Selection and Training of Personnel (ANS-15.4) 3. Effluent Monitoring (ANS-15.5) 4. Review of Experiments (ANS-15.6) 5. Siting (ANS-15.7) 6. Quality Assurance Program Guidance and Requirements (ANS-15.8) 7. Restrictions on Radioactive Effluents (ANS-15.9) 8. Decommissioning (ANS-15.10) 9. Radiological Control and Safety (ANS-15.11). The present status of each of these standards will be presented, along with their potential impact on TRIGA reactor operation. (author)

  3. Prometheus Project Reactor Module Final Report, For Naval Reactors Information

    International Nuclear Information System (INIS)

    The Naval Reactors Prime Contractor Team (NRPCT) led the development of a power plant for a civilian nuclear electric propulsion (NEP) system concept as part of the Prometheus Project. This report provides a summary of the facts, technical insights, and programmatic perspectives gained from this two-year program. The Prometheus Project experience has been extensively documented to better position the US for future space reactor development. Major Technological and engineering challenges exist to develop a system that provides useful electric power from a nuclear fission heat source operating in deep space. General issues include meeting mission requirements in a system that has a mass low enough to launch from earth while assuring public safety and remaining safely shutdown during credible launch accidents. These challenges may be overcome in the future if there is a space mission with a compelling need for nuclear power to drive development. Past experience and notional mission requirements indicate that any useful space reactor system will be unlike past space reactors and existing terrestrial reactors

  4. Repairing liner of the reactor; Reparacion del liner del reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-07-15

    Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

  5. Operating experiences of the research reactors

    International Nuclear Information System (INIS)

    Nuclear research reactors are devices of wide importance, being used for different scientific research tasks, for testing and improving reactor systems and components, for the production of radioisotopes, for the purposes of defence, for staff training and for other purposes. There are three research reactors in Yugoslavia: RA, RB and TRIGA. Reactors RA and RB at the 'Boris Kidric' Institute of Nuclear Sciences are of heavy water type power being 6500 and 10 kW, and maximum thermal neutron flux of 1014 and 1011(n/cm2s), respectively. TRIGA reactor at the 'Jozef Stefan' Institute in Ljubljana is of 250 kW power and maximum thermal neutron flux of 1013(n/cm2s). Reactors RA and RB use soviet fuel in the form of uranium dioxide (80% enriched) and metallic uranium (2%). Besides, RB reactor operates with natural uranium too. TRIGA reactor uses american uranium fuel 70% and 20% enriched, uranium being mixed homogeneously with moderator (ZrH). Experiences in handling and controlling the fuel before irradiation in the reactor, in reactor and after it are numerous and valuable, involving either the commercial arrangements with foreign producers, or optimal burn up in reactor or fuel treatment after the reactor irradiation. Twenty years of operating experience of these reactors have great importance especially having in mind the number of trained staff. Maintenance of reactors systems and fluids in continuous operation is valuable experience from the point of view of water reactor utilization. The case of the RA reactor primary cycle cobalt decontamination and other events connected with nuclear and radiation security for all three reactors are also specially emphasized. Owing to our research reactors, numerous theoretical, numerical and experimental methods are developed for nuclear and other analyses and design of research and power reactors,as well as methods for control and protection of radiation. (author)

  6. Establishment of licensing process for development reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Jong Chull; Yune, Young Gill; Kim, Woong Sik (and others)

    2006-02-15

    A study on licensing processes for development reactors has been performed to prepare the licensing of development reactors developed in Korea. The contents and results of the study are summarized as follows. The licensing processes for nuclear reactors in Korea, U.S.A., Japan, France, U.K., Canada, and IAEA were surveyed and analyzed to obtain technical bases necessary for establishing licensing processes applicable to development reactors in Korea. Based on the technical bases obtained the above analysis, the purpose, power output, and design characteristics of development reactors were analyzed in detail. The analysis results suggested that development reactors should be classified as a new reactor category (called as 'development reactor') separated from the current reactor categories such as the research reactor and the power reactor. Therefore, it is proposed to establish a new reactor category classified as 'development reactor' for the development reactors. And licensing processes, including licensing technical requirements, licensing document requirements, and other regulatory requirements, were also proposed for the development reactors. In order to institutionalize the licensing processes developed in this study, it is necessary to revise the current laws. Therefore, draft provisions of Atomic Energy Act, Enforcement Decree of the Atomic Energy Act, and Enforcement Regulation of the Atomic Energy Act have been developed for the preparation of the future legalization of the licensing processes proposed for the development reactors. Conclusively, a proposal of licensing processes and draft provisions of laws have been developed for the development reactors. The results proposed in this study can be applied directly to the licensing of the future development reactors. Furthermore, they will also contribute to establishing successfully the licensing processes of the development reactors.

  7. Nordic study on reactor waste

    International Nuclear Information System (INIS)

    In 1981, 14 nuclear power reactors are in operation and 2 under construction in the Nordic countries. So far, the reactor waste originating from day-to-day operation of these plants has been stored in solidified form at the reactor sites. Within a few years a satisfactory disposal procedure needs to be established. While the main R and D effects in the waste field have earlier been devoted to the question of irradiated fuel and waste from reprocessing, there is therefore now an increased interest in reactor waste with its much lower radioactivity but somewhat larger volumes. Since 1977, efforts have been made in a joint Nordic study to examine which facts need to be known in order to perform a comprehensive safety assessment of a reactor waste management system. In the present study a Reference system related to the waste generated over 30 years from six 500 MW-reactors is examined. The dominating radionuclides during storage and transportation accident scenarios are Cs-134, Cs-137 and Co-60. For most of the release scenarios from repositories Cs-137 and Sr-90 are dominating. Some scenarios are, however, dominated by the very longlived nuclides I-129 and C-14. A closer examination of the concentration in the waste of these nuclides and of their leaching properties indicates that their small - but significant - influence, as calculated, is probably grossly overestimated. The mechanical stability obtained in routine solidification processes of reactor waste products in conjunction with the outer container (steel drum, transport container, etc.) turns out to be sufficient. Difficulties were encountered in applying ICRP methodology and available dose calculation methods to calculation of population doses due to small activity releases, and effects extending into the far future. (EG)

  8. When reactors reach old age

    International Nuclear Information System (INIS)

    While the battle over whether to build new nuclear plants has quieted in recent times, a second struggle is shaping up in the United States as reactors approach a new stage of life: retirement. Four decades into the nuclear power age, questions of how best to dismantle and dispose of a nuclear power plant remain largely unanswered. The debates have been mainly academic until now - although reactors have operated for 25 years, decommissioning retired reactors has simply not been fully planned in this country. But the Shippingport Atomic Power Station in Pennsylvania, the first large-scale power reactor to be retired, is now being decommissioned. The work has rekindled the debates in the light of reality. Outside the United States, decommissioning is also being confronted on a new plane. Virtually all groups involved in decommissioning a reactor in the United States - the utility, the Nuclear Regulatory Commission, the U.S. Department of Energy, the U.S. Environmental Protection Agency, state public service commissions, and citizen organizations - agree that for the most part the technology to dismantle and dispose of a reactor safely is available. They disagree, however, on which technical option is the safest or cheapest and on who should pay for dismantlement. And there are further complications: Which regulations must be complied with. How much radiation exposure for workers and the public is acceptable. Even with answers to these questions, uncertainty about where to dispose of the radioactive waste and about how much residual radiation can be left at a former reactor site plagues the architects of decommissioning. This article discusses these questions

  9. Market introduction of innovative reactors

    International Nuclear Information System (INIS)

    Besides the development of evolutionary and passive LWR, also that of innovative reactors is attractive, because other applications (new markets) besides base load electricity generation can be thought of, and interesting new features on the area of safety or waste incineration can be shown. For market introduction however, a (partial) new infrastructure and a demonstration plant are required. Taking the abundance of fossil fuels and the accompanying low fuel prices today and in the near future into account, the funds to finance this will only become available when 1)the projected energy generating costs will be substantially lower than those of today, and 2)the costs of market introduction (i.e. the demonstration plant and the required infrastructure) will be limited. Generally speaking, there are two ways to seek competitiveness of a reactor type: 1)application of economy of scale, and 2)simplification. In this paper, an example of the second possibility is pursued for an innovative reactor type. The HR1 is a 40 MWth high temperature gas cooled reactor for heat and power cogeneration, a simplified version of the German HTR Module. The power level is chosen so small that additional safety features become apparent. For example, after a total loss of coolant the fuel remains fully intact, even if the reactor shutdown system fails and the reactor goes critical again after a number of hours. These safety features are used to omit certain components, like the emergency core cooling system, or to select a cheaper version of components, e.g. replacing the containment building by a confinement. Moreover, degradation of the safety class of certain components comes within the realm of possibilities. The cost reduction offered by these two measures are used to more than offset the economy-of-scale disadvantage of this small reactor system. (author)

  10. University of Florida training reactor. Annual progress report, September 1, 1984-August 31, 1985

    International Nuclear Information System (INIS)

    This annual progress report of the University of Florida Training Reactor discusses: reactor operation; personnel; modifications made to the reactors; reactor maintenance; and testing of reactor systems

  11. Reactivity determination in accelerator driven reactors using reactor noise analysis

    Directory of Open Access Journals (Sweden)

    Kostić Ljiljana 1

    2002-01-01

    Full Text Available Feynman-alpha and Rossi-alpha methods are used in traditional nuclear reactors to determine the subcritical reactivity of a system. The methods are based on the measurement of the mean value, variance and the covariance of detector counts for different measurement times. Such methods attracted renewed attention recently with the advent of the so-called accelerator driven reactors (ADS proposed some time ago. The ADS systems, intended to be used either in energy generation or transuranium transmutation, will use a subcritical core with a strong spallation source. A spallation source has statistical properties that are different from those traditionally used by radioactive sources. In such reactors the monitoring of the subcritical reactivity is very important, and a statistical method, such as the Feynman-alpha method, is capable of resolving this problem.

  12. Fast Reactor Development Strategy in China

    International Nuclear Information System (INIS)

    As one of the largest developing countries, China needs a reliable energy supplement. At the same time, China should improve the energy structure to decrease CO2 emissions. Nuclear and renewable energies are the main solutions to these issues. According to the research results, the nuclear capacity should increase to 400 GW(e) up to 2050. Fast reactors must be developed considering the limitation of uranium resources. In order to deploy fast reactor technology, the ‘experimental reactor, demonstration reactor and commercial reactor’ strategy has been suggested. China has finished the construction of the China Experimental Fast Reactor (CEFR) and gained necessary experience about fast reactors. The China Institute of Atomic Energy (CIAE) has begun to design the CFR-600, a 600 MW(e) demonstration fast reactor. This reactor will be put into operation before 2025. After that, a larger commercial reactor will be constructed. Besides fast reactors, all of other key sectors of fuel cycle will be developed at the same time such as reprocessing, fast reactor fuel, etc. There are two main tasks of fast reactors, one of which is to raise the utility ratio of uranium, and the other one is to transmute the long life waste of light water reactors. The fast reactor will be designed as a breeder and burner, respectively. (author)

  13. Detailed lithologic log of the Dow Chemical #1 B.L. Garrigan Drill Hole, Mississippi County, Arkansas

    Science.gov (United States)

    Collins, Donley S.; Skipp, Gary L.

    1995-01-01

    The geology and tectonic setting of the New Madrid region in southeastern Missouri has received considerable attention because of the area's high seismic activity. The largest recorded earthquakes in this area occurred in the winter of 1811-1812. These earthquakes has estimated magnitudes as large as 8.0 on the Richter scale (Johnsonton and Kanter, 1990) and affected an area of about 1 million square miles (Fuller, 1912). Today, an area of continuously high seismic activity defines the New Madrid seismic zone, which extends from northeastern Arkansas into southeastern Missouri and northwestern Tennessee. Seismicity is locally concentrated along two subsurface archers--the Blytheville and Pascola (Hildenbrand and others, 1977; Crone and others, 1985; Hildenbrand, 1985; McKeown, 1988). The Padcola arch is not pertinent to this study and, therefore will not be discusses further. The Blytheville arch is located in and is subparallel to the axis of the northeast-southwest-trending Reelfoot structural basin, which formed during early Paleozoic rifting (Ervin and McGinnis, 1975; fig. 1). The Reelfoot basin is filled with Cambrian and Ordovician sedimentary rocks (Grohskopf, 1955; Howe, 1984; Houseknevht, 1989; Collins and others, 1992) that are uncomfortably overlain by Cretacaous and Tertiary sedimentary rocks and underlain by crystalline rocks of the eastern granite-rhyolite province (see Bickford and others, 1986). The presence of some Late Proterozoic sedimentary rocks in the Reelfoot basin currently cannot be ruled out. The Dow Chemical #1 B.L. Garrigan drill hole (hereafter, Garrigan) penetrated Paleozoic rocks on the Blytheville arch. The Garrigan is locted in the Reelfoot basin in the NW1/4, NW1/4 sec. 28, T. 15 N., R. 10 E., Mississippi County, Arkansas (fig. 1) and was completed to a total depth of 12,038 ft from a ground elevation of 239 ft on April 11, 1982 (Swolfs, 1991). The Garrigan is the only reported drill hole that penetrates the subsurface Blytheville

  14. Inherently safe light water reactors

    International Nuclear Information System (INIS)

    Today's large nuclear power reactors of world-wise use have been designed based on the philosophy. It seems that recent less electricity demand rates, higher capital cost and the TMI accident let us acknowledge relative small and simplified nuclear plants with safer features, and that Chernobyl accident in 1983 underlines the needs of intrinsic and passive safety characteristics. In such background, several inherently safe reactor concepts have been presented abroad and domestically. First describing 'Can inherently safe reactors be designed,' then I introduce representative reactor concepts of inherently safe LWRs advocated abroad so far. All of these innovative reactors employ intrinsic and passive features in their design, as follows: (1) PIUS, an acronym for Process Inherent Ultimate Safety, or an integral PWR with passive heat sink and passive shutdown mechanism, advocated by ASEA-ATOM of Sweden. (2) MAP(Minimum Attention Plant), or a self-pressurized, natural circulation integral PWR, promoted by CE Inc. of the U.S. (3) TPS(TRIGA Power System), or a compact PWR with passive heat sink and inherent fuel characteristics of large prompt temperature coefficient, prompted by GA Technologies Inc. of the U.S. (4) PIUS-BWR, or an inherently safe BWR employing passively actuated fluid valves, in competition with PIUS, prompted by ORNL of the U.S. Then, I will describe the domestic trends in Japan and the innovative inherently safe LWRs presented domestically so far. (author)

  15. Utilization of nuclear research reactors

    International Nuclear Information System (INIS)

    Full text: Report on an IAEA interregional training course, Budapest, Hungary, 5-30 November 1979. The course was attended by 19 participants from 16 Member States. Among the 28 training courses which the International Atomic Energy Agency organized within its 1979 programme of technical assistance was the Interregional Training Course on the Utilization of Nuclear Research Reactors. This course was held at the Nuclear Training Reactor (a low-power pool-type reactor) of the Technical University, Budapest, Hungary, from 5 to 30 November 1979 and it was complemented by a one-week Study Tour to the Nuclear Research Centre in Rossendorf near Dresden, German Democratic Republic. The training course was very successful, with 19 participants attending from 16 Member States - Bangladesh, Bolivia, Czechoslovakia, Ecuador, Egypt, India, Iraq, Korean Democratic People's Republic, Morocco, Peru, Philippines, Spain, Thailand, Turkey, Vietnam and Yugoslavia. Selected invited lecturers were recruited from the USA and Finland, as well as local scientists from Hungarian institutions. During the past two decades or so, many research reactors have been put into operation around the world, and the demand for well qualified personnel to run and fully utilize these facilities has increased accordingly. Several developing countries have already acquired small- and medium-size research reactors mainly for isotope production, research in various fields, and training, while others are presently at different stages of planning and installation. Through different sources of information, such as requests to the IAEA for fellowship awards and experts, it became apparent that many research reactors and their associated facilities are not being utilized to their full potential in many of the developing countries. One reason for this is the lack of a sufficient number of trained professionals who are well acquainted with all the capabilities that a research reactor can offer, both in research and

  16. Thermonuclear Reflect AB-Reactor

    CERN Document Server

    Bolonkin, Alexander

    2008-01-01

    The author offers a new kind of thermonuclear reflect reactor. The remarkable feature of this new reactor is a three net AB reflector, which confines the high temperature plasma. The plasma loses part of its energy when it contacts with the net but this loss can be compensated by an additional permanent plasma heating. When the plasma is rarefied (has a small density), the heat flow to the AB reflector is not large and the temperature in the triple reflector net is lower than 2000 - 3000 K. This offered AB-reactor has significantly less power then the currently contemplated power reactors with magnetic or inertial confinement (hundreds-thousands of kW, not millions of kW). But it is enough for many vehicles and ships and particularly valuable for tunnelers, subs and space apparatus, where air to burn chemical fuel is at a premium or simply not available. The author has made a number of innovations in this reactor, researched its theory, developed methods of computation, made a sample computation of typical pr...

  17. Heterogeneous Transmutation Sodium Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    S. E. Bays

    2007-09-01

    The threshold-fission (fertile) nature of Am-241 is used to destroy this minor actinide by capitalizing upon neutron capture instead of fission within a sodium fast reactor. This neutron-capture and its subsequent decay chain leads to the breeding of even neutron number plutonium isotopes. A slightly moderated target design is proposed for breeding plutonium in an axial blanket located above the active “fast reactor” driver fuel region. A parametric study on the core height and fuel pin diameter-to-pitch ratio is used to explore the reactor and fuel cycle aspects of this design. This study resulted in both non-flattened and flattened core geometries. Both of these designs demonstrated a high capacity for removing americium from the fuel cycle. A reactivity coefficient analysis revealed that this heterogeneous design will have comparable safety aspects to a homogeneous reactor of comparable size. A mass balance analysis revealed that the heterogeneous design may reduce the number of fast reactors needed to close the current once-through light water reactor fuel cycle.

  18. Water shielding nuclear reactor container

    International Nuclear Information System (INIS)

    The reactor container of the present invention contains a reactor pressure vessel, and has double steel plate walls endurable to elevated inner pressure and keeping airtightness, and shielding water is filled inside from a water injection port. It is endurable to a great inner pressure satisfactorily and keep airtightness by the two spaced relatively thin steel plates. It exhibits radiation shielding effect by filling water substantially the same as that of a conventional reactor container made of iron reinforced concretes. Then, it is no more necessary to use concretes for the construction of the reactor container, which shortens the term of the construction, and saves the construction cost. In addition, a cooling effect for the reactor container is provided. Syphons are disposed contiguously to a water injection port and the top end of the syphon is immersed in an equipment temporarily storage pool, and further, pipelines are connected to the double steel plate walls or the syphons for supplying shielding water to enhance the cooling effect. (N.H.)

  19. Moving ring reactor 'Karin-1'

    International Nuclear Information System (INIS)

    The conceptual design of a moving ring reactor ''Karin-1'' has been carried out to advance fusion system design, to clarify the research and development problems, and to decide their priority. In order to attain these objectives, a D-T reactor with tritium breeding blanket is designed, a commercial reactor with net power output of 500 MWe is designed, the compatibility of plasma physics with fusion engineering is demonstrated, and some other guideline is indicated. A moving ring reactor is composed mainly of three parts. In the first formation section, a plasma ring is formed and heated up to ignition temperature. The plasma ring of compact torus is transported from the formation section through the next burning section to generate fusion power. Then the plasma ring moves into the last recovery section, and the energy and particles of the plasma ring are recovered. The outline of a moving ring reactor ''Karin-1'' is described. As a candidate material for the first wall, SiC was adopted to reduce the MHD effect and to minimize the interaction with neutrons and charged particles. The thin metal lining was applied to the SiC surface to solve the problem of the compatibility with lithium blanket. Plasma physics, the engineering aspect and the items of research and development are described. (Kako, I.)

  20. Economic analysis of nuclear reactors

    International Nuclear Information System (INIS)

    The report presents several methods for estimating the power costs of nuclear reactors. When based on a consistent set of economic assumptions, total power costs may be useful in comparing reactor alternatives. The principal items contributing to the total power costs of a nuclear power plant are: (1) capital costs, (2) fuel cycle costs, (3) operation and maintenance costs, and (4) income taxes and fixed charges. There is a large variation in capital costs and fuel expenses among different reactor types. For example, the standard once-through LWR has relatively low capital costs; however, the fuel costs may be very high if U3O8 is expensive. In contrast, the FBR has relatively high capital costs but low fuel expenses. Thus, the distribution of expenses varies significantly between these two reactors. In order to compare power costs, expenses and revenues associated with each reactor may be spread over the lifetime of the plant. A single annual cost, often called a levelized cost, may be obtained by the methods described. Levelized power costs may then be used as a basis for economic comparisons. The paper discusses each of the power cost components. An exact expression for total levelized power costs is derived. Approximate techniques of estimating power costs will be presented