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1

Hewlett and Duncan - Atomic Shield | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Duncan - Atomic Shield Duncan - Atomic Shield Hewlett and Duncan - Atomic Shield Hewlett, Richard G. and Francis Duncan. Atomic Shield, 1947-1952. U.S. Atomic Energy Comission, 1972. The second volume of the three volume A History of the United States Atomic Energy Commission. Text in each PDF is fully searchable. "Hewlett and Duncan - Atomic Shield (complete).pdf" contains the complete text and images from Atomic Shield. 12mb "Hewlett and Duncan - Atomic Shield (figures only).pdf" contains hi-res (600dpi) scans of the images from Atomic Shield. 30mb Hewlett and Duncan - Atomic Shield (complete).pdf Hewlett and Duncan - Atomic Shield (figures only).pdf More Documents & Publications A History of the Atomic Energy Commission Hewlett and Duncan, Nuclear Navy, 1946-1962

2

Early shielding research at Bettis Atomic Power Laboratory  

SciTech Connect

Reminiscences of shielding research at Bettis Atomic Power Laboratory (BAPL) always have in the background the reason for its existence - the design of efficient and safe reactors. Shielding is essential for personnel safety. However, the only computational tools available in the early 1950s were slide rules and desk calculators. Under these conditions, any shield desing calculation accurate within a factor of 2 was a good one, and the phrases close enough for shielding purposes' and including a factor for conservation' became a permanent part of the shielding vocabulary. This early work instilled a respect for hand calculations and the requirements that nay result, no matter how calculated, must meet the test of being reasonable and in line with previous experience. Even today, with sophisticated shielding programs available on the latest computers, calculated results must pass the same test.

Shure, K.; Wallace, O.J. (Westinghouse Electric Corp., West Mifflin, PA (United States))

1992-01-01T23:59:59.000Z

3

Duncan - Rickover and the Nuclear Navy | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Operational Management » History » Historical Resources » Operational Management » History » Historical Resources » History Publications » Duncan - Rickover and the Nuclear Navy Duncan - Rickover and the Nuclear Navy Francis Duncan. Rickcover and the Nuclear Navy: The Discipline of Technology. 1989. The text in each PDF is fully searchable. DuncanRickoverandtheNuclearNavyComplete.pdf DuncanRickoverandtheNuclearNavyPicturesOnly.pdf More Documents & Publications Hewlett and Duncan, Nuclear Navy, 1946-1962 2008_Transition_Program_Details_Book_Three.pdf Hewlett and Holl - Atoms for Peace and War Aviation Management Green Leases Executive Secretariat Energy Reduction at HQ Real Estate Approvals Documents and Publications Facilities and Infrastructure Federal Advisory Committee Management Freedom of Information Act

4

Prediction of effective atomic number (Z) for laminated shielding material  

E-Print Network (OSTI)

, buildup factors were calculated for different mean free paths (mfp) for point isotropic sources emitting 0.5, 1, and 3 Mev photons. Some calculations were performed for double layered shields and some for three layers using spherical geometry. For two...

Sarder, Md. Maksudur Rahaman

2012-06-07T23:59:59.000Z

5

Hewlett and Duncan, Nuclear Navy, 1946-1962 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Duncan, Nuclear Navy, 1946-1962 Duncan, Nuclear Navy, 1946-1962 Hewlett and Duncan, Nuclear Navy, 1946-1962 Richard G. Hewlett and Francis Duncan. Nuclear Navy: 1946-1962. Chicago: University of Chicago Press, 1974. 477 pp. History Office publication. Traces growth of U.S. Navy's nuclear fleet from earliest beginnings to 1962 when twenty-seven submarines and three surface ships were in operation. Focuses on Admiral Hyman G. Rickover as the driving force who convinced the Navy and the Atomic Energy Commission to support the project and who then shepherded it to success. HewlettandDuncanNuclearNavyComplete.pdf HewlettandDuncanNuclearNavyFiguresOnly.pdf More Documents & Publications Duncan - Rickover and the Nuclear Navy 2008_Transition_Program_Details_Book_Three.pdf Hewlett and Anderson - New World

6

The Honorable Arne Duncan  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

7, 2011 7, 2011 The Honorable Arne Duncan Secretary of Education Washington, DC 20206-5120 Dear Secretary: As the Latino population continues to grow in the United States, so does the need to educate this growing portion of the population. Executive Order 13555, Improving Educational Opportunities and Outcomes for Latino Students, states, "only 13 percent of Latinos hold a bachelor's degree, and just 4 percent have completed graduate or professional degree programs." These are statistics we cannot ignore. In order for our Nation to maintain its global competitive edge in science and technology research and innovation support for science, technology, engineering and mathematics (STEM) education must increase, especially among Latino populations. The executive order also

7

DUNCAN PRITCHARD Reforming Reformed Epistemology*  

E-Print Network (OSTI)

DUNCAN PRITCHARD Reforming Reformed Epistemology* 0. Introduction There has been a renaissance-called "reformed" defence of the rationality of reli- gious belief. The starting-point for this reformed conception concern here. Instead, I will be outlining one way in which the reformed epistemological stance can

Edinburgh, University of

8

Charles Duncan Sworn in as Secretary of Energy | National Nuclear...  

National Nuclear Security Administration (NNSA)

Duncan Sworn in as Secretary of Energy | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation...

9

Hewlett and Holl - Atoms for Peace and War | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Operational Management » History » Historical Resources » Operational Management » History » Historical Resources » History Publications » Hewlett and Holl - Atoms for Peace and War Hewlett and Holl - Atoms for Peace and War Richard G. Hewlett and Jack M. Holl. Atoms for Peace and War: The Eisenhower Administration and the Atomic Energy Commission. A History of the Atomic Energy Commission, Volume III. Text in each PDF is fully searchable. HewlettandHollAtomsforPeaceandWarComplete.pdf HewlettandHollAtomsforPeaceandWarPicturesOnly.pdf More Documents & Publications A History of the Atomic Energy Commission Hewlett and Duncan - Atomic Shield The History of Nuclear Energy Aviation Management Green Leases Executive Secretariat Energy Reduction at HQ Real Estate Approvals Documents and Publications Facilities and Infrastructure

10

Secretaries Chu and Duncan, NSTA Announce New Energy Education Initiative  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Duncan, NSTA Announce New Energy Education Duncan, NSTA Announce New Energy Education Initiative to Promote Energy Awareness and Efficiency Secretaries Chu and Duncan, NSTA Announce New Energy Education Initiative to Promote Energy Awareness and Efficiency May 24, 2011 - 12:00am Addthis Washington, DC - U.S. Department of Energy Secretary Steven Chu joined with U.S. Department of Education Secretary Arne Duncan and Dr. Francis Eberle, Executive Director of the National Science Teachers Association (NSTA), today to announce the launch of a new energy education initiative: America's Home Energy Education Challenge. This initiative is working to educate America's youth about the benefits of energy efficiency, motivate students to play an active role in how their families use energy, and help families across the country save money. The program will encourage

11

City of Duncan, Oklahoma (Utility Company) | Open Energy Information  

Open Energy Info (EERE)

Duncan, Oklahoma (Utility Company) Duncan, Oklahoma (Utility Company) Jump to: navigation, search Name City of Duncan Place Oklahoma Utility Id 5429 Utility Location Yes Ownership M NERC Location SPP NERC SPP Yes Activity Generation Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png General Service Secondary Commercial Limited Usage General Service Secondary Commercial Power and Light Secondary Industrial Residential Service Secondary Residential Security Lighting- (1000W MH Directional Flood Lighting on existing DPUA utility Pole) Lighting Security Lighting- (1000W MH Directional Flood Lighting on existing 50 ft.

12

A Made Place, An Eternal Place: Robert Duncan's Poetics of Space  

E-Print Network (OSTI)

This dissertation examines the poetry of Robert Duncan and the dominant role space plays in that poetry. By examining the foundations of Duncan's poetics, particularly his anarchist political views, how those views pertain ...

Clothier, Matthew Allen

2010-04-27T23:59:59.000Z

13

Use of a CO{sub 2} pellet non-destructive cleaning system to decontaminate radiological waste and equipment in shielded hot cells at the Bettis Atomic Power Laboratory  

SciTech Connect

This paper details how the Bettis Atomic Power Laboratory modified and utilized a commercially available, solid carbon dioxide (CO{sub 2}) pellet, non-destructive cleaning system to support the disposition and disposal of radioactive waste from shielded hot cells. Some waste materials and equipment accumulated in the shielded hot cells cannot be disposed directly because they are contaminated with transuranic materials (elements with atomic numbers greater than that of uranium) above waste disposal site regulatory limits. A commercially available CO{sub 2} pellet non-destructive cleaning system was extensively modified for remote operation inside a shielded hot cell to remove the transuranic contaminants from the waste and equipment without generating any secondary waste in the process. The removed transuranic contaminants are simultaneously captured, consolidated, and retained for later disposal at a transuranic waste facility.

Bench, T.R.

1997-05-01T23:59:59.000Z

14

MHK Projects/Duncan Point Project | Open Energy Information  

Open Energy Info (EERE)

Duncan Point Project Duncan Point Project < MHK Projects Jump to: navigation, search << Return to the MHK database homepage Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":5,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"500px","height":"350px","centre":false,"title":"","label":"","icon":"File:Aquamarine-marker.png","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":30.3743,"lon":-91.2403,"alt":0,"address":"","icon":"http:\/\/prod-http-80-800498448.us-east-1.elb.amazonaws.com\/w\/images\/7\/74\/Aquamarine-marker.png","group":"","inlineLabel":"","visitedicon":""}]}

15

Thermocouple shield  

DOE Patents (OSTI)

A thermocouple shield for use in radio frequency fields. In some embodiments the shield includes an electrically conductive tube that houses a standard thermocouple having a thermocouple junction. The electrically conductive tube protects the thermocouple from damage by an RF (including microwave) field and mitigates erroneous temperature readings due to the microwave or RF field. The thermocouple may be surrounded by a ceramic sheath to further protect the thermocouple. The ceramic sheath is generally formed from a material that is transparent to the wavelength of the microwave or RF energy. The microwave transparency property precludes heating of the ceramic sheath due to microwave coupling, which could affect the accuracy of temperature measurements. The ceramic sheath material is typically an electrically insulating material. The electrically insulative properties of the ceramic sheath help avert electrical arcing, which could damage the thermocouple junction. The electrically conductive tube is generally disposed around the thermocouple junction and disposed around at least a portion of the ceramic sheath. The concepts of the thermocouple shield may be incorporated into an integrated shielded thermocouple assembly.

Ripley, Edward B. (Knoxville, TN)

2009-11-24T23:59:59.000Z

16

1. Slim Haddad Universit de Montral slim.haddad@umontreal.ca 2. Duncan Pedersen McGill University/ Douglas Hospital duncan.pedersen@mcgill.ca  

E-Print Network (OSTI)

1. Slim Haddad Université de Montréal slim.haddad@umontreal.ca 2. Duncan Pedersen McGill University/ Douglas Hospital duncan.pedersen@mcgill.ca 3. Marc Lucotte UQAM lucotte.marc_michel@uqam.ca 4. Pierre Fournier Université de Montréal pierre.fournier@umontreal.ca 5. Eric Dewailly Université Laval eric.Dewailly@crchul.ulaval.ca

Barthelat, Francois

17

Secretaries Chu and Duncan to Host Press Conference Call to Announce  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Duncan to Host Press Conference Call to Duncan to Host Press Conference Call to Announce National School Energy Challenge Secretaries Chu and Duncan to Host Press Conference Call to Announce National School Energy Challenge May 24, 2011 - 12:00am Addthis Washington, D.C. - On Tuesday, May 24, U.S. Energy Secretary Steven Chu and U.S. Education Secretary Arne Duncan will join with the National Science Teachers Association (NSTA) to make an announcement about a new energy education initiative to encourage students, teachers and families to learn more about energy consumption and efficiency, while inspiring students to pursue studies in science, technology, engineering and mathematics. WHO: Secretary of Energy Steven Chu Secretary of Education Arne Duncan Dr. Francis Q. Eberle, Executive Director, NSTA

18

Duncan Valley Elec Coop, Inc | Open Energy Information  

Open Energy Info (EERE)

Jump to: navigation, search Jump to: navigation, search Name Duncan Valley Elec Coop, Inc Place Arizona Utility Id 5438 Utility Location Yes Ownership C NERC Location WECC NERC WECC Yes ISO Other Yes Activity Distribution Yes Activity Bundled Services Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png Schedule LS - Private Area Lighting Service(100 and 175 watt mercury and sodium vapor) Lighting Schedule LS - Private Area Lighting Service with pole(100 and 175 watt mercury and sodium vapor) Lighting Schedule PSHL - Public Street & Highway Lighting - 100W Lamp Lighting Schedule PSHL - Public Street & Highway Lighting - 175W Lamp Lighting

19

Shielding vacuum fluctuations with graphene  

E-Print Network (OSTI)

The Casimir-Polder interaction of ground-state and excited atoms with graphene is investigated with the aim to establish whether graphene systems can be used as a shield for vacuum fluctuations of an underlying substrate. We calculate the zero-temperature Casimir-Polder potential from the reflection coefficients of graphene within the framework of the Dirac model. For both doped and undoped graphene we show limits at which graphene could be used effectively as a shield. Additional results are given for AB-stacked bilayer graphene.

Sofia Ribeiro; Stefan Scheel

2014-03-14T23:59:59.000Z

20

Magnetic shielding  

DOE Patents (OSTI)

A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines. 3 figs.

Kerns, J.A.; Stone, R.R.; Fabyan, J.

1987-10-06T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Magnetic shielding  

DOE Patents (OSTI)

A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

Kerns, John A. (Livermore, CA); Stone, Roger R. (Walnut Creek, CA); Fabyan, Joseph (Livermore, CA)

1987-01-01T23:59:59.000Z

22

Magnetic shielding  

DOE Patents (OSTI)

A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

Kerns, J.A.; Stone, R.R.; Fabyan, J.

1985-02-12T23:59:59.000Z

23

Early test facilities and analytic methods for radiation shielding: Proceedings  

SciTech Connect

This report represents a compilation of eight papers presented at the 1992 American Nuclear Society/European Nuclear Society International Meeting. The meeting is of special significance since it commemorates the fiftieth anniversary of the first controlled nuclear chain reaction. The papers contained in this report were presented in a special session organized by the Radiation Protection and Shielding Division in keeping with the historical theme of the meeting. The paper titles are good indicators of their content and are: (1) The origin of radiation shielding research: The Oak Ridge experience, (2) Shielding research at the hanford site, (3) Aircraft shielding experiments at General Dynamics Fort Worth, 1950-1962, (4) Where have the neutrons gone , a history of the tower shielding facility, (5) History and evolution of buildup factors, (6) Early shielding research at Bettis atomic power laboratory, (7) UK reactor shielding: then and now, (8) A very personal view of the development of radiation shielding theory.

Ingersoll, D.T. (comp.) (Oak Ridge National Lab., TN (United States)); Ingersoll, J.K. (comp.) (Tec-Com, Knoxville, TN (United States))

1992-11-01T23:59:59.000Z

24

Lattice Boltzmann method on irregular meshes Gongwen Peng, Haowen Xi, Comer Duncan  

E-Print Network (OSTI)

Lattice Boltzmann method on irregular meshes Gongwen Peng, Haowen Xi, Comer Duncan Department for the lattice Boltzmann method (FVLBM) is described. The scheme uses a finite­volume formulation based the lattice Boltzmann method (LBM) has been demonstrated to be an effective simulation method for fluid flow

Chou, So-Hsiang

25

Of stones, men and angels: The competing myth of Isabelle Duncan's Pre-Adamite Man (1860)  

Science Journals Connector (OSTI)

Published within weeks of Charles Darwin's Origin of Species, Isabelle Duncan's Pre-Adamite Man (1860) is the first full-length treatment of preadamism by an evangelical. Intended as a reconciliation of Genesis and geology, Duncan's work gained immediacy when it was published shortly after the September 1859 revelations that men had walked among the mammoths. Written in the tradition of evangelical Christian philosophy, Pre-Adamite Man deploys innovative biblical hermeneutics and recent trends in geology to set out both a biblical preadamite theory, and an unorthodox angelology. Duncan responded to contemporary secular interpretations of geology by pushing evangelical concordist strategies to new frontiers, filling out an acceptance of an ancient earth with new biblically informed catastrophist proposals and extensions of salvation history, while simultaneously retaining a firm commitment to plenary inspiration. The product is a highly readable book that operates both as an accessible treatment of geology and a theological discourse. Running through six printings between 1860 and 1866, the book was reviewed by many of the period's leading journals and created a minor controversy among evangelicals. This study both brings to life this previously neglected episode in scriptural geology, and adds to recent work on Victorian popular science writing.

Stephen David Snobelen

2001-01-01T23:59:59.000Z

26

CSR SHIELDING EXPERIMENT  

NLE Websites -- All DOE Office Websites (Extended Search)

of CSR shielding is described in many papers * But experimentally... Hmmm not much RF Gun 2 x 3m S-band Linac Chicane HES CTR IR Spectrometer Experimental Layout Photocathode...

27

Shielded cells transfer automation  

SciTech Connect

Nuclear waste from shielded cells is removed, packaged, and transferred manually in many nuclear facilities. Radiation exposure is absorbed by operators during these operations and limited only through procedural controls. Technological advances in automation using robotics have allowed a production waste removal operation to be automated to reduce radiation exposure. The robotic system bags waste containers out of glove box and transfers them to a shielded container. Operators control the system outside the system work area via television cameras. 9 figures.

Fisher, J J

1984-01-01T23:59:59.000Z

28

Reintroduction of Lower Columbia River Chum Salmon into Duncan Creek, 2007 Annual Report.  

SciTech Connect

The National Marine Fisheries Service (NMFS) listed Lower Columbia River (LCR) chum salmon as threatened under the Endangered Species Act (ESA) in March, 1999 (64 FR 14508, March 25, 1999). The listing was in response to the reduction in abundance from historical levels of more than one-half million returning adults to fewer than 10,000 present-day spawners. Harvest, habitat degradation, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for this decline. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of this species. This is especially true of the population located directly below Bonneville Dam, where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. Prior to 1997, only two chum salmon populations were recognized as genetically distinct in the Columbia River, although spawning had been documented in many Lower Columbia River tributaries. The first population was in the Grays River (RKm 34), a tributary of the Columbia River, and the second was a group of spawners utilizing the mainstem Columbia River just below Bonneville Dam (RKm 235) adjacent to Ives Island and in Hardy and Hamilton creeks. Using additional DNA samples, Small et al. (2006) grouped chum salmon spawning in the mainstem Columbia River and the Washington State tributaries into three groups: the Coastal, the Cascade and the Gorge. The Coastal group comprises those spawning in the Grays River, Skamokawa Creek and the broodstock used at the Sea Resources facility on the Chinook River. The Cascade group comprises those spawning in the Cowlitz (both summer and fall stocks), Kalama, Lewis, and East Fork Lewis rivers, with most supporting unique populations. The Gorge group comprises those spawning in the mainstem Columbia River from the I-205 Bridge up to Bonneville Dam and those spawning in Hamilton and Hardy creeks. Response to the federal ESA listing has been primarily through direct-recovery actions: reducing harvest, hatchery supplementation using local broodstock for populations at catastrophic risk, habitat restoration (including construction of spawning channels) and flow agreements to protect spawning and rearing areas. Both state and federal agencies have built controlled spawning areas. In 1998, the Washington Department of Fish and Wildlife (WDFW) began a chum salmon supplementation program using native stock on the Grays River. This program was expanded during 1999 - 2001 to include reintroduction into the Chinook River using eggs from the Grays River Supplementation Program. These eggs are incubated at the Grays River Hatchery, reared to release size at the Sea Resources Hatchery on the Chinook River, and the fry are released at the mouth of the Chinook River. Native steelhead, chum, and coho salmon are present in Duncan Creek, and are recognized as subpopulations of the Lower Gorge population, and are focal species in the Lower Columbia Fish Recovery Board (LCFRB) plan. Steelhead, chum and coho salmon that spawn in Duncan Creek are listed as Threatened under the ESA. Duncan Creek is classified by the LCFRB plan as a watershed for intensive monitoring (LCFRB 2004). This project was identified in the 2004 Federal Columbia River Power System (FCRPS) revised Biological Opinion (revised BiOp) to increase survival of chum salmon, 'BPA will continue to fund the program to re-introduce Columbia River chum salmon into Duncan Creek as long as NOAA Fisheries determines it to be an essential and effective contribution to reducing the risk of extinction for this ESU'. (USACE et al. 2004, page 85-86). The Governors Forum on Monitoring and Salmon Recovery and Watershed Health recommends one major population from each ESU have adult and juvenile monitoring. Duncan Creek chum salmon are identified in this plan to be intensively monitored. Planners recommended that a combination of natural and hatchery production

Hillson, Todd D. [Washington Department of Fish and Wildlife

2009-06-12T23:59:59.000Z

29

Composition for radiation shielding  

DOE Patents (OSTI)

A composition for use as a radiation shield. The shield has a depleted urum core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container.

Kronberg, James W. (Aiken, SC)

1994-01-01T23:59:59.000Z

30

Lightweight blast shield  

DOE Patents (OSTI)

A tandem warhead missile arrangement that has a composite material housing structure with a first warhead mounted at one end and a second warhead mounted near another end of the composite structure with a dome shaped composite material blast shield mounted between the warheads to protect the second warhead from the blast of the first warhead.

Mixon, Larry C. (Madison, AL); Snyder, George W. (Huntsville, AL); Hill, Scott D. (Toney, AL); Johnson, Gregory L. (Decatur, AL); Wlodarski, J. Frank (Huntsville, AL); von Spakovsky, Alexis P. (Huntsville, AL); Emerson, John D. (Arab, AL); Cole, James M. (Huntsville, AL); Tipton, John P. (Huntsville, AL)

1991-01-01T23:59:59.000Z

31

TO: Northwest Energy Efficiency Taskforce (NEET) Executive Committee FROM: Teri Duncan, Work Group 4 Co-Chair  

E-Print Network (OSTI)

1 of 1 MEMO TO: Northwest Energy Efficiency Taskforce (NEET) Executive Committee FROM: Teri Duncan by enhancing local energy efficiency initiatives and motivating consumers to adopt more energy efficient. That effort would include additional research to develop targeted messaging that motivates energy efficiency

32

Optical links for cryogenic focal-plane array readout Alan R. Johnston, Duncan TH. Liu, Siamak Forouhar,  

E-Print Network (OSTI)

Optical links for cryogenic focal-plane array readout Alan R. Johnston, Duncan TH. Liu, Siamak cryogenic focaiplane arrays must minimize power dissipation on the focal.plane. Since cooler power efficiency is low at cryogenic temperatures, reduction of focal-plane power has strong leverage in re. ducing

Fossum, Eric R.

33

Symposium on the Nature of Science—Douglas K. Duncan  

NLE Websites -- All DOE Office Websites (Extended Search)

WHAT IS SCIENCE? WHAT IS SCIENCE? The Shocking difference between what scientists think, and what students think—and what to do about it. Douglas K. Duncan Watch the talk (Running time 1:05:46) Video in Frame Detached Video Some users have reported problems with the "Video in Frame" option. If you have problems, please try the "Detached Video" option. Requires RealPlayer 7.0 or higher. Get RealPlayer What is the nature of science, and how should we teach it? How do students' views of science compare to those of scientists and science teachers? For the last several years I've been teaching large numbers of first-year college students in the "Common Core" at the University of Chicago. During the first and last week of the course I systematically collect data about

34

Composition for radiation shielding  

DOE Patents (OSTI)

A composition for use as a radiation shield is disclosed. The shield has a depleted uranium core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container. 2 figs.

Kronberg, J.W.

1994-08-02T23:59:59.000Z

35

Gas shielding apparatus  

DOE Patents (OSTI)

An apparatus for preventing oxidation by uniformly distributing inert shielding gas over the weld area of workpieces such as pipes being welded together. The apparatus comprises a chamber and a gas introduction element. The chamber has an annular top wall, an annular bottom wall, an inner side wall and an outer side wall connecting the top and bottom walls. One side wall is a screen and the other has a portion defining an orifice. The gas introduction element has a portion which encloses the orifice and can be one or more pipes. The gas introduction element is in fluid communication with the chamber and introduces inert shielding gas into the chamber. The inert gas leaves the chamber through the screen side wall and is dispersed evenly over the weld area.

Brandt, D.

1984-06-05T23:59:59.000Z

36

Actively driven thermal radiation shield  

DOE Patents (OSTI)

A thermal radiation shield for cooled portable gamma-ray spectrometers. The thermal radiation shield is located intermediate the vacuum enclosure and detector enclosure, is actively driven, and is useful in reducing the heat load to mechanical cooler and additionally extends the lifetime of the mechanical cooler. The thermal shield is electrically-powered and is particularly useful for portable solid-state gamma-ray detectors or spectrometers that dramatically reduces the cooling power requirements. For example, the operating shield at 260K (40K below room temperature) will decrease the thermal radiation load to the detector by 50%, which makes possible portable battery operation for a mechanically cooled Ge spectrometer.

Madden, Norman W. (Livermore, CA); Cork, Christopher P. (Pleasant Hill, CA); Becker, John A. (Alameda, CA); Knapp, David A. (Livermore, CA)

2002-01-01T23:59:59.000Z

37

The University of Aberdeen is a charity registered in Scotland, No SC013683 The Sir Duncan Rice Library  

E-Print Network (OSTI)

respect the facilities and please do not put feet on chairs, tables etc Alternative facilities (www.abdn.ac.uk/library/facilities/rooms-and-spaces alternative types of study and work spaces are available in The Sir Duncan Rice Library: Room/Space Floor Rice Library - Silent Study Rooms (SW corner) Laurence Bebbington, July 2013 QG GEN020 [https://www.abdn.ac.uk/library

Levi, Ran

38

The University of Aberdeen is a charity registered in Scotland, No SC013683 The Sir Duncan Rice Library  

E-Print Network (OSTI)

respect the facilities and please do not put feet on chairs, tables etc Alternative facilities (www.abdn.ac.uk/library/facilities/rooms-and-spaces alternative types of study and work spaces are available in The Sir Duncan Rice Library: Room/Space Floor Rice Library - Silent Study Rooms (SE corner) Laurence Bebbington, July 2013 QG GEN021 [https://www.abdn.ac.uk/library

Levi, Ran

39

shields-98.pdf  

NLE Websites -- All DOE Office Websites (Extended Search)

7 7 The Whole Sky Imager - A Year of Progress J. E. Shields and M. E. Karr Marine Physical Laboratory Scripps Institution of Oceanography University of California, San Diego San Diego, California T. P. Tooman Sandia National Laboratories Livermore, California D. H. Sowle and S. T. Moore Mission Research Corporation Santa Barbara, California Abstract Much progress has been made this last year in realizing the potential of the whole sky imager (WSI). Two imagers are deployed [at the Southern Great Plains (SGP) site and the Surface Heat Budget of the Arctic Ocean (SHEBA)], two are being prepared for deployment in the Tropical Western Pacific (TWP), and more are in production. Data products now include daytime thick cloud fraction and calibrated radiance. Night cloud fraction and daytime thin cloud

40

Shield Volcano | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Shield Volcano Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Shield Volcano Dictionary.png Shield Volcano: A dome shaped volcano with gently sloping sides and a broad base characteristic of relatively low viscosity, basaltic lava eruptions. Other definitions:Wikipedia Reegle Topographic Features List of topographic features commonly encountered in geothermal resource areas: Mountainous Horst and Graben Shield Volcano Flat Lava Dome Stratovolcano Cinder Cone Caldera Depression Resurgent Dome Complex Schematic representation of the internal structure of a typical shield

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Portable convertible blast effects shield  

DOE Patents (OSTI)

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler,; Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

2010-10-26T23:59:59.000Z

42

Portable convertible blast effects shield  

DOE Patents (OSTI)

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A. (Livermore, CA)

2011-03-15T23:59:59.000Z

43

Welding shield for coupling heaters  

DOE Patents (OSTI)

Systems for coupling end portions of two elongated heater portions and methods of using such systems to treat a subsurface formation are described herein. A system may include a holding system configured to hold end portions of the two elongated heater portions so that the end portions are abutted together or located near each other; a shield for enclosing the end portions, and one or more inert gas inlets configured to provide at least one inert gas to flush the system with inert gas during welding of the end portions. The shield may be configured to inhibit oxidation during welding that joins the end portions together. The shield may include a hinged door that, when closed, is configured to at least partially isolate the interior of the shield from the atmosphere. The hinged door, when open, is configured to allow access to the interior of the shield.

Menotti, James Louis (Dickinson, TX)

2010-03-09T23:59:59.000Z

44

Thermal neutron shield and method of manufacture  

DOE Patents (OSTI)

A thermal neutron shield comprising boron shielding panels with a high percentage of the element Boron. The panel is least 46% Boron by weight which maximizes the effectiveness of the shielding against thermal neutrons. The accompanying method discloses the manufacture of boron shielding panels which includes enriching the pre-cursor mixture with varying grit sizes of Boron Carbide.

Metzger, Bert Clayton; Brindza, Paul Daniel

2014-03-04T23:59:59.000Z

45

Atlas SCT/Pixel Grounding and Shielding ATLAS SCT/Pixel Grounding and Shielding Note  

E-Print Network (OSTI)

Atlas SCT/Pixel Grounding and Shielding 1 ATLAS SCT/Pixel Grounding and Shielding Note November 22 mostly connects existing mechanical electrical conductive #12; Atlas SCT/Pixel Grounding and Shielding 2 that equivalent. The barrel outer heat shield (150 aluminum) main element shield. #12; Atlas SCT/Pixel Grounding

California at Santa Cruz, University of

46

Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2002-2003 Annual Report.  

SciTech Connect

The National Marine Fisheries Service (NMFS) listed Lower Columbia River chum as threatened under the auspices of the Endangered Species Act (ESA) in March of 1999 (64 FR 14508, March 25, 1999). The listing was in response to reduction in abundance from historical levels of more than half a million returning adults to fewer than 10,000 present day spawners. Harvest, loss of habitat, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for the decline of Columbia River chum salmon. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of this species. This is especially true of the population located directly below Bonneville Dam where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. Currently, only two main populations are recognized as genetically distinct in the Columbia River, although spawning has been documented in most lower Columbia River tributaries. The first is located in the Grays River (RKm 34) (Grays population), a tributary of the Columbia, and the second is a group of spawners that utilize the Columbia River just below Bonneville Dam (RKm 235) adjacent to Ives Island and in Hardy and Hamilton creeks (Lower Gorge population). A possible third population of mainstem spawners, found in the fall of 1999, were located spawning above the I-205 bridge (approximately RKm 182), this aggregation is referred to as the Woods Landing/Rivershore population or the I-205 group. The recovery strategy for Lower Columbia River (LCR) chum as outlined in Hatchery Genetic Management Plans (HGMP) has three main tasks. First, determine if remnant populations of LCR chum salmon exist in LCR tributaries. Second, if such populations exist, develop stock-specific recovery plans involving habitat restoration including the creation of spawning refugias, supplementation if necessary and a habitat and fish monitoring and evaluation plan. If chum have been extirpated from previously utilized streams, develop re-introduction plans that utilize appropriate genetic donor stock(s) of LCR chum salmon and integrate habitat improvement and fry-to-adult survival evaluations. Third, reduce extinction risks to the Grays River chum salmon population by randomly capturing adults in the basin for use in a supplementation program and reintroduction into the Chinook River basin. The Duncan Creek project was developed using the same recovery strategy implemented for LCR chum. Biologists with the WDFW and Pacific States Marine Fisheries Commission (PSMFC) identified Duncan Creek as an ideal upriver location below Bonneville Dam for chum re-introduction. It has several attributes that make it a viable location for a re-introduction project: historically chum salmon were present, the creek is low gradient, has numerous springs/seeps, has a low potential for future development and is located close to a donor population of Lower Gorge chum. The Duncan Creek project has two goals: (1) re-introduction of chum into Duncan Creek by providing off channel high-quality spawning and incubation areas, and (2) to simultaneously evaluate natural recolonization and a supplementation strategy where adults are collected and spawned artificially at a hatchery. For supplementation, eggs are incubated and the fry reared at the Washougal Hatchery to be released back into Duncan Creek. The tasks associated with re-establishing a naturally self-sustaining population include: (1) removing mud, sand and organics present in four of the creek branches and replace with gravels expected to provide maximum egg-to-fry survival rates to a depth of at least two feet; (2) armoring the sides of these channels to reduce importation of sediment by fish spawning on the margins; (3) planting native vegetation adjacent to the channels to stabilize the banks, trap silt and provide shade; (4) annual sampling of gravel in the spawning channels to detect cha

Hillson, Todd D. (Washington Department of Fish and Wildlife, Olympia, WA)

2003-10-15T23:59:59.000Z

47

Radiation Shielding Materials and Containers Incorporating Same  

DOE Patents (OSTI)

An improved radiation shielding material and storage systems for radioactive materials incorporating the same. The PYRolytic Uranium Compound (''PYRUC'') shielding material is preferably formed by heat and/or pressure treatment of a precursor material comprising microspheres of a uranium compound, such as uranium dioxide or uranium carbide, and a suitable binder. The PYRUC shielding material provides improved radiation shielding, thermal characteristic, cost and ease of use in comparison with other shielding materials. The shielding material can be used to form containment systems, container vessels, shielding structures, and containment storage areas, all of which can be used to house radioactive waste. The preferred shielding system is in the form of a container for storage, transportation, and disposal of radioactive waste. In addition, improved methods for preparing uranium dioxide and uranium carbide microspheres for use in the radiation shielding materials are also provided.

Mirsky, Steven M.; Krill, Stephen J.; and Murray, Alexander P.

2005-11-01T23:59:59.000Z

48

Shielding and grounding in large detectors  

SciTech Connect

Prevention of electromagnetic interference (EMI), or ``noise pickup,`` is an important design aspect in large detectors in accelerator environments. Shielding effectiveness as a function of shield thickness and conductivity vs the type and frequency of the interference field is described. Noise induced in transmission lines by ground loop driven currents in the shield is evaluated and the importance of low shield resistance is emphasized. Some measures for prevention of ground loops and isolation of detector-readout systems are discussed.

Radeka, V.

1998-09-01T23:59:59.000Z

49

Biological Diversity of the Guiana Shield: Georeferencing Plants of the Guiana Shield  

E-Print Network (OSTI)

of Suriname, maximum elevation 500 m] #12;Georeferencing Plants of the Guiana Shield Google Earth allows

Mathis, Wayne N.

50

DUCRETE Shielding: A Cost Effective Alternative Radiation Shield  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary Submitted to Spectrum 2000, Sept 24-28, 2000, Chattanooga, TN Summary Submitted to Spectrum 2000, Sept 24-28, 2000, Chattanooga, TN DUCRETE: A Cost Effective Radiation Shielding Material W. J. Quapp, Starmet CMI W. H. Miller, University of Missouri-Columbia James Taylor, Starmet CMI Colin Hundley, Starmet CMI Nancy Levoy, Starmet Corporation 1. INTRODUCTION A consequence of uranium enrichment in the US has been the accumulation of nearly 740,000 metric tons of depleted uranium hexafluoride (UF 6 ) tails. 1 While this material was once considered a feed stock for the United States Breeder Reactor Program, it is no longer needed. Alternative uses of depleted uranium are few. Some have been used for medical isotope transport casks, some for industrial radioactive source shields, some for military anti-tank

51

Modified shielding jet model for twin-jet shielding analysis  

E-Print Network (OSTI)

the slowing of the jet flow due to turbulent mixing and entrainment of particles from the surrounding medium. The empirical formulations and velocity profiles derived for the respective regions of the jet consider this increase in entrained fluid... velocity profiles are integrated over their respective cross sections of the shielding jet to determine the total volumetric flowrate at the specified locations. A slug flow velocity approximation is then determined for each of the desired downstream...

Gilbride, Jennifer Frances

2012-06-07T23:59:59.000Z

52

Light shield for solar concentrators  

DOE Patents (OSTI)

A solar receiver unit including a housing defining a recess, a cell assembly received in the recess, the cell assembly including a solar cell, and a light shield received in the recess and including a body and at least two tabs, the body defining a window therein, the tabs extending outward from the body and being engaged with the recess, wherein the window is aligned with the solar cell.

Plesniak, Adam P.; Martins, Guy L.

2014-08-26T23:59:59.000Z

53

Shielding effectiveness against electromagnetic interference  

SciTech Connect

The use of metal-filled and metal-coated plastics and other modified dielectric materials to replace metals for enclosures has created a need to test these materials for their electromagnetic interference (EMI) shielding effectiveness (SE). Shielding effectiveness involves a variety of electromagnetic environments, and useful data can be obtained from tests that carefully limit the environment to that of a plane wave. Such an environment can be created in a circular or rectangular transmission line. Two such transmission line test fixtures, which hold samples of the material to be tested, have been developed. The fixtures described in this report are the National Bureau of Standards (NBS) coaxial transverse electromagnetic (TEM) cell, and a dual TEM cell constructed at ORNL from a design suggested by the NBS. The NBS coaxial fixture is an improved version of the device recommended by the American Society for Testing and Materials (ASTM). The problems associated with measuring SE are well described in the literature. The two methods described here are the result of years of work to establish procedures and instrumentation that will produce acceptable data.

Googe, J.M.; Hess, R.A.

1987-10-01T23:59:59.000Z

54

Decontaminating lead bricks and shielding  

SciTech Connect

Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially of planned decommissioning operations. Thus lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for contaminated lead is removing the superficial layer of contamination with an abrasive medium under pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a scaled-off area. The slurry of abrasive and particles of lead falls through a floor and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling.

Lussiez, G.

1994-02-01T23:59:59.000Z

55

Decontaminating lead bricks and shielding  

SciTech Connect

Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially because of planned decommissioning operations. This lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for decontaminating lead is removing the thin superficial layer of contamination with an abrasive medium trader pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a sealed-off area. The slurry of abrasive and particles of lead falls through a floor grating and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of contaminated lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling.

Lussiez, G.W.

1993-05-01T23:59:59.000Z

56

Decontaminating lead bricks and shielding  

SciTech Connect

Lead used for shielding is often surface contaminated with radioisotopes and is therefore a RCRA D008 mixed waste. The technology-based standard for treatment is macroencapsulation. However, decontaminating and recycling the clean lead is a more attractive solution. Los Alamos National Laboratory decontaminates material and equipment contaminated with radioisotopes. Decontaminating lead poses special problems because of the RCRA hazard classification and the size of the inventory, now about 50 tons and likely to grow substantially because of planned decommissioning operations. This lead, in the form of bricks and other shield shapes, is surface contaminated with fission products. One of the best methods for decontaminating lead is removing the thin superficial layer of contamination with an abrasive medium trader pressure. For lead, a mixture of alumina with water and air at about 40 psig rapidly and effectively decontaminates the lead. The abrasive medium is sprayed onto the lead in a sealed-off area. The slurry of abrasive and particles of lead falls through a floor grating and is collected in a sump. A pump sends the slurry mixture back to the spray gun, creating a continuous process. The process generates small volumes of contaminated lead slurry that can be solidified and, because it passes the TCLP, is not a mixed waste. The decontaminated lead can be released for recycling.

Lussiez, G.W.

1993-01-01T23:59:59.000Z

57

Relative radiant heat absorption characteristics of two types of mirror shields and a polished aluminum shield  

E-Print Network (OSTI)

RELATIVE RADIANT HEAT ABSORPTION CHARACTERISTICS OF TWO TYPES OF MIRROR SHIELDS AND A POLISHED ALUMINUM SHIELD A Thesis by STEVEN DOUGLAS HERRON Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE August 1973 Major Subject: Industrial Hygiene RELATIVE RADIANT HEAT ABSORPTION CHARACTERISTICS OF TWO TYPES OF MIRROR SHIELDS AND A POLISHED ALUMINUM SHIELD A Thesis by STEVEN DOUGLAS HERRON Approved...

Herron, Steven Douglas

2012-06-07T23:59:59.000Z

58

SHLDUTIL: A Code for Useful Shielding Data  

E-Print Network (OSTI)

SHLDUTIL: A Code for Useful Shielding Data by J. Kenneth Shultis and Richard E. Faw (jks 66506 SHLDUTIL is a collection of modules that yield much useful data for use in shielding analyses program. Much of the data and the details of how calculations are done can be found in one or the other

Shultis, J. Kenneth

59

Page not found | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

91 - 15800 of 29,416 results. 91 - 15800 of 29,416 results. Download Inspection Report: INS-O-00-02 Inspection of Alleged Improprieties Regarding Issuance of a Contract http://energy.gov/ig/downloads/inspection-report-ins-o-00-02 Download Hewlett and Duncan- Atomic Shield Hewlett, Richard G. and Francis Duncan. Atomic Shield, 1947-1952. U.S. Atomic Energy Comission, 1972. The second volume of the three volume A History of the United States Atomic Energy Commission.... http://energy.gov/management/downloads/hewlett-and-duncan-atomic-shield Download DOE Transmission Capacity Report http://energy.gov/oe/downloads/doe-transmission-capacity-report Download AMO Software Tools This presentation, hosted by the Advanced Manufacturing Office, provides an overview of tools and resources available for industrial energy management

60

Seismic Crystals And Earthquake Shield Application  

E-Print Network (OSTI)

We theoretically demonstrate that earthquake shield made of seismic crystal can damp down surface waves, which are the most destructive type for constructions. In the paper, seismic crystal is introduced in aspect of band gaps (Stop band) and some design concepts for earthquake and tsunami shielding were discussed in theoretical manner. We observed in our FDTD based 2D elastic wave simulations that proposed earthquake shield could provide about 0.5 reductions in magnitude of surface wave on the Richter scale. This reduction rate in magnitude can considerably reduce destructions in the case of earthquake.

B. Baykant Alagoz; Serkan Alagoz

2009-02-09T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Electromagnetic interference shielding using continuous carbon-fiber carbon-matrix and polymer-matrix composites  

E-Print Network (OSTI)

Electromagnetic interference shielding using continuous carbon-fiber carbon-matrix and polymer electromagnetic interference (EMI) shielding material with shielding effectiveness 124 dB, low surface impedance interference shielding 1. Introduction Electromagnetic interference (EMI) shielding is receiv- ing increasing

Chung, Deborah D.L.

62

Atlas SCT/Pixel Grounding and Shielding Note 1 ATLAS SCT/Pixel Grounding and Shielding Note  

E-Print Network (OSTI)

Atlas SCT/Pixel Grounding and Shielding Note 1 ATLAS SCT/Pixel Grounding and Shielding Note for SCT. This proposal mostly connects existing mechanical and electrical conductive #12;Atlas SCT. The barrel outer heat shield (150 µm aluminum) is the main element of the shield. #12;Atlas SCT

California at Santa Cruz, University of

63

Advancements in FBR shielding - Ten years in Japan  

SciTech Connect

Research and development in the area of fast breeder reactor (FBR) shielding in Japan was fully under way in April 1987 when criticality of the JOYO experimental FBR was first attained. The main activities performed and results obtained during more than 10 yr of FBR shielding research are presented. The paper describes shielding research in Joyo; Monju shielding design and related research; research activities for future FBRs; and evaluation of Monju shielding designs.

Ohtani, Nobuo; Suzuki, Soju

1990-01-01T23:59:59.000Z

64

Nuclear Navy United States Atomic Energy Commission Historical Advisory  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Navy Navy United States Atomic Energy Commission Historical Advisory Committee Chairman, Alfred D. Chandler, Jr. Harvard University John T. Conway Consolidated Edison Company Lauchlin M. Currie Carmel, California A. Hunter Dupree Brown University Ernest R. May Harvard University Robert P. Multhauf Smithsonian Institution Nuclear Navy 1946-1962 Richard G. Hewlett and Francis Duncan The University of Chicago Press Chicago and London The University of Chicago Press Chicago 60637 The University of Chicago Press Ltd., London Published 1974 Printed in the United States of America International Standard Book Number: 0-226-33219-5 Library of Congress Catalog Card Number: 74-5726 RICHARD G. HEWLETT is chief historian of the U. S. Atomic Energy Commission. He is coauthor, with Oscar E.

65

Test program element II blanket and shield thermal-hydraulic and thermomechanical testing, experimental facility survey  

SciTech Connect

This report presents results of a survey conducted by EG and G Idaho to determine facilities available to conduct thermal-hydraulic and thermomechanical testing for the Department of Energy Office of Fusion Energy First Wall/Blanket/Shield Engineering Test Program. In response to EG and G queries, twelve organizations (in addition to EG and G and General Atomic) expressed interest in providing experimental facilities. A variety of methods of supplying heat is available.

Ware, A.G.; Longhurst, G.R.

1981-12-01T23:59:59.000Z

66

Thermophysical Properties of Heat Resistant Shielding Material  

SciTech Connect

This project was aimed at determining thermal conductivity, specific heat and thermal expansion of a heat resistant shielding material for neutron absorption applications. These data are critical in predicting the structural integrity of the shielding under thermal cycling and mechanical load. The measurements of thermal conductivity and specific heat were conducted in air at five different temperatures (-31 F, 73.4 F, 140 F, 212 F and 302 F). The transient plane source (TPS) method was used in the tests. Thermal expansion tests were conducted using push rod dilatometry over the continuous range from -40 F (-40 C) to 302 F (150 C).

Porter, W.D.

2004-12-15T23:59:59.000Z

67

Experimental Test of Self-Shielding in VUV Photodissociation...  

NLE Websites -- All DOE Office Websites (Extended Search)

Experimental Test of Self-Shielding in VUV Photodissociation of CO Experimental Test of Self-Shielding in VUV Photodissociation of CO Print Wednesday, 25 March 2009 00:00 One way...

68

Summary of Prometheus Radiation Shielding Nuclear Design Analysis  

SciTech Connect

This report transmits a summary of radiation shielding nuclear design studies performed to support the Prometheus project. Together, the enclosures and references associated with this document describe NRPCT (KAPL & Bettis) shielding nuclear design analyses done for the project.

J. Stephens

2006-01-13T23:59:59.000Z

69

February, 2010 Fire Analysis of the Shielded Container  

E-Print Network (OSTI)

significant radiation (mostly gamma radiation) can be packaged within the lead shielded containers and the surface dose rate is reduced to levels for safe handling as a CH container. The shielded container, appropriate damage ratios and release estimate factors are derived for postulated fires involving the shielded

70

Thermoforming plastic in lead shield construction  

SciTech Connect

Radiation treatments using low energy X-rays or electrons frequently require a final field defining shield to be placed on the patient's skin. A custom made lead cut-out is used to provide a close fit to a particular patient's surface contours. We have developed a procedure which utilizes POLYFORM thermoplastic to obtain a negative mold of the patient instead of the traditional plaster bandage or dental impression gel. The Polyform is softened in warm water, molded carefully over the patient's surface, and is removed when set or hardened, usually within five minutes. Then lead sheet cut-outs can be formed within this negative. For shielding cut-outs requiring thicker lead sheet, a positive is made from dental stone using this Polyform negative. We have found this procedure to be neat, fast and comfortable for both patient and the dosimetrist.

Abrahams, M.E.; Chow, C.H.; Loyd, M.D. (Univ. of Texas Medical Branch, Galveston (USA))

1989-09-01T23:59:59.000Z

71

Shielding analyses: the rabbit vs the turtle?  

SciTech Connect

This paper compares solutions using Monte Carlo and discrete- ordinates methods applied to two actual shielding situations in order to make some general observations concerning the efficiency and advantages/disadvantages of the two approaches. The discrete- ordinates solutions are performed using two-dimensional geometries, while the Monte Carlo approaches utilize three-dimensional geometries with both multigroup and point cross-section data.

Broadhead, B.L.

1996-12-31T23:59:59.000Z

72

Diffusive shielding stabilizes bulk nanobubble clusters  

E-Print Network (OSTI)

Using molecular dynamics, we study the nucleation and stability of bulk nanobubble clusters. We study the formation, growth, and final size of bulk nanobubbles. We find that, as long as the bubble-bubble interspacing is small enough, bulk nanobubbles are stable against dissolution. Simple diffusion calculations provide an excellent match with the simulation results, giving insight into the reason for the stability: nanobubbles in a cluster of bulk nanobubbles "protect" each other from diffusion by a shielding effect.

Weijs, Joost H; Lohse, D

2011-01-01T23:59:59.000Z

73

On vapor shielding of dust grains of iron, molybdenum, and tungsten in fusion plasmas  

SciTech Connect

The shielding effects of ablation cloud around a small dust grain composed of iron, molybdenum, or tungsten in fusion plasmas are considered. These include collisional dissipation of momentum flux of impinging plasma ions, heat transfer by secondary plasma created due to electron impact ionization of the ablated atoms, and radiative plasma power losses in the ablation cloud. The maximum radius, which limits applicability of existing dust-plasma interaction models neglecting the cloud shielding effects, for dust grains of the considered high-Z metals is calculated as function of plasma parameters. The thermal bifurcation triggered by thermionic electron emission from dust grains, observed for some of the considered materials, is analyzed. The results are compared with previous calculations for dust composed of low-Z fusion related materials, i.e., lithium, beryllium, and carbon.

Brown, B. T.; Smirnov, R. D., E-mail: rsmirnov@ucsd.edu; Krasheninnikov, S. I. [Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0411 (United States)] [Department of Mechanical and Aerospace Engineering, University of California, San Diego, 9500 Gilman Dr., La Jolla, California 92093-0411 (United States)

2014-02-15T23:59:59.000Z

74

GRAVITATIONAL FIELD SHIELDING AND SUPERNOVA EXPLOSIONS  

SciTech Connect

A new mechanism for supernova explosions called gravitational field shielding is proposed, in accord with a five-dimensional fully covariant Kaluza-Klein theory with a scalar field that unifies the four-dimensional Einsteinian general relativity and Maxwellian electromagnetic theory. It is shown that a dense compact collapsing core of a star will suddenly turn off or completely shield its gravitational field when the core collapses to a critical density, which is inversely proportional to the square of mass of the core. As the core suddenly turns off its gravity, the extremely large pressure immediately stops the core collapse and pushes the mantle material of supernova moving outward. The work done by the pressure in the expansion can be the order of energy released in a supernova explosion. The gravity will resume and stop the core from a further expansion when the core density becomes less than the critical density. Therefore, the gravitational field shielding leads a supernova to impulsively explode and form a compact object such as a neutron star as a remnant. It works such that a compressed spring will shoot the oscillator out when the compressed force is suddenly removed.

Zhang, T. X. [Physics Department, Alabama A and M University, Normal, AL 35762 (United States)

2010-12-20T23:59:59.000Z

75

Hadronic Atoms  

E-Print Network (OSTI)

We review the theory of hadronic atoms in QCD+QED. The non-relativistic effective Lagrangian approach, used to describe this type of bound states, is illustrated with the case of pi+pi- atoms. In addition, we discuss the evaluation of isospin-breaking corrections to hadronic atom observables by invoking chiral perturbation theory.

J. Gasser; V. E. Lyubovitskij; A. Rusetsky

2009-03-02T23:59:59.000Z

76

Longwall shield design: is bigger better?  

SciTech Connect

This article evaluates the bigger is better design philosophy for longwall shields. The conventional support design approach based on simplistic models of supporting the full dead weight detached rock masses is replaced by a ground reaction design approach. Here, the goal is to match the support characteristics to the ground response, and not to try and overpower the ground forces with some massive support capability. The ground reaction concept embodies both the force and displacement controlled loading aspects, and therefore provides a more accurate representation of the support loading requirements. 7 figs.

Barczak, T.M.; Tadolini, S.C. [NIOSH-PRL, Pittsburgh, PA (United States)

2008-05-15T23:59:59.000Z

77

Shielded serpentine traveling wave tube deflection structure  

DOE Patents (OSTI)

A shielded serpentine slow wave deflection structure (10) having a serpene signal conductor (12) within a channel groove (46). The channel groove (46) is formed by a serpentine channel (20) in a trough plate (18) and a ground plane (14). The serpentine signal conductor (12) is supported at its ends by coaxial feed through connectors 28. A beam interaction trough (22) intersects the channel groove (46) to form a plurality of beam interaction regions (56) wherein an electron beam (54) may be deflected relative to the serpentine signal conductor (12).

Hudson, Charles L. (Santa Barbara, CA); Spector, Jerome (Berkeley, CA)

1994-01-01T23:59:59.000Z

78

X-ray transmissive debris shield  

DOE Patents (OSTI)

An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

Spielman, R.B.

1996-05-21T23:59:59.000Z

79

X-ray transmissive debris shield  

DOE Patents (OSTI)

An X-ray debris shield for use in X-ray lithography that is comprised of an X-ray window having a layer of low density foam exhibits increased longevity without a substantial increase in exposure time. The low density foam layer serves to absorb the debris emitted from the X-ray source and attenuate the shock to the window so as to reduce the chance of breakage. Because the foam is low density, the X-rays are hardly attenuated by the foam and thus the exposure time is not substantially increased.

Spielman, Rick B. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

80

Electromagnetic Interference (EMI) Shielding of Single-Walled Carbon  

E-Print Network (OSTI)

Electromagnetic Interference (EMI) Shielding of Single-Walled Carbon Nanotube Epoxy Composites Ning (SWNT)-polymer composites have been fabricated to evaluate the electromagnetic interference (EMI

Gao, Hongjun

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Graphene shield enhanced photocathodes and methods for making the same  

SciTech Connect

Disclosed are graphene shield enhanced photocathodes, such as high QE photocathodes. In certain embodiments, a monolayer graphene shield membrane ruggedizes a high quantum efficiency photoemission electron source by protecting a photosensitive film of the photocathode, extending operational lifetime and simplifying its integration in practical electron sources. In certain embodiments of the disclosed graphene shield enhanced photocathodes, the graphene serves as a transparent shield that does not inhibit photon or electron transmission but isolates the photosensitive film of the photocathode from reactive gas species, preventing contamination and yielding longer lifetime.

Moody, Nathan Andrew

2014-09-02T23:59:59.000Z

82

MicroShield/ISOCS gamma modeling comparison.  

SciTech Connect

Quantitative radiological analysis attempts to determine the quantity of activity or concentration of specific radionuclide(s) in a sample. Based upon the certified standards that are used to calibrate gamma spectral detectors, geometric similarities between sample shape and the calibration standards determine if the analysis results developed are qualitative or quantitative. A sample analyzed that does not mimic a calibrated sample geometry must be reported as a non-standard geometry and thus the results are considered qualitative and not quantitative. MicroShieldR or ISOCSR calibration software can be used to model non-standard geometric sample shapes in an effort to obtain a quantitative analytical result. MicroShieldR and Canberra's ISOCSR software contain several geometry templates that can provide accurate quantitative modeling for a variety of sample configurations. Included in the software are computational algorithms that are used to develop and calculate energy efficiency values for the modeled sample geometry which can then be used with conventional analysis methodology to calculate the result. The response of the analytical method and the sensitivity of the mechanical and electronic equipment to the radionuclide of interest must be calibrated, or standardized, using a calibrated radiological source that contains a known and certified amount of activity.

Sansone, Kenneth R

2013-08-01T23:59:59.000Z

83

SHIELDING ANALYSIS FOR PORTABLE GAUGING COMBINATION SOURCES  

SciTech Connect

Radioisotopic decay has been used as a source of photons and neutrons for industrial gauging operations since the late 1950s. Early portable moisture/density gauging equipment used Americium (Am)-241/Beryllium (Be)/Cesium (Cs)-137 combination sources to supply the required nuclear energy for gauging. Combination sources typically contained 0.040 Ci of Am-241 and 0.010 Ci of CS-137 in the same source capsule. Most of these sources were manufactured approximately 30 years ago. Collection, transportation, and storage of these sources once removed from their original device represent a shielding problem with distinct gamma and neutron components. The Off-Site Source Recovery (OSR) Project is planning to use a multi-function drum (MFD) for the collection, shipping, and storage of AmBe sources, as well as the eventual waste package for disposal. The MFD is an approved TRU waste container design for DOE TRU waste known as the 12 inch Pipe Component Overpack. As the name indicates, this drum is based on a 12 inch ID stainless steel weldment approximately 25 inch in internal length. The existing drum design allows for addition of shielding within the pipe component up to the 110 kg maximum pay load weight. The 12 inch pipe component is packaged inside a 55-gallon drum, with the balance of the interior space filled with fiberboard dunnage. This packaging geometry is similar to the design of a DOT 6M, Type B shipping container.

J. TOMPKINS; L. LEONARD; ET AL

2000-08-01T23:59:59.000Z

84

System for imaging plutonium through heavy shielding  

SciTech Connect

A single pinhole can be used to image strong self-luminescent gamma-ray sources such as plutonium on gamma scintillation (Anger) cameras. However, if the source is weak or heavily shielded, a poor signal to noise ratio can prevent acquisition of the image. An imaging system designed and built at Los Alamos National Laboratory uses a coded aperture to image heavily shielded sources. The paper summarizes the mathematical techniques, based on the Fast Delta Hadamard transform, used to decode raw images. Practical design considerations such as the phase of the uniformly redundant aperture and the encoded image sampling are discussed. The imaging system consists of a custom designed m-sequence coded aperture, a Picker International Corporation gamma scintillation camera, a LeCroy 3500 data acquisition system, and custom imaging software. The paper considers two sources - 1.5 mCi /sup 57/Co unshielded at a distance of 27 m and 220 g of bulk plutonium (11.8% /sup 240/Pu) with 0.3 cm lead, 2.5 cm steel, and 10 cm of dense plastic material at a distance of 77.5 cm. Results show that the location and geometry of a source hidden in a large sealed package can be determined without having to open the package. 6 references, 4 figures.

Kuckertz, T.H.; Cannon, T.M.; Fenimore, E.E.; Moss, C.E.; Nixon, K.V.

1984-04-01T23:59:59.000Z

85

Liquid Vortex Shielding for Fusion Energy Applications  

SciTech Connect

Swirling liquid vortices can be used in fusion chambers to protect their first walls and critical elements from the harmful conditions resulting from fusion reactions. The beam tube structures in heavy ion fusion (HIF) must be shielded from high energy particles, such as neutrons, x-rays and vaporized coolant, that will cause damage. Here an annular wall jet, or vortex tube, is proposed for shielding and is generated by injecting liquid tangent to the inner surface of the tube both azimuthally and axially. Its effectiveness is closely related to the vortex tube flow properties. 3-D particle image velocimetry (PIV) is being conducted to precisely characterize its turbulent structure. The concept of annular vortex flow can be extended to a larger scale to serve as a liquid blanket for other inertial fusion and even magnetic fusion systems. For this purpose a periodic arrangement of injection and suction holes around the chamber circumference are used, generating the layer. Because it is important to match the index of refraction of the fluid with the tube material for optical measurement like PIV, a low viscosity mineral oil was identified and used that can also be employed to do scaled experiments of molten salts at high temperature.

Bardet, Philippe M. [University of California, Berkeley (United States); Supiot, Boris F. [University of California, Berkeley (United States); Peterson, Per F. [University of California, Berkeley (United States); Savas, Oemer [University of California, Berkeley (United States)

2005-05-15T23:59:59.000Z

86

Semiclassical atom  

Science Journals Connector (OSTI)

Semiclassical quantization is incorporated into the average potential approach to atomic physics. The stationary energy functional is shown to be the sum of the Thomas-Fermi functional and a mainly oscillatory part. The latter turns out to be a small correction for sufficiently large atomic numbers, allowing perturbative treatment. Further, a detailed study of semiclassical spectra, with emphasis on energy degeneracy, is performed.

Berthold-Georg Englert and Julian Schwinger

1985-07-01T23:59:59.000Z

87

An atomic clock with $1\\times 10^{-18}$ room-temperature blackbody Stark uncertainty  

E-Print Network (OSTI)

The Stark shift due to blackbody radiation (BBR) is the key factor limiting the performance of many atomic frequency standards, with the BBR environment inside the clock apparatus being difficult to characterize at a high level of precision. Here we demonstrate an in-vacuum radiation shield that furnishes a uniform, well-characterized BBR environment for the atoms in an ytterbium optical lattice clock. Operated at room temperature, this shield enables specification of the BBR environment to a corresponding fractional clock uncertainty contribution of $5.5 \\times 10^{-19}$. Combined with uncertainty in the atomic response, the total uncertainty of the BBR Stark shift is now $1\\times10^{-18}$. Further operation of the shield at elevated temperatures enables a direct measure of the BBR shift temperature dependence and demonstrates consistency between our evaluated BBR environment and the expected atomic response.

Beloy, K; Phillips, N B; Sherman, J A; Schioppo, M; Lehman, J; Feldman, A; Hanssen, L M; Oates, C W; Ludlow, A D

2014-01-01T23:59:59.000Z

88

Roman ingots to shield particle detector  

Science Journals Connector (OSTI)

... aim is to use the detector to try to observe a theoretical atomic event called neutrinoless double-beta decay a radioactive process whereby an atomic nucleus releases two electrons and no neutrinos. ... Some believe the two to be one and the same. CUORE scientists will wait for neutrinoless double-beta decay to happen in a 750-kilogram cube of tellurium dioxide placed under 1,400 metres ...

Nicola Nosengo

2010-04-15T23:59:59.000Z

89

Simulations of Magnetic Shields for Spacecraft Simon G. Shepherd  

E-Print Network (OSTI)

Simulations of Magnetic Shields for Spacecraft Simon G. Shepherd Thayer School of Engineering Brian Need GV potentials!! Brehmsstrahlung radiation is potentially lethal #12;Magnetostatic Shields F=qv?B et al. 1997 a = 10 km KE = ?? eV Cst = 5 m I = "transistor radio battery" Note also that: B ~ I : B

Shepherd, Simon

90

Shielding Integral Benchmark Archive and Database (SINBAD)  

SciTech Connect

The Shielding Integral Benchmark Archive and Database (SINBAD) collection of benchmarks was initiated in the early 1990 s. SINBAD is an international collaboration between the Organization for Economic Cooperation and Development s Nuclear Energy Agency Data Bank (OECD/NEADB) and the Radiation Safety Information Computational Center (RSICC) at Oak Ridge National Laboratory (ORNL). SINBAD is a major attempt to compile experiments and corresponding computational models with the goal of preserving institutional knowledge and expertise that need to be handed down to future scientists. SINBAD is also a learning tool for university students and scientists who need to design experiments or gain expertise in modeling and simulation. The SINBAD database is currently divided into three categories fission, fusion, and accelerator benchmarks. Where possible, each experiment is described and analyzed using deterministic or probabilistic (Monte Carlo) radiation transport software.

Kirk, Bernadette Lugue [ORNL; Grove, Robert E [ORNL; Kodeli, I. [International Atomic Energy Agency (IAEA); Sartori, Enrico [ORNL; Gulliford, J. [OECD Nuclear Energy Agency

2011-01-01T23:59:59.000Z

91

Shielding integral benchmark archive and database (SINBAD)  

SciTech Connect

The shielding integral benchmark archive and database (SINBAD) collection of experiments descriptions was initiated in the early 1990s. SINBAD is an international collaboration between the Organization for Economic Cooperation and Development's Nuclear Energy Agency Data Bank (OECD/NEADB) and the Radiation Safety Information Computational Center (RSICC) at Oak Ridge National Laboratory (ORNL). SINBAD was designed to compile experiments and corresponding computational models with the goal of preserving institutional knowledge and expertise that need to be handed down to future scientists. SINBAD can serve as a learning tool for university students and scientists who need to design experiments or gain expertise in modeling and simulation. The SINBAD database is currently divided into three categories - fission, fusion, and accelerator experiments. Many experiments are described and analyzed using deterministic or stochastic (Monte Carlo) radiation transport software. The nuclear cross sections also play an important role as they are necessary in performing computational analysis. (authors)

Kirk, B.L.; Grove, R.E. [Radiation Safety Information Computational Center RSICC, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6171 (United States); Kodeli, I. [Josef Stefan Inst., Jamova 39, 1000 Ljubljana (Slovenia); Gulliford, J.; Sartori, E. [OECD NEA Data Bank, Bd des Iles, 92130 Issy-les-Moulineaux (France)

2011-07-01T23:59:59.000Z

92

Fan-fold shielded electrical leads  

DOE Patents (OSTI)

Disclosed are fan-folded electrical leads made from copper cladded Kapton, for example, with the copper cladding on one side serving as a ground plane and the copper cladding on the other side being etched to form the leads. The Kapton is fan folded with the leads located at the bottom of the fan-folds. Electrical connections are made by partially opening the folds of the fan and soldering, for example, the connections directly to the ground plane and/or the lead. The fan folded arrangement produces a number of advantages, such as electrically shielding the leads from the environment, is totally non-magnetic, and has a very low thermal conductivity, while being easy to fabricate. 3 figs.

Rohatgi, R.R.; Cowan, T.E.

1996-06-11T23:59:59.000Z

93

Recovery Act Workers Clear Reactor Shields from Brookhaven Lab | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Workers Clear Reactor Shields from Brookhaven Lab Workers Clear Reactor Shields from Brookhaven Lab Recovery Act Workers Clear Reactor Shields from Brookhaven Lab American Recovery and Reinvestment Act workers are in the final stage of decommissioning a nuclear reactor after they recently removed thick steel shields once used to absorb neutrons produced for research. The Brookhaven National Laboratory is using $39 million from the Recovery Act to decommission the Brookhaven Graphite Research Reactor, the world's first reactor built solely for peaceful research purposes. Recovery Act Workers Clear Reactor Shields from Brookhaven Lab More Documents & Publications Brookhaven Graphite Research Reactor Workshop 2011 ARRA Newsletters Idaho Crews Overcome Challenges to Safely Dispose 1-Million-Pound Hot Cell

94

Analytic flux formulas and tables of shielding functions  

SciTech Connect

Hand calculations of radiation flux and dose rates are often useful in evaluating radiation shielding and in determining the scope of a problem. The flux formulas appropriate to such calculations are almost always based on the point kernel and allow for at most the consideration of laminar slab shields. These formulas often require access to tables of values of integral functions for effective use. Flux formulas and function tables appropriate to calculations involving homogeneous source regions with the shapes of lines, disks, slabs, truncated cones, cylinders, and spheres are presented. Slab shields may be included in most of these calculations, and the effect of a cylindrical shield surrounding a cylindrical source may be estimated. Detector points may be located axially, laterally, or interior to a cylindrical source. Line sources may be tilted with respect to a slab shield. All function tables are given for a wide range of arguments.

Wallace, O.J.

1981-06-01T23:59:59.000Z

95

Nanocrystalline Cs{sub x}WO{sub 3} particles: Effects of N{sub 2} annealing on microstructure and near-infrared shielding characteristics  

SciTech Connect

In order to further improve the near-infrared shielding properties of cesium tungsten bronze (Cs{sub x}WO{sub 3}) for solar filter applications, Cs{sub x}WO{sub 3} particles were prepared by solvothermal reaction method and the effects of nitrogen annealing on the microstructure and near-infrared shielding properties of Cs{sub x}WO{sub 3} were investigated. The obtained Cs{sub x}WO{sub 3} samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and spectrophotometer. The results indicate that nanosheet-like Cs{sub x}WO{sub 3} particles with hexagonal structure began to transform into nanorods after annealed at temperature higher than 600 C. The near-infrared shielding properties of Cs{sub x}WO{sub 3} particles could be further improved by N{sub 2} annealing at 500700 C. Particularly, the 500 C-annealed Cs{sub x}WO{sub 3} samples in the N{sub 2} atmosphere showed best near-infrared shielding properties. It was suggested that the excellent near-infrared shielding ability of the 500 C-annealed Cs{sub x}WO{sub 3} samples is correlated with its minimum O/W atomic ratio and most oxygen vacancies. Highlights: N{sub 2} annealing could further improve the near-infrared (NIR) shielding of Cs{sub x}WO{sub 3}. Effects of N{sub 2} annealing on microstructure and NIR shielding of Cs{sub x}WO{sub 3} were studied. The 500 C-N{sub 2}-annealed Cs{sub x}WO{sub 3} exhibited minimum O/W ratio and most oxygen vacancies. The 500 C-N{sub 2}-annealed Cs{sub x}WO{sub 3} particles exhibited best NIR shielding properties.

Liu, Jing-Xiao, E-mail: drliu-shi@dlpu.edu.cn [School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034 (China); Institute of Multidisciplinary Research for Advanced Material, Tohoku University, Sendai, 980-8577,Japan (Japan); Shi, Fei; Dong, Xiao-Li; Xu, Qiang [School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034 (China); Yin, Shu; Sato, Tsugio [Institute of Multidisciplinary Research for Advanced Material, Tohoku University, Sendai, 980-8577,Japan (Japan)

2013-10-15T23:59:59.000Z

96

RELATIVE ATTENUATION CHARACTERISTICS OF SOME SHIELDING MATERIALS FOR PuB NEUTRONS  

E-Print Network (OSTI)

1: Polyethylene Water Spodumene-gypsum Gypsum, wet and dryconstituents of the spodumene-gypsum, and gypsum shields.SPODUMENK,GYPSUM SHIELD 30% Spodumene by weight 40% Gypsum

Bringham, P.S.

2010-01-01T23:59:59.000Z

97

Polyethylene as a Radiation Shielding Standard in Simulated Cosmic-Ray Environments  

E-Print Network (OSTI)

on the ISS through polyethylene shielding augmentation ofnucleon Iron-56 in Polyethylene. II. , Comparisons betweenPolyethylene as a Radiation Shielding Standard in Simulated

2006-01-01T23:59:59.000Z

98

E-Print Network 3.0 - analytical shielding calculations Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Use of Magnetic and Electrically Conductive Fillers in a Polymer Matrix for Electromagnetic Interference Shielding Summary: for Electromagnetic Interference Shielding JUNHUA WU1,2...

99

DARHT : integration of shielding design and analysis with facility design /  

SciTech Connect

The design of the interior portions of the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility incorporated shielding and controls from the beginning of the installation of the Accelerators. The purpose of the design and analysis was to demonstrate the adequacy of shielding or to determine the need for additional shielding or controls. Two classes of events were considered: (1) routine operation defined as the annual production of 10,000 2000-ns pulses of electrons at a nominal energy of 20 MeV, some of which are converted to the x-ray imaging beam consisting of four nominal 60-ns pulses over the 2000-ns time frame, and (2) accident case defined as up to 100 2000-ns pulses of electrons accidentally impinging on some metallic surface, thereby producing x rays. Several locations for both classes of events were considered inside and outside of the accelerator hall buildings. The analysis method consisted of the definition of a source term for each case studied and the definition of a model of the shielding and equipment present between the source and the dose areas. A minimal model of the fixed existing or proposed shielding and equipment structures was used for a first approximation. If the resulting dose from the first approximation was below the design goal (1 rem/yr for routine operations, 5 rem for accident cases), then no further investigations were performed. If the result of the first approximation was above our design goals, the model was refined to include existing or proposed shielding and equipment. In some cases existing shielding and equipment were adequate to meet our goals and in some cases additional shielding was added or administrative controls were imposed to protect the workers. It is expected that the radiation shielding design, exclusion area designations, and access control features, will result in low doses to personnel at the DARHT Facility.

Boudrie, R. L. (Richard L.); Brown, T. H. (Thomas H.); Gilmore, W. E. (Walter E.); Downing, J. N. (James N.), Jr.; Hack, Alan; McClure, D. A. (Donald A.); Nelson, C. A. (Christine A.); Wadlinger, E. Alan; Zumbro, M. V. (Martha V.)

2002-01-01T23:59:59.000Z

100

Shielding design for the proposed Advanced Photon Source at Argonne  

SciTech Connect

Bulk shielding was designed for the proposed Argonne Advanced Photon Source. The shielding is for two linacs, the positron converter, booster synchrotron, and the storage ring. Shielding design limits exposure to 20 mrem/wk for occupational and 25 mrem/y for an individual member of the public from the radiation products, which include high energy neutrons (HEN), giant resonance neutrons (GRN), and Bremsstrahlung radiation (BR). The beam loss parameters at various components were estimated. Dose rates were computed for continuous loss during beam decay using an empirical method. Normal operational losses and certain accidental beam losses were also considered.

Moe, H.J.; Veluri, V.R.

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Atom Interferometry  

ScienceCinema (OSTI)

Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

Mark Kasevich

2010-01-08T23:59:59.000Z

102

Electric field shielding in dielectric nanosolutions  

E-Print Network (OSTI)

To gain some insight into electrochemical activity of dielectric colloids of technical and biomedical interest we investigate a model of dielectric nanosolution whose micro-constitution is dominated by dipolarions -- positively and negatively charged spherically symmetric nano-structures composed of ionic charge surrounded by cloud of radially polarized dipoles of electrically neutral molecules of solvent. Combing the standard constitutive equations of an isotropic dielectric liquid with Maxwell equation of electrostatics and presuming the Boltzmann shape of the particle density of bound-charge we derive equation for the in-medium electrostatic field. Particular attention is given to numerical analysis of obtained analytic solutions of this equation describing the exterior fields of dipolarions with dipolar atmospheres of solvent molecules endowed with either permanent or field-induced dipole moments radially polarized by central symmetric field of counterions. The presented computations show that the electric field shielding of dipolarions in dielectric nanosolutions is quite different from that of counterionic nano-complexes of Debye-H\\"uckel theory of electrolytes.

Sergey Bastrukov; Pik-Yin Lai; Irina Molodtsova

2014-03-26T23:59:59.000Z

103

Recovery Act Workers Clear Reactor Shields from Brookhaven Lab  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

UPTON, N.Y. - American Recovery and Reinvestment Act UPTON, N.Y. - American Recovery and Reinvestment Act workers are in the final stage of decommissioning a nuclear reactor after they recently removed thick steel shields once used to absorb neutrons produced for research. The Brookhaven National Laboratory is using $39 million from the Recovery Act to decommission the Brookhaven Graphite Research Reactor, the world's first reactor built solely for peaceful research purposes. The decommissioning is slated for completion later this year and will end Office of Environmental Management legacy cleanup activities at the Lab. The neutron shields were located on the north and south sides of a 700-ton graphite pile. The three-inch-thick shields absorbed neutrons that escaped from the graphite pile. The shields also limited movement of the pile when the reactor was in opera-

104

Neutron shielding and activation of the MASTU device and surrounds  

E-Print Network (OSTI)

A significant functional upgrade is planned for the Mega Ampere Spherical Tokamak (MAST) device, located at Culham in the UK, including the implementation of a notably greater neutral beam injection power. This upgrade will cause the emission of a substantially increased intensity of neutron radiation for a substantially increased amount of time upon operation of the device. Existing shielding and activation precautions are shown to prove insufficient in some regards, and recommendations for improvements are made, including the following areas: shielding doors to MAST shielded facility enclosure (known as "the blockhouse"); north access tunnel; blockhouse roof; west cabling duct. In addition, some specific neutronic dose rate questions are addressed and answered; those discussed here relate to shielding penetrations and dose rate reflected from the air above the device ("skyshine").

Taylor, David; Turner, Andrew; Davis, Andrew

2014-01-01T23:59:59.000Z

105

Method for the construction of x-ray shielding masks  

SciTech Connect

A method is described for the production of a rigid model of a patient's face onto which lead shielding sheets may be contoured. The model is cast in Lipowitz's metal using a plaster mold.

Canup, D.; Ekstrand, K.E.

1982-03-01T23:59:59.000Z

106

A Magnetic Shielding Type Superconducting Fault-Current Limiter  

Science Journals Connector (OSTI)

In a Magnetic Shielding type Fault-Current Limiter (MSFCL), the characteristics of the magnetic ... ) is an important factor in limiting the current flow. In this study, to improve the efficiency of the fault current

N. Miyauchi; H. Nakane; S. Haseyama; S. Yoshizawa

1999-01-01T23:59:59.000Z

107

RELIGION, EPISTEMOLOGY OF Duncan Pritchard  

E-Print Network (OSTI)

Fideism Reformed Epistemology Criticism of Reformed Epistemology Religious Experience Science by the rise of reformed epistemology which has energised the debate and brought this topic into mainstream (2009) have the distinctive merit of having been written by two of the leading figures in the reformed

Edinburgh, University of

108

Effectiveness of the thyroid shield in dental radiology  

SciTech Connect

The effectiveness of the thyroid shield in reducing patient exposure during routine dental radiographic examinations was studied. A nonscreen film and two film-screen combinations were used as dosimeters and to show the spatial distribution of x-ray exposure. The error in the absolute accuracy of the film dosimeter and the error in the reproducibility of the film-screen combinations were less than +/- 10%. Measurements of thyroid exposure and exposure distribution, with and without the shield, were made on a Rando phantom and on patients. In the phantom study, the reduction by the shield of exposure to the thyroid from primary beam and from scatter was found to be highly dependent on the position of the primary beam relative to the thyroid gland but independent of kVp. Exposure reduction by the shield varied from 5% to 56% for a complete-mouth survey, 2% to 18% for a bitewing survey, and 10% to 79% for a panoramic survey. In the patient study, thyroid skin exposures measured on adults were 33% to 84% lower in offices in which the shield was used as compared to offices in which it was not used. Thyroid skin exposures measured on children were 63% to 92% lower. In accordance with the ALARA principle, these results support the routine use of the thyroid shield for all dental radiography.

Sikorski, P.A.; Taylor, K.W.

1984-08-01T23:59:59.000Z

109

Atom Probe Tomography | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

Atom Probe Tomography Atom Probe Tomography The LEAP 4000 XHR local electrode atom probe tomography instrument enabled the first-ever comprehensive and accurate 3-D chemical...

110

Hanford Waste Treatment Plant Sets Massive Protective Shield door in  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Waste Treatment Plant Sets Massive Protective Shield door Waste Treatment Plant Sets Massive Protective Shield door in Pretreatment Facility Hanford Waste Treatment Plant Sets Massive Protective Shield door in Pretreatment Facility January 12, 2011 - 12:00pm Addthis The carbon steel doors come together to form an upside-down L-shape. The 102-ton door was set on top of the 85-ton door that was installed at the end of December. The carbon steel doors come together to form an upside-down L-shape. The 102-ton door was set on top of the 85-ton door that was installed at the end of December. The 102-ton shield door measures 52 feet wide and 15 feet tall The 102-ton shield door measures 52 feet wide and 15 feet tall The carbon steel doors come together to form an upside-down L-shape. The 102-ton door was set on top of the 85-ton door that was installed at the end of December.

111

Renormalization shielding and eikonal analysis on the atomic collision in dense partially ionized hydrogen plasmas  

SciTech Connect

The renormalization plasma screening effects on the electron-ion collision are investigated in dense partially ionized hydrogen plasmas. The Hamilton-Jacobi and eikonal methods with the effective interaction potential are employed to obtain the eikonal scattering phase shift and eikonal cross section for the electron-ion collision. It is found that the influence of renormalization screening strongly suppresses the eikonal scattering phase shift as well as the eikonal cross section, especially, for small impact parameter regions. In addition, the renormalization screening effect reduces the total eikonal cross section in all energy domains. The variation of the renormalization effects on the electron-ion collision in dense partially ionized hydrogen plasmas is also discussed.

Kim, Sung Soo [Department of Applied Mathematics, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of)] [Department of Applied Mathematics, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of); Jung, Young-Dae [Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of) [Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of); Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, New York 12180-3590 (United States)

2013-12-15T23:59:59.000Z

112

Atomic magnetometer  

DOE Patents (OSTI)

An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

2012-07-03T23:59:59.000Z

113

Fault current limiter with shield and adjacent cores  

DOE Patents (OSTI)

In a fault current limiter (FCL) of a saturated core type having at least one coil wound around a high permeability material, a method of suppressing the time derivative of the fault current at the zero current point includes the following step: utilizing an electromagnetic screen or shield around the AC coil to suppress the time derivative current levels during zero current conditions.

Darmann, Francis Anthony; Moriconi, Franco; Hodge, Eoin Patrick

2013-10-22T23:59:59.000Z

114

A Toroidal Magnetic Spacecraft Shield Simon G. Shepherd  

E-Print Network (OSTI)

A Toroidal Magnetic Spacecraft Shield Simon G. Shepherd Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire, 03755 John P. G. Shepherd Department of Physics, University of Wisconsin potential angle around spacecraft cross-section a radius of coil B magnetic flux density Bin vector

Shepherd, Simon

115

NASA TM-2012-217361 Evaluating Shielding Approaches to Reduce  

E-Print Network (OSTI)

NASA TM-2012-217361 Evaluating Shielding Approaches to Reduce Space Radiation Cancer Risks Francis A. Cucinotta NASA Lyndon B. Johnson Space Center Houston, Texas Myung-Hee Y. Kim U.S.R.A., Division, Texas May 2012 #12;THE NASA STI PROGRAM OFFICE . . . IN PROFILE Since its founding, NASA has been

Rathbun, Julie A.

116

Spin-rotation and NMR shielding constants in HCl  

SciTech Connect

The spin-rotation and nuclear magnetic shielding constants are analysed for both nuclei in the HCl molecule. Nonrelativistic ab initio calculations at the CCSD(T) level of approximation show that it is essential to include relativistic effects to obtain spin-rotation constants consistent with accurate experimental data. Our best estimates for the spin-rotation constants of {sup 1}H{sup 35}Cl are C{sub Cl} = ?53.914kHz and C{sub H} = 42.672kHz (for the lowest rovibrational level). For the chlorine shielding constant, the ab initio value computed including the relativistic corrections, ?(Cl) = 976.202ppm, provides a new absolute shielding scale; for hydrogen we find ?(H) = 31.403ppm (both at 300K). Combining the theoretical results with our new gas-phase NMR experimental data allows us to improve the accuracy of the magnetic dipole moments of both chlorine isotopes. For the hydrogen shielding constant, including relativistic effects yields better agreement between experimental and computed values.

Jaszu?ski, Micha?, E-mail: michal.jaszunski@icho.edu.pl [Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warszawa, Kasprzaka 44 (Poland)] [Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warszawa, Kasprzaka 44 (Poland); Repisky, Michal; Demissie, Taye B.; Komorovsky, Stanislav; Malkin, Elena; Ruud, Kenneth [Centre for Theoretical and Computational Chemistry, University of TromsThe Arctic University of Norway, N-9037 Troms (Norway)] [Centre for Theoretical and Computational Chemistry, University of TromsThe Arctic University of Norway, N-9037 Troms (Norway); Garbacz, Piotr; Jackowski, Karol; Makulski, W?odzimierz [Laboratory of NMR Spectroscopy, Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw (Poland)] [Laboratory of NMR Spectroscopy, Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw (Poland)

2013-12-21T23:59:59.000Z

117

A Note on Hamilton Cycles in Kneser Graphs Ian Shields  

E-Print Network (OSTI)

A Note on Hamilton Cycles in Kneser Graphs Ian Shields IBM P.O. Box 12195 Research Triangle Park) have Hamilton cycles when n #20; 27. A similar result is shown for bipartite Kneser graphs. 1 for Hamilton cycles in Kneser graphs, K(n; k), and bipartite Kneser graphs, H(n; k). With the exception

Savage, Carla D.

118

Accelerator shield design of KIPT neutron source facility  

SciTech Connect

Argonne National Laboratory (ANL) of the United States and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the design development of a neutron source facility at KIPT utilizing an electron-accelerator-driven subcritical assembly. Electron beam power is 100 kW, using 100 MeV electrons. The facility is designed to perform basic and applied nuclear research, produce medical isotopes, and train young nuclear specialists. The biological shield of the accelerator building is designed to reduce the biological dose to less than 0.5-mrem/hr during operation. The main source of the biological dose is the photons and the neutrons generated by interactions of leaked electrons from the electron gun and accelerator sections with the surrounding concrete and accelerator materials. The Monte Carlo code MCNPX serves as the calculation tool for the shield design, due to its capability to transport electrons, photons, and neutrons coupled problems. The direct photon dose can be tallied by MCNPX calculation, starting with the leaked electrons. However, it is difficult to accurately tally the neutron dose directly from the leaked electrons. The neutron yield per electron from the interactions with the surrounding components is less than 0.01 neutron per electron. This causes difficulties for Monte Carlo analyses and consumes tremendous computation time for tallying with acceptable statistics the neutron dose outside the shield boundary. To avoid these difficulties, the SOURCE and TALLYX user subroutines of MCNPX were developed for the study. The generated neutrons are banked, together with all related parameters, for a subsequent MCNPX calculation to obtain the neutron and secondary photon doses. The weight windows variance reduction technique is utilized for both neutron and photon dose calculations. Two shielding materials, i.e., heavy concrete and ordinary concrete, were considered for the shield design. The main goal is to maintain the total dose outside the shield boundary at less than 0.5-mrem/hr. The shield configuration and parameters of the accelerator building have been determined and are presented in this paper. (authors)

Zhong, Z.; Gohar, Y. [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States)

2013-07-01T23:59:59.000Z

119

Near field coupling to shielded cable due to switching operation in substation  

Science Journals Connector (OSTI)

It is vital to study the electromagnetic coupling to shielded cable for improving electromagnetic antiinterference ability of secondary equipment in a substation. As a hybrid of method of moment ... shielded cabl...

Lei Qi; Xiang Cui

2008-09-01T23:59:59.000Z

120

PERGAMON Carbon 39 (2001) 279285 Electromagnetic interference shielding effectiveness of carbon  

E-Print Network (OSTI)

PERGAMON Carbon 39 (2001) 279­285 Review Electromagnetic interference shielding effectiveness materials for electromagnetic interference (EMI) shielding are reviewed. They include composite materials-structural and structural composites, colloi- dal graphite, as well as EMI gasket materials. Electromagnetic interference

Chung, Deborah D.L.

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

E-Print Network 3.0 - aircraft shield test reactor Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

shield test reactor Search Powered by Explorit Topic List Advanced Search Sample search results for: aircraft shield test reactor Page: << < 1 2 3 4 5 > >> 1 A' Brief. History of...

122

Electromagnetic interference shielding reaching 70 dB in steel fiber cement  

E-Print Network (OSTI)

Electromagnetic interference shielding reaching 70 dB in steel fiber cement Sihai Wen, D.D.L. Chung; Silica fume; Shielding 1. Introduction Electromagnetic interference (EMI) shielding [1­4] is in critical, NY 14260-4400, USA Received 9 January 2002; accepted 14 August 2003 Abstract An electromagnetic

Chung, Deborah D.L.

123

Procedures for application of Don Cossairt's CASIM calculations in TM-1140 to bulk shielding  

SciTech Connect

As part of the methodology documentation for the site-wide radiation shielding assessment, these two related notes were written showing how to apply the CASIM calculations of TM-1140 to determine required shielding for various beam intensities and steel-soil composites. These notes have been reviewed by the Fermilab ES H Section and approved for use in evaluating shielding requirements.

Garbincius, P.H.

1991-02-01T23:59:59.000Z

124

Measuring atomic properties with an atom interferometer  

E-Print Network (OSTI)

Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths, one of which travels through an interaction region. The paths ...

Roberts, Tony David, 1972-

2002-01-01T23:59:59.000Z

125

Validation of nuclear models used in space radiation shielding applications  

SciTech Connect

A program of verification and validation has been undertaken to assess the applicability of models to space radiation shielding applications and to track progress as these models are developed over time. In this work, simple validation metrics applicable to testing both model accuracy and consistency with experimental data are developed. The developed metrics treat experimental measurement uncertainty as an interval and are therefore applicable to cases in which epistemic uncertainty dominates the experimental data. To demonstrate the applicability of the metrics, nuclear physics models used by NASA for space radiation shielding applications are compared to an experimental database consisting of over 3600 experimental cross sections. A cumulative uncertainty metric is applied to the question of overall model accuracy, while a metric based on the median uncertainty is used to analyze the models from the perspective of model development by examining subsets of the model parameter space.

Norman, Ryan B., E-mail: Ryan.B.Norman@nasa.gov [NASA Langley Research Center, Hampton, VA 23681 (United States); Blattnig, Steve R. [NASA Langley Research Center, Hampton, VA 23681 (United States)] [NASA Langley Research Center, Hampton, VA 23681 (United States)

2013-01-15T23:59:59.000Z

126

Secret key distillation from shielded two-qubit states  

E-Print Network (OSTI)

The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.

Joonwoo Bae

2008-03-03T23:59:59.000Z

127

Secret key distillation from shielded two-qubit states  

SciTech Connect

The quantum states corresponding to a secret key are characterized using the so-called private states, where the key part consisting of a secret key is shielded by the additional systems. Based on the construction, it was shown that a secret key can be distilled from bound entangled states. In this work, I consider the shielded two-qubit states in a key-distillation scenario and derive the conditions under which a secret key can be distilled using the recurrence protocol or the two-way classical distillation, advantage distillation together with one-way postprocessing. From the security conditions, it is shown that a secret key can be distilled from bound entangled states in a much wider range. In addition, I consider the case that in which white noise is added to quantum states and show that the classical distillation protocol still works despite a certain amount of noise although the recurrence protocol does not.

Bae, Joonwoo [School of Computational Sciences, Korea Institute for Advanced Study, Seoul 130-722 (Korea, Republic of)

2010-05-15T23:59:59.000Z

128

The effect of electrostatic shielding using invisibility cloak  

Science Journals Connector (OSTI)

The effect of electrostatic shielding for a spherical invisibility cloak with arbitrary charges inside is investigated. Our result reveals that the charge inside the cloak is a crucial factor to determine the detection. When charged bodies are placed inside the cloak with an arbitrary distribution the electric fields outside are purely determined by the total charges just as the fields of a point charge at the center of the cloak. As the total charges reduce to zero the bodies can not be detected. On the other hand if the total charges are nonzero the electrostatic potential inside an ideal cloak tends to infinity. For unideal cloaks this embarrassment is overcome while they still have good behaviors of shielding. In addition the potential across the inner surface of an ideal cloak is discontinuous due to the infinite polarization of the dielectric however it can be alternatively interpreted as the dual Meissner effect of a dual superconductive layer with a surface magnetic current.

Ruo-Yang Zhang; Qing Zhao; Mo-Lin Ge

2011-01-01T23:59:59.000Z

129

SATIF-2 shielding aspects of accelerators, targets and irradiation facilities  

SciTech Connect

Particle accelerators have evolved over the last 50 years from simple devices to powerful machines, and will continue to have an important impact on research, technology and lifestyle. Today they cover a wide range of applications, from television and computer displays in households to the investigation of the origin and structure of matter. It has become common practice to use them for material science and medical applications. In recent years, requirements from new technological and research applications have emerged, such as increased particle beams intensities, higher flexibility, etc., giving rise to new radiation shielding aspects and problems. These proceedings review recent progress in radiation shielding of accelerator facilities, and evaluate advancements with respect to international co-operation in this field.

NONE

1995-12-31T23:59:59.000Z

130

SEU43 fuel bundle shielding analysis during spent fuel transport  

SciTech Connect

The basic task accomplished by the shielding calculations in a nuclear safety analysis consist in radiation doses calculation, in order to prevent any risks both for personnel protection and impact on the environment during the spent fuel manipulation, transport and storage. The paper investigates the effects induced by fuel bundle geometry modifications on the CANDU SEU spent fuel shielding analysis during transport. For this study, different CANDU-SEU43 fuel bundle projects, developed in INR Pitesti, have been considered. The spent fuel characteristics will be obtained by means of ORIGEN-S code. In order to estimate the corresponding radiation doses for different measuring points the Monte Carlo MORSE-SGC code will be used. Both codes are included in ORNL's SCALE 5 programs package. A comparison between the considered SEU43 fuel bundle projects will be also provided, with CANDU standard fuel bundle taken as reference. (authors)

Margeanu, C. A.; Ilie, P.; Olteanu, G. [Inst. for Nuclear Research Pitesti, No. 1 Campului Street, Mioveni 115400, Arges County (Romania)

2006-07-01T23:59:59.000Z

131

Proposal of DC shield reactor type superconducting fault current limiter  

Science Journals Connector (OSTI)

Saturated DC reactor type superconducting fault current limiter (SFCL) had been proposed two years ago. It was classified to rectifier type SFCL. The changing inductance value with the operating mode has superior characteristics to reduce voltage sag during step increase of the load current. But it has the disadvantage of its weight. In this paper, rectifier type SFCL with shielded reactor has been proposed. The reactor which has superconducting ring or tube inside its winding is substituted to the DC link of the rectifier. The configuration looks like an air core transformer with secondary short winding. When the current through the bulk shield-ring reaches to a certain level, the flux penetrates to the shield body and finite impedance appears in the primary winding. In other words, when the surface flux density exceeds its critical flux density, the flux penetrates into the bulk superconductor, and increases equivalent inductance. The equivalent transient resistance of the shield was represented as a function of exponential of the time. Using this equivalent transient resistance, the transient impedance was expressed. The transient wave analysis using EMTDC (electro-magnetic transients in DC systems) has been described. Simulated waveforms are shown considering the source inductance, the leakage inductance, the coupling coefficient and the forward voltage drop of the semiconductor. And voltage sag was also investigated with 50% step load increase. Preliminary design was also performed. The coil size and number of turns are designed to obtain adequate inductance for the current limitation, and the central magnetic field of the coils are calculated. There is optimal aspect ratio to minimize the magnetic field with restriction in outer diameter of the coil.

Itsuya Muta; Tsutomu Hoshino; Khosru Mohammad Salim; Akio Kawasaki; Taketsune Nakamura; Masato Yamada

2004-01-01T23:59:59.000Z

132

Shielding design aspects of thermionic space nuclear reactors  

SciTech Connect

It has been well documented that nuclear power sources will be required for the future exploration of space. Higher power levels (>10 kW (electric)) will be enabling, if not absolutely necessary, for the continued expansion of a human presence in the solar system and beyond. Space missions that will directly benefit continued life on Earth, including the monitoring for climate change and global warming, high-capacity communication satellites, and large, space-based radar systems to monitor the flow of airline traffic, will require progressively larger amounts of electrical power. Military applications, even with the ending of the Cold War, will continue to be needed for treaty verification activities. A thermionic energy conversion-based nuclear reactor system is one of the many different technologies proposed for the utilization of nuclear energy in space. How the energy conversion is accomplished and the equipment requiring shielding have a profound effect on the overall shielding requirements for the system. There exist two configurations of this technology that can be exploited and will have a significant effect on shielding needs. The paper discusses in-core thermionic conversion and out-of-core conversion concepts.

Klein, A.C.

1991-01-01T23:59:59.000Z

133

ACCURATE TEMPERATURE MEASUREMENTS IN A NATURALLY-ASPIRATED RADIATION SHIELD  

SciTech Connect

Experiments and calculations were conducted with a 0.13 mm fine wire thermocouple within a naturally-aspirated Gill radiation shield to assess and improve the accuracy of air temperature measurements without the use of mechanical aspiration, wind speed or radiation measurements. It was found that this thermocouple measured the air temperature with root-mean-square errors of 0.35 K within the Gill shield without correction. A linear temperature correction was evaluated based on the difference between the interior plate and thermocouple temperatures. This correction was found to be relatively insensitive to shield design and yielded an error of 0.16 K for combined day and night observations. The correction was reliable in the daytime when the wind speed usually exceeds 1 m s{sup -1} but occasionally performed poorly at night during very light winds. Inspection of the standard deviation in the thermocouple wire temperature identified these periods but did not unambiguously locate the most serious events. However, estimates of sensor accuracy during these periods is complicated by the much larger sampling volume of the mechanically-aspirated sensor compared with the naturally-aspirated sensor and the presence of significant near surface temperature gradients. The root-mean-square errors therefore are upper limits to the aspiration error since they include intrinsic sensor differences and intermittent volume sampling differences.

Kurzeja, R.

2009-09-09T23:59:59.000Z

134

Theoretical prediction of nuclear magnetic shieldings and indirect spin-spin coupling constants in 1,1-, cis-, and trans-1,2-difluoroethylenes  

SciTech Connect

A theoretical prediction of nuclear magnetic shieldings and indirect spin-spin coupling constants in 1,1-, cis- and trans-1,2-difluoroethylenes is reported. The results obtained using density functional theory (DFT) combined with large basis sets and gauge-independent atomic orbital calculations were critically compared with experiment and conventional, higher level correlated electronic structure methods. Accurate structural, vibrational, and NMR parameters of difluoroethylenes were obtained using several density functionals combined with dedicated basis sets. B3LYP/6-311++G(3df,2pd) optimized structures of difluoroethylenes closely reproduced experimental geometries and earlier reported benchmark coupled cluster results, while BLYP/6-311++G(3df,2pd) produced accurate harmonic vibrational frequencies. The most accurate vibrations were obtained using B3LYP/6-311++G(3df,2pd) with correction for anharmonicity. Becke half and half (BHandH) density functional predicted more accurate {sup 19}F isotropic shieldings and van Voorhis and Scuseria's ?-dependent gradient-corrected correlation functional yielded better carbon shieldings than B3LYP. A surprisingly good performance of Hartree-Fock (HF) method in predicting nuclear shieldings in these molecules was observed. Inclusion of zero-point vibrational correction markedly improved agreement with experiment for nuclear shieldings calculated by HF, MP2, CCSD, and CCSD(T) methods but worsened the DFT results. The threefold improvement in accuracy when predicting {sup 2}J(FF) in 1,1-difluoroethylene for BHandH density functional compared to B3LYP was observed (the deviations from experiment were ?46 vs. ?115 Hz)

Nozirov, Farhod, E-mail: teobaldk@gmail.com, E-mail: farhod.nozirov@gmail.com [Department of Physics, 4513 Manhattan College Parkway Riverdale, New York 10471 (United States)] [Department of Physics, 4513 Manhattan College Parkway Riverdale, New York 10471 (United States); Stachw, Micha?, E-mail: michal.stachow@gmail.com [Faculty of Chemistry, Opole University, 48, Oleska Street, 45-052 Opole (Poland)] [Faculty of Chemistry, Opole University, 48, Oleska Street, 45-052 Opole (Poland); Kupka, Teobald, E-mail: teobaldk@gmail.com, E-mail: farhod.nozirov@gmail.com

2014-04-14T23:59:59.000Z

135

Elements & Compounds Atoms (Elements)  

E-Print Network (OSTI)

#12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12;Nucleus Electrons Cloud of negative charge (2 electrons) Fig. 2.5: Simplified model of a Helium (He) Atom He 4.002602 2 Helium Mass Number (~atomic mass) = number of Neutrons + Protons = 4 for Helium Atomic

Frey, Terry

136

WAPDEG Analysis of Waste Package and Drip shield Degradation  

SciTech Connect

As directed by ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]), an analysis of the degradation of the engineered barrier system (EBS) drip shields and waste packages at the Yucca Mountain repository is developed. The purpose of this activity is to provide the TSPA with inputs and methodologies used to evaluate waste package and drip shield degradation as a function of exposure time under exposure conditions anticipated in the repository. This analysis provides information useful to satisfy ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]) requirements. Several features, events, and processes (FEPs) are also discussed (Section 6.2, Table 15). The previous revision of this report was prepared as a model report in accordance with AP-SIII.10Q, Models. Due to changes in the role of this report since the site recommendation, it no longer contains model development. This revision is prepared as a scientific analysis in accordance with AP-SIII.9Q, ''Scientific Analyses'' and uses models previously validated in (1) ''Stress Corrosion Cracking of the Drip Shield, the Waste Package Outer Barrier, and the Stainless Steel Structural Material'' (BSC 2004 [DIRS 169985]); (2) ''General Corrosion and Localized Corrosion of Waste Package Outer Barrier'' (BSC 2004 [DIRS 169984]); and (3) ''General Corrosion and Localized Corrosion of Drip Shield'' (BSC 2004 [DIRS 169845]). The integrated waste package degradation (IWPD) analysis presented in this report treats several implementation-related issues, such as defining the number and size of patches per waste package that undergo stress corrosion cracking; recasting the weld flaw analysis in a form as implemented in the Closure Weld Defects (CWD) software; and, general corrosion rate manipulations (e.g., change of scale in Section 6.3.4). The weld flaw portion of this report takes input from an engineering calculation (BSC 2004 [DIRS 170024]) and uses standard mathematical methods to enable easier implementation. The IWPD analysis also provides guidance on implementation of early failures (importance sampling and multinomial distribution usage). These manipulations are evident from standard scientific practices, approaches, or methods and do not require changes to the previously validated models. The IWPD analysis itself (Section 6.4), not the resultant curves from executing the IWPD analysis presented in Section 6.5 (which are for illustrative purposes), is used directly in total system performance assessment (TSPA). The IWPD analysis simulates general corrosion and stress corrosion cracking of the waste package outer barrier and general corrosion of the drip shield. The effects of igneous and seismic events and localized corrosion on drip shield and waste package performance are not evaluated in this report. The outputs of this report are inputs and methodologies used by TSPA to evaluate waste package and drip shield degradation as a function of exposure time under exposure conditions anticipated in the repository. The analyses presented in this report are for the current repository design (BSC 2004 [DIRS 168489]).

K. Mon

2004-09-29T23:59:59.000Z

137

Neutral atom traps.  

SciTech Connect

This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

Pack, Michael Vern

2008-12-01T23:59:59.000Z

138

7 -ATOMIC PROCESSES Atomic processes can be  

E-Print Network (OSTI)

1 7 - ATOMIC PROCESSES Atomic processes can be: 1. Scattering 2. Absorption/Thermal Emission scattering, although the results won't change much when this condition is relaxed. Absorption/Thermal Emission Free-free (continuum) ("Bremsstrahlung") Emission/Absorption #12;2 Bound-Bound & Bound

Sitko, Michael L.

139

7 -ATOMIC PROCESSES Atomic processes can be  

E-Print Network (OSTI)

1 7 - ATOMIC PROCESSES Atomic processes can be: 1. Scattering 2. Absorption/Thermal Emission scattering, although the results won't change much when this condition is relaxed. #12;2 Absorption/Thermal Emission Free-free (continuum) ("Bremsstrahlung") Emission/Absorption Bound-Bound & Bound-Free Processes

Sitko, Michael L.

140

Dose estimates in a loss of lead shielding truck accident.  

SciTech Connect

The radiological transportation risk & consequence program, RADTRAN, has recently added an updated loss of lead shielding (LOS) model to it most recent version, RADTRAN 6.0. The LOS model was used to determine dose estimates to first-responders during a spent nuclear fuel transportation accident. Results varied according to the following: type of accident scenario, percent of lead slump, distance to shipment, and time spent in the area. This document presents a method of creating dose estimates for first-responders using RADTRAN with potential accident scenarios. This may be of particular interest in the event of high speed accidents or fires involving cask punctures.

Dennis, Matthew L.; Osborn, Douglas M.; Weiner, Ruth F.; Heames, Terence John (Alion Science & Technology Albuquerque, NM)

2009-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

A new radiation shielding block material for radiation therapy  

SciTech Connect

In recent years, lead has been recognized as a source of environmental pollution; this includes lead use for radiation shielding in radiotherapy. We looked for a new material that could be a lead substitute. We chose a material composed of tungsten and resin. We compared the attenuation coefficient of the material with those of lead and Lipowitz's metal, and found the material has a higher attenuation coefficient than the other two. The material may be used as a substitute for lead because it is easy to fabricate and friendly to the environment.

Tajiri, Minoru; Sunaoka, Masayoshi; Fukumura, Akifumi; Endo, Masahiro [Radiological Technology Office, National Institute of Radiological Sciences 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Department of Medical Physics, National Institute of Radiological Sciences 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan)

2004-11-01T23:59:59.000Z

142

Submicron carbon filament cement-matrix composites for electromagnetic interference shielding  

SciTech Connect

Carbon filaments of diameter 0.1 mm were found to be a much more effective additive than conventional carbon fibers of diameter 10 mm in providing cement pastes capable of electromagnetic interference shielding. With 0.54 vol. % filaments and a shield thickness of 4 mm, a shielding effectiveness of 30 dB was attained at 1--2 GHz. However, the filaments were less effective than the fibers for reinforcing and for providing strain sensing cement-matrix composites.

Fu, X.; Chung, D.D.L. [State Univ. of New York, Buffalo, NY (United States). Composite Materials Research Lab.] [State Univ. of New York, Buffalo, NY (United States). Composite Materials Research Lab.

1996-10-01T23:59:59.000Z

143

New Six-Layer Magnetically-Shielded Room for MEG D. Cohen1,2  

E-Print Network (OSTI)

by Imedco, to house a 4-D MEG system, containing both gradiometers and magnetometers (Vectorview of the passive shielding factor yield 1,630 (64dB), 3,600 (71dB), 240,000 (107dB) , and 78,000,000 (158d of 0.010 to 0.10 Hz. The 78 dB was to combine 58 dB of passive shielding with 20 dB of active shielding

144

Reading Comprehension - Atomic History  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic History Atomic History A Greek philosopher named Democritus said that all atoms are small, hard particles. He thought that atoms were made of a single material formed into different shapes and sizes. The word " _________ element compound mixture atom " is derived from the Greek word "atomos" which means "not able to be divided." In 1803, John Dalton, a school teacher, proposed his atomic theory. Dalton's theory states that elements (substances composed of only one type of _________ molecules ions atom ) combine in certain proportions to form _________ compounds atoms mixtures elements . In 1897, a British scientist named J. J. Thomson experimented with a cathode-ray tube which had a positively charged plate. The plate attracted negatively charged particles that we now call _________ protons neutrons

145

The Universe Adventure - Atoms  

NLE Websites -- All DOE Office Websites (Extended Search)

Matter and Atoms Matter and Atoms Richard Feynman "If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations of creatures, what statement would contain the most information in the fewest words? I believe it is that...all things are made of atoms." -Richard P. Feynman, winner of the 1965 Nobel Prize in Physics All is atoms Matter is made of atoms, and atoms are comprised of protons, neutrons, and electrons. Everything in the Universe is made of matter. Though matter exists in many different forms, each form is made out of the same basic constituents: small particles called atoms. Atoms themselves are made of smaller particles: protons, neutrons, and electrons. Protons and neutrons are composed of even smaller particles called quarks.

146

EXPERIMENTAL EVALUATION OF THE THERMAL PERFORMANCE OF A WATER SHIELD FOR A SURFACE POWER REACTOR  

SciTech Connect

Water based reactor shielding is being investigated for use on initial lunar surface power systems. A water shield may lower overall cost (as compared to development cost for other materials) and simplify operations in the setup and handling. The thermal hydraulic performance of the shield is of significant interest. The mechanism for transferring heat through the shield is natural convection. Natural convection in a 100 kWt lunar surface reactor shield design is evaluated with 2 kW power input to the water in the Water Shield Testbed (WST) at the NASA Marshall Space Flight Center. The experimental data from the WST is used to validate a CFD model. Performance of the water shield on the lunar surface is then predicted with a CFD model anchored to test data. The experiment had a maximum water temperature of 75 C. The CFD model with 1/6-g predicts a maximum water temperature of 88 C with the same heat load and external boundary conditions. This difference in maximum temperature does not greatly affect the structural design of the shield, and demonstrates that it may be possible to use water for a lunar reactor shield.

REID, ROBERT S. [Los Alamos National Laboratory; PEARSON, J. BOSIE [Los Alamos National Laboratory; STEWART, ERIC T. [Los Alamos National Laboratory

2007-01-16T23:59:59.000Z

147

Instrumented, Shielded Test Canister System for Evaluation of Spent Nuclear Fuel in Dry Storage  

SciTech Connect

This document describes the development of an instrumented, shielded test canister system to store and monitor aluminum-based spent nuclear duel under dry storage conditions.

Sindelar, R.L.

1999-10-21T23:59:59.000Z

148

E-Print Network 3.0 - advanced shielding systems Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Computer Engineering, University of Rochester Collection: Engineering 77 Electromagnetic interference shielding using continuous carbon-fiber carbon-matrix and polymer-matrix...

149

1. Shielding against Electromagnetic Interference With telecommunication networks connecting wireless devices around the globe, there  

E-Print Network (OSTI)

#12;1. Shielding against Electromagnetic Interference With telecommunication networks connecting electromagnetic interference (EMI) across the airwaves. These communication networks are ubiquitous and dynamic

Rincon-Mora, Gabriel A.

150

Power System Feedback from High-Tc Superconductor Shielded Core Fault Current Limiter  

Science Journals Connector (OSTI)

The shielded core fault current limiter is attractive with high critical temperature superconductors. ... acts during normal operation as an ideally shorted current transformer; the secondary superconducting loop...

J. Gerhold

1998-01-01T23:59:59.000Z

151

Final analysis of the GCFR radial blanket and shield integral experiment  

SciTech Connect

An integral experiment has been performed for verification of radiation transport methods and nuclear data used in the design of the radial shield for the proposed gas-cooled fast breeder reactor demonstration plant. The experiment was conducted at the ORNL Tower Shielding Facility and consisted of integral and spectral measurements of the neutron and gamma-ray flux transmitted through slabs of materials which modeled a GCFR-type radial blanket and radial shield. Both UO/sub 2/ and ThO/sub 2/ blankets were investigated as well as several shield designs comprising stainless steel, graphite, and boronated graphite.

Ingersoll, D.T.; Williams, L.R.

1981-04-01T23:59:59.000Z

152

Atomizing nozzle and process  

DOE Patents (OSTI)

High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

1993-07-20T23:59:59.000Z

153

Atomic Energy Commission : Atomic Power at Shippingport - 1958 Educational Film  

SciTech Connect

The United States Atomic Energy Commission & Westinghouse Electric Company take us on a tour of an atomic power station.

None

2013-02-02T23:59:59.000Z

154

Simbol-X Mirror Module Thermal Shields: I - Design and X-Ray Transmission  

SciTech Connect

The Simbol-X mission is designed to fly in formation flight configuration. As a consequence, the telescope has both ends open to space, and thermal shielding at telescope entrance and exit is required to maintain temperature uniformity throughout the mirrors. Both mesh and meshless solutions are presently under study for the shields. We discuss the design and the X-ray transmission.

Collura, A.; Varisco, S. [INAF-OAPA Via G.F. Ingrassia, 31 90123 Palermo (Italy); Barbera, M. [INAF-OAPA Via G.F. Ingrassia, 31 90123 Palermo (Italy); DSFA Universita di Palermo, Via Archirafi 36, 90123 Palermo (Italy); Basso, S.; Pareschi, G.; Tagliaferri, G. [INAF-OAB, via E. bianchi 46, 23807 Merate (Italy); Ayers, T. [Luxel Corporation, Friday Harbor, WA 98250 (United States)

2009-05-11T23:59:59.000Z

155

Lunar soil as shielding against space radiation J. Miller a,*, L. Taylor b  

E-Print Network (OSTI)

Lunar soil as shielding against space radiation J. Miller a,*, L. Taylor b , C. Zeitlin c , L Sciences, Chiba 263-8555, Japan a r t i c l e i n f o Article history: Received 6 August 2008 Accepted 28 January 2009 Keywords: Lunar soil Lunar regolith Space radiation shielding Galactic cosmic radiation (GCR

Perfect, Ed

156

Combined Use of Magnetic and Electrically Conductive Fillers in a Polymer Matrix for Electromagnetic Interference Shielding  

E-Print Network (OSTI)

for Electromagnetic Interference Shielding JUNHUA WU1,2 and D.D.L. CHUNG1,3 1.--Composite Materials Research for electromagnetic interference shielding than the use of a highly magnetic filler alone or the use of a highly, magnetic, electrical resistivity, nickel, mumetal, graphite INTRODUCTION Electromagnetic interference (EMI

Chung, Deborah D.L.

157

The influence of single-walled carbon nanotube structure on the electromagnetic interference shielding  

E-Print Network (OSTI)

The influence of single-walled carbon nanotube structure on the electromagnetic interference.01­15%) have been evaluated for electromagnetic interference (EMI) shielding effectiveness (SE) in the X and aerospace sectors with uses such as electrostatic dissipation, electromagnetic interference (EMI) shielding

Gao, Hongjun

158

Shielding-Effectiveness Modeling of Carbon-Fiber/Nylon-6,6 Composites  

E-Print Network (OSTI)

Shielding-Effectiveness Modeling of Carbon-Fiber/Nylon- 6,6 Composites Nicholas B. Janda,1 Jason M for various amounts of Thermal- Graph DKD X carbon fiber within nylon 6,6. The theory predicts that the most important parameters for the shield- ing effectiveness of a sample are the carbon-fiber volume percentage

Perger, Warren F.

159

IComposite Structures -ManufacturingAdvanced Radiation Shielding Materials and Structures Technical Abstract  

E-Print Network (OSTI)

and instruments and survivability require effective radiation protection. There is also the desire to reduce several compositions that provide optimum radiation shielding. We plan to address specific NASA missionSBIR SBIR 54 55 IComposite Structures - ManufacturingAdvanced Radiation Shielding Materials

160

Turbo Pump Magnetic Shielding Analysis NSTX-CALC-24-04-00  

E-Print Network (OSTI)

NSTX Turbo Pump Magnetic Shielding Analysis NSTX-CALC-24-04-00 March 16, 2011 Prepared By turbo pump to reduce the fringe field from NSTX coils at the pump location to below 50 gauss shield is below 50 G and overall Lorentz force on the pump is below 50 pound. 3) Although the magnetic

Princeton Plasma Physics Laboratory

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Shielding requirements for K Basin waste transfer line  

SciTech Connect

K-East Basin sludge, mixed with water, is to be transported to the tank farms using a high integrity container mounted on a trailer. Load considerations preclude driving the truck directly to the tank opening. Thus, it is envisioned that a transfer line will run from a tanker unloading point to a point where the waste can be injected into a waste tank. It is presently envisioned that the waste will be pumped from the truck to the tank in a three inch pipe which is encased inside a six inch pipe. The transfer line will be shielded by either berming earth with a density of approximately 2.00 g/cm{sup 3} (125 lb/ft{sup 3}) around the line, or constructing a concrete raceway.

Goldberg, H.J.

1996-04-01T23:59:59.000Z

162

CORROSION OF LEAD SHIELDING IN NUCLEAR MATERIALS PACKAGES  

SciTech Connect

Inspection of United States-Department of Energy (US-DOE) model 9975 nuclear materials shipping package revealed corrosion of the lead shielding induced by off-gas constituents from organic components in the package. Experiments were performed to determine the corrosion rate of lead when exposed to off-gas or degradation products of these organic materials. The results showed that the room temperature vulcanizing (RTV) sealant was the most corrosive organic species followed by the polyvinyl acetate (PVAc) glue. The fiberboard material induced corrosion to a much lesser extent than the PVAc glue and RTV, and only in the presence of condensed water. The results indicated faster corrosion at temperatures higher than ambient and with condensed water as expected. A corrosion rate of 0.05 mm/year measured for coupons exposed to the most aggressive conditions was recommended as a conservative estimate for use in package performance calculations.

Subramanian, K; Kerry Dunn, K

2007-11-16T23:59:59.000Z

163

Large Magnetic Shielding Factor Measured by Nonlinear Magneto-optical Rotation  

E-Print Network (OSTI)

A passive magnetic shield was designed and constructed for magnetometer tests for the future neutron electric dipole moment experiment at TRIUMF. The axial shielding factor of the magnetic shield was measured using a magnetometer based on non-linear magneto-optical rotation of the plane of polarized laser light upon passage through a paraffin-coated vapour cell containing natural Rb at room temperature. The laser was tuned to the Rb D1 line, near the $^{85}$Rb $F=2\\rightarrow 2,3$ transition. The shielding factor was measured by applying an axial field externally and measuring the magnetic field internally using the magnetometer. The axial shielding factor was determined to be $(1.3\\pm 0.1)\\times 10^{7}$, from an applied axial field of 1.45~$\\mu$T in the background of Earth's magnetic field.

Jeffery W. Martin; Russell R. Mammei; Wolfgang Klassen; Cameron Cerasani; Taraneh Andalib; Christopher P. Bidinosti; Michael Lang; David Ostapchuk

2014-11-07T23:59:59.000Z

164

ATOMS PEACE WAR Eisenhower  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

ATOMS ATOMS PEACE WAR Eisenhower and the Atomic Energy Commission Richard G. Hewlett and lack M. Roll With a Foreword by Richard S. Kirkendall and an Essay on Sources by Roger M. Anders University of California Press Berkeley Los Angeles London Published 1989 by the University of California Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England Prepared by the Atomic Energy Commission; work made for hire. Library of Congress Cataloging-in-Publication Data Hewlett, Richard G. Atoms for peace and war, 1953-1961. (California studies in the history of science) Bibliography: p. Includes index. 1. Nuclear energy-United States-History. 2. U.S. Atomic Energy Commission-History. 3. Eisenhower, Dwight D. (Dwight David), 1890-1969.

165

Accelerated guided atomic pulse  

Science Journals Connector (OSTI)

The deleterious effects of dispersion on a propagating coherent atomic pulse, along the axis of a traveling-wave laser beam, can be ameliorated by the nonlinear self-interacting force due to dipole-dipole coupling between atoms. We show that a wide atomic pulse with a particular profile can retain its shape during propagation and, moreover, the momentum of the pulse increases due to photon absorption. For the wide soliton case, we demonstrate analytically that the self-interacting atomic force scales inversely with the third power of the pulse width.

S. Dyrting; Weiping Zhang; B. C. Sanders

1997-09-01T23:59:59.000Z

166

Atomic Collapse Observed  

NLE Websites -- All DOE Office Websites (Extended Search)

Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

167

Multiplicative Sets of Atoms.  

E-Print Network (OSTI)

??It is possible for an element to have both an atom factorization and a factorization that will always contain a reducible element. This leads us (more)

Rand, Ashley Nicole

2013-01-01T23:59:59.000Z

168

Improved graphite furnace atomizer  

DOE Patents (OSTI)

A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

Siemer, D.D.

1983-05-18T23:59:59.000Z

169

Atom Nano-Optics  

Science Journals Connector (OSTI)

Nanolocalized light fields composed of photon dots and photon holes are being used to control the motion of atoms on a nanometer spatial scale.

Balykin, Victor; Klimov, Vasilii; Letokhov, Vladilen

2005-01-01T23:59:59.000Z

170

Use of fly ash as an admixture for electromagnetic interference shielding Jingyao Cao, D.D.L. Chung*  

E-Print Network (OSTI)

Use of fly ash as an admixture for electromagnetic interference shielding Jingyao Cao, D.D.L. Chung The use of fly ash as an admixture results in enhancement of the electromagnetic interference (EMI of fly ash as an admixture for enhancing the electromagnetic interference (EMI) shielding. EMI shielding

Chung, Deborah D.L.

171

| International Atomic Energy Agency Nuclear Fusion Nucl. Fusion 54 (2014) 023004 (9pp) doi:10.1088/0029-5515/54/2/023004  

E-Print Network (OSTI)

| International Atomic Energy Agency Nuclear Fusion Nucl. Fusion 54 (2014) 023004 (9pp) doi:10 Tatyana Sizyuk and Ahmed Hassanein Center for Materials under Extreme Environment, School of Nuclear for publication 17 December 2013 Published 21 January 2014 Abstract The plasma shielding effect is a well

Harilal, S. S.

172

Lessons from shielding retrofits at the LAMPF/LANSCE/PSR accelerator, beam lines and target facilities  

SciTech Connect

The experience in the past 7 years to improve the shielding and radiation control systems at the Los Alamos Meson Physics Facility (LAMPF) and the Manuel Lujan Jr. Neutron Scattering Center (LANSCE) provides important lessons for the design of radiation control systems at future, high beam power proton accelerator facilities. Major issues confronted and insight gained in developing shielding criteria and in the use of radiation interlocks are discussed. For accelerators and beam lines requiring hands-on-maintenance, our experience suggests that shielding criteria based on accident scenarios will be more demanding than criteria based on routinely encountered beam losses. Specification and analysis of the appropriate design basis accident become all important. Mitigation by active protection systems of the consequences of potential, but severe, prompt radiation accidents has been advocated as an alternate choice to shielding retrofits for risk management at both facilities. Acceptance of active protection systems has proven elusive primarily because of the difficulty in providing convincing proof that failure of active systems (to mitigate the accident) is incredible. Results from extensive shielding assessment studies are presented including data from experimental beam spill tests, comparisons with model estimates, and evidence bearing on the limitations of line-of-sight attenuation models in complex geometries. The scope and significant characteristics of major shielding retrofit projects at the LAMPF site are illustrated by the project to improve the shielding beneath a road over a multiuse, high-intensity beam line (Line D).

Macek, R.J.

1994-07-01T23:59:59.000Z

173

Atoms for Peace Awards  

Science Journals Connector (OSTI)

... Technology, is to be chairman of the Organization and Planning Committee of Atoms for Peace Awards. In addition to Dr. Killian, the Committee will include Dr. Detlev W. ... and Dr. Alan Waterman, director of the National Science Foundation. The Atoms for Peace Awards, it will be recalled, were established last summer as a memorial to Henry Ford ...

1955-10-29T23:59:59.000Z

174

Hirshfeld atom refinement  

Science Journals Connector (OSTI)

The new automated iterative Hirshfeld atom refinement method is explained and validated through comparison of structural models of Gly-L-Ala obtained from synchrotron X-ray and neutron diffraction data at 12, 50, 150 and 295 K. Structural parameters involving hydrogen atoms are determined with comparable precision from both experiments and agree mostly to within two combined standard uncertainties.

Capelli, S.C.

2014-08-29T23:59:59.000Z

175

Atomic dark matter  

SciTech Connect

We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has interesting implications for cosmology as well as direct detection: Weak-scale dark atoms can accommodate hyperfine splittings of order 100 keV, consistent with the inelastic dark matter interpretation of the DAMA data while naturally evading direct detection bounds. Moreover, protohalo formation can be suppressed below M{sub proto} ? 10{sup 3}10{sup 6}M{sub s}un for weak scale dark matter due to Ion-Radiation and Ion-Atom interactions in the dark sector.

Kaplan, David E.; Krnjaic, Gordan Z.; Rehermann, Keith R.; Wells, Christopher M., E-mail: dkaplan@pha.jhu.edu, E-mail: gordan@pha.jhu.edu, E-mail: keith@pha.jhu.edu, E-mail: cwells13@pha.jhu.edu [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2686 (United States)

2010-05-01T23:59:59.000Z

176

Simbol-X Mirror Module Thermal Shields: II-Small Angle X-Ray Scattering Measurements  

SciTech Connect

The formation flight configuration of the Simbol-X mission implies that the X-ray mirror module will be open to Space on both ends. In order to reduce the power required to maintain the thermal stability and, therefore, the high angular resolution of the shell optics, a thin foil thermal shield will cover the mirror module. Different options are presently being studied for the foil material of these shields. We report results of an experimental investigation conducted to verify that the scattering of X-rays, by interaction with the thin foil material of the thermal shield, will not significantly affect the performances of the telescope.

Barbera, M. [Universita degli Studi di Palermo, Dip. di Scienze Fisiche ed Astronomiche, Palermo (Italy); Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Palermo G.S. Vaiana, Palermo (Italy); Ayers, T. [Luxel Corporation, Friday Harbor (WA) (United States); Collura, A. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Palermo G.S. Vaiana, Palermo (Italy); Nasillo, G. [Universita degli Studi di Palermo, Centro Grandi Apparecchiature, Palermo (Italy); Pareschi, G.; Tagliaferri, G. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Brera, Merate (Italy)

2009-05-11T23:59:59.000Z

177

The use of isotopically tailored boron for advanced neutron shielding and moderating applications  

E-Print Network (OSTI)

cm. The incident neutron flux was measured first without any shielding slab between the source and the detector. The first slab of shielding material was then placed nearest to the source and the transmitted intensity was measured by the detector... effects of nuclear radiation. This analysis examined the use of isotopically tailored boron for the purpose of moderating, reflecting and shielding neutrons. The source of neutrons in this study varied in energy from 0. 2 keV to 14 MeV. The material...

Deere, Laura Marie

2012-06-07T23:59:59.000Z

178

Increasing transcurium production efficiency through direct resonance shielding  

SciTech Connect

The Radiochemical Engineering Development Center at Oak Ridge National Laboratory is the world s leader in production of 252Cf. This and other heavy actinides are produced by irradiation of mixed curium/americium targets in the High Flux Isotope Reactor. Due to the strong dependence of isotopic cross sections upon incoming neutron energy, the efficiency with which an isotope is transmuted is highly dependent upon the neutron flux energy spectrum and intensities. There are certain energy ranges in which the rate of fissions in feedstock materials can be minimized relative to the rate of (n, ) absorptions. It is shown that by perturbing the flux spectrum, it is possible to alter the net consumption of curium feedstock, as well as the yields of key isotopes for the heavy element research program, such as 249Bk and 252Cf. This flux spectrum perturbation is accomplished by means of focused resonance shielding through the use of filter materials. It is further shown that these perturbations can alter the target yields in a significant way, increasing the amount of 252Cf produced per unit curium consumption by over 40%.

Hogle, Susan L [ORNL; Maldonado, G Ivan [ORNL; Alexander, Charles W [ORNL

2013-01-01T23:59:59.000Z

179

Distributed resonance self-shielding using the equivalence principle  

SciTech Connect

This paper presents an extension of the equivalence principle to allow distributed resonance self-shielding in a multi-region fuel configuration. Rational expansion of fuel-to-fuel collision probability is applied in order to establish equivalence between the actual fuel configuration and a homogeneous mixture of hydrogen and resonant absorber, which is a commonly used model to calculate library tables of resonance integrals. The main steps in derivation are given along with the basic physics assumptions on which the presented approach relies. The method has been implemented in the lattice code WIMS-AECL and routinely used for calculation of CANDU-type reactor lattices. Its capabilities are illustrated by comparison of WIMS-AECL and MCNP results of {sup 238}U resonance capture in a CANDU lattice cell. In order to determine optimal rational expansion of fuel-to-fuel collision probability, the calculations were carried out by varying the number of rational terms from 1 to 6. The results show that 4 terms are sufficient. The further increase of the number of terms affects the computing time, while the impact on accuracy is negligible. To illustrate the convergence of the results, the fuel subdivision is gradually refined varying the number of fuel pin subdivisions from 1 to 32 equal-area annuli. The results show very good agreement with the reference MCNP calculation. (authors)

Altiparmakov, D. [Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, ON K0J 1J0 (Canada)

2012-07-01T23:59:59.000Z

180

STATEMENT OF CONSIDERATIONS REQUEST BY RED SHIELD ACQUISITION, LLC FOR AN ADVANCE WAIVER OF  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

RED SHIELD ACQUISITION, LLC FOR AN ADVANCE WAIVER OF RED SHIELD ACQUISITION, LLC FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN PATENT RIGHTS UNDER DOE AWARD NO. DE-EE0003364 W(A) 2010-030 The Petitioner, Red Shield Acquisition, LLC. (Red Shield), has requested a waiver of domestic and foreign patent rights for all subject inventions arising from its participation under the above-referenced award entitled "Demonstration ofan Integrated Biorefinery at Old Town, Maine." The University of Maine is a subawardee. and is not subject to this waiver request. The objective ofthis award is to develop a prototype demonstration cellulosic biorefinery that will establish and validate, on a pre-commercial scale, the extraction of hemicelluloses from wood chips and the process to convert the resultant lignocellulosic extract to biofuels and other

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

SHIELDING ESTIMATES FOR THE ANL 6.0 GeV SYNCHROTRON LIGHT SOURCE  

NLE Websites -- All DOE Office Websites (Extended Search)

SHIELDING ESTIMATES FOR THE ANL 6.0 GeV SHIELDING ESTIMATES FOR THE ANL 6.0 GeV SYNCHROTRON LIGHT SOURCE H. J. Moe V. R. Veluri LS-55-Revised Harch 1987 2 1.0 Introduction Shielding estimates for the linac, positron converter, booster synchrotron and the positron storage ring have been computed using preliminary design information. Calculations have been made of the resulting radiation for several types of operations involving normal beam loss, as well as, certain accidental beam losses. When available, experimental data from existing accelerator and light source facilities have been used in lieu of theoretical estimates. 2.0 Shielding Design Objective The Department of Energy's basic occupational exposure limit is 5 rem per year (DOE 81). However, in its guidance for maintaining exposures "as

182

Nuclear analysis and shielding optimisation in support of the ITER In-Vessel Viewing System design  

E-Print Network (OSTI)

The In-Vessel Viewing System (IVVS) units proposed for ITER are deployed to perform in-vessel examination. During plasma operations, the IVVS is located beyond the vacuum vessel, with shielding blocks envisaged to protect components from neutron damage and reduce shutdown dose rate (SDR) levels. Analyses were conducted to determine the effectiveness of several shielding configurations. The neutron response of the system was assessed using global variance reduction techniques and a surface source, and shutdown dose rate calculations were undertaken using MCR2S. Unshielded, the absorbed dose to piezoelectric motors (PZT) was found to be below stable limits, however activation of the primary closure plate (PCP) was prohibitively high. A scenario with shielding blocks at probe level showed significantly reduced PCP contact dose rate, however still marginally exceeded port cell requirements. The addition of shielding blocks at the bioshield plug demonstrated PCP contact dose rates below project requirements. SDR l...

Turner, A; Loughlin, M J; Ghani, Z; Hurst, G; Bue, A Lo; Mangham, S; Puiu, A; Zheng, S

2014-01-01T23:59:59.000Z

183

Radiation protection of staff in 111In radionuclide therapyis the lead apron shielding effective?  

Science Journals Connector (OSTI)

......trained in basic radiation safety, including the...minimise their radiation dose. Within a...the LTM Windows software, Version 1.20...shield for the radiation. Calculations...done using MatLab software. The final voxel......

M. Lyra; P. Charalambatou; M. Sotiropoulos; S. Diamantopoulos

2011-09-01T23:59:59.000Z

184

Solar shield: forecasting and mitigating space weather effects on high-voltage power transmission systems  

Science Journals Connector (OSTI)

In this paper, central elements of the Solar Shield project, launched to design and establish ... about space weather conditions to the member power utilities. EPRI also evaluates the economic impacts of ... tran...

Antti Pulkkinen; Michael Hesse; Shahid Habib; Luke Van der Zel

2010-05-01T23:59:59.000Z

185

E-Print Network 3.0 - analytic shielding optimization Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

of California at San Diego Collection: Plasma Physics and Fusion 57 Electromagnetic interference shielding reaching 70 dB in steel fiber cement Summary: content of 0.72...

186

D0 Solenoid Upgrade Project: Chimney LN2 Radiation Shield Attachment Area Calculation  

SciTech Connect

A short calculation was done to check the attachment method of the radiation shield to it's LN2 cooling tubes. The case considered was only for the obround chimney section. The proposed attachment method was to use 1/8-inch plug welds spaced every 5-inch along the length of the shield. The calculations were done conservatively for 6-inch spacing between plug welds. The criteria used was that the LN2 shield warmest temperature be less than 2 K above the temperature of the LN2 fluid. Using a very conservative heat transfer model. the calculations predict that the warmest temperature on the radiation shield will be < 1.4 K warmer than the LN2 fluid temperature.

Rucinski, R.; /Fermilab

1993-05-26T23:59:59.000Z

187

Polyethylene as a Radiation Shielding Standard in Simulated Cosmic-Ray Environments  

E-Print Network (OSTI)

High-Energy Iron Ions: Dependence on Shielding Thickness and Material,effectiveness of materials against high-energy beams (600of high-energy heavy ions than do other materials. It is

2006-01-01T23:59:59.000Z

188

Direct path from microscopic mechanics to Debye shielding, Landau damping, and wave-particle interaction  

E-Print Network (OSTI)

The derivation of Debye shielding and Landau damping from the $N$-body description of plasmas is performed directly by using Newton's second law for the $N$-body system. This is done in a few steps with elementary calculations using standard tools of calculus, and no probabilistic setting. Unexpectedly, Debye shielding is encountered together with Landau damping. This approach is shown to be justified in the one-dimensional case when the number of particles in a Debye sphere becomes large. The theory is extended to accommodate a correct description of trapping and chaos due to Langmuir waves. Shielding and collisional transport are found to be two related aspects of the repulsive deflections of electrons, in such a way that each particle is shielded by all other ones while keeping in uninterrupted motion.

Dominique F. Escande; Yves Elskens; Fabrice Doveil

2014-09-15T23:59:59.000Z

189

Geochronology of Gran Canaria, Canary Islands: Age of shield building volcanism and other magmatic phases  

Science Journals Connector (OSTI)

Forty-six new K-Ar age determinations are presented on whole rock samples and mineral separates from volcanic and subvolcanic rocks of Gran Canaria. The main subaerial shield building basaltic volcanism...3 was c...

I. McDougall; H. -U. Schmincke

1976-01-01T23:59:59.000Z

190

Gamma-Ray Shielding Effectiveness of Some Alloys for Fusion Reactor Design  

Science Journals Connector (OSTI)

The gamma-ray shielding effectiveness of some oxide dispersion-strengthen (ODS) alloys by means of mass attenuation coefficients, mean free path, exposure buildup factors and energy absorption buildup factors hav...

Vishwanath P. Singh; M. E. Medhat; N. M. Badiger

2014-10-01T23:59:59.000Z

191

Recent Economic Trends in Colorado's Oil and Gas Industry Martin Shields, Ph.D.  

E-Print Network (OSTI)

's Oil and Gas Industry Martin Shields, Ph.D. Regional Economics Institute Trends in Colorado's Oil and Gas Industry Summary Colorado's economy lost issues affecting its prospects in Colorado. Although the oil and gas industry

192

general_atomics.cdr  

NLE Websites -- All DOE Office Websites (Extended Search)

former former General Atomics Hot Cell Facility was constructed in 1959 and operated until 1991. The site encompassed approximately 7,400 square feet of laboratory and remote operations cells. Licensed operations at the facility included receipt, handling, and shipment of radioactive materials; remote handling, examination, and storage of previously irradiated nuclear fuel materials; pilot-scale tritium extraction operations; and development, fabrication, and inspection of uranium oxide-beryllium oxide fuel materials. General Atomics performed most of the work for the federal government. The General Atomics Hot Cell Facility was located in a 60-acre complex 13 miles northwest of downtown San Diego, 1 mile inland from the Pacific Ocean, and approximately 300 feet above sea level. The General Atomics site is in the center of Torrey Mesa Science Center, a 304-acre industrial

193

Uncertainties on Atomic Data  

Science Journals Connector (OSTI)

Technical Paper / Selected papers from IAEA-NFRI Technical Meeting on Data Evaluation for Atomic, Molecular and Plasma-Material Interaction Processes in Fusion, September 4-7, 2012, Daejeon, Republic of Korea

C. P. Ballance; S. D. Loch; A. R. Foster; R. K. Smith; M. C. Witthoeft; T. R. Kallman

194

Relativistic Atomic Structure Calculations  

Science Journals Connector (OSTI)

This review surveys methods for computing the electronic structures of atoms based on the use of relativistic quantum mechanics. The main mathematical formulas are presented with some account of the underlying...

Ian P. Grant

1988-01-01T23:59:59.000Z

195

general_atomics.cdr  

Office of Legacy Management (LM)

300 feet above sea level. The General Atomics site is in the center of Torrey Mesa Science Center, a 304-acre industrial park. No ground water wells are at or near the Hot Cell...

196

The Harnessed Atom | Department of Energy  

Energy Savers (EERE)

Atom The Harnessed Atom The Harnessed Atom The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on...

197

Optical imaging of Rydberg atoms .  

E-Print Network (OSTI)

??We present an experiment exploring electromagnetically induced transparency (EIT) in Rydberg atoms in order to observe optical nonlinearities at the single photon level. ??Rb atoms (more)

Mazurenko, Anton

2012-01-01T23:59:59.000Z

198

Rydberg Atoms for Quantum Information.  

E-Print Network (OSTI)

??I examine interactions between ensembles of cold Rydberg atoms, and between Rydberg atoms and an intense, optical standing wave. Because of their strong electrostatic interactions, (more)

Younge, Kelly Cooper

2010-01-01T23:59:59.000Z

199

Nuclear reactor having a polyhedral primary shield and removable vessel insulation  

DOE Patents (OSTI)

A nuclear reactor is provided having a generally cylindrical reactor vessel disposed within an opening in a primary shield. The opening in the primary shield is defined by a plurality of generally planar side walls forming a generally polyhedral-shaped opening. The reactor vessel is supported within the opening in the primary shield by reactor vessel supports which are in communication and aligned with central portions of some of the side walls. The reactor vessel is connected to the central portions of the reactor vessel supports. A thermal insulation polyhedron formed from a plurality of slidably insertable and removable generally planar insulation panels substantially surrounds at least a portion of the reactor vessel and is disposed between the reactor vessel and the side walls of the primary shield. The shape of the insulation polyhedron generally corresponds to the shape of the opening in the primary shield. Reactor monitoring instrumentation may be mounted in the corners of the opening in the primary shield between the side walls and the reactor vessel such that insulation is not disposed between the instrumentation and the reactor vessel. 5 figures.

Ekeroth, D.E.; Orr, R.

1993-12-07T23:59:59.000Z

200

Nuclear reactor having a polyhedral primary shield and removable vessel insulation  

DOE Patents (OSTI)

A nuclear reactor is provided having a generally cylindrical reactor vessel disposed within an opening in a primary shield. The opening in the primary shield is defined by a plurality of generally planar side walls forming a generally polyhedral-shaped opening. The reactor vessel is supported within the opening in the primary shield by reactor vessel supports which are in communication and aligned with central portions of some of the side walls. The reactor vessel is connected to the central portions of the reactor vessel supports. A thermal insulation polyhedron formed from a plurality of slidably insertable and removable generally planar insulation panels substantially surrounds at least a portion of the reactor vessel and is disposed between the reactor vessel and the side walls of the primary shield. The shape of the insulation polyhedron generally corresponds to the shape of the opening in the primary shield. Reactor monitoring instrumentation may be mounted in the corners of the opening in the primary shield between the side walls and the reactor vessel such that insulation is not disposed between the instrumentation and the reactor vessel.

Ekeroth, Douglas E. (Delmont, PA); Orr, Richard (Pittsburgh, PA)

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Packaging and Disposal of a Radium-beryllium Source using Depleted Uranium Polyethylene Composite Shielding  

SciTech Connect

Two, 111-GBq (3 Curie) radium-beryllium (RaBe) sources were in underground storage at the Brookhaven National Laboratory (BNL) since 1988. These sources originated from the Princeton Plasma Physics Laboratory (PPPL) where they were used to calibrate neutron detection diagnostics. In 1999, PPPL and BNL began a collaborative effort to expand the use of an innovative pilot-scale technology and bring it to full-scale deployment to shield these sources for eventual transport and burial at the Hanford Burial site. The transport/disposal container was constructed of depleted uranium oxide encapsulated in polyethylene to provide suitable shielding for both gamma and neutron radiation. This new material can be produced from recycled waste products (depleted uranium and polyethylene), is inexpensive, and can be disposed with the waste, unlike conventional lead containers, thus reducing exposure time for workers. This paper will provide calculations and information that led to the initial design of the shielding. We will also describe the production-scale processing of the container, cost, schedule, logistics, and many unforeseen challenges that eventually resulted in the successful fabrication and deployment of this shield. We will conclude with a description of the final configuration of the shielding container and shipping package along with recommendations for future shielding designs.

Keith Rule; Paul Kalb; Pete Kwaschyn

2003-02-11T23:59:59.000Z

202

The Climate Sensitivity of the Community Climate System Model Version 3 (CCSM3) JEFFREY T. KIEHL, CHRISTINE A. SHIELDS, JAMES J. HACK, AND WILLIAM D. COLLINS  

E-Print Network (OSTI)

, CHRISTINE A. SHIELDS, JAMES J. HACK, AND WILLIAM D. COLLINS National Center for Atmospheric Research

Bretherton, Chris

203

Optical atomic magnetometer  

DOE Patents (OSTI)

An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

Budker, Dmitry; Higbie, James; Corsini, Eric P

2013-11-19T23:59:59.000Z

204

Metal atomization spray nozzle  

DOE Patents (OSTI)

A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

Huxford, T.J.

1993-11-16T23:59:59.000Z

205

Atomic mass compilation 2012  

SciTech Connect

Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

Pfeiffer, B., E-mail: bpfeiffe@uni-mainz.de [II. Physikalisches Institut, Justus-Liebig-Universitt Gieen, Gieen (Germany); GSI Helmholtzzentrum fr Schwerionenforschung, Darmstadt (Germany); Venkataramaniah, K. [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India)] [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India); Czok, U. [II. Physikalisches Institut, Justus-Liebig-Universitt Gieen, Gieen (Germany)] [II. Physikalisches Institut, Justus-Liebig-Universitt Gieen, Gieen (Germany); Scheidenberger, C. [GSI Helmholtzzentrum fr Schwerionenforschung, Darmstadt (Germany) [GSI Helmholtzzentrum fr Schwerionenforschung, Darmstadt (Germany); II. Physikalisches Institut, Justus-Liebig-Universitt Gieen, Gieen (Germany)

2014-03-15T23:59:59.000Z

206

Summary of Blast Shield and Material Testing for Development of Solid Debris Collection at the National Ignition Facility (NIF)  

SciTech Connect

The ability to collect solid debris from the target chamber following a NIF shot has application for both capsule diagnostics, particularly for fuel-ablator mix, and measuring cross sections relevant to the Stockpile Stewardship program and nuclear astrophysics. Simulations have shown that doping the capsule with up to 10{sup 15} atoms of an impurity not otherwise found in the capsule does not affect its performance. The dopant is an element that will undergo nuclear activations during the NIF implosion, forming radioactive species that can be collected and measured after extraction from the target chamber. For diagnostics, deuteron or alpha induced reactions can be used to probe the fuel-ablator mix. For measuring neutron cross sections, the dopant should be something that is sensitive to the 14 MeV neutrons produced through the fusion of deuterium and tritium. Developing the collector is a challenge due to the extreme environment of the NIF chamber. The collector surface is exposed to a large photon flux from x-rays and unconverted laser light before it is exposed to a debris wind that is formed from vaporized material from the target chamber center. The photons will ablate the collector surface to some extent, possibly impeding the debris from reaching the collector and sticking. In addition, the collector itself must be mechanically strong enough to withstand the large amount of energy it will be exposed to, and it should be something that will be easy to count and chemically process. In order to select the best material for the collector, a variety of different metals have been tested in the NIF chamber. They were exposed to high-energy laser shots in order to evaluate their postshot surface characterization, morphology, degree of melt, and their ability to retain debris from the chamber center. The first set of samples consisted of 1 mm thick pieces of aluminum that had been fielded in the chamber as blast shields protecting the neutron activation diagnostic. Ten of these pieces were fielded at the equator and one was fielded on the pole. The shields were analyzed using a combination of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), x-ray fluorescence (XRF), neutron activation analysis (NAA) and chemical leaching followed by mass spectrometry. On each shield, gold debris originating from the gold hohlraum was observed, as well as large quantities of debris that were present in the center of the target chamber at the time of the shot (i.e., stainless steel, indium, copper, etc.) Debris was visible in the SEM as large blobs or splats of material that had encountered the surface of the aluminum and stuck. The aluminum itself had obviously melted and condensed, and some of the large debris splats arrived after the surface had already hardened. Melt depth was determined by cross sectioning the pieces and measuring the melted surface layers via SEM. After the SEM analysis was completed, the pieces were sent for NAA at the USGS reactor and were analyzed by U. Greife at the Colorado School of Mines. The NAA showed that the majority of gold mass present on the shields was not in the form of large blobs and splats, but was present as small particulates that had most likely formed as condensed vapor. Further analysis showed that the gold was entrained in the melted aluminum surface layers and did not extend down into the bulk of the aluminum. Once the gold mass was accounted for from the NAA, it was determined that the aluminum fielded at the equator was collecting a fraction of the total gold hohlraum mass equivalent to 120% {+-} 10% of the solid angle subtended by the shield. The attached presentation has more information on the results of the aluminum blast shield analysis. In addition to the information given in the presentation, the surfaces of the shields have been chemically leached and submitted for mass spectrometric analysis. The results from that analysis are expected to arrive after the due date of this report and will be written up at a later time. Based on the results of the aluminum b

Shaughnessy, D A; Gostic, J M; Moody, K J; Grant, P M; Lewis, L A; Hutcheon, I D

2011-11-21T23:59:59.000Z

207

ADVANTG Shielding Analysis for Closure Operations in an Open-Mode Repository  

SciTech Connect

en-mode repository concepts could require worker entry into access drifts after placement of fuel casks in order to perform activities related to backfill, plug emplacement, routine maintenance, or performance confirmation. An ideal emplacement-drift shielding configuration would minimize dose to workers while maximizing airflow through the emplacement drifts. This paper presents a preliminary investigation of the feasibility and effectiveness of radiation shielding concepts that could be employed to facilitate worker operations in an open-mode repository. The repository model for this study includes pressurized-water reactor fuel assemblies (60 GWd/MTU burnup, 40 year post-irradiation cooldown) in packages of 32 assemblies. The closest fuel packages are 5 meters from dosimetry voxels in the access drift. The unshielded dose to workers in the access drift is 73.7 rem/hour. Prior work suggests that open-mode repository concepts similar to this one would require 15 m3/s of ventilation airflow. Shielding concepts considered here include partial concrete plugs, labyrinthine shields, and stainless steel photon attenuator grids. Maximum dose to workers in the access drift was estimated for each shielding concept using MCNP5 with variance reduction parameters generated by ADVANTG. Because airflow through the shielding is important for open-mode repositories, a semi-empirical estimate of the head loss due to each shielding configuration was also calculated. Airflow and shielding performance vary widely among the proposed shielding configurations. Although the partial plug configuration had the best airflow performance, it allowed dose rates 1500 greater than the specified target. Labyrinthine shielding concepts yield doses on the order of 1 mrem/hour with configurations that impose 3 to 11 J/kg head loss. Adding 1 cm lead lining to the airflow channels of labyrinthine designs further reduces the worker dose by 65% to 95%. Photon-attenuator concepts may reduce worker dose to as low as 29 mrem/hour with head loss on the order of 1.9 J/kg.

Bevill, Aaron M [ORNL] [ORNL; Radulescu, Georgeta [ORNL] [ORNL; Scaglione, John M [ORNL] [ORNL; Howard, Rob L [ORNL] [ORNL

2013-01-01T23:59:59.000Z

208

Peaceful Uses of the Atom and Atoms for Peace  

Office of Scientific and Technical Information (OSTI)

Peaceful Uses of the Atom Peaceful Uses of the Atom Fermi and Atoms for Peace · Understanding the Atom · Seaborg · Teller Atoms for Peace Atoms for Peace + 50 - Conference, October 22, 2003 Celebrating the 50th anniversary of President Eisenhower's "Atoms for Peace" speech to the UN General Assembly Atoms for Peace (video 12:00 Minutes) Atoms for Peace Address given by Dwight D. Eisenhower before the General Assembly of the United Nations, New York City, December 8, 1953 Documents: Atomic Power in Space: A History A history of the Space Isotope Power Program of the United States from the mid-1950s through 1982; interplanetary space exploration successes and achievements have been made possible by this technology. Establishing Site X: Letter, Arthur H. Compton to Enrico Fermi, September 14, 1942

209

Lesson 3- Atoms and Isotopes  

Energy.gov (U.S. Department of Energy (DOE))

Youve probably heard people refer to nuclear energy as atomic energy. Why? Nuclear energy is the energy that is stored in the bonds of atoms, inside the nucleus. Nuclear power plants are designed to capture this energy as heat and convert it to electricity. This lesson looks closely at what atoms are and how atoms store energy.

210

Educational Multiwavelength Atomic Emission Spectrometer  

E-Print Network (OSTI)

atomic absorption is the capability for simultaneous multielement analysis. It can be used colleges had acquired atomic absorption instruments by the year 1990.[2] In contrast, atomic emission with the acetylene-air flame source taken from an existing atomic absorption instrument. Two spectrometer units

Nazarenko, Alexander

211

general_atomics.cdr  

Office of Legacy Management (LM)

former General former General Atomics Hot Cell Facility was constructed in 1959 and operated until 1991. The site encompassed approximately 7,400 square feet of laboratory and remote operations cells. Licensed operations at the facility included receipt, handling, and shipment of radioactive materials; remote handling, examination, and storage of previously irradiated nuclear fuel materials; pilot-scale tritium extraction operations; and development, fabrication, and inspection of uranium oxide-beryllium oxide fuel materials. General Atomics performed most of the work for the federal government. The General Atomics Hot Cell Facility was located in a 60-acre complex 13 miles northwest of downtown San Diego, 1 mile inland from the Pacific Ocean, and approximately 300 feet above sea level.

212

Iowa Powder Atomization Technologies  

SciTech Connect

The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

None

2012-01-01T23:59:59.000Z

213

Atomic Josephson vortices  

SciTech Connect

We show that Josephson vortices in a quasi-one-dimensional atomic Bose Josephson junction can be controllably manipulated by imposing a difference of chemical potentials on the atomic Bose-Einstein condensate waveguides forming the junction. This effect, which has its origin in the Berry phase structure of a vortex, turns out to be very robust in the whole range of the parameters where such vortices can exist. We also propose that a Josephson vortex can be created by the phase imprinting technique and can be identified by a specific tangential feature in the interference picture produced by expanding clouds released from the waveguides.

Kaurov, V. M.; Kuklov, A. B. [Department of Engineering Science and Physics, College of Staten Island, CUNY, Staten Island, New York 10314 (United States)

2006-01-15T23:59:59.000Z

214

Atomic Force Microscope  

SciTech Connect

The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

Day, R.D.; Russell, P.E.

1988-12-01T23:59:59.000Z

215

Biological shield design and analysis of KIPT accelerator-driven subcritical facility.  

SciTech Connect

Argonne National Laboratory of the United States and Kharkov Institute of Physics and Technology of Ukraine have been collaborating on the conceptual design development of an electron accelerator-driven subcritical facility. The facility will be utilized for performing basic and applied nuclear research, producing medical isotopes, and training young nuclear specialists. This paper presents the design and analyses of the biological shield performed for the top section of the facility. The neutron source driving the subcritical assembly is generated from the interaction of a 100-kW electron beam with a natural uranium target. The electron energy is in the range of 100 to 200 MeV, and it has a uniform spatial distribution. The shield design and the associated analyses are presented including different parametric studies. In the analyses, a significant effort was dedicated to the accurate prediction of the radiation dose outside the shield boundary as a function of the shield thickness without geometrical approximations or material homogenization. The MCNPX Monte Carlo code was utilized for the transport calculation of electrons, photons, and neutrons. Weight window variance-reduction techniques were introduced, and the dose equivalent outside the shield can be calculated with reasonably good statistics.

Zhong, Z.; Gohar, Y.; Nuclear Engineering Division

2009-12-01T23:59:59.000Z

216

Safety analysis report for the National Low-Temperature Neutron Irradiation Facility (NLTNIF) at the ORNL Bulk Shielding Reactor (BSR)  

SciTech Connect

This report provides information concerning: the experiment facility; experiment assembly; instrumentation and controls; materials; radioactivity; shielding; thermodynamics; estimated or measured reactivity effects; procedures; hazards; and quality assurance. (JDB)

Coltman, R.R. Jr.; Kerchner, H.R.; Klabunde, C.E.; Richardson, S.A.

1986-06-01T23:59:59.000Z

217

Liquid Metal Reactor Program: JASPER US/DOE/PNC Shielding Research Program : Technical progress report, April 1-May 31, 1987  

SciTech Connect

This progress report details activities on the JASPER Shielding Program for the time period of April 1, 1987 through May 31, 1987.

Ingersoll, D.T.; Engle, W.W.; Muckenthaler, F.J.; Slater, C.O.

1987-12-31T23:59:59.000Z

218

Mossbauer Spectroscopic Study of Gamma Irradiation on the Structural Properties of Hematite, Magnetite and Limonite Concrete for Nuclear Reactor Shielding  

Science Journals Connector (OSTI)

This work investigate the effect of gamma irradiation on a heavy type of concrete, constructed for nuclear reactor shield. The effect of gamma irradiation was...

N.A. Eissa; M.S.I. Kany; A.S. Mohamed; A.A. Sallam; M.H. El Fouly

219

Atomic Scientists Brief Congress  

Science Journals Connector (OSTI)

Topics covered included underground explosions to produce energy, chemicals, or petroleum; advanced reactors capable of producing chemicals; atomic power for space propulsion; direct conversion of heat energy to electricity; and controlled thermonuclear reactions. ... (For details on controlled fusion research see page 46.) ...

1960-04-04T23:59:59.000Z

220

Atomic Power in Japan  

Science Journals Connector (OSTI)

NUCLEAR ENERGY will provide most of the power requirements in Japan by the end of this century. So predicts Charles H. Weaver, vice president in charge of atomic power activities for Westinghouse Electric.Addressing the Conference on Peaceful Uses of ...

1957-05-27T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Bohr's model: Extreme atoms  

Science Journals Connector (OSTI)

... by bombarding atoms with accelerated protons, then slow them down by passing them through metallic foil, cool them with cold electrons and trap them with electromagnetic fields. A similar trap ... Curiosity and national pride undoubtedly have a role, with politicians and scientists both looking to stamp their country's name into a new box on the periodic table. But each ...

Richard Van Noorden

2013-06-05T23:59:59.000Z

222

Magnetism and Atomic Structure  

Science Journals Connector (OSTI)

... the information with regard to the atom has been obtained by studying spectra; chemistry, magnetism, X-ray scattering, etc., play only a subsidiary part. We must admit, ... for fresh sources of information. Much may be said in support of the opinion that magnetism will open a new way by which to approach the study of the structure of ...

P. KAPITZA

1927-06-04T23:59:59.000Z

223

Factsheet Overview The Savannah River National Laboratory's Shielded Cells Facility gives the  

NLE Websites -- All DOE Office Websites (Extended Search)

Overview Overview The Savannah River National Laboratory's Shielded Cells Facility gives the laboratory the ability to safely work with a wide variety of highly radioactive samples and items in support of various research and development initiatives. Skilled operators, standing safely outside the cells, use manipulator arms to perform work inside the cells. The facility consists of sixteen 6-foot by 6-foot work stations or cells with the following features: The exterior walls of the facility are made of 3-foot-thick high-density * concrete with a 1/8-inch thick stainless steel liner. Each cell has a 3' x3' shielding window. Shielding windows are 3-foot thick * leaded glass, filled with mineral oil for optimal viewing capabilities.

224

ANL/APS/TB-21 Radiation Shielding of Insertion Device Beamlines  

NLE Websites -- All DOE Office Websites (Extended Search)

1 1 Radiation Shielding of Insertion Device Beamlines Using a Mirror as the First Optical Element W. Yun, B. Lai, K. J. Randall, S. Davey, D. R. Haeffner, P. K. Job, and D. Shu February 1995 Abstract The radiation shielding for an Advanced Photon Source (APS) insertion device beamline using a mirror as the first optical component is discussed. The beamline layout for a specific Synchrotron Radiation Instrumentation Collaborative Access Team beamline (sector 2 of SRI CAT) is described, and the methodology used to determine the radiation shielding is presented. Results indicate that, by using a x-ray mirror with a critical energy of 32 keV for total reflection, an undulator beam containing nearly all x-rays in the 0 - 32 keV spectral range can be delivered

225

A large-scale magnetic shield with 10^6 damping at milli-Hertz frequencies  

E-Print Network (OSTI)

A magnetically shielded environment with a damping factor larger than one million at the milli-Hertz frequency regime and an extremely low field and gradient over an extended volume is presented. This extraordinary shielding perfomance is to our knowledge unprecedented and represents an improvement of the state of the art in damping the difficult regime of very low-frequency distortions by more than an order of magnitude. Thus, a new generation of high precision measurements in fundamental physics and metrology is enabled with this technology, particularly suitable to find traces of new physics far beyond the reach of accelerator based physics. The technical realization of the shield with its improvements in design is discussed.

Altarev, I; Beck, D H; Chupp, T; Fierlinger, K; Fierlinger, P; Kuchler, F; Lins, T; Marino, M G; Niessen, B; Petzoldt, G; Singh, J T; Schlpfer, U; Schnabel, A; Stoepler, R; Stuiber, S; Strum, M; Taubenheim, B; Voigt, J

2015-01-01T23:59:59.000Z

226

High Rydberg Atoms: Newcomers to the Atomic Physics Scene  

Science Journals Connector (OSTI)

...HYDROGEN ATOM, NUCLEAR FUSION 5 : 41 ( 1965 ). BAYFIELD...HIGHLY-EXCITED KR ATOMS BY HF AND HCL MOLECULES, BULLETIN...USING A CW TUNABLE DYE LASER, PHYSICAL REVIEW LETTERS...such diverse fields as laser development, laser isotopeseparation, energy...

Ronald F. Stebbings

1976-08-13T23:59:59.000Z

227

Multidimensional shielding analysis of the JASPER in-vessel fuel storage experiments  

SciTech Connect

The In-Vessel Fuel Storage (IVFS) experiments analyzed in this report were conducted at the Oak Ridge National Laboratory`s Tower Shielding Reactor (TSR) as part of the Japanese-American Shielding Program for Experimental Research (JASPER). These IVFS experiments were designed to study source multiplication and three-dimensional effects related to in-vessel storage of spent fuel elements in liquid metal reactor (LMR) systems. The present report describes the 2-D and 3-D models, analyses, and calculated results corresponding to a limited subset of those IVFS experiments in which the US LMR program has a particular interest.

Bucholz, J.A.

1993-03-01T23:59:59.000Z

228

Oxy-nitroso shielding burst model of cold atmospheric plasma therapeutics  

Science Journals Connector (OSTI)

Abstract It is postulated that cold atmospheric plasma (CAP) can trigger a therapeutic shielding response in tissue by creating a time- and space-localized, burst-like form of oxy-nitrosative stress on near-surface exposed cells through the flux of plasma-generated reactive oxygen and nitrogen species (RONS). RONS-exposed surface layers of cells communicate to the deeper levels of tissue via a form of the bystander effect, similar to responses to other forms of cell stress. In this proposed model of CAP therapeutics, the plasma stimulates a cellular survival mechanism through which aerobic organisms shield themselves from infection and other challenges.

David B Graves

2014-01-01T23:59:59.000Z

229

Evaluation of the effectiveness of shielding and filtering of HVDC converter stations  

SciTech Connect

The electromagnetic interference (EMI) generated by the periodic turn-on and turn-off of the valves is an important consideration in the design of HVDC converter stations. Remedial measures such as shielding the valve hall and filtering have been used in order to reduce the interference levels to acceptable values. The application of recently-developed Numerical Electromagnetic Code (NEC) to the problem of EMI from HVDC converter stations is investigated in this paper, with particular emphasis on evaluating the effectiveness of valve hall shielding and filtering.

Dallaire, R.D.; Maruvada, P.S.

1989-04-01T23:59:59.000Z

230

Graphite-ceramic rf Faraday-thermal shield and plasma limiter  

DOE Patents (OSTI)

The present invention is directed to a brazing procedure for joining a ceramic or glass material (e.g., Al/sub 2/O/sub 3/ or Macor) to graphite. In particular, the present invention is directed to a novel brazing procedure for the production of a brazed ceramic graphite product useful as a Faraday shield. The brazed ceramic graphite Faraday shield of the present invention may be used in Magnetic Fusion Devices (e.g., Princeton Large Torus Tokamak) or other high temperature resistant apparatus.

Hwang, D.L.Q.; Hosea, J.C.

1983-05-05T23:59:59.000Z

231

Nucleonic analysis of a preliminary design for the ETF neutral-beam-injector duct shielding  

SciTech Connect

A nucleonic analysis of the Engineering Test Facility Neutral-Beam-Injector duct shielding has been made using a hybrid Monte Carlo/discrete-ordinates method. This method used Monte Carlo to determine internal and external boundary surface sources for a subsequent discrete-ordinates calculation of the neutron and gamma-ray transport through the shield. The analysis also included determination of the energy and angular distribution of neutrons and gamma rays entering the duct from the torus plasma chamber. Confidence in the hybrid method and the results obtained were provided through a comparison with three-dimensional Monte Carlo results.

Urban, W.T.; Seed, T.J.; Dudziak, D.J.

1980-01-01T23:59:59.000Z

232

Optical imaging of Rydberg atoms  

E-Print Network (OSTI)

We present an experiment exploring electromagnetically induced transparency (EIT) in Rydberg atoms in order to observe optical nonlinearities at the single photon level. ??Rb atoms are trapped and cooled using a magneto-optical ...

Mazurenko, Anton

2012-01-01T23:59:59.000Z

233

Seaborg Predicts Bright Atomic Future  

Science Journals Connector (OSTI)

Seaborg Predicts Bright Atomic Future ... To explore both the immediate and long-term ramifications of the cutbacks, C&EN talked to the Chairman of the Atomic Energy Commission, Dr. Glenn T. Seaborg . ...

1964-06-15T23:59:59.000Z

234

Shielding analysis and design of the KIPT experimental neutron source facility of Ukraine.  

SciTech Connect

Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the conceptual design development of an experimental neutron source facility based on the use of an electron accelerator driven subcritical (ADS) facility [1]. The facility uses the existing electron accelerators of KIPT in Ukraine. The neutron source of the sub-critical assembly is generated from the interaction of 100 KW electron beam with a natural uranium target. The electron beam has a uniform spatial distribution and the electron energy in the range of 100 to 200 MeV, [2]. The main functions of the facility are the production of medical isotopes and the support of the Ukraine nuclear power industry. Reactor physics experiments and material performance characterization will also be carried out. The subcritical assembly is driven by neutrons generated by the electron beam interactions with the target material. A fraction of these neutrons has an energy above 50 MeV generated through the photo nuclear interactions. This neutron fraction is very small and it has an insignificant contribution to the subcritical assembly performance. However, these high energy neutrons are difficult to shield and they can be slowed down only through the inelastic scattering with heavy isotopes. Therefore the shielding design of this facility is more challenging relative to fission reactors. To attenuate these high energy neutrons, heavy metals (tungsten, iron, etc.) should be used. To reduce the construction cost, heavy concrete with 4.8 g/cm{sup 3} density is selected as a shielding material. The iron weight fraction in this concrete is about 0.6. The shape and thickness of the heavy concrete shield are defined to reduce the biological dose equivalent outside the shield to an acceptable level during operation. At the same time, special attention was give to reduce the total shield mass to reduce the construction cost. The shield design is configured to maintain the biological dose equivalent during operation {le} 0.5 mrem/h inside the subcritical hall, which is five times less than the allowable dose for working forty hours per week for 50 weeks per year. This study analyzed and designed the thickness and the shape of the radial and top shields of the neutron source based on the biological dose equivalent requirements inside the subcritical hall during operation. The Monte Carlo code MCNPX is selected because of its capabilities for transporting electrons, photons, and neutrons. Mesh based weight windows variance reduction technique is utilized to estimate the biological dose outside the shield with good statistics. A significant effort dedicated to the accurate prediction of the biological dose equivalent outside the shield boundary as a function of the shield thickness without geometrical approximations or material homogenization. The building wall was designed with ordinary concrete to reduce the biological dose equivalent to the public with a safety factor in the range of 5 to 20.

Zhong, Z.; Gohar, M. Y. A.; Naberezhnev, D.; Duo, J.; Nuclear Engineering Division

2008-10-31T23:59:59.000Z

235

Phanerozoic tectonothermal history of the ArabianNubian shield in the Eastern Desert of Egypt: evidence from fission track  

E-Print Network (OSTI)

Phanerozoic tectonothermal history of the Arabian­Nubian shield in the Eastern Desert of Egypt were performed in the Eastern Desert of Egypt. The results provide insights into the processes driving reserved. Keywords: Phanerozoic; Fission track thermochronology; Palaeostress; Arabian­Nubien shield; Egypt

Fritz, Harald

236

Appendix G: Radiation HYDROGEN ATOM  

E-Print Network (OSTI)

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix G: Radiation #12;#12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

237

Appendix A: Radiation HYDROGEN ATOM  

E-Print Network (OSTI)

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix A: Radiation #12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

238

Recent Progress in ultracold atoms  

E-Print Network (OSTI)

and Einstein What is Bose-Einstein condensation (BEC)? #12;300 K to 1 mK 109 atoms 1 mK to 1 mK 108 106 atoms How to make a BEC: Cool atoms at ultra low temperature Laser beams Fluorescence Laser cooling (Doppler

Baltisberger, Jay H.

239

VARIOUS APPLICATIONS OF ZEEMAN ATOMIC ABSORPTION SPECTROSCOPY  

E-Print Network (OSTI)

APPLICATIONS OF ZEEMAN ATOMIC ABSORPTION SPECTROSCOPYthe Zeeman effect to atomic absorption spectroscopy has beenthe Zeeman effect on atomic absorption spectrometry has been

Koizumi, Hideaki

2011-01-01T23:59:59.000Z

240

Experimental Test of Self-Shielding in VUV Photodissociation of CO  

NLE Websites -- All DOE Office Websites (Extended Search)

Experimental Test of Self-Shielding in VUV Photodissociation of CO Print Experimental Test of Self-Shielding in VUV Photodissociation of CO Print One way to test models of the solar system's formation is to compare the isotopic abundances of the elements found in its constituent bodies. A case in point is oxygen with three stable isotopes dominated by oxygen-16, with minute fractions of oxygen-17 and oxygen-18. Primitive objects whose formation predates the Earth's, such as the calcium-aluminum-rich inclusions in the Allende meteorite, have relatively lower fractions of the two heavier isotopes than does the Earth's crust. Among the numerous explanations that have been proposed is the notion that chemical processes within the early solar nebula gave rise to the oxygen ratios, a leading candidate being a process called isotope self-shielding. But researchers at the University of California, San Diego, and Berkeley Lab have now shown that photodissociation of carbon monoxide (CO) caused by vacuum-ultraviolet (VUV) light from the early sun could generate reservoirs of the heavier isotopes in the solar nebula without the help of self-shielding.

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Experimental Test of Self-Shielding in VUV Photodissociation of CO  

NLE Websites -- All DOE Office Websites (Extended Search)

Experimental Test of Self-Shielding in VUV Photodissociation of CO Print Experimental Test of Self-Shielding in VUV Photodissociation of CO Print One way to test models of the solar system's formation is to compare the isotopic abundances of the elements found in its constituent bodies. A case in point is oxygen with three stable isotopes dominated by oxygen-16, with minute fractions of oxygen-17 and oxygen-18. Primitive objects whose formation predates the Earth's, such as the calcium-aluminum-rich inclusions in the Allende meteorite, have relatively lower fractions of the two heavier isotopes than does the Earth's crust. Among the numerous explanations that have been proposed is the notion that chemical processes within the early solar nebula gave rise to the oxygen ratios, a leading candidate being a process called isotope self-shielding. But researchers at the University of California, San Diego, and Berkeley Lab have now shown that photodissociation of carbon monoxide (CO) caused by vacuum-ultraviolet (VUV) light from the early sun could generate reservoirs of the heavier isotopes in the solar nebula without the help of self-shielding.

242

Experimental Test of Self-Shielding in VUV Photodissociation of CO  

NLE Websites -- All DOE Office Websites (Extended Search)

Experimental Test of Experimental Test of Self-Shielding in VUV Photodissociation of CO Experimental Test of Self-Shielding in VUV Photodissociation of CO Print Wednesday, 25 March 2009 00:00 One way to test models of the solar system's formation is to compare the isotopic abundances of the elements found in its constituent bodies. A case in point is oxygen with three stable isotopes dominated by oxygen-16, with minute fractions of oxygen-17 and oxygen-18. Primitive objects whose formation predates the Earth's, such as the calcium-aluminum-rich inclusions in the Allende meteorite, have relatively lower fractions of the two heavier isotopes than does the Earth's crust. Among the numerous explanations that have been proposed is the notion that chemical processes within the early solar nebula gave rise to the oxygen ratios, a leading candidate being a process called isotope self-shielding. But researchers at the University of California, San Diego, and Berkeley Lab have now shown that photodissociation of carbon monoxide (CO) caused by vacuum-ultraviolet (VUV) light from the early sun could generate reservoirs of the heavier isotopes in the solar nebula without the help of self-shielding.

243

Experimental Test of Self-Shielding in VUV Photodissociation of CO  

NLE Websites -- All DOE Office Websites (Extended Search)

Experimental Test of Self-Shielding in VUV Photodissociation of CO Print Experimental Test of Self-Shielding in VUV Photodissociation of CO Print One way to test models of the solar system's formation is to compare the isotopic abundances of the elements found in its constituent bodies. A case in point is oxygen with three stable isotopes dominated by oxygen-16, with minute fractions of oxygen-17 and oxygen-18. Primitive objects whose formation predates the Earth's, such as the calcium-aluminum-rich inclusions in the Allende meteorite, have relatively lower fractions of the two heavier isotopes than does the Earth's crust. Among the numerous explanations that have been proposed is the notion that chemical processes within the early solar nebula gave rise to the oxygen ratios, a leading candidate being a process called isotope self-shielding. But researchers at the University of California, San Diego, and Berkeley Lab have now shown that photodissociation of carbon monoxide (CO) caused by vacuum-ultraviolet (VUV) light from the early sun could generate reservoirs of the heavier isotopes in the solar nebula without the help of self-shielding.

244

Experimental Test of Self-Shielding in VUV Photodissociation of CO  

NLE Websites -- All DOE Office Websites (Extended Search)

Experimental Test of Self-Shielding in VUV Photodissociation of CO Print Experimental Test of Self-Shielding in VUV Photodissociation of CO Print One way to test models of the solar system's formation is to compare the isotopic abundances of the elements found in its constituent bodies. A case in point is oxygen with three stable isotopes dominated by oxygen-16, with minute fractions of oxygen-17 and oxygen-18. Primitive objects whose formation predates the Earth's, such as the calcium-aluminum-rich inclusions in the Allende meteorite, have relatively lower fractions of the two heavier isotopes than does the Earth's crust. Among the numerous explanations that have been proposed is the notion that chemical processes within the early solar nebula gave rise to the oxygen ratios, a leading candidate being a process called isotope self-shielding. But researchers at the University of California, San Diego, and Berkeley Lab have now shown that photodissociation of carbon monoxide (CO) caused by vacuum-ultraviolet (VUV) light from the early sun could generate reservoirs of the heavier isotopes in the solar nebula without the help of self-shielding.

245

SPACE WEATHER, VOL. ???, XXXX, DOI:10.1029/, Stormer Theory Applied to Magnetic Spacecraft Shielding  

E-Print Network (OSTI)

Shielding S. G. Shepherd1 and B. T. Kress2 Abstract. The existence of a toroidal region from which charged of a deployed su- perconducting coil is in error [c.f., Shepherd and Kress, 2007]. The authors of these studies

Shepherd, Simon

246

Progress In Electromagnetics Research B, Vol. 15, 197215, 2009 MODELING OF SHIELDING COMPOSITE MATERIALS  

E-Print Network (OSTI)

Progress In Electromagnetics Research B, Vol. 15, 197­215, 2009 MODELING OF SHIELDING COMPOSITE B. Archambeault IBM Co. Research Triangle Park, NC, USA Abstract--Composites containing conducting structures are studied, with both absorbing and reflecting composite layers. In this paper, fiber

Koledintseva, Marina Y.

247

Nicole Hudson Sillerman Center Summer Internship at the Blue Cross Blue Shield of Massachusetts Foundation  

E-Print Network (OSTI)

Foundation Reflection Paper As a result of the generosity of the Sillerman Center for the Advancement of Philanthropy, I had the privilege of interning at The Blue Cross Blue Shield of Massachusetts Foundation (the Foundation) during the summer of 2011. The Foundation was founded in 2001 with an endowment from Blue Cross

Snider, Barry B.

248

Stratigraphy of small shield volcanoes on Venus: Criteria for determining stratigraphic relationships and assessment of relative  

E-Print Network (OSTI)

than about 20 km, are common and sometimes very abundant features on the plains of Venus. Typically plains of Venus. Did the eruption style of small shields occur repeatedly throughout the visible part plains with wrinkle ridges. Fifteen fields ($11%) appear to be synchronous with regional plains

Head III, James William

249

The City of Vancouver's Approach to Electric Vehicles: Malcolm Shield, Climate Policy Manager  

E-Print Network (OSTI)

' Drives, Community Events, EV Ambassadors #12;Thank-you! 10 10 Questions? #12;Electric Vehicles: Timeline1 The City of Vancouver's Approach to Electric Vehicles: 7 Pillars Malcolm Shield, Climate Policy. Integrated EV Charging and Cellular Infrastructure Trial 6 #12;5. CoV Fleet EVs 7 · First Mitsubishi Electric

California at Davis, University of

250

The trade experiment: shielding calculations for the building hosting the subcritical system  

Science Journals Connector (OSTI)

......Italy), a pool reactor of 1 MW thermal...the feasibility analysis is played by radioprotection...to a traditional reactor owing to the presence...Utilisation and Reliability of High Power Proton...calculations in the reactor building. TRADE...Summary hazard analysis and shielding studies......

K. W. Burn; M. Carta; L. Casalini; Y. Kadi; S. Monti; E. Nava; M. Palomba; C. Petrovich; L. Picardi; C. Rubbia; F. Troiani

2005-12-20T23:59:59.000Z

251

Shielding Evaluation of Plutonium and Uranium Contents in 9975 Shipping Containers  

SciTech Connect

Shielding evaluations were performed in support of developing the Safety Analysis Report for Packagings (SARP) for the 9975 Shipping container. The objective of these evaluations was to demonstrate compliance with the performance requirements specified in federal regulations for each content envelope.

Vincent, A.

2003-01-27T23:59:59.000Z

252

Summary of Surface Swipe Sampling for Beryllium on Lead Bricks and Shielding  

SciTech Connect

Approximately 25,000 lbs of lead bricks at Site 300 were assessed by the Site 300 Industrial Hygienis tand Health Physicist for potential contamination of beryllium and radiation for reuse. These lead bricks and shielding had been used as shielding material during explosives tests that included beryllium and depleted uranium. Based on surface swipe sampling that was performed between July 26 and October 11, 2010, specifically for beryllium, the use of a spray encapsulant was found to be an effective means to limit removable surface contamination to levels below the DOE release limit for beryllium, which is 0.2 mcg/100 cm{sup 2}. All the surface swipe sampling data for beryllium and a timeline of when the samples were collected (and a brief description) are presented in this report. On December 15, 2010, the lead bricks and shielding were surveyed with an ion chamber and indicated dose rates less than 0.05 mrem per hour on contact. This represents a dose rate consistent with natural background. An additional suevey was performed on February 8, 2011, using a GM survey instrument to estimate total activity on the lead bricks and shielding, confirming safe levels of radioactivity. The vendor is licensed to possess and work with radioactive material.

Paik, S Y; Barron, D A

2011-08-03T23:59:59.000Z

253

Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams  

E-Print Network (OSTI)

Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams (Received 24 March 2010; published 14 October 2010) We investigate the use of energetic electron beams beam (with energy >100 MeV) was generated by the process of laser-wakefield acceleration through

Umstadter, Donald

254

ShieldGen: Automatic Data Patch Generation for Unknown Vulnerabilities with Informed Probing  

E-Print Network (OSTI)

ShieldGen: Automatic Data Patch Generation for Unknown Vulnerabilities with Informed Probing generating a data patch or a vulnerability signature for an unknown vulnerability, given a zero-day attack. In this paper, we aim to automate this process and enable fast, patch-level pro- tection generation

Locasto, Michael E.

255

Macroscopic erosion of plasma facing and nearby components during plasma instabilities: the droplet shielding phenomenon  

E-Print Network (OSTI)

be extremely high. This can severely limit divertor system lifetime to only a few disruptions. Ablation is mass; Shielding; Lifetime; HEIGHTS package 1. Introduction During plasma disruptions, the power ¯ux reaching to the reduced radiation power for a reasonable disruption frequency. However, mass losses due to ablation can

Harilal, S. S.

256

Optimized optomechanical crystal cavity with acoustic radiation shield Jasper Chan, Amir H. Safavi-Naeini, Jeff T. Hill, Sen Meenehan, and Oskar Painter  

E-Print Network (OSTI)

Optimized optomechanical crystal cavity with acoustic radiation shield Jasper Chan, Amir H. Safavi://apl.aip.org/about/rights_and_permissions #12;Optimized optomechanical crystal cavity with acoustic radiation shield Jasper Chan, Amir H. Safavi

Painter, Oskar

257

Radiation attenuation by lead and nonlead materials used in radiation shielding garments  

SciTech Connect

The attenuating properties of several types of lead (Pb)-based and non-Pb radiation shielding materials were studied and a correlation was made of radiation attenuation, materials properties, calculated spectra and ambient dose equivalent. Utilizing the well-characterized x-ray and gamma ray beams at the National Research Council of Canada, air kerma measurements were used to compare a variety of commercial and pre-commercial radiation shielding materials over mean energy ranges from 39 to 205 keV. The EGSnrc Monte Carlo user code cavity.cpp was extended to provide computed spectra for a variety of elements that have been used as a replacement for Pb in radiation shielding garments. Computed air kerma values were compared with experimental values and with the SRS-30 catalogue of diagnostic spectra available through the Institute of Physics and Engineering in Medicine Report 78. In addition to garment materials, measurements also included pure Pb sheets, allowing direct comparisons to the common industry standards of 0.25 and 0.5 mm 'lead equivalent'. The parameter 'lead equivalent' is misleading, since photon attenuation properties for all materials (including Pb) vary significantly over the energy spectrum, with the largest variations occurring in the diagnostic imaging range. Furthermore, air kerma measurements are typically made to determine attenuation properties without reference to the measures of biological damage such as ambient dose equivalent, which also vary significantly with air kerma over the diagnostic imaging energy range. A single material or combination cannot provide optimum shielding for all energy ranges. However, appropriate choice of materials for a particular energy range can offer significantly improved shielding per unit mass over traditional Pb-based materials.

McCaffrey, J. P.; Shen, H.; Downton, B.; Mainegra-Hing, E. [Ionizing Radiation Standards, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada)

2007-02-15T23:59:59.000Z

258

On neutron numbers and atomic masses  

Science Journals Connector (OSTI)

On neutron numbers and atomic masses ... Assigning neutron numbers, correct neutron numbers, and atomic masses and nucleon numbers. ...

R. Heyrovsk

1992-01-01T23:59:59.000Z

259

Atomic Energy Commission Takes Over Responsibility for all Atomic...  

National Nuclear Security Administration (NNSA)

Takes Over Responsibility for all Atomic Energy Programs | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

260

Magnetic trap for thulium atoms  

SciTech Connect

For the first time ultra-cold thulium atoms were trapped in a magnetic quadrupole trap with a small field gradient (20 Gs cm{sup -1}). The atoms were loaded from a cloud containing 4x10{sup 5} atoms that were preliminarily cooled in a magneto-optical trap to the sub-Doppler temperature of 80 {mu}K. As many as 4x10{sup 4} atoms were trapped in the magnetic trap at the temperature of 40 {mu}K. By the character of trap population decay the lifetime of atoms was determined (0.5 s) and an upper estimate was obtained for the rate constant of inelastic binary collisions for spin-polarised thulium atoms in the ground state (g{sub in} < 10{sup -11}cm{sup 3} s{sup -1}). (magnetic traps)

Sukachev, D D; Sokolov, A V; Chebakov, K A; Akimov, A V; Kolachevskii, N N; Sorokin, Vadim N [P N Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2011-08-31T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Probing the Short Range Spin Dependent Interactions by Polarized $^{3}He$ Atom Beams  

E-Print Network (OSTI)

Experiments using polarized $^{3}He$ atom beams to search for short range spin dependent forces are proposed. High intensity, high polarization, small beam size $^{3}He$ atom beams have been successfully produced and used in surface science researches. By incorporating background reduction designs as combination shielding by $\\mu$-metal and superconductor and double beam pathes, the precision of spin rotation angle per unit length could be improved by a factor of $\\sim10^{4}$. By this precision, in combination with using a high density and low magnetic susceptibility sample source mass,and reversing one beam path if necessary, sensitivities on three different types of spin dependent interactions could be possibly improved by as much as $\\sim10^{2}$ to $\\sim10^{8}$ over the current experiments at the millimeter range.

Yan, H

2014-01-01T23:59:59.000Z

262

Probing the Short Range Spin Dependent Interactions by Polarized $^{3}He$ Atom Beams  

E-Print Network (OSTI)

Experiments using polarized $^{3}He$ atom beams to search for short range spin dependent forces are proposed. High intensity, high polarization, small beam size $^{3}He$ atom beams have been successfully produced and used in surface science researches. By incorporating background reduction designs as combination shielding by $\\mu$-metal and superconductor and double beam pathes, the precision of spin rotation angle per unit length could be improved by a factor of $\\sim10^{4}$. By this precision, in combination with using a high density and low magnetic susceptibility sample source mass,and reversing one beam path if necessary, sensitivities on three different types of spin dependent interactions could be possibly improved by as much as $\\sim10^{2}$ to $\\sim10^{8}$ over the current experiments at the millimeter range.

H. Yan

2014-07-22T23:59:59.000Z

263

High efficiency direct detection of ions from resonance ionization of sputtered atoms  

DOE Patents (OSTI)

A method and apparatus are provided for trace and other quantitative analysis with high efficiency of a component in a sample, with the analysis involving the removal by ion or other bombardment of a small quantity of ion and neutral atom groups from the sample, the conversion of selected neutral atom groups to photoions by laser initiated resonance ionization spectroscopy, the selective deflection of the photoions for separation from original ion group emanating from the sample, and the detection of the photoions as a measure of the quantity of the component. In some embodiments, the original ion group is accelerated prior to the RIS step for separation purposes. Noise and other interference are reduced by shielding the detector from primary and secondary ions and deflecting the photoions sufficiently to avoid the primary and secondary ions.

Gruen, D.M.; Pellin, M.J.; Young, C.E.

1985-01-16T23:59:59.000Z

264

ATOMIC ENERGY COMMISSION  

Office of Legacy Management (LM)

' ' ATOMIC ENERGY COMMISSION Frank K. Pittman, Director, bivisioa of Waste &&gement and s- portation, Headquarters j CONTAMItUTED RX-AEC-OWNED OR LEASED FACILITIES' This memorandum responds to your TWX certain information on the above subject. the documentation necessary to answer your available due to the records disposal vailing at the time of release or From records that are available and from disc&ions with most familiar with the transfer operations, &have the current radiological conditibn of transferred property is adequate under present standards. The following tabulations follow the format suggested in your TWX and are grouped to an operations or contract r+ponsibility. A,I Ex-AEC Storage Sites - I r:/ National Stockpile Site '(NSS) and OperatEonal

265

Bettis Atomic Power Laboratory  

SciTech Connect

The Bettis Atomic Power Laboratory (Bettis) is owned by the US Department of Energy (DOE) and has been operated under Government contract by the Westinghouse Electric Corporation since 1949. The Bettis Site in West Mifflin, Pennsylvania conducts research and development work on improved nuclear propulsion plants for US Navy warships and is the headquarters for all of the Laboratory's operations. For many years, environmental monitoring has been performed to demonstrate that the Bettis Site is being operated in accordance with environmental standards. While the annual report describes monitoring practices and results, it does not describe the nature and environmental aspects of work and facilities at the Bettis Site nor give a historical perspective of Bettis' operations. The purpose of this report is to provide this information as well as background information, such as the geologic and hydrologic nature of the Bettis Site, pertinent to understanding the environmental aspects of Bettis operations. Waste management practices are also described.

Not Available

1992-01-01T23:59:59.000Z

266

Rydberg Atoms in Ponderomotive Potentials.  

E-Print Network (OSTI)

??In this thesis, we examine the ponderomotive interaction between an applied optical field and a highly excited Rydberg electron. An atom in a Rydberg state (more)

Knuffman, Brenton J.

2009-01-01T23:59:59.000Z

267

Absorption properties of identical atoms  

SciTech Connect

Emission rates and other optical properties of multi-particle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas. -- Highlights: The absorption rates of a pair of identical atoms in product and (anti)symmetrized states are different. The modifications of the optical properties are essentially determined by the overlapping between the atoms. The absorption properties differ, in some cases, for bosons and fermions.

Sancho, Pedro, E-mail: psanchos@aemet.es

2013-09-15T23:59:59.000Z

268

EMSL - atomic-resolution imaging  

NLE Websites -- All DOE Office Websites (Extended Search)

atomic-resolution-imaging en Molecular Hydrogen Formation from Proximal Glycol Pairs on TiO2(110). http:www.emsl.pnl.govemslwebpublicationsmolecular-hydrogen-formation-proxima...

269

Magnetism and Atomic Structure. I  

Science Journals Connector (OSTI)

3 January 1921 research-article Magnetism and Atomic Structure. I A. E. Oxley The Royal Society is collaborating with JSTOR to digitize, preserve, and extend access...

1921-01-01T23:59:59.000Z

270

Atom bouncers have it taped  

Science Journals Connector (OSTI)

... University have repeatedly bounced rubidium atoms from magnetic tape of the kind used to record audio signals1. In later experiments, they obtained better results with floppy disks.

Wayne M. Itano

1995-09-28T23:59:59.000Z

271

Similarity between positronium-atom and electron-atom scattering  

E-Print Network (OSTI)

We employ the impulse approximation for description of positronium-atom scattering. Our analysis and calculations of Ps-Kr and Ps-Ar collisions provide theoretical explanation of the similarity between the cross sections for positronium scattering and electron scattering for a range of atomic and molecular targets observed by S. J. Brawley et al. [Science 330, 789 (2010)].

Fabrikant, I I

2015-01-01T23:59:59.000Z

272

Design of Transport Casks with Depleted Uranium Gamma Shield and Advanced Safety  

NLE Websites -- All DOE Office Websites (Extended Search)

Transport Casks with Depleted Uranium Gamma Shield and Advanced Safety Transport Casks with Depleted Uranium Gamma Shield and Advanced Safety Matveev V.Z., Morenko A.I., Shapovalov V.I. Russian Federal Nuclear Center - All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) 37 Mira Prospect, Sarov, Russia, 607190, matveev@vniief.ru Maslov A.A., Orlov V.K., Semenov A.G., Sergeev V.M., Yuferov O.I., Visik A.M. Bochvar Institute of Inorganic Materials (VNIINM) 5-A Rogova street, p.b. 369, Moscow, Russia, 123060, majul2000@mail.ru Abstract - The report is dedicated to a problem of creation of a new generation of dual-purpose transport packing complete sets (TPCS) 1 with advanced safety. These sets are intended for transportation and storage of spent nuclear fuel assemblies (SNFA) 2 of VVER reactors and spent spark elements (SSE)

273

Shielding calculation techniques used in the design of fuel storage systems  

SciTech Connect

To augment the existing at-reactor fuel storage capacity, many utilities are implementing modular dry storage systems. This paper addresses the shielding design and analysis of one such storage system. Particular attention will be given to comparing various computer and hand calculation techniques. The Nutech horizontal modular storage (NUHOMS) system consists of a dry canister (a stainless steel canister containing seven pressurized water reactor fuel assemblies), a horizontal storage module (a concrete storage module), an on-site transfer cask, a trailer and cask skid, and a hydraulic ram. The shielding analyses utilized hand calculations of direct and scattered radiation, the QADMOD (three-dimensional point kernal computer program and the ANISN (one-dimensional) and DOT-IV (two-dimensional) transport theory computer programs. Each calculational technique has its advantages and disadvantages.

Wang, S.S.; Massey, J.V.

1985-11-01T23:59:59.000Z

274

Space radiation shielding analysis and dosimetry for the space shuttle program  

Science Journals Connector (OSTI)

Active and passive radiation dosimeters have been flown on every Space Shuttle mission to measure the naturally?occurring background Van Allen and galactic cosmic radiation doses that astronauts and radiation?sensitive experiments and payloads receive. A review of the various models utilized at the NASA/Johnson Space Center Radiation Analysis and Dosimetry is presented. An analytical shielding model of the Shuttle was developed as an engineering tool to aid in making premission radiation dose calculations and is discussed in detail. The anatomical man models are also discussed. A comparison between the onboard dosimeter measurements for the 24 Shuttle missions to date and the dose calculations using the radiation environment and shielding models is presented.

William Atwell; E. R. Beever; A. C. Hardy; R. G. Richmond; B. L. Cash

1989-01-01T23:59:59.000Z

275

Process for producing an aggregate suitable for inclusion into a radiation shielding product  

SciTech Connect

The present invention is directed to methods for converting depleted uranium hexafluoride to a stable depleted uranium silicide in a one-step reaction. Uranium silicide provides a stable aggregate material that can be added to concrete to increase the density of the concrete and, consequently, shield gamma radiation. As used herein, the term "uranium silicide" is defined as a compound generically having the formula U.sub.x Si.sub.y, wherein the x represents the molecules of uranium and the y represent the molecules of silicon. In accordance with the present invention, uranium hexafluoride is converted to a uranium silicide by contacting the uranium hexafluoride with a silicon-containing material at a temperature in a range between about 1450.degree. C. and about 1750.degree. C. The stable depleted uranium silicide is included as an aggregate in a radiation shielding product, such as a concrete product.

Lessing, Paul A. (Idaho Falls, ID); Kong, Peter C. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

276

Active Interrogation Observables for Enrichment Determination of DU Shielded HEU Metal Assemblies with Limited Geometrical Information  

SciTech Connect

Determining the enrichment of highly enriched uranium (HEU) metal assemblies shielded by depleted uranium (DU) proves a unique challenge to currently employed measurement techniques. Efforts to match time-correlated neutron distributions obtained through active interrogation to Monte Carlo simulations of the assemblies have shown promising results, given that the exact geometries of both the HEU metal assemblies and DU shields are known from imaging and fission site mapping. In certain situations, however, it is desirable to obtain enrichment with limited or no geometrical information of the assemblies being measured. This paper explores the possibility that the utilization of observables in the interrogation of assemblies by time-tagged D-T neutrons, including time-correlated distribution of neutrons and gammas using liquid scintillators operating on the fission chain time scale, can lead to enrichment determination without a complete set of geometrical information.

Pena, Kirsten E [ORNL] [ORNL; McConchie, Seth M [ORNL] [ORNL; Crye, Jason Michael [ORNL] [ORNL; Mihalczo, John T [ORNL] [ORNL

2011-01-01T23:59:59.000Z

277

Nuclear Rocket Test Facility Decommissioning Including Controlled Explosive Demolition of a Neutron-Activated Shield Wall  

SciTech Connect

Located in Area 25 of the Nevada Test Site, the Test Cell A Facility was used in the 1960s for the testing of nuclear rocket engines, as part of the Nuclear Rocket Development Program. The facility was decontaminated and decommissioned (D&D) in 2005 using the Streamlined Approach For Environmental Restoration (SAFER) process, under the Federal Facilities Agreement and Consent Order (FFACO). Utilities and process piping were verified void of contents, hazardous materials were removed, concrete with removable contamination decontaminated, large sections mechanically demolished, and the remaining five-foot, five-inch thick radiologically-activated reinforced concrete shield wall demolished using open-air controlled explosive demolition (CED). CED of the shield wall was closely monitored and resulted in no radiological exposure or atmospheric release.

Michael Kruzic

2007-09-01T23:59:59.000Z

278

Semi-flexible gas-insulated transmission line using electric field stress shields  

DOE Patents (OSTI)

A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements and the stress shields may also be utilized in connection with a plug and socket arrangement for providing electrical connection between main conductor sections.

Cookson, Alan H. (Churchill Borough, PA); Dale, Steinar J. (Monroeville, PA); Bolin, Philip C. (Wilkins Township, Allegheny County, PA)

1982-12-28T23:59:59.000Z

279

Shielded coherent synchrotron radiation and its possible effect in the next linear collider  

SciTech Connect

Shielded coherent synchrotron radiation is discussed in two cases: (1) a beam following a curved path in a plane midway between two parallel, perfectly conducting plates, and (2) a beam circulating in a toroidal chamber with resistive walls. Wake fields and the radiated energy are computed with parameters for the high-energy bunch compressor of the Next Linear Collider. 5 refs., 4 figs., 1 tab.

Warnock, R.L.

1991-05-01T23:59:59.000Z

280

IDS120h GEOMETRY WITH SHIELDING VESSELS ENERGY FLOW ANALYSIS CONTINUED  

E-Print Network (OSTI)

AREAS Np = 100,000 AND 500,000 EVENTS Np = 100,000 (1) Np = 500,000 (2) (1) SH#1-4: 1684.27 kW --> 1603/g PEAK VALUE FOR 8-10 cm LENGTH JUST AFTER BP1 SECTION, BUT IT IS ISOLATED ONLY ALONG -x AXIS REGION BEADS/He SHIELDING. 9 BP1 (~50 cm), BP2 (~10 cm) Be SECTIONS WORK STILL IN PROGRESS. #12;

McDonald, Kirk

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

EMI shield enhancement through the addition of copper coated glass fibers  

E-Print Network (OSTI)

E. , University of Wisconsin-Madison Chair of Committee: Dr. G. W. Halldin This research investigated the feasibility of using copper coated glass fibers to increase the EMI shielding characteristics of vinyl ester thermosetting resin. The fibers were coated... 35 36 37 41 41 48 55 57 58 58 58 58 60 61 62 62 62 Plate Times. Surface Area Analysis Scanning Electron Microscopy. MOLDED COMPOSITE MATERIALS. Resin. Sample Preparation. Evaluation. Scanning Electron Microscopy Flexural...

Montanye, Jeffrey Richard

1988-01-01T23:59:59.000Z

282

The Atomic City / The Magic of the Atom - 1950's Atomic Energy Commission Documentary  

SciTech Connect

The story of American cities located near atomic power plants, and steps taken monitoring radiation to ensure the safety of the public who live nearby. .

None

2012-06-04T23:59:59.000Z

283

Castor-1C spent fuel storage cask decay heat, heat transfer, and shielding analyses  

SciTech Connect

This report documents the decay heat, heat transfer, and shielding analyses of the Gesellschaft fuer Nuklear Services (GNS) CASTOR-1C cask used in a spent fuel storage demonstration performed at Preussen Elektra's Wurgassen nuclear power plant. The demonstration was performed between March 1982 and January 1984, and resulted in cask and fuel temperature data and cask exterior surface gamma-ray and neutron radiation dose rate measurements. The purpose of the analyses reported here was to evaluate decay heat, heat transfer, and shielding computer codes. The analyses consisted of (1) performing pre-look predictions (predictions performed before the analysts were provided the test data), (2) comparing ORIGEN2 (decay heat), COBRA-SFS and HYDRA (heat transfer), and QAD and DOT (shielding) results to data, and (3) performing post-test analyses if appropriate. Even though two heat transfer codes were used to predict CASTOR-1C cask test data, no attempt was made to compare the two codes. The codes are being evaluated with other test data (single-assembly data and other cask data), and to compare the codes based on one set of data may be premature and lead to erroneous conclusions.

Rector, D.R.; McCann, R.A.; Jenquin, U.P.; Heeb, C.M.; Creer, J.M.; Wheeler, C.L.

1986-12-01T23:59:59.000Z

284

A shielded storage and processing facility for radioisotope thermoelectric generator heat source production  

SciTech Connect

A shielded storage rack has been installed as part of the Radioisotope Power Systems Facility (RPSF) at the U.S. Department of Energy's (DOE) Hanford Site in Washington State. The RPSF is designed to replace an existing facility at DOE's Mound Site near Dayton, Ohio, where General Purpose Heat Source (GPHS) modules are currently assembled and installed into Radioisotope Thermoelectric Generators (RTG). The overall design goal of the RPSF is to increase annual production throughput, while at the same time reducing annual radiation exposure to personnel. The shield rack design successfully achieved this goal for the Module Reduction and Monitoring Facility (MRMF), which processes and stores assembled GPHS modules, prior to their installation into RTGs. The shield rack design is simple and effective, with the result that background radiation levels within Hanford's MRMF room are calculated at just over three percent of those typically experienced during operation of the existing MRMF at Mound, despite the fact that Hanford's calculations assume five times the GPHS inventory of that assumed for Mound.

Sherrell, D.L. (Westinghouse Hanford Company, P.O. Box 1970, Mail Stop N1-42, Richland, Washington 99352 (United States))

1993-01-15T23:59:59.000Z

285

Shielding Studies for the CERN Super-Proton-Synchrotron at Experimental Point 5  

E-Print Network (OSTI)

The European Laboratory for Particle Research, CERN has been operated the Super Proton Sychrotron (SPS) for more than 30 years with the shielding design knowledge of the early 70s. At that time particle transport codes were neither available nor capable of dealing with deep lateral shielding calculations. For the future LHC increasing projected values of beam intensity in the SPS and decreasing limits to radiation exposure have led to the need to re-assess the shielding at point 5 of the SPS. 20 years ago this area housed the UA1 experiment of Carlo Rubbia (nobel-price 1984). The thesis describes a re-assessment based on simulations using the multi-purpose radiation transport codes FLUKA and MCNPX. The latter one was utilized for geometry design and to compare variance reduction methods. Different assumed beam-loss points along the beam-line together with fluence-to-doserate conversion calculations were used to find the worst case scenario. Dose-rates as well as particle-energy spectra inside the accessible a...

Mller, Mario J

2004-01-01T23:59:59.000Z

286

A shielded storage and processing facility for radioisotope thermoelectric generator heat source production  

SciTech Connect

This report discusses a shielded storage rack which has been installed as part of the Radioisotope Power Systems Facility (RPSF) at the US Department of Energy's (DOE) Hanford Site in Washington State. The RPSF is designed to replace an existing facility at DOE's Mound Site near Dayton, Ohio, where General Purpose Heat Source (GPHS) modules are currently assembled and installed into Radioisotope Thermoelectric Generators (RTG). The overall design goal of the RPSF is to increase annual production throughput, while at the same time reducing annual radiation exposure to personnel. The shield rack design successfully achieved this goal for the Module Reduction and Monitoring Facility (MRMF), which process and stores assembled GPHS modules, prior to their installation into RTGS. The shield rack design is simple and effective, with the result that background radiation levels within Hanford's MRMF room are calculated at just over three percent of those typically experienced during operation of the existing MRMF at Mound, despite the fact that Hanford's calculations assume five times the GPHS inventory of that assumed for Mound.

Sherrell, D.L.

1992-06-01T23:59:59.000Z

287

A shielded storage and processing facility for radioisotope thermoelectric generator heat source production  

SciTech Connect

This report discusses a shielded storage rack which has been installed as part of the Radioisotope Power Systems Facility (RPSF) at the US Department of Energy`s (DOE) Hanford Site in Washington State. The RPSF is designed to replace an existing facility at DOE`s Mound Site near Dayton, Ohio, where General Purpose Heat Source (GPHS) modules are currently assembled and installed into Radioisotope Thermoelectric Generators (RTG). The overall design goal of the RPSF is to increase annual production throughput, while at the same time reducing annual radiation exposure to personnel. The shield rack design successfully achieved this goal for the Module Reduction and Monitoring Facility (MRMF), which process and stores assembled GPHS modules, prior to their installation into RTGS. The shield rack design is simple and effective, with the result that background radiation levels within Hanford`s MRMF room are calculated at just over three percent of those typically experienced during operation of the existing MRMF at Mound, despite the fact that Hanford`s calculations assume five times the GPHS inventory of that assumed for Mound.

Sherrell, D.L.

1992-06-01T23:59:59.000Z

288

SHIELDING AND DETECTOR RESPONSE CALCULATIONS PERTAINING TO CATEGORY 1 QUANTITIES OF PLUTONIUM AND HAND-HELD PLASTIC SCINTILLATORS  

SciTech Connect

Nuclear facilities sometimes use hand-held plastic scintillator detectors to detect attempts to divert special nuclear material in situations where portal monitors are impractical. MCNP calculations have been performed to determine the neutron and gamma radiation field arising from a Category I quantity of weapons-grade plutonium in various shielding configurations. The shields considered were composed of combinations of lead and high-density polyethylene such that the mass of the plutonium plus shield was 22.7 kilograms. Monte-Carlo techniques were also used to determine the detector response to each of the shielding configurations. The detector response calculations were verified using field measurements of high-, medium-, and low- energy gamma-ray sources as well as a Cf-252 neutron source.

Couture, A.

2013-06-07T23:59:59.000Z

289

E-Print Network 3.0 - atomization atomic absorption Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

atomic absorption Search Powered by Explorit Topic List Advanced Search Sample search results for: atomization atomic absorption Page: << < 1 2 3 4 5 > >> 1 :coherently trapped in...

290

Bogoliubov theory and bosonic atoms  

E-Print Network (OSTI)

We formulate the Bogoliubov variational principle in a mathematical framework similar to the generalized Hartree-Fock theory. Then we analyze the Bogoliubov theory for bosonic atoms in details. We discuss heuristically why the Bogoliubov energy should give the first correction to the leading energy of large bosonic atoms.

Phan Thanh Nam

2011-09-13T23:59:59.000Z

291

Heating rates in collisionally opaque alkali-metal atom traps: Role of secondary collisions  

Science Journals Connector (OSTI)

Grazing collisions with background gas are the major cause of trap loss and trap heating in atom traps. To first order, these effects do not depend on the trap density. In collisionally opaque trapped atom clouds, however, scattered atoms with an energy E larger than the effective trap depth Eeff, which are destined to escape from the atom cloud, will have a finite probability for a secondary collision. This results in a contribution to the heating rate that depends on the column density ?nl? of the trapped atoms, i.e., the product of density and characteristic size of the trap. For alkali-metal atom traps, secondary collisions are quite important due to the strong long-range interaction with like atoms. We derive a simple analytical expression for the secondary heating rate, showing a dependency proportional to ?nl??Eeff1/2. When extrapolating to a vanishing column density, only primary collisions with the background gas will contribute to the heating rate. This contribution is rather small, due to the weak long-range interaction of the usual background gas species in an ultrahigh-vacuum systemHe, Ne, or Arwith the trapped alkali-metal atoms. We conclude that the transition between trap-loss collisions and heating collisions is determined by a cutoff energy 200??K<~Eeff<~400??K, much smaller than the actual trap depth E in most magnetic traps. Atoms with an energy Eeffatoms Li through Cs as a function of the effective trap depth, the column density of the trap, and the species in the background gas. The predictions of our model are in good agreement with the experimental data of Myatt for heating rates in high-density 87Rb-atom magnetic traps at JILA, including the effect of the rf shield and the composition of the background gas. It is shown that collisions with atoms from the Oort cloud also contribute to the heating rate. For 85Rb the calculated heating rate is below the experimentally observed value at JILA, supporting the idea that inelastic collisions in the trap are the major source of heating.

H. C. W. Beijerinck

2000-11-15T23:59:59.000Z

292

Atomic, Molecular & Optical Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic, Molecular and Optical Sciences Atomic, Molecular and Optical Sciences The goal of the program is to understand the structure and dynamics of atoms and molecules using photons and ions as probes. The current program is focussed on studying inner-shell photo-ionization and photo-excitation of atoms and molecules, molecular orientation effects in slow collisions, slowing and cooling molecules, and X-ray photo-excitation of laser-dressed atoms. The experimental and theoretical efforts are designed to break new ground and to provide basic knowledge that is central to the programmatic goals of the Department of Energy (DOE). Unique LBNL facilities such as the Advanced Light Source (ALS), the ECR ion sources at the 88-inch cyclotron, and the National Energy Research Scientific Computing Center (NERSC) are

293

Spectral Emission of Moving Atom  

E-Print Network (OSTI)

A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

J. X. Zheng-Johansson

2008-03-17T23:59:59.000Z

294

Manhattan Project: Adventures Inside the Atom  

Office of Scientific and Technical Information (OSTI)

ADVENTURES INSIDE THE ATOM ADVENTURES INSIDE THE ATOM General Electric, National Archives (1948) Resources > Library Below is Adventures Inside the Atom, a comic book history of nuclear energy that was produced in 1948 by the General Electric Company. Scroll down to view the full-size images of each page. This publication was produced at the request of the the Assistant Manager for Public Education, Oak Ridge Operations Office, Atomic Energy Commission. It is reproduced here via the National Archives. Adventures Inside the Atom, p. 1 Adventures Inside the Atom, p. 2 Adventures Inside the Atom, p. 3 Adventures Inside the Atom, p. 4 Adventures Inside the Atom, p. 5 Adventures Inside the Atom, p. 6 Adventures Inside the Atom, p. 7 Adventures Inside the Atom, p. 8 Adventures Inside the Atom, p. 9

295

Development of a bellows chamber with a comb-type RF shield for high-current accelerators  

Science Journals Connector (OSTI)

An all-metal bellows chamber with a comb-type Radio Frequency (RF) shield for a high-current accelerator was developed and tested at the KEK B-factory (KEKB). The comb-type RF shield has no thin fingers but has nested comb teeth instead at an inner surface. The comb-type RF-shield has a higher thermal strength structurally compared to the conventional finger-type one. Leakage of the TE mode like HOM through the RF shield is almost suppressed. Two test models of bellows chambers installed in the 3.5GeV positron ring of KEKB showed good properties up to a stored beam current of 1.5A. The temperature rise of the corrugation was about 7C and the temperature rise was about 16 of that of the bellows chamber with a conventional finger-type RF shield located under the same condition. The temperature rise of the comb teeth was about 22C, while that of fingers of the finger-type RF shield was estimated to be about 105C for the equivalent HOM power. No vacuum arcing was detected during beam operation.

Y. Suetsugu; M. Shirai; K. Shibata; K. Murata; M. Kaneko; K. Sakamoto; K. Sugisaki; M. Kawahara

2004-01-01T23:59:59.000Z

296

AtomicNuclear Properties  

NLE Websites -- All DOE Office Websites (Extended Search)

HTML_PAGES HTML_PAGES This AtomicNuclearProperties page is under intermittent development. Suggestions and comments are welcome. Please report errors. Chemical elements: For entries in red, a pull-down menu permits selection of the physical state. Cryogenic liquid densties are at the boiling point at 1 atm. 0n 1Ps 1H 2He 3Li 4Be 5B 6C 7N 8O 9F 10Ne 11Na 12Mg 13Al 14Si 15P 16S 17Cl 18Ar 19K 20Ca 21Sc 22Ti 23V 24Cr 25Mn 26Fe 27Co 28Ni 29Cu 30Zn 31Ga 32Ge 33As 34Se 35Br 36Kr 37Rb 38Sr 39Y 40Zr 41Nb 42Mo 43Tc 44Ru 45Rh 46Pd 47Ag 48Cd 49In 50Sn 51Sb 52Te 53I 54Xe 55Cs 56Ba 57La 72Hf 73Ta 74W 75Re 76Os 77Ir 78Pt 79Au 80Hg 81Tl 82Pb 83Bi 84Po 85At 86Rn 87Fr 88Ra 89Ac 104Rf 105Db 106Sg 107Bh 108Hs 109Mt 110Ds 111Rg 112 113 114 115 116 mt 118

297

In-situ control system for atomization  

DOE Patents (OSTI)

Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray.

Anderson, Iver E. (Ames, IA); Figliola, Richard S. (Central, SC); Terpstra, Robert L. (Ames, IA)

1995-06-13T23:59:59.000Z

298

Summary of Disposable Debris Shields (DDS) Analysis for Development of Solid Debris Collection at NIF  

SciTech Connect

Collection of solid debris from the National Ignition Facility (NIF) is being developed both as a diagnostic tool and as a means for measuring nuclear reaction cross sections relevant to the Stockpile Stewardship Program and nuclear astrophysics. The concept is straightforward; following a NIF shot, the debris that is produced as a result of the capsule and hohlraum explosion would be collected and subsequently extracted from the chamber. The number of nuclear activations that occurred in the capsule would then be measured through a combination of radiation detection and radiochemical processing followed by mass spectrometry. Development of the catcher is challenging due to the complex environment of the NIF target chamber. The collector surface is first exposed to a large photon flux, followed by the debris wind that is produced. The material used in the catcher must be mechanically strong in order to withstand the large amount of energy it is exposed to, as well as be chemically compatible with the form and composition of the debris. In addition, the location of the catcher is equally important. If it is positioned too close to the center of the target chamber, it will be significantly ablated, which could interfere with the ability of the debris to reach the surface and stick. If it is too far away, the fraction of the debris cloud collected will be too small to result in a statistically significant measurement. Material, geometric configuration, and location must all be tested in order to design the optimal debris collection system for NIF. One of the first ideas regarding solid debris collection at NIF was to use the disposable debris shields (DDS), which are fielded over the final optics assemblies (FOA) 7 m away from the center of the target chamber. The DDS are meant to be replaced after a certain number of shots, and if the shields could be subsequently analyzed after removal, it would serve as a mechanism for fielding a relatively large collection area through the use of a part meant to be replaced regularly. The solid angle covered by one of the shields is roughly 10{sup -4} of 4{pi}. If several shields were analyzed at once, it would increase the solid angle of the collection area accordingly. The glass shields consist of ammonia hardened silica with a sol gel coating and kapton tape around the edge. The square sheets are 14-inch on each side. The original shields were 1 mm thick, but it was determined that a thicker shield (3.3 mm) was more effective in preventing debris from reaching the FOA. The Solid Radchem group received two sets of DDS as part of our evaluation of the potential use of the DDS as solid debris collectors. The first set consisted of two 3.3 mm shields, one each from the top and bottom of the chamber (the '3mm set'). The second set consisted of four 1mm shields, one from the top of the chamber and the other three from the bottom (the 'IFSA set'). For each set, the shields were cut into smaller subsamples, which were then imaged using scanning electron microscopy (SEM) followed by chemical leaching and mass spectrometry. The purpose was to evaluate both the quantity and identity of the debris that was present on the DDS surfaces, and to determine if any of the capsule debris was reaching the chamber walls. In addition, potential enhancement due to gravity in the chamber was evaluated by directly comparing shields fielded in the top and bottom of the chamber. Based on the results, the use of the DDS as debris collectors would be evaluated. The results from both sets were presented to the DDS Working Group. The slides are attached to this document. The 3mm set results are presented first, followed by the results from the IFSA set. In both cases it was determined that a small fraction of the overall debris field was collected on the DDS. This means that the debris that is formed during a NIF shot is condensing out of the plasma and depositing on surfaces closer to the target chamber center, or else it is simply falling to the bottom of the chamber. In either case, it was determined that using

Shaughnessy, D A; Moody, K J; Grant, P M; Lewis, L A; Hutcheon, I D; Lindvall, R; Gostic, J M

2011-11-20T23:59:59.000Z

299

Supersonic coal water slurry fuel atomizer  

DOE Patents (OSTI)

A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities.

Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA); Balsavich, John (Foxborough, MA)

1991-01-01T23:59:59.000Z

300

Questions and Answers - Does an atom smasher really smash atoms?  

NLE Websites -- All DOE Office Websites (Extended Search)

is an accelerator? is an accelerator? Previous Question (What is an accelerator?) Questions and Answers Main Index Next Question (Where and how do you get your electrons for your accelerator?) Where and how do you get yourelectrons for your accelerator? Does an atom smasher really smash atoms? Well, yes, they do, but we now prefer to call them by their less aggression-centered name, "particle harmony disrupters." Of course some atom smashers do much more smashing than others. We use electrons in our accelerator to study the nucleus of an atom. Remember that electrons are negative, as are the electrons surrounding the target. Since like charged particles repel each other, our particles have to have enough energy to blast through that electron cloud to get to the nucleus. The electrons then

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Radiation physics and shielding codes and analyses applied to design-assist and safety analyses of CANDU{sup R} and ACR{sup TM} reactors  

SciTech Connect

This paper discusses the radiation physics and shielding codes and analyses applied in the design of CANDU and ACR reactors. The focus is on the types of analyses undertaken rather than the inputs supplied to the engineering disciplines. Nevertheless, the discussion does show how these analyses contribute to the engineering design. Analyses in radiation physics and shielding can be categorized as either design-assist or safety and licensing (accident) analyses. Many of the analyses undertaken are designated 'design-assist' where the analyses are used to generate recommendations that directly influence plant design. These recommendations are directed at mitigating or reducing the radiation hazard of the nuclear power plant with engineered systems and components. Thus the analyses serve a primary safety function by ensuring the plant can be operated with acceptable radiation hazards to the workers and public. In addition to this role of design assist, radiation physics and shielding codes are also deployed in safety and licensing assessments of the consequences of radioactive releases of gaseous and liquid effluents during normal operation and gaseous effluents following accidents. In the latter category, the final consequences of accident sequences, expressed in terms of radiation dose to members of the public, and inputs to accident analysis, e.g., decay heat in fuel following a loss-of-coolant accident, are also calculated. Another role of the analyses is to demonstrate that the design of the plant satisfies the principle of ALARA (as low as reasonably achievable) radiation doses. This principle is applied throughout the design process to minimize worker and public doses. The principle of ALARA is an inherent part of all design-assist recommendations and safety and licensing assessments. The main focus of an ALARA exercise at the design stage is to minimize the radiation hazards at the source. This exploits material selection and impurity specifications and relies heavily on experience and engineering judgement, consistent with the ALARA philosophy. Special care is taken to ensure that the best estimate dose rates are used to the extent possible when applying ALARA. Provisions for safeguards equipment are made throughout the fuel-handling route in CANDU and ACR reactors. For example, the fuel bundle counters rely on the decay gammas from the fission products in spent-fuel bundles to record the number of fuel movements. The International Atomic Energy Agency (IAEA) Safeguards system for CANDU and ACR reactors is based on item (fuel bundle) accounting. It involves a combination of IAEA inspection with containment and surveillance, and continuous unattended monitoring. The spent fuel bundle counter monitors spent fuel bundles as they are transferred from the fuelling machine to the spent fuel bay. The shielding and dose-rate analysis need to be carried out so that the bundle counter functions properly. This paper includes two codes used in criticality safety analyses. Criticality safety is a unique phenomenon and codes that address criticality issues will demand specific validations. However, it is recognised that some of the codes used in radiation physics will also be used in criticality safety assessments. (authors)

Aydogdu, K.; Boss, C. R. [Atomic Energy of Canada Limited, Sheridan Science and Technology Park, Mississauga, Ont. L5K 1B2 (Canada)

2006-07-01T23:59:59.000Z

302

Atoms 2014, 2, 378-381; doi:10.3390/atoms2030378 OPEN ACCESS  

E-Print Network (OSTI)

Atoms 2014, 2, 378-381; doi:10.3390/atoms2030378 OPEN ACCESS atomsISSN 2218-2004 www.mdpi.com/journal/atoms.calisti@univ-amu.fr 3 International Atomic Energy Agency, Atomic and Molecular Data Unit, Nuclear Data Section, P.O. Box for the first two SLSP workshops are for simple atomic systems: the hydrogen atom or hydrogen-like one

303

Chemical factors influencing selenium atomization  

E-Print Network (OSTI)

Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

Buren, Mary Sue

2012-06-07T23:59:59.000Z

304

THE INTERACTION OF RARE GAS METASTABLE ATOMS  

E-Print Network (OSTI)

in the study of metastable atom reactions. > 1 it- Fig, laa raetastable rare gas atom, three quantities are necessaryOF iiARE GAS METASTABLF ATOMS Andrew Zun-Foh Wang M a t e r

Wang, A.Z.-F.

2011-01-01T23:59:59.000Z

305

Imaging atoms in 3-D  

ScienceCinema (OSTI)

Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

Ercius, Peter

2014-06-27T23:59:59.000Z

306

ATOMIC ENERGY ACT OF 1946  

NLE Websites -- All DOE Office Websites (Extended Search)

ect of the us0 of atomic energy for civilian purposes upon the social, economic, and political structures of today cannot now bo determined. It is a field in which unknown factors...

307

Quantum information with Rydberg atoms  

Science Journals Connector (OSTI)

Rydberg atoms with principal quantum number n?1 have exaggerated atomic properties including dipole-dipole interactions that scale as n4 and radiative lifetimes that scale as n3. It was proposed a decade ago to take advantage of these properties to implement quantum gates between neutral atom qubits. The availability of a strong long-range interaction that can be coherently turned on and off is an enabling resource for a wide range of quantum information tasks stretching far beyond the original gate proposal. Rydberg enabled capabilities include long-range two-qubit gates, collective encoding of multiqubit registers, implementation of robust light-atom quantum interfaces, and the potential for simulating quantum many-body physics. The advances of the last decade are reviewed, covering both theoretical and experimental aspects of Rydberg-mediated quantum information processing.

M. Saffman; T. G. Walker; K. Mlmer

2010-08-18T23:59:59.000Z

308

Absorption properties of identical atoms  

E-Print Network (OSTI)

Emission rates and other optical properties of multiparticle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas.

Pedro Sancho

2013-07-31T23:59:59.000Z

309

Neutron source in the MCNPX shielding calculating for electron accelerator driven facility  

SciTech Connect

Argonne National Laboratory (ANL) of USA and Kharkov Inst. of Physics and Technology (KIPT) of Ukraine have been collaborating on the design development of an experimental neutron source facility. It is an accelerator driven system (ADS) utilizing a subcritical assembly driven by electron accelerator. The facility will be utilized for performing basic and applied nuclear researches, producing medical isotopes, and training young nuclear specialists. Monte Carlo code MCNPX has been utilized as a design tool due to its capability to transport electrons, photons, and neutrons at high energies. However the facility shielding calculations with MCNPX need enormous computational resources and the small neutron yield per electron makes sampling difficulty for the Monte Carlo calculations. A method, based on generating and utilizing neutron source file, was proposed and tested. This method reduces significantly the required computer resources and improves the statistics of the calculated neutron dose outside the shield boundary. However the statistical errors introduced by generating the neutron source were not directly represented in the results, questioning the validity of this methodology, because an insufficiently sampled neutron source can cause error on the calculated neutron dose. This paper presents a procedure for the validation of the generated neutron source file. The impact of neutron source statistic on the neutron dose is examined by calculating the neutron dose as a function of the number of electron particles used for generating the neutron source files. When the value of the calculated neutron dose converges, it means the neutron source has scored sufficient records and statistic does not have apparent impact on the calculated neutron dose. In this way, the validity of neutron source and the shield analyses could be verified. (authors)

Zhong, Z.; Gohar, Y. [Nuclear Engineering Div., Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2012-07-01T23:59:59.000Z

310

Shielding requirements for the transport of nuclear warhead components under decommissioning  

SciTech Connect

The requirements to carry out accurate shielding calculations involved with the safe off-site transportation of packages containing nuclear warhead components, special assemblies and radioactive materials are discussed. The need for (a) detailed information on the geometry and material composition of the packaging and radioactive load, (b) accurate representation of the differential energy spectra (dN/dE) for the neutron and gamma spectra emitted by the radioactive materials enclosed in the packaging, (c) well-tested neutron and photon cross section libraries, (d) and accurate three-dimensional Monte Carlo transport codes are illustrated. A brief discussion of the need for reliable dose measurements is presented.

Hansen, L.F.

1994-09-01T23:59:59.000Z

311

Dose measurements behind reduced shielding at the Texas A&M University variable energy cyclotron  

E-Print Network (OSTI)

, the relative count rates of the detectors after irradiation can be used to estimate the spectral dis- tribution of the neutron field, while the absolute activity of the detector is a measure of exposure (Ce69). This technique is useful in measuring neutron... be measured simultaneously in high flux areas in the vault and in low flux areas outside the reduced shielding. The detector normally utilized in the spherical remmeter is a lithium iodide, europium activated (LiI(Eu)) scintillation type thermal neutron...

Kay, Douglas Carey

2012-06-07T23:59:59.000Z

312

Advantages of the shielded containers at the Waste Isolation Pilot Plant.  

SciTech Connect

The Waste Isolation Pilot Plant (WIPP) disposal operations currently employ two different disposal methods: one for Contact Handled (CH) waste and another for Remote Handled (RH) waste. CH waste is emplaced in a variety of payload container configurations on the floor of each disposal room. In contrast, RH waste is packaged into a single type of canister and emplaced in pre-drilled holes in the walls of disposal rooms. Emplacement of the RH waste in the walls must proceed in advance of CH waste emplacement and therefore poses logistical constraints, in addition to the loss of valuable disposal capacity. To improve operational efficiency and disposal capacity, the Department of Energy (DOE) has proposed a shielded container for certain RH waste streams. RH waste with relatively low gammaemitting activity would be packaged in lead-lined containers, shipped to WIPP in existing certified transportation packages for CH waste and emplaced in WIPP among the stacks of CH waste containers on the floor of a disposal room. RH waste with high gamma-emitting activity would continue to be emplaced in the boreholes along the walls. The new RH container is similar to the nominal 208-liter (55-gallon) drum, however it includes about 2.5 cm (1 in) of lead, sandwiched between thick steel sheets. Furthermore, the top and bottom are made of thick plate steel to strengthening the package to meet transportation requirements. This robust configuration provides an overpack for materials that otherwise would be RH waste. This paper describes the container and the regulatory approach used to meet the requirements imposed by regulations that apply to WIPP. This includes a Performance Assessment used to evaluate WIPP's long-term performance and the DOE's approach to gain approval for the transportation of shielded containers. This paper also describes estimates of the DOE's RH transuranic waste inventory that may be packaged and emplaced in shielded containers. Finally, the paper includes a discussion of how the DOE proposes to track the waste packaged into shielded containers against the RH waste inventory and how this will comply with the regulated volume.

Nelson, Roger A. (U.S. Department of Energy, Carlsbad, NM); Dunagan, Sean C.

2010-05-01T23:59:59.000Z

313

Magnetic shielding properties of plasma sprayed YBa2Cu3O7-x on nickel substrates  

Science Journals Connector (OSTI)

YBa2Cu3O7-x films were grown by a low pressure plasma spraying technique and atmospheric plasma spray on polycrystalline nickel substrate using yttrium-stabilized zirconia as a buffer layer. After post-annealing in oxygen at high temperature, zero resistance is reached above 77 K. YBa2Cu3O7-x films with thicknesses between 120 and 420 ?m were prepared and their critical currents measured. The a.c. magnetic shielding properties were determined in the high frequency region, 100 kHz to 3 MHz. The relations between the screening properties, the critical currents and the microstructure of the thin films are discussed.

D. Castello; J. Fontcuberta; M. Pont; J.S. Muoz

1992-01-01T23:59:59.000Z

314

The Conceptional Design of the Shielding Layout and Beam Absorber at the PXIE  

SciTech Connect

Project X is a high intensity proton facility conceived to support a world-leading physics program at Fermilab. Project X will provide high intensity beams for neutrino, kaon, muon, and nuclei based experiments and for studies supporting energy applications. The Project X Injector Experiment (PIXIE) is a prototype of the Project X front end. A 30 MeV 50 kW beam will be used to validate the design concept of the Project X. This paper discusses a design of the accelerator enclosure radiation shielding and the beam dump.

Eidelman, Yu.; Kerby, J.; Lebedev, V.; Leibfritz, J.; Leveling, T.; Nagaisev, S.; Stanek, R.; /Fermilab

2012-05-14T23:59:59.000Z

315

A robust and well shielded thermal conductivity device for low temperature measurements  

SciTech Connect

We present a compact mechanically robust thermal conductivity measurement apparatus for measurements at low temperatures (<1 K) and high magnetic fields on small high-purity single crystal samples. A high-conductivity copper box is used to enclose the sample and all the components. The box provides protection for the thermometers, heater, and most importantly the sample increasing the portability of the mount. In addition to physical protection, the copper box is also effective at shielding radio frequency electromagnetic interference and thermal radiation, which is essential for low temperature measurements. A printed circuit board in conjunction with a braided ribbon cable is used to organize the delicate wiring and provide mechanical robustness.

Toews, W. H.; Hill, R. W. [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

2014-04-15T23:59:59.000Z

316

Self-shielding of a plasma-exposed surface during extreme transient heat loads  

SciTech Connect

The power deposition on a tungsten surface exposed to combined pulsed/continuous high power plasma is studied. A study of the correlation between the plasma parameters and the power deposition on the surface demonstrates the effect of particle recycling in the strongly coupled regime. Upon increasing the input power to the plasma source, the energy density to the target first increases then decreases. We suggest that the sudden outgassing of hydrogen particles from the target and their subsequent ionization causes this. This back-flow of neutrals impedes the power transfer to the target, providing a shielding of the metal surface from the intense plasma flux.

Zielinski, J. J.; Meiden, H. J. van der; Morgan, T. W.; Hoen, M. H. J. 't; De Temmerman, G., E-mail: g.c.detemmerman@differ.nl [FOM Institute DIFFER, Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Schram, D. C. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2014-03-24T23:59:59.000Z

317

Demonstration of shield-type longwall supports at York Canyon Mine of Kaiser Steel Corporation. Final technical report A  

SciTech Connect

This report represents work on a program that was originated by the USBM of the Department of the Interior and was transferred to the Department of Energy on October 1, 1977. A demonstration with the Government funded Hemscheidt 320 HSL caliper type shield supports was conducted at three longwall panels of Kaiser Steel Corporation's York Canyon Mine. The purpose of this longwall demonstration was to provide the US coal industry with information on all aspects of shield longwall mining in high seams. The demonstration provided a working model for the coal industry and during the project, 350 people from the industry, schools, and government agencies visited the demonstration. They were provided with a first hand knowledge of a working shield longwall. The demonstration showed that the control of large coal lumps may be a problem in the mining of coal seam thicker than 8 feet. Mining with shield type supports provided good working conditions and a safe working environment. The shield requires very little maintenance and has a high mechanical availability.

Lawrence, R.G.; King, R.

1980-04-01T23:59:59.000Z

318

Selfish atom selects quantum resonances at fractional atomic frequencies  

E-Print Network (OSTI)

We show that the atom as a "quantum entity", driven by an external field in the form of pulse sequence at repetition rate equal to the internal quantum frequency divided by an integer n, responds resonantly. It seeks and finds its characteristic frequencies in any possible combination of its frequencies. This is an indication of self expression by the atom at many sub-frequencies of its own transition frequencies. It is a non-intuitive phenomenon since the external repetition rate has no quantum character, yet the atom responds to it if the rate is equal to 1/n its eigen-frequency. We believe that our results will have implications in other quantum related processes, such as resonant enhancement of chemical reactions and biological processes.

Gennady A. Koganov; Reuben Shuker

2014-09-17T23:59:59.000Z

319

Comparison Of Hybrid Methods For Global Variance Reduction In Shielding Calculations  

SciTech Connect

For Monte Carlo shielding problems that calculate a mesh tally over the entire problem, the relative uncertainties computed for each voxel can vary widely. This can lead to unacceptably long run times in order to reduce the uncertainties in all areas of the problem to a reasonably low level. Hybrid methods using estimates from deterministic calculations to create importance maps for variance reduction in Monte Carlo calculations have been successfully used to optimize the calculation of specific tallies. For the global problem, several methods have been proposed that create importance maps that distribute Monte Carlo particles in such a way as to achieve a more uniform distribution of relative uncertainty across the problem. The goal is to compute a mesh tally with nearly the same relative uncertainties in the low flux/dose areas as in the high flux/dose areas. Methods based on only forward deterministic estimates and methods using both forward and adjoint deterministic methods have been implemented the SCALE/MAVRIC package and have been compared against each other by computing global mesh tallies on several representative shielding problems. Methods using both forward and adjoint estimates provide better performance for computing more uniform relative uncertainties across a global mesh tally.

Peplow, Douglas E. [ORNL

2013-01-01T23:59:59.000Z

320

Collection of atomic mercury by electrostatic precipitators  

Science Journals Connector (OSTI)

... Flameless atomic absorption spectroscopy was used to measure the difference in the mercury concentration of gas ...

O. M. G. NEWMAN; D. J. PALMER

1978-10-12T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
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321

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium  

E-Print Network (OSTI)

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium by Sarah B. Nagel A Thesis Submitted Houston, Texas February, 2008 #12;Abstract Ultracold Collisions in Atomic Strontium by Sarah B. Nagel In this work with atomic Strontium, the atoms are first laser cooled and subse- quently trapped, in a MOT

Killian, Thomas C.

322

Atomic Cascade in Muonic and Hadronic Hydrogen Atoms  

E-Print Network (OSTI)

The atomic cascade in $\\mu^- p$ and $\\pi^- p$ atoms has been studied with the improved version of the extended cascade model in which new quantum mechanical calculations of the differential and integral cross sections of the elastic scattering, Stark transitions and Coulomb de-excitation have been included for the principal quantum number values $n\\le 8$ and the relative energies $E \\ge 0.01$ eV. The $X$-ray yields and kinetic energy distributions are compared with the experimental data.

T. S. Jensen; V. P. Popov; V. N. Pomerantsev

2007-12-18T23:59:59.000Z

323

Observation of relativistic antihydrogen atoms  

SciTech Connect

An observation of relativistic antihydrogen atoms is reported in this dissertation. Experiment 862 at Fermi National Accelerator Laboratory observed antihydrogen atoms produced by the interaction of a circulating beam of high momentum (3 < p < 9 GeV/c) antiprotons and a jet of molecular hydrogen gas. Since the neutral antihydrogen does not bend in the antiproton source magnets, the detectors could be located far from the interaction point on a beamline tangent to the storage ring. The detection of the antihydrogen is accomplished by ionizing the atoms far from the interaction point. The positron is deflected by a magnetic spectrometer and detected, as are the back to back photons resulting from its annihilation. The antiproton travels a distance long enough for its momentum and time of flight to be measured accurately. A statistically significant sample of 101 antihydrogen atoms has been observed. A measurement of the cross section for {bar H}{sup 0} production is outlined within. The cross section corresponds to the process where a high momentum antiproton causes e{sup +} e{sup -} pair creation near a nucleus with the e{sup +} being captured by the antiproton. Antihydrogen is the first atom made exclusively of antimatter to be detected. The observation experiment's results are the first step towards an antihydrogen spectroscopy experiment which would measure the n = 2 Lamb shift and fine structure.

Blanford, Glenn DelFosse

1998-01-01T23:59:59.000Z

324

Design of an active shield dipole magnet in the interaction region of the KEK B-Factory  

SciTech Connect

Due to their detrimental effect on the experimental detector of the KEK B-Factory, the leakage fields of the bending magnets, which will be installed near to the collision point, need to be as small as possible. For achieving this smaller leakage field, the authors propose a special superconducting dipole with a shield coil. A novel approach for achieving a leakage field of less than 5 mT at a radius of 200 mm, based on an active shield method, has been investigated. The design concept of the coil, which consists of a main coil and a shield coil having an opposite current to the main coil, has been developed. The coil design and the structure of the magnet are described.

Tsuchiya, K.; Kobayashi, T.M.; Haruyama, T.; Ajima, Y.; Doi, Y.; Ohuchi, N.; Kurokawa, S. [National Lab. for High Energy Physics, Ibaraki (Japan); Kimura, A. [Graduate Univ. for Advanced Studies, Ibaraki (Japan)

1994-12-31T23:59:59.000Z

325

Atomizing, continuous, water monitoring module  

DOE Patents (OSTI)

A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

Thompson, C.V.; Wise, M.B.

1997-07-08T23:59:59.000Z

326

Design and current-limiting simulation of magnetic-shield type superconducting fault current limiter with high-Tc superconductors  

SciTech Connect

The continuous development of electric power utilities has led to the increase in the problems concerning fault currents. The use of fault current limiters, which suppress fault currents below a prescribed level, has been examined in many places. The authors have studied a superconducting fault current limiter that is based on the magnetic shielding effect of superconductors. In this paper, the authors derive a requirement for leading to a flux-jumping inside a ceramic superconductor at liquid nitrogen temperature. Next, two kinds of magnetic-shield type superconducting fault current limiters are designed, and their current-limiting simulations are tried using a computer.

Kajikawa, K.; Kaiho, K.; Tamada, N. [Electrotechnical Lab., Tsukuba, Ibaraki (Japan)] [Electrotechnical Lab., Tsukuba, Ibaraki (Japan); Onishi, T. [Hokkaido Univ., Sapporo (Japan)] [Hokkaido Univ., Sapporo (Japan)

1996-07-01T23:59:59.000Z

327

Vibrational Modes of Adsorbed Atoms  

E-Print Network (OSTI)

for AronXe B. Neon Ar The lowest surface m ver g.ur ace mode branc mo d o' td 'th es of the " rin " ce e wit an adsorbate of modes assoc' tia ed with th e; there are for the ads stion, the bra h sorbate atoms I c 1.ons ranch labeled 2H s. n... , are the real ads teristic force con t tons ants for ad is evident that in Fi . 2 t "heavier" than th ig. the adsorbate is n e substrate M & terpretation b M, ) in tkis in- ecause the weaknes th l' ht ofth ds o ke adsorbate atoms (m, &m, IBRATIQNAI...

LAWRENCE, WR; Allen, Roland E.

1977-01-01T23:59:59.000Z

328

Relativistic atomic beam spectroscopy II  

SciTech Connect

The negative ion of H is one of the simplest 3-body atomic systems. The techniques we have developed for experimental study of atoms moving near speed of light have been productive. This proposal request continuing support for experimental studies of the H{sup -} system, principally at the 800 MeV linear accelerator (LAMPF) at Los Alamos. Four experiments are currently planned: photodetachment of H{sup -} near threshold in electric field, interaction of relativistic H{sup -} ions with matter, high excitations and double charge escape in H{sup -}, and multiphoton detachment of electrons from H{sup -}.

NONE

1989-12-31T23:59:59.000Z

329

Atomic-binding-energy oscillations  

Science Journals Connector (OSTI)

We investigate the oscillatory supplement to the statistical nonrelativistic binding-energy formula for neutral atoms. The semiclassical approach proves capable of deriving these oscillations. It turns out that their amplitude is proportional to Z4/3 (Z is the number of electrons), and that their period is determined by the maximum angular momentum available in Thomas-Fermi atoms, i.e., 0.928Z1/3. Our calculation also provides an understanding of the peculiar shape of the oscillations, which show sharp minima and wide, structured maxima.

Berthold-Georg Englert and Julian Schwinger

1985-07-01T23:59:59.000Z

330

Development and testing of an improved dosimetry system using a backscatter shielded electronic portal imaging device  

SciTech Connect

Purpose: To investigate the properties of a modified backscatter shielded electronic portal imaging device (BSS-EPID) and to develop a dose model to convert BSS-EPID images to dose in water as part of an improved system for dosimetry using EPIDs. Methods: The effectiveness of the shielding of the BSS-EPID was studied by comparing images measured with the BSS-EPID mounted on the support arm to images measured with the BSS-EPID removed from the support arm. A dose model was developed and optimized to reconstruct dose in water at different depths from measured BSS-EPID images. The accuracy of the dose model was studied using BSS-EPID images of 28 IMRT fields to reconstruct dose in water at depths of 2, 5, 10, and 20 cm and comparing to measured dose in water from a two-dimensional diode array at the same depths. The ability of the BSS-EPID system to operate independently of detector position was demonstrated by comparing the dose reconstruction of a 10 x 10 cm{sup 2} field using different detector offsets to that measured by a two-dimensional diode array. Results: The shielding of the BSS-EPID was found to be effective, with more than 99% of pixels showing less than 0.5% change due to the presence of the support arm and at most a 0.2% effect on the central axis for 2 x 2 cm{sup 2} fields to fully open 30 x 40 cm{sup 2} images. The dose model was shown to accurately reconstruct measurements of dose in water using BSS-EPID images with average {gamma} pass rates (2%, 2 mm criteria) of 92.5%, 98.7%, 97.4%, and 97.2% at depths of 2, 5, 10, and 20 cm, respectively, when compared to two-dimensional diode array measurements. When using 3%, 3 mm {gamma} criteria, the average pass rate was greater than 97% at all depths. Reconstructed dose in water for a 10 x 10 cm{sup 2} field measured with detector offsets as large as 10 cm agreed with each other and two-dimensional diode array measurements within 0.9%. Conclusions: The modified BSS-EPID and associated dose model provide an improved system for dosimetry measurements using EPIDs. Several important limitations of the current hardware and software are addressed by this system.

King, Brian W.; Morf, Daniel; Greer, Peter B. [School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales 2308 (Australia); Varian Medical Systems Imaging, Laboratory GmbH, Baden-Daettwil, CH-5405 (Switzerland); Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Newcastle, New South Wales 2310 (Australia) and School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales 2308 (Australia)

2012-05-15T23:59:59.000Z

331

The U. S. Department of Energy (DOE) has submitted a planned change request to use shielded containers for emplacement of selected remote-handled (RH) transuranic  

E-Print Network (OSTI)

that the use of shielded canisters for these waste streams has an insignificant impact on long-term performance the disruptions from in-the-wall emplacement of RH TRU waste canisters while providing additional storage shielded containers for emplacement of selected remote-handled (RH) transuranic (TRU) waste streams

332

A NEW ALGORITHM FOR RADIOISOTOPE IDENTIFICATION OF SHIELDED AND MASKED SNM/RDD MATERIALS  

SciTech Connect

Detection and identification of shielded and masked nuclear materials is crucial to national security, but vast borders and high volumes of traffic impose stringent requirements for practical detection systems. Such tools must be be mobile, and hence low power, provide a low false alarm rate, and be sufficiently robust to be operable by non-technical personnel. Currently fielded systems have not achieved all of these requirements simultaneously. Transport modeling such as that done in GADRAS is able to predict observed spectra to a high degree of fidelity; our research is focusing on a radionuclide identification algorithm that inverts this modeling within the constraints imposed by a handheld device. Key components of this work include incorporation of uncertainty as a function of both the background radiation estimate and the hypothesized sources, dimensionality reduction, and nonnegative matrix factorization. We have partially evaluated performance of our algorithm on a third-party data collection made with two different sodium iodide detection devices. Initial results indicate, with caveats, that our algorithm performs as good as or better than the on-board identification algorithms. The system developed was based on a probabilistic approach with an improved approach to variance modeling relative to past work. This system was chosen based on technical innovation and system performance over algorithms developed at two competing research institutions. One key outcome of this probabilistic approach was the development of an intuitive measure of confidence which was indeed useful enough that a classification algorithm was developed based around alarming on high confidence targets. This paper will present and discuss results of this novel approach to accurately identifying shielded or masked radioisotopes with radiation detection systems.

Jeffcoat, R.

2012-06-05T23:59:59.000Z

333

2013 R&D 100 Award: 'SHIELD' protects NIF optics from harmful pulses  

SciTech Connect

In the past, it took as long as 12 hours to manually screen 48 critical checkpoints at the National Ignition Facility (NIF) for harmful laser pulses. The screening equipment had to be moved from point to point throughout a facility the size of three football fields. Now with a new technology, called Laser SHIELD (Screening at High-throughput to Identify Energetic Laser Distortion), and with the push of a button, the screening can be done in less than one second. Proper screening of pulses is critical for the operation of high-energy lasers to ensure that the laser does not exceed safe operating conditions for optics. The energetic beams of light are so powerful that, when left uncontrolled, they can shatter the extremely valuable glass inside the laser. If a harmful pulse is found, immediate adjustments can be made in order to protect the optics for the facility. Laser SHIELD is a custom-designed high-throughput screening system built from low-cost and commercially available components found in the telecommunications industry. Its all-fiber design makes it amenable to the unique needs of high-energy laser facilities, including routing to intricate pick-off locations, immunity to electromagnetic interference and low-loss transport (up to several kilometers). The technology offers several important benefits for NIF. First, the facility is able to fire more shots in less time-an efficiency that saves the facility millions of dollars each year. Second, high-energy lasers are more flexible to wavelength changes requested by target physicists. Third, by identifying harmful pulses before they damage the laser's optics, the facility potentially saves hundreds of thousands of dollars in maintenance costs each year.

Chou, Jason

2014-04-03T23:59:59.000Z

334

Characterization of the Radiation Shielding Properties of US andRussian EVA Suits  

SciTech Connect

Reported herein are results from the Eril Research, Inc.(ERI) participationin the NASA Johnson Space Center sponsored studycharacterizing the radiation shielding properties of the two types ofspace suit that astronauts are wearing during the EVA on-orbit assemblyof the International Space Station (ISS). Measurements using passivedetectors were carried out to assess the shielding properties of the USEMU Suit and the Russian Orlan-M suit during irradiations of the suitsand a tissue equivalent phantom to monoenergetic proton and electronbeams at the Loma Linda University Medical Center (LLUMC). Duringirradiations of 6 MeV electrons and 60 MeV protons, absorbed dose as afunction of depth was measured using TLDs exposed behind swatches of thetwo suit materials and inside the two EVA helmets. Considerable reductionin electron dosewas measured behind all suit materials in exposures to 6MeV electrons. Slowing of the proton beam in the suit materials led to anincrease in dose measured in exposures to 60 MeV protons. During 232 MeVproton irradiations, measurements were made with TLDs and CR-39 PNTDs atfive organ locations inside a tissue equivalent phantom, exposed bothwith and without the two EVA suits. The EVA helmets produce a 13 to 27percent reduction in total dose and a 0 to 25 percent reduction in doseequivalent when compared to measurements made in the phantom head alone.Differences in dose and dose equivalent between the suit and non-suitirradiations forthe lower portions of the two EVA suits tended to besmaller. Proton-induced target fragmentation was found to be asignificant source of increased dose equivalent, especially within thetwo EVA helmets, and average quality factor inside the EMU and Orlan-Mhelmets was 2 to 14 percent greater than that measured in the barephantom head.

Benton, E.R.; Benton, E.V.; Frank, A.L.

2001-10-26T23:59:59.000Z

335

Flow distribution analysis on the cooling tube network of ITER thermal shield  

SciTech Connect

Thermal shield (TS) is to be installed between the vacuum vessel or the cryostat and the magnets in ITER tokamak to reduce the thermal radiation load to the magnets operating at 4.2K. The TS is cooled by pressurized helium gas at the inlet temperature of 80K. The cooling tube is welded on the TS panel surface and the composed flow network of the TS cooling tubes is complex. The flow rate in each panel should be matched to the thermal design value for effective radiation shielding. This paper presents one dimensional analysis on the flow distribution of cooling tube network for the ITER TS. The hydraulic cooling tube network is modeled by an electrical analogy. Only the cooling tube on the TS surface and its connecting pipe from the manifold are considered in the analysis model. Considering the frictional factor and the local loss in the cooling tube, the hydraulic resistance is expressed as a linear function with respect to mass flow rate. Sub-circuits in the TS are analyzed separately because each circuit is controlled by its own control valve independently. It is found that flow rates in some panels are insufficient compared with the design values. In order to improve the flow distribution, two kinds of design modifications are proposed. The first one is to connect the tubes of the adjacent panels. This will increase the resistance of the tube on the panel where the flow rate is excessive. The other design suggestion is that an orifice is installed at the exit of tube routing where the flow rate is to be reduced. The analysis for the design suggestions shows that the flow mal-distribution is improved significantly.

Nam, Kwanwoo; Chung, Wooho; Noh, Chang Hyun; Kang, Dong Kwon; Kang, Kyoung-O; Ahn, Hee Jae; Lee, Hyeon Gon [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

2014-01-29T23:59:59.000Z

336

Super-high-frequency shielding properties of excimer-laser-synthesized-single-wall-carbon-nanotubes/polyurethane nanocomposite films  

SciTech Connect

Electromagnetic shielding attenuation (ESA) properties of carbon nanotubes/polymer nanocomposite films, in the super high frequency (SHF) X-band (7-12 GHz) domain are studied. The nanocomposite films consisted of thermoset polyurethane (PU) resin blended with single-walled carbon nanotubes (SWCNTs) mats, and deposited on fused quartz substrates. Two different approaches were used to achieve the nanocomposite films, namely (i) through the on-substrate ''all-laser'' growth approach of SWCNTs directly onto substrate, followed by their infiltration by the PU resin, and (ii) by appropriately dispersing the chemically-purified SWCNTs (in the soot form) into the PU matrix and their subsequent deposition onto quartz substrates by means of a solvent casting process. Characterizations of the ESA properties of the developed nanocomposite films show that they exhibit systematically a deep shielding band, centered at around 9.5 GHz, with an attenuation as high as |- 30| dB, recorded for SWCNT loads of 2.5 wt. % and above. A direct correlation is established between the electrical conductivity of the nanocomposite films and their electromagnetic shielding capacity. The SWCNTs/PU nanocomposites developed here are highly promising shielding materials as SHF notch filters, as their ESA capacity largely exceeds the target value of |- 20| dB generally requested for commercial applications.

Aiessa, B.; Habib, M. A.; Denidni, T. A.; El Khakani, M. A. [Institut National de la Recherche Scientifique, INRS-Energie, Materiaux et Telecommunications, 1650 Blvd. Lionel Boulet, C.P. 1020, Varennes, Quebec, J3X 1S2 (Canada); Laberge, L. L.; Therriault, D. [Mechanical Engineering Department, Ecole Polytechnique de Montreal, P.O. Box 6079, Montreal, H3C 3A7 (Canada)

2011-04-15T23:59:59.000Z

337

Estimation of the minimum shielding failure flashover current for first and subsequent lightning strokes to overhead transmission lines  

Science Journals Connector (OSTI)

Abstract ATP-EMTP simulations are performed to estimate the minimum shielding failure current causing flashover in overhead transmission lines with operating voltage in the range of 66kV up to 735kV. This critical current, affecting shielding failure flashover rate, is of great importance for assessing the insulation coordination of overhead transmission lines and the connected substations. The minimum shielding failure current causing flashover of line insulation is highly dependent upon insulator string flashover modelling and, also, markedly higher than that calculated according to the relevant IEEE Std 1243-1997 simplified expression. A modification of the latter is suggested by using multiplication factors of 1.5 and 1.65 for first and subsequent lightning strokes, respectively, so as to account for the increased dielectric strength of line insulator strings under non-standard lightning overvoltage surges. Alternatively, the critical currents can be respectively estimated by using average negative breakdown gradients per unit length of insulator string of 680kV/m and 750kV/m. The shielding failure flashover rate of the overhead transmission lines, being greatly influenced by insulator string flashover modelling, is lower than that obtained based on the critical current according to IEEE Std 1243-1997.

Zacharias G. Datsios; Pantelis N. Mikropoulos; Thomas E. Tsovilis

2014-01-01T23:59:59.000Z

338

Calibration of the axafhrc UV/Ion shields at Osservatorio Astronomico di Palermo G.S. Vaiana: I Instrumental setup  

E-Print Network (OSTI)

in the calibration of the AXAF­HRC UV/ion shield. The facility has been expanded to improve its performance been expanded. In particular, the addition of a UV beam line including a grazing incidence on cryogenic pumps for the chamber and on a magnetic levitation turbo molecular p

339

Above: Power deposition in the superconducting magnets and the tungsten-carbide + water shield inside them, according to a  

E-Print Network (OSTI)

jet will disrupt the pool, unless mitigated by a splash suppressor. A SOLENOID CAPTURE SYSTEM Collider (MC) Comments Beam Power 4 MW No existing target system will survive at this power Ep 8 GeV yieldAbove: Power deposition in the superconducting magnets and the tungsten-carbide + water shield

McDonald, Kirk

340

Anticipating the atom: popular perceptions of atomic power before Hiroshima  

E-Print Network (OSTI)

to spontaneously generate light and heat. s Theory chased research after the turn of the century. Rutherford and his partner Frederick Soddy, in Montreal in 1902, noticed that the heaviest radioactive elements were slowly changing into lighter elements, throwing... the Atlantic. More importantly, in 1908, the final chapter of Frederick Soddy's The Jnterpretati on of Radium, a collection of six free popular lectures given at the University of Glasgow, speculated on the possibility of controlling the rate of atomic...

d'Emal, Jacques-Andre Christian

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Shielded Payload Containers Will Enhance the Safety and Efficiency of the DOE's Remote Handled Transuranic Waste Disposal Operations  

SciTech Connect

The Waste Isolation Pilot Plant (WIPP) disposal operation currently employs two different disposal methods: one for Contact Handled (CH) waste and another for Remote Handled (RH) waste. CH waste is emplaced in a variety of payload container configurations on the floor of each disposal room. In contrast, RH waste is packaged into a single type of canister and emplaced in pre-drilled holes in the walls of disposal rooms. Emplacement of the RH waste in the walls must proceed in advance of CH waste emplacement. This poses a significant logistical constraint on waste handling operations by requiring significant coordination between waste characterization and preparations for shipping among the various generators. To improve operational efficiency, the Department of Energy (DOE) is proposing a new waste emplacement process for certain RH waste streams that can be safely managed in shielded containers. RH waste with relatively low gamma-emitting activity would be packaged in lead-lined containers, shipped to WIPP in existing certified transportation packages for CH waste, and emplaced in WIPP among the stacks of CH waste containers on the floor of a disposal room. RH waste with high gamma-emitting activity would continue to be emplaced in the boreholes along the walls. The new RH container appears essentially the same as a nominal 208-liter drum, but is built with about 2.5 cm of lead, sandwiched between thick steel sheet. The top and bottom are made of very thick plate steel, for strengthening the package to meet transportation requirements, and provide similar gamma attenuation. This robust configuration provides an overpack for waste that otherwise would be remotely handled. Up to a 3:1 reduction in number of shipments is projected if RH waste were transported in the proposed shielded containers. This paper describes the container design and testing, as well as the regulatory approach used to meet the requirements that apply to WIPP and its associated transportation system. This paper describes the RH transuranic waste inventory that may be candidates for packaging and emplacement in shielded containers. DOE does not propose to use shielded containers to increase the amount of RH waste allowed at WIPP. DOE's approach to gain approval for the transportation of shielded containers and to secure regulatory approval for use of shielded containers from WIPP regulators is discussed. Finally, the paper describes how DOE proposes to count the waste packaged into shielded containers against the RH waste inventory and how this will comply with the volume and radioactivity limitations imposed in the many and sometimes overlapping regulations that apply to WIPP. (authors)

Nelson, R.A. [U. S. Department of Energy, Carlsbad, New Mexico (United States); White, D.S. [Washington Group International, Carlsbad, New Mexico (United States)

2008-07-01T23:59:59.000Z

342

Shielding and criticality analyses of phase I reference truck and rail cask designs for spent nuclear fuel  

SciTech Connect

Results are presented herein to determine the adequacy with respect to shielding regulations of reference designs for a truck cask containing 2 PWR or 5 BWR assemblies of standard burnup (45 GWd/MTU for PWR, 40 GWd/MTU for BWR) and 1 PWR assembly with extended burnup (55 GWd/MTU). The study also includes reference and modified rail cask designs with projected payloads of 8, 10, or 12 PWR assemblies. The burnup/age trends are analyzed in one dimension for both Pb and depleted uranium (DU) gamma-ray shields. The results of the two-dimensional shielding analysis uphold the one-dimensional results as being an appropriate means of studying the burnup/age trends for the truck cask. These results show that the reference design for the Pb-shield truck cask is inadequate for all cases considered, while the DU-shield truck cask is capable of carrying the desired payloads. The one-dimensional shielding analysis results for the reference Pb and DU rail casks indicate substantial margins exist in the side doses for reasonable burnup/age combinations. For a Pb-cask configuration, margins exist primarily for long-cooled (15 years) fuel. For the modified Pb and DU rail casks, the 2-m dose rates offer substantial margins below the regulatory limits for all burnup values considered provided the spent fuel has cooled for {>=}10 years. The modified Pb and DU casks yield essentially identical results and, hence, could be considered equivalent from a shielding perspective. The criticality analyses that were performed indicate that a truck basket can be designed to provide an adequate subcritical margin for 2 PWR assemblies enriched to 5 wt%. While the 10- and 12- assembly rail cask designs are very close to the regulatory limit of 0.95 for k{sub eff}, after accounting for a 0.01 {Delta}k bias and 2 standard deviations, the limit is exceeded by about 3%. It is believed that a combination of decreased enrichments and/or increased water gaps should allow these baskets to be acceptable.

Broadhead, B.L.; Childs, R.L.; Parks, C.V.

1996-03-01T23:59:59.000Z

343

Manhattan Project: Los Alamos Scientists  

Office of Scientific and Technical Information (OSTI)

Resources Resources About this Site How to Navigate this Site Library Maps Note on Sources Nuclear Energy and the Public's Right to Know Photo Gallery Site Map Sources and Notes Suggested Readings LOS ALAMOS SCIENTISTS Los Alamos (Laboratory) (August 1946) Resources > Photo Gallery Los Alamos, August 1946 Scientists attending a colloquium at Los Alamos, August 1946. Left to right, first row: Norris E. Bradbury, John H. Manley, Enrico Fermi, J. M. B. Kellogg. Second row: Robert Oppenheimer, Richard P. Feynman, Phil B. Porter. Third row: Gregory Breit (partially hidden), Arthur Hemmendinger, Arthur D. Schelberg. The photograph is courtesy Los Alamos National Laboratory. The identifications are from Richard G. Hewlett and Francis Duncan, Atomic Shield, 1947-1952: Volume II, A History of the United States Atomic Energy Commission (Washington: U.S. Atomic Energy Commission, 1972), opposite page 46.

344

Preliminary steps to the Atomic Energy Commission  

NLE Websites -- All DOE Office Websites (Extended Search)

steps to the Atomic Energy Commission By October 1946, General Groves had seen the writing on the wall. The Manhattan District was destined to give up the atomic energy program to...

345

Moving closer to the Atomic Energy Commission  

NLE Websites -- All DOE Office Websites (Extended Search)

Moving closer to the Atomic Energy Commission Last week we examined some events in Oak Ridge resulting from the struggle for control of atomic weapons. There was also a transition...

346

UNITED STATES ATOMIC ENERGY COMMISSION  

Office of Legacy Management (LM)

I(S.0 -01: I(S.0 -01: SPECIAL NUCLEAR MATERIAL LlCEWSE Pursuant to the Atomic Energy Act of 1954 and Title 10, Code of Federal Regulations, Chapter 1, Part 70, "Special Nuclear Material Regulations," o. license is hereby issued authorizing the licensee to receive and possess the special nuclear material designated below; to use such special nuclear material for the purpose(s) and at the place(s) designated below; and to transfer such material to persons' authorized to receive it in accordance with the regulations in said Port. This license shall be deemed to contain the conditions specified in Section 70.32(a) of said regulations, and is subject to all applicable rules, regtdations, and orders of the Atomic Energy Commission now or hereafter in

347

The Modified Embedded Atom Method  

SciTech Connect

Recent modifications have been made to generalize the Embedded Atom Method (EAM) to describe bonding in diverse materials. By including angular dependence of the electron density in an empirical way, the Modified Embedded Atom Method (MEAM) has been able to reproduce the basic energetic and structural properties of 45 elements. This method is ideally suited for examining the interfacial behavior of dissimilar materials. This paper explains in detail the derivation of the method, shows how the parameters of the MEAM are determined directly from experiment or first principles calculations, and examines the quality of the reproduction of the database. Materials with fcc, bcc, hcp, and diamond cubic crystal structure are discussed. A few simple examples of the application of the MEAM to surfaces and interfaces are presented. Calculations of pullout of a SiC fiber in a diamond matrix as a function of applied stress show non-uniform deformation of the fiber.

Baskes, M.I.

1994-08-01T23:59:59.000Z

348

Muon bremsstrahlung on heavy atoms  

Science Journals Connector (OSTI)

The cross section for high energy muon bremsstrahlung on heavy atoms is calculated without the use of the Born approximation. It is shown that the correction to the Born approximation in the region of momentum transfers q of the order of ?c has the same order of magnitude as the well-known correction of Davies, Bethe, and Maximon. It is shown also that these corrections have different signs and nearly compensate each other.

Yu. M. Andreev and E. V. Bugaev

1997-02-01T23:59:59.000Z

349

The Future of Atomic Energy  

DOE R&D Accomplishments (OSTI)

There is definitely a technical possibility that atomic power may gradually develop into one of the principal sources of useful power. If this expectation will prove correct, great advantages can be expected to come from the fact that the weight of the fuel is almost negligible. This feature may be particularly valuable for making power available to regions of difficult access and far from deposits of coal. It also may prove a great asset in mobile power units for example in a power plant for ship propulsion. On the negative side there are some technical limitations to be applicability of atomic power of which perhaps the most serious is the impossibility of constructing light power units; also there will be some peculiar difficulties in operating atomic plants, as for example the necessity of handling highly radioactive substances which will necessitate, at least for some considerable period, the use of specially skilled personnel for the operation. But the chief obstacle in the way of developing atomic power will be the difficulty of organizing a large scale industrial development in an internationally safe way. This presents actually problems much more difficult to solve than any of the technical developments that are necessary, It will require an unusual amount of statesmanship to balance properly the necessity of allaying the international suspicion that arises from withholding technical secrets against the obvious danger of dumping the details of the procedures for an extremely dangerous new method of warfare on a world that may not yet be prepared to renounce war. Furthermore, the proper balance should be found in the relatively short time that will elapse before the 'secrets' will naturally become open knowledge by rediscovery on part of the scientists and engineers of other countries.

Fermi, E.

1946-05-27T23:59:59.000Z

350

Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys...  

NLE Websites -- All DOE Office Websites (Extended Search)

Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction Reaction. Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction...

351

Classical Radiative Cascade in Antiproton Atoms  

SciTech Connect

An interrelation between radiative cascade transitions and annihilation rates in antiproton atoms is considered. The population of antiproton atom energy levels is described by a classical distribution function f(n,l), determining intensities of spectral lines in antiproton atoms. A strong dependence of spectral line intensities on the nuclear size is shown which could be used for the determination of effective nuclear radius.

Bureyeva, L. [Institute of Spectroscopy of the RAS, Troitsk, Moscow Reg., 142190 (Russian Federation); Lisitsa, V. [Nuclear Fusion Institute, Russian Research Center 'Kurchatov Institute' Moscow (Russian Federation); Putlitz, G. zu [Physikalisches Institut, Universitaet Heidelberg, Philosophenweg 12, 69120 Heidelberg (Germany)

2005-10-26T23:59:59.000Z

352

Sources of polarized ions and atoms  

SciTech Connect

In this presentation we discuss methods of producing large quantities of polarized atoms and ions (Stern-Gerlach separation, optical pumping, and spin-exchange) as well as experimental methods of measuring the degree of polarization of atomic systems. The usefulness of polarized atoms in probing the microscopic magnetic surface properties of materials will also be discussed. 39 refs., 5 figs., 2 tabs.

Cornelius, W.D.

1988-01-01T23:59:59.000Z

353

Atoms, photons, and Information Andrew Silberfarb  

E-Print Network (OSTI)

Atoms, photons, and Information by Andrew Silberfarb B.S. California Institute of Technology, 1998 #12;Atoms, photons, and Information by Andrew Silberfarb ABSTRACT OF DISSERTATION Submitted in Partial Albuquerque, New Mexico March, 2006 #12;Atoms, photons, and Information by Andrew Silberfarb B.S. California

Deutsch, Ivan H.

354

Stark spectroscopy on rare gas atoms  

E-Print Network (OSTI)

Stark spectroscopy on rare gas atoms PROEFSCHRIFT ter verkrijging van de graad van doctor aan de-DATA LIBRARY TECHNISCHE UNIVERSITEIT EINDHOVEN Jiang, Tao Stark spectroscopy on rare gas atoms / by Tao Jiang / gasontladingen Subject headings : plasma diagnostics / Stark effect / optogalvanic spectroscopy / atomic emission

Eindhoven, Technische Universiteit

355

The Reaction of Hydrogen Atoms with Ethylene  

Science Journals Connector (OSTI)

...research-article The Reaction of Hydrogen Atoms with Ethylene M. P. Halstead D. A. Leathard R...the reaction between hydrogen atoms and ethylene in a discharge-flow system at 290 3...argon were used and the hydrogen atom and ethylene flow rates were in the ranges 5 to 10...

1970-01-01T23:59:59.000Z

356

Riso Report No. Danish Atomic Energy Commission  

E-Print Network (OSTI)

fM O o 8- OL '·O c/i Riso Report No. Danish Atomic Energy Commission Research Establishment Riso/t on exchangefrom: Library, Danish Atomic Energy Commission, Risd, Roskilde, Denmark #12;May, 1966 Ris6 Report No Jagiellonski Institute of Physics Krakow, Poland and P. A. Lindgård Mogensen The Danish Atomic Energy

357

Danish Atomic Energy Commission Research Establishment Riso  

E-Print Network (OSTI)

10 Ol CM l-l I S l ^. n ·H Danish Atomic Energy Commission Research Establishment Riso Chemistry Atomic Energy Commission Z. Fordos, Concrete Research Laboratory Karlstrup M. Skytte, Betonvarefabriken. E. Bjergbakke, Accelerator Dept. Danish Atomic Energy Commission Z. FSrdos, Concrete Research

358

so Ris Report * Danish Atomic Energy Commission  

E-Print Network (OSTI)

so Risø Report r- 6 §* Danish Atomic Energy Commission 2 Research Establishment Risø Incorporation Commission Research Establishment Risø by lb Larsen Danish Atomic Energy Commission Research Establishment in Bitumen of Low-Level Radioactive Waste Water Evaporator Concentrate at the Danish Atomic Energy Com

359

Left alone, palladium atoms get the job done | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

Left alone, palladium atoms get the job done Left alone, palladium atoms get the job done Isolated atoms tackle carbon monoxide, potentially reducing engine emissions A vehicle's...

360

Self-corrected Sensors Based On Atomic Absorption Spectroscopy...  

NLE Websites -- All DOE Office Websites (Extended Search)

corrected Sensors Based On Atomic Absorption Spectroscopy For Atom Flux Measurements In Molecular Beam Epitaxy. Self-corrected Sensors Based On Atomic Absorption Spectroscopy For...

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Understanding Atom Probe Tomography of Oxide-Supported Metal...  

NLE Websites -- All DOE Office Websites (Extended Search)

Atom Probe Tomography of Oxide-Supported Metal Nanoparticles by Correlation with Atomic Resolution Electron Understanding Atom Probe Tomography of Oxide-Supported Metal...

362

'Recommended by Duncan Hines': Automobility, Authority, and American Gastronomy  

E-Print Network (OSTI)

of cultures of automobility, consumption, and authority, I frame Hines as a mediator between producers and consumers, a position gaining in significance in the early 20th century. Narrating the exchange of commodities, Hines' gastronomy acted as a fount...

Talbott, Damon Lee

2008-06-09T23:59:59.000Z

363

QuickStart: Learn DAX Basics in 30 Owen Duncan  

E-Print Network (OSTI)

. Why is DA It's easy to PivotCharts critical sale inventory d important c data. When line info o it. You can ev AX formulas. Bu date ranges? O mulas provide formulas will he e real business cel

Hunt, Galen

364

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light  

E-Print Network (OSTI)

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light and then trapped in a bottle whose "walls" are magnetic fields. Cooled atoms are ideal for exploring basic. research has traditionally been the study of the intrinsic prop erties of isolated atoms. In the early part

Johannesson, Henrik

365

Atomic flux measurement by diode-laser-based atomic absorption spectroscopy  

E-Print Network (OSTI)

Atomic flux measurement by diode-laser-based atomic absorption spectroscopy Weizhi Wang,a) R. H, California 94305 Received 5 May 1999; accepted 6 June 1999 Diode-laser-based atomic absorption AA sensors- quirements, and only the QCM measures the flux. Lamp- based atomic absorption AA sensors have been success

Fejer, Martin M.

366

NAAP Hydrogen Atom 1/9 The Hydrogen Atom Student Guide  

E-Print Network (OSTI)

Name: NAAP ­ Hydrogen Atom 1/9 The Hydrogen Atom ­ Student Guide Background Material Carefully read and the Quantum model represent the Hydrogen atom. In some cases they both describe things in the same way frequency, smaller energy, and the same velocity through space as a blue photon". #12;NAAP ­Hydrogen Atom 2

Farritor, Shane

367

The 1993 atomic mass evaluation: (I) Atomic mass table  

Science Journals Connector (OSTI)

This paper is the first of a series of four. In it, a table is given to replace the 1983 atomic mass table. The differences with the earlier table are briefly discussed and information is given of interest for the users of this table. Part II of this series gives values for several derived quantities (decay-, separation- and reaction energies), part III shows graphs of several of those quantities, and part IV gives a list of input data and full information on the used input data and on the procedures used in deriving the tables in the preceding parts.

G. Audi; A.H. Wapstra

1993-01-01T23:59:59.000Z

368

CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT  

Office of Legacy Management (LM)

WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT EAST PITTSBURGH PLANT FOREST HILLS PITTSBURGH, PENNSYLVANIA Department of Energy Office of Nuclear Energy Office of Terminal Waste Disposal and Remedial Action Division of Remedial Action Projects ..-.. --__- _".-.-l--_--l -_._ _- --- ~~~. . ..~ CONTENTS Page - - I NTRODUCTI ON 1 Purpose 1 Docket Contents 1 Exhibit I: Summary of Activities at Westinghouse Atomic Power Development Plant, East Pittsburgh Plant, Forest Hills, Pittsburgh, Pennsylvania I-l Exhibit II: Documents Supporting the Certification of Westinghouse Atomic Power Development Plant, East Pittsburgh Plant, Forest Hills, Pittsburgh, Pennsylvania iii II-1 . . .- .__.^ I ^_... _.-__^-____-. - CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT

369

Princeton Plasma Physics Lab - General Atomics (GA)  

NLE Websites -- All DOE Office Websites (Extended Search)

general-atomics-ga General general-atomics-ga General Atomics en The Scorpion's Strategy: "Catch and Subdue" http://www.pppl.gov/node/1132

American Fusion News Category: 
atomics-ga">General Atomics (GA)
370

Electromagnetically induced grating with maximal atomic coherence  

SciTech Connect

We describe theoretically an atomic diffraction grating that combines an electromagnetically induced grating with a coherence grating in a double-{Lambda} atomic system. With the atom in a condition of maximal coherence between its lower levels, the combined gratings simultaneously diffract both the incident probe beam as well as the signal beam generated through four-wave mixing. A special feature of the atomic grating is that it will diffract any beam resonantly tuned to any excited state of the atom accessible by a dipole transition from its ground state.

Carvalho, Silvania A.; Araujo, Luis E. E. de [Instituto de Fisica ''Gleb Wataghin'', Universidade Estadual de Campinas, Campinas-SP, 13083-859 Sao Paulo (Brazil)

2011-10-15T23:59:59.000Z

371

Laser-induced "two-atom" coherence  

Science Journals Connector (OSTI)

Our analysis shows that if an electromagnetic field excites a coherent superposition of states of two different types of atoms, then the results of a collision of those two atoms can be quite different from the usual dephasing that a coherently excited atom suffers upon collision with another atom. We present the concept of "two-atom" coherence as one feature of this interaction where the field of a given wavelength may interact with the system coherently over a wide range of internuclear distances.

Munir H. Nayfeh and G. B. Hillard

1984-04-01T23:59:59.000Z

372

The Atomic Energy Commission By Alice Buck  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Atomic Energy Atomic Energy Commission By Alice Buck July 1983 U.S. Department of Energy Office of Management Office of the Executive Secretariat Office of History and Heritage Resources 1 Introduction Almost a year after World War II ended, Congress established the United States Atomic Energy Commission to foster and control the peacetime development of atomic science and technology. Reflecting America's postwar optimism, Congress declared that atomic energy should be employed not only in the Nation's defense, but also to promote world peace, improve the public welfare, and strengthen free competition in private

373

Atomic Structure Calculations from the Los Alamos Atomic Physics Codes  

DOE Data Explorer (OSTI)

The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

Cowan, R. D.

374

Manhattan Project: Atomic Discoveries, 1890s-1939  

Office of Scientific and Technical Information (OSTI)

Excerpt from the comic book "Adventures Inside the Atom." Click on this image or visit the "Library" to view the whole comic book. ATOMIC DISCOVERIES Excerpt from the comic book "Adventures Inside the Atom." Click on this image or visit the "Library" to view the whole comic book. ATOMIC DISCOVERIES (1890s-1939) Events A Miniature Solar System, 1890s-1919 Exploring the Atom, 1919-1932 Atomic Bombardment, 1932-1938 The Discovery of Fission, 1938-1939 Fission Comes to America, 1939 Philosophers of Ancient Greece reasoned that all matter in the universe must be composed of fundamental, unchangeable, and indivisible objects, which they called "atoma" ("ατoµα"). The exact nature of these atoms remained elusive, however, despite centuries of attempts by alchemists to create a "philosopher's stone" that could transmute atoms of lead to gold, prove the Greeks wrong, and make its inventors Modern model of an atom very rich. It was only in the late 1890s and the early twentieth-century that this view of a solid atom, bouncing around the universe like a billiard ball, was replaced by an atom that resembled more a miniature solar system, its electrons orbiting around a small nucleus. Explorations into the nature of the atom from 1919 to 1932 confirmed this new model, especially with Ernest Rutherford's 1919 success in finally transmuting an atom of one substance into another and with James Chadwick's 1932 discovery of the elusive final basic particle of the atom, the neutron. From 1932 to 1938, scientists around the world learned a great deal more about atoms, primarily by bombarding the nuclei of atoms and using a variety of particle accelerators. In 1938, word came from Berlin of the most startling result of them all: the nucleus of an atom could actually be split in two, or "fissioned." This breakthrough was quickly confirmed in the United States and elsewhere. According to the theories of Albert Einstein, the fission of an atom should result in a release of energy. An "atomic bomb" was now no longer just science fiction -- it was a distinct possibility.

375

Atomic Spectroscopy and Separated Isotopes  

Science Journals Connector (OSTI)

The advantages in the use of separated isotopes in atomic spectroscopy for the determination of nuclear momentsI ? Q and for studies of the isotope-shift phenomena are discussed. Illustrations of spectra are given for mercury uranium and samarium. In addition a summary is given of twenty-two so-called problem nuclei i.e. those naturally occurring isotopes for which the nuclear moments are completely uncertain. Concluding remarks are made on such problems as the evaluation of the absolute magnitude of isotope shifts the role of forbidden transitions in isotope spectra and the potential future value of spectro-isotopic assay techniques.

J. R. McNally Jr.

1952-01-01T23:59:59.000Z

376

CACI: The Cesium-137 Agricultural Commodities Irradiator. Final design report: Volume 6, Shielding, mechanical, and electrical  

SciTech Connect

This report provides a complete description of the final detailed design of the Cesium-137 Agricultural Commodities Irradiator (CACI). The design was developed and successfully completed by the Rocketdyne Division of Rockwell International for the US Department of Energy (DOE). The CACI project was initiated in April 1985 under DOE`s Byproducts Utilization Program, with the objectives of transferring food irradiation technology to the industry and thereby demonstrating a beneficial use for the {sup 137}Cs nuclear by-product isotope. As designed, CACI will meet the intended requirements for research, development, and demonstration of irradiation processing of food. Further, as shown in the safety analyses performed during the project, the design conforms to all the safety and licensing requirements set forth for the project. The original scope of the CACI project included completion of its construction. However, the project was terminated for the convenience of the government during the final design phase in February 1986 for lack of a specific site. This Volume, VI, provides the CACI final design features regarding shielding, mechanical and electrical.

Not Available

1986-12-19T23:59:59.000Z

377

CACI: The Cesium-137 Agricultural Commodities Irradiator. Final design report: Volume 8, Shielding window  

SciTech Connect

This report provides a complete description of the final detailed design of the Cesium-137 Agricultural Commodities Irradiator (CACI). The design was developed and successfully completed by the Rocketdyne Division of Rockwell International for the US Department of Energy (DOE). The CACI project was initiated in April 1985 under DOE`s Byproducts Utilization Program, with the objectives of transferring food irradiation technology to the industry and thereby demonstrating a beneficial use for the 137 Cs nuclear by-product isotope. As designed, CACI will meet the intended requirements for research, development, and demonstration of irradiation processing of food. Further, as shown in the safety analyses performed during the project, the design conforms to all the safety and licensing requirements set forth for the project. The original scope of the CACI project included completion of its construction. However, the project was terminated for the convenience of the government during the final design phase in February 1986 for lack of a specific site. The CACI final design is described in eight volumes. This volume Volume III, describes the Shielding Window.

Not Available

1986-12-19T23:59:59.000Z

378

Effect of pressure and shielding gas on the microstructure of hyperbaric metal cored GMAW welds down to 111 bar  

SciTech Connect

The microstructural evolution of hyperbaric C-Mn weld metals was studied by means of bead-on-plate welds deposit with GMAW process using a commercial metal cored wire. The welding was carried out in the flat position in the range of 51 bar to 111 bar with He+ CO{sub 2} as shielding gas, which CO{sub 2} content varied from 0.1% to 0.8 %. The microstructures were quantitatively analyzed by optical microscopy to evaluate the amount of constituents according to the IIW/IIS terminology. The results showed that all weld metals presented great amounts of acicular ferrite and a stronger influence of pressure on microstructure compared to the influence of the shielding gas.

Jorge, J.C.F. [CEFET, Rio de Janeiro (Brazil). Mechanical Engineering Dept.; Santos, V.R. dos [Petrobras/CENPES, Rio de Janeiro (Brazil); Santos, J.F. dos [GKSS Forschungszentrum Geesthacht GmbH (Germany)

1995-12-31T23:59:59.000Z

379

Constraints on target chamber first wall and target designs that will enable NIF debris shields to survive  

SciTech Connect

The National Ignition Facility target chamber interior materials and target designs themselves have to be compatible with survival of the final-optics debris shields. To meet the planned maintenance and refinishing rate, the contamination of the debris shields cannot exceed about 1 nm equivalent thickness per shot of total material. This implies that the target mass must be limited to no more than 1 gram and the ablated mass released to the chamber from all other components must not exceed 3 grams. In addition, the targets themselves must either completely vaporize or send any minor amounts of shrapnel towards the chamber waist to prevent excessive cratering of the debris shields. The constraints on the first-wall ablation require that it be louvered to provide passive collection of remobilized contamination, because the expected target debris will remobilize at a rate fast enough to require cleaning every 3 weeks, about three times more frequent than possible with planned robotics. Furthermore, a comparison of ablatants from B{sub 4}C and stainless-steel louvers suggests that remobilization of target debris by x rays will be greater than of the base material in both cases, thereby reducing the performance advantage of clean B{sub 4}C over much-cheaper stainless steel. Neutronics calculations indicate that activation of thin Ni-free stainless steel is not a significant source of maintenance personnel radiation dose. Consequently, the most attractive first wall design consists of stainless-steel louvers. Evaluation of various unconverted-light beam dump designs indicates that stainless steel louvers generate no more debris than other materials, so one single design can serve as both first wall and beam dumps, eliminating beam steering restrictions caused by size and location of the beam dumps. One reservation is that the allowable contamination rate of the debris shield is not yet completely understood.

Hibbard,W.; Burnham, A. K.; Curran, D. R; Genin, F. Y.; Gerassimenko, M.; Latkowski, J. F.; Peterson, P. F.; Scott, J. M.; Tokheim, R. E.; Whitman, P. K.

1998-07-09T23:59:59.000Z

380

The new solid target system at UNAM in a self-shielded 11 MeV cyclotron  

SciTech Connect

A dual beam line (BL) self-shielded RDS 111 cyclotron for radionuclide production was installed at the School of Medicine of the National Autonomous University of Mexico in 2001. One of the BL's was upgraded to Eclipse HP (Siemens) in 2008 and the second BL was recently upgraded (June 2011) to the same version with the option for the irradiation of solid targets for the production of metallic radioisotopes.

Zarate-Morales, A.; Gaspar-Carcamo, R. E.; Lopez-Rodriguez, V.; Flores-Moreno, A.; Trejo-Ballado, F.; Avila-Rodriguez, Miguel A. [Unidad PET, Facultad de Medicina, Universidad Nacional Autonoma de Mexico, 04510 , D.F. Mexico (Mexico)

2012-12-19T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Safety evaluation for packaging (onsite) for the concrete-shielded RH TRU drum for the 327 Postirradiation Testing Laboratory  

SciTech Connect

This safety evaluation for packaging authorizes onsite transport of Type B quantities of radioactive material in the Concrete Shielded Remote-Handled Transuranic Waste (RH TRU) Drum per HNF-PRO-154, Responsibilities and Procedures for all Hazardous Material Shipments. The drum will be used for transport of 327 Building legacy waste from the 300 Area to a solid waste storage facility on the Hanford Site.

Smith, R.J.

1998-03-31T23:59:59.000Z

382

Sensing mode atomic force microscope  

DOE Patents (OSTI)

An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.

Hough, Paul V. C. (Port Jefferson, NY); Wang, Chengpu (Upton, NY)

2003-01-01T23:59:59.000Z

383

Hydrogen Atom in Relativistic Motion  

E-Print Network (OSTI)

The Lorentz contraction of bound states in field theory is often appealed to in qualitative descriptions of high energy particle collisions. Surprisingly, the contraction has not been demonstrated explicitly even in simple cases such as the hydrogen atom. It requires a calculation of wave functions evaluated at equal (ordinary) time for bound states in motion. Such wave functions are not obtained by kinematic boosts from the rest frame. Starting from the exact Bethe-Salpeter equation we derive the equal-time wave function of a fermion-antifermion bound state in QED, i.e., positronium or the hydrogen atom, in any frame to leading order in alpha. We show explicitly that the bound state energy transforms as the fourth component of a vector and that the wave function of the fermion-antifermion Fock state contracts as expected. Transverse photon exchange contributes at leading order to the binding energy of the bound state in motion. We study the general features of the corresponding fermion-antifermion-photon Fock states, and show that they do not transform by simply contracting. We verify that the wave function reduces to the light-front one in the infinite momentum frame.

M. Jarvinen

2005-04-11T23:59:59.000Z

384

Field application of EMI coatings investigation of coating materials and stylus electroplating protocols for shielded facilities. Final report  

SciTech Connect

To maintain reliable electromagnetic interference (EMI) shielding for electronic equipment shelter interfaces, mating surfaces such as doors and interfaces must provide low contact resistances and be resistant to excessive amounts of corrosion and mechanical wear that would tend to degrade their shielding integrity. The objective of this research was to establish the efficacy of stylus electroplating as a potentially viable field maintenance/repair technique for application of corrosion resistant, wear resistant coatings in order to help maintain the shielding integrity of those interfaces. Aluminum alloy (6061-T6) knife-edge and channel test pieces were stylus electroplated with tin or tin-lead coatings with nickel or copper underlayers. A custom-designed electroplating tool developed for electroplating the complex geometry of a knife-edge substrate appears to provide better control of the plating process and circumvents possible interference with previously deposited areas. This research has resulted in an optimized procedure for producing coatings that exhibit greater adherence, better uniformity, less scarring, and fewer blisters and ridges compared to those previously reported. An optimum electroplating strategy is suggested, which includes applying tin or tin-lead top layers over a thick layer of copper and a thin nickel strike.

Stephenson, L.D.; Donoho, L.H.

1996-03-01T23:59:59.000Z

385

GPS derived co-seismic and post-seismic effects of recent earthquakes on peninsular Indian shield and its tectonic implications  

Science Journals Connector (OSTI)

Several major earthquakes affected the stable continental Indian peninsular shield in recent past due to the activity of fault movements. This necessitates identifying the active faults in the region for future m...

S. K. Som; Vijay Shivgotra; Ashim Saha

2010-11-01T23:59:59.000Z

386

SPECIES RECOGNITION IS DRIVING EVOLUTION OF THE ACOUSTIC MATING SYSTEM OF SHIELD BACK KATYDIDS (ORTHOPTERA: TETTIGONIIDAE: AGLAOTHORAX): BEHAVIORAL AND PHYLOGENETIC EVIDENCE  

E-Print Network (OSTI)

Sexual selection and species recognition are two processes that may drive evolution of mating systems and contribute to speciation. Evidence from nature is rare. I asked whether song evolution in shield-back katydids (Aglaothorax) from southern...

Cole, Jeffrey A.

2009-12-01T23:59:59.000Z

387

Evolution of parental magmas of Miocene shield basalts of Gran Canaria (Canary Islands): constraints from crystal, melt and fluid inclusions in minerals  

Science Journals Connector (OSTI)

...?Picritic units of the Miocene shield volcanics on Gran Canaria, Canary Islands, contain olivine and clinopyroxene...90-92 were inferred from high-temperature microthermometric quench experiments, low-temperat...

A. A. Gurenko; Thor H. Hansteen

1996-08-01T23:59:59.000Z

388

The Harnessed Atom | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Services » The Harnessed Atom Services » The Harnessed Atom The Harnessed Atom The Harnessed Atom The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on nuclear science and energy. It offers teachers accurate, unbiased, and up-to-date information on the roles that energy and nuclear science play in our lives. The curriculum includes essential principles and fundamental concepts of energy science. This teacher's kit is an updated and expanded edition of the acclaimed 1985 Harnessed Atom curriculum from the U.S. Department of Energy. It was developed with extensive input from classroom teachers across the country in pilot test reviews and workshops, as well as technical reviews from scientists and experts at universities, professional societies, and

389

An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of  

E-Print Network (OSTI)

An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of atomic matter waves. The build-up of atoms in the ground state of a magnetic. We demonstrated a scheme for doing this with Bose condensed atoms [1]. A variable fraction of atoms

390

Stress Corrosion Cracking of the Drip Shield, the Waste Package Outer Barrier, and the Stainless Steel Structural Material  

SciTech Connect

Stress corrosion cracking is one of the most common corrosion-related causes for premature breach of metal structural components. Stress corrosion cracking is the initiation and propagation of cracks in structural components due to three factors that must be present simultaneously: metallurgical susceptibility, critical environment, and static (or sustained) tensile stresses. This report was prepared according to ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]). The purpose of this report is to provide an evaluation of the potential for stress corrosion cracking of the engineered barrier system components (i.e., the drip shield, waste package outer barrier, and waste package stainless steel inner structural cylinder) under exposure conditions consistent with the repository during the regulatory period of 10,000 years after permanent closure. For the drip shield and waste package outer barrier, the critical environment is conservatively taken as any aqueous environment contacting the metal surfaces. Appendix B of this report describes the development of the SCC-relevant seismic crack density model (SCDM). The consequence of a stress corrosion cracking breach of the drip shield, the waste package outer barrier, or the stainless steel inner structural cylinder material is the initiation and propagation of tight, sometimes branching, cracks that might be induced by the combination of an aggressive environment and various tensile stresses that can develop in the drip shields or the waste packages. The Stainless Steel Type 316 inner structural cylinder of the waste package is excluded from the stress corrosion cracking evaluation because the Total System Performance Assessment for License Application (TSPA-LA) does not take credit for the inner cylinder. This document provides a detailed description of the process-level models that can be applied to assess the performance of Alloy 22 (used for the waste package outer barrier) and Titanium Grade 7 (used for the drip shield) that are subjected to the effects of stress corrosion cracking. The use of laser peening or other residual stress mitigation techniques is considered as a means of mitigating stress corrosion cracking in the waste package final closure lid weld.

G. Gordon

2004-10-13T23:59:59.000Z

391

Manhattan Project: Atomic Bombardment, 1932-1938  

Office of Scientific and Technical Information (OSTI)

Solvay Physics Conference, Brussels, October 1933 ATOMIC BOMBARDMENT Solvay Physics Conference, Brussels, October 1933 ATOMIC BOMBARDMENT (1932-1938) Events > Atomic Discoveries, 1890s-1939 A Miniature Solar System, 1890s-1919 Exploring the Atom, 1919-1932 Atomic Bombardment, 1932-1938 The Discovery of Fission, 1938-1939 Fission Comes to America, 1939 M. Stanley Livingston and Ernest O. Lawrence in front of a 27-inch cyclotron, Rad Lab, University of California, Berkeley, 1934. In the 1930s, scientists learned a tremendous amount about the structure of the atom by bombarding it with sub-atomic particles. Ernest O. Lawrence's cyclotron, the Cockroft-Walton machine, and the Van de Graaff generator, developed by Robert J. Van de Graaff at Princeton University, were particle accelerators designed to bombard the nuclei of various elements to disintegrate atoms. Attempts of the early 1930s to split atoms, however, required huge amounts of energy because the first accelerators used proton beams and alpha particles as sources of energy. Since protons and alpha particles are positively charged, they Albert Einstein met substantial resistance from the positively charged target nucleus when they attempted to penetrate atoms. Even high-speed protons and alpha particles scored direct hits on a nucleus only approximately once in a million tries. Most simply passed by the target nucleus. Not surprisingly, Ernest Rutherford, Albert Einstein (right), and Niels Bohr regarded particle bombardment as useful in furthering knowledge of nuclear physics but believed it unlikely to meet public expectations of harnessing the power of the atom for practical purposes anytime in the near future. In a 1933 interview, Rutherford called such expectations "moonshine." Einstein compared particle bombardment with shooting in the dark at scarce birds, while Bohr, the Danish Nobel laureate, agreed that the chances of taming atomic energy were remote.

392

Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory  

SciTech Connect

Since a comb-type rf shield was proposed in 2003 as a rf shield for future high-intensity accelerators, various types of bellow chambers and gate valves with this rf shield have been installed in the KEK B-Factory rings in series and tested with beams. Through beam tests to check the performance, a structural simplification has been tried in parallel. The temperatures of the bellow corrugations decreased by a factor of 3-6 compared to those with a conventional finger-type rf shield in most cases. The temperatures of the body of the gate valves also decreased by a factor of 2-5. These results demonstrated the availability of the comb-type rf shield. Although a discharge was observed in one simplified model, the latest model has shown no problem up to a stored beam current of 1.8 A (1.3 mA/bunch, 6 mm bunch length). Experiences with the comb-type rf shield in these four-year beam tests are reviewed here.

Suetsugu, Yusuke; Kanazawa, Ken-ichi; Shibata, Kyo; Shirai, Mitsuru; Bondar, Aleksander E.; Kuzminykh, Victor S.; Gorbovsky, Aleksander I.; Sonderegger, Kurt; Morii, Minoru; Kawada, Kakuyu [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Budker Institute of Nuclear Physics (BINP), Novosibirsk 630090 (Russian Federation); VAT Vakuumventile AG, Haag CH-9469 (Switzerland); VAT SKK Vacuum Ltd., Yokohama, Kanagawa 240-0023 (Japan)

2007-04-15T23:59:59.000Z

393

Statistical atom: Some quantum improvements  

Science Journals Connector (OSTI)

The Thomas-Fermi model is improved by simultaneously introducing three different quantum corrections. The first concerns the nonlocality of quantum mechanics; we go beyond the von Weizscker approach by including arbitrary powers of the gradient of the single-particle potential. The second is a special treatment of the strongly bound electrons, which removes the incorrect statistical description of the vicinity of the nucleus. In the third we generalize Dirac's way of handling the exchange interaction by, again, including gradient effects to arbitrary order. All this is done in the framework of a "potential-functional method" and results in a new differential equation for the potential. The comparison of numerical results with both experimental and Hartree-Fock data for the mean-squared distance indicates a superiority of the new statistical theory over the Hartree-Fock theory, at least for the description of the outer reaches of the atom.

Berthold-Georg Englert and Julian Schwinger

1984-05-01T23:59:59.000Z

394

Ps-atom scattering at low energies  

E-Print Network (OSTI)

A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $venergy region, in contrast to the inter...

Fabrikant, I I

2015-01-01T23:59:59.000Z

395

Gas Atomization of Stainless Steel - Slow Motion  

SciTech Connect

Stainless steel liquid atomized by supersonic argon gas into a spray of droplets at ~1800C. Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a black and white high speed video of a liquid metal stream being atomized by high pressure gas. This material was atomized at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov

None

2011-01-01T23:59:59.000Z

396

Interfacing ultracold atoms and mechanical oscillators.  

E-Print Network (OSTI)

??In this thesis I present experiments investigating controlled coupling between mechanical oscillators and ultracold atoms. I report on three different coupling mechanisms. In a first (more)

Camerer, Stephan

2011-01-01T23:59:59.000Z

397

Cold collisions of Rb and Cs atoms  

E-Print Network (OSTI)

Jamieson,M.J. Sarbazi-Azad,H. 18'th International Conference on Atomic Physics, MIT, Cambridge, MA, USA Academic Press

Jamieson, M.J.

398

Nonlinear optics with two trapped atoms  

SciTech Connect

We show theoretically that two atomic dipoles in a resonator constitute a nonlinear medium, whose properties can be controlled through the relative position of the atoms inside the cavity and the detuning and intensity of the driving laser. We identify the parameter regime where the system operates as a parametric amplifier, based on the cascade emission of the collective dipole of the atoms, and determine the corresponding spectrum of squeezing of the field at the cavity output. This dynamics might be observed as a result of self-organization of laser-cooled atoms in resonators.

Fernandez-Vidal, Sonia; Zippilli, Stefano [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); ICFO-Institut de Ciencies Fotoniques, E-08860 Castelldefels, Barcelona (Spain); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)

2007-11-15T23:59:59.000Z

399

United States Atomic Energy Commission formed  

NLE Websites -- All DOE Office Websites (Extended Search)

formed As the United Nations Atomic Energy Commission failed to come to grips with the growing nuclear weapons problem, the United States worked to establish its own formal...

400

Atomic Physics and Thermonuclear Fusion Research  

Science Journals Connector (OSTI)

Presently thermonuclear fusion research is faced with a number of atomic and molecular physics problems depending on the type of high-temperature plasma investigated. The present article discusses some particular atomic physics aspects in connection with magnetically confined plasmas (Tokamaks, Stellarators): (1) rate equations for density, momentum and energy with application to plasmas; (2) initial phase of Tokamak plasmas; (3) influence of impurity radiation on operating conditions of fusion plasmas in general and on Tokamak plasmas in particular; (4) influence of atomic elementary reactions on thermodynamic plasma properties; (5) level structures of highly ionized atoms; (6) spectroscopic diagnostic problems.

H W Drawin

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

A History of the Atomic Energy Commission  

Energy.gov (U.S. Department of Energy (DOE))

A History of the Atomic Energy Commission - written by Alice L. BuckWashington, D.C.: U.S. Department of Energy, July 1983.41 pp.

402

Using Atomic Clocks to Detect Gravitational Waves  

E-Print Network (OSTI)

Atomic clocks have recently reached a fractional timing precision of $test masses separated by less than a GW wavelength, currently envisioned for the eLISA mission.

Loeb, Abraham

2015-01-01T23:59:59.000Z

403

Atomic 'mismatch' creates nano 'dumbbells' | Argonne National...  

NLE Websites -- All DOE Office Websites (Extended Search)

Brochures and Reports Summer Science Writing Internship Atomic 'mismatch' creates nano 'dumbbells' By Jared Sagoff * December 4, 2014 Tweet EmailPrint ARGONNE, Ill. - Like...

404

Directly correlated transmission electron microscopy and atom...  

NLE Websites -- All DOE Office Websites (Extended Search)

Directly correlated transmission electron microscopy and atom probe tomography of grain boundary oxidation in a Ni-Al binary Directly correlated transmission electron microscopy...

405

Radiation embrittlement of the neutron shield tank from the Shippingport reactor  

SciTech Connect

The irradiation embrittlement of neutron shield tank (NST) material (A212 Grade B steel) from the Shippingport reactor has been characterized. Irradiation increases the Charpy transition temperature (CTT) by 23--28{degrees}C (41--50{degrees}F) and decreases the upper-shelf energy. The shift in CTT is not as severe as that observed in high-flux isotope reactor (HFIR) surveillance specimens. However, the actual value of the CTT is higher than that for the HFIR data. The increase in yield stress is 51 MPa (7.4 ksi), which is comparable to HFIR data. The NST material is weaker in the transverse orientation than in the longitudinal orientation. Some effects of position across the thickness of the wall are also observed; the CTT shift is slightly greater for specimens from the inner region of the wall. Annealing studies indicate complete recovery from embrittlement after 1 h at 400{degrees}C (752{degrees}F). Although the weld metal is significantly tougher than the base metal, the shifts in CTT are comparable. The shifts in CTT for the Shippingport NST are consistent with the test and Army reactor data for irradiations at <232{degrees}C (<450{degrees}F) and show very good agreement with the results for HFIR A212-B steel irradiated in the Oak Ridge Research Reactor (ORR). The effects of irradiation temperature, fluence rate, and neutron flux spectrum are discussed. The results indicate that fluence rate has no effect on radiation embrittlement at rates as low as 2 {times} 10{sup 8} n/cm{sup 2}{center dot}s and at the low operating temperatures of the Shippingport NST, i.e., 55{degrees}C (130{degrees}F). This suggests that the accelerated embrittlement of HFIR surveillance samples is most likely due to the relatively higher proportion of thermal neutrons in the HFIR spectrum compared to that for the test reactors. 28 refs., 25 figs.

Chopra, O.K.; Shack, W.J. (Argonne National Lab., IL (United States)); Rosinski, S.T. (Sandia National Labs., Albuquerque, NM (United States))

1991-10-01T23:59:59.000Z

406

Optical control of ground-state atomic orbital alignment: Cl,,2 P3/2... atoms  

E-Print Network (OSTI)

Optical control of ground-state atomic orbital alignment: Cl,,2 P3/2... atoms from HCl,,v=2,J=1-of-flight mass spectrometry. The 35 Cl 2 P3/2 atoms are aligned by two mechanisms: 1 the time-dependent transfer is conserved during the photodissociation and thus contributes to the total 35 Cl 2 P3/2 photofragment atomic

Zare, Richard N.

407

Instead of splitting the atom --the  

E-Print Network (OSTI)

the atomic bomb and led to civilian nuclear plants - - ITER seeks to harness nuclear fusion: the power the atomic bomb and led to civilian nuclear plants -- ITER seeks to harness nuclear fusion: the power a few minutes and input/yield ratios remain low. That compares with ITER's goal of producing sustained

408

Chapter 7 - Nanofabrication via atom optics  

Science Journals Connector (OSTI)

Publisher Summary This chapter presents a review of the basic concepts that are used for atomoptical nanofabrication, as well as a discussion of the progress to date in realizations of the techniques. As a new approach to nanofabrication, atom optics offers the possibility of several advantages over existing techniques. For one thing, the fundamental diffraction limit imposed on resolution, present in any process where one attempts to focus particles (whether photons, charged particles, or neutral atoms), can be very small for atoms. Furthermore, atom optics can be used both in a direct deposition mode, where neutral atoms are focused by atom lenses into an extremely fine spot as they deposit onto a substrate, and also in a lithography mode, where focused atoms are used to expose a suitable resist material. In the direct deposition mode, nanostructures can be fabricated in a clean, resist-free environment, with little or no damage to the underlying substrate. Thus, the process can be very localized, with very little scattering and resist penetration. In either mode, parallelism, which is advantageous when issues of fabrication speed and/or long-range spatial coherence are important, can be achieved with very high dimensional accuracy over a large area of the substrate using laser focusing of atoms in a laser interference pattern.

Jabez J. McClelland

2000-01-01T23:59:59.000Z

409

Hartree-Fock theory for pseudorelativistic atoms  

E-Print Network (OSTI)

We study the Hartree-Fock model for pseudorelativistic atoms, that is, atoms where the kinetic energy of the electrons is given by the pseudorelativistic operator \\sqrt{(pc)^2+(mc^2)^2}-mc^2. We prove the existence of a Hartree-Fock minimizer, and prove regularity away from the nucleus and pointwise exponential decay of the corresponding orbitals.

Anna Dall'Acqua; Thomas stergaard Srensen; Edgardo Stockmeyer

2007-07-31T23:59:59.000Z

410

Formation of $??$ atoms in $K_{?4} decay  

E-Print Network (OSTI)

We derive the decay rate of $\\pi\\mu$ atom formation in $K_{\\mu 4}$ decay. Using the obtained expressions we calculate the decay rate of atom formation and point out that considered decay can give a noticeable contribution as a background to the fundamental decay $K^+\\to \\pi^+\

S. R. Gevorkyan; A. V. Tarasov; O. O. Voskresenskaya

2009-12-01T23:59:59.000Z

411

Hydrogen atom moving across a magnetic field  

Science Journals Connector (OSTI)

A hydrogen atom moving across a magnetic field is considered in a wide region of magnitudes of magnetic field and atom momentum. We solve the Schrdinger equation of the system numerically using an imaginary time method and find wave functions of the lowest states of atom. We calculate the energy and the mean electron-nucleus separation as a function of atom momentum and magnetic field. All the results obtained could be summarized as a phase diagram on the atom-momentum magnetic-field plane. There are transformations of wave-function structure at critical values of atom momentum and magnetic field that result in a specific behavior of dependencies of energy and mean interparticle separation on the atom momentum P. We discuss a transition from the Zeeman regime to the high magnetic field regime. A qualitative analysis of the complicated behavior of wave functions vs P based on the effective potential examination is given. We analyze a sharp transition at the critical momentum from a Coulomb-type state polarized due to atom motion to a strongly decentered (Landau-type) state at low magnetic fields. A crossover occurring at intermediate magnetic fields is also studied.

Yu. E. Lozovik and S. Yu. Volkov

2004-08-23T23:59:59.000Z

412

Interaction of trapped ions with trapped atoms  

E-Print Network (OSTI)

In this thesis, I present results from two Paul-trap based ion traps carried out in the Vuleti? laboratory: the Atom-Ion trap for collision studies between cold atoms and cold ions, and the Cavity-Array trap for studying ...

Grier, Andrew T. (Andrew Todd)

2011-01-01T23:59:59.000Z

413

Relativistic atomic physics at the SSC  

SciTech Connect

This report discusses the following proposed work for relativistic atomic physics at the Superconducting Super Collider: Beam diagnostics; atomic physics research; staffing; education; budget information; statement concerning matching funds; description and justification of major items of equipment; statement of current and pending support; and assurance of compliance.

NONE

1990-12-31T23:59:59.000Z

414

New statistical atom: A numerical study  

Science Journals Connector (OSTI)

The new differential equation for the statistical atom is derived and discussed in detail. Numerical results are presented which provide evidence for the validity of all approximations that have entered the formalism. A comparison of experimental data for diamagnetic susceptibilities with theoretical predictions shows that the new statistical atom significantly surpasses its Hartree-Fock competitor.

Berthold-Georg Englert and Julian Schwinger

1984-05-01T23:59:59.000Z

415

Quantum-noise quenching in atomic tweezers  

SciTech Connect

The efficiency of extracting single atoms or molecules from an ultracold bosonic reservoir is theoretically investigated for a protocol based on lasers, coupling the hyperfine state in which the atoms form a condensate to another stable state, in which the atom experiences a tight potential in the regime of collisional blockade, the quantum tweezers. The transfer efficiency into the single-atom ground state of the tight trap is fundamentally limited by the collective modes of the condensate, which are thermally and dynamically excited. The noise due to these excitations can be quenched for sufficiently long laser pulses, thereby achieving high efficiencies. These results show that this protocol can be applied to initializing a quantum register based on tweezer traps for neutral atoms.

Zippilli, Stefano [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); Fachbereich Physik and Research Center OPTIMAS, Technische Universitaet Kaiserslautern, D-67663 Kaiserslautern (Germany); Mohring, Bernd; Schleich, Wolfgang [Institut fuer Quantenphysik, Universitaet Ulm, D-89081 Ulm (Germany); Lutz, Eric [Department of Physics, University of Augsburg, D-86135 Augsburg (Germany); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany)

2011-05-15T23:59:59.000Z

416

Quantum-noise quenching in atomic tweezers  

E-Print Network (OSTI)

The efficiency of extracting single atoms or molecules from an ultracold bosonic reservoir is theoretically investigated for a protocol based on lasers, coupling the hyperfine state in which the atoms form a condensate to another stable state, in which the atom experiences a tight potential in the regime of collisional blockade, the quantum tweezers. The transfer efficiency into the single-atom ground state of the tight trap is fundamentally limited by the collective modes of the condensate, which are thermally and dynamically excited. The noise due to these excitations can be quenched for sufficiently long laser pulses, thereby achieving high efficiencies. These results show that this protocol can be applied for initializing a quantum register based on tweezer traps for neutral atoms.

Stefano Zippilli; Bernd Mohring; Eric Lutz; Giovanna Morigi; Wolfgang Schleich

2011-04-15T23:59:59.000Z

417

Quantum computing with atomic Josephson junction arrays  

SciTech Connect

We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off-resonant optical lattice. Raman lasers provide the 'Josephson' tunneling, and the collision interaction between atoms represent the 'capacitive' couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single-qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

Tian Lin; Zoller, P. [Institute for Theoretical Physics, University of Innsbruck, A-6020 Innsbruck (Austria)

2003-10-01T23:59:59.000Z

418

Quantum Computing with Atomic Josephson Junction Arrays  

E-Print Network (OSTI)

We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off resonant optical lattice. Raman lasers provide the "Josephson" tunneling, and the collision interaction between atoms represent the "capacitive" couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

Lin Tian; P. Zoller

2003-06-12T23:59:59.000Z

419

International Atomic Energy Agency safeguards  

SciTech Connect

The International Atomic Energy Agency (IAEA) is unique among international organizations in its use of on-site inspections to verify that States are in compliance with the terms of a negotiated agreement. The legal basis for the inspections is agreements between the IAEA and the State, concluded in the framework of the Nuclear Nonproliferation Treaty, for full scope safeguards on all nuclear materials. In addition, other more limited agreements for safeguards on a portion of a State's nuclear material are also concluded with States not party to the Treaty. In either case, the role of the IAEA is to verify compliance with the terms of these agreements by auditing facility operating records and reports submitted to the IAEA by the State; by independent measurement of nuclear materials by IAEA inspectors; and by emplacement of surveillance devices to monitor facility operations in the inspector's absence. Although IAEA safeguards are applied only to peaceful nuclear activities and do not attempt to control or reduce the numbers of nuclear weapons, there are aspects of the IAEA methods and technology that may be applicable to treaty verification for arms control. Among these aspects are: (1) the form of the IAEA's agreements with States; (2) the IAEA approach to inspection planning; and (3) the instrumentation employed by the IAEA for monitoring facility activities and for measuring nuclear material.

Avenhaus, R.; Markin, J.

1985-01-01T23:59:59.000Z

420

Magnetic moment of atomic lithium  

Science Journals Connector (OSTI)

Bound-state relativistic contributions to the gJ factor of ground-state atomic lithium are calculated and compared with the experimental value gJ(Li)ge=1-(8.90.4)10-6, where ge is the free-electron g factor. This comparison is taken as the basis for judging the accuracy of several different Li wave functions taken from the literature. Most of these wave functions give agreement with the experimental value within the experimental uncertainty. A more precise experimental measurement would be desirable in order to provide a more stringent test. A wave function of the restricted Hartree-Fock type, however, leads to a value which is in disagreement with the experimental value. This is attributed to the inability of the restricted Hartree-Fock function to account for the exchange polarization of the 1s2 core electrons; the latter are found to contribute about -1.2 10-6 to gJ(Li)ge, or about 13% of the total relativistic correction. In addition to the dominant relativistic corrections of order ?2, radiative corrections (order ?3), and nuclear-mass corrections (order ?2mM) are also calculated. An isotopic shift gJ(Li6)gJ(Li7)=1+3.010-11 is predicted. The experimental measurements for Li are not yet precise enough to test these higher-order corrections.

Roger A. Hegstrom

1975-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Synthesis of zinc oxide particles coated multiwalled carbon nanotubes: Dielectric properties, electromagnetic interference shielding and microwave absorption  

SciTech Connect

Graphical abstract: A resistorcapacitor model could well describe the relationships between the structure and the dielectric properties, electromagnetic interference shielding and microwave-absorption of the composites in the frequency range of 218 GHz. The resonant behavior associated with the multiwalled carbon nanotubes/zinc oxide (MWCNTs/ZnO) interface greatly broadens the absorption band. Highlights: ? ZnO-immobilized on multiwalled carbon nanotubes (MWCNTs/ZnO) have resonant behavior. ? A resistorcapacitor model describes the relation between the structure and properties. ? The composite with 40 wt% MWCNTs/ZnO has good electromagnetic interference shielding. ? Two different types of absorption peaks are found in the MWCNTs/ZnO composites. ? The existence of MWCNTs/ZnO interface broadens the absorption band. -- Abstract: Zinc oxide (ZnO) nanoparticles were coated on the surfaces of multiwalled carbon nanotubes (MWCNTs). High resolution transmission electron microscopy images show that the wurtzite ZnO immobilized on the MWCNTs is single-crystalline with a preferential [0 0 0 2] growth direction. A capacitor was generated by the interface of ZnO and MWCNTs, and a resistorcapacitor model could well describe the relationships between the structure and the dielectric properties, electromagnetic interference shielding and microwave-absorption of the composites in the frequency range of 218 GHz. The network built by ZnO-immobilized MWCNTs could contribute to the improvement of electrical properties. Resonant peaks associated with the capacitor formed by the interface were observed in the microwave absorption spectra, which suggest that reflectionloss peaks greatly broadens the absorption bandwidth.

Song, Wei-Li [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Cao, Mao-Sheng, E-mail: caomaosheng@bit.edu.cn [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Wen, Bo; Hou, Zhi-Ling; Cheng, Jin [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China)] [School of Material Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Yuan, Jie, E-mail: yuanjie4000@sina.com [School of Information Engineering, Central University for Nationality, Beijing 100081 (China)] [School of Information Engineering, Central University for Nationality, Beijing 100081 (China)

2012-07-15T23:59:59.000Z

422

Instrument Series: Microscopy Atom Probe The LEAP  

NLE Websites -- All DOE Office Websites (Extended Search)

Atom Probe Atom Probe The LEAP ® 4000 XHR local electrode atom probe tomography instrument enabled the first- ever comprehensive and accurate 3-D chemical imaging studies of low electrical conductivity materials, such as ceramics, semiconductors and oxides. The LEAP capability is assisting EMSL's efforts to further scientific advancements in interface analysis and microstructural characterization, providing a new tool for understanding the relationship between the nanoscale structure of materials and their macroscopic properties. Research Applications Geochemistry - Studying chemical processes that compose rocks and soils has long been used to determine matter cycles and transport in the environment, which supports critical EMSL research in areas including bioremediation.

423

Nanoscale atomic waveguides with suspended carbon nanotubes  

E-Print Network (OSTI)

We propose an experimentally viable setup for the realization of one-dimensional ultracold atom gases in a nanoscale magnetic waveguide formed by single doubly-clamped suspended carbon nanotubes. We show that all common decoherence and atom loss mechanisms are small guaranteeing a stable operation of the trap. Since the extremely large current densities in carbon nanotubes are spatially homogeneous, our proposed architecture allows to overcome the problem of fragmentation of the atom cloud. Adding a second nanowire allows to create a double-well potential with a moderate tunneling barrier which is desired for tunneling and interference experiments with the advantage of tunneling distances being in the nanometer regime.

V. Peano; M. Thorwart; A. Kasper; R. Egger

2005-11-23T23:59:59.000Z

424

The dressed mobile atoms and ions  

E-Print Network (OSTI)

We consider free atoms and ions in $\\R^3$ interacting with the quantized electromagnetic field. Because of the translation invariance we consider the reduced hamiltonian associated with the total momentum. After introducing an ultraviolet cutoff we prove that the reduced hamiltonian for atoms has a ground state if the coupling constant and the total momentum are sufficiently small. In the case of ions an extra infrared regularization is needed. We also consider the case of the hydrogen atom in a constant magnetic field. Finally we determine the absolutely continuous spectrum of the reduced hamiltonian.

Laurent Amour; Benoit Grebert; Jean-Claude Guillot

2005-07-20T23:59:59.000Z

425

Storing images in warm atomic vapor  

E-Print Network (OSTI)

Reversible and coherent storage of light in atomic medium is a key-stone of future quantum information applications. In this work, arbitrary two-dimensional images are slowed and stored in warm atomic vapor for up to 30 $\\mu$s, utilizing electromagnetically induced transparency. Both the intensity and the phase patterns of the optical field are maintained. The main limitation on the storage resolution and duration is found to be the diffusion of atoms. A techniqueanalogous to phase-shift lithography is employed to diminish the effect of diffusion on the visibility of the reconstructed image.

M. Shuker; O. Firstenberg; R. Pugatch; A. Ron; N. Davidson

2008-06-17T23:59:59.000Z

426

Single atom as a macroscopic entanglement source  

E-Print Network (OSTI)

by many authors including the generation of entangled coherent state #3;1?3#4;, single photon and vacuum entanglement #3;4#4;, and two-atom entanglement #3;5#4;. More recently, generation of macroscopic entangled states via phase sensitive... cascade configuration crossing or trapped in a two-mode field cavity. The atomic level configuration is depicted in Fig. 1. The two atomic transitions #5;a#6;? #5;b#6; and #5;b#6;? #5;c#6; interact with the two cavity modes with detunings #1...

Zhou, Ling; Xiong, Han; Zubairy, M. Suhail.

2006-01-01T23:59:59.000Z

427

Fast Quantum Gates for Neutral Atoms  

Science Journals Connector (OSTI)

We propose several schemes for implementing a fast two-qubit quantum gate for neutral atoms with the gate operation time much faster than the time scales associated with the external motion of the atoms in the trapping potential. In our example, the large interaction energy required to perform fast gate operations is provided by the dipole-dipole interaction of atoms excited to low-lying Rydberg states in constant electric fields. A detailed analysis of imperfections of the gate operation is given.

D. Jaksch; J. I. Cirac; P. Zoller; S. L. Rolston; R. Ct; M. D. Lukin

2000-09-04T23:59:59.000Z

428

Duality in spaces of finite linear combinations of atoms  

E-Print Network (OSTI)

Duality in spaces of finite linear combinations of atoms Fulvio Ricci and Joan Verdera Abstract In this note we describe the dual and the completion of the space of finite linear combinations of (p, )-atoms, )-atoms, 0

Ricci, Fulvio

429

CHARGE TRANSFER BETWEEN POSITIVE ALKALI IONS AND ATOMS  

E-Print Network (OSTI)

average velocity of atoms , ::. : . . :. . in the oven. Thisfor a potassium ", . atom beam operating under conditionsPOSITIVE ALKALI IONS AND ATOMS I W. R. Gentry, Yuan-tseh L e

Gentry, W.R.; Lee, Yuan-tseh; Mahan, Bruce H.

2008-01-01T23:59:59.000Z

430

August 1, 1946: Atomic Energy Act | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

signs the Atomic Energy Act of 1946. On January 1, 1947, all atomic energy activities are transferred to the newly created Atomic Energy Commission in accordance with the Act...

431

Studying coherence in ultra-cold atomic gases  

E-Print Network (OSTI)

This thesis will discuss the study of coherence properties of ultra-cold atomic gases. The atomic systems investigated include a thermal cloud of atoms, a Bose-Einstein condensate and a fermion pair condensate. In each ...

Miller, Daniel E. (Daniel Edward)

2007-01-01T23:59:59.000Z

432

E-Print Network 3.0 - analytical atomic spectroscopy Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

A partial sampling of these techniques includes: Absorption spectroscopy Atomic absorption... spectroscopy Atomic emission spectroscopy Atomic fluorescence...

433

E-Print Network 3.0 - atomic spectroscopy technologies Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

A partial sampling of these techniques includes: Absorption spectroscopy Atomic absorption... spectroscopy Atomic emission spectroscopy Atomic fluorescence...

434

Positronium-atom scattering at low energies  

Science Journals Connector (OSTI)

A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [I. I. Fabrikant and G. F. Gribakin, Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at venergy region, in contrast to the intermediate energy range from the Ps ionization threshold up to v?2 a.u., where the two are similar.

I. I. Fabrikant and G. F. Gribakin

2014-11-20T23:59:59.000Z

435

Testing Lorentz symmetry with atoms and Light  

E-Print Network (OSTI)

This article reports on the Fifth Meeting on CPT and Lorentz Symmetry, CPT'10, held at the end of June 2010 in Bloomington, Indiana, USA. The focus is on recent tests of Lorentz symmetry using atomic and optical physics.

Neil Russell

2011-09-04T23:59:59.000Z

436

Mesic Atoms and the Sigma-Terms  

Science Journals Connector (OSTI)

This talk is intended to be a short round trip through the domains of atomic, nuclear and particle physics. As such, it will be very far from the degree of completeness many of us could wish.

P. M. Gensini

1981-01-01T23:59:59.000Z

437

Electronic transport in atomically thin layered materials  

E-Print Network (OSTI)

Electronic transport in atomically thin layered materials has been a burgeoning field of study since the discovery of isolated single layer graphene in 2004. Graphene, a semi-metal, has a unique gapless Dirac-like band ...

Baugher, Britton William Herbert

2014-01-01T23:59:59.000Z

438

Detecting Topological Phases in Cold Atoms  

E-Print Network (OSTI)

Chern insulators are band insulators which exhibit a gap in the bulk and gapless excitations in the edge. Detection of Chern insulators is a serious challenge in cold atoms since the Hall transport measurements are technically ...

Liu, Xiong-Jun

439

A Magnetic Model of Atomic Constitution  

Science Journals Connector (OSTI)

... to form a perfect analogy to the hypothetical atomic structures. Thus in the case of Boron-10 the central pole contains ten magnets; five of these are "neutralised "by the ...

J. K. MARSH; A. W. STEWART

1922-03-16T23:59:59.000Z

440

Atom-split it for nuclear energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Atom-split it for nuclear energy Fermi-leader of the team that produced the first self-sustaining controlled nuclear chain reaction; contributed to ending WWII Calutron-invented by...

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Colloquium: Artificial gauge potentials for neutral atoms  

SciTech Connect

When a neutral atom moves in a properly designed laser field, its center-of-mass motion may mimic the dynamics of a charged particle in a magnetic field, with the emergence of a Lorentz-like force. In this Colloquium the physical principles at the basis of this artificial (synthetic) magnetism are presented. The corresponding Aharonov-Bohm phase is related to the Berry's phase that emerges when the atom adiabatically follows one of the dressed states of the atom-laser interaction. Some manifestations of artificial magnetism for a cold quantum gas, in particular, in terms of vortex nucleation are discussed. The analysis is then generalized to the simulation of non-Abelian gauge potentials and some striking consequences are presented, such as the emergence of an effective spin-orbit coupling. Both the cases of bulk gases and discrete systems, where atoms are trapped in an optical lattice, are addressed.

Dalibard, Jean; Gerbier, Fabrice; Juzeliunas, Gediminas; Oehberg, Patrik [Laboratoire Kastler Brossel, CNRS, UPMC, Ecole normale superieure, 24 rue Lhomond, 75005, Paris (France); Institute of Theoretical Physics and Astronomy, Vilnius University, A. Gostauto 12, Vilnius 01108 (Lithuania); SUPA, Department of Physics, Heriot-Watt University, Edinburgh, EH14 4AS (United Kingdom)

2011-10-01T23:59:59.000Z

442

The physics of electronic and atomic collisions  

SciTech Connect

This report contains papers on electron, photon, ion, atom, and molecules collisions. Also included are papers from the following symposiums: correlated transfer/excitation and autoionization; collisions with cold particles; collisions involving positrons; and supercomputational collision physics. (LSP)

Dalgarno, A. (Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA)); Freund, R.S. (AT and T Bell Labs., Murray Hill, NJ (USA)); Koch, P.M. (State Univ. of New York, Stony Brook, NY (USA)); Lubell, M.S. (City Coll., New York, NY (USA)); Lucatorto, T.B. (National Inst. of Standards and Technology (NCTL), Gaithersburg, MD (USA)) (eds.)

1990-01-01T23:59:59.000Z

443

Quantum Structures of the Hydrogen Atom  

E-Print Network (OSTI)

Modern quantum theory introduces quantum structures (decompositions into subsystems) as a new discourse that is not fully comparable with the classical-physics counterpart. To this end, so-called Entanglement Relativity appears as a corollary of the universally valid quantum mechanics that can provide for a deeper and more elaborate description of the composite quantum systems. In this paper we employ this new concept to describe the hydrogen atom. We offer a consistent picture of the hydrogen atom as an open quantum system that naturally answers the following important questions: (a) how do the so called "quantum jumps" in atomic excitation and de-excitation occur? and (b) why does the classically and seemingly artificial "center-of-mass + relative degrees of freedom" structure appear as the primarily operable form in most of the experimental reality of atoms?

J. Jeknic-Dugic; M. Dugic; A. Francom; M. Arsenijevic

2014-05-28T23:59:59.000Z

444

SECTION IV: ATOMIC, MOLECULAR AND MATERIALS SCIENCE  

NLE Websites -- All DOE Office Websites (Extended Search)

ATOMIC, MOLECULAR AND MATERIALS SCIENCE A semiempirical scaling law for target K x-ray production in heavy ion collisions... IV-1 R. L. Watson, Y. Peng, V. Horvat, and A....

445

Electrical Analogs of Atomic Radiative Decay Processes  

E-Print Network (OSTI)

Simple electrical circuits are analyzed, and the results show that for high frequencies they have frequency and time responses identical to the spontaneous radiative decays of atoms. As an illustration of the analogy a ...

Fontana, Peter R.; Srivastava, Rajendra P.

1977-03-01T23:59:59.000Z

446

Ab Initio Atomic Simulations of Antisite Pair Recovery in Cubic...  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic Simulations of Antisite Pair Recovery in Cubic Silicon Carbide. Ab Initio Atomic Simulations of Antisite Pair Recovery in Cubic Silicon Carbide. Abstract: The thermal...

447

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution...  

NLE Websites -- All DOE Office Websites (Extended Search)

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Abstract:...

448

LSU EFRC - Center for Atomic Level Catalyst Design - About Us  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysis and Atomic-Level Synthesis" The mission of LSU's Center for Atomic Level Catalyst Design is to advance: the ability of computational methods to accurately model...

449

LSU EFRC - Center for Atomic Level Catalyst Design  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysis and Atomic-Level Synthesis" The mission of LSU's Center for Atomic Level Catalyst Design is to advance: the ability of computational methods to accurately model...

450

2nd conference on Intense field- Short Wavelength Atomic and...  

NLE Websites -- All DOE Office Websites (Extended Search)

nd conference on Intense field- Short Wavelength Atomic and Molecular Processes - ISWAMP2 2nd conference on Intense field- Short Wavelength Atomic and Molecular Processes - ISWAMP2...

451

Single Supported Atoms Participate in Catalytic Processes | ornl...  

NLE Websites -- All DOE Office Websites (Extended Search)

Functional Materials for Energy Single Supported Atoms Participate in Catalytic Processes December 04, 2014 Pathways for NO oxidation on single Pt atoms supported on the (010)...

452

Loading rubidium atoms into a hollow core fiber .  

E-Print Network (OSTI)

??We demonstrate a procedure for cooling, trapping, and transferring rubidium atoms into a hollow core photonic band gap fiber. The atoms are first collected in (more)

Chu, Yiwen

2007-01-01T23:59:59.000Z

453

DOE - Office of Legacy Management -- Knolls Atomic Power Laboratory...  

Office of Legacy Management (LM)

Knolls Atomic Power Laboratory - NY 16 FUSRAP Considered Sites Site: Knolls Atomic Power Laboratory (NY.16) Designated Name: Alternate Name: Location: Evaluation Year: Site...

454

Institute for Atom-Efficient Chemical Transformations Energy...  

NLE Websites -- All DOE Office Websites (Extended Search)

Institute for Atom-Efficient Chemical Transformations - an Energy Frontier Research Center The Institute for Atom-Efficient Chemical Transformations (IACT) employs a...

455

Isolation, Characterization of an Intermediate in an Oxygen Atom...  

NLE Websites -- All DOE Office Websites (Extended Search)

Characterization of an Intermediate in an Oxygen Atom-Transfer Reaction, and the Determination of the Bond Isolation, Characterization of an Intermediate in an Oxygen Atom-Transfer...

456

Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions...  

National Nuclear Security Administration (NNSA)

Our Jobs Working at NNSA Blog Home About Us Our History NNSA Timeline Atomic Energy Commission Explores Peaceful Uses of ... Atomic Energy Commission Explores Peaceful...

457

Contribution of atom-probe tomography to a better understanding...  

NLE Websites -- All DOE Office Websites (Extended Search)

atom-probe tomography to a better understanding of glass alteration mechanisms: application to a nuclear glass Contribution of atom-probe tomography to a better understanding of...

458

Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of AlZn  

E-Print Network (OSTI)

Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of Al-block main group element, aluminum, and the 3d series of transi- tion metal atoms. Although the bonding in Al

Morse, Michael D.

459

Spectrally controlled atom-by-atom photoassembly of silver clusters on the surface of ionic-covalent crystals  

Science Journals Connector (OSTI)

The fundamental possibility of implementing light-controlled atom-by-atom assembly of silver clusters beginning with dimers and trimers via photostimulated diffusion of individual atoms initially adsorbed on t...

A. N. Latyshev; O. V. Ovchinnikov; M. S. Smirnov

2010-11-01T23:59:59.000Z

460

Study on reduction in electric field, charged voltage, ion current and ion density under HVDC transmission lines by parallel shield wires  

SciTech Connect

An important problem in the design and operation of HVDC transmission lines is to reduce electrical field effects such as ion flow electrification of objects, electric field, ion current and ion density at ground level in the vicinity of HVDC lines. Several models of shield wire were tested with the Shiobara HVDC test line. The models contain typical stranded wires that are generally used to reduce field effects at ground level, neutral conductors placed at lower parts of the DC line, and an ''earth corona model'' to cancel positive or negative ions intentionally by generating ions having opposite polarity to ions flowing into the wire. This report describes the experimental results of the effects of these shield wires and a method to predict shielding effects.

Amano, Y.; Sunaga, Y.

1989-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Neutrino Spectroscopy with Atoms and Molecules  

E-Print Network (OSTI)

We give a comprehensive account of our proposed experimental method of using atoms or molecules in order to measure parameters of neutrinos still undetermined; the absolute mass scale, the mass hierarchy pattern (normal or inverted), the neutrino mass type (Majorana or Dirac), and the CP violating phases including Majorana phases. There are advantages of atomic targets, due to the closeness of available atomic energies to anticipated neutrino masses, over nuclear target experiments. Disadvantage of using atomic targets, the smallness of rates, is overcome by the macro-coherent amplification mechanism. The atomic or molecular process we use is a cooperative deexcitation of a collective body of atoms in a metastable level |e> emitting a neutrino pair and a photon; |e> -> |g> + gamma + nu_i nu_j where nu_i's are neutrino mass eigenstates. The macro-coherence is developed by trigger laser irradiation. We discuss aspects of the macro-coherence development by setting up the master equation for the target quantum state and propagating electric field. With a choice of heavy target atom or molecule such as Xe or I_2 that has a large M1 x E1 matrix element between |e> and |g>, we show that one can determine three neutrino masses along with the mass hierarchy pattern by measuring the photon spectral shape. If one uses a target of available energy of a fraction of 1 eV, Majorana CP phases may be determined. Our master equation, when applied to E1 x E1 transition such as pH_2 vibrational transition Xv=1 -> 0, can describe explosive PSR events in which most of the energy stored in |e> is released within a few nanoseconds. The present paper is intended to be self-contained explaining some details related theoretical works in the past, and further reports new simulations and our ongoing experimental efforts of the project to realize the neutrino mass spectroscopy using atoms/molecules.

Atsushi Fukumi; Susumu Kuma; Yuki Miyamoto; Kyo Nakajima; Itsuo Nakano; Hajime Nanjo; Chiaki Ohae; Noboru Sasao; Minoru Tanaka; Takashi Taniguchi; Satoshi Uetake; Tomonari Wakabayashi; Takuya Yamaguchi; Akihiro Yoshimi; Motohiko Yoshimura

2012-11-21T23:59:59.000Z

462

Production of mesoscopic superpositions with ultracold atoms  

E-Print Network (OSTI)

We study mesoscopic superpositions of two component Bose-Einstein condensates. Atomic condensates, with long coherence times, are good systems in which to study such quantum phenomenon. We show that the mesoscopic superposition states can be rapidly generated in which the atoms dispersively interact with the photon field in a cavity. We also discuss the production of compass states which are generalized Schr\\"{o}dinger cat states. The physical realization of mesoscopic states is important in studying decoherence and precision measurement.

H. T. Ng

2007-07-16T23:59:59.000Z

463

Atomization of metal (Materials Preparation Center)  

SciTech Connect

Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a color video of a liquid metal stream being atomized by high pressure gas. This material was cast at the Ames Laboratorys Materials Preparation Center http://www.mpc.ameslab.gov WARNING - AUDIO IS LOUD.

None

2010-01-01T23:59:59.000Z

464

Kinetics of atoms in a bichromatic field  

SciTech Connect

The kinetics of atoms in a bichromatic field is considered. Analytic solutions are obtained for the force, friction coefficient, and diffusion coefficient in the model of a two-level atom without limitations imposed on the intensity of light fields. This effect is observed in the domain of global minima and maxima of the optical potential (i.e., at points where the relative phase of two standing waves is Greek-Phi-Symbol = 0, {pi}/2.

Prudnikov, O. N., E-mail: llf@laser.nsc.ru [Novosibirsk State University (Russian Federation); Baklanov, A. S. [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation)] [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation); Taichenachev, A. V. [Novosibirsk State University (Russian Federation)] [Novosibirsk State University (Russian Federation); Tumaikin, A. M. [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation)] [Russian Academy of Sciences, Institute of Laser Physics, Siberian Branch (Russian Federation); Yudin, V. I. [Novosibirsk State University (Russian Federation)] [Novosibirsk State University (Russian Federation)

2013-08-15T23:59:59.000Z

465

Atomic resolution images of graphite in air  

SciTech Connect

One sample used for proof of operation for atomic resolution in STM is highly oriented pyrolytic graphite (HOPG). This sample has been imaged with many different STM`s obtaining similar results. Atomic resolution images of HOPG have now been obtained using an STM designed and built at the Precision Engineering Center. This paper discusses the theoretical predictions and experimental results obtained in imaging of HOPG.

Grigg, D.A.; Shedd, G.M.; Griffis, D.; Russell, P.E.

1988-12-01T23:59:59.000Z

466

Hydrogen atom in rotationally invariant noncommutative space  

E-Print Network (OSTI)

We consider the noncommutative algebra which is rotationally invariant. The hydrogen atom is studied in a rotationally invariant noncommutative space. We find the corrections to the energy levels of the hydrogen atom up to the second order in the parameter of noncommutativity. The upper bound of the parameter of noncommutativity is estimated on the basis of the experimental results for 1s-2s transition frequency.

Kh. P. Gnatenko; V. M. Tkachuk

2014-11-03T23:59:59.000Z

467

Spatially resolved excitation of Rydberg atoms and surface effects on an atom chip  

SciTech Connect

We demonstrate spatially resolved, coherent excitation of Rydberg atoms on an atom chip. Electromagnetically induced transparency (EIT) is used to investigate the properties of the Rydberg atoms near the gold-coated chip surface. We measure distance-dependent shifts ({approx}10 MHz) of the Rydberg energy levels caused by a spatially inhomogeneous electric field. The measured field strength and distance dependence is in agreement with a simple model for the electric field produced by a localized patch of Rb adsorbates deposited on the chip surface during experiments. The EIT resonances remain narrow (<4 MHz) and the observed widths are independent of atom-surface distance down to {approx} 20 {mu}m, indicating relatively long lifetime of the Rydberg states. Our results open the way to studies of dipolar physics, collective excitations, quantum metrology, and quantum information processing involving interacting Rydberg excited atoms on atom chips.

Tauschinsky, Atreju; Thijssen, Rutger M. T.; Whitlock, S.; Linden van den Heuvell, H. B. van; Spreeuw, R. J. C. [Van der Waals-Zeeman Institute, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)

2010-06-15T23:59:59.000Z

468

Excess optical quantum noise in atomic sensors  

E-Print Network (OSTI)

Enhanced nonlinear optical response of a coherent atomic medium is the basis for many atomic sensors, and their performance is ultimately limited by the quantum fluctuations of the optical read-out. Here we demonstrate that off-resonant interactions can significantly modify the quantum noise of the optical field, even when their effect on the mean signal is negligible. We illustrate this concept by using an atomic magnetometer based on the nonlinear Faraday effect: the rotation of the light polarization is mainly determined by the resonant light-induced spin alignment, which alone does not change the photon statistics of the optical probe. Yet, we found that the minimum noise of output polarization rotation measurements is above the expected shot noise limit. This excess quantum noise is due to off-resonant coupling and grows with atomic density. We also show that the detection scheme can be modified to reduce the measured quantum noise (even below the shot-noise limit) but only at the expense of the reduced rotational sensitivity. These results show the existence of previously unnoticed factors in fundamental limitations in atomic magnetometry and could have impacts in many other atom-light based precision measurements.

Irina Novikova; Eugeniy E. Mikhailov; Yanhong Xiao

2014-10-14T23:59:59.000Z

469

From Lattice Gauge Theories to Hydrogen Atoms  

E-Print Network (OSTI)

Using canonical transformations we obtain a complete and most economical realization of the loop or physical Hilbert space of pure $SU(2)_{2+1}$ lattice gauge theory in terms of Wigner coupled Hilbert spaces of hydrogen atoms. One hydrogen atom is assigned to every plaquette of the lattice. The SU(2) gauge theory loop basis states over a plaquette are the bound energy eigenstates $|n l m>$ of the corresponding hydrogen atom. The Wigner couplings of these hydrogen atom energy eigenstates on different plaquettes provide a complete SU(2) gauge theory loop basis on the entire lattice. The loop basis is invariant under simultaneous rotations of all hydrogen atoms. The dual description of this basis diagonalizes all Wilson loop operators and is given in terms of hyperspherical harmonics on the SU(2) group manifold $S^3$. The SU(2) loop dynamics is governed by a "SU(2) spin Hamiltonian" without any gauge fields. The relevance of the hydrogen atom basis and its dynamical symmetry group SO(4,2) in SU(2) loop dynamics in weak coupling continuum limit ($g^2\\rightarrow 0$) is emphasized.

Manu Mathur; T. P. Sreeraj

2014-10-13T23:59:59.000Z

470

Cavity cooling of an atomic array  

E-Print Network (OSTI)

While cavity cooling of a single trapped emitter was demonstrated, cooling of many particles in an array of harmonic traps needs investigation and poses a question of scalability. This work investigates the cooling of a one dimensional atomic array to the ground state of motion via the interaction with the single mode field of a high-finesse cavity. The key factor ensuring the cooling is found to be the mechanical inhomogeneity of the traps. Furthermore it is shown that the pumped cavity mode does not only mediate the cooling but also provides the necessary inhomogeneity if its periodicity differs from the one of the array. This configuration results in the ground state cooling of several tens of atoms within a few milliseconds, a timescale compatible with current experimental conditions. Moreover, the cooling rate scaling with the atom number reveals a drastic change of the dynamics with the size of the array: atoms are either cooled independently, or via collective modes. In the latter case the cavity mediated atom interaction destructively slows down the cooling as well as increases the mean occupation number, quadratically with the atom number. Finally, an order of magnitude speed up of the cooling is predicted as an outcome the optimization scheme based on the adjustment of the array versus the cavity mode periodicity.

Oxana Mishina

2014-04-16T23:59:59.000Z

471

Analytical quality control services of the International Atomic Energy Agency  

Science Journals Connector (OSTI)

The International Atomic Energy Agency provides quality control services to analytical laboratories. These services...

O. Suschny

1986-01-01T23:59:59.000Z

472

Parent--daughter system: D Number of daughter atoms, today  

E-Print Network (OSTI)

- t ) + # , - #12;) . Parent--daughter system: D = N0 ­N D ­ Number of daughter atoms, today N ­ Number of parent atoms, today N0 ­ Number of parent atoms, initially present N0 = D + N, hence: D + N = Net , or D = N et as atoms are transferred from the liquid melt to the solid crystal. Some of the elements incorporated

Siebel, Wolfgang

473

Towards new states of matter with atoms and photons  

E-Print Network (OSTI)

Towards new states of matter with atoms and photons Jonas Larson Stockholm University and Universität zu Köln Aarhus "Cold atoms and beyond" 26/6-2014 #12;Motivation Optical lattices + control QED = coupling between few material (atomic) and few electromagnetic degrees of freedom. Cavity atom

474

Publication of New Atomic Bomb Radiation Dosimetry System  

Energy.gov (U.S. Department of Energy (DOE))

Atomic bomb dosimetry studies. The Radiation Effects Research Foundation Dosimetry System 2002 (DS02)

475

5 1 Danish Atomic Energy Commission 3 Research Establishment Ris  

E-Print Network (OSTI)

SK S I§ 5 1 Danish Atomic Energy Commission 3 § Research Establishment Risø Risø Report No. 249 P u on Luminescence Dosimetry The Danish Atomic Energy Commission Research Establishment KisS October 11-14 1 971 Sponsored by The Danish Atomic Energy Commission and International Atomic Energy Agency Editor V. Mejdahl

476

PC-ATOMIC Final Report 1 Joseph D. Touch1  

E-Print Network (OSTI)

. This document describes the PC-ATOMIC interface, its design, capabilities, and performance. The board design@isi.edu ABSTRACT: PC-ATOMIC is a PC interface for the ATOMIC LAN. PC- ATOMIC is implemented as a VL-Bus (VESA) short-form card for Intel i486 PCs, providing an interface for low-cost workstations to a 640 Mbps LAN

Touch, Joe

477

Precision Calculations of Atoms with Few Valence Electrons  

E-Print Network (OSTI)

Precision Calculations of Atoms with Few Valence Electrons M. G. KOZLOV Petersburg Nuclear Physics words: atoms; effective Hamiltonian; pair equations; precision calculation; valence electron for valence electrons of an atom. The low-energy part of atomic spectrum is found by solving the eigenvalue

Kozlov, Mikhail G

478

Precision Calculations of Atoms with Few Valence Electrons  

E-Print Network (OSTI)

Precision Calculations of Atoms with Few Valence Electrons M. G. KOZLOV Petersburg Nuclear Physics for valence electrons of an atom. The low-energy part of atomic spectrum is found by solving the eigenvalue­valence correlations. We tested this method on a toy model of a four-electron atom with the core 1s2 . The spectrum

Kozlov, Mikhail G

479

Toward improved photon-atom scattering predictions  

SciTech Connect

Photon-atom scattering is important in a variety of applications, but scattering from a composite system depends on the accurate characterization of the scattering from an isolated atom or ion. We have been examining the validity of simpler approximations of elastic scattering in the light of second-order S-matrix theory. Partitioning the many-body amplitude into Rayleigh and Delbrueck components, processes beyond photoionization contribute. Subtracted cross sections for bound-bound atomic transitions, bound pair annihilation, and bound pair production are required in anomalous scattering factors for: (1) convergence of the dispersion integral; (2) agreement with predictions of the more sophisticated S-matrix approach; (3) satisfying the Thomas-Reiche-Kuhn sum rule. New accurate tabulations of anomalous scattering factors have been prepared for all Z, for energies 0--10,000 keV, within the independent particle approximation (IPA) using a Dirac-Slater model of the atom. Separately, experimental atomic photoabsorption threshold information has been used to modify these IPA predictions for improved comparison with experiment.

Kissel, L.

1994-10-21T23:59:59.000Z

480

An Atomic Gravitational Wave Interferometric Sensor (AGIS)  

SciTech Connect

We propose two distinct atom interferometer gravitational wave detectors, one terrestrial and another satellite-based, utilizing the core technology of the Stanford 10m atom interferometer presently under construction. Each configuration compares two widely separated atom interferometers run using common lasers. The signal scales with the distance between the interferometers, which can be large since only the light travels over this distance, not the atoms. The terrestrial experiment with baseline {approx} 1 km can operate with strain sensitivity {approx} 10{sup -19}/{radical}Hz in the 1 Hz-10 Hz band, inaccessible to LIGO, and can detect gravitational waves from solar mass binaries out to megaparsec distances. The satellite experiment with baseline {approx} 1000 km can probe the same frequency spectrum as LISA with comparable strain sensitivity {approx} 10{sup -20}/{radical}Hz. The use of ballistic atoms (instead of mirrors) as inertial test masses improves systematics coming from vibrations, acceleration noise, and significantly reduces spacecraft control requirements. We analyze the backgrounds in this configuration and discuss methods for controlling them to the required levels.

Dimopoulos, Savas; /Stanford U., Phys. Dept.; Graham, Peter W.; /SLAC; Hogan, Jason M.; Kasevich, Mark A.; /Stanford U., Phys. Dept.; Rajendran, Surjeet; /SLAC /Stanford U., Phys. Dept.

2008-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "duncan atomic shield" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Hydrogen atom in de Sitter spaces  

E-Print Network (OSTI)

The hydrogen atom theory is developed for the de Sitter and anti de Sitter spaces on the basis of the Klein-Gordon-Fock wave equation in static coordinates. In both models, after separation of the variables, the problem is reduced to the general Heun equation, a second order linear differential equation having four regular singular points. A qualitative examination shows that the energy spectrum for the hydrogen atom in the de Sitter space should be quasi-stationary, and the atom should be unstable. We derive an approximate expression for energy levels within the quasi-classical approach and estimate the probability of decay of the atom. A similar analysis shows that in the anti de Sitter model the hydrogen atom should be stable in the quantum-mechanical sense. Using the quasi-classical approach, we derive approximate formulas for energy levels for this case as well. Finally, we present the extension to the case of a spin 1/2 particle for both de Sitter models. This extension leads to complicated differential equations with 8 singular points.

O. V. Veko; K. V. Kazmerchuk; E. M. Ovsiyuk; V. M. Red'kov; A. M. Ishkhanyan

2014-12-28T23:59:59.000Z

482

Method and apparatus for atomic imaging  

DOE Patents (OSTI)

A method and apparatus for three dimensional imaging of the atomic environment of disordered adsorbate atoms are disclosed. The method includes detecting and measuring the intensity of a diffuse low energy electron diffraction pattern formed by directing a beam of low energy electrons against the surface of a crystal. Data corresponding to reconstructed amplitudes of a wave form is generated by operating on the intensity data. The data corresponding to the reconstructed amplitudes is capable of being displayed as a three dimensional image of an adsorbate atom. The apparatus includes a source of a beam of low energy electrons and a detector for detecting the intensity distribution of a DLEED pattern formed at the detector when the beam of low energy electrons is directed onto the surface of a crystal. A device responsive to the intensity distribution generates a signal corresponding to the distribution which represents a reconstructed amplitude of a wave form and is capable of being converted into a three dimensional image of the atomic environment of an adsorbate atom on the crystal surface.

Saldin, Dilano K. (Milwaukee, WI); de Andres Rodriquez, Pedro L. (Madrid, ES)

1993-01-01T23:59:59.000Z

483

ANL/APS/TB-44, Guidelines for Beamline and Front-End Radiation Shielding Design at the Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

APS/TB-44 Rev. 4 APS/TB-44 Rev. 4 Guidelines for Beamline and Front-End Radiation Shielding Design at the Advanced Photon Source Revision 4 Advanced Photon Source About Argonne National Laboratory Argonne is a U.S. Department of Energy laboratory managed by UChicago Argonne, LLC under contract DE-AC02-06CH11357. The Laboratory's main facility is outside Chicago, at 9700 South Cass Avenue, Argonne, Illinois 60439. For information about Argonne and its pioneering science and technology programs, see www.anl.gov. Availability of This Report This report is available, at no cost, at http://www.osti.gov/bridge. It is also available on paper to the U.S. Department of Energy and its contractors, for a processing fee, from: U.S. Department of Energy Office of Scientific and Technical Information

484

Identification of Unknown Interface Locations in a Source/Shield System Using the Mesh Adaptive Direct Search Method  

SciTech Connect

The Levenberg-Marquardt (or simply Marquardt) and differential evolution (DE) optimization methods were recently applied to solve inverse transport problems. The Marquardt method is fast but convergence of the method is dependent on the initial guess. While it has been shown to work extremely well at finding an optimum independent of the initial guess, the DE method does not provide a global optimal solution in some problems. In this paper, we apply the Mesh Adaptive Direct Search (MADS) algorithm to solve the inverse problem of material interface location identification in one-dimensional spherical radiation source/shield systems, and we compare the results obtained by MADS to those obtained by Levenberg-Marquardt and DE.

Armstrong, Jerawan C. [Los Alamos National Laboratory; Favorite, Jeffrey A. [Los Alamos National Laboratory

2012-06-20T23:59:59.000Z

485

Influence of the electron-exchange and quantum shielding on the bremsstrahlung spectrum in degenerate quantum plasmas  

SciTech Connect

The influence of the electron-exchange and quantum shielding on the bremsstrahlung spectrum is investigated in degenerate quantum plasmas. The impact-parameter analysis with the Shukla-Eliasson potential is applied to obtain the electron-ion bremsstrahlung radiation cross section as a function of the impact parameter, photon energy, projectile energy, electron-exchange parameter, Fermi energy, and plasmon energy. The result shows that the electron-exchange effect strongly enhances the bremsstrahlung radiation spectrum in degenerate quantum plasmas. It is also shown that the influence of the electron-exchange broadens the photon emission range in the electron-ion bremsstrahlung process. It is found that the electron-exchange effect focuses the bremsstrahlung photon energy in the soft photon domain. In addition, it is found that the bremsstrahlung radiation cross section increases with an increase of the Fermi energy and, however, decreases with increasing plasmon energy.

Jung, Young-Dae [Department of Electrical and Computer Engineering, MC 0407, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0407, USA and Department of Applied Physics, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of)] [Department of Electrical and Computer Engineering, MC 0407, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0407, USA and Department of Applied Physics, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of)

2013-10-15T23:59:59.000Z

486

Constraints on the motions of South American and African Shields during the Proterozoic: I. 40Ar/39Ar and paleomagnetic correlations between Venezuela and Liberia  

Science Journals Connector (OSTI)

...PROTEROZOIC SOUTH AMERICAN AND AFRICAN SHIELDS 1049 TABLE 2. (Continued) T( C) f, Atmos. (%) ." Ar (x lO _ 6 cm 3 STPg) f(39) " A r / * > A r Age (Ma)* Sample Bio ON33 508 0.0000 -0.0000 39 1.28 0.003 0.00 1,358 53 550 -0...

487

{sup 33}S hyperfine interactions in H{sub 2}S and SO{sub 2} and revision of the sulfur nuclear magnetic shielding scale  

SciTech Connect

Using the Lamb-dip technique, the hyperfine structure in the rotational spectra of H{sub 2}{sup 33}S and {sup 33}SO{sub 2} has been resolved and the corresponding parametersthat is, the sulfur quadrupole-coupling and spinrotation tensorswere determined. The experimental parameters are in good agreement with results from high-level coupled-cluster calculations, provided that up to quadruple excitations are considered in the cluster operator, sufficiently large basis sets are used, and vibrational corrections are accounted for. The {sup 33}S spin-rotation tensor for H{sub 2}S has been used to establish a new sulfur nuclear magnetic shielding scale, combining the paramagnetic part of the shielding as obtained from the spinrotation tensor with a calculated value for the diamagnetic part as well as computed vibrational and temperature corrections. The value of 716(5)ppm obtained in this way for the sulfur shielding of H{sub 2}S is in good agreement with results from high-accuracy quantum-chemical calculations but leads to a shielding scale that is about 28ppm lower than the one suggested previously in the literature, based on the {sup 33}S spin-rotation constant of OCS.

Helgaker, Trygve, E-mail: t.u.helgaker@kjemi.uio.no [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, N-0315 Oslo (Norway)] [Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, N-0315 Oslo (Norway); Gauss, Jrgen, E-mail: gauss@uni-mainz.de [Institut fr Physikalische Chemie, Universitt Mainz, D-55099 Mainz (Germany)] [Institut fr Physikalische Chemie, Universitt Mainz, D-55099 Mainz (Germany); Cazzoli, Gabriele, E-mail: gabriele.cazzoli@unibo.it; Puzzarini, Cristina, E-mail: cristina.puzzarini@unibo.it [Dipartimento di Chimica Giacomo Ciamician, Universit di Bologna, Via Selmi 2, I-40126 Bologna (Italy)] [Dipartimento di Chimica Giacomo Ciamician, Universit di Bologna, Via Selmi 2, I-40126 Bologna (Italy)

2013-12-28T23:59:59.000Z

488

Spectroscopy and atomic force microscopy of biomass  

NLE Websites -- All DOE Office Websites (Extended Search)

Spectroscopy Spectroscopy and atomic force microscopy of biomass L. Tetard a,b , A. Passian a,b,n , R.H. Farahi a , U.C. Kalluri c , B.H. Davison c , T. Thundat a,b a Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA b Department of Physics, University of Tennessee, Knoxville, TN 37996, USA c Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA a r t i c l e i n f o Keywords: Atomic force microscopy Spectroscopy Plant cells Biomass Nanomechanics a b s t r a c t Scanning probe microscopy has emerged as a powerful approach to a broader understanding of the molecular architecture of cell walls, which may shed light on the challenge of efficient cellulosic ethanol production. We have obtained preliminary images of both Populus and switchgrass samples using atomic force microscopy (AFM). The results show distinctive features that are shared by switchgrass

489

Standard Model tests with trapped radioactive atoms  

E-Print Network (OSTI)

We review the use of laser cooling and trapping for Standard Model tests, focusing on trapping of radioactive isotopes. Experiments with neutral atoms trapped with modern laser cooling techniques are testing several basic predictions of electroweak unification. For nuclear $\\beta$ decay, demonstrated trap techniques include neutrino momentum measurements from beta-recoil coincidences, along with methods to produce highly polarized samples. These techniques have set the best general constraints on non-Standard Model scalar interactions in the first generation of particles. They also have the promise to test whether parity symmetry is maximally violated, to search for tensor interactions, and to search for new sources of time reversal violation. There are also possibilites for exotic particle searches. Measurements of the strength of the weak neutral current can be assisted by precision atomic experiments using traps of small numbers of radioactive atoms, and sensitivity to possible time-reversal violating electric dipole moments can be improved.

J. A. Behr; G. Gwinner

2009-03-04T23:59:59.000Z

490

Observables in Neutrino Mass Spectroscopy Using Atoms  

E-Print Network (OSTI)

The process of collective de-excitation of atoms in a metastable level into emission mode of a single photon plus a neutrino pair, called radiative emission of neutrino pair (RENP), is sensitive to the absolute neutrino mass scale, to the neutrino mass hierarchy and to the nature (Dirac or Majorana) of massive neutrinos. We investigate how the indicated neutrino mass and mixing observables can be determined from the measurement of the corresponding continuous photon spectrum taking the example of a transition between specific levels of the Yb atom. The possibility of determining the nature of massive neutrinos and, if neutrinos are Majorana fermions, of obtaining information about the Majorana phases in the neutrino mixing matrix, is analyzed in the cases of normal hierarchical, inverted hierarchical and quasi-degenerate types of neutrino mass spectrum. We find, in particular, that the sensitivity to the nature of massive neutrinos depends critically on the atomic level energy difference relevant in the RENP.

D. N. Dinh; S. T. Petcov; N. Sasao; M. Tanaka; M. Yoshimura

2012-09-21T23:59:59.000Z

491

Conservation laws and laser cooling of atoms  

E-Print Network (OSTI)

The straightforward application of energy and linear momentum conservation to the absorption/emission of photons by atoms--first outlined by Schr\\"odinger in 1922--allows to establish the essential features of laser cooling of two levels atoms at low laser intensities. The minimum attainable average kinetic energy of the atoms depends on the ratio $\\Gamma/E_R$ between the natural linewidth and the recoil energy and tends to $E_R$ as $\\Gamma/E_R$ tends to zero. This treatment is valid for any value of the ratio $\\Gamma/E_R$ and contains the semiclassical theory of laser cooling as the limiting case in which $E_R\\ll \\Gamma$.

Giuliani, Giuseppe

2015-01-01T23:59:59.000Z

492

Effects of a uniform acceleration on atom-field interactions  

E-Print Network (OSTI)

We review some quantum electrodynamical effects related to the uniform acceleration of atoms in vacuum. After discussing the energy level shifts of a uniformly accelerated atom in vacuum, we investigate the atom-wall Casimir-Polder force for accelerated atoms, and the van der Waals/Casimir-Polder interaction between two accelerated atoms. The possibility of detecting the Unruh effect through these phenomena is also discussed in detail.

Jamir Marino; Antonio Noto; Roberto Passante; Lucia Rizzuto; Salvatore Spagnolo

2014-04-09T23:59:59.000Z

493

Optical pumping of a lithium atomic beam for atom interferometry J. Gillot, A. Gauguet, M. Buchner, and J. Vigue  

E-Print Network (OSTI)

Optical pumping of a lithium atomic beam for atom interferometry J. Gillot, A. Gauguet, M. B.vigue@irsamc.ups-tlse.fr (Dated: May 29, 2013) We apply optical pumping to prepare the lithium beam of our atom interferometer in a single hyperfine-Zeeman sublevel: we use two components of the D1-line for pumping the 7 Li atoms

Paris-Sud XI, Université de

494

Concepts and Tests for the Remote-Controlled Dismantling of the Biological Shield and Form work of the KNK Reactor - 13425  

SciTech Connect

The compact sodium-cooled nuclear reactor facility Karlsruhe (KNK), a prototype Fast Breeder, is currently in an advanced stage of dismantling. Complete dismantling is based on 10 partial licensing steps. In the frame of the 9. decommissioning permit, which is currently ongoing, the dismantling of the biological shield is foreseen. The biological shield consists of heavy reinforced concrete with built-in steel fitments, such as form-work of the reactor tank, pipe sleeves, ventilation channels, and measuring devices. Due to the activation of the inner part of the biological shield, dismantling has to be done remote-controlled. During a comprehensive basic design phase a practical dismantling strategy was developed. Necessary equipment and tools were defined. Preliminary tests revealed that hot wire plasma cutting is the most favorable cutting technology due to the geometrical boundary conditions, the varying distance between cutter and material, and the heavy concrete behind the steel form-work. The cutting devices will be operated remotely via a carrier system with an industrial manipulator. The carrier system has expandable claws to adjust to the varying diameter of the reactor shaft during dismantling progress. For design approval of this prototype development, interaction between manipulator and hot wire plasma cutting was tested in a real configuration. For the demolition of the concrete structure, an excavator with appropriate tools, such as a hydraulic hammer, was selected. Other mechanical cutting devices, such as a grinder or rope saw, were eliminated because of concrete containing steel spheres added to increase the shielding factor of the heavy concrete. Dismantling of the biological shield will be done in a ring-wise manner due to static reasons. During the demolition process, the excavator is positioned on its tripod in three concrete recesses made prior to the dismantling of the separate concrete rings. The excavator and the manipulator carrier system will be operated alternately. Main boundary condition for all the newly designed equipment is the decommissioning housing of limited space within the reactor building containment. To allow for a continuous removal of the concrete rubble, an additional opening on the lowest level of the reactor shaft will be made. All equipment and the interaction of the tools have to be tested before use in the controlled area. Therefore a full-scale model of the biological shield will be provided in a mock-up. The tests will be performed in early 2014. The dismantling of the biological shield is scheduled for 2015. (authors)

Neff, Sylvia; Graf, Anja; Petrick, Holger; Rothschmitt, Stefan [WAK Rueckbau- und Entsorgungs- GmbH, P.O.Box 12 63, 76339 Eggenstein- Leopoldshafen (Germany)] [WAK Rueckbau- und Entsorgungs- GmbH, P.O.Box 12 63, 76339 Eggenstein- Leopoldshafen (Germany); Klute, Stefan [Siempelkamp Nukleartechnik GmbH, Am Taubenfeld 25/1, 69123 Heidelberg (Germany)] [Siempelkamp Nukleartechnik GmbH, Am Taubenfeld 25/1, 69123 Heidelberg (Germany); Stanke, Dieter [Siempelkamp NIS Ingenieurgesellschaft mbH, Industriestrasse 13, 63755 Alzenau (Germany)] [Siempelkamp NIS Ingenieurgesellschaft mbH, Industriestrasse 13, 63755 Alzenau (Germany)

2013-07-01T23:59:59.000Z

495

Depolarisation cooling of an atomic cloud  

E-Print Network (OSTI)

We propose a cooling scheme based on depolarisation of a polarised cloud of trapped atoms. Similar to adiabatic demagnetisation, we suggest to use the coupling between the internal spin reservoir of the cloud and the external kinetic reservoir via dipolar relaxation to reduce the temperature of the cloud. By optical pumping one can cool the spin reservoir and force the cooling process. In case of a trapped gas of dipolar chromium atoms, we show that this cooling technique can be performed continuously and used to approach the critical phase space density for BEC

S. Hensler; A. Greiner; J. Stuhler; T. Pfau

2005-05-13T23:59:59.000Z

496

Proton Mass Shift in Muonic Hydrogen Atom  

E-Print Network (OSTI)

We show that the value of the proton mass depends on each bound state of muonic or electronic hydrogen atom. The charged particle bound to the proton produces magnetic field inside the proton. This makes a change to the amount of chiral condensate inside the proton. The change gives rise to the shift in the value of the proton mass. Numerically, the shift in the $2S$ state of the muonic hydrogen atom can be of the order of $0.1$ meV. The effect may solve the puzzle of the proton radius.

Aiichi Iwazaki

2014-08-11T23:59:59.000Z

497

Collective mechanism for atomic recombination in plasmas  

Science Journals Connector (OSTI)

A new mechanism is proposed for atomic recombination in plasmas, whereby the binding energy is carried away by a plasmon. It is suggested that this mechanism may compete with radiative and three-body modes in the case of recombination to sufficiently highly excited and perturbed states of hydrogen. A procedure for calculation of the transition rate is outlined in a model which treats the plasma oscillations by the Bohm-Pines canonical transformation and the atomic bound states by a second canonical transformation.

M. D. Girardeau and F. A. Gutierrez

1988-08-01T23:59:59.000Z

498

Nuclear structure effects in light muonic atoms  

E-Print Network (OSTI)

Nuclear structure corrections to energy levels of light muonic atoms are derived with particular attention to the correct nuclear mass dependence. The obtained result for the 2P-2S transition of 1.717(19) meV serves for determination of the nuclear charge radius from the spectroscopic measurement in muonic deuterium.

Pachucki, Krzysztof

2015-01-01T23:59:59.000Z

499

Multistage Zeeman deceleration of hydrogen atoms  

SciTech Connect

The deceleration of beams of neutral particles possessing an electron spin with time-dependent inhomogeneous magnetic fields is demonstrated experimentally. Half the kinetic energy of a velocity-selected part of a pulsed supersonic beam of hydrogen atoms in the ground state is removed using six pulsed magnetic field stages.

Vanhaecke, Nicolas [Physical Chemistry, ETH Zuerich, CH-8093 Zuerich (Switzerland); Laboratoire Aime Cotton, batiment 505, Campus d'Orsay, 91405 Orsay (France); Meier, Urban; Andrist, Markus; Meier, Beat H.; Merkt, Frederic [Physical Chemistry, ETH Zuerich, CH-8093 Zuerich (Switzerland)

2007-03-15T23:59:59.000Z

500

Nano-soldering to single atomic layer  

DOE Patents (OSTI)

A simple technique to solder submicron sized, ohmic contacts to