Scintillating Glass Fiber-Optic Neutron Sensors

ABSTRACTPacific Northwest Laboratory (PNL) has fabricated cerium-activated lithium silicate scintillating fibers via a hot-downdraw process. These fibers, which, as produced, typically have a transmission length (e−1 length) of greater than 2 meters, are found to undergo aging when subjected to room air. The aging, which is complete in a few weeks, reduces the transmission length to the order of 0.5 meter. Because of the high alkali content of the glass (on the order of 20-30 mole % lithia), we have attributed this aging to aqueous corrosion at the polymer cladding/glass interface. Changes in transmission with chemical treatment of the surface support the corrosion model. Fiber transmission performance has been preserved by modifying the hot-downdraw to a double crucible to produce glass-on-glass waveguides.

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Aqueous Corrosion of the French LWR Solution Reference Glass First Generation Model

MRS Proceedings ◽

10.1557/proc-112-703 ◽

1987 ◽

Vol 112 ◽

Cited By ~ 3

Author(s):

E. Mouche ◽

Vernaz E.

Keyword(s):

First Generation ◽

Generation Model ◽

Order Kinetic ◽

Aqueous Corrosion ◽

Interstitial Solution ◽

Silica Concentration ◽

Glass Interface ◽

Advanced Model ◽

And Diffusion ◽

Theoretical Results

AbstractExperiments have been performed on the aqueous dissolution of French LWR solution reference glass that have identified key dissolution mechanisms to be considered in modeling. The physical hypotheses on which the model relies are a dissolution rate governed by the silica concentration in solution according to a first order kinetic law, congruent release of the mobile elements at the gel-glass interface, and diffusion of silicic acid in the gel interstitial solution. A comparison of theoretical results obtained by a semi-analytical solution to the model and experimental results suggests some modifications to develop a more advanced model.

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C. gattii Emerges in Pacific Northwest, Kills Four

Family Practice News ◽

10.1016/s0300-7073(08)71430-0 ◽

2008 ◽

Vol 38 (23) ◽

pp. 22

Author(s):

DENISE NAPOLI

Keyword(s):

Pacific Northwest

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NUCLEAR SPIN-LATTICE RELAXATION IN A LITHIUM-SILICATE GLASS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1982927 ◽

1982 ◽

Vol 43 (C9) ◽

pp. C9-143-C9-147 ◽

Cited By ~ 4

Author(s):

P. Heitjans ◽

B. Bader ◽

K. Dörr ◽

H. J. Stöckman ◽

G. Kiese ◽

...

Keyword(s):

Silicate Glass ◽

Nuclear Spin ◽

Lattice Relaxation ◽

Spin Lattice Relaxation ◽

Lithium Silicate ◽

Spin Lattice ◽

Nuclear Spin Lattice Relaxation ◽

Lithium Silicate Glass

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Native Seed Production Manual for the Pacific Northwest

Native Plants Journal ◽

10.3368/npj.17.2.134 ◽

2016 ◽

Vol 17 (2) ◽

pp. 134-135

Author(s):

Amy Bartow ◽

Keyword(s):

Pacific Northwest ◽

Seed Production ◽

Native Seed ◽

The Pacific

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Suitability of Natural Areas for Representing Ecological Change in the Pacific Northwest

Natural Areas Journal ◽

10.3375/043.039.0408 ◽

2019 ◽

Vol 39 (4) ◽

pp. 452

Author(s):

Margaret H. Massie ◽

Todd M. Wilson ◽

Anita T. Morzillo ◽

Emilie B. Henderson

Keyword(s):

Pacific Northwest ◽

Ecological Change ◽

Natural Areas ◽

The Pacific

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Mcc Corrosion Tests at Reference Testing Conditions for A27 Cast steel in Hanford Ground Water

MRS Proceedings ◽

10.1557/proc-84-215 ◽

1986 ◽

Vol 84 ◽

Author(s):

M.D. Merz ◽

F. Gerber ◽

R. Wang

Keyword(s):

Pacific Northwest ◽

Pressure Vessel ◽

Static Pressure ◽

Cast Steel ◽

Statistical Treatment ◽

Testing Conditions ◽

Corrosion Tests ◽

Corrosion Rates ◽

High Level Nuclear Waste ◽

High Level

AbstractThe Materials Characterization Center (MCC) at Pacific Northwest Lab- oratory is performing three kinds of corrosion tests for the Basalt Waste Isolation Project (BWIP) to establish the interlaboratory reproducibility and uncertainty of corrosion rates of container materials for high-level nuclear waste. The three types of corrosion tests were selected to address two distinct conditions that are expected in a repository constructed in basalt. An air/steam test is designed to address corrosion during the operational period and static pressure vessel and flowby tests are designed to address corrosion under conditions that bound the condi ring the post-closure period of the repository.The results of tests at reference testing conditions, which were defined to facilitate interlaboratory comparison of data, are presented. Data are reported for the BWIP/MCC-105.5 Air/Steam Test, BWIP/MCC-105.1 Static Pressure Vessel, and BWIP/MC-105.4 Flowby Test. In those cases where data are available from a second laboratory, a statistical analysis of interlaboratory results is reported and expected confidence intervals for mean corrosion rates are given. Other statistical treatment of data include analyses of the effects of vessel-to-vessel variations, test capsule variations for the flowby test, and oven-to-oven variations for air/steam tests.

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