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Note: This page contains sample records for the topic "atomic shield 1947-1952" from the National Library of EnergyBeta (NLEBeta).
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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

Exact solutions for perturbed confined hydrogen atoms: Polarizabilities and nuclear shielding factors  

Science Conference Proceedings (OSTI)

We extend our recent treatment of a well-known model of a nonrelativistic hydrogen-like atom confined within an impenetrable spherical 'box' of radius R. Analytical closed-form solutions are presented for the first-order perturbation corrections appropriate to the dipole polarization of all s states. Exact solutions are expressed conveniently in terms of Kummer (confluent hypergeometric) M functions, exactly as for the field-free atom, by exploiting several well-known recurrence and differential relations for these functions. The M functions and all necessary integrals are evaluated using standard MAPLE routines, which exploit analytical properties of these functions. The accuracy of our procedures has been checked by a similar calculation of the dipole shielding factors. Our procedures are easily extended to states of nonzero angular momentum, as well as to higher-multipole perturbations. Our exact values may be of interest in assessing the utility of this simple model of atomic confinement.

Burrows, B.L. [Mathematics Section, Faculty of Computing, Engineering and Technology, Staffordshire University, Beaconside, Stafford, ST18 0DG (United Kingdom); Cohen, M. [Department of Physical Chemistry, Hebrew University of Jerusalem, Jerusalem, 91904 (Israel)

2005-09-15T23:59:59.000Z

3

A study of form-principles affording shielding from atomic fallout  

E-Print Network (OSTI)

The United States Department of Defense-Office of Civil Defense has for several years trained architects and engineers in the design of structures to resist atomic blast and for the protection from gamma radiation (hereinafter called "fallout"). The D.O.D.-O.C.D. program, for the moat part, has placed emphasis on methods of calculating "attenuation", which is a measurement of the reduction of radiation through masses of shielding materials, through distance and other means. The calculations determine the amount of shielding afforded by a given structure or design situation; and thus assess that structure's acceptability as a fallout shelter. Thus far, this pragmatic approach has usually resulted in rather strict, utilitarian solutions in the design of shelters, many of which would tend to produce claustrophobia and panic. For example, in the one publication of the D.O.D.-O.C.D. to date showing case studies of shelters incorporated into hypothetical buildings, two out of four examples shown are basement shelters, and none of the four permit any natural light or natural ventilation. None succeed in making the space functional and inhabitable primarily for its normal day-to-day use without having foreboding shelter connotations. None of the four case studies permit any psychological outlets, several of which are possible, such as a) Occupants may be permitted secondary contact with the outside through indirect natural light and direct sound; b) Occupants may, by stepping around a corner, be able to see directly out with minor exposure; c) Occupants may even be permitted a complete exposure to the out-of-doors for a moment without endangering the other shelter occupants. All of this is feasible and desirable. It appears that designing for fallout will be an increasing factor in all types of structures in the foreseeable future. To assist architects with such design problems, this thesis is being written to investigate certain form-principles supplementing those generally used in shelter design. It also tests the validity of these form-principles through application of the D.O.D.-O.C.D. procedures to provide architects with positive design tools in this specialized field of design. Finally, it shows the incorporation of the form-principles into a hypothetical design.

Lanford, Samuel Taylor

1963-01-01T23:59:59.000Z

4

Page not found | Department of Energy  

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

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.govmanagement...

5

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

6

Modular shield  

DOE Patents (OSTI)

A modular system for containing projectiles has a sheet of material including at least a polycarbonate layer held by a metal frame having a straight frame member corresponding to each straight edge of the sheet. Each frame member has a U-shaped shield channel covering and holding a straight edge of the sheet and an adjacent U-shaped clamp channel rigidly held against the shield channel. A flexible gasket separates each sheet edge from its respective shield channel; and each frame member is fastened to each adjacent frame member only by clamps extending between adjacent clamp channels.

Snyder, Keith W. (Sandia Park, NM)

2002-01-01T23:59:59.000Z

7

REACTOR SHIELD  

DOE Patents (OSTI)

Radiation shield construction is described for a nuclear reactor. The shield is comprised of a plurality of steel plates arranged in parallel spaced relationship within a peripheral shell. Reactor coolant inlet tubes extend at right angles through the plates and baffles are arranged between the plates at right angles thereto and extend between the tubes to create a series of zigzag channels between the plates for the circulation of coolant fluid through the shield. The shield may be divided into two main sections; an inner section adjacent the reactor container and an outer section spaced therefrom. Coolant through the first section may be circulated at a faster rate than coolant circulated through the outer section since the area closest to the reactor container is at a higher temperature and is more radioactive. The two sections may have separate cooling systems to prevent the coolant in the outer section from mixing with the more contaminated coolant in the inner section.

Wigner, E.P.; Ohlinger, L.E.; Young, G.J.; Weinberg, A.M.

1959-02-17T23:59:59.000Z

8

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.

9

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

10

Shielding Integrity Services, Inc.  

Science Conference Proceedings (OSTI)

... Shield attenuation measurement. ... [12/SE-003] IEEE Std 299 (2006) Measuring the Effectiveness of Electromagnetic Shielding Enclosures. ...

2013-09-27T23:59:59.000Z

11

SETTABLE NEUTRON RADIATION SHIELDING MATERIAL  

DOE Patents (OSTI)

A settable, viscous, putty-like shielding composition is described. It consists of an intimate admixture of a major proportion of a compound having a ratio of hydrogen atoms to all other atoms therein within the range of from 0.5: 1 to 2:l. from 0.5 to 10% by weight of boron, and a fluid resinous carrier This composition when cured is adapted to attenuate fast moving neutrons and capture slow moving neutrons.

Axelrad, I.R.

1960-11-22T23:59:59.000Z

12

atomic  

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

theory and fundamental quantum mechanics In addition to research on hadronic and nuclear physics, we also conduct research in atomic physics, neutron physics, and quantum...

13

Corium shield  

DOE Patents (OSTI)

A shield for restricting molten corium from flowing into a water sump disposed in a floor of a containment vessel includes upper and lower walls which extend vertically upwardly and downwardly from the floor for laterally bounding the sump. The upper wall includes a plurality of laterally spaced apart flow channels extending horizontally therethrough, with each channel having a bottom disposed coextensively with the floor for channeling water therefrom into the sump. Each channel has a height and a length predeterminedly selected for allowing heat from the molten corium to dissipate through the upper and lower walls as it flows therethrough for solidifying the molten corium therein to prevent accumulation thereof in the sump.

McDonald, Douglas B. (Pleasanton, CA); Buchholz, Carol E. (San Jose, CA)

1994-01-01T23:59:59.000Z

14

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

2013-10-22T23:59:59.000Z

15

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.

Ribeiro, Sofia

2013-01-01T23:59:59.000Z

16

Radiation Shielding Applications  

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

Shielding Radiation Shielding Applications Heavy concrete is standard concrete in which conventional aggregate (typically gravel) is replaced with aggregate composed of a dense...

17

rf_shield.PDF  

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

April 2001 Interaction Region RF Shield Issues G. Stupakov and T.O. Raubenheimer Stanford Linear Accelerator Center Stanford, California 102300 Interaction Region RF Shield...

18

John R. Shields  

Science Conference Proceedings (OSTI)

John R. Shields. ... Mr. Shields joined the National Bureau of Standards (NBS) in August 1986 as an Engineering Technician at the Large Fire Lab. ...

2012-07-06T23:59:59.000Z

19

NEUTRONIC REACTOR SHIELD  

DOE Patents (OSTI)

The reactor radiation shield material is comprised of alternate layers of iron-containing material and compressed cellulosic material, such as masonite. The shielding material may be prefabricated in the form of blocks, which can be stacked together in ary desired fashion to form an effective shield.

Fermi, E.; Zinn, W.H.

1957-09-24T23:59:59.000Z

20

Thermal testing of solid neutron shielding materials  

Science Conference Proceedings (OSTI)

Two legal-weight truck casks the GA-4 and GA-9, will carry four PWR and nine BWR spent fuel assemblies, respectively. Each cask has a solid neutron shielding material separating the steel body and the outer steel skin. In the thermal accident specified by NRC regulations in 10CFR Part 71, the cask is subjected to an 800[degree]C environment for 30 minutes. The neutron shield need not perform any shielding function during or after the thermal accident, but its behavior must not compromise the ability of the cask to contain the radioactive contents. In May-June 1989 the first series of full-scale thermal tests was performed on three shielding materials: Bisco Products NS-4-FR, and Reactor Experiments RX-201 and RX-207. The tests are described in Thermal Testing of Solid Neutron Shielding Materials, GA-AL 9897, R. H. Boonstra, General Atomics (1990), and demonstrated the acceptability of these materials in a thermal accident. Subsequent design changes to the cask rendered these materials unattractive in terms of weight or adequate service temperature margin. For the second test series, a material specification was developed for a polypropylene based neutron shield with a softening point of at least 280[degree]F. The neutron shield materials tested were boronated (0.8--4.5%) polymers (polypropylene, HDPE, NS-4). The Envirotech and Bisco materials are not polypropylene, but were tested as potential backup materials in the event that a satisfactory polypropylene could not be found.

Boonstra, R.H.

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Cable shield connecting device  

DOE Patents (OSTI)

A cable shield connecting device for installation on a high voltage cable of the type having a metallic shield, the device including a relatively conformable, looped metal bar for placement around a bared portion of the metallic shield to extend circumferentially around a major portion of the circumference of the metallic shield while being spaced radially therefrom, a plurality of relatively flexible metallic fingers affixed to the bar, projecting from the bar in an axial direction and spaced circumferentially along the bar, each finger being attached to the metallic shield at a portion located remote from the bar to make electrical contact with the metallic shield, and a connecting conductor integral with the bar.

Silva, Frank A. (Basking Ridge, NJ)

1979-01-01T23:59:59.000Z

22

RADIATION SHIELDING DEVICE  

DOE Patents (OSTI)

ABS>A radiation shield that is suitable for the protection of personnel from both gamma rays and nentrons is described. The shield is comprised of a hollow wall and an aggregate consisting of iron and water in approximately equal amounts by volume substantially filling the wall. A means is provided to circulate the water through the wall to cool the shield when in use.

Wigner, E.P.; Young, G.J.

1958-09-23T23:59:59.000Z

23

Shield for Water Boiler  

SciTech Connect

Siimplified shielding calculations indicating the proposed design for the water boiler assembly will reduce the radiation at normal operaton to values well below those which are considered tolerable.

Balent, R.

1951-08-08T23:59:59.000Z

24

RADIATION SHIELDING COMPOSITION  

DOE Patents (OSTI)

A light weight radiation shielding composition is described whose mechanical and radiological properties can be varied within wide limits. The composition of this shielding material consists of four basic ingredients: powder of either Pb or W, a plastic resin, a resin plasticizer, and a polymerization catalyst to promote an interaction of the plasticizer with the plastic resin. Air may be mixed into the above ingredients in order to control the density of the final composition. For equivalent gamma attenuation, the shielding composition weighs one-third to one-half as much as conventional Pb shielding. (AEC)

Dunegan, H.L.

1963-01-29T23:59:59.000Z

25

Gamma ray detector shield  

DOE Patents (OSTI)

A gamma ray detector shield comprised of a rigid, lead, cylindrical-shaped vessel having upper and lower portions with an pneumatically driven, sliding top assembly. Disposed inside the lead shield is a gamma ray scintillation crystal detector. Access to the gamma detector is through the sliding top assembly.

Ohlinger, R.D.; Humphrey, H.W.

1985-08-26T23:59:59.000Z

26

MEANS FOR SHIELDING REACTORS  

DOE Patents (OSTI)

A reactor of the heterageneous, heavy water moderated type is described. The reactor is comprised of a plurality of vertically disposed fuel element tubes extending through a tank of heavy water moderator and adapted to accommodate a flow of coolant water in contact with the fuel elements. A tank containing outgoing coolant water is disposed above the core to function is a radiation shield. Unsaturated liquid hydrocarbon is floated on top of the water in the shield tank to reduce to a minimum the possibility of the occurrence of explosive gaseous mixtures resulting from the neutron bombardment of the water in the shield tank.

Garrison, W.M.; McClinton, L.T.; Burton, M.

1959-03-10T23:59:59.000Z

27

Adhesive particle shielding  

DOE Patents (OSTI)

An efficient device for capturing fast moving particles has an adhesive particle shield that includes (i) a mounting panel and (ii) a film that is attached to the mounting panel wherein the outer surface of the film has an adhesive coating disposed thereon to capture particles contacting the outer surface. The shield can be employed to maintain a substantially particle free environment such as in photolithographic systems having critical surfaces, such as wafers, masks, and optics and in the tools used to make these components, that are sensitive to particle contamination. The shield can be portable to be positioned in hard-to-reach areas of a photolithography machine. The adhesive particle shield can incorporate cooling means to attract particles via the thermophoresis effect.

Klebanoff, Leonard Elliott (Dublin, CA); Rader, Daniel John (Albuquerque, NM); Walton, Christopher (Berkeley, CA); Folta, James (Livermore, CA)

2009-01-06T23:59:59.000Z

28

SHIELD certification package  

Science Conference Proceedings (OSTI)

Certification as applied to existing computer codes includes the verification and validation process, placing the code in configuration control, establishing user qualification standards and training requirements. All software intended for use in critical calculations must be certified. This report is intended to fulfill the requirements for the certification of the SHIELD, SHLDED, GEDIT, GENPRT, FIPROD, FPCALC, and PROCES modules of the SHIELD system built February, 1992, by W.S. Parks. These modules are used for burnup, cooling, separate, and edit calculations.

Boman, C.

1992-02-01T23:59:59.000Z

29

Hydrogen Induced Cracking of Drip Shield  

DOE Green Energy (OSTI)

One potential failure mechanism for titanium and its alloys under repository conditions is via the absorption of atomic hydrogen in the metal crystal lattice. The resulting decreased ductility and fracture toughness may lead to brittle mechanical fracture called hydrogen-induced cracking (HIC) or hydrogen embrittlement. For the current design of the engineered barrier without backfill, HIC may be a problem since the titanium drip shield can be galvanically coupled to rock bolts (or wire mesh), which may fall onto the drip shield, thereby creating conditions for hydrogen production by electrochemical reaction. The purpose of this scientific analysis and modeling activity is to evaluate whether the drip shield will fail by HIC or not under repository conditions within 10,000 years of emplacement. This Analysis and Model Report (AMR) addresses features, events, and processes related to hydrogen induced cracking of the drip shield. REV 00 of this AMR served as a feed to ''Waste Package Degradation Process Model Report'' and was developed in accordance with the activity section ''Hydrogen Induced Cracking of Drip Shield'' of the development plan entitled ''Analysis and Model Reports to Support Waste Package PMR'' (CRWMS M&O 1999a). This AMR, prepared according to ''Technical Work Plan for: Waste Package Materials Data Analyses and Modeling'' (BSC 2002), is to feed the License Application.

G. De

2003-02-24T23:59:59.000Z

30

Microscreen radiation shield for thermoelectric generator  

DOE Patents (OSTI)

The present invention provides a microscreen radiation shield which reduces radiative heat losses in thermoelectric generators such as sodium heat engines without reducing the efficiency of operation of such devices. The radiation shield is adapted to be interposed between a reaction zone and a means for condensing an alkali metal vapor in a thermoelectric generator for converting heat energy directly to electrical energy. The radiation shield acts to reflect infrared radiation emanating from the reaction zone back toward the reaction zone while permitting the passage of the alkali metal vapor to the condensing means. The radiation shield includes a woven wire mesh screen or a metal foil having a plurality of orifices formed therein. The orifices in the foil and the spacing between the wires in the mesh is such that radiant heat is reflected back toward the reaction zone in the interior of the generator, while the much smaller diameter alkali metal atoms such as sodium pass directly through the orifices or along the metal surfaces of the shield and through the orifices with little or no impedance.

Hunt, Thomas K. (Ann Arbor, MI); Novak, Robert F. (Farmington Hills, MI); McBride, James R. (Ypsilanti, MI)

1990-01-01T23:59:59.000Z

31

Radiation shielding composition  

DOE Patents (OSTI)

A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

1998-01-01T23:59:59.000Z

32

Radiation shielding composition  

DOE Patents (OSTI)

A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

2000-12-26T23:59:59.000Z

33

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

34

Glove box shield  

DOE Patents (OSTI)

According to the present invention, a shield for a glove box housing radioactive material is comprised of spaced apart clamping members which maintain three overlapping flaps in place therebetween. There is a central flap and two side flaps, the side flaps overlapping at the interior edges thereof and the central flap extending past the intersection of the side flaps in order to insure that the shield is always closed when the user withdraws his hand from the glove box. Lead loaded neoprene rubber is the preferred material for the three flaps, the extent of lead loading depending upon the radiation levels within the glove box.

Brackenbush, Larry W. (Richland, WA); Hoenes, Glenn R. (Richland, WA)

1981-01-01T23:59:59.000Z

35

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

36

The Tower Shielding Facility: Its glorious past  

Science Conference Proceedings (OSTI)

The Tower Shielding Facility (TSF) is the only reactor facility in the US that was designed and built for radiation-shielding studies in which both the reactor source and shield samples could be raised into the air to allow measurements to be made without interference from ground scattering or other spurious effects. The TSF proved its usefulness as many different programs were successfully completed. It became active in work for the Defense Atomic Support Agency (DASA) Space Nuclear Auxiliary Power, Defense Nuclear Agency, Liquid Metal Fast Breeder Reactor Program, the Gas-Cooled and High-Temperature Gas-Cooled Reactor programs, and the Japanese-American Shielding Program of Experimental Research, just to mention a few of the more extensive ones. The history of the TSF as presented in this report describes the various experiments that were performed using the different reactors. The experiments are categorized as to the programs which they supported and placed in corresponding chapters. The experiments are described in modest detail, along with their purpose when appropriate. Discussion of the results is minimal, but references are given to more extensive topical reports.

Muckenthaler, F.J.

1997-05-07T23:59:59.000Z

37

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

38

Multilayer radiation shield  

SciTech Connect

A power generation system including: a generator including a rotor including a superconductive rotor coil coupled to a rotatable shaft; a first prime mover drivingly coupled to the rotatable shaft; and a thermal radiation shield, partially surrounding the rotor coil, including at least a first sheet and a second sheet spaced apart from the first sheet by centripetal force produced by the rotatable shaft. A thermal radiation shield for a generator including a rotor including a super-conductive rotor coil including: a first sheet having at least one surface formed from a low emissivity material; and at least one additional sheet having at least one surface formed from a low emissivity material spaced apart from the first sheet by centripetal force produced by the rotatable shaft, wherein each successive sheet is an incrementally greater circumferential arc length and wherein the centripetal force shapes the sheets into a substantially catenary shape.

Urbahn, John Arthur (Saratoga Springs, NY); Laskaris, Evangelos Trifon (Niskayuna, NY)

2009-06-16T23:59:59.000Z

39

Justification for Shielded Receiver Tube Additional Lead Shielding  

Science Conference Proceedings (OSTI)

In order to reduce high radiation dose rates encountered when core sampling some radioactive waste tanks the addition of 240 lbs. of lead shielding is being considered to the shielded receiver tube on core sample trucks No.1, No.3 and No.4. The lead shielding is 4 inch diameter x 1/2 inch thick half rounds that have been installed around the SR tube over its' full length. Using three unreleased but independently reviewed structural analyses HNF-6018 justifies the addition of the lead shielding.

BOGER, R.M.

2000-04-11T23:59:59.000Z

40

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

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Noise modeling from high-permeability shields using Kirchhoff equations  

SciTech Connect

Progress in the development of high-sensitivity magnetic-field measurements has stimulated interest in understanding magnetic noise of conductive materials, especially of magnetic shields (DC or rf) based on high-permeability materials and/or high-conductivity materials. For example, SQUIDs and atomic magnetometers have been used in many experiments with mu-metal shields, and additionally SQUID systems frequently have rf shielding based on thin conductive materials. Typical existing approaches to modeling noise only work with simple shield and sensor geometries while common experimental setups today consist of multiple sensor systems arbitrary shapes and complex shield geometries. With complex sensor arrays used in, for example, MEG and Ultra Low Field MRI studies the knowledge of the noise correlation between sensors is as important as the knowledge of the noise itself. This is crucial for incorporating efficient noise cancelation schemes for the system. We developed an approach that allows us to calculate the Johnson noise for any geometrically shaped shield and multiple sensor systems. The approach uses a fraction of the processing power of other approaches and with a multiple sensor system our approach not only calculates the noise for each sensor but it also calculates the noise correlation matrix between sensors. Here we will show the algorithm and examples where it can be implemented.

Sandin, Henrik J [Los Alamos National Laboratory; Volegov, Petr L [Los Alamos National Laboratory; Espy, Michelle A [Los Alamos National Laboratory; Matlashov, Andrei N [Los Alamos National Laboratory; Savukov, Igor M [Los Alamos National Laboratory; Schultz, Larry J [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

42

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

43

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

44

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

45

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)

2007-05-22T23:59:59.000Z

46

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

47

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

48

Status of NAÏADE 1 Shielding Benchmarks  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Jean-Claude Nimal

49

A (CERN) History of Accelerator Shielding  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Marco Silari

50

Development of Novel Neutron Shielding Concrete  

Science Conference Proceedings (OSTI)

Shielding Materials / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Koichi Okuno; Masayoshi Kawai; Hitoshi Yamada

51

High-Heat-Resistant Neutron Shielding Resin  

Science Conference Proceedings (OSTI)

Shielding Materials / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Atsuhiko M. Sukegawa; Koichi Okuno; Shinji Sakurai

52

SNF shipping cask shielding analysis  

Science Conference Proceedings (OSTI)

The Waste Management and Remedial Action Division has planned a modification sequence for storage facility 7827 in the Solid Waste Storage Area (SWSA). The modification cycle is: (1) modify an empty caisson, (2) transfer the spent nuclear fuel (SNF) of an occupied caisson to a hot cell in building 3525 for inspection and possible repackaging, and (3) return the package to the modified caisson in the SWSA. Although the SNF to be moved is in the solid form, it has different levels of activity. Thus, the following 5 shipping casks will be available for the task: the Loop Transport Carrier, the In- Pile Loop LITR HB-2 Carrier, the 6.5-inch HRLEL Carrier, the HFIR Hot Scrap Carrier, and the 10-inch ORR Experiment Removal Shield Cask. This report describes the shielding tasks for the 5 casks: determination of shielding characteristics, any streaming avenues, estimation of thermal limits, and shielding calculational uncertainty for use in the transportation plan.

Johnson, J.O.; Pace, J.V. III

1996-01-01T23:59:59.000Z

53

Transient heat flux shielding using thermal metamaterials  

E-Print Network (OSTI)

We have developed a heat shield based on a metamaterial engineering approach to shield a region from transient diffusive heat flow. The shield is designed with a multilayered structure to prescribe the appropriate spatial profile for heat capacity, density, and thermal conductivity of the effective medium. The heat shield was experimentally compared to other isotropic materials.

Narayana, Supradeep; Sato, Yuki

2013-01-01T23:59:59.000Z

54

Hydrogen-Induced Cracking of the Drip Shield  

DOE Green Energy (OSTI)

Hydrogen-induced cracking is characterized by the decreased ductility and fracture toughness of a material due to the absorption of atomic hydrogen in the metal crystal lattice. Corrosion is the source of hydrogen generation. For the current design of the engineered barrier without backfill, hydrogen-induced cracking may be a concern because the titanium drip shield can be galvanically coupled to rock bolts (or wire mesh), which may fall onto the drip shield, thereby creating conditions for hydrogen production by electrochemical reaction. The purpose of this report is to analyze whether the drip shield will fail by hydrogen-induced cracking under repository conditions within 10,000 years after emplacement. Hydrogen-induced cracking is a scenario of premature failure of the drip shield. This report develops a realistic model to assess the form of hydrogen-induced cracking degradation of the drip shield under the hydrogen-induced cracking. The scope of this work covers the evaluation of hydrogen absorbed due to general corrosion and galvanic coupling to less noble metals (e.g., Stainless Steel Type 316 and carbon steels) under the repository conditions during the 10,000-year regulatory period after emplacement and whether the absorbed hydrogen content will exceed the critical hydrogen concentration value, above which the hydrogen-induced cracking is assumed to occur. This report also provides the basis for excluding the features, events, and processes (FEPs) related to hydrogen-induced cracking of the drip shield with particular emphasis on FEP 2.1.03.04.OB, hydride cracking of drip shields (DTN: M00407SEPFEPLA.000 [DIRS 170760]). This report is prepared according to ''Technical Work Plan (TWP) for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 169944]).

F. Hua

2004-09-07T23:59:59.000Z

55

Neutronic reactor thermal shield  

DOE Patents (OSTI)

1. The combination with a plurality of parallel horizontal members arranged in horizontal and vertical rows, the spacing of the members in all horizontal rows being equal throughout, the spacing of the members in all vertical rows being equal throughout; of a shield for a nuclear reactor comprising two layers of rectangular blocks through which the members pass generally perpendicularly to the layers, each block in each layer having for one of the members an opening equally spaced from vertical sides of the block and located closer to the top of the block than the bottom thereof, whereby gravity tends to make each block rotate about the associated member to a position in which the vertical sides of the block are truly vertical, the openings in all the blocks of one layer having one equal spacing from the tops of the blocks, the openings in all the blocks of the other layer having one equal spacing from the tops of the blocks, which spacing is different from the corresponding spacing in the said one layer, all the blocks of both layers having the same vertical dimension or length, the blocks of both layers consisting of relatively wide blocks and relatively narrow blocks, all the narrow blocks having the same horizontal dimension or width which is less than the horizontal dimension or width of the wide blocks, which is the same throughout, each layer consisting of vertical rows of narrow blocks and wide blocks alternating with one another, each vertical row of narrow blocks of each layer being covered by a vertical row of wide blocks of the other layer which wide blocks receive the same vertical row of members as the said each vertical row of narrow blocks, whereby the rectangular perimeters of each block of each layer is completely out of register with that of each block in the other layer.

Lowe, Paul E. (Blue Ash, OH)

1976-06-15T23:59:59.000Z

56

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. (Greenbelt, MD); Krill, Stephen J. (Arlington, VA); Murray, Alexander P. (Gaithersburg, MD)

2005-11-01T23:59:59.000Z

57

Radiation Shielding Materials and Containers Incorporating Same  

Science Conference Proceedings (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

58

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

59

Composite materials for electromagnetic shielding  

Science Conference Proceedings (OSTI)

The paper shows up the research results on processing and characterization of composite materials with polymeric matrix (silicone rubber). The materials obtained in laboratory contain metallized nettling like reinforcement material and powdery graphite ... Keywords: attenuation, filling additions, frequency, plated nettling, polymeric composite on de basis of silicone rubber, shielding effectiveness

Stoian Elena Valentina; Rizescu Cristiana; Iordache Iulian; Ionita Gheorghe; Bacinschi Zorica

2010-07-01T23:59:59.000Z

60

Residents and windows. 1. Shielding of windows  

SciTech Connect

In order to assess the influence of the shielding of windows performed by occupants in residential buildings on the heat balance of the building, the shielding of 40,000 windows was determined by observation during two heating seasons. It is shown that the demand for privacy has a large effect on the degree of window-shielding. There are also indications that many occupants trying to save energy use window-shielding as one of their means to achieve this.

Lyrberg, M.D.

1983-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

GCFR shielding design and supporting experimental programs  

SciTech Connect

The shielding for the conceptual design of the gas-cooled fast breeder reactor (GCFR) is described, and the component exposure design criteria which determine the shield design are presented. The experimental programs for validating the GCFR shielding design methods and data (which have been in existence since 1976) are also discussed.

Perkins, R.G.; Hamilton, C.J.; Bartine, D.

1980-05-01T23:59:59.000Z

62

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

63

INERT GAS SHIELD FOR WELDING  

DOE Patents (OSTI)

S>An inert gas shield is presented for arc-welding materials such as zirconium that tend to oxidize rapidly in air. The device comprises a rectangular metal box into which the welding electrode is introduced through a rubber diaphragm to provide flexibility. The front of the box is provided with a wlndow having a small hole through which flller metal is introduced. The box is supplied with an inert gas to exclude the atmosphere, and with cooling water to promote the solidification of the weld while in tbe inert atmosphere. A separate water-cooled copper backing bar is provided underneath the joint to be welded to contain the melt-through at the root of the joint, shielding the root of the joint with its own supply of inert gas and cooling the deposited weld metal. This device facilitates the welding of large workpieces of zirconium frequently encountered in reactor construction.

Jones, S.O.; Daly, F.V.

1958-10-14T23:59:59.000Z

64

STAR FORMATION IN ATOMIC GAS  

SciTech Connect

Observations of nearby galaxies have firmly established, over a broad range of galactic environments and metallicities, that star formation occurs exclusively in the molecular phase of the interstellar medium (ISM). Theoretical models show that this association results from the correlation between chemical phase, shielding, and temperature. Interstellar gas converts from atomic to molecular only in regions that are well shielded from interstellar ultraviolet (UV) photons, and since UV photons are also the dominant source of interstellar heating, only in these shielded regions does the gas become cold enough to be subject to Jeans instability. However, while the equilibrium temperature and chemical state of interstellar gas are well correlated, the timescale required to reach chemical equilibrium is much longer than that required to reach thermal equilibrium, and both timescales are metallicity-dependent. Here I show that the difference in timescales implies that, at metallicities below a few percent of the solar value, well shielded gas will reach low temperatures and proceed to star formation before the bulk of it is able to convert from atomic to molecular. As a result, at extremely low metallicities, star formation will occur in a cold atomic phase of the ISM rather than a molecular phase. I calculate the observable consequences of this result for star formation in low-metallicity galaxies, and I discuss how some current numerical models for H{sub 2}-regulated star formation may need to be modified.

Krumholz, Mark R., E-mail: krumholz@ucolick.org [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

2012-11-01T23:59:59.000Z

65

VAPOR SHIELD FOR INDUCTION FURNACE  

DOE Patents (OSTI)

This patent relates to a water-cooled vapor shield for an inductlon furnace that will condense metallic vapors arising from the crucible and thus prevent their condensation on or near the induction coils, thereby eliminating possible corrosion or shorting out of the coils. This is accomplished by placing, about the top, of the crucible a disk, apron, and cooling jacket that separates the area of the coils from the interior of the cruclbIe and provides a cooled surface upon whlch the vapors may condense.

Reese, S.L.; Samoriga, S.A.

1958-03-11T23:59:59.000Z

66

Hot Cell Window Shielding Analysis Using MCNP  

SciTech Connect

The Idaho National Laboratory Materials and Fuels Complex nuclear facilities are undergoing a documented safety analysis upgrade. In conjunction with the upgrade effort, shielding analysis of the Fuel Conditioning Facility (FCF) hot cell windows has been conducted. This paper describes the shielding analysis methodology. Each 4-ft thick window uses nine glass slabs, an oil film between the slabs, numerous steel plates, and packed lead wool. Operations in the hot cell center on used nuclear fuel (UNF) processing. Prior to the shielding analysis, shield testing with a gamma ray source was conducted, and the windows were found to be very effective gamma shields. Despite these results, because the glass contained significant amounts of lead and little neutron absorbing material, some doubt lingered regarding the effectiveness of the windows in neutron shielding situations, such as during an accidental criticality. MCNP was selected as an analysis tool because it could model complicated geometry, and it could track gamma and neutron radiation. A bounding criticality source was developed based on the composition of the UNF. Additionally, a bounding gamma source was developed based on the fission product content of the UNF. Modeling the windows required field inspections and detailed examination of drawings and material specifications. Consistent with the shield testing results, MCNP results demonstrated that the shielding was very effective with respect to gamma radiation, and in addition, the analysis demonstrated that the shielding was also very effective during an accidental criticality.

Chad L. Pope; Wade W. Scates; J. Todd Taylor

2009-05-01T23:59:59.000Z

67

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

E-Print Network (OSTI)

cylinder with heater tapes 600 CFRP (carbon fiber reinforced polymer) Castellated thermal barrier Schematic This would provide data temperature variation resistance TEMP1 path. DG_SENSE would loaded high) Conductors outside shield (6) Temperature monitoring The Module Array Shield The main purpose shield provide

California at Santa Cruz, University of

68

Thermal neutron shield and method of manufacture  

DOE Patents (OSTI)

A thermal neutron shield comprising concrete with a high percentage of the element Boron. The concrete is least 54% Boron by weight which maximizes the effectiveness of the shielding against thermal neutrons. The accompanying method discloses the manufacture of Boron loaded concrete which includes enriching the concrete mixture with varying grit sizes of Boron Carbide.

Brindza, Paul Daniel; Metzger, Bert Clayton

2013-05-28T23:59:59.000Z

69

Shielding calculations at dismantled synchrocyclotron  

SciTech Connect

The Space Radiation Effects Laboratory located in Newport News, Virginia, was operated by the College of William and Mary for the National Aeronautics and Space Administration. A synchrocyclotron which was formerly in operation in this building was removed in 1980. At several locations, the scattered radiation caused an induced radioactivity within the walls of the cyclotron room. A radiological survey has been performed to determine the amount of residual radioactivity on the walls. Calculations were performed to determine the thickness of the concrete walls and floor for shielding the residual radiation in the cyclotron room. Recommendations are made to minimize exposures from the residual radioactivity on the walls and floor of the cyclotron room to potential occupants working in the building. 19 refs., 1 fig., 2 tabs.

Yalcintas, M.G.

1987-01-01T23:59:59.000Z

70

Shield Design of the Materials Test Station's Camera Room  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

G. Muhrer; M. Wilson; Ch. Kelsey; E. Pitcher; F. Gallmeier; M. Wohlmuther

71

Radiation Shielding of a Beta-Beam Rapid Cycling Synchrotron  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Stefania Trovati; Matteo Magistris; Marco Silari

72

Transmission of Shielding Materials for Particle Therapy Facilities  

Science Conference Proceedings (OSTI)

Shielding Materials / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Nisy E. Ipe

73

Evolution of Shielding Computations for the ITER Upper ECH Launcher  

Science Conference Proceedings (OSTI)

Technical Paper / Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Photon and Neutron Transport and Shielding (DETERMINISTIC or Mc)

A. Serikov; U. Fischer; D. Grosse; P. Spaeh; D. Strauss

74

Hot cell shield plug extraction apparatus  

DOE Patents (OSTI)

An apparatus is provided for moving shielding plugs into and out of holes in concrete shielding walls in hot cells for handling radioactive materials without the use of external moving equipment. The apparatus provides a means whereby a shield plug is extracted from its hole and then swung approximately 90 degrees out of the way so that the hole may be accessed. The apparatus uses hinges to slide the plug in and out and to rotate it out of the way, the hinge apparatus also supporting the weight of the plug in all positions, with the load of the plug being transferred to a vertical wall by means of a bolting arrangement.

Knapp, Philip A. (Moore, ID); Manhart, Larry K. (Pingree, ID)

1995-01-01T23:59:59.000Z

75

Atomic History  

Science Conference Proceedings (OSTI)

... These Data Centers, one on Atomic Energy Levels and one on Atomic Transition ... After a few years Kessler went on to higher management at NIST. ...

2010-10-05T23:59:59.000Z

76

Deep Space Mission Radiation Shielding Optimization  

Science Conference Proceedings (OSTI)

Providing protection against the hazards of space radiation is a major challenge to the exploration and development of space. The great cost of added radiation shielding is a potential limiting factor in deep space missions. In the present report, we ...

Tripathi R. K.; Wilson J. W.; Cucinotta F. A.; Nealy J. E.; Clowdsley M. S.; Kim M-H. Y.

2001-07-01T23:59:59.000Z

77

Minimizing Errors Associated with Multiplate Radiation Shields  

Science Conference Proceedings (OSTI)

Multiplate radiation shield errors are examined using the following techniques: 1) ray tracing analysis, 2) wind tunnel experiments, 3) numerical flow simulations, and 4) field testing. The authors’ objectives are to develop guidelines for ...

Scott J. Richardson; Fred V. Brock; Steven R. Semmer; Cathy Jirak

1999-11-01T23:59:59.000Z

78

Reliability Methods for Shield Design Process  

Science Conference Proceedings (OSTI)

Providing protection against the hazards of space radiation is a major challenge to the exploration and development of space. The great cost of added radiation shielding is a potential limiting factor in deep space operations. In this enabling technology

R. K. Tripathi; J. W. Wilson

2003-01-01T23:59:59.000Z

79

Instability of Shielded Surface Temperature Vortices  

Science Conference Proceedings (OSTI)

The stability characteristics of the surface quasigeostrophic shielded Rankine vortex are found using a linearized contour dynamics model. Both the normal modes and nonmodal evolution of the system are analyzed and the results are compared with ...

Benjamin J. Harvey; Maarten H. P. Ambaum; Xavier J. Carton

2011-05-01T23:59:59.000Z

80

Formal derivation of optimal active shielding for low-power on-chip buses  

Science Conference Proceedings (OSTI)

Passive shielding has been used to reduce capacitive coupling effects of adjacent bus lines by inserting passive ground or power lines (shields) between the bus lines. Active shielding is another shielding technique, in which the shield is allowed to ...

M. Ghonemia; Y. Ismail

2004-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Nuclear reactor shield including magnesium oxide  

DOE Patents (OSTI)

An improvement in nuclear reactor shielding of a type used in reactor applications involving significant amounts of fast neutron flux, the reactor shielding including means providing structural support, neutron moderator material, neutron absorber material and other components as described below, wherein at least a portion of the neutron moderator material is magnesium in the form of magnesium oxide either alone or in combination with other moderator materials such as graphite and iron.

Rouse, Carl A. (Del Mar, CA); Simnad, Massoud T. (La Jolla, CA)

1981-01-01T23:59:59.000Z

82

Phase Conductor and Shield Wire Corrosion  

Science Conference Proceedings (OSTI)

As new inspection technologies for conductors and shield wires develop and mature, the assessment process becomes more accurate in identifying and quantifying flaws. With better accuracy, condition assessment can be less conservative, thus allowing utilities to save money by keeping conductors in service for longer periods. This report, which includes the results of a survey of EPRI member utilities on phase conductor and shield wire installations, inspections, and failures, updates recent EPRI work on c...

2007-12-20T23:59:59.000Z

83

X-ray transmissive debris shield  

DOE Patents (OSTI)

A composite window structure is described for transmitting x-ray radiation and for shielding radiation generated debris. In particular, separate layers of different x-ray transmissive materials are laminated together to form a high strength, x-ray transmissive debris shield which is particularly suited for use in high energy fluences. In one embodiment, the composite window comprises alternating layers of beryllium and a thermoset polymer.

Spielman, Rick B. (Albuquerque, NM)

1994-01-01T23:59:59.000Z

84

NEUTRON REACTOR HAVING A Xe$sup 135$ SHIELD  

DOE Patents (OSTI)

Shielding for reactors of the type in which the fuel is a chain reacting liquid composition comprised essentially of a slurry of fissionable and fertile material suspended in a liquid moderator is discussed. The neutron reflector comprises a tank containing heavy water surrounding the reactor, a shield tank surrounding the reflector, a gamma ray shield surrounding said shield tank, and a means for conveying gaseous fission products, particularly Xe/sup 135/, from the reactor chamber to the shield tank, thereby serving as a neutron shield by capturing the thermalized neutrons that leak outwardly from the shield tank.

Stanton, H.E.

1957-10-29T23:59:59.000Z

85

Health physics support for thermal shield repair at Connecticut Yankee  

Science Conference Proceedings (OSTI)

This article describes the radiation and safety controls used by Connecticut Yankee Atomic Power Company to support underwater repair work on the Haddam Neck Plant's core barrel thermal shield. The work was conducted by divers in the reactor cavity using remote tools and protected by a specially-constructed physical barrier that restricted their movements to a carefully defined and thoroughly surveyed area. A unique dosimetry test rig was used to determine the dose rate profiles within the work areas, and all underwater survey equipment was qualified against personnel dosimetric devices. Underwater operations were monitored and controlled by remote means (video surveillance and dosimetry telemetry), and health physics technicians were rotated through job coverage to avoid complacency and maximize training opportunities. A single, hot particle event occurred during one dive, but this was identified almost immediately and controlled to prevent excessive exposure to the diver.

Nevelos, W.F.; Gates, W.J. (Connecticut Yankee Atomic Power Co., East Hampton, CT (United States))

1988-10-01T23:59:59.000Z

86

Cosmic Ray Interactions in Shielding Materials  

SciTech Connect

This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earth’s surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that will stop the induced neutrons. The interaction of the different cosmic-ray components at ground level (protons, neutrons, muons) with their wide energy range (from kilo-electron volts to giga-electron volts) is a complex calculation. Monte Carlo calculations have proven to be a suitable tool for the simulation of nucleon transport, including hadron interactions and radioactive isotope production. The industry standard Monte Carlo simulation tool, Geant4, was used for this study. The result of this study is the assertion that activation at Earth’s surface is a result of the neutronic and protonic components of the cosmic-ray shower. The best material to shield against these cosmic-ray components is iron, which has the best combination of primary shielding and minimal secondary neutron production.

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J.; Troy, Meredith D.

2011-09-08T23:59:59.000Z

87

Numerical estimation on free electrons generated by shielded radioactive materials under various gaseous environments  

SciTech Connect

We report simulation results on generation of free electrons due to the presence of radioactive materials under controlled pressure and gases using a general Monte Carlo transport code (MCNPX). A radioactive material decays to lower atomic number, simultaneously producing high energy gamma rays that can generate free electrons via various scattering mechanisms. This paper shows detailed simulation works for answering how many free electrons can be generated under the existence of shielded radioactive materials as a function of pressure and types of gases.

Kim, D. S. [Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); Lee, W. S.; So, J. H. [Agency for Defence Development (ADD), Daejeon 305-152 (Korea, Republic of); Choi, E. M. [Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of); School of Electrical and Computer Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 689-798 (Korea, Republic of)

2013-06-15T23:59:59.000Z

88

Overview of SNS accelerator shielding analyses  

Science Conference Proceedings (OSTI)

The Spallation Neutron Source is an accelerator driven neutron scattering facility for materials research. During all phases of SNS development, including design, construction, commissioning and operation, extensive neutronics work was performed in order to provide adequate shielding, to assure safe facility operation from radiation protection point of view, and to optimize performance of the accelerator and target facility. Presently, most of the shielding work is concentrated on the beam lines and instrument enclosures to prepare for commissioning, safe operation and adequate radiation background in the future. Although the accelerator is built and in operation mode, there is extensive demand for shielding and activation analyses. It includes redesigning some parts of the facility, facility upgrades, designing additional structures, storage and transport containers for accelerator structures taken out of service, and performing radiation protection analyses and studies on residual dose rates inside the accelerator. (authors)

Popova, I.; Gallmeier, F. X.; Ferguson, P.; Iverson, E.; Lu, W. [ORNL/SNS, MS6475, PO Box 2008, Oak Ridge, TN 37831-6471 (United States)

2012-07-01T23:59:59.000Z

89

5/6/03-5/12/03 Monochromator goniometer and shielding ...  

Science Conference Proceedings (OSTI)

... North short walls and column shields in are place. Top shield is positioned and leveled. The laminated shielding is installed above the shutter ...

90

Hot cell shield plug extraction apparatus  

DOE Patents (OSTI)

A hot cell installation for the handling of highly radioactive material may comprise a dozen or more interconnected high density concrete vaults, the concrete vault walls having a thickness of approximately three feet. Typically, hot cells are constructed in rows so as to share as many shielding walls as possible. A typical overall length of a row of cells might be 70 yards. A secondary mechanism exists for placing certain objects into a cell. A typical hot cell has been constructed with 8 inch diameter holes through the exterior shielded walls in the vicinity of, and usually above, the viewing windows. It became evident that if the hot cell plugs could be removed and replaced conveniently significant savings in time and personnel exposure could be realized by using these 8 inch holes as entry ports. Fifteen inch cylindrical steel plugs with a diameter of eight inches weigh about two hundred pounds. The shield plug swing mechanism comprises a steel shielding plug mounted on a retraction device that enables the plug to be pulled out of the wall and supports the weight of the pulled out plug. The retraction device is mounted on a hinge, which allows the plug to be swung out of the way so that an operator can insert material into or remove it from the interior of the hot cell and then replace the plug quickly. The hinge mounting transmits the load of the retracted plug to the concrete wall.

Knapp, P.A.; Manhart, L.K.

1994-12-31T23:59:59.000Z

91

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

92

Interactions of Baroclinic Isolated Vortices: The Dominant Effect of Shielding  

Science Conference Proceedings (OSTI)

The interactions of two quasigeostrophic isolated shielded vortices are considered in a two-layer model and in the reduced-gravity approximation. Each shielded vortex is defined by a realistic horizontal profile of relative vorticity in the upper ...

S. Valcke; J. Verron

1997-04-01T23:59:59.000Z

93

Preliminary Nuclear Calculations for the Shield Test Facility  

SciTech Connect

To find the critical size of the proposed shield test facility based upon available data and present construction concepts.

Baucom, H.H.

1960-01-11T23:59:59.000Z

94

Gravity Scaling of a Power Reactor Water Shield  

Science Conference Proceedings (OSTI)

Water based reactor shielding is being considered as an affordable option for potential use on initial lunar surface reactor power systems. Heat dissipation in the shield from nuclear sources must be rejected by an auxillary thermal hydraulic cooling system. The mechanism for transferring heat through the shield is natural convection between the core surface and an array of thermosyphon radiator elements. Natural convection in a 100 kWt lunar surface reactor shield design has been previously evaluated at lower power levels (Pearson

Robert S. Reid; J. Boise Pearson

2008-01-01T23:59:59.000Z

95

Measurements of Materials Shielding Properties with 1 GeV/nuc56Fe  

DOE Green Energy (OSTI)

The design of future spacecraft such as the Crew ExplorationVehicle must take into account the radiation shielding properties of boththe structural components as well as dedicated shielding materials. Sincemodest depths of shielding stop the vast majority of Solar EnergeticParticles (SEP), the greater challenge is posed by the need to shieldcrew from the Galactic Cosmic Rays (GCR), which include highly-chargedand highly-energetic particles. Here, we report on results from testsperformed with beams of 1 GeV/nuc 56Fe at the Brookhaven NationalLaboratory. A wide variety of targets, both elemental and composite, wereplaced in the particle beams, and the spectra of particles emerging fromthe targets were measured using a stack of silicon detectors. Results arepresented primarily in terms of dose reduction per g cm-2 of targetmaterial, and support the conclusions of an earlier calculation by Wilsonet al. showing that performance improves as the shield's mass numberdecreases, with hydrogen being by far the most effective. The data alsoshow that, as depth increases, the incremental benefit of addingshielding decreases, particularlyfor aluminum and other elements withhigher atomic mass numbers.

Zeitlin, Cary; Guetersloh, Stephen B.; Heilbronn, Lawrence H.; Miller, Jack

2006-05-15T23:59:59.000Z

96

Packed rod neutron shield for fast nuclear reactors  

DOE Patents (OSTI)

A fast neutron nuclear reactor including a core and a plurality of vertically oriented neutron shield assemblies surrounding the core. Each assembly includes closely packed cylindrical rods within a polygonal metallic duct. The shield assemblies are less susceptible to thermal stresses and are less massive than solid shield assemblies, and are cooled by liquid coolant flow through interstices among the rods and duct.

Eck, John E. (Hempfield Township, Westmoreland County, PA); Kasberg, Alvin H. (Murrysville, PA)

1978-01-01T23:59:59.000Z

97

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

E-Print Network (OSTI)

: Aluminum 150 µm thick cylinder with heater tapes and 600 µm CFRP (carbon fiber reinforced polymer, Schematic 4. This tap would provide data on the temperature variation of the resistance of the TEMP1 path inside the shield (5) Conductors outside the shield (6) Temperature monitoring The Module Array Shield

California at Santa Cruz, University of

98

ANS shielding standards for light-water reactors  

SciTech Connect

The purpose of the American Nuclear Society Standards Subcommittee, ANS-6, Radiation Protection and Shielding, is to develop standards for radiation protection and shield design, to provide shielding information to other standards-writing groups, and to develop standard reference shielding data and test problems. A total of seven published ANS-6 standards are now current. Additional projects of the subcommittee, now composed of nine working groups, include: standard reference data for multigroup cross sections, gamma-ray absorption coefficients and buildup factors, additional benchwork problems for shielding problems and energy spectrum unfolding, power plant zoning design for normal and accident conditions, process radiation monitors, and design for postaccident radiological conditions.

Trubey, D.K.

1982-01-01T23:59:59.000Z

99

Electronically shielded solid state charged particle detector  

DOE Patents (OSTI)

An electronically shielded solid state charged particle detector system having enhanced radio frequency interference immunity includes a detector housing with a detector entrance opening for receiving the charged particles. A charged particle detector having an active surface is disposed within the housing. The active surface faces toward the detector entrance opening for providing electrical signals representative of the received charged particles when the received charged particles are applied to the active surface. A conductive layer is disposed upon the active surface. In a preferred embodiment, a nonconductive layer is disposed between the conductive layer and the active surface. The conductive layer is electrically coupled to the detector housing to provide a substantially continuous conductive electrical shield surrounding the active surface. The inner surface of the detector housing is supplemented with a radio frequency absorbing material such as ferrite.

Balmer, D.K.; Haverty, T.W.; Nordin, C.W.; Tyree, W.H.

1995-12-31T23:59:59.000Z

100

Supplemental heating of deposition tooling shields  

DOE Patents (OSTI)

A method of reducing particle generation from the thin coating deposited on the internal surfaces of a deposition chamber which undergoes temperature variation greater than 100.degree. C. comprising maintaining the temperature variation of the internal surfaces low enough during the process cycle to keep thermal expansion stresses between the coating and the surfaces under 500 MPa. For titanium nitride deposited on stainless steel, this means keeping temperature variations under approximately 70.degree. C. in a chamber that may be heated to over 350.degree. C. during a typical processing operation. Preferably, a supplemental heater is mounted behind the upper shield and controlled by a temperature sensitive element which provides feedback control based on the temperature of the upper shield.

Ohlhausen, James A. (Albuquerque, NM); Peebles, Diane E. (Albuquerque, NM); Hunter, John A. (Albuquerque, NM); Eckelmeyer, Kenneth H. (Albuquerque, NM)

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Enrichment Determination of Uranium in Shielded Configurations  

Science Conference Proceedings (OSTI)

The determination of the enrichment of uranium is required in many safeguards and security applications. Typical methods of determining the enrichment rely on detecting the 186 keV gamma ray emitted by {sup 235}U. In some applications, the uranium is surrounded by external shields, and removal of the shields is undesirable. In these situations, methods relying on the detection of the 186 keV gamma fail because the gamma ray is shielded easily. Oak Ridge National Laboratory (ORNL) has previously measured the enrichment of shielded uranium metal using active neutron interrogation. The method consists of measuring the time distribution of fast neutrons from induced fissions with large plastic scintillator detectors. To determine the enrichment, the measurements are compared to a calibration surface that is created from Monte Carlo simulations where the enrichment in the models is varied. In previous measurements, the geometry was always known. ORNL is extending this method to situations where the geometry and materials present are not known in advance. In the new method, the interrogating neutrons are both time and directionally tagged, and an array of small plastic scintillators measures the uncollided interrogating neutrons. Therefore, the attenuation through the item along many different paths is known. By applying image reconstruction techniques, an image of the item is created which shows the position-dependent attenuation. The image permits estimating the geometry and materials present, and these estimates are used as input for the Monte Carlo simulations. As before, simulations predict the time distribution of induced fission neutrons for different enrichments. Matching the measured time distribution to the closest prediction from the simulations provides an estimate of the enrichment. This presentation discusses the method and provides results from recent simulations that show the importance of knowing the geometry and materials from the imaging system.

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

2011-01-01T23:59:59.000Z

102

Radiation shielding for underground low-background experiments  

E-Print Network (OSTI)

The design task of creating an efficient radiation shield for the new COBRA double-beta decay experiment led to a comprehensive study of commercially available shielding materials. The aim was to find the most efficient combination of materials under the constraints of an extreme low-background experiment operating in a typical underground laboratory. All existing shield configurations for this type of experiment have been found to perform sub-optimally in comparison to the class of multilayered configurations proposed in this study. The method used here to create a specific shield configuration should yield a close to optimal result when applied to any experiment utilising a radiation shield. In particular, the survey of single material response to a given radiation source turns out to give a guideline for the construction of efficient multilayer shields.

D. Y Stewart; P. F. Harrison; B. Morgan; Y. A. Ramachers

2006-07-31T23:59:59.000Z

103

PRIMARY SHIELDING CALCULATIONS ON THE IBM 650 (ROC CODES)  

SciTech Connect

Four programs written for the IBM 650 to calculate the gamma dose rates in the primary shielding of thermal reactors are described. Their functions are outlined as follows: Program 651-calculates the core attenuation coefficient and equivalent core gamma volumetric source values for a specific core. Program 652- calculates the activation gamma source data in the shield and prepares tabular data in machine storage for Programs 653 and 654. Program 653- calculates the gamma dose rates in the shield due to gammas arising from activation of shield materials. Program 654calculates the gamma dose rates in the shield due to gammas arising in the core. Gamma photo source values are obtained on the basis of two group neutron flux distributions throughout the reactor core and shield. (W.D.M.)

Rosen, S.S.; Oby, P.V.; Caton, R.L.

1958-10-15T23:59:59.000Z

104

Shielding Design of the Spallation Neutron Source (SNS)  

Science Conference Proceedings (OSTI)

The shielding design is important for the construction of an intense high-energy accelerator facility like the proposed Spallation Neutron Source (SNS) due to its impact on conventional facility design, maintenance operations, and since the cost for the radiation shielding shares a considerable part of the total facility costs. A calculational strategy utilizing coupled high energy Monte Carlo calculations and multi-dimensional discrete ordinates calculations, along with semi-empirical calculations, was implemented to perform the conceptual design shielding assessment of the proposed SNS. Biological shields have been designed and assessed for the proton beam transport system and associated beam dumps, the target station, and the target service cell and general remote maintenance cell. Shielding requirements have been assessed with respect to weight, space, and dose-rate constraints for operating, shutdown, and accident conditions. A discussion of the proposed facility design, conceptual design shielding requirements, calculational strategy, source terms, preliminary results and conclusions, and recommendations for additional analyses are presented.

Johnson, J.O.

1998-09-17T23:59:59.000Z

105

The Spallation Neutron Source (SNS) conceptual design shielding analysis  

SciTech Connect

The shielding design is important for the construction of an intense high-energy accelerator facility like the proposed Spallation Neutron Source (SNS) due to its impact on conventional facility design, maintenance operations, and since the cost for the radiation shielding shares a considerable part of the total facility costs. A calculational strategy utilizing coupled high energy Monte Carlo calculations and multi-dimensional discrete ordinates calculations, along with semi-empirical calculations, was implemented to perform the conceptual design shielding assessment of the proposed SNS. Biological shields have been designed and assessed for the proton beam transport system and associated beam dumps, the target station, and the target service cell and general remote maintenance cell. Shielding requirements have been assessed with respect to weight, space, and dose-rate constraints for operating, shutdown, and accident conditions. A discussion of the proposed facility design, conceptual design shielding requirements calculational strategy, source terms, preliminary results and conclusions, and recommendations for additional analyses are presented.

Johnson, J.O.; Odano, N.; Lillie, R.A.

1998-03-01T23:59:59.000Z

106

Self-sealing solar collector shield  

SciTech Connect

Window structure for a solar collector shield or the like having a frame defining a row of separate window openings. A selfcontained window unit is installed in each opening. Each window unit comprises a pair of rectangular glass panes held in laterally spaced parallel relation by a peripheral window frame. A mounting frame is provided for mounting each window unit in its window opening. Each mounting frame has overlapping frame members. Adjacent side frame members of adjacent window units also overlap. The overlap is for the purpose of excluding moisture and preventing heat loss. A peripheral window seal is provided for the same purpose.

Katona, J.W.

1980-03-25T23:59:59.000Z

107

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

108

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

109

Technology Development to Improve Radiation Shielding for Material Inspections  

Science Conference Proceedings (OSTI)

Improvements in shielding are necessary to reduce radiation exposure to workers in the nuclear power industry, especially as new inspection and maintenance work tests the industry's ability to further reduce individual and collective radiation doses. To date, new shielding technologies for the nuclear industry have been limited. However, interest in developing new shielding devices has been increasing in other industry sectors such as space exploration and medicine. This report presents a thorough review...

2008-09-22T23:59:59.000Z

110

Optimization of a Mu2e production solenoid heat and radiation shield using MARS15  

SciTech Connect

A Monte-Carlo study of several Mu2e Production Solenoid (PS) absorber (heat shield) versions using the MARS15 code has been performed. Optimizations for material as well as cost (amount of tungsten) have been carried out. Studied are such quantities as the number of displacements per atom (DPA) in the helium-cooled solenoid superconducting coils, power density and dynamic heat load in various parts of the PS and its surrounding structures. Prompt dose, residual dose, secondary particle flux are also simulated in the PS structures and the experimental hall. A preliminary choice of the PS absorber design is made on the ground of these studies.

Pronskikh, V.S.; Mokhov, N.V.; /Fermilab

2011-02-01T23:59:59.000Z

111

Neutronics at Wisconsin, ORNL advances ITER shielding and internationa...  

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

Neutronics at Wisconsin, ORNL advances ITER shielding and international collaboration American Fusion News Category: U.S. ITER Link: Neutronics at Wisconsin, ORNL advances ITER...

112

Treatment of Shielding in Real-Time Source Tracking Software  

Science Conference Proceedings (OSTI)

Technical Paper / Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Radiation Measurements and General Instrumentation

Raymond T. Klann; Sergio C. de la Barrera; Richard B. Vilim

113

GMAW Shielding Gas Flow Optimisation by Refinement of Nozzle ...  

Science Conference Proceedings (OSTI)

However, sufficient shielding gas coverage of the weld region is essential for the generation of high quality welds, and drafts can be detrimental to its efficiency.

114

Space Reactor Radiation Shield Design Summary, for Information  

SciTech Connect

The purpose of this letter is to provide a summary of the Prometheus space reactor radiation shield design status at the time of program restructuring.

EC Pheil

2006-02-17T23:59:59.000Z

115

Recovery Act Workers Clear Reactor Shields from Brookhaven Lab...  

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

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...

116

APS Radiation Safety Shielding Committee for Design Reviews  

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

Minutes 2008 (restricted) 2007 (restricted) 2006 (restricted) 2005 (restricted) APS Radiation Safety Shielding Committee for Design Reviews (RSSCDR) (February 9, 2012) 1. Purpose...

117

Gravity Scaling of a Power Reactor Water Shield  

SciTech Connect

Water based reactor shielding is being considered as an affordable option for potential use on initial lunar surface reactor power systems. Heat dissipation in the shield from nuclear sources must be rejected by an auxillary thermal hydraulic cooling system. The mechanism for transferring heat through the shield is natural convection between the core surface and an array of thermosyphon radiator elements. Natural convection in a 100 kWt lunar surface reactor shield design has been previously evaluated at lower power levels (Pearson, 2006). The current baseline assumes that 5.5 kW are dissipated in the water shield, the preponderance on the core surface, but with some volumetric heating in the naturally circulating water as well. This power is rejected by a radiator located above the shield with a surface temperature of 370 K. A similarity analysis on a water-based reactor shield is presented examining the effect of gravity on free convection between a radiation shield inner vessel and a radiation shield outer vessel boundaries. Two approaches established similarity: 1) direct scaling of Rayleigh number equates gravity-surface heat flux products, 2) temperature difference between the wall and thermal boundary layer held constant on Earth and the Moon. Nussult number for natural convection (laminar and turbulent) is assumed of form Nu = CRa{sup n}. These combined results estimate similarity conditions under Earth and Lunar gravities. The influence of reduced gravity on the performance of thermosyphon heat pipes is also examined.

Reid, Robert S.; Pearson, J. Boise [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2008-01-21T23:59:59.000Z

118

SHIELDING REQUIREMENTS FOR NSLS-II.  

Science Conference Proceedings (OSTI)

Brookhaven National Laboratory is in the process of designing a new Electron Synchrotron for scientific research using synchrotron radiation. This facility, called the 'National Synchrotron Light Source II' (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors, and robotics, and a suite of scientific instruments designed to maximize the scientific output of the facility. The project scope includes the design, construction, installation, and commissioning of the following accelerators: a 200 MeV linac, a booster accelerator operating from 200 MeV to 3.0 GeV, and the storage ring which stores a maximum of 500 mA current of electrons at an energy of 3.0 GeV. It is planned to operate the facility primarily in a top-off mode, thereby maintaining the maximum variation in stored beam current to < 1%. Because of the very demanding requirements for beam emittance and synchrotron radiation brilliance, the beam life-time is expected to be low, on the order of 2-3 hours. Analysis of the bulk shielding for operating this facility and the input parameters used for this analysis are discussed in this paper. The characteristics of each of the accelerators and their operating modes are summarized with the input assumptions for the bulk shielding analysis.

JOB,P.K.; CASEY, W.R.

2008-01-02T23:59:59.000Z

119

The Making of Captain America's Shield  

Science Conference Proceedings (OSTI)

the comic book series, we know some details about the ... (EBSD), and x-ray or atom-probe tomography methods have enabled three- dimensional ... (ICME) has enabled more detailed understanding of the complex effects of processing on ...

120

Magnetic shielding system for the tokamak experimental power reactor  

SciTech Connect

A poloidal field system is proposed for superconducting tokamaks which magnetically shields the toroidal field coil windings from pulsed fields and reduces the plasma inductive requirements. The principal elements of the system are a primary air core winding and a shield-vertical-field winding. The properties of the system are investigated using computer codes for MHD equilibrium, inductances, and fields. (auth)

Marcus, F.B.; Peng, Y.K.M.; Dory, R.A.; Moore, J.R.

1975-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

General Corrosion and Localized Corrosion of the Drip Shield  

DOE Green Energy (OSTI)

The repository design includes a drip shield (BSC 2004 [DIRS 168489]) that provides protection for the waste package both as a barrier to seepage water contact and a physical barrier to potential rockfall. The purpose of the process-level models developed in this report is to model dry oxidation, general corrosion, and localized corrosion of the drip shield plate material, which is made of Ti Grade 7. This document is prepared according to ''Technical Work Plan For: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]). The models developed in this report are used by the waste package degradation analyses for TSPA-LA and serve as a basis to determine the performance of the drip shield. The drip shield may suffer from other forms of failure such as the hydrogen induced cracking (HIC) or stress corrosion cracking (SCC), or both. Stress corrosion cracking of the drip shield material is discussed in ''Stress Corrosion Cracking of the Drip Shield, the Waste Package Outer Barrier, and the Stainless Steel Structural Material'' (BSC 2004 [DIRS 169985]). Hydrogen induced cracking of the drip shield material is discussed in ''Hydrogen Induced Cracking of Drip Shield'' (BSC 2004 [DIRS 169847]).

F. Hua

2004-09-16T23:59:59.000Z

122

Field Measurement Studies on Shunt Coefficient of Lightning Shield Line  

Science Conference Proceedings (OSTI)

The shunt coefficient of lightning shield line is an important parameter, which needs to be considered when we are designing or reforming the substation grounding network, however, it is difficult to be calculated. This paper is to introduce a method ... Keywords: Short circuit current, Lightning shield line, Shunt coefficient, Shunt impedance

Dechao Li; Jinglu Li; Yuhuan Zhang

2008-10-01T23:59:59.000Z

123

Plasma shield for in-air beam processes  

SciTech Connect

A novel concept/apparatus, the Plasma Shield, is introduced in this paper. The purpose of the Plasma Shield is designed to shield a target object chemically and thermally by engulfing an area subjected to beam treatment with inert plasma. The shield consists of a vortex-stabilized arc that is employed to shield beams and workpiece area of interaction from an atmospheric or liquid environment. A vortex-stabilized arc is established between a beam generating device (laser, ion or electron gun) and a target object. The arc, which is composed of a pure noble gas, engulfs the interaction region and shields it from any surrounding liquids like water or reactive gases. The vortex is composed of a sacrificial gas or liquid that swirls around and stabilizes the arc. The successful Plasma Shield was experimentally established and very high-quality electron beam welding with partial plasma shielding was performed. The principle of the operation and experimental results are discussed in the paper.

Hershcovitch, Ady [Collider-Accelerator Department, Building 901A, Brookhaven National Laboratory, Upton, New York 11973 (United States)

2008-05-15T23:59:59.000Z

124

Shielding Integral Benchmark Archive and Database (SINBAD)  

Science Conference Proceedings (OSTI)

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

125

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

126

Fan-fold shielded electrical leads  

DOE Patents (OSTI)

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.

Rohatgi, Rajeev R. (Mountain View, CA); Cowan, Thomas E. (Livermore, CA)

1996-01-01T23:59:59.000Z

127

Superconducting magnetic shielding apparatus and method  

DOE Patents (OSTI)

Disclosed is a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped.

Clem, J.R.

1982-07-09T23:59:59.000Z

128

Superconducting magnetic shielding apparatus and method  

DOE Patents (OSTI)

Disclosed are a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped. 5 figs.

Clem, J.R.; Clem, J.R.

1983-10-11T23:59:59.000Z

129

Superconducting magnetic shielding apparatus and method  

DOE Patents (OSTI)

Disclosed is a method and apparatus for providing magnetic shielding around a working volume. The apparatus includes a hollow elongated superconducting shell or cylinder having an elongated low magnetic pinning central portion, and two high magnetic pinning end regions. Transition portions of varying magnetic pinning properties are interposed between the central and end portions. The apparatus further includes a solenoid substantially coextensive with and overlying the superconducting cylinder, so as to be magnetically coupled therewith. The method includes the steps passing a longitudinally directed current through the superconducting cylinder so as to depin magnetic reservoirs trapped in the cylinder. Next, a circumferentially directed current is passed through the cylinder, while a longitudinally directed current is maintained. Depinned magnetic reservoirs are moved to the end portions of the cylinder, where they are trapped.

Clem, John R. (Ames, IA); Clem, John R. (Ames, IA)

1983-01-01T23:59:59.000Z

130

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

131

Shielding of the Target Area of the Fragment Separator Super-FRS  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

T. Radon; E. Kozlova; G. Fehrenbacher; H. Geissel; K. Sümmerer; H. Weick; M. Winkler

132

Evaluation of Radionuclides in Concrete Shielding for Nuclear Power Plant Decommissioning  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Decontamination/Decommissioning

Yen-Fu Chen; Yen-Kung Lin; Rong-Jiun Sheu; Shiang-Huei Jiang

133

Experimental Studies of Shielding and Irradiation Effects at High-Energy Accelerator Facilities  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

H. Nakashima; Y. Sakamoto; Y. Iwamoto; N. Matsuda; Y. Kasugai; Y. Nakane; F. Masukawa; N. V. Mokhov; A. F. Leveling; D. J. Boehnlein; K. Vaziri; T. Sanami; H. Matsumura; M. Hagiwara; H. Iwase; N. Kinoshita; H. Hirayama; K. Oishi; T. Nakamura; H. Arakawa; N. Shigyo; K. Ishibashi; H. Yashima; N. Nakao; K. Niita

134

Characteristics of Prompt Radiation Field and Shielding Design for Taiwan Photon Source  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

R. J. Sheu; J. Liu; J. P. Wang; K. K. Lin; G. H. Luo

135

Beam Dump and Local Shielding Layout Around the ITEP Radiation Test Facility  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Yury Titarenko; Viacheslav Batyaev; Alexey Titarenko; Michael Butko; Kirill Pavlov; Sergey Florya; Roman Tikhonov; Pavel Boyko; Alexey Kovalenko; Nikolai Sobolevsky; Vasily Anashin; Stepan Mashnik; Waclaw Gudowski; Nikolai Mokhov; Igor Rakhno

136

Monte Carlo Application in Shielding Design for an X-Ray Container/Vehicle Inspection System  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Junli Li; Shenjin Ming; Yanfeng Cao; Yanli Deng

137

Shielding Analysis for a 40-MeV Electron Linac Facility  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Kai Masuda; Toshiteru Kii; Hideaki Ohgaki; Heishun Zen; Tetsuo Yamazaki

138

Testing of a High-Density Concrete as Neutron Shielding Material  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Eduardo Gallego; Alfredo Lorente; Héctor René Vega-Carrillo

139

Shielding Calculations for the New Experimental Storage Ring for the Facility for Antiproton and Ion Research  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

K. Vogt; G. Fehrenbacher; A. Knapp; T. Radon

140

Biological Shield Design and Analysis of KIPT Accelerator-Driven Subcritical Facility  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection

Zhaopeng Zhong; Yousry Gohar

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Impact of the Detailed Fission Source Distribution on IRIS Shielding Analyses  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Fausto Franceschini; Bojan Petrovic

142

Criticality safety and shielding design issues in the development of a high-capacity cask for truck transport  

SciTech Connect

General Atomics (GA) will be submitting an application for certification to the US Nuclear Regulatory Commission (NRC) for the GA-4 and GA-9 Casks In 1992. The GA-4 and GA-9 Casks are high-capacity legal weight truck casks designed to transport light water reactor spent fuel assemblies. To maintain a capacity of four pressurized-water-reactor (PWR) spent fuel assemblies, the GA-4 Cask uses burnup credit as part of the criticality control for initial enrichments over 3.0 wt% U-235. Using the US Department of Energy (DOE) Burnup Credit Program as a basis, GA has performed burnup credit analysis which is included in the Safety Analysis Report for Packaging (SARP). The GA-9 Cask can meet the criticality safety requirements using the ``fresh fuel`` assumption. Our approach to shielding design is to optimize the GA-4 and GA-9 Cask shielding configurations for minimum weights and maximum payloads. This optimization involves the use of the most effective shielding material, square cross-section geometry with rounded corners and tapered neutron shielding sections in the non-fuel regions.

Boshoven, J.K.

1992-08-01T23:59:59.000Z

143

Criticality safety and shielding design issues in the development of a high-capacity cask for truck transport  

Science Conference Proceedings (OSTI)

General Atomics (GA) will be submitting an application for certification to the US Nuclear Regulatory Commission (NRC) for the GA-4 and GA-9 Casks In 1992. The GA-4 and GA-9 Casks are high-capacity legal weight truck casks designed to transport light water reactor spent fuel assemblies. To maintain a capacity of four pressurized-water-reactor (PWR) spent fuel assemblies, the GA-4 Cask uses burnup credit as part of the criticality control for initial enrichments over 3.0 wt% U-235. Using the US Department of Energy (DOE) Burnup Credit Program as a basis, GA has performed burnup credit analysis which is included in the Safety Analysis Report for Packaging (SARP). The GA-9 Cask can meet the criticality safety requirements using the fresh fuel'' assumption. Our approach to shielding design is to optimize the GA-4 and GA-9 Cask shielding configurations for minimum weights and maximum payloads. This optimization involves the use of the most effective shielding material, square cross-section geometry with rounded corners and tapered neutron shielding sections in the non-fuel regions.

Boshoven, J.K.

1992-01-01T23:59:59.000Z

144

Where are we and where are we going in reactor shielding  

SciTech Connect

Information on reactor shielding is presented concerning nuclear data in shielding calculations, analysis methods, water-cooled reactors, fast-breeder reactors, and fusion reactors.

Maienschein, F.C.

1977-01-01T23:59:59.000Z

145

Glossary Term - Atomic Number  

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

Particle Previous Term (Alpha Particle) Glossary Main Index Next Term (Avogadro's Number) Avogadro's Number Atomic Number Silver's atomic number is 47 The atomic number is equal to...

146

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

147

Radiolysis Concerns for Water Shielding in Fission Surface Power Applications  

Science Conference Proceedings (OSTI)

This paper presents an overview of radiolysis concerns with regard to water shields for fission surface power. A review of the radiolysis process is presented and key parameters and trends are identified. From this understanding of the radiolytic decomposition of water, shield pressurization and corrosion are identified as the primary concerns. Existing experimental and modeling data addressing concerns are summarized. It was found that radiolysis of pure water in a closed volume results in minimal, if any net decomposition, and therefore reduces the potential for shield pressurization and corrosion.

Schoenfeld, Michael P. [NASA Marshall Space Flight Center, ER24, MSFC, AL 35812 (United States); Anghaie, Samim [Innovative Space Power and Propulsion Institute, 800 SW Archer Rd. Bldg.554, P.O. Box 116502, University of Florida, Gainesville, FL 32611-6502 (United States)

2008-01-21T23:59:59.000Z

148

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

2011-09-20T23:59:59.000Z

149

An Experimental Shield Test Facility for the Development of Minimum Weight Shields for Compact Reactor Power Systems  

SciTech Connect

Discussions are given of the characteristics of fission-source plate, graphite reactor, and pool-type reactor facilities applicable to development studies of minimum weight shielding materials. Advantages of a proposed SNAP dual-purpose shielding facility are described in terms of a disk-shaped fission-source plate, reactor, and building. A program for the study of advanced shielding materials is discussed for materials and configuations to be evaluted with the fission-source plate, the testing of the prototype at high-power levels, and full-power tests on the actual reactor.

Tomlinson, R.L.

1959-08-07T23:59:59.000Z

150

Atomic Spectroscopy Data Center  

Science Conference Proceedings (OSTI)

Atomic Spectroscopy Data Center. Summary: ... Atomic Spectroscopy Data Webpage. End Date: ongoing. Lead Organizational Unit: physlab. Contact. ...

2013-06-06T23:59:59.000Z

151

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-

152

Optimal Magnetic Shield Design with Second–Order Cone ...  

E-Print Network (OSTI)

... 106-8569 Japan. (tsuchiya@sun312.ism.ac.jp). 1 ... In this paper, a real-world optimal magnetic shielding design problem which arises in the development of ...

153

Airflow Characteristics of Commonly Used Temperature Radiation Shields  

Science Conference Proceedings (OSTI)

The air temperature radiation shield is a key component in air temperature measurement in weather station networks; however, it is widely recognized that significant errors in the measured air temperature exist due to insufficient airflow past ...

X. Lin; Kenneth G. Hubbard; George E. Meyer

2001-03-01T23:59:59.000Z

154

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 Print One way to test models of the solar system's formation is to compare the isotopic abundances of the...

155

Innovative Heat Shield Structure Completed for Orion - Materials ...  

Science Conference Proceedings (OSTI)

Posted on: 3/1/2010 12:00:00 AM... Lockheed Martin announced on March 1 that it has completed fabrication of the world's largest heat shield structure.

156

Atomic magnetometer  

SciTech Connect

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

157

Cross section space shielding in double heterogeneous HTGR systems  

SciTech Connect

Collision probability methods using rational approximations for space shielding of cross sections in nuclear reactor codes allowing for one level of heterogeneity are first reviewed. A Dancoff factor for a cylindrical HTGR fuel pin with grain structure is then derived. A new simple method for cross section space shielding in a doubly heterogeneous HTGR system using collision probabilities and rational approximations is subsequently presented and calculations based on it are compared with calculations based on more elaborate methods. 39 references. (auth)

Stamatelatos, M.G.

1975-11-01T23:59:59.000Z

158

Radiation Shielding Options for the Affordable Fission Surface Power System  

SciTech Connect

The Affordable Fission Surface Power System (AFSPS) is a proposed power source for an outpost capable of housing six humans for up to six weeks on the lunar surface and emphasizes the design principles of low risk and affordability over high performance. The radiation shield is the most massive component of the reactor system and its effect on launch mass greatly affects the affordability of the AFSPS. Potential shielding materials include lithium hydride, enriched boron-10 carbide, water, borated water, beryllium, boron-doped beryllium and zirconium hydride. Zirconium hydride is the most effective neutron attenuator and also significantly attenuates gamma radiation, but at a significant mass penalty. The other neutron attenuating materials all require the addition of a tungsten layer to provide significant gamma attenuation. Based on neutron radiation alone, lithium hydride is the lightest of the potential attenuators, followed by water and borated water. When gamma radiation is also considered, the lithium hydride/tungsten shield is shown to be the lightest composite shield with a combined mass of 3246 kg, followed by the borated water/tungsten shield (3479 kg). The boron carbide/tungsten shield has a total mass of 4129 kg, but represents significantly less development risk.

Craft, Aaron E.; King, Jeffrey C. [Mining and Nuclear Engineering Department Missouri University of Science and Technology 222 Fulton Hall, 301 W. 14th Street Rolla, MO 65401(United States)

2009-03-16T23:59:59.000Z

159

Shielding from instantaneously and adiabatically applied potential wells in collisionless plasmas  

E-Print Network (OSTI)

Shielding from instantaneously and adiabatically applied potential wells in collisionless plasmas A shielding'' . Experiments demonstrate that when a test potential well is applied to a one-dimensional pure of shielding implicitly or explicitly assume such collisions. Yet it is well known that shielding in plasmas

California at Berkeley, University of

160

Effect of Aggregate Specification in Heavy Concrete for Fusion Reactor Shield on Neutron Dose Evaluation  

E-Print Network (OSTI)

Effect of Aggregate Specification in Heavy Concrete for Fusion Reactor Shield on Neutron Dose Evaluation

Murata, I; Takahashi, A

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Drip shield Structural Response to Rock Fall  

Science Conference Proceedings (OSTI)

The objective of this calculation is to determine areas over the drip shield (DS) top plate and side-walls where the residual stress values exceed 50% of Ti-7 yield strength. These areas will also be referred to as the damaged areas throughout this document. The scope of this document is limited to reporting the calculation results in terms of the damaged areas based on a chosen set of stress components. This calculation is intended for use in support of the preliminary design activities for the license application design of the DS. This calculation is associated with the DS design and was performed by the Waste Package and Components. AP-3.12Q, ''Design Calculations and Analyses'' is used to perform the calculation and develop the document. The DS is classified as a safety category item. Therefore, this calculation is subject to the Quality Assurance Requirements and Description. The information provided by the sketches attached to this calculation is that of the potential design of the type of DS considered in this calculation and provides the potential dimensions and materials for the DS design. The finite element (FE) calculation was performed by using the commercially available LS-DYNA Version (V)960 (Software Tracking Number [STN] 10300-960.1106-00, Ref. 7) FE code. The results of this calculation were evaluated using residual first principal stress. Subsequent analysis of areas determined by residual stresses have been reported in the results section of this document. The finite element mesh adequacy was determined based on the maximum stress intensity and maximum first principal stress. The current work processes and procedures for the control of the electronic management of data for this activity were conducted in accordance with AP-3.13Q, ''Design Control'' (Section 5.1.2).

Z. Ceylan

2004-04-01T23:59:59.000Z

162

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.

163

A Historically Significant Shield for In Vivo Measurements  

SciTech Connect

Due to the ubiquitous nature of ionizing radiation, in vivo measurement systems designed to measure low levels of radionuclides in people are usually enclosed within a high density shield. Lead, steel, earth, and water are just some of the materials that have been and are being used to shield the detectors from radiations of cosmic, atmospheric, and terrestrial origin. At many Department of Energy sites, the counting room shields are constructed of pre-world War II steel to reduce the background levels to achieve measurements with low minimum detectable activities (MDA). This is one example of what is commonly called low background steel in the in vivo industry vernacular. The name arises from the fact the steel was manufactured prior to the beginning of atmospheric testing of nuclear weapons in the 1940s. Consequently, the steel is not likely to be contaminated with fission or activation products from fallout. For high energy photons (600 keV shielding significantly reduces the background levels. This is the story "swords-to-plowshare" of the unique steel that now forms a shielded room used at the In Vivo Radioassay and Research Facility (IVRRF) in Richland, Washington.

Lynch, Timothy P.

2007-08-01T23:59:59.000Z

164

Shielded fluid stream injector for particle bed reactor  

DOE Patents (OSTI)

A shielded fluid-stream injector assembly is provided for particle bed reactors. The assembly includes a perforated pipe injector disposed across the particle bed region of the reactor and an inverted V-shaped shield placed over the pipe, overlapping it to prevent descending particles from coming into direct contact with the pipe. The pipe and shield are fixedly secured at one end to the reactor wall and slidably secured at the other end to compensate for thermal expansion. An axially extending housing aligned with the pipe and outside the reactor and an inline reamer are provided for removing deposits from the inside of the pipe. The assembly enables fluid streams to be injected and distributed uniformly into the particle bed with minimized clogging of injector ports. The same design may also be used for extraction of fluid streams from particle bed reactors.

Notestein, J.E.

1991-12-31T23:59:59.000Z

165

Shielding of a hadron in a finite e-beam  

SciTech Connect

The thorough study of coherent electron cooling, the modern cooling technique capable to deal with accelerators operating in the range of few TeVs, rises many interesting questions. One of them is a shielding dynamics of a hadron in an electron beam. Now this effect is computed analytically in the infinite beam approximation. Many effects are drastically different in finite and infinite plasmas. Here we propose a method to compute the dynamical shielding effect in a finite cylindrical plasma - the realistic model of an electron beam in accelerators.

Elizarov A.; Litvinenko, V.; Wang, G.

2012-05-20T23:59:59.000Z

166

Monte Carlo Calculations for the Shielding Design of Beam Injection and Extraction Areas at the 3-GeV Synchrotron in J-PARC  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Accelerators

Yoshihiro Nakane; Teruo Abe; Hiroshi Nakashima

167

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

168

Shielding and Build-up Considerations for Radiation Detection  

SciTech Connect

Abstract -- Shielding for gamma radiation has traditionally focused on the reduction of dose effects. For these applications, reducing the energy of the radiation is important along with reducing the actual number of photons, and therefore large masses of high Z material are typically used. However, for measurements requiring low backgrounds or for detecting low activity signals, such as in homeland security applications, the primary use of shielding is to decrease the total number of background photons (perhaps in a region of interest), and therefore the processes of buildup and down scattering become important. In these applications, where the important measure is count rate instead of dose and low background are important, improved reduction in counts from background radiation may be achieved with specially designed configurations of thin layers of different materials instead of a single thick layer. This paper briefly describes recent modeling and experimental investigations in layered-shielding methodology and provides results with comparison to single shielding material such as Pb. Application of these techniques to some real world problems, such as detector systems for homeland security, is discussed.

Ely, James H.; Kernan, Warnick J.; Kouzes, Richard T.; Siciliano, Edward R.

2008-10-19T23:59:59.000Z

169

RZ calculations for self shielded multigroup cross sections  

Science Conference Proceedings (OSTI)

A collision probability method has been implemented for RZ geometries. The method accounts for white albedo, specular and translation boundary condition on the top and bottom surfaces of the geometry and for a white albedo condition on the outer radial surface. We have applied the RZ CP method to the calculation of multigroup self shielded cross sections for Gadolinia absorbers in BWRs. (authors)

Li, M.; Sanchez, R.; Zmijarevic, I.; Stankovski, Z. [Commissariat a l'Energie Atomique CEA, Direction de l'Energie Nucleaire, DEN/DM2S/SERMA/LENR, 91191 Gif-sur-Yvette Cedex (France)

2006-07-01T23:59:59.000Z

170

Multi electron species and shielding potentials in plasmas  

SciTech Connect

The phenomenon of Debye shielding is investigated in electron ion plasmas using the approach of two temperature electrons. We get different profiles of potential for different parameters and observe that the potentials fall very slowly than the standard Coulomb and Debye potentials. The importance of work is pointed out in the introduction.

Khan, Arroj A.; Murtaza, G. [Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Rasheed, A.; Jamil, M. [Department of Physics, Government College University, Faisalabad 38000 (Pakistan)

2012-11-15T23:59:59.000Z

171

Electromechanical coupling model for cutterhead driving system of shield machines  

Science Conference Proceedings (OSTI)

The synchronization of the cutterhead driving system of shield machines is affected by not only the nonlinearity of mechanical transmission mechanism and the characteristics of driving motors, but also their interaction. In this paper, dynamics of the ... Keywords: cutterhead, electromechanical coupling, synchronization

Jianzhong Sun; Ran Liu; Yaqin Luo; Wei Sun

2010-11-01T23:59:59.000Z

172

Monte Carlo Simulations for the Shielding of the Collector Ring and the Recycled Experimental Storage Ring at FAIR  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Alexandra Knapp; Torsten Radon; Karsten Vogt; Georg Fehrenbacher

173

Concrete Shield Performance of the VSC-17 Spent Nuclear Fuel Cask  

Science Conference Proceedings (OSTI)

The VSC-17 Spent Nuclear Fuel Storage Cask was surveyed for degradation of the concrete shield by radiation measurement, temperature measurement, and ultrasonic testing. No general loss of shielding function was identified.

Koji Shirai

2006-04-01T23:59:59.000Z

174

12/16/03 1/21/04 Cable Management and Shielding  

Science Conference Proceedings (OSTI)

... 12/16/03 1/21/04 Cable Management and Shielding. ... The aperture plug installed in the shield wall and the 1 inch insert on the outer optical bench. ...

175

IMRT treatment of anal cancer with a scrotal shield  

SciTech Connect

The risk of sterility in males undergoing radiotherapy in the pelvic region indicates the use of a shielding device, which offers protection to the testes for patients wishing to maintain fertility. The use of such devices in the realm of intensity-modulated radiotherapy (IMRT) in the pelvic region can pose many obstacles during simulation, treatment planning, and delivery of radiotherapy. This work focuses on the development and execution of an IMRT plan for the treatment of anal cancer using a scrotal shielding device on a clinical patient. An IMRT plan was developed using Eclipse treatment planning system (Varian Medical Systems, Palo Alto, CA), using a wide array of gantry angles as well as fixed jaw and fluence editing techniques. When possible, the entire target volume was encompassed by the treatment field. When the beam was incident on the scrotal shield, the jaw was fixed to avoid the device and the collimator rotation optimized to irradiate as much of the target as possible. This technique maximizes genital sparing and allows minimal irradiation of the gonads. When this fixed-jaw technique was found to compromise adequate coverage of the target, manual fluence editing techniques were used to avoid the shielding device. Special procedures for simulation, imaging, and treatment verification were also developed. In vivo dosimetry was used to verify and ensure acceptable dose to the gonads. The combination of these techniques resulted in a highly conformal plan that spares organs and risk and avoids the genitals as well as entrance of primary radiation onto the shielding device.

Hood, Rodney C., E-mail: Rodney.Hood@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Wu, Q. Jackie; McMahon, Ryan; Czito, Brian; Willett, Christopher [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States)

2012-01-01T23:59:59.000Z

176

Shielding measurements for a 230 MeV proton beam  

SciTech Connect

Energetic secondary neutrons produced as protons interact with accelerator components and patients dominate the radiation shielding environment for proton radiotherapy facilities. Due to the scarcity of data describing neutron production, attenuation, absorbed dose, and dose equivalent values, these parameters were measured for 230 MeV proton bombardment of stopping length Al, Fe, and Pb targets at emission angles of 0{degree}, 22{degree}, 45{degree}, and 90{degree} in a thick concrete shield. Low pressure tissue-equivalent proportional counters with volumes ranging from 1 cm{sup 3} to 1000 cm{sup 3} were used to obtain microdosimetric spectra from which absorbed dose and radiation quality are deduced. Does equivalent values and attenuation lengths determined at depth in the shield were found to vary sharply with angle, but were found to be independent of target material. Neutron dose and radiation length values are compared with Monte Carlo neutron transport calculations performed using the Los Alamos High Energy Transport Code (LAHET). Calculations used 230 MeV protons incident upon an Fe target in a shielding geometry similar to that used in the experiment. LAHET calculations overestimated measured attenuation values at 0{degree}, 22{degree}, and 45{degree}, yet correctly predicted the attenuation length at 90{degree}. Comparison of the mean radiation quality estimated with the Monte Carlo calculations with measurements suggest that neutron quality factors should be increased by a factor of 1.4. These results are useful for the shielding design of new facilities as well as for testing neutron production and transport calculations.

Siebers, J.V.

1990-01-01T23:59:59.000Z

177

Flood and Shield Basalts from Ethiopia: Magmas from the African Superswell  

E-Print Network (OSTI)

-known, but less well-preserved, flood basalt provinces such as the Deccan and Karoo. The shield volcanoes have

Demouchy, Sylvie

178

BSA 02-23: Delivering Shielded Electron Beams to a Target in a ...  

The apparatus includes a plasma generator aligned with a beam generator for producing plasma to shield an energized beam.

179

Reduced Loss in Precipitation Measurements Using a New Wind Shield for Raingages  

Science Conference Proceedings (OSTI)

A problem of great concern in precipitation measurements is the wind loss. This paper presents a new wind shield that reduces this loss. Tests of the new shield were made in a wind tunnel and in the field. The wind shield consisted of a flange ...

Anders Lindroth

1991-06-01T23:59:59.000Z

180

Using exotic atoms to keep borders safe  

Science Conference Proceedings (OSTI)

Muons, created by a particle accelerator, can be used to scan cargo for special nuclear materials (SNM). These muons exist long enough and are penetrating enough that they can be used to actively scan cargo to ensure the non-proliferation of SNM. A set of 'proof-of-concept' experiments have been performed to show that active muon analysis can be used. Experiments were performed at high intensity, medium energy particle accelerators (TRIUMF and PSI). Negative muons form exotic atoms with one electron replaced by the muon. Since the muon is captured in an excited state, it will give off x-rays which can be detected by high purity germanium detectors. These characteristic x-rays can be used to identify the nuclide. The muonic x-rays corresponding to the SNM of interest have been measured, even with the use of various shielding configurations composed of lead, iron, polyethylene, or fiberglass. These preliminary results show that muons can be successfully used to find shielded SNM. The safety of North Americans can be protected by the use of this technology.

Jason, A [Los Alamos National Laboratory; Miyadera, H [Los Alamos National Laboratory; Esch, E I [Los Alamos National Laboratory; Hoteling, N J [Los Alamos National Laboratory; Adelmann, A [Los Alamos National Laboratory; Heffner, R H [Los Alamos National Laboratory; Green, A [NON LANL; Olsthoorn, J [NON LANL; Stocki, T J [NON LANL

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

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.

182

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

183

Shielding of mirror FERF plasma by arc discharges  

SciTech Connect

The feasibility of shielding a mirror-confined fusion plasma against erosion by incident neutrals with a plasma blanket generated by an array of hollow-cathode arc discharges was studied. Such a plasma blanket could also be used for linetying stabilization of a single mirror confined plasma as well as to provide a warm plasma stream for stabilization of microinstabilities. The requirements for the plasma blanket are dependent on the parameter ..gamma.., the ratio of the actual cross-field diffusion coefficient to the classical value. The power requirement compares favorably with power loss due to change exchange without shielding. More importantly, the blanket permits a relaxation of vacuum requirements to prevent erosion of the hot plasma by background neutrals.

Woo, J.T.

1976-12-08T23:59:59.000Z

184

SEU43 fuel bundle shielding analysis during spent fuel transport  

Science Conference Proceedings (OSTI)

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

185

Special concrete shield selection using the analytic hierarchy process  

SciTech Connect

Special types of concrete radiation shields that depend on locally available materials and have improved properties for both neutron and gamma-ray attenuation were developed by using plastic materials and heavy ores. The analytic hierarchy process (AHP) is implemented to evaluate these types for selecting the best biological radiation shield for nuclear reactors. Factors affecting the selection decision are degree of protection against neutrons, degree of protection against gamma rays, suitability of the concrete as building material, and economic considerations. The seven concrete alternatives are barite-polyethylene concrete, barite-polyvinyl chloride (PVC) concrete, barite-portland cement concrete, pyrite-polyethylene concrete, pyrite-PVC concrete, pyrite-portland cement concrete, and ordinary concrete. The AHP analysis shows the superiority of pyrite-polyethylene concrete over the others.

Abulfaraj, W.H. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Nuclear Engineering Dept.)

1994-08-01T23:59:59.000Z

186

Accordian-folded boot shield for flexible swivel connection  

DOE Patents (OSTI)

A flexible swivel boot connector for connecting a first boot shield section to a second boot shield section, both first and second boot sections having openings therethrough, the second boot section having at least two adjacent accordian folds at the end having the opening, the second boot section being positioned through the opening of the first boot section such that a first of the accordian folds is within the first boot section and a second of the accordian folds is outside of the first boot, includes first and second annular discs, the first disc being positioned within and across the first accordian fold, the second disc being positioned within and across the second accordian fold, such that the first boot section is moveably and rigidly connected between the first and second accordian folds of the second boot section.

Hoh, Joseph C. (Naperville, IL)

1986-01-01T23:59:59.000Z

187

Secret key distillation from shielded two-qubit states  

Science Conference Proceedings (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.

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

2010-05-15T23:59:59.000Z

188

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

189

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 that was 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 used in the construction of the packaging, followed by polyvinyl acetate (PVAc) glue. Fiberboard material, also used in the construction of the packaging induced corrosion to a much lesser extent than the PVAc glue and RTV sealant, and only in the presence of condensed water. The results indicated faster corrosion at temperatures higher than ambient and with condensed water. In light of these corrosion mechanisms, the lead shielding was sheathed in a stainless steel liner to mitigate against corrosion.

Subramanian, K; Kerry Dunn, K; Joseph Murphy, J

2008-07-18T23:59:59.000Z

190

Atomic and Molecular Physics  

Science Conference Proceedings (OSTI)

... DG, * SRD 105 Physic Laboratory's Elemental ... Nuclear Physics SRD 144 Atomic Weights & ... Physical Constants SRD 121 Fundamental Physical ...

2012-10-10T23:59:59.000Z

191

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

192

Calibrated Atomic Force Microscopy  

Science Conference Proceedings (OSTI)

... Vorburger, SL Tan, NG Orji, J. Fu, “Interlaboratory Comparison of Traceable Atomic Force Microscope Pitch Measurements,” SPIE Proceedings Vol. ...

2011-10-28T23:59:59.000Z

193

Dynamic magnetic shield for the CLAS12 central TOF detector photomultiplier tubes  

SciTech Connect

The Central Time-of-Flight detector for the Jefferson Laboratory 12-GeV upgrade is being designed with linear-focused photomultiplier tubes that require a robust magnetic shield against the CLAS12 main 5-T solenoid fringe fields of 100 mT (1 kG). Theoretical consideration of a ferromagnetic cylinder in an axial field has demonstrated that its shielding capability decreases with increasing length. This observation has been confirmed with finite element analysis using Poisson model software. Several shields composed of coaxial ferromagnetic cylinders have been studied. All difficulties caused by saturation effects were overcome with a novel dynamical shield, which utilizes a demagnetizing solenoid between the shielding cylinders. Basic dynamical shields for ordinary linear-focused 2-in. photomultiplier tubes were designed and tested both with models and experimental prototypes at different external field and demagnetizing current values. Our shield design reduces the 1 kG external axial field by a factor of 5000.

V. Baturin, V. Burkert, D.S. Carman, L. Elouadrhyri, D. Grilli, D. Kashy, E. Pasyuk, L. Quettier, B. Wieland

2012-02-01T23:59:59.000Z

194

Thermal Analysis of a SHIELD Electromigration Test Structure  

Science Conference Proceedings (OSTI)

The steady state and transient thermal behavior of an electromigration test structure was analyzed. The test structure was a Sandia SHIELD (Self-stressing HIgh fregquency rELiability Device) electromigration test device manufactured by an outside vendor. This device has a high frequency oscillator circuit, a buffer circuit to isolate and drive the metal line to the tested (DUT), the DUT to be electromigrated itself, a metal resistance thermometry monitor, and a heater elment to temperature accelerate the electromigration effect.

Benson, David A.; Bowman, Duane J.; Mitchell, Robert T.

1999-05-01T23:59:59.000Z

195

A STUDY OF THE PRIMARY SHIELD FOR THE PRDC REACTOR  

SciTech Connect

Temperature distributions, irradiation effects, stacking arrangements, voidage, and economics for the borated-graphite shield of the PRDC reactor were investigated. Of the shield systems considered, four are reported here. System 1 contalns 30 in. of 1% borated graphite, with either ordinary graphite or a cement as a filler for the remaindcr of the volume. The maximum temperature at the flex plates in this system was calculated to be 5OO deg F. Systems 2 and 3 consist of 2 in. of 5% borated graphite near the core vessel and 1/2 in. of Boral at the primary-shield tank. A filler material of carbon blocks is used in System 2 and graphite in System 3. The calculated maximum temperatures were 700 deg F and 35O deg F, respectively. System 4 consists of a laminated structure of Boral and graphite near the primary-shield tank and carbon-block filler. It was calculated to have a maximum temperature of 600 deg F at the flex plates. The maximum temperature at the flex plates recommended by APDA is 500 deg F. Energy storage and radiation damage were found to be within permissible limits in all four systems. However, these conclusions are based on experimental data from the Hanford reactor in which the neutron-energy spectrum differs considerably from the PRDC spectrum. A porosity of less than 740 cu ft is required in order that a sodium leak from the core vessel does not expose the core. The voidages in any of the systems mentioned above is about 400 cu ft excluding absorption effects. these are believed to be small. The systems coataining Boral were found to be less expensive than the ones using only borated graphite. Over-all material costs range between 0,000 for Boral systems and 0,000 for borated- graphite systems. (auth)

Epstein, H.M.; Dingee, D.A.; Chastain, J.W.

1957-04-15T23:59:59.000Z

196

Identification of Shielding Material Configurations Using NMIS Imaging  

Science Conference Proceedings (OSTI)

The Nuclear Materials Identification System (NMIS) uses fast neutron tomographic imaging to nonintrusively examine the interior structure of shielded objects. The pixel values in such images represent the attenuation coefficients of the time- and directionally-tagged fast neutrons from a deuterium-tritium (D T) neutron generator. The reconstruction techniques use either a filtered back projection or a maximum likelihood expectation maximization algorithm. As a first test of the capabilities of these reconstruction techniques to correctly identify individual parts inside of an object, fast neutron imaging was used to identify the regions of shielding surrounding a depleted uranium casting from a library of possible parts. The shielding consisted of multiple regions of common materials such as steel, lead, aluminum, and polyethylene. First, the full object was imaged, and then each of the individual parts was imaged. Several additional parts that were not present in the original object were also imaged to form a library. The individual parts were compared to the full object, and the correct ones were identified using three different methods. These methods included a visual match, an iterative fit of each part, and a mathematical test comparing the sum of squared errors. The successful results demonstrate an initial application of matching. This suggests that it should be possible to implement more sophisticated matching techniques using automated pixel-by-pixel comparison methods in the future.

Grogan, Brandon R [ORNL; Mihalczo, John T [ORNL; McConchie, Seth M [ORNL; Mullens, James Allen [ORNL

2011-01-01T23:59:59.000Z

197

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

198

Thermal-Structural Design of a Water Shield For Surface Reactor Missions  

SciTech Connect

Water shielding is an attractive option for an affordable lunar surface fission reactor program. The attractiveness of the water shielding option arises from the relative ease of proto-typing and ground testing, the relatively low development effort needed, as well as the fabrication and operating experience with stainless steel and water. The most significant limitation in using a water shield is temperature: to prevent the formation of voids and the consequent loss of cooling, the water temperature has to be maintained below the saturation temperature corresponding to the shield pressure. This paper examines natural convection for a prototypic water shield design using the computational fluid dynamics (CFD) code CFX-5 as well as analytical modeling. The results show that natural convection is adequate to keep the water well-mixed. The results also show that for the above-ground configuration, shield surface and water temperatures during lunar day conditions are high enough to require shield pressures up to 2.5 atm to prevent void formation. For the buried configuration, a set of ammonia heat pipes attached to the shield outer wall can be used to maintain water temperatures within acceptable limits. Overall the results show that water shielding is feasible for lunar surface applications. The results of the CFD analyses can also be used to guide development of testing plans for shield thermal testing. (authors)

Sadasivan, Pratap; Kapernick, Richard J.; Poston, David I. [D-5 Nuclear Systems Design Group MS K575, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545 (United States)

2006-07-01T23:59:59.000Z

199

Atomic Data for Mercury (Hg)  

Science Conference Proceedings (OSTI)

... Mercury (Hg) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Mercury (Hg). ...

200

Atomic Data for Plutonium (Pu)  

Science Conference Proceedings (OSTI)

... Plutonium (Pu) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Plutonium (Pu). ...

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Atomic Data for Uranium (U )  

Science Conference Proceedings (OSTI)

... Uranium (U) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Uranium (U). ...

202

Atomic Data for Thorium (Th)  

Science Conference Proceedings (OSTI)

... Thorium (Th) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Thorium (Th). ...

203

Atomic Data for Hydrogen (H )  

Science Conference Proceedings (OSTI)

... Hydrogen (H) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Hydrogen (H). ...

204

Atomic Data for Tungsten (W )  

Science Conference Proceedings (OSTI)

... Tungsten (W) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Tungsten (W). ...

205

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.

206

Metal atom oxidation laser  

DOE Patents (OSTI)

A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides. (auth)

Jensen, R.J.; Rice, W.W.; Beattie, W.H.

1975-10-28T23:59:59.000Z

207

Metal atom oxidation laser  

DOE Patents (OSTI)

A chemical laser which operates by formation of metal or carbon atoms and reaction of such atoms with a gaseous oxidizer in an optical resonant cavity is described. The lasing species are diatomic or polyatomic in nature and are readily produced by exchange or other abstraction reactions between the metal or carbon atoms and the oxidizer. The lasing molecules may be metal or carbon monohalides or monoxides.

Jensen, R.J.; Rice, W.W.; Beattie, W.H.

1975-10-28T23:59:59.000Z

208

Early Test Facilities and Analytic Methods for Radiation Shielding  

SciTech Connect

This report represents a compilation of eight papers presented at the 1992 American Nuclear Society/European Nuclear Society International Meeting held in Chicago, Illinois on November 15 20,1992. The meeting is of special significance since it commemorates the 50th anniversary of the first controlled nuclear chain reaction, which occurred, not coincidentally, in Chicago. 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.

Ingersoll, D.T.

1992-01-01T23:59:59.000Z

209

Rapid emission angle selection for rotating-shield brachytherapy  

SciTech Connect

Purpose: The authors present a rapid emission angle selection (REAS) method that enables the efficient selection of the azimuthal shield angle for rotating shield brachytherapy (RSBT). The REAS method produces a Pareto curve from which a potential RSBT user can select a treatment plan that balances the tradeoff between delivery time and tumor dose conformity. Methods: Two cervical cancer patients were considered as test cases for the REAS method. The RSBT source considered was a Xoft Axxent{sup TM} electronic brachytherapy source, partially shielded with 0.5 mm of tungsten, which traveled inside a tandem intrauterine applicator. Three anchor RSBT plans were generated for each case using dose-volume optimization, with azimuthal shield emission angles of 90 Degree-Sign , 180 Degree-Sign , and 270 Degree-Sign . The REAS method converts the anchor plans to treatment plans for all possible emission angles by combining neighboring beamlets to form beamlets for larger emission angles. Treatment plans based on exhaustive dose-volume optimization (ERVO) and exhaustive surface optimization (ERSO) were also generated for both cases. Uniform dwell-time scaling was applied to all plans such that that high-risk clinical target volume D{sub 90} was maximized without violating the D{sub 2cc} tolerances of the rectum, bladder, and sigmoid colon. Results: By choosing three azimuthal emission angles out of 32 potential angles, the REAS method performs about 10 times faster than the ERVO method. By setting D{sub 90} to 85-100 Gy{sub 10}, the delivery times used by REAS generated plans are 21.0% and 19.5% less than exhaustive surface optimized plans used by the two clinical cases. By setting the delivery time budget to 5-25 and 10-30 min/fx, respectively, for two the cases, the D{sub 90} contributions for REAS are improved by 5.8% and 5.1% compared to the ERSO plans. The ranges used in this comparison were selected in order to keep both D{sub 90} and the delivery time within acceptable limits. Conclusions: The REAS method enables efficient RSBT treatment planning and delivery and provides treatment plans with comparable quality to those generated by exhaustive replanning with dose-volume optimization.

Liu, Yunlong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Sun, Wenqing [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Yang Wenjun [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa 52242 (United States); Wu Xiaodong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

2013-05-15T23:59:59.000Z

210

Atomic Spectroscopy: An Introduction  

Science Conference Proceedings (OSTI)

... 60. A. de-Shalit and I. Talmi, Nuclear Shell Theory (Academic, New York, 1963). ... CE Moore, Atomic Energy Levels, Natl. Stand. Ref. ...

211

NIST Atomic Spectra Database  

Science Conference Proceedings (OSTI)

... Ground states and ionization energies of atoms ... the US Department of Energy, by the ... SRDP), and by NIST's Systems Integration for Manufacturing ...

2013-09-12T23:59:59.000Z

212

Cold Atoms News  

Science Conference Proceedings (OSTI)

... the first time caused a gas of atoms ... mysterious data in ultracold gases of rubidium ... Material May Demonstrate Long-Sought 'Liquid' Magnetic State ...

2010-10-20T23:59:59.000Z

213

The Harnessed Atom  

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

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,...

214

Atomic Collapse Observed  

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

Collapse State Observed Aided by Simulations, Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 |...

215

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

216

Shielding Calculations for the Hard X-Rays Generated by LCLS MEC Laser System  

Science Conference Proceedings (OSTI)

Technical Paper / Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Radiation Transport and Protection

R. Qiu; J. C. Liu; S. H. Rokni; A. A. Prinz

217

Numerical Simulation of Earth Pressure on Head Chamber of Shield Machine with FEM  

SciTech Connect

Model parameters of conditioned soils in head chamber of shield machine are determined based on tree-axial compression tests in laboratory. The loads acting on tunneling face are estimated according to static earth pressure principle. Based on Duncan-Chang nonlinear elastic constitutive model, the earth pressures on head chamber of shield machine are simulated in different aperture ratio cases for rotating cutterhead of shield machine. Relationship between pressure transportation factor and aperture ratio of shield machine is proposed by using aggression analysis.

Li Shouju; Kang Chengang [State Key Laboratory of structural analysis for industrial equipment, Dalian University of Technology, Dalian 116023 (China); Sun, Wei [School of Mechanical Engineering, Dalian University of Technology, Dalian 116023 (China); Shangguan Zichang [School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116023 (China); Institute of Civil Engineering, Dalian Fishery University, Dalian 116023 (China)

2010-05-21T23:59:59.000Z

218

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

219

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 deg. C. The CFD model with 1/6-g predicts a maximum water temperature of 88 deg. 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.

Pearson, J. Boise; Stewart, Eric T. [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Reid, Robert S. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States)

2007-01-30T23:59:59.000Z

220

Electrically shielded enclosure with magnetically retained removable cover  

DOE Patents (OSTI)

Disclosed is an electrically shielded enclosure having electrical components therein and a removable electrically shielded cover over an opening in the enclosure with a magnetic securement mechanism provided to removably secure the cover to the enclosure in a manner which will provide easy access, yet also provide an electrical seal between the cover and the enclosure capable of preventing the passage of electrical radiation through the joint between the cover and the enclosure. Magnets are provided on the enclosure peripherally around the opening and facing the cover, and a ferromagnetic surface is provided on the mating surface of the cover facing the magnets, with a continuous electrical seal provided between the magnets and the ferromagnetic surface on the cover to prevent the leakage of electromagnetic radiation therethrough. In one embodiment the electrical seal includes a flexible metal casing or surface, which is attached to the enclosure and positioned between the magnets and the ferromagnetic surface on the cover, and which is sufficiently flexible to be capable of conforming to the ferromagnetic surface to provide an electrical seal between the cover and the enclosure. In another embodiment, the electrical seal includes a metal mesh associated with the enclosure and positioned between the magnets on the enclosure and the ferromagnetic surface on the cover. The metal mesh is also capable of conforming to the surface of the ferromagnetic surface to thereby provide an electrical seal between the cover and the enclosure.

Rivers, Craig J. (Livermore, CA); Lee, Roanne A. (San Francisco, CA); Jones, Glenn E. (Livermore, CA)

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

A NOTE ON IMPORTANCE FUNCTIONS FOR THE SHIELDING OF MANNED SPACE VEHICLES  

SciTech Connect

The tissue dose calculations of Kinney were used to calculate several importance functions associated with the dose from primary and secondary particles in the tissue due to penetration of an aluminum shield by a solar-flare proton spectrum. Secondary particles produced in the shield were not considered. (auth)

Alsmiller, R.G. Jr.

1964-03-01T23:59:59.000Z

222

Neutron and gamma radiation shielding material, structure, and process of making structure  

DOE Patents (OSTI)

The present invention is directed to a novel neutron and gamma radiation shielding material consisting of 95 to 97% by weight SiO/sub 2/ and 5 to 3% by weight sodium silicate. In addition, the method of using this composition to provide a continuous neutron and gamma radiation shielding structure is disclosed.

Hondorp, H.L.

1981-07-06T23:59:59.000Z

223

Materials' Deformation Dynamics at Atomic Scale In situ Atomic ...  

Science Conference Proceedings (OSTI)

Presentation Title, Materials' Deformation Dynamics at Atomic Scale In situ Atomic .... What Can We Learn from Measurements of Li-ion Battery Single Particles?

224

Shielding considerations for advanced space nuclear reactor systems  

SciTech Connect

To meet the anticipated future space power needs, the Los Alamos National Laboratory is developing components for a compact, 100 kW/sub e/-class heat pipe nuclear reactor. The reactor uses uranium dioxide (UO/sub 2/) as its fuel, and is designed to operate around 1500 k. Heat pipes are used to remove thermal energy from the core without the use of pumps or compressors. The reactor heat pipes transfer mal energy to thermoelectric conversion elements that are advanced versions of the converters used on the enormously successful Voyager missions to the outer planets. Advanced versions of this heat pipe reactor could also be used to provide megawatt-level power plants. The paper reviews the status of this advanced heat pipe reactor and explores the radiation environments and shielding requirements for representative manned and unmanned applications.

Angelo, J.P. Jr.; Buden, D.

1982-01-01T23:59:59.000Z

225

Method for fabricating fan-fold shielded electrical leads  

DOE Patents (OSTI)

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.

Rohatgi, Rajeev R. (Mountain View, CA); Cowan, Thomas E. (Livermore, CA)

1994-01-01T23:59:59.000Z

226

Method for fabricating fan-fold shielded electrical leads  

DOE Patents (OSTI)

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 figures.

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

1994-12-27T23:59:59.000Z

227

Underground barrier construction apparatus with soil-retaining shield  

DOE Patents (OSTI)

An apparatus for building a horizontal underground barrier by cutting through soil and depositing a slurry, preferably one which cures into a hardened material. The apparatus includes a digging means for cutting and removing soil to create a void under the surface of the ground, a shield means for maintaining the void, and injection means for inserting barrier-forming material into the void. In one embodiment, the digging means is a continuous cutting chain. Mounted on the continuous cutting chain are cutter teeth for cutting through soil and discharge paddles for removing the loosened soil. This invention includes a barrier placement machine, a method for building an underground horizontal containment barrier using the barrier placement machine, and the underground containment system. Preferably the underground containment barrier goes underneath and around the site to be contained in a bathtub-type containment.

Gardner, Bradley M. (Idaho Falls, ID); Smith, Ann Marie (Pocatello, ID); Hanson, Richard W. (Spokane, WA); Hodges, Richard T. (Deer Park, WA)

1998-01-01T23:59:59.000Z

228

Estimation of the Performance of Multiple Active Neutron Interrogation Signatures for Detecting Shielded HEU  

SciTech Connect

A comprehensive modeling study has been carried out to evaluate the utility of multiple active neutron interrogation signatures for detecting shielded highly enriched uranium (HEU). The modeling effort focused on varying HEU masses from 1 kg to 20 kg; varying types of shields including wood, steel, cement, polyethylene, and borated polyethylene; varying depths of the HEU in the shields, and varying engineered shields immediately surrounding the HEU including steel, tungsten, and cadmium. Neutron and gamma-ray signatures were the focus of the study and false negative detection probabilities versus measurement time were used as a performance metric. To facilitate comparisons among different approaches an automated method was developed to generate receiver operating characteristic (ROC) curves for different sets of model variables for multiple background count rate conditions. This paper summarizes results or the analysis, including laboratory benchmark comparisons between simulations and experiments. The important impact engineered shields can play towards degrading detectability and methods for mitigating this will be discussed.

David L. Chichester; Scott J. Thompson; Scott M. Watson; James T. Johnson; Edward H. Seabury

2012-10-01T23:59:59.000Z

229

Penetration of the LCLS Injector Shield Wall at Sector 20  

SciTech Connect

Penetrations through the LCLS injector shield wall are needed for the alignment of the accelerator, a diagnostic laser beam and utilities, and are shown in figure 1. The 1-inch diameter LCLS injector beam tube is blocked by the PPS stopper when the injector side of the wall is occupied. The two 3-inch diameter penetrations above and to the left of the beam tube are used by Precision Alignment and will be open only during installation of the injector beamline. Additional 3-inch diameter penetrations are for laser beams which will be used for electron beam diagnostics. These will not be plugged when the injector occupied. Other penetrations for the RF waveguide and other utilities are approximately 13-inch from the floor and as such are far from the line-of-sight of any radiation sources. The waveguide and utility penetrations pass only through the thicker wall as shown in the figure. The principal issue is with the two laser penetrations, since these will be open when the linac is operating and people are in the LCLS injector area. A principal concern is radiation streaming through the penetrations due to direct line-of sight of the PEP-2 lines. To answer this, fans of rays were traced through the 3-inch diameter laser penetrations as shown in Figures 2 and 3. Figure 2 gives the top view of the shield walls, the main linac and PEP-2 lines, and the ray-fans. The fans appear to originate between the walls since their angular envelope is defined by the greatest angle possible when rays are just on the 3-inch diameter at the inner most and outermost wall surfaces. The crossovers of all possible rays lie half way between these two surfaces. As the end-on view of Figure 3 clearly shows, there is no direct line-of-sight through the laser penetrations of the PEP-2 or linac beamlines.

Dowell, D

2010-12-10T23:59:59.000Z

230

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

231

general_atomics.cdr  

Office of Legacy Management (LM)

from the U.S. Department of Energy (DOE). Discussions between DOE and General Atomics led to an agreed cost-sharing and no-fee arrangement for the decontamination and site...

232

Shielding Benchmark Calculations with SCALE/MAVRIC and Comparison with Measurements for the German Cask CASTOR® HAW 20/28 CG  

Science Conference Proceedings (OSTI)

Shielding / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Protection

H. Thiele; F.-M. Börst

233

Sharing the atom bomb  

Science Conference Proceedings (OSTI)

Shaken by the devastation of Hiroshima and Nagasaki and fearful that the American atomic monopoly would spark an arms race, Dean Acheson led a push in 1946 to place the bomb-indeed, all atomic energy-under international control. But as the memories of wartime collaboration faded, relations between the superpowers grew increasingly tense, and the confrontational atmosphere undid his proposal. Had Acheson succeeded, the Cold War might not have been. 2 figs.

Chace, J.

1996-01-01T23:59:59.000Z

234

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.

Huxford, Theodore J. (Harriman, TN)

1993-01-01T23:59:59.000Z

235

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

236

Effects of atomic radiation  

SciTech Connect

This book focuses on the lifelong effects of atomic radiation exposure in language understandable by the concerned layperson or the specialist in another field. The base of knowledge used is the work of the Atomic Bomb Casualty Commission and its successor since 1975 the Radiation Effects Research Foundation. Within the range of Chronic effects on human health the book provides a thorough review, although effects of nonionizing radiation, effects on structures, effects on other living species, and acute effects are not discussed.

Schull, W.J.

1995-12-31T23:59:59.000Z

237

Atomizing nozzle and method  

DOE Patents (OSTI)

A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

Ting, Jason (Ames, IA); Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

2000-03-16T23:59:59.000Z

238

Adaptive planning using megavoltage fan-beam CT for radiation therapy with testicular shielding  

Science Conference Proceedings (OSTI)

This study highlights the use of adaptive planning to accommodate testicular shielding in helical tomotherapy for malignancies of the proximal thigh. Two cases of young men with large soft tissue sarcomas of the proximal thigh are presented. After multidisciplinary evaluation, preoperative radiation therapy was recommended. Both patients were referred for sperm banking and lead shields were used to minimize testicular dose during radiation therapy. To minimize imaging artifacts, kilovoltage CT (kVCT) treatment planning was conducted without shielding. Generous hypothetical contours were generated on each 'planning scan' to estimate the location of the lead shield and generate a directionally blocked helical tomotherapy plan. To ensure the accuracy of each plan, megavoltage fan-beam CT (MVCT) scans were obtained at the first treatment and adaptive planning was performed to account for lead shield placement. Two important regions of interest in these cases were femurs and femoral heads. During adaptive planning for the first patient, it was observed that the virtual lead shield contour on kVCT planning images was significantly larger than the actual lead shield used for treatment. However, for the second patient, it was noted that the size of the virtual lead shield contoured on the kVCT image was significantly smaller than the actual shield size. Thus, new adaptive plans based on MVCT images were generated and used for treatment. The planning target volume was underdosed up to 2% and had higher maximum doses without adaptive planning. In conclusion, the treatment of the upper thigh, particularly in young men, presents several clinical challenges, including preservation of gonadal function. In such circumstances, adaptive planning using MVCT can ensure accurate dose delivery even in the presence of high-density testicular shields.

Yadav, Poonam [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); School of Advance Sciences, Vellore Institue of Technology University, Vellore, Tamil Nadu (India); Kozak, Kevin [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Tolakanahalli, Ranjini [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Ramasubramanian, V. [School of Advance Sciences, Vellore Institue of Technology University, Vellore, Tamil Nadu (India); Paliwal, Bhudatt R. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin, Riverview Cancer Centre, Wisconsin Rapids, WI (United States); Welsh, James S. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Rong, Yi, E-mail: rong@humonc.wisc.edu [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin, Riverview Cancer Centre, Wisconsin Rapids, WI (United States)

2012-07-01T23:59:59.000Z

239

Computational and Experimental Validation of a WGPu Neutron Leakage Source Using a Shielded PuBe (,n) Neutron Source  

Science Conference Proceedings (OSTI)

Neutron Measurements / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

Gabriel Ghita; Glenn Sjoden; James Baciak

240

Earth pressure balance (EPB) shield tunneling in Bangkok : ground response and prediction of surface settlements using artificial neural networks  

E-Print Network (OSTI)

Although Earth Pressure Balance (EPB) shields have been used for several decades, very little information exists about the actual mechanisms of shield-ground interaction. The ground response mechanism induced by EPB tunneling ...

Suwansawat, Suchatvee, 1972-

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Atomic Data for Americium (Am)  

Science Conference Proceedings (OSTI)

... Atomic Number = 95. Atomic Weight = (243). Reference E95. Isotope, Mass, Abundance, Spin, Mag Moment, 241 Am, 241.056823, 0, 5/2, +1.61. ...

242

Standard Guide for Dry Lead Glass and Oil-Filled Lead Glass Radiation Shielding Window Components for Remotely Operated Facilities  

E-Print Network (OSTI)

Standard Guide for Dry Lead Glass and Oil-Filled Lead Glass Radiation Shielding Window Components for Remotely Operated Facilities

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

243

Depth Profiles of Radionuclides Induced in Shielding Concrete of the 12 GeV Proton Accelerator Facility at KEK  

E-Print Network (OSTI)

Depth Profiles of Radionuclides Induced in Shielding Concrete of the 12 GeV Proton Accelerator Facility at KEK

Miura, T; Ishihama, S; Ohotsuka, N; Kunifuda, T

2000-01-01T23:59:59.000Z

244

Questions and Answers - How do atoms form?  

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

(Biggest and smallest atom?) Questions and Answers Main Index Next Question (Does gravity affect atoms?) Does gravity affect atoms? How do atoms form? The current view is that...

245

Questions and Answers - Can you crush atoms?  

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

Does gravity affect atoms? Previous Question (Does gravity affect atoms?) Questions and Answers Main Index Next Question (Parts and weights of atoms?) Parts and weights of atoms?...

246

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

247

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

248

Material and electromagnetic properties of Faraday shields for ion cyclotron heating antennas  

Science Conference Proceedings (OSTI)

The Faraday shields for ion cyclotron antennas must transmit magnetic waves and adsorb little rf power. To investigate these properties, we have constructed 27 Faraday shields in many configurations, including chevrons, tubes, straps, concentric rings, various layered shields, conventionally leafed straps, and replicas of the Faraday shields for ASDEX, the Joint European Torus (JET), TEXTOR, and Alcator-C. We have measured the magnetic flux and observed loading at various operating resistances by using dielectric sheets or magnetic-coupled loads. Each Faraday shield effects a net change in the characteristic inductance of the antenna, resulting in a reduction of wave coupling. However, the load experienced by the antenna is not always reduced because the Faraday shield itself acts as a load. We differentiate between these effects experimentally. The net result of the study is that the Faraday shields now in use cost up to a factor of 50% of coupling. This, of course, reduces the power handling capability by 50% as well. However, configurations exist that are easily cooled and result in a reduction of less than 5% in loading.

Hoffman, D.J.; Becraft, W.R.; Baity, F.W.; Caughman, J.B.O.; Tsai, C.C.

1985-01-01T23:59:59.000Z

249

NIST Atomic Spectroscopy Data Center  

Science Conference Proceedings (OSTI)

Atomic Spectroscopy Data Center. ... Responds to user requests for data, literature references, and technical information. ...

2011-11-29T23:59:59.000Z

250

Lesson 3- Atoms and Isotopes  

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

You’ve 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.

251

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.

252

Debye shielding in a dusty plasma with nonextensively distributed electrons and ions  

SciTech Connect

The phenomenon of Debye shielding in dusty plasmas is investigated within the framework of nonextensively distributed electrons and ions. The effects of dust grain charge fluctuation are considered. It shows that the increase of the nonextensive parameters of electrons and ions will lead to the decrease of the shielding distance and it is due to that the effective temperature of nonextensively distributed particles drops with the increase of nonextensive parameters. There is a rather interesting result that the Debye shielding effects may vanish in a certain condition when the fluctuation of the dust grain charges is taken into account.

Liu, Y.; Xu, K. [School of Sciences, Nantong University, Nantong 226019 (China); Liu, S. Q. [School of Sciences, Nanchang University, Nanchang 330047 (China)

2012-07-15T23:59:59.000Z

253

Estimation of radiation doses for atomic-bomb survivors in the Hiroshima University Registry  

Science Conference Proceedings (OSTI)

The present study presents the Hiroshima University Registry of atomic bomb survivors, of which the total number is about 270,000, and application of absorbed doses. From this registry, we picked up 49,102 survivors and applied organ doses based on the dosimetry system 1986 (DS86), which is named the Atomic Bomb Survivor 1993 Dose (ABS93D). The applied dose data are based on the tables listed in the DS86 final report such as the free-in-air kermas, the house shielding factors, and organ dose factors for the active bone marrow and the breast. Calculations for the 13 other organs provided in DS86 are possible. To obtained the organ doses for each survivor, it is necessary to obtain information concerning (1) place exposed, (2) whether they were shielded or not, and (3) age. ABS93D body transmission factors for active bone marrow for neutrons and gamma rays agreed with DS 86 to within a few percent. Of the survivors studied, 35, 123 of them were used for the relative risk estimation of leukemia mortality, adopting the same method as the Radiation Effects Research Foundation (RERF) for comparison. For the observation period from 1968 to 1989, the analyzed relative risks for leukemia mortality at 1 Gy by shielded kerm and by active bone marrow dose are 2.01 and 2.37, respectively, which are consistent with the RERF results. 11 refs., 1 fig., 3 tabs.

Hoshi, M.; Matsuura, M.; Hayakawa, N.; Kamada, N. [Hiroshima Univ., Kasumi (Japan); Ito, C. [Hiroshima A-bomb Casualty Council Health Management Promotion Center, Senda-machi Naka-ku (Japan)

1996-05-01T23:59:59.000Z

254

Report of the AGS Experimental Area Shielding Upgrade Committee  

SciTech Connect

The proton intensity delivered to the AGS experimental areas is expected to increase fourfold when the full potential of the Booster is realized. It is therefore necessary to anticipate the modifications to the shielding and radiation monitoring that will be required in order to insure safe operation within the appropriate guidelines for radiation exposure. This report examines the consequences of site boundary requirements and soil and air activation as well as the protection of radiation workers, i.e., AGS personnel and experimenters, from unnecessary radiation exposure in the experimental areas. Where possible, Health Physics surveys and fault studies carried out in the Spring of 1990 have been used to estimate levels in and around the experimental areas with 5 {times} 10{sup 13} protons per pulse or 75% of the total anticipated intensity delivered to each of the target stations under normal'' as well as fault conditions. Where fault studies were not possible due to construction, the new beams and facilities were designed for the higher intensities that will be available and radiation patterns were calculated. Weak spots were identified and improvements recommended. Capital and manpower estimates were developed for the upgrades. 7 refs.

Beavis, D.; Brown, H.N.; Bunce, G.; Carroll, A.S.; Chiang, I.H.; Glenn, J.W.; Lazarus, D.M.; Lessard, E.; Pendzick, A.; Sims, W.; Woodle, K.

1990-08-01T23:59:59.000Z

255

General Corrosion and Localized Corrosion of the Drip Shield  

SciTech Connect

The recommended waste package (WP) design is described in BSC (2001a). The design includes a double-wall WP underneath a protective drip shield (DS) (BSC 2003a). The purpose of the process-level models developed in this report is to model dry oxidation (DOX), general corrosion (GC) and localized corrosion (LC) of the DS plate material, which is made of Ti Grade 7. The DS design also includes structural supports fabricated from Ti Grade 24. Degradation of Ti Grade 24 is not considered in this report. The DS provides protection for the waste package outer barrier (WPOB) both as a barrier to seepage water contact and a physical barrier to potential rockfall. This Model Report (MR) serves as a feed to the Integrated Waste Package Degradation Model (IWPD) analyses, and was developed in accordance with the Technical Work Plan (TWP) (BSC 2002a). The models contained in this report serve as a basis to determine whether or not the performance requirements for the DS can be met.

F. Hua; K. Mon

2003-06-24T23:59:59.000Z

256

Increasing transcurium production efficiency through direct resonance shielding  

Science Conference Proceedings (OSTI)

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

257

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

258

JILA Researchers Discover Atomic Clock Can Simulate ...  

Science Conference Proceedings (OSTI)

... Artist's conception of interactions among atoms in JILA's strontium atomic clock during a quantum simulation experiment. ...

2013-08-20T23:59:59.000Z

259

ATOMIC BATTERY AND TEST INSTRUMENT  

SciTech Connect

A portable nuclear battery is designed which can be adjusted to vary the output. The battery comprises a Sr/sup 90/ peactivated phosphor light source and photocells housed in a shielding structure. The output may be varied by rotating elements between the light source and the photocells. (D.L.C.)

Viszlocky, N.

1962-09-11T23:59:59.000Z

260

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

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

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

262

Pollution prevention benefits of non-hazardous shielding glovebox gloves - 11000  

SciTech Connect

Radiation shielding is commonly used to protect the glovebox worker from unintentional direct and secondary radiation exposure, while working with plutonium-238 and plutonium-239. Shielding glovebox gloves are traditionally composed of lead-based materials, i.e., hazardous waste. This has prompted the development of new, non-hazardous shielding glovebox gloves. No studies, however, have investigated the pollution prevention benefits of these new glovebox gloves. We examined both leaded and non-hazardous shielding glovebox gloves. The nonhazardous substitutes are higher in cost, but this is offset by eliminating the costs associated with onsite waste handling of Resource Conservation and Recovery Act (RCRA) items. In the end, replacing lead with non-hazardous substitutes eliminates waste generation and future liability.

Cournoyer, Michael E [Los Alamos National Laboratory; Dodge, Robert L [Los Alamos National Laboratory

2011-01-11T23:59:59.000Z

263

Effects of Radar Beam Shielding on Rainfall Estimation for the Polarimetric C-Band Radar  

Science Conference Proceedings (OSTI)

Radar reflectivity (Zh), differential reflectivity (Zdr), and specific differential phase (Kdp) measured from the operational, polarimetric weather radar located in Trappes, France, were used to examine the effects of radar beam shielding on ...

Katja Friedrich; Urs Germann; Jonathan J. Gourley; Pierre Tabary

2007-11-01T23:59:59.000Z

264

Some Perspectives on Recent In Situ Air Temperature Observations: Modeling the Microclimate inside the Radiation Shields  

Science Conference Proceedings (OSTI)

Air temperature measurement has inherent biases associated with the particular radiation shield and sensor deployed. The replacement of the Cotton Region Shelter (CRS) with the Maximum–Minimum Temperature System (MMTS) and the introduction of ...

X. Lin; K. G. Hubbard; E. A. Walter-Shea; J. R. Brandle; G. E. Meyer

2001-09-01T23:59:59.000Z

265

Recommendations for a Static Cosmic Ray Shield for Enriched Germanium Detectors  

SciTech Connect

This document provides a detailed study of cost and materials that could be used to shield the detector material of the international Tonne-scale germanium neutrinoless double-beta decay experiment from hadronic particles from cosmic ray showers at the Earth's surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during storage; in particular, when the detector material is being worked on at the detector manufacturer's facility. This work considers two options for shielding the detector material from cosmic ray particles. One option is to use a pre-existing structure already located near the detector manufacturer, such as Canberra Industries in Meriden, Connecticut. The other option is to build a shield onsite at a detector manufacturer's site. This paper presents a cost and efficiency analysis of such construction.

Aguayo Navarrete, Estanislao; Orrell, John L.; Ankney, Austin S.; Berguson, Timothy J.

2011-09-21T23:59:59.000Z

266

HZETRN: Description of a Free-Space Ion and Nucleon Transport and Shielding Computer Program  

Science Conference Proceedings (OSTI)

The high-charge-and-energy (HZE) transport computer program HZETRN is developed to address the problems of free-space radiation transport and shielding. The HZETRN program is intended specifically for the design engineer who is interested in obtaining ...

Wilson John W.; Badavi Francis F.; Cucinotta Francis A.; Shinn Judy L.; Badhwar Gautam D.; Silberberg R.; Tsao C. H.; Townsend Lawrence W.; Tripathi Ram K.

1995-05-01T23:59:59.000Z

267

An Effective, Economic, Aspirated Radiation Shield for Air Temperature Observations and Its Spatial Gradients  

Science Conference Proceedings (OSTI)

This paper presents the design and evaluates the performance of a double-walled electrically aspirated radiation shield for thermometers measuring air temperature and its gradients in the atmospheric surface layer. Tests were performed to quantify ...

Christoph K. Thomas; Alexander R. Smoot

2013-03-01T23:59:59.000Z

268

Assessment of Dancoff adjusted Wigner-Seitz cells for self-shielding LWR lattices  

E-Print Network (OSTI)

The objective of this thesis was to assess the effectiveness of using a Wigner-Seitz (WS) cell with an adjusted moderator thickness to produce more accurate resonance self-shielded cross sections for light water reactor ...

Roomy, Thomas Hayward

2012-01-01T23:59:59.000Z

269

The Energy Budget of Canadian Shield Subarctic Terrain and Its Impact on Hillslope Hydrological Processes  

Science Conference Proceedings (OSTI)

The objective of the study is to determine the local processes that control the partitioning of the energy budget of shield terrain in the western Canadian subarctic. The magnitude of the spring snowmelt and its potential to flood exposed bedrock ...

Christopher Spence; Wayne R. Rouse

2002-04-01T23:59:59.000Z

270

Graphit-ceramic RF Faraday-thermal shield and plasma limiter  

DOE Patents (OSTI)

The present invention is directed to a process of brazing a ceramic mater to graphite. In particular, the brazing procedure is directed to the production of a novel brazed ceramic graphite product useful as a Faraday shield.

Hwang, David L. (Princeton Junction, NJ); Hosea, Joel C. (Princeton, NJ)

1989-01-01T23:59:59.000Z

271

Electromagnetic analysis of forces and torques on the ITER shield modules due to plasma disruption.  

SciTech Connect

An electromagnetic analysis is performed on the ITER shield modules under different plasma disruption scenarios using the OPERA-3d software. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

2009-06-01T23:59:59.000Z

272

Molecular based magnets comprising vanadium tetracyanoethylene complexes for shielding electromagnetic fields  

DOE Patents (OSTI)

The invention presents a vanadium tetracyanoethylene solvent complex for electromagnetic field shielding, and a method for blocking low frequency and magnetic fields using these vanadium tetracyanoethylene compositions. The compositions of the invention can be produced at ambient temperature and are light weight, low density and flexible. The materials of the present invention are useful as magnetic shields to block low frequency fields and static fields, and for use in cores in transformers and motors.

Epstein, Arthur J. (Columbus, OH); Morin, Brian G. (Columbus, OH)

1998-01-01T23:59:59.000Z

273

Evaluation of an Advanced Radiation Shielding Material for Permanent Installation at an Operating Commercial Nuclear Reactor  

Science Conference Proceedings (OSTI)

The industry continues to investigate, validate, and implement new radiation field reduction measures in response to increased emphasis on reducing dose to workers. Many nuclear plants are interested in permanent shielding applications to further reduce personnel exposure and to reduce the recurring effort associated with temporary installations. In 2008, a flexible, impregnated, layered matrix material was identified as a possible material for incorporating a shielding substance. This report provides an...

2010-09-30T23:59:59.000Z

274

Molecular based magnets comprising vanadium tetracyanoethylene complexes for shielding electromagnetic fields  

DOE Patents (OSTI)

The invention presents a vanadium tetracyanoethylene solvent complex for electromagnetic field shielding, and a method for blocking low frequency and magnetic fields using these vanadium tetracyanoethylene compositions. The compositions of the invention can be produced at ambient temperature and are light weight, low density and flexible. The materials of the present invention are useful as magnetic shields to block low frequency fields and static fields, and for use in cores in transformers and motors. 21 figs.

Epstein, A.J.; Morin, B.G.

1998-10-13T23:59:59.000Z

275

THE EFFECT OF A MINIMUM WEIGHT RADIAL REFLECTOR ON SNAP SHIELDING REQUIREMENTS  

SciTech Connect

A model was derived for a minimum-weight radial reflector for SNAP reactors. The effect, which the use of this optimal reflector has on radiation shield weight requirements is investigated. Weights of systems employing conventional and optimal radial reflectors are compared using the FARSE and FARSER computer codes. It is found that for the configuration under study additional shield weight required when the optimal reflector is used is in excess of the reflector weight savings. (auth)

Bernick, R.L.

1963-10-17T23:59:59.000Z

276

Radiation Shielding Analysis for Direct Use of Spent Pressurized Water Reactor Fuel in CANDU Reactors (DUPIC)  

Science Conference Proceedings (OSTI)

As a part of the compatibility analysis of DUPIC fuel in Canada deuterium uranium (CANDU) reactors, the radiation physics calculations have been performed for the CANDU primary shielding system, which was originally designed for natural uranium core. At first, the conventional CANDU primary shield analysis method was validated using the Monte Carlo code MCNP-4B in order to assess the current analysis code system and the cross-section data. The computational benchmark calculation was performed for the CANDU end shield system, which has shown that the conventional method produces results consistent with the reference calculations as far as the total dose rate and total heat deposition rate are concerned. Second, the primary shield system analysis was performed for the DUPIC fuel core based on the power distribution obtained from the time-average core model, and the results have shown that the dose rates and heat deposition rates through the primary shield of the DUPIC fuel core are not much different from those of the natural uranium core because the power levels on the core periphery are similar for both cores. This study has shown that the current primary shield system is adaptable for the DUPIC fuel CANDU core without design modification.

Roh, Gyuhong; Choi, Hangbok [Korea Atomic Energy Research Institute (Korea, Republic of)

2004-06-15T23:59:59.000Z

277

Advanced shield development for a fission surface power system for the lunar surface  

SciTech Connect

A nuclear reactor power system such as the affordable fission surface power system enables a potential outpostonthemoon.Aradiation shieldmustbe included in the reactor system to reduce the otherwise excessive dose to the astronauts and other vital system components. The radiation shield is typically the most massive component of a space reactor system, and thus must be optimized to reduce mass asmuchas possible while still providing the required protection.Various shield options for an on-lander reactor system are examined for outpost distances of 400m and 1 kmfromthe reactor. Also investigated is the resulting mass savings from the use of a high performance cermet fuel. A thermal analysis is performed to determine the thermal behaviours of radiation shields using borated water. For an outpost located 1000m from the core, a tetramethylammonium borohydride shield is the lightest (5148.4 kg), followed by a trilayer shield (boron carbide–tungsten–borated water; 5832.3 kg), and finally a borated water shield (6020.7 kg). In all of the final design cases, the temperature of the borated water remains below 400 K.

A. E. Craft; I. J. Silver; C. M. Clark; S. D. Howe; J. C. King

2011-02-01T23:59:59.000Z

278

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

279

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

280

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

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

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

Science Conference Proceedings (OSTI)

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

2013-01-01T23:59:59.000Z

282

Tenth Atomic Physics Program workshop  

Science Conference Proceedings (OSTI)

This report contains short papers and abstracts on the following main topics: Ion-atom collision theory; laser physics; spectroscopy of atoms; spectroscopy of ions; and high velocity collisions.

Not Available

1989-10-01T23:59:59.000Z

283

Nuclear effects in atomic transitions  

E-Print Network (OSTI)

Atomic electrons are sensitive to the properties of the nucleus they are bound to, such as nuclear mass, charge distribution, spin, magnetization distribution, or even excited level scheme. These nuclear parameters are reflected in the atomic transition energies. A very precise determination of atomic spectra may thus reveal information about the nucleus, otherwise hardly accessible via nuclear physics experiments. This work reviews theoretical and experimental aspects of the nuclear effects that can be identified in atomic structure data. An introduction to the theory of isotope shifts and hyperfine splitting of atomic spectra is given, together with an overview of the typical experimental techniques used in high-precision atomic spectroscopy. More exotic effects at the borderline between atomic and nuclear physics, such as parity violation in atomic transitions due to the weak interaction, or nuclear polarization and nuclear excitation by electron capture, are also addressed.

Pálffy, Adriana

2011-01-01T23:59:59.000Z

284

Atomic Devices and Instrumentation Group  

Science Conference Proceedings (OSTI)

... 2001 and 2005, demonstrated an atomic clock physics package with ... magnetometers for magnetic anomaly detection, nuclear magnetic resonance ...

2013-08-09T23:59:59.000Z

285

Atom-Based Dimensional Metrology  

Science Conference Proceedings (OSTI)

... Awarded a five year, three phase DARPA contract to conduct collaborative research in atomically precise positioning, patterning and metrology ...

2013-04-19T23:59:59.000Z

286

Structural Calculations of Drip Shield Exposed to Vibratory Ground Motion  

Science Conference Proceedings (OSTI)

The objective of this calculation is twofold. First, to determine whether or not separation of interlocking drip shield (DS) segments occurs during vibratory ground motion. Second, if DS separation does not occur, to estimate the area of the DS for which the residual 1st principal stress exceeds a certain limit. (The area of DS plate-1 and DS plate-2 [see Attachment I] where the residual 1st principal stress exceeds a certain limit will be, for brevity, referred to as ''the damaged area'' throughout this document; also, DS plate-1 and DS plate-2 will be referred to, for brevity, as ''DS plates'' henceforth.) The stress limit used throughout this document is defined as 50 percent of yield strength of the DS plate material, Titanium Grade 7 (Ti-7) (SB-265 R52400), at temperature of 150 C. A set of 15 calculations is performed at two different annual frequencies of occurrence (annual exceedance frequency): 10{sup -6} per year (1/yr) and 10{sup -7} 1/yr . (Note: Due to computational problems only five realizations at 10{sup -7} 1/yr are presented in this document.) Additionally, one calculation is performed at the annual frequency of occurrence of 5 {center_dot} 10{sup -4} 1/yr. The scope of this document is limited to reporting whether or not the DS separation occurs. If the DS separation does not occur the scope is limited to reporting the calculation results in terms of the damaged area. All these results are evaluated for the DS plates. This calculation is intended for use in support of the Total System Performance Assessment-License Application seismicity modeling. This calculation is associated with the DS design and was performed by the Waste Package Design group. AP-3.12Q, ''Design Calculations and Analyses'' (Ref. 1) is used to perform the calculation and develop the document. The DS is classified as Quality Level 1 (Ref. 5, p. 7). Therefore, this calculation is subject to the Quality Assurance Requirements and Description (Ref. 4). The information provided by Attachment I is that of the potential design of the type of DS considered in this calculation, and provides the potential dimensions and materials for the DS design. Designs of the 21-PWR (Pressurized Water Reactor) waste package (WP) and emplacement pallet (pallet, for brevity, throughout the document) used in this calculation are those defined in References 24 and 22, respectively. All obtained results are valid for these designs only.

S. Mastilovic

2003-06-16T23:59:59.000Z

287

Why is hydrogen's atomic number 1?  

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

the number of protons in an atom's nucleus. Hydrogen's atomic number is 1 because all hydrogen atoms contain exactly one proton. Author: Steve Gagnon, Science Education Specialist...

288

NIST: Phys. Lab. Brochure; Atomic Physics Div.  

Science Conference Proceedings (OSTI)

... ultra-cold atoms and investigate atom optics for innovative instrumentation. Measure and analyze spectra of highly ionized atoms for fusion energy ...

289

Atomic data for fusion  

DOE Green Energy (OSTI)

This report provides a handbook of recommended cross-section and rate-coefficient data for inelastic collisions between hydrogen, helium and lithium atoms, molecules and ions, and encompasses more than 400 different reactions of primary interest in fusion research. Published experimental and theoretical data have been collected and evaluated, and the recommended data are presented in tabular, graphical and parametrized form. Processes include excitation and spectral line emission, charge exchange, ionization, stripping, dissociation and particle interchange reactions. The range of collision energies is appropriate to applications in fusion-energy research.

Hunter, H.T.; Kirkpatrick, M.I.; Alvarez, I.; Cisneros, C.; Phaneuf, R.A. (eds.) [eds.; Barnett, C.F.

1990-07-01T23:59:59.000Z

290

Material Shielding of Power Frequency Magnetic Fields: Research and Testing Results from the EPRI Power Delivery Center -- Lenox  

Science Conference Proceedings (OSTI)

Magnetic fields from power lines and other electrical facilities can interfere with sensitive electronic equipment such as computers, electron microscopes, medical diagnostic and monitoring equipment, and air traffic control displays. Shields can be designed to reduce the magnetic field strength in the areas of interest, but attention must be given to certain aspects of shield design. This report deals with three aspects of practical shield construction: flat sheet dimensions, joining sheets, and thin co...

1998-06-29T23:59:59.000Z

291

An Evaluation of Shadow Shielding for Lunar System Waste Heat Rejection  

E-Print Network (OSTI)

Shadow shielding is a novel and practical concept for waste heat rejection from lunar surface spacecraft systems. A shadow shield is a light shield that shades the radiator from parasitic thermal radiation emanating from the sun or lunar surface. Radiator size and mass can reduce if the radiator is not required to account for parasitic heat loads in addition to system energy rejection requirements. The lunar thermal environment can be very harsh towards radiative heat rejection. Parasitic heat loads force the radiator to expand in size and mass to compensate. On the Moon, there are three types: surface infrared, solar insulation, and albedo. This thesis tests shadow shielding geometry and its effect on the radiator and nuclear reactor in a reactor-powered Carnot heat engine. Due to the nature of cooling by radiative heat transfer, the maximum shaft work a Carnot system can produce and the minimal required radiator area occurs when the Carnot efficiency is 25%. First, a case for shadow shielding is made using an isothermal, control radiator model in Thermal Desktop. Six radiator temperatures and three latitudes are considered in the tests. Test variables in this section include radiator shapes and shade geometry. The simulations found that shadow shielding is best suited for a low-temperature radiator at the lunar equator. Optimized parabolic shade geometry includes a focus right above or at the top of the radiator and full to three-quarters shade height. The most useful rectangular radiator shape for shadow shielding is that which has a low height and long width. All simulations were conducted using a shade with a 10 kg/m2 area mass. A sensitivity study was conducted for different shade area masses using high and low values found in the literature. The shade is the most useful when the shade's area mass is less than or equal to that of the radiator. If the shade mass is below this threshold, the shade would be applicable to all radiator temperatures tested. Optimized shade and radiator geometry results were then factored into a second model where the radiator is comprised of heat pipes which is similar to radiators from actual system designs. Further simulations were conducted implementing the SAFE-4001 fast fission nuclear reactor design. The study found that shadow shielding allowed the system to use a low-temperature radiator where other configurations were not viable because shadow shielding drastically improves radiative heat transfer from the radiator, but at the consequence of raising radiator mass.

Worn, Cheyn

2012-05-01T23:59:59.000Z

292

Cancer in atomic bomb survivors  

SciTech Connect

This book presents information on the following topics: sampling of atomic bomb survivors and method of cancer detection in Hiroshima and Nagasaki; atomic bomb dosimetry for epidemiological studies of survivors in Hiroshima and Nagasaki; tumor and tissue registries in Hiroshima and Nagasaki; the cancer registry in Nagasaki, with atomic bomb survivor data, 1973-1977; cancer mortality; methods for study of delayed health effects of a-bomb radiation; experimental radiation carcinogenesis in rodents; leukemia, multiple myeloma, and malignant lymphoma; cancer of the thyroid and salivary glands; malignant tumors in atomic bomb survivors with special reference to the pathology of stomach and lung cancer; colorectal cancer among atomic bomb survivors; breast cancer in atomic bomb survivors; and ovarian neoplasms in atomic bomb survirors.

Shigematsu, I.; Kagan, A.

1986-01-01T23:59:59.000Z

293

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

294

Development of a Coating Formulation Procedure for Ni-base Shielded Metal Arc Electrodes with Varying Core Wire Composition.  

E-Print Network (OSTI)

??In order for manufacturers of shielded metal arc welding (SMAW) electrodes to stay competitive, they must be able to have flexibility in the performance of… (more)

Gaal, Brian

2012-01-01T23:59:59.000Z

295

The Study of Electromagnetic Shielding Employing Woven Continuous Carbon Fiber Composites for 2.5Gb/s Transceiver Modules.  

E-Print Network (OSTI)

??A High electromagnetic shielding, light weight, low cost plastic package is developed by using a woven continuous carbon fiber (WCCF) epoxy composite. Three different weaving… (more)

Lee, Chien-hui

2004-01-01T23:59:59.000Z

296

Questions and Answers - Does gravity affect atoms?  

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

and Answers Main Index Next Question (Can you crush atoms?) Can you crush atoms? Does gravity affect atoms? Gravity affects atoms the same way it affects all other matter. Every...

297

Optics and interferometry with atoms and molecules  

E-Print Network (OSTI)

Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic ...

Cronin, Alexander D.

298

Magnetometry with entangled atomic samples  

E-Print Network (OSTI)

We present a theory for the estimation of a scalar or a vector magnetic field by its influence on an ensemble of trapped spin polarized atoms. The atoms interact off-resonantly with a continuous laser field, and the measurement of the polarization rotation of the probe light, induced by the dispersive atom-light coupling, leads to spin-squeezing of the atomic sample which enables an estimate of the magnetic field which is more precise than that expected from standard counting statistics. For polarized light and polarized atoms, a description of the non-classical components of the collective spin angular momentum for the atoms and the collective Stokes vectors of the light-field in terms of effective gaussian position and momentum variables is practically exact. The gaussian formalism describes the dynamics of the system very effectively and accounts explicitly for the back-action on the atoms due to measurement and for the estimate of the magnetic field. Multi-component magnetic fields are estimated by the measurement of suitably chosen atomic observables and precision and efficiency is gained by dividing the atomic gas in two or more samples which are entangled by the dispersive atom-light interaction.

Vivi Petersen; Lars Bojer Madsen; Klaus Molmer

2004-09-28T23:59:59.000Z

299

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

300

Numerical simulation of high-speed penetration-perforation dynamics in layered armor shields  

E-Print Network (OSTI)

Penetration models and calculating algorithms are presented, describing the dynamics and fracture of composite armor shields penetrated by high-speed small arms. A shield considered consists of hard (metal or ceramic) facing and multilayered fabric backing. A simple formula is proved for the projectile residual velocity after perforation of a thin facing. A new plastic-flow jet model is proposed for calculating penetration dynamics in the case of a thick facing of ceramic or metal-ceramic FGM materials. By bringing together the developed models into a calculating algorithm, a computer tool is designed enabling simulations of penetration processes in the above-mentioned shields and analysis of optimization problems. Some results of computer simulation are presented. It is revealed in particular that strength proof of pliable backing can be better as compared with more rigid backing. Comparison of calculations and test data shows sufficient applicability of the models and the tool.

Ayzenberg-Stepanenko, Mark

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Numerical simulation of high-speed penetration-perforation dynamics in layered armor shields  

E-Print Network (OSTI)

Penetration models and calculating algorithms are presented, describing the dynamics and fracture of composite armor shields penetrated by high-speed small arms. A shield considered consists of hard (metal or ceramic) facing and multilayered fabric backing. A simple formula is proved for the projectile residual velocity after perforation of a thin facing. A new plastic-flow jet model is proposed for calculating penetration dynamics in the case of a thick facing of ceramic or metal-ceramic FGM materials. By bringing together the developed models into a calculating algorithm, a computer tool is designed enabling simulations of penetration processes in the above-mentioned shields and analysis of optimization problems. Some results of computer simulation are presented. It is revealed in particular that strength proof of pliable backing can be better as compared with more rigid backing. Comparison of calculations and test data shows sufficient applicability of the models and the tool.

Mark Ayzenberg-Stepanenko; Grigory Osharovich

2012-03-07T23:59:59.000Z

302

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.

303

Orthogonally interdigitated shielded serpentine travelling wave cathod ray tube deflection structure  

DOE Patents (OSTI)

This invention comprises a new deflection structure which deflects a beam of charged particles, such as an electron beam, includes a serpentine set for transmitting a deflection field, and shielding frame for housing the serpentine set. The serpentine set includes a vertical serpentine deflection element and a horizontal serpentine deflection element. These deflection elements are identical and are interdigitatedly and orthogonally disposed relative to each other, for forming a central transmission passage, through which the electron beam passes and is deflected by the deflection field to minimize drift space signal distortion. The shielding frame includes a plurality of ground blocks and forms an internal serpentine trough within these ground blocks for housing the serpentine set. The deflection structure further includes a plurality of feedthrough connectors which are inserted through the shielding frame and which are electrically connected to the serpentine set.

Hagen, E.C.; Hudson, C.L.

1993-10-27T23:59:59.000Z

304

Shielding Calculations for the Hard X-Rays Generated by LCLS Mec Laser System  

Science Conference Proceedings (OSTI)

Linac Coherent Light Source (LCLS) Matter in Extreme Conditions (MEC) Instrument is an X-ray instrument that will be able to create and diagnose High Energy Density (HED) matter. The MEC laser system can generate hard X-ray due to the interaction of the laser and the plasma. This paper summarizes results of the shielding calculations performed to evaluate the radiation hazards induced by this hard X-ray source with Monte Carlo code FLUKA. The dose rates and photon spectra due to this X-ray source are calculated at different locations with different shielding. The influence of the electron temperature on the source terms and the shielding effectiveness was also investigated.

Not Available

2011-06-02T23:59:59.000Z

305

Options for Shielding Tokamak Cooling Water Electrical Components against High Magnetic Fields  

SciTech Connect

The Tokamak Cooling Water System (TCWS) Instrumentation and Control (I&C) components of ITER will be located in areas of relatively high magnetic fields. Previous tests on electrical and I&C components have indicated that shielding will be required to protect these components from such magnetic fields. To accomplish this, studies were performed by AREVA Federal Services (AFS) in support of the TCWS Design project with the intent of identifying an optimal solution for shielding I&C components. This report presents a summary of these studies and presents design options for providing magnetic shielding to ITER TCWS I&C components and electrical equipment that are susceptible to the magnetic fields present.

Korsah, Kofi [ORNL; Michael, Smith [AREVA Federal Services LLC; Kim, Seokho H [ORNL; Charles, Neumeyer [Princeton Plasma Physics Laboratory (PPPL)

2011-01-01T23:59:59.000Z

306

Contoured inner after-heater shield for reducing stress in growing crystalline bodies  

DOE Patents (OSTI)

An apparatus for growing hollow crystalline bodies by the EFG process, comprising an EFG die having a top surface shaped for growing a hollow crystalline body having a cross-sectional configuration in the shape of a polygon having n faces, and a radiation shield adjacent to and surrounded by the top end surface of the die, characterized in that the shield has an inner edge defining a similar polygon with n sides, and the inner edge of the shield is notched so that the spacing between the n faces and the n sides is greatest between the central portions of the n faces and the n sides, whereby the greater spacing at the central portions helps to reduce lateral temperature gradients in the crystalline body that is grown by use of the die.

Kalejs, Juris P. (Wellesley, MA)

1996-09-24T23:59:59.000Z

307

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 Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear...

308

Atomic total energies: Atomic Ref.Data Elec Struc Cal  

Science Conference Proceedings (OSTI)

... These tables contain the atomic total energies and orbital eigenvalues, for the ground electronic configuration of the elements H ... Definition of format ...

309

Atomic total energies: Atomic Ref. Data Elec. Struc. Cal.  

Science Conference Proceedings (OSTI)

... These tables contain the atomic total energies and orbital eigenvalues, for the ground electronic configuration of the elements H ... Definition of format ...

310

Laser Cooling and Cold Atomic Matter  

Science Conference Proceedings (OSTI)

Laser Cooling and Cold Atomic Matter: to advance the understanding and applications of cold atomic matter, including ...

2012-05-30T23:59:59.000Z

311

NIST - Atomic Energy Levels and Spectra Bibliographic ...  

Science Conference Proceedings (OSTI)

... in this database are from Bibliography on Atomic Energy Levels and ... references to atomic transition probabilities, line intensities, or broadening. ...

312

A User's Manual for MASH V1.5 - A Monte Carlo Adjoint Shielding Code System  

Science Conference Proceedings (OSTI)

The Monte Carlo ~djoint ~ielding Code System, MASH, calculates neutron and gamma- ray environments and radiation protection factors for armored military vehicles, structures, trenches, and other shielding configurations by coupling a forward discrete ordinates air- over-ground transport calculation with an adjoint Monte Carlo treatment of the shielding geometry. Efficiency and optimum use of computer time are emphasized. The code system includes the GRTUNCL and DORT codes for air-over-ground transport calculations, the MORSE code with the GIFT5 combinatorial geometry package for adjoint shielding calculations, and several peripheral codes that perform the required data preparations, transformations, and coupling functions. The current version, MASH v 1.5, is the successor to the original MASH v 1.0 code system initially developed at Oak Ridge National Laboratory (ORNL). The discrete ordinates calculation determines the fluence on a coupling surface surrounding the shielding geometry due to an external neutron/gamma-ray source. The Monte Carlo calculation determines the effectiveness of the fluence at that surface in causing a response in a detector within the shielding geometry, i.e., the "dose importance" of the coupling surface fluence. A coupling code folds the fluence together with the dose importance, giving the desired dose response. The coupling code can determine the dose response as a function of the shielding geometry orientation relative to the source, distance from the source, and energy response of the detector. This user's manual includes a short description of each code, the input required to execute the code along with some helpful input data notes, and a representative sample problem.

C. O. Slater; J. M. Barnes; J. O. Johnson; J.D. Drischler

1998-10-01T23:59:59.000Z

313

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

314

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

Science Conference Proceedings (OSTI)

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

315

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

316

Optimization of the Transport Shield for Neutrinoless Double Beta-decay Enriched Germanium  

SciTech Connect

This document presents results of an investigation of the material and geometry choice for the transport shield of germanium, the active detector material used in 76Ge neutrinoless double beta decay searches. The objective of this work is to select the optimal material and geometry to minimize cosmogenic production of radioactive isotopes in the germanium material. The design of such a shield is based on the calculation of the cosmogenic production rate of isotopes that are known to cause interfering backgrounds in 76Ge neutrinoless double beta decay searches.

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Reid, Douglas J.; Fast, James E.

2012-04-15T23:59:59.000Z

317

Radiation shielding calculations for MuCool test area at Fermilab  

DOE Green Energy (OSTI)

The MuCool Test Area (MTA) is an intense primary beam facility derived directly from the Fermilab Linac to test heat deposition and other technical concerns associated with the liquid hydrogen targets being developed for cooling intense muon beams. In this shielding study the results of Monte Carlo radiation shielding calculations performed using the MARS14 code for the MuCool Test Area and including the downstream portion of the target hall and berm around it, access pit, service building, and parking lot are presented and discussed within the context of the proposed MTA experimental configuration.

Igor Rakhno; Carol Johnstone

2004-05-26T23:59:59.000Z

318

Apparatus for characterizing conductivity of materials by measuring the effect of induced shielding currents therein  

DOE Patents (OSTI)

Apparatus and method for noncontact, radio-frequency shielding current characterization of materials is disclosed. Self- or mutual inductance changes in one or more inductive elements, respectively, occur when materials capable of supporting shielding currents are placed in proximity thereto, or undergo change in resistivity while in place. Such changes can be observed by incorporating the inductor(s) in a resonant circuit and determining the frequency of oscillation or by measuring the voltage induced on a coupled inductive element. The present invention is useful for determining the critical temperature and superconducting transition width for superconducting samples. 10 figures.

Doss, J.D.

1991-05-14T23:59:59.000Z

319

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

Science Conference Proceedings (OSTI)

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

320

NIST Atomic Spectra Bibliographic Databases  

Science Conference Proceedings (OSTI)

... The Atomic Energy Levels Data Center and Data Center on ... Reference Data Program (SRDP) and by NIST's Systems Integration for Manufacturing ...

2010-10-05T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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.


321

Atomic Devices and Instrumentation Group  

Science Conference Proceedings (OSTI)

... ten millionths of a second over the course of one day, and are paving the way for atomic-level timekeeping in portable, battery-operated systems ...

322

NIST: Atomic Spectroscopy Group - Homepage  

Science Conference Proceedings (OSTI)

... The program in atomic spectroscopy at NIST provides accurate reference data on spectral lines and energy levels for a wide variety of important ...

2013-07-31T23:59:59.000Z

323

Technical Highlights Atomic Physics Division  

Science Conference Proceedings (OSTI)

... Physics Division is to develop and apply atomic physics research methods ... community, and to produce and critically compile physical reference data ...

2013-06-04T23:59:59.000Z

324

The Atomic to Molecular Transition in Galaxies. I: An Analytic Approximation for Photodissociation Fronts in Finite Clouds  

E-Print Network (OSTI)

In this series of papers we study the structure of the atomic to molecular transition in the giant atomic-molecular complexes that are the repositories of most molecular gas in galaxies, with the ultimate goal of attaining a better understanding of what determines galaxies' molecular content. Here we derive an approximate analytic solution for the structure of a photodissociation region (PDR) in a cloud of finite size that is bathed in an external dissociating radiation field. Our solution extends previous work, which with few exceptions has been restricted to a one-dimensional treatment of the radiation field. We show that our analytic results compare favorably to exact numerical calculations in the one-dimensional limit. However, our more general geometry provides a more realistic representation than a semi-infinite slab for atomic-molecular complexes exposed to the interstellar radiation field, particularly in environments such as low-metallicity dwarf galaxies where the curvature and finite size of the atomic envelope cannot be neglected. For clouds that are at least 20% molecular we obtain analytic expressions for the molecular fraction in terms of properties of the gas and radiation field that are accurate to tens of percent, while for clouds of lower molecular content we obtain upper limits. As a side benefit, our analysis helps clarify when self-shielding is the dominant process in H_2 formation, and under what circumstances shielding by dust makes a significant contribution.

Mark R. Krumholz; Christopher F. McKee; Jason Tumlinson

2008-05-19T23:59:59.000Z

325

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

326

U.S ITER : electromagnetic analysis of transient forces due to disrupted plasma currents on the ITER shield modules.  

SciTech Connect

This paper describes the electromagnetic analysis that has been completed using the OPERA-3d product to characterize the forces on the ITER shield modules as part of the conceptual design. These forces exist due to the interaction of the eddy currents induced in the shield modules and the large magnetic fields present in the tokamak.

Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis

2007-06-01T23:59:59.000Z

327

Shielding and Activation Analyses in Support of the Spallation Neutron Source (SNS) ES{ampersand}H Requirements  

Science Conference Proceedings (OSTI)

Shielding and activation analyses play an important part in determining how to meet the Environmental, Safety and Health (ES{ampersand}H) requirements of an intense high-energy accelerator facility like the proposed Spallation Neutron Source (SNS). The shielding and activation analyses described in this paper were performed primarily using the CALOR code system coupled with MCNP for radiation transport, the ORIHET95 isotope generation and depletion code for activation analysis, and the DOORS multi-dimensional discrete ordinates transport code system for shielding analyses. Additionally, a portion of the shielding calculations were performed with the semi-empirical code - CASL. This paper gives an overview of relevant ES{ampersand}H policies and requirements, and provides detailed discussions of the shielding and activation analyses completed in support of those policies and requirements.

Odano, Naoteru; Johnson, Jeffrey O.; Harrington, R. M.; DeVore, Joe R.

1998-06-01T23:59:59.000Z

328

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.

329

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

330

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.

331

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.

332

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.

333

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.

334

Continuous Energy, Multi-Dimensional Transport Calculations for Problem Dependent Resonance Self-Shielding  

SciTech Connect

The overall objective of the work here has been to eliminate the approximations used in current resonance treatments by developing continuous energy multi-dimensional transport calculations for problem dependent self-shielding calculations. The work here builds on the existing resonance treatment capabilities in the ORNL SCALE code system.

T. Downar

2009-03-31T23:59:59.000Z

335

AAPM Task Group 108: PET and PET/CT Shielding Requirements  

SciTech Connect

The shielding of positron emission tomography (PET) and PET/CT (computed tomography) facilities presents special challenges. The 0.511 MeV annihilation photons associated with positron decay are much higher energy than other diagnostic radiations. As a result, barrier shielding may be required in floors and ceilings as well as adjacent walls. Since the patient becomes the radioactive source after the radiopharmaceutical has been administered, one has to consider the entire time that the subject remains in the clinic. In this report we present methods for estimating the shielding requirements for PET and PET/CT facilities. Information about the physical properties of the most commonly used clinical PET radionuclides is summarized, although the report primarily refers to fluorine-18. Typical PET imaging protocols are reviewed and exposure rates from patients are estimated including self-attenuation by body tissues and physical decay of the radionuclide. Examples of barrier calculations are presented for controlled and noncontrolled areas. Shielding for adjacent rooms with scintillation cameras is also discussed. Tables and graphs of estimated transmission factors for lead, steel, and concrete at 0.511 MeV are also included. Meeting the regulatory limits for uncontrolled areas can be an expensive proposition. Careful planning with the equipment vendor, facility architect, and a qualified medical physicist is necessary to produce a cost effective design while maintaining radiation safety standards.

Madsen, Mark T.; Anderson, Jon A.; Halama, James R. [Radiology, University of Iowa (United States)] (and others)

2006-01-15T23:59:59.000Z

336

Shielding Design for Current Sensor of Excitation System Based on 3-D FEM  

Science Conference Proceedings (OSTI)

In an excitation system of a certain type synchronous motor, current sensor for detection and protection often works under abnormal conditions. It leads to inability to play the role of the normal current detection, or even false tripping down the serious ... Keywords: Excitation system, Electromagnetic interference, Finite element method, Shielding

Huimin Liang; Jiaxin You; Xuerong Ye; Guofu Zhai; Guoliang Li; Yutao Shi

2010-09-01T23:59:59.000Z

337

Gravity anomalies of the Northern Hawaiian Islands: Implications on the shield evolutions of Kauai and Niihau  

E-Print Network (OSTI)

Gravity anomalies of the Northern Hawaiian Islands: Implications on the shield evolutions of Kauai January 2010; accepted 16 March 2010; published 31 August 2010. [1] New land and marine gravity data reveal two positive residual gravity anomalies in the Northern Hawaiian Islands: one over Kaua

Ito, Garrett

338

Neutron and gamma radiation shielding material, structure, and process of making structure  

DOE Patents (OSTI)

The present invention is directed to a novel neutron and gamma radiation elding material consisting of 95 to 97 percent by weight SiO.sub.2 and 5 to 3 percent by weight sodium silicate. In addition, the method of using this composition to provide a continuous neutron and gamma radiation shielding structure is disclosed.

Hondorp, Hugh L. (Princeton Junction, NJ)

1984-01-01T23:59:59.000Z

339

Eye-Shield: protecting bystanders from being blinded by mobile projectors  

Science Conference Proceedings (OSTI)

This paper introduces Eye-Shield, a mobile projector-camera prototype designed for the purpose of protecting people from being accidently blinded with a handheld projector. Since they might be used regularly in public space, mobile projectors can be ... Keywords: blinding light suppression, camera, face detection, mobile projector, social aspects

Bonifaz Kaufmann; Martin Hitz

2011-11-01T23:59:59.000Z

340

Simultaneous shield insertion and net ordering under explicit RLC noise constraint  

Science Conference Proceedings (OSTI)

For multiple coupled RLC nets, we formulate the min-area simultaneous shield insertion and net ordering SINO/NB-&ngr; problem to satisfy the given noise bound. We develop an efficient and conservative model to compute the peak noise, and apply the noise ...

Kevin M. Lepak; Irwan Luwandi; Lei He

2001-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Nuclear data development and shield design for neutrons below 60 MeV  

DOE Green Energy (OSTI)

A nuclear data library was created for medium-energy-neutron-transport calculations. The 60-group library includes P/sub 5/ cross sections in standard LASL format for H, B, C, N, O, Si, Fe, and W. The 60-group structure was chosen from a sensitivity analysis of a thick iron shield calculated with a 50-MeV deuteron-on-beryllium neutron source spectrum and a 121-group cross-section set. The library combines processed ENDF/B-IV cross-section data below 20 MeV and higher-energy cross-section parameters calculated with the intranuclear-cascade and evaporation model. A 6-group version of the library is used in the design of a shield-collimator unit for fast-neutron radiotherapy. While the shield is specific for the 50-MeV d/sup +/--Be neutron source presently used in cancer therapy at Texas A and M University, the cross sections and methods developed are applicable to the problems of medium-energy-neutron shielding in general. 28 figures, 21 tables, 132 references.

Wilson, W.B.

1978-02-01T23:59:59.000Z

342

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

343

Atomic Energy for Military Purposes  

E-Print Network (OSTI)

Atomic Energy for Military Purposes: The Official Report on the Development of the Atomic Bomb member of the project, to draft a report about its activities. Smyth completed the report in the summer, in a censored version. On August 11, 1945, five days after the Allies dropped the first nuclear bomb on Japan

Landweber, Laura

344

THE DEVELOPMENT OF ATOMIC LAW  

SciTech Connect

Since a uniform federal statute hss not been passed in the German Federal Republic, the development of atomic law has centered around the formation of the Federal Ministry for Atomic Affairs, appeal to the German Commission, and the enactment of temporary laws in several of the states. (J.S.R.)

Fischerhof, H.

1958-08-01T23:59:59.000Z

345

Gamma and X-ray shielding compositions utilizing bauxite - Red Mud regional research laboratory (CSIR), Bhopal, India  

SciTech Connect

Available in abstract form only. Full text of publication follows: The application spectrum of X-ray and Gamma radiation is increasing exponentially in the area of diagnostic, nuclear medicine, food preservation, nuclear power plants and strategic utilities. To prevent the harmful effects of these radiations, shielding materials based on lead metal and its compounds are being used historically, which are toxic in nature. To protect environment it has become necessary to develop non-toxic lead free shielding materials. The use of titanium metal and its compounds as synthetic rock i.e. SYNROC are reported to be very effective non-toxic shielding materials for various applications. Red mud waste generated in aluminum producing industries possesses a unique mineralogical compositions containing fairly high quantity of titanium oxide and iron oxide useful for making non toxic shielding compositions and therefore red mud has been utilized for the first time in the world for making radiation shielding materials. The red mud based compositions developed have been characterized for their various physico-mechanical properties namely compressive strength, impact strength, density and X-ray and gamma radiation shielding capacity in terms of shielding thickness i.e. HVT. Based on the characterization results it is found that the red mud based materials can be used for the construction of X-ray diagnostic and CT-Scanner room and as a substitute shielding material for concrete in the nuclear reactors and other radiation based applications. Studies on the identification of shielding phases and their morphology present, in the red mud based shielding compositions has been carried out using X-ray diffraction and SEM technique. The results of these studies are presented in this paper. (authors)

Anshul, Avneesh; Amritphale, Sudhir Sitaram; Chandra, Navin; Ramakrishnan, N. [Regional Research Laboratory, Council of Scientific and Industrial Research, Bhubaneswar 751013, Orissa (India)

2007-07-01T23:59:59.000Z

346

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

347

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

2006-06-17T23:59:59.000Z

348

Depth Profile of Radioactivity Induced in the Thick Concrete Shield in EP1 Beam Line at the KEK 12-GeV Proton Synchrotron Facility  

Science Conference Proceedings (OSTI)

Accelerators / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Measurements and Instrumentation

Norikazu Kinoshita; Hiroshi Matsumura; Kotaro Bessho; Akihiro Toyoda; Kazuyoshi Masumoto; Yuki Matsushi; Kimikazu Sasa; Tsutomu Takahashi; Shozo Mihara; Toshiyuki Oki; Masumi Matsumura; Yuki Tosaki; Keisuke Sueki; Michiko Tamari; Yasuo Nagashima

349

Construction of a Post-Irradiated Fuel Examination Shielded Enclosure Facility  

SciTech Connect

The U.S. Department of Energy (DOE) has committed to provide funding to the Idaho National Laboratory (INL) for new post-irradiation examination (PIE) equipment in support of advanced fuels development. This equipment will allow researchers at the INL to accurately characterize the behavior of experimental test fuels after they are removed from an experimental reactor also located at the INL. The accurate and detailed characterization of the fuel from the reactor, when used in conjunction with computer modeling, will allow DOE to more quickly understand the behavior of the fuel and to guide further development activities consistent with the missions of the INL and DOE. Due to the highly radioactive nature of the specimen samples that will be prepared and analyzed by the PIE equipment, shielded enclosures are required. The shielded cells will be located in the existing Analytical Laboratory (AL) basement (Rooms B-50 and B-51) at the INL Material and Fuels Complex (MFC). AL Rooms B-50 and B-51 will be modified to establish an area where sample containment and shielding will be provided for the analysis of radioactive fuels and materials while providing adequate protection for personnel and the environment. The area is comprised of three separate shielded cells for PIE instrumentation. Each cell contains an atmosphere interface enclosure (AIE) for contamination containment. The shielding will provide a work area consistent with the as-low-as-reasonably-achievable (ALARA) concept, assuming a source term of 10 samples in each of the three shielded areas. Source strength is assumed to be a maximum of 3 Ci at 0.75 MeV gamma for each sample. Each instrument listed below will be installed in an individual shielded enclosure: Shielded electron probe micro-analyzer (EPMA) Focused ion beam instrument (FIB) Micro-scale x-ray diffractometer (MXRD). The project is designed and expected to be built incrementally as funds are allocated. The initial phase will be to fund the construction activities, which will include facility modifications and construction of one shielded enclosure. Follow-up activities will be to construct two additional shielded enclosures to complete the suite of three separate but connected remote operated examination areas. Equipment purchases are to be capital procurement spread out over several years on a funded schedule. This paper discusses safety and operational considerations given during the conceptual design phase of the project. The paper considers such things as project material at risk (MAR), new processes and equipment, potential hazards, and the major modification evaluation process to determine if a preliminary Documented Safety Analysis (PDSA) is required. As part of that process, an evaluation was made of the potential hazards with the new project compared to the existing and historical work and associated hazards in the affected facility.

Michael A. Lehto, Ph.D.; Boyd D. Christensen

2008-05-01T23:59:59.000Z

350

Anticipating the atom: popular perceptions of atomic power before Hiroshima  

E-Print Network (OSTI)

Before Hiroshima made the Bomb an object of popular concern, possible implications and applications of atomic physics had been discussed in the public forum. The new science of X-rays and radium promised the possibilities of unlimited energy and the transmutation of elements in the two decades leading up to World War 1. During the twenties, as scientific method struggled to keep pace with atomic theory, discussion centered on the feasibility of atomic disintegration as an energy source and the many uses of radium. The 1927 case of the New Jersey Radium Dial Painters, who sued their employers for compensation after contracting radium poisoning, revealed a dark side to the new science, that, along with the development of artificial radioactive isotopes by the Jollot-Curies in Paris, and, in Italy, Enrico Fenni's neutron bombardment experiments, sobered attitudes toward the ever-increasing probability of atomic power. When Otto Hahn finally split the atom in 1938, it opened the way to the practical industrial use of atomic fission, and stimulated a flurry of newspaper and magazine articles before World War 11 brought about censorship. Popular entertainment through 1945 reflects the extent to which atomic power had entered the public awareness. Atomic themes and motifs appeared in English language fiction as early as 1895, as did discussions of the social implications of the new science. Such popular culture imagery, including motion pictures and comic book superheroes, that presented the atom to mass audiences provide insight into the popular perceptions at the time, and to the shaping of attitudes toward the Bomb after Hiroshima.

d'Emal, Jacques-Andre Christian

1994-01-01T23:59:59.000Z

351

FEPs Screening of Processes and Issues in Drip Shield and Waste Package Degradation  

Science Conference Proceedings (OSTI)

The purpose of this report is to evaluate and document the inclusion or exclusion of features, events and processes (FEPs) with respect to drip shield and waste package modeling used to support the Total System Performance Assessment for License Application (TSPA-LA). Thirty-three FEPs associated with the waste package and drip shield performance have been identified (DTN: MO0407SEPFEPLA.000 [DIRS 170760]). A screening decision, either ''included'' or ''excluded,'' has been assigned to each FEP, with the technical bases for screening decisions, as required by the Nuclear Regulatory Commission (NRC) in 10 CFR 63.114 (d, e, and f) [DIRS 156605]. The FEPs analyses in this report address issues related to the degradation and potential failure of the drip shield and waste package over the post closure regulatory period of 10,000 years after permanent closure. For included FEPs, this report summarizes the disposition of the FEP in TSPA-LA. For excluded FEPs, this report provides the technical bases for the screening arguments for exclusion from TSPA-LA. The analyses are for the TSPA-LA base-case design (BSC 2004 [DIRS 168489]), where a drip shield is placed over the waste package without backfill over the drip shield (BSC 2004 [DIRS 168489]). Each FEP includes one or more specific issues, collectively described by a FEP name and description. The FEP description encompasses a single feature, event, or process, or a few closely related or coupled processes, provided the entire FEP can be addressed by a single specific screening argument or TSPA-LA disposition. The FEPs were assigned to associated Project reports, so the screening decisions reside with the relevant subject-matter experts.

K. Mon

2004-10-11T23:59:59.000Z

352

Efficacy of Lower-Body Shielding in Computed Tomography Fluoroscopy-Guided Interventions  

Science Conference Proceedings (OSTI)

Purpose: Computed tomography (CT) fluoroscopy-guided interventions pose relevant radiation exposure to the interventionalist. The goal of this study was to analyze the efficacy of lower-body shielding as a simple structural method for decreasing radiation dose to the interventionalist without limiting access to the patient. Material and Methods: All examinations were performed with a 128-slice dual source CT scanner (12 Multiplication-Sign 1.2-mm collimation; 120 kV; and 20, 40, 60, and 80 mAs) and an Alderson-Rando phantom. Scatter radiation was measured with an ionization chamber and a digital dosimeter at standardized positions and heights with and without a lower-body lead shield (0.5-mm lead equivalent; Kenex, Harlow, UK). Dose decreases were computed for the different points of measurement. Results: On average, lower-body shielding decreased scatter radiation by 38.2% within a 150-cm radius around the shielding. This decrease is most significant close to the gantry opening and at low heights of 50 and 100 cm above the floor with a maximum decrease of scatter radiation of 95.9% close to the scanner's isocentre. With increasing distance to the gantry opening, the effect decreased. There is almost no dose decrease effect at {>=}150 above the floor. Scatter radiation and its decrease were linearly correlated with the tube current-time product (r{sup 2} = 0.99), whereas percent scatter radiation decrease was independent of the tube current-time product. Conclusion: Lower-body shielding is an effective way to decrease radiation exposure to the interventionalist and should routinely be used in CT fluoroscopy-guided interventions.

Mahnken, Andreas H., E-mail: mahnken@rad.rwth-aachen.de [RWTH Aachen, Department of Diagnostic and Interventional Radiology (Germany); Sedlmair, Martin [Siemens, Healthcare Sector (Germany); Ritter, Christine [University of Copenhagen, Niels Bohr Institute (Denmark); Banckwitz, Rosemarie; Flohr, Thomas [Siemens, Healthcare Sector (Germany)

2012-12-15T23:59:59.000Z

353

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

354

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 is disclosed. 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. 3 figs.

Anderson, I.E.; Figliola, R.S.; Terpstra, R.L.

1995-06-13T23:59:59.000Z

355

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

356

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

357

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

358

MODELING HEAT TRANSFER IN SPENT FUEL TRANSFER CASK NEUTRON SHIELDS – A CHALLENGING PROBLEM IN NATURAL CONVECTION  

SciTech Connect

In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 10-15 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper proposes that there may be reliable CFD approaches to the transfer cask problem, specifically coupled steady-state solvers or unsteady simulations; however, both of these solutions take significant computational effort. Segregated (uncoupled) steady state solvers that were tested did not accurately capture the flow field and heat transfer distribution in this application. Mesh resolution, turbulence modeling, and the tradeoff between steady state and transient solutions are addressed. Because of the critical nature of this application, the need for new experiments at representative scales is clearly demonstrated.

Fort, James A.; Cuta, Judith M.; Bajwa, C.; Baglietto, E.

2010-07-18T23:59:59.000Z

359

Three-dimensional analysis of AP600 standard plant shield building roof  

SciTech Connect

The AP600 passive containment vessel is surrounded by a concrete cylindrical shell covered with a truncated conical roof. This roof supports the passive containment cooling system (PCS) annular tank, shield plate and other nonstructural attachments. When the shield building is subjected to different loading combinations as defined in the Standard Review Plan (SRP), some of the sections in the shield building could experience forces in excess of their design values. This report summarized the three-dimensional finite element analysis that was conducted to review the adequacy of the proposed Westinghouse shield building design. The ANSYS finite element software was utilized to analyze the Shield Building Roof (SBR) under dead, snow, wind, thermal and seismic loadings. A three-dimensional model that included a portion of the shield building cylindrical shell, the conical roof and its attachments, the eccentricities at the cone-cylinder connection and at the compression ring and the PCS tank was developed. Mesh sensitivity studies were conducted to select appropriate element size in the cylinder, cone, near air intakes and in the vicinity of the eccentricities. Also, a study was carried out to correctly idealize the water-structure interaction in the PCS tank. Response spectrum analysis was used to calculate the internal forces at different sections in the SBR under Safe Shutdown Earthquake (SSE). Forty-nine structural modes and twenty sloshing modes were used. Two horizontal components of the SSE together with a vertical component were used. Modal stress resultants were combined taking into account the effects of closely spaced modes. The three earthquake directions were combined by the Square Root of the Sum Squares method. Two load combinations were studied. The load combination that included dead, snow, fluid, thermal and seismic loads was selected to be the most critical. Interaction diagrams for critical sections were developed and used to check the design adequacy. The results demonstrated that provided area of steal on each face of several sections of the AP600 SBR was inadequate. This was also noticed when comparing the total provided area of steel per section, i.e., the area of steel on both faces. The discrepancy between Westinghouse results and these reported herein could have resulted from the different finite element mesh sizes and the assumption used in Westinghouse design.

Greimann, L.; Fanous, F.; Safar, S.; Khalil, A.; Bluhm, D.

1999-06-01T23:59:59.000Z

360

UNITED STATES ATOMIC ENERGY COMMISSION  

Office of Legacy Management (LM)

producing uranium for the Mo"hz,t,a, Projec, can best be qwtcd Irom the Smyth official report - Atomic Energy - . ' .: CCL, + NaCl - ."-l Figure 6. apparatus used in electrcdytic...

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Single artificial-atom lasing  

E-Print Network (OSTI)

Solid-state superconducting circuits are versatile systems in which quantum states can be engineered and controlled. Recent progress in this area has opened up exciting possibilities for exploring fundamental physics as well as applications in quantum information technology; in a series of experiments it was shown that such circuits can be exploited to generate quantum optical phenomena, by designing superconducting elements as artificial atoms that are coupled coherently to the photon field of a resonator. Here we demonstrate a lasing effect with a single artificial atom - a Josephson-junction charge qubit - embedded in a superconducting resonator. We make use of one of the properties of solid-state artificial atoms, namely that they are strongly and controllably coupled to the resonator modes. The device is essentially different from existing lasers and masers; one and the same artificial atom excited by current injection produces many photons.

O. Astafiev; K. Inomata; A. O. Niskanen; T. Yamamoto; Yu. A. Pashkin; Y. Nakamura; J. S. Tsai

2007-10-04T23:59:59.000Z

362

u. S. Atomic Energy Commission  

Office of Legacy Management (LM)

October 31, 1949 Manager of Operations u. S. Atomic Energy Commission R. 0. Box 30, Ansonia Station New York ES, N. Y. MATERIALS 5+k& hJf Reference: SK:BL Attention: Mr. R. J....

363

Mechanical stability of the LHC dipole-dipole 50-75K thermal shield interconnect "floating" expansion joint concept  

E-Print Network (OSTI)

The LHC dipole cryostats are equipped with thermal shields carrying super-insulation. A cold helium transfer line equipped with expansion joints is integrated into the shield carrying trays (aluminium profiles supported on three composite feet). The stainless steel (316 L) expansion joints compensate for thermal contraction/expansion of the aluminium panels as well as for their misalignment. Design of the LHC thermal shield interconnect is based on the "floating" expansion joint concept (distance between the supports is of around 5 m). The present paper is dedicated to the analysis of mechanical stability of this large span system working at room and at cryogenic temperatures.

Skoczen, Blazej

1998-01-01T23:59:59.000Z

364

Exotic atoms and leptonic conservations  

DOE Green Energy (OSTI)

The major 1989 efforts have been on two aspects of experiments at TRIUMF. One effort was production of muonic hydrogen and muonic deuterium into a vacuum. We study rates relevant to muonic catalyzed fusion, and if there are found an adequate number of muons in the 2s state then we plan to measure precision energies. The second effort was to develop plans for kaonic atoms at the kaon factory. We also completed analyses from the experiments with pionic atoms at LAMPF.

Kunselman, R.

1990-01-01T23:59:59.000Z

365

Transition from LEDCOP to ATOMIC  

SciTech Connect

This paper discusses the development of the ATOMIC code, a new low to mid Z opacity code, which will replace the current Los Alamos low Z opacity code LEDCOP. The ATOMIC code is based on the FINE code, long used by the Los Alamos group for spectral comparisons in local thermodynamic equilibrium (LTE) and for non-LTE calculations, both utilizing the extensive databases from the atomic physics suite of codes based on the work of R.D. Cowan. Many of the plasma physics packages in LEDCOP, such as line broadening and free-free absorption, are being transferred to the new ATOMIC code. A new equation of state (EOS) model is being developed to allow higher density calculations than were possible with either the FINE or LEDCOP codes. Extensive modernization for both ATOMIC and the atomic physics code suites, including conversion to Fortran 90 and parallelization, are underway to speed up the calculations and to allow the use of expanded databases for both the LTE opacity tables and the non-LTE calculations. Future plans for the code will be outlined, including considerations for new generation opacity tables.

Magee, N. H. (Norman H.); Abdallah, J. (Joseph); Colgan, J. (James); Hakel, P. (Peter); Kilcrease, D. P. (David P.); Mazevet, S. (Stephane); Sherrill, M. E. (Manolo E.); Fontes, C. J. (Christopher J.); Zhang, H. (Honglin)

2004-01-01T23:59:59.000Z

366

Atomic Physics Division 1999 - Future Directions  

Science Conference Proceedings (OSTI)

... lying Rydberg states constitute a "frozen" Rydberg gas. ... of atom interactions in cold atomic gases and Bose ... or optical fields and tight confinement of ...

367

Cavity Quantum Electrodynamics with Ultracold Atoms.  

E-Print Network (OSTI)

??Die vorliegende Arbeit befasst sich mit der Wechselwirkung ultrakalter Atome mit der Mode eines optischen Resonators hoher Gu?te. Die Atome sind dabei in einem periodischen… (more)

Habibian, Hessam

2013-01-01T23:59:59.000Z

368

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)

369

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; McConchie, Seth M [ORNL; Crye, Jason Michael [ORNL; Mihalczo, John T [ORNL

2011-01-01T23:59:59.000Z

370

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. 10 figs.

Cookson, A.H.; Dale, S.J.; Bolin, P.C.

1982-12-28T23:59:59.000Z

371

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

DOE Patents (OSTI)

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

372

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

373

Control schemes for an industrial rotary calciner with a heat shield around the combustion zone  

SciTech Connect

Soda ash (sodium carbonate) is produced by calcining natural trona ore (sodium sesquicarbonate) in rotary calciners. Shell overheating, the consequent deformation of the calciner shell, and heat loss are frequently encountered problems during this operation. Installation of a concentric, metallic heat shield around the calciner`s combustion zone can help to reduce the shell temperature and recover some of the energy that would otherwise be lost. Another problem often encountered is the deterioration of product quality when the system inputs deviate from their design rates. A mathematical model of the calciner with a heat shield is used to design different control schemes in order to maintain the product quality. Performance of the designed control schemes is demonstrated via computer simulation.

Ciftci, S.; Kim, N.K. [Michigan Technological Univ., Houghton, MI (United States). Dept. of Chemical Engineering] [Michigan Technological Univ., Houghton, MI (United States). Dept. of Chemical Engineering

1999-03-01T23:59:59.000Z

374

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

375

A Potent and Broad Neutralizing Antibody Recognizes and Penetrates the HIV Glycan Shield  

SciTech Connect

The HIV envelope (Env) protein gp120 is protected from antibody recognition by a dense glycan shield. However, several of the recently identified PGT broadly neutralizing antibodies appear to interact directly with the HIV glycan coat. Crystal structures of antigen-binding fragments (Fabs) PGT 127 and 128 with Man{sub 9} at 1.65 and 1.29 angstrom resolution, respectively, and glycan binding data delineate a specific high mannose-binding site. Fab PGT 128 complexed with a fully glycosylated gp120 outer domain at 3.25 angstroms reveals that the antibody penetrates the glycan shield and recognizes two conserved glycans as well as a short {beta}-strand segment of the gp120 V3 loop, accounting for its high binding affinity and broad specificify. Furthermore, our data suggest that the high neutralization potency of PGT 127 and 128 immunoglobulin Gs may be mediated by cross-linking Env trimers on the viral surface.

Pejchal, Robert; Doores, Katie J.; Walker, Laura M.; Khayat, Reza; Huang, Po-Ssu; Wang, Sheng-Kai; Stanfield, Robyn L.; Julien, Jean-Philippe; Ramos, Alejandra; Crispin, Max; Depetris, Rafael; Katpally, Umesh; Marozsan, Andre; Cupo, Albert; Maloveste, Sebastien; Liu, Yan; McBride, Ryan; Ito, Yukishige; Sanders, Rogier W.; Ogohara, Cassandra; Paulson, James C.; Feizi, Ten; Scanlan, Christopher N.; Wong, Chi-Huey; Moore, John P.; Olson, William C.; Ward, Andrew B.; Poignard, Pascal; Schief, William R.; Burton, Dennis R.; Wilson, Ian A. (Progenics); (JSTA); (UWASH); (Scripps); (NIH); (Weill); (Oxford); (ICL)

2011-12-05T23:59:59.000Z

376

OPTICAL PROPERTIES OF THE SHIELDING WINDOWS OF Co-60 GAMMA RADIATION FACILITY  

SciTech Connect

Shielding windows manufactured by Corning, Penberthy, and Nippon Kogaku Co. were examined. Bubbles, stones, and scratches were found in all three windows in considerable quantity, and striae were found in the windows of Penberthy and Nippon Kogaku. Transmittances of the windows measured for D-line were about 25% for Nippon Kogaku's, 25% for Corning's, and 14% for Penberthy's. (W.D.M.)

Danno, A.; Yamamoto, K.; Yamaguchi, I.; Kawarazaki, Y.

1959-01-01T23:59:59.000Z

377

CSER 95-002: ALARA shielding for IAEA SNM container movement  

Science Conference Proceedings (OSTI)

This CSER qualifies use of a 5% borated, lead foil lined polyethylene 1 inch annulus as a bucket and in a small carrier to move sealed containers of plutonium. The containers are Oversize Cans or smaller containing plutonium limited in mass and H/Pu ratio by PFP storage and transportation CPS`s. These ALARA shielding units reduce personnel exposure to the radiation from the containers as they are moved for assay and other required activities.

Miller, E.M.

1995-03-07T23:59:59.000Z

378

Radiation shielding tests in the Meson beamline in the master substation area  

SciTech Connect

A review of shielding uncovered a weak region in a portion of the proton beam transport to the Meson Area. Preliminary CASIM Monte Carlo studies indicated dose rates at the surface under abnormal operating conditions would be above the Fermilab Radiation Guide limits. Measurements made on December 15 and 16 confirmed this concern. Further comparisons of data with CASIM predictions are discussed. 5 refs., 22 figs., 8 tabs.

Coleman, R.; Kissel, W.; Leveling, A.; Moore, C.D.; Vylet, V.

1991-04-01T23:59:59.000Z

379

Radiation shielding issues for MuCool test area at Fermilab  

DOE Green Energy (OSTI)

The MuCool Test Area (MTA) is an intense primary beam facility derived directly from the Fermilab Linac to test heat deposition and other technical concerns associated with the liquid hydrogen targets being developed for cooling intense muon beams. In this study the origin of the outgoing collimated neutron beam is examined. An alternative shielding option for MTA is investigated as well as the hypothetical worst case of experimental setup is considered.

Rakhno, I.; Johnstone, C.; /Fermilab

2005-03-01T23:59:59.000Z

380

Structural analysis of an LMFBR shield assembly duct under thermo-mechanical and seismic loads  

SciTech Connect

This paper describes the stress analysis performed to assess structural adequacy of the Clinch River Breeder Reactor (CRBR) core removable shield assemblies. Removable shield assemblies are located in the peripheral region of the core (between blanket assemblies and the fixed radial shield), and are subjected to severe cross-sectional thermal gradients and seismic loads requiring a relatively complex duct load pad design. For cost-effectiveness, the analysis was conducted in two stages. First, an elasto-plastic seismic stress analysis was performed using a detailed nonlinear finite element model (with gaps) of the load pad configuration. Next, in order to determine the total strain accumulation and the creep-fatigue damage the maximum seismic stresses combined with the ''worst'' thermal stresses from a single assembly model were used to perform a simplified inelastic analysis using two sets of material properties to bound the changing material conditions during reactor operation. This work demonstrated the necessity and applicability of the two simplified analysis techniques in elevated temperature structural design, i.e., the treatment of time-dependent degradation of material properties due to temperature and nuclear irradiation, and the use of time-independent finite element stress analysis results to perform a simplified creep-fatigue analysis.

Malik, S.N.; Sazawal, V.K.

1984-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Monte Carlo simulation of photon buildup factors for shielding materials in diagnostic x-ray facilities  

SciTech Connect

Purpose: A simulation of buildup factors for ordinary concrete, steel, lead, plate glass, lead glass, and gypsum wallboard in broad beam geometry for photons energies from 10 keV to 150 keV at 5 keV intervals is presented. Methods: Monte Carlo N-particle radiation transport computer code has been used to determine the buildup factors for the studied shielding materials. Results: An example concretizing the use of the obtained buildup factors data in computing the broad beam transmission for tube potentials at 70, 100, 120, and 140 kVp is given. The half value layer, the tenth value layer, and the equilibrium tenth value layer are calculated from the broad beam transmission for these tube potentials. Conclusions: The obtained values compared with those calculated from the published data show the ability of these data to predict shielding transmission curves. Therefore, the buildup factors data can be combined with primary, scatter, and leakage x-ray spectra to provide a computationally based solution to broad beam transmission for barriers in shielding x-ray facilities.

Kharrati, Hedi; Agrebi, Amel; Karoui, Mohamed Karim [Ecole Superieure des Sciences et Techniques de la Sante de Monastir, Avenue Avicenne, 5000 Monastir (Tunisia); Faculte des Sciences de Monastir, 5000 Monastir (Tunisia)

2012-10-15T23:59:59.000Z

382

Using Electronic Neutron Generators in Active Interrogation to Detect Shielded Fissionable Material  

Science Conference Proceedings (OSTI)

Experiments have been performed at Idaho National Laboratory to study methodology and instrumentation for performing neutron active interrogation die-away analyses for the purpose of detecting shielded fissionable material. Here we report initial work using a portable DT electronic neutron generator with a He-3 fast neutron detector to detect shielded fissionable material including >2 kg quantities of enriched uranium and plutonium. Measurements have been taken of bare material as well as of material hidden within a large plywood cube. Results from this work have demonstrated the efficacy of the die-away neutron measurement technique for quickly detecting the presence of special nuclear material hidden within plywood shields by analyzing the time dependent neutron signals in-between neutron generator pulses. Using a DT electronic neutron generator operating at 300 Hz with a yield of approximately 0.36 x 10**8 neutrons per second, 2.2 kg of enriched uranium hidden within a 0.60 m x 0.60 m x 0.70 m volume of plywood was positively detected with a measurement signal 2-sigma above the passive background within 1 second. Similarly, for a 500 second measurement period a lower detection limit of approaching the gram level could be expected with the same simple set-up.

D. L. Chichester; E. H. Seabury

2008-10-01T23:59:59.000Z

383

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

DOE Green Energy (OSTI)

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

384

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

DOE Green Energy (OSTI)

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

385

Orthogonally interdigitated shielded serpentine travelling wave cathode ray tube deflection structure  

DOE Patents (OSTI)

A new deflection structure (12) which deflects a beam of charged particles, uch as an electron beam (15), includes a serpentine set (20) for transmitting a deflection field, and a shielding frame (25) for housing the serpentine set (20). The serpentine set (20) includes a vertical serpentine deflection element (22) and a horizontal serpentine deflection element (24). These deflection elements (22, 24) are identical, and are interdigitatedly and orthogonally disposed relative to each other, for forming a central transmission passage (75), through which the electron beam (15) passes, and is deflected by the deflection field, so as to minimize drift space signal distortion. The shielding frame (25) includes a plurality of ground blocks (26, 28, 30, 32), and forms an internal serpentine trough (77) within these ground blocks, for housing the serpentine set (20). The deflection structure (12) further includes a plurality of feedthrough connectors (35, 37, 35I, 37I), which are inserted through the shielding frame (25), and which are electrically connected to the serpentine set (20).

Hagen, Edward C. (Las Vegas, NV); Hudson, Charles L. (Santa Barbara, CA)

1995-01-01T23:59:59.000Z

386

Thermal Characteristics and Energy Balance of Various-Size Canadian Shield Lakes in the Mackenzie River Basin  

Science Conference Proceedings (OSTI)

This study addresses the thermal and energy budget characteristics of four different-size Canadian Shield lakes in the Mackenzie River basin during the ice-free season of 2000. The objectives are to characterize and compare the surface ...

Claire J. Oswald; Wayne R. Rouse

2004-02-01T23:59:59.000Z

387

REACTOR AND SHIELD PHYSICS. Comprehensive Technical Report, General Electric Direct-Air-Cycle, Aircraft Nuclear Propulsion Program.  

SciTech Connect

This volume is one of twenty-one summarizing the Aircraft Nuclear Propulsion Program of the General Electric Company. This volume describes the experimental and theoretical work accomplished in the areas of reactor and shield physics.

Edwards, W.E.; Simpson, J.D.

1962-01-01T23:59:59.000Z

388

Conduction Effect of Thermal Radiation in a Metal Shield Pipe in a Cryostat for a Cryogenic Interferometric Gravitational Wave Detector  

E-Print Network (OSTI)

A large heat load caused by thermal radiation through a metal shield pipe was observed in a cooling test of a cryostat for a prototype of a cryogenic interferometric gravitational wave detector. The heat load was approximately 1000 times larger than the value calculated by the Stefan-Boltzmann law. We studied this phenomenon by simulation and experiment and found that it was caused by the conduction of thermal radiation in a metal shield pipe.

Takayuki Tomaru; Masao Tokunari; Kazuaki Kuroda; Takashi Uchiyama; Akira Okutomi; Masatake Ohashi; Hiroyuki Kirihara; Nobuhiro Kimura; Yoshio Saito; Nobuaki Sato; Takakazu Shintomi; Toshikazu Suzuki; Tomiyoshi Haruyama; Shinji Miyoki; Kazuhiro Yamamoto; Akira Yamamoto

2007-11-06T23:59:59.000Z

389

Electromagnetic analysis of forces and torques on the baseline and enhanced ITER shield modules due to plasma disruption.  

SciTech Connect

An electromagnetic analysis is performed on the ITER shield modules under different plasma-disruption scenarios using the OPERA-3d software. The models considered include the baseline design as provided by the International Organization and an enhanced design that includes the more realistic geometrical features of a shield module. The modeling procedure is explained, electromagnetic torques are presented, and results of the modeling are discussed.

Kotulski, Joseph Daniel; Coats, Rebecca Sue; Pasik, Michael Francis; Ulrickson, Michael Andrew

2009-08-01T23:59:59.000Z

390

Space reactor system and subsystem investigations: assessment of technology issues for the reactor and shield subsystem. SP-100 Program  

SciTech Connect

As part of Rockwell's effort on the SP-100 Program, preliminary assessment has been completed of current nuclear technology as it relates to candidate reactor/shield subsystems for the SP-100 Program. The scope of the assessment was confined to the nuclear package (to the reactor and shield subsystems). The nine generic reactor subsystems presented in Rockwell's Subsystem Technology Assessment Report, ESG-DOE-13398, were addressed for the assessment.

Atkins, D.F.; Lillie, A.F.

1983-06-30T23:59:59.000Z

391

Observation of relativistic antihydrogen atoms  

DOE Green Energy (OSTI)

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

392

NIST: Atomic Spectros. - Spectral Continuum Radiation  

Science Conference Proceedings (OSTI)

Atomic Spectroscopy: home page. 21. Spectral Continuum Radiation. Hydrogenic Species. Precise quantum-mechanical ...

393

SCHROEDINGER'S CAT IN AN ATOMIC CAGE  

Science Conference Proceedings (OSTI)

... gov SCHROEDINGER'S CAT IN AN ATOMIC CAGE. They ... conditions. Schroedinger cat states are extremely fragile. Any ...

394

Cancer in atomic bomb survivors  

SciTech Connect

Radiation carcinogenesis was first noted in studies of individuals with occupational or therapeutic exposure to radiation. Data from long-term follow-up studies of atomic bomb survivors in Hiroshima and Nagasaki have greatly enhanced our knowledge of radiation carcinogenesis. This book presents current results obtained from epidemiological studies and pathological studies on cancer among atomic bomb survivors. It includes a description of the dosimetry system which is currently being revised. Although many of the details about radiation carcinogenesis remain unknown or uncertain, it is clear that the incidence of radiation-induced cancer among atomic bomb survivors continues unabated 40 years after exposure. Recent increases in occupational and environmental exposure to radiation together with the need for a thorough review of radiation protection standards have led to increased recognition of the importance of research on radiation carcinogenesis and risk assessment.

Shigematsu, I.; Kagan, A.

1986-01-01T23:59:59.000Z

395

Hot atom chemistry and radiopharmaceuticals  

Science Conference Proceedings (OSTI)

The chemical products made in a cyclotron target are a combined result of the chemical effects of the nuclear transformation that made the radioactive atom and the bulk radiolysis in the target. This review uses some well-known examples to understand how hot atom chemistry explains the primary products from a nuclear reaction and then how radiation chemistry is exploited to set up the optimal product for radiosynthesis. It also addresses the chemical effects of nuclear decay. There are important principles that are common to hot atom chemistry and radiopharmaceutical chemistry. Both emphasize short-lived radionuclides and manipulation of high specific activity nuclides. Furthermore, they both rely on radiochromatographic separation for identification of no-carrieradded products.

Krohn, Kenneth A.; Moerlein, Stephen M.; Link, Jeanne M.; Welch, Michael J. [University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States); Washington University, Department of Radiology, Division of Radiological Sciences, 510 South Kingshighway, St. Louis, MO 63110 (United States); University of Washington, Department of Radiology, Molecular Imaging Center, 1959 NE Pacific St., Box 356004, Seattle, WA 98195-6004 (United States); Washington University, Department of Radiology, Division of Radiological Sciences, 510 South Kingshighway, St. Louis, MO 63110 (United States)

2012-12-19T23:59:59.000Z

396

Degeneracy Breaking of Hydrogen Atom  

E-Print Network (OSTI)

The three dimensional rotation group, SO(3), is a symmetry group of the normal hydrogen atom. Each reducible representation of this group can be associated with a degenerate energy level. If this atom is placed in an external magnetic field, the interaction between the orbital magnetic moment with this field will lead to a symmetry breaking where the symmetry group of the atom is a new group distinct from the SO(3) group. This phenomenon describes the normal Zeeman effect, where a degenerate energy level splits into several new energy levels. It is explicitly shown that each of the new energy levels can be associated with an irreducible representation of the new symmetry group.

Agung Trisetyarso; Pantur Silaban

2008-12-22T23:59:59.000Z

397

Supercomputers and atomic physics data  

SciTech Connect

The advent of the supercomputer has dramatically increased the possibilities for generating and using massive amounts of detailed fine structure atomic physics data. Size, speed, and software have made calculations which were impossible just a few years ago into a reality. Further technological advances make future possibilities seem endless. The cornerstone atomic structure codes of R.D. Cowan have been adapted into a single code CATS for use on Los Alamos supercomputers. We provide a brief overview of the problem; and report a sample CATS calculation using configuration interaction to calculate collision and oscillator strengths for over 300,000 transitions in neutral nitrogen. We also discuss future supercomputer needs. 2 refs.

Abdallah, J. Jr.; Clark, R.E.H.

1988-01-01T23:59:59.000Z

398

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. 3 figs.

Becker, F.E.; Smolensky, L.S.; Balsavich, J.

1989-11-01T23:59:59.000Z

399

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

400

Dynamical polarization in pionic atoms  

SciTech Connect

Dynamical nuclear polarization occurs in pionic atoms when a nuclear excitation of appropriate multipolarity is nearly degenerate with de-excitation of a pion atomic level. This phenomenon has been studied in several nuclei, one goal being to test the pion optical potential for pion atomic states normally ''hidden'' because of pion absorption. We find that, in addition to Coulomb mixing of the atomic and nuclear levels, strong interaction mixing and nuclear excitations above the lowest collective quadrupole mode are important for understanding the experimental results. All cases except /sup 110/Pd can then be understood. For /sup 110/Pd, additional nuclear structure information is needed to determine whether or not the conventional pion optical potential will suffice again. We discuss the sensitivity of dynamical polarization measurements to the parameters of the optical potential and to various aspects of nuclear structure. In particular, we find that pionic /sup 150/Sm provides a test of the interacting boson model and that the difference in neutron and proton radii predicted by Hartree-Fock calculations affects the mixing appreciably.

Dubach, J.F.; Moniz, E.J.; Nixon, G.D.

1979-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Lesson 6- Atoms to Electricity  

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

Most power plants make electricity by boiling water to make steam that turns a turbine. A nuclear power plant works this way, too. At a nuclear power plant, splitting atoms produce the heat to boil the water. This lesson covers inside the reactor, fission control and electricity generation.

402

A user`s manual for MASH 1.0: A Monte Carlo Adjoint Shielding Code System  

Science Conference Proceedings (OSTI)

The Monte Carlo Adjoint Shielding Code System, MASH, calculates neutron and gamma-ray environments and radiation protection factors for armored military vehicles, structures, trenches, and other shielding configurations by coupling a forward discrete ordinates air-over-ground transport calculation with an adjoint Monte Carlo treatment of the shielding geometry. Efficiency and optimum use of computer time are emphasized. The code system include the GRTUNCL and DORT codes for air-over-ground transport calculations, the MORSE code with the GIFT5 combinatorial geometry package for adjoint shielding calculations, and several peripheral codes that perform the required data preparations, transformations, and coupling functions. MASH is the successor to the Vehicle Code System (VCS) initially developed at Oak Ridge National Laboratory (ORNL). The discrete ordinates calculation determines the fluence on a coupling surface surrounding the shielding geometry due to an external neutron/gamma-ray source. The Monte Carlo calculation determines the effectiveness of the fluence at that surface in causing a response in a detector within the shielding geometry, i.e., the ``dose importance`` of the coupling surface fluence. A coupling code folds the fluence together with the dose importance, giving the desired dose response. The coupling code can determine the dose response a a function of the shielding geometry orientation relative to the source, distance from the source, and energy response of the detector. This user`s manual includes a short description of each code, the input required to execute the code along with some helpful input data notes, and a representative sample problem (input data and selected output edits) for each code.

Johnson, J.O. [ed.

1992-03-01T23:59:59.000Z

403

THE SURVEY OF H I IN EXTREMELY LOW-MASS DWARFS (SHIELD)  

SciTech Connect

We present first results from the Survey of H I in Extremely Low-mass Dwarfs (SHIELD), a multi-configuration Expanded Very Large Array (EVLA) study of the neutral gas contents and dynamics of galaxies with H I masses in the 10{sup 6}-10{sup 7} M{sub sun} range detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey. We describe the survey motivation and concept demonstration using Very Large Array imaging of six low-mass galaxies detected in early ALFALFA data products. We then describe the primary scientific goals of SHIELD and present preliminary EVLA and WIYN 3.5 m imaging of the 12 SHIELD galaxies. With only a few exceptions, the neutral gas distributions of these extremely low-mass galaxies are centrally concentrated. In only one system have we detected H I column densities higher than 10{sup 21} cm{sup -2}. Despite this, the stellar populations of all of these systems are dominated by blue stars. Further, we find ongoing star formation as traced by H{alpha} emission in 10 of the 11 galaxies with H{alpha} imaging obtained to date. Taken together these results suggest that extremely low-mass galaxies are forming stars in conditions different from those found in more massive systems. While detailed dynamical analysis requires the completion of data acquisition, the most well-resolved system is amenable to meaningful position-velocity analysis. For AGC 749237, we find well-ordered rotation of 30 km s{sup -1} at {approx}40'' distance from the dynamical center. At the adopted distance of 3.2 Mpc, this implies the presence of a {approx}>1 x 10{sup 8} M{sub sun} dark matter halo and a baryon fraction {approx}<0.1.

Cannon, John M.; Engstrom, Eric; Allan, John; Erny, Grace; Fliss, Palmer; Smith, AnnaLeigh [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States)

2011-09-20T23:59:59.000Z

404

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

405

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

Science Conference Proceedings (OSTI)

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

406

Elimination of Heat-Shielding for Geothermal Tools Operating Up To 300 Degress Celsius  

DOE Green Energy (OSTI)

This report focuses Sandia National Laboratories' effort to create high-temperature logging tools for geothermal applications not requiring heat-shielding. Tool electronics can operate up to 300 C with a few limiting components operating to 250 C. Second generation electronics are needed to increase measurement accuracy and extend the operating range to 300 and then 350 C are identified. Custom development of high-temperature batteries and assembling techniques are touched on. Outcomes of this work are discussed and new directions for developing high-temperature industry are suggested.

HENFLING,JOSEPH A.; NORMANN,RANDY A.

1999-10-07T23:59:59.000Z

407

Seismic and cask drop excitation evaluation of the tower shielding reactor  

SciTech Connect

During the current shutdown of the Tower Shielding Reactor II (TSR-II), analyses were performed to determine the effect of nearby cask drops on the structural and mechanical integrity of the reactor. This evaluation was then extended to include the effects of earthquakes. Several analytic models were developed to simulate the effects of earthquake and cask drop excitation. A coupled soil-structure model was developed. As a result of the analyses, several hardware modifications and enhancements were implemented to ensure reactor integrity during future operations. 6 figs.

Harris, S.P.; Stover, R.L.; Johnson, J.J.; Sumodobila, B.N. (EQE, Inc., San Francisco, CA (USA); Oak Ridge National Lab., TN (USA); EQE, Inc., San Francisco, CA (USA))

1989-01-01T23:59:59.000Z

408

FELIX: an experimental facility to study electromagnetic effects for first wall, blanket, and shield systems  

Science Conference Proceedings (OSTI)

As part of the DOE First Wall/Blanket/Shield (FW/B/S) Engineering Test Program, Argonne National Laboratory (ANL) is carrying out an experimental program to study electromagnetic effects. Electromagnetic effect in a FW/B/S system include time delay of equilibrium field penetration to the plasma, forces and torques, eddy current heating, and electrical arcing. Such effects can arise in a fusion reactor from plasma disruption and normal and abnormal charge and discharge of the magnets. The facility will consist primarily of a solenoid magnet, a surrounding pulsed dipole magnet, and associated power supplies and support structure.

Praeg, W.F.; Turner, L.R.; Biggs, J.; Bywater, J.; Fuja, R.; Knott, M.; Lari, R.J.; McGhee, D.G.; Wehrle, R.B.

1981-01-01T23:59:59.000Z

409

Magneto-Optical Cooling of Atoms  

E-Print Network (OSTI)

We propose an alternative method to laser cooling. Our approach utilizes the extreme brightness of a supersonic atomic beam, and the adiabatic atomic coilgun to slow atoms in the beam or to bring them to rest. We show how internal-state optical pumping and stimulated optical transitions, combined with magnetic forces can be used to cool the translational motion of atoms. This approach does not rely on momentum transfer from photons to atoms, as in laser cooling. We predict that our method can surpass laser cooling in terms of flux of ultra-cold atoms and phase-space density, with lower required laser power and reduced complexity.

Raizen, Mark G; Rochester, Simon; Narevicius, Julia; Narevicius, Edvardas

2013-01-01T23:59:59.000Z

410

Atomic physics and non-equilibrium plasmas  

DOE Green Energy (OSTI)

Three lectures comprise the report. The lecture, Atomic Structure, is primarily theoretical and covers four topics: (1) Non-relativistic one-electron atom, (2) Relativistic one-electron atom, (3) Non-relativistic many-electron atom, and (4) Relativistic many-electron atom. The lecture, Radiative and Collisional Transitions, considers the problem of transitions between atomic states caused by interactions with radiation or other particles. The lecture, Ionization Balance: Spectral Line Shapes, discusses collisional and radiative transitions when ionization and recombination processes are included. 24 figs., 11 tabs.

Weisheit, J.C.

1986-04-25T23:59:59.000Z

411

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

412

Atomic vapor laser isotope separation  

SciTech Connect

Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.

Stern, R.C.; Paisner, J.A.

1985-11-08T23:59:59.000Z

413

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

414

Pulsed, Photonuclear-induced, Neutron Measurements of Nuclear Materials with Composite Shielding  

SciTech Connect

Active measurements were performed using a 10-MeV electron accelerator with inspection objects containing various nuclear and nonnuclear materials available at the Idaho National Laboratory’s Zero Power Physics Reactor (ZPPR) facility. The inspection objects were assembled from ZPPR reactor plate materials to evaluate the measurement technologies for the characterization of plutonium, depleted uranium or highly enriched uranium shielded by both nuclear and non-nuclear materials. A series of pulsed photonuclear, time-correlated measurements were performed with unshielded calibration materials and then compared with the more complex composite shield configurations. The measurements used multiple 3He detectors that are designed to detect fission neutrons between pulses of an electron linear accelerator. The accelerator produced 10-MeV bremsstrahlung X-rays at a repetition rate of 125 Hz (8 ms between pulses) with a 4-us pulse width. All inspected objects were positioned on beam centerline and 100 cm from the X-ray source. The time-correlated data was collected in parallel using both a Los Alamos National Laboratory-designed list-mode acquisition system and a commercial multichannel scaler analyzer. A combination of different measurement configurations and data analysis methods enabled the identification of each object. This paper describes the experimental configuration, the ZPPR inspection objects used, and the various measurement and analysis results for each inspected object.

James Jones; Kevin Haskell; Rich Waston; William Geist; Jonathan Thron; Corey Freeman; Martyn Swinhoe; Seth McConchie; Eric Sword; Lee Montierth; John Zabriskie

2011-07-01T23:59:59.000Z

415

Dendrite-Free Lithium Deposition via Self-Healing Electrostatic Shield Mechanism  

SciTech Connect

Lithium metal batteries are called the “holy grail” of energy storage systems. However, lithium dendrite growth in these batteries has prevented their practical applications in the last 40 years. Here we show a novel mechanism which can fundamentally change the dendritic morphology of lithium deposition. A low concentration of the second cations (including ions of cesium, rubidium, potassium, and strontium) exhibits an effective reduction potential lower than the standard reduction potential of lithium ions when the chemical activities of these second cations are much lower than that of lithium ions. During lithium deposition, these second cations will form a self-healing electrostatic shield around the initial tip of lithium whenever it is formed. This shield will repel the incoming lithium ions and force them to deposit in the smoother region of the anode so a dendrite-free film is obtained. This mechanism is effective on dendrite prevention in both lithium metal and lithium ion batteries. They may also prevent dendrite growth in other metal batteries and have transformational impact on the smooth deposition in general electrodeposition processes.

Ding, Fei; Xu, Wu; Graff, Gordon L.; Zhang, Jian; Sushko, Maria L.; Chen, Xilin; Shao, Yuyan; Engelhard, Mark H.; Nie, Zimin; Xiao, Jie; Liu, Xingjiang; Sushko, P. V.; Liu, Jun; Zhang, Jiguang

2013-02-28T23:59:59.000Z

416

Environment on the Surfaces of the Drip Shield and Waste Package Outer Barrier  

Science Conference Proceedings (OSTI)

This report provides supporting analysis of the conditions at which an aqueous solution can exist on the drip shield or waste package surfaces, including theoretical underpinning for the evolution of concentrated brines that could form by deliquescence or evaporation, and evaluation of the effects of acid-gas generation on brine composition. This analysis does not directly feed the total system performance assessment for the license application (TSPA-LA), but supports modeling and abstraction of the in-drift chemical environment (BSC 2004 [DIRS 169863]; BSC 2004 [DIRS 169860]). It also provides analyses that may support screening of features, events, and processes, and input for response to regulatory inquiries. This report emphasizes conditions of low relative humidity (RH) that, depending on temperature and chemical conditions, may be dry or may be associated with an aqueous phase containing concentrated electrolytes. Concentrated solutions at low RH may evolve by evaporative concentration of water that seeps into emplacement drifts, or by deliquescence of dust on the waste package or drip shield surfaces. The minimum RH for occurrence of aqueous conditions is calculated for various chemical systems based on current understanding of site geochemistry and equilibrium thermodynamics. The analysis makes use of known characteristics of Yucca Mountain waters and dust from existing tunnels, laboratory data, and relevant information from the technical literature and handbooks.

T. Wolery

2005-02-22T23:59:59.000Z

417

A CONCEPTUAL DESIGN OF A SHIELD TESTING AND MATERIALS IRRADIATION FACILITY  

SciTech Connect

A conceptual design is presented for a test reactor facility to be used for shielding experiments and component irradintions necessary for airframe development for the nuclear airplane program. To meet both requirements a modified swimming-pool reactor is used, with a dry irradintion cell of 320 cu ft of useful volume provided for component testing, while shielding experiments are performed in the pool in the usual manner. A BSR-type core is operated at 1 MW to provide a fest neutron flux in the irradiation cell of 10/sup 12/n/cm/sup 2/ sec at the core face and 10/sup 11/at a distance of 4 feet. The irradiation-cell facility is designed to avoid the need of remote operations in making up service connections to the experimental piece. The reactor is contained in a cylindrical building designed for 6 psi internal pressure to meet the conditions of the maximum credible accident. The estimated cost of the facility, including the reactor and the fabrication cost for an initial fuel charge, is 874,000. (auth)

Frankfort, J.H.

1956-11-20T23:59:59.000Z

418

Nuclear reactor removable radial shielding assembly having a self-bowing feature  

DOE Patents (OSTI)

A removable radial shielding assembly for use in the periphery of the core of a liquid-metal-cooled fast-breeder reactor, for closing interassembly gaps in the reactor core assembly load plane prior to reactor criticality and power operation to prevent positive reactivity insertion. The assembly has a lower nozzle portion for inserting into the core support and a flexible heat-sensitive bimetallic central spine surrounded by blocks of shielding material. At refueling temperature and below the spine is relaxed and in a vertical position so that the tolerances permitted by the interassembly gaps allow removal and replacement of the various reactor core assemblies. During an increase in reactor temperature from refueling to hot standby, the bimetallic spine expands, bowing the assembly toward the core center line, exerting a radially inward gap-closing-force on the above core load plane of the reactor core assembly, closing load plane interassembly gaps throughout the core prior to startup and preventing positive reactivity insertion.

Pennell, William E. (Greensburg, PA); Kalinowski, Joseph E. (Smithton, PA); Waldby, Robert N. (New Stanton, PA); Rylatt, John A. (Monroeville, PA); Swenson, Daniel V. (Greensburg, PA)

1978-01-01T23:59:59.000Z

419

Role of atomic collisions in fusion  

SciTech Connect

Atomic physics issues have played a large role in controlled fusion research. A general discussion of the present role of atomic processes in both magnetic and inertial controlled fusion work is presented.

Post, D.E.

1982-04-01T23:59:59.000Z

420

NIST Atomic Form Factors: Summary of uncertainties  

Science Conference Proceedings (OSTI)

... element. This "H92 - 3/5CL" value is 1.09 e/atom for uranium or 0.002 e/atom for Z = 6 (ie, 40 % of the dipole correction). ...

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Laser cooling and trapping of neutral atoms*  

Science Conference Proceedings (OSTI)

... 1 m/s, any gas in equilibrium (other than spin-polarized atomic hydro- ... lattice-trapped atoms, a physical picture with the simplicity and power of the ...

2010-08-23T23:59:59.000Z

422

Atomic vapor laser isotope separation process  

DOE Patents (OSTI)

A laser spectroscopy system is utilized in an atomic vapor laser isotope separation process. The system determines spectral components of an atomic vapor utilizing a laser heterodyne technique. 23 figs.

Wyeth, R.W.; Paisner, J.A.; Story, T.

1990-08-21T23:59:59.000Z

423

NIST: Atomic Spectroscopy Group - Past News  

Science Conference Proceedings (OSTI)

... of Atomic, Molecular, and Optical Physics of the American Physical Society (DAMOP) in ... and Determination of Relative Nuclear Charge Radius.". ...

2013-06-06T23:59:59.000Z

424

Towards a high-precision atomic gyroscope  

E-Print Network (OSTI)

In this thesis, I report on the design and construction of the Rubidium Atomic Gyroscope Experiment (RAGE) at Draper Lab.

Van Camp, Mackenzie A. (Mackenzie Anne)

2013-01-01T23:59:59.000Z

425

Argonne Chemical Sciences & Engineering - Institute for Atom...  

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

Catalysis & Energy Conversion Electrochemical Energy Storage Nuclear & Environmental Processes National Security Institute for Atom-Efficient Chemical Transformations Center for...

426

Atomic Scale Deformation Mechanisms of Amorphous Polyethylene ...  

Science Conference Proceedings (OSTI)

Atomic Scale Deformation Mechanisms of Amorphous Polyethylene under Tensile Loading · Atomistic Predictions of Age Hardening in Al-Cu Alloys.

427

NIST: Atomic Spectroscopy Group - John Curry  

Science Conference Proceedings (OSTI)

... chemical equilibrium and deviations from thermodynamic equilibrium. I am also interested in the acquisition and compilation of basic atomic data. ...

2011-02-09T23:59:59.000Z

428

NIST Atomic Physics Division 2000 - Technical Highlights  

Science Conference Proceedings (OSTI)

... Astrophysical Quantities," a handbook widely used ... and single-atom chemistry, where controlled ... understanding of fundamental processes occurring ...

429

Parametric Evaluation of Active Neutron Interrogation for the Detection of Shielded Highly-Enriched Uranium in the Field  

SciTech Connect

Parametric studies using numerical simulations are being performed to assess the performance capabilities and limits of active neutron interrogation for detecting shielded highly enriched uranium (HEU). Varying the shield material, HEU mass, HEU depth inside the shield, and interrogating neutron source energy, the simulations account for both neutron and photon emission signatures from the HEU with resolution in both energy and time. The results are processed to represent different irradiation timing schemes and several different classes of radiation detectors, and evaluated using a statistical approach considering signal intensity over background. This paper describes the details of the modeling campaign and some preliminary results, weighing the strengths of alternative measurement approaches for the different irradiation scenarios.

D. L. Chcihester; E. H. Seabury; S. J. Thompson; R. R. C. Clement

2011-10-01T23:59:59.000Z

430

Collisionally Induced Atomic Clock Shifts and Correlations  

E-Print Network (OSTI)

We develop a formalism to incorporate exchange symmetry considerations into the calculation of collisional frequency shifts and blackbody radiation effects for atomic clock transitions using a density matrix formalism. The formalism is developed for both fermionic and bosonic atomic clocks. Results for a finite temperature ${}^{87}$Sr ${}^1S_0$ ($F = 9/2$) atomic clock in a magic wavelength optical lattice are presented.

Y. B. Band; I. Osherov

2010-11-15T23:59:59.000Z

431

Use of depleted uranium metal as cask shielding in high-level waste storage, transport, and disposal systems  

SciTech Connect

The US DOE has amassed over 555,000 metric tons of depleted uranium from its uranium enrichment operations. Rather than dispose of this depleted uranium as waste, this study explores a beneficial use of depleted uranium as metal shielding in casks designed to contain canisters of vitrified high-level waste. Two high-level waste storage, transport, and disposal shielded cask systems are analyzed. The first system employs a shielded storage and disposal cask having a separate reusable transportation overpack. The second system employs a shielded combined storage, transport, and disposal cask. Conceptual cask designs that hold 1, 3, 4 and 7 high-level waste canisters are described for both systems. In all cases, cask design feasibility was established and analyses indicate that these casks meet applicable thermal, structural, shielding, and contact-handled requirements. Depleted uranium metal casting, fabrication, environmental, and radiation compatibility considerations are discussed and found to pose no serious implementation problems. About one-fourth of the depleted uranium inventory would be used to produce the casks required to store and dispose of the nearly 15,400 high-level waste canisters that would be produced. This study estimates the total-system cost for the preferred 7-canister storage and disposal configuration having a separate transportation overpack would be $6.3 billion. When credits are taken for depleted uranium disposal cost, a cost that would be avoided if depleted uranium were used as cask shielding material rather than disposed of as waste, total system net costs are between $3.8 billion and $5.5 billion.

Yoshimura, H.R.; Ludwigsen, J.S.; McAllaster, M.E. [and others

1996-09-01T23:59:59.000Z

432

A 2-D Test Problem for CFD Modeling Heat Transfer in Spent Fuel Transfer Cask Neutron Shields  

SciTech Connect

In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 5-10 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper presents results for a simple 2-D problem that is an effective numerical analog for the neutron shield application. Because it is 2-D, solutions can be obtained relatively quickly allowing a comparison and assessment of sensitivity to model parameter changes. Turbulence models are considered as well as the tradeoff between steady state and transient solutions. Solutions are compared for two commercial CFD codes, FLUENT and STAR-CCM+. The results can be used to provide input to the CFD Best Practices for this application. Following study results for the 2-D test problem, a comparison of simulation results is provided for a high Rayleigh number experiment with large annular gap. Because the geometry of this validation is significantly different from the neutron shield, and due to the critical nature of this application, the argument is made for new experiments at representative scales

Zigh, Ghani; Solis, Jorge; Fort, James A.

2011-01-14T23:59:59.000Z

433

Chapter 2 Suggested Problems: Final Answer Key Atomic mass: mass of an individual atom  

E-Print Network (OSTI)

Chapter 2 Suggested Problems: Final Answer Key 2.1 Atomic mass: mass of an individual atom Atomic;Chapter 3 Suggested Problems: Final Answer Key 3.1 Atomic Structure: relates the # of protons and neutrons of intercepts 2 2 1 Reduction not necessary Enclosure (221) #12;Chapter 12 Suggested Problems: Final Answer Key

Grunlan, Melissa A.

434

General Atomics (GA) Fusion News: A New Spin on Understanding...  

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

General Atomics (GA) Fusion News: A New Spin on Understanding Plasma Confinement American Fusion News Category: General Atomics (GA) Link: General Atomics (GA) Fusion News: A New...

435

Pages that link to "Atomic City, Idaho" | Open Energy Information  

Open Energy Info (EERE)

Share this page on Facebook icon Twitter icon Pages that link to "Atomic City, Idaho" Atomic City, Idaho Jump to: navigation, search What links here Page: Atomic City,...

436

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

437

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)
438

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

439

Precision spectroscopy of the helium atom.  

SciTech Connect

Persistent efforts in both theory and experiment have yielded increasingly precise understanding of the helium atom. Because of its simplicity, the helium atom has long been a testing ground for relativistic and quantum electrodynamic effects in few-body atomic systems theoretically and experimentally. Comparison between theory and experiment of the helium spectroscopy in 1s2p{sup 3}P{sub J} can potentially extract a very precise value of the fine structure constant a. The helium atom can also be used to explore exotic nuclear structures. In this paper, we provide a brief review of the recent advances in precision calculations and measurements of the helium atom.

Hu, S.-M.; Lu, Z.-T.; Yan, Z.-C.; Physics; Univ. of Science and Technology of China; Univ. of Chicago; Univ. of New Brunswick

2009-06-01T23:59:59.000Z

440

Test of the quantumness of atom-atom correlations in a bosonic gas  

E-Print Network (OSTI)

It is shown how the quantumness of atom-atom correlations in a trapped bosonic gas can be made observable. Application of continuous feedback control of the center of mass of the atomic cloud is shown to generate oscillations of the spatial extension of the cloud, whose amplitude can be directly used as a characterization of atom-atom correlations. Feedback parameters can be chosen such that the violation of a Schwarz inequality for atom-atom correlations can be tested at noise levels much higher than the standard quantum limit.

D. Ivanov; S. Wallentowitz

2006-03-16T23:59:59.000Z

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

DEMONSTRATION OF THE GLYCOLIC-FORMIC FLOWSHEET IN THE SRNL SHIELDED CELLS USING ACTUAL WASTE  

SciTech Connect

Glycolic acid was effective at dissolving many metals, including iron, during processing with simulants. Criticality constraints take credit for the insolubility of iron during processing to prevent criticality of fissile materials. Testing with actual waste was needed to determine the extent of iron and fissile isotope dissolution during Chemical Process Cell (CPC) processing. The Alternate Reductant Project was initiated by the Savannah River Remediation (SRR) Company to explore options for the replacement of the nitric-formic flowsheet used for the CPC at the Defense Waste Processing Facility (DWPF). The goals of the Alternate Reductant Project are to reduce CPC cycle time, increase mass throughput of the facility, and reduce operational hazards. In order to achieve these goals, several different reductants were considered during initial evaluations conducted by Savannah River National Laboratory (SRNL). After review of the reductants by SRR, SRNL, and Energy Solutions (ES) Vitreous State Laboratory (VSL), two flowsheets were further developed in parallel. The two flowsheet options included a nitric-formic-glycolic flowsheet, and a nitric-formic-sugar flowsheet. As of July 2011, SRNL and ES/VSL have completed the initial flowsheet development work for the nitric-formic-glycolic flowsheet and nitric-formic-sugar flowsheet, respectively. On July 12th and July 13th, SRR conducted a Systems Engineering Evaluation (SEE) to down select the alternate reductant flowsheet. The SEE team selected the Formic-Glycolic Flowsheet for further development. Two risks were identified in SEE for expedited research. The first risk is related to iron and plutonium solubility during the CPC process with respect to criticality. Currently, DWPF credits iron as a poison for the fissile components of the sludge. Due to the high iron solubility observed during the flowsheet demonstrations with simulants, it was necessary to determine if the plutonium in the radioactive sludge slurry demonstrated the same behavior. The second risk is related to potential downstream impacts of glycolate on Tank Farm processes. The downstream impacts will be evaluated by a separate research team. Waste Solidification Engineering (WSE) has requested a radioactive demonstration of the Glycolic-Formic Flowsheet with radioactive sludge slurry be completed in the Shielded Cells Facility of the SRNL. The Shielded Cells demonstration only included a Sludge Receipt and Adjustment Tank (SRAT) cycle, and not a Slurry Mix Evaporator (SME) cycle or the co-processing of salt products. Sludge Batch 5 (SB5) slurry was used for the demonstration since it was readily available, had been previously characterized, and was generally representative of sludges being processing in DWPF. This sample was never used in the planned Shielded Cells Run 7 (SC-7).

Lambert, D.; Pareizs, J.; Click, D.

2011-11-07T23:59:59.000Z

442

Monitoring atom-atom entanglement and decoherence in a solvable tripartite open system in cavity QED  

E-Print Network (OSTI)

We solve exactly the dynamics of two strongly-driven two-level atoms resonantly coupled to a dissipative cavity field mode. Starting with the cavity field vacuum state, we show that the entanglement of the atom-atom subsystem cannot be created or increased. On the other hand, when the atoms are initially entangled the atomic Hilbert space divides into two subspaces. One of them is decoherence free so that the initial atomic entanglement remains available for applications, even in presence of a low enough atomic decay rate. In the other subspace a measure of entanglement, decoherence, and also purity, are described by a similar functional behavior that can be monitored by joint atomic measurements. Furthermore, we show the possible generation of Schr\\"odinger-cat-like states for the whole system in the transient regime, as well as of entanglement for the cavity field and the atom-atom subsystems conditioned by measurements on the complementary subsystem.

Bina, Matteo; Lulli, Alfredo; Solano, Enrique

2007-01-01T23:59:59.000Z

443

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.

444

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

2004-11-16T23:59:59.000Z

445

Shielding analysis of the TRUPACT-series casks for transportation of Hanford HLW  

SciTech Connect

In this paper, the authors propose the possibility of utilizing the TRUPACT-series casks for the transportation of high-level waste (HLW) from the Hanford reservation. The configurations of the TRUPACT series are a rectangular parallelepiped and a right circular cylinder, which are the TRUPACT-1 and -11, respectively. The TRUPACT series was designed as a type B contact-handled transuranic (CH-TRU) waste transportation system for use in Waste Isolation Pilot Plant-related operations and was subjected to type B container accident tests, which it successfully passed. Thus from a safety standpoint, the TRUPACT series is provided with double containment, impact limitation, and fire-retardant capabilities. However, the shielding analysis has shown the major modifications are required to allow for the transport of even a reasonable fraction of Hanford HLW.

Banjac, V.; Sanchez, P.E.; Hills, C.R.; Heger, A.S. (Univ. of New Mexico, Albuquerque, NM (United States))

1993-01-01T23:59:59.000Z

446

Thermal insulating barrier and neutron shield providing integrated protection for a nuclear reactor vessel  

DOE Patents (OSTI)

The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel to form a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive valving also includes bistable vents at the upper end of the thermal insulating barrier for releasing steam. A removable, modular neutron shield extending around the upper end of the reactor cavity below the nozzles forms with the upwardly and outwardly tapered transition on the outer surface of the reactor vessel, a labyrinthine channel which reduces neutron streaming while providing a passage for the escape of steam during a severe accident, and for the cooling air which is circulated along the reactor cavity walls outside the thermal insulating barrier during normal operation of the reactor.

Schreiber, Roger B. (Penn Twp., PA); Fero, Arnold H. (New Kensington, PA); Sejvar, James (Murrysville, PA)

1997-01-01T23:59:59.000Z

447

Active detection of shielded SNM with 60-keV neutrons  

Science Conference Proceedings (OSTI)

Fissile materials, e.g. {sup 235}U and {sup 239}Pu, can be detected non-invasively by active neutron interrogation. A unique characteristic of fissile material exposed to neutrons is the prompt emission of high-energy (fast) fission neutrons. One promising mode of operation subjects the object to a beam of medium-energy (epithermal) neutrons, generated by a proton beam impinging on a Li target. The emergence of fast secondary neutrons then clearly indicates the presence of fissile material. Our interrogation system comprises a low-dose 60-keV neutron generator (5 x 10{sup 6}/s), and a 1 m{sup 2} array of scintillators for fast neutron detection. Preliminary experimental results demonstrate the detectability of small quantities (370 g) of HEU shielded by steel (200 g/cm{sup 2}) or plywood (30 g/cm{sup 2}), with a typical measurement time of 1 min.

Hagmann, C; Dietrich, D; Hall, J; Kerr, P; Nakae, L; Newby, R; Rowland, M; Snyderman, N; Stoeffl, W

2008-07-08T23:59:59.000Z

448

Thermal insulating barrier and neutron shield providing integrated protection for a nuclear reactor vessel  

DOE Patents (OSTI)

The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel to form a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive valving also includes bistable vents at the upper end of the thermal insulating barrier for releasing steam. A removable, modular neutron shield extending around the upper end of the reactor cavity below the nozzles forms with the upwardly and outwardly tapered transition on the outer surface of the reactor vessel, a labyrinthine channel which reduces neutron streaming while providing a passage for the escape of steam during a severe accident, and for the cooling air which is circulated along the reactor cavity walls outside the thermal insulating barrier during normal operation of the reactor. 8 figs.

Schreiber, R.B.; Fero, A.H.; Sejvar, J.

1997-12-16T23:59:59.000Z

449

The Linac Coherent Light Source at SLAC. Radiological Considerations and Shielding calculations  

Science Conference Proceedings (OSTI)

The Linac Coherent Light Source (LCLS) at SLAC will be the world's first X-ray free electron laser when it becomes operational in 2009. Pulses of X-ray laser light from LCLS will be many orders of magnitude brighter and several orders of magnitude shorter than what can be produced by other X-ray sources available in the world. These characteristics will enable frontier new science in many areas. This paper describes the LCLS beam parameters and its lay-out. Results of the Monte Carlo calculations for the shielding design of the electron dump line, radiation damage to undulator, the residual radiation and the soil activation around the electron dump are presented.

Mao, X.S.; Fasso, A.; Nakao, N.; Rokni, S.H.; Vincke, H.; /SLAC

2005-12-02T23:59:59.000Z

450

Formation of negative hydrogen ion: Polarization electron capture and nonthermal shielding  

Science Conference Proceedings (OSTI)

The influence of the nonthermal shielding on the formation of the negative hydrogen ion (H{sup -}) by the polarization electron capture are investigated in partially ionized generalized Lorentzian plasmas. The Bohr-Lindhard method has been applied to obtain the negative hydrogen formation radius and cross section as functions of the collision energy, de Broglie wave length, Debye length, impact parameter, and spectral index of the plasma. The result shows that the nonthermal character of the plasma enhances the formation radius of the negative hydrogen, especially, for small Debye radii. It is found that the nonthermal effect increases the formation cross section of the negative hydrogen. It is also found that the maximum position of the formation cross section approaches to the collision center with an increase of the spectral index. In addition, it is found that the formation cross section significantly decreases with an increase of the Debye length, especially, for small spectral indices.

Ki, Dae-Han [Department of Applied Physics, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of); Jung, Young-Dae [Department of Applied Physics, Hanyang University, Ansan, Kyunggi-Do 426-791 (Korea, Republic of); Department of Bio-Nano Technology, 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)

2012-09-07T23:59:59.000Z

451

Magnetic-field shielding of satellites from high-energy-electron environments  

Science Conference Proceedings (OSTI)

Magnet configurations are found that limit the 6-MeV electrons threatening satellite electronics to <1% of the incident flux. Successful configurations of permanent magnets and electromagnets require magnetic energies of {approximately}8 to 12 kJ to protect each liter of electronics volume. The fundamental strength of materials leads to a required minimum mass of {approximately}48 to 64 kg/liter to support the magnetic pressure. With the electronics requiring {approximately}5 liters, several hundred kilograms are needed for this support. Except for protecting small apertures, magnetic shielding provides little, if any, advantage over that obtained by coating with an equivalent mass using traditional methods. 7 refs., 9 figs., 1 tab.

Vittitoe, C.N.

1990-05-01T23:59:59.000Z

452

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

Science Conference Proceedings (OSTI)

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

453

Role of crack tip shielding in the initiation and growth of long and small fatigue cracks in composite microstructures  

Science Conference Proceedings (OSTI)

The role of crack tip shielding in retarding the initiation and growth of fatigue cracks has been examined in metallic composite microstructures (consisting of hard and soft phases), with the objective of achieving maximum resistance to fatigue. Specifically, duplex ferritic-martensitic structures have been developed in AISI 1008 and 1015 mild steels to promote shielding without loss in strength. The shielding is developed primarily from crack deflection and resultant crack closure, such that unusually high long crack propagation resistance is obtained. It is found that the fatigue threshold ..delta..K/sub TH/ in AISI 1008 can be increased by more than 100 pct to over 20 MPa ..sqrt..m, without sacrifice in strength, representing the highest ambient temperature threshold reported for a metallic alloy to date. Similar but smaller increases are found in AISI 1015. The effect of the dual-phase microstructures on crack initiation and small crack (10 to 1000 ..mu..m) growth, however, is markedly different, characteristic of behavior influenced by the mutual competition of intrinsic and extrinsic (shielding) ''toughening'' mechanisms. Accordingly, the composite microstructures which appear to show the highest resistance to the growth of long cracks, show the lowest resistance to crack initiation and small crack growth. In general, dual-phase steels are found to display remarkable fatigue properties, with fatigue limits as high as 58 pct of the tensile strengths and fatigue thresholds in the range of 13 to 20 MPa..sqrt..m.

Shang, J.K.; Tzou, J.L.; Ritchie, R.O. (Materials and Chemical Sciences Div., Lawrence Berkeley Lab., and Dept. of Materials Science and Mineral Engineering, Univ. of California, Berkeley, CA (US))

1987-09-01T23:59:59.000Z

454

Proof-of-Concept Assessment of a Photofission-Based Interrogation System for the Detection of Shielded Nuclear Material  

SciTech Connect

A photonuclear interrogation method was experimentally assessed for the detection of shielded nuclear materials. Proof-of-Concept assessment was performed at the Los Alamos National Laboratory (LANL) TA-18 facility and used the INEEL VARITRON electron accelerator. Experiments were performed to assess and characterize the delayed neutron emission responses for different nuclear materials with various shield configurations using three ''nominal'' electron beam energies; 8-, 10-, and 11-MeV. With the exception of highly enriched uranium (HEU), the nuclear materials assessed represent material types commonly encountered in commerce. The specific nuclear materials studied include a solid 4.8-kg HEU sphere, a 5-kg multiple-object, depleted uranium (DU) [uranium with about 0.2% enrichment with U-235] target, and two 11-kg thorium disks. The shield materials selected include polyethylene, borated-polyethylene, and lead. Experimental results, supported with numerical predictions, have shown that the photonuclear interrogation technique is quite capable of detecting shielded nuclear material via the direct measurement of the photofission-induced delayed neutron emissions. To identify or discriminate between nuclear material types (i.e., depleted uranium, HEU, and thorium), a ratio of delayed neutron counts at two different beam energies is utilized. This latter method, referred to as the dual-beam energy ratio Figure-of-Merit, allows one to differentiate among the three nuclear material types.

Jones, J. L.; Yoon, W. Y.; Harker, Y. D.; Hoggan, J. M.; Haskell, K. J.; VanAusdeln, L. A.

2000-11-01T23:59:59.000Z

455

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

Science Conference Proceedings (OSTI)

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

456

Pulse-echo ultrasonic inspection system for in-situ nondestructive inspection of Space Shuttle RCC heat shields.  

SciTech Connect

The reinforced carbon-carbon (RCC) heat shield components on the Space Shuttle's wings must withstand harsh atmospheric reentry environments where the wing leading edge can reach temperatures of 3,000 F. Potential damage includes impact damage, micro cracks, oxidation in the silicon carbide-to-carbon-carbon layers, and interlaminar disbonds. Since accumulated damage in the thick, carbon-carbon and silicon-carbide layers of the heat shields can lead to catastrophic failure of the Shuttle's heat protection system, it was essential for NASA to institute an accurate health monitoring program. NASA's goal was to obtain turnkey inspection systems that could certify the integrity of the Shuttle heat shields prior to each mission. Because of the possibility of damaging the heat shields during removal, the NDI devices must be deployed without removing the leading edge panels from the wing. Recently, NASA selected a multi-method approach for inspecting the wing leading edge which includes eddy current, thermography, and ultrasonics. The complementary superposition of these three inspection techniques produces a rigorous Orbiter certification process that can reliably detect the array of flaws expected in the Shuttle's heat shields. Sandia Labs produced an in-situ ultrasonic inspection method while NASA Langley developed the eddy current and thermographic techniques. An extensive validation process, including blind inspections monitored by NASA officials, demonstrated the ability of these inspection systems to meet the accuracy, sensitivity, and reliability requirements. This report presents the ultrasonic NDI development process and the final hardware configuration. The work included the use of flight hardware and scrap heat shield panels to discover and overcome the obstacles associated with damage detection in the RCC material. Optimum combinations of custom ultrasonic probes and data analyses were merged with the inspection procedures needed to properly survey the heat shield panels. System features were introduced to minimize the potential for human factors errors in identifying and locating the flaws. The in-situ NDI team completed the transfer of this technology to NASA and USA employees so that they can complete 'Return-to-Flight' certification inspections on all Shuttle Orbiters prior to each launch.

Roach, Dennis Patrick; Walkington, Phillip D.; Rackow, Kirk A.

2005-06-01T23:59:59.000Z

457

Benchmark Experiment of Neutron Penetration Through Iron and Concrete Shields for Hundreds-of-MeV Quasi-Monoenergetic Neutrons - I: Measurements of Neutron Spectrum by a Multimoderator Spectrometer  

Science Conference Proceedings (OSTI)

Neutron Measurements / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

H. Yashima; H. Iwase; M. Hagiwara; Y. Kirihara; S. Taniguchi; H. Yamakawa; K. Oishi; Y. Iwamoto; D. Satoh; Y. Nakane; H. Nakashima; T. Itoga; N. Nakao; T. Nakamura; A. Tamii; K. Hatanaka

458

Benchmark Experiment of Neutron Penetration Through Iron and Concrete Shields for Hundreds-of-MeV Quasi-Monoenergetic Neutrons - II: Measurements of Neutron Spectrum by an Organic Liquid Scintillator  

Science Conference Proceedings (OSTI)

Neutron Measurements / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 2) / Radiation Protection

M. Hagiwara; H. Iwase; Y. Kirihara; H. Yashima; Y. Iwamoto; D. Satoh; Y. Nakane; H. Nakashima; T. Nakamura; A. Tamii; K. Hatanaka

459

Monitoring atom-atom entanglement and decoherence in a solvable tripartite open system in cavity QED  

E-Print Network (OSTI)

We present a fully analytical solution of the dynamics of two strongly-driven atoms resonantly coupled to a dissipative cavity field mode. We show that an initial atom-atom entanglement cannot be increased. In fact, the atomic Hilbert space divides into two subspaces, one of which is decoherence free so that the initial atomic entanglement remains available for applications, even in presence of a low enough atomic decay rate. In the other subspace a measure of entanglement, decoherence, and also purity, are described by a similar functional behavior that can be monitored by joint atomic measurements. Furthermore, we show the possible generation of Schr\\"odinger-cat-like states for the whole system in the transient regime, as well as of entanglement for the cavity field and the atom-atom subsystems conditioned by measurements on the complementary subsystem.

Matteo Bina; Federico Casagrande; Alfredo Lulli; Enrique Solano

2007-11-08T23:59:59.000Z

460

CTrigger: Exposing Atomicity Violation Bugs from Their Hiding Places  

E-Print Network (OSTI)

of the two molecules, broken down by atom, helps the user to understand which atoms of the drug and protein

Lu, Shan

Note: This page contains sample records for the topic "atomic shield 1947-1952" 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

Hyperbaric hydrothermal atomic force microscope  

SciTech Connect

A hyperbaric hydrothermal atomic force microscope (AFM) is provided to image solid surfaces in fluids, either liquid or gas, at pressures greater than normal atmospheric pressure. The sample can be heated and its surface imaged in aqueous solution at temperatures greater than 100.degree. C. with less than 1 nm vertical resolution. A gas pressurized microscope base chamber houses the stepper motor and piezoelectric scanner. A chemically inert, flexible membrane separates this base chamber from the sample cell environment and constrains a high temperature, pressurized liquid or gas in the sample cell while allowing movement of the scanner. The sample cell is designed for continuous flow of liquid or gas through the sample environment.

Knauss, Kevin G. (Livermore, CA); Boro, Carl O. (Milpitas, CA); Higgins, Steven R. (Laramie, WY); Eggleston, Carrick M. (Laramie, WY)

2002-01-01T23:59:59.000Z

462

Atomic force microscope: Enhanced sensitivity  

SciTech Connect

Atomic force microscopes (AFMs) are a recent development representing the state of the art in measuring ultrafine surface features. Applications are found in such fields of research as biology, microfabrication, material studies, and surface chemistry. Fiber-optic interferometer techniques developed at LLNL offer the potential of improving the vertical resolution of these instruments by up to 2 orders of magnitude. We are attempting to replace the current AFM measurement scheme, which consists of an optical beam deflection approach, with our fiber-optic interferometer scheme, a much more sensitive displacement measurement technique. In performing this research, we hope to accomplish two important goals; (1) to enhance the sensitivity of the AFM, and (2) to achieve important improvements in our fiber-optic interferometer technology.

Davis, D.T.

1995-06-01T23:59:59.000Z

463

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

464

Cavity cooling of a single atom  

E-Print Network (OSTI)

All conventional methods to laser-cool atoms rely on repeated cycles of optical pumping and spontaneous emission of a photon by the atom. Spontaneous emission in a random direction is the dissipative mechanism required to remove entropy from the atom. However, alternative cooling methods have been proposed for a single atom strongly coupled to a high-finesse cavity; the role of spontaneous emission is replaced by the escape of a photon from the cavity. Application of such cooling schemes would improve the performance of atom cavity systems for quantum information processing. Furthermore, as cavity cooling does not rely on spontaneous emission, it can be applied to systems that cannot be laser-cooled by conventional methods; these include molecules (which do not have a closed transition) and collective excitations of Bose condensates, which are destroyed by randomly directed recoil kicks. Here we demonstrate cavity cooling of single rubidium atoms stored in an intracavity dipole trap. The cooling mechanism res...

Maunz, P; Schuster, I; Syassen, N; Pinkse, P W H; Rempe, G

2004-01-01T23:59:59.000Z

465

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.

466

Theory of atomic motion in resonant radiation  

SciTech Connect

Atomic motion in resonant and near resonant electromagnetic radiation is investigated theoretically. The exposition begins with a study of atomic motion in a resonant standing light wave, with a view toward isotope separation by selective photodeflection, and proceeds to the investigation of more general problems of atomic motion in resonant radiation. The body of the work consists of six chapters, each of which was prepared as a manuscript for publication in the open literature.

Cook, R.J.

1980-03-01T23:59:59.000Z

467

Method for enhanced atomization of liquids  

DOE Patents (OSTI)

In a process for atomizing a slurry or liquid process stream in which a slurry or liquid is passed through a nozzle to provide a primary atomized process stream, an improvement which comprises subjecting the liquid or slurry process stream to microwave energy as the liquid or slurry process stream exits the nozzle, wherein sufficient microwave heating is provided to flash vaporize the primary atomized process stream.

Thompson, Richard E. (27121 Puerta del Oro, Mission Viejo, CA 92691); White, Jerome R. (44755 Wyandotte, Hemet, CA 92544)

1993-01-01T23:59:59.000Z

468

NIST Handbook of Basic Atomic Spectroscopic Data  

Science Conference Proceedings (OSTI)

... The compilation includes data for the neutral and singly-ionized atoms of all elements hydrogen through einsteinium (Z = 1-99). ... Access the Data. ...

2011-12-09T23:59:59.000Z

469

NIST Atomic Form Factors: Concerns with standard ...  

Science Conference Proceedings (OSTI)

... pair production cross-section in the nuclear field (? n ... upon angle (in f 0 ) and energy (in f ... All general theories make the isolated atom approximation ...

470

Atom Manipulation with the Scanning Tunneling Microscope  

Science Conference Proceedings (OSTI)

... nanostructure from an unknown random collection of atoms without human intervention. ... a set of extensible rules, and allows for error correction. ...

2013-04-26T23:59:59.000Z

471

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. 

472

Atom Probe Tomography and Transmission Electron Microscopy ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Atom probe tomography (APT) and analytical transmission .... of a Leaking Type 316 Socket Weld in a Boron Injection Tank Sampling Line.

473

Quantization of Atomic and Nuclear Rest Masses  

E-Print Network (OSTI)

We were able to quantize phenomenologically the first time the atomic and nuclear rest masses. Note that this quantization rule is justified for atoms and nuclei with different