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Reducing the Detection Limit for Tetraphenylborate in Tank 50H Waste (open access)

Reducing the Detection Limit for Tetraphenylborate in Tank 50H Waste

SRTC personnel are developing a technique that can determine the concentration of tetraphenylborate (TPB) at 300 grams in 100,000 gallons of salt solution (0.8 mg/L) in the presence of0.378 Ci/gal of Cs-137. The current High Performance Liquid Chromatography (HPLC) method of analysis can determine the TPB concentration at 5 mg/L and higher. The limit of quantitation was lowered by modification of the sample preparation steps. The HPLC sample preparation method currently used requires neutralization of the tank waste sample followed by extraction with acetonitrile. This method dilutes the tank waste sample 6.5 to 1 increasing the limit of quantitation. The method described in this report concentrates the sample two-fold lowering the limit of quantitation from 5 mg/L to 0.25mg/L. Researchers used solvent extraction of undiluted tank waste to isolate, and concentrate (two-fold) samples of tank supernate and Plant Inhibited Water (PIW) that simulated tank supernate at the cesium level of approximately 0.3 Ci/gal. The 137Cs content in the tank supernate measured 0.65 Ci/gal prior to a two-fold dilution with PIW. The concentration of the TPB was determined by HPLC on a reversed-phase HPLC column using methanol, acetonitrile, and buffered water as the mobile phase. Important Findings: The 0.8 mg/L quantitation …
Date: July 14, 2004
Creator: White, Thomas L.
Object Type: Report
System: The UNT Digital Library
Rising Energy Competition and Energy Security in Northeast Asia: Issues for U.S. Policy (open access)

Rising Energy Competition and Energy Security in Northeast Asia: Issues for U.S. Policy

None
Date: July 14, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 257, Ed. 1 Wednesday, July 14, 2004 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 257, Ed. 1 Wednesday, July 14, 2004

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: July 14, 2004
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Stromal-epithelial interactions in aging and cancer: Senescent fibroblasts alter epithelial cell differentiation (open access)

Stromal-epithelial interactions in aging and cancer: Senescent fibroblasts alter epithelial cell differentiation

Cellular senescence suppresses cancer by arresting cells at risk for malignant tumorigenesis. However, senescent cells also secrete molecules that can stimulate premalignant cells to proliferate and form tumors, suggesting the senescence response is antagonistically pleiotropic. We show that premalignant mammary epithelial cells exposed to senescent human fibroblasts in mice irreversibly lose differentiated properties, become invasive and undergo full malignant transformation. Moreover, using cultured mouse or human fibroblasts and non-malignant breast epithelial cells, we show that senescent fibroblasts disrupt epithelial alveolar morphogenesis, functional differentiation, and branching morphogenesis. Further, we identify MMP-3 as the major factor responsible for the effects of senescent fibroblasts on branching morphogenesis. Our findings support the idea that senescent cells contribute to age-related pathology, including cancer, and describe a new property of senescent fibroblasts--the ability to alter epithelial differentiation--that might also explain the loss of tissue function and organization that is a hallmark of aging.
Date: July 14, 2004
Creator: Parrinello, Simona; Coppe, Jean-Philippe; Krtolica, Ana & Campisi, Judith
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0217 (open access)

Texas Attorney General Opinion: GA-0217

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification; Whether article XI, section 11(A) of the Texas Constitution applies to city officers with two year terms or city police officers, and whether a home-rule city with two year terms may provide in its charter that a mayor or council member who becomes a candidate for another office automatically vacates the current office (RQ-0168-GA)
Date: July 14, 2004
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Věstník (Temple, Tex.), Vol. 92, No. 27, Ed. 1 Wednesday, July 14, 2004 (open access)

Věstník (Temple, Tex.), Vol. 92, No. 27, Ed. 1 Wednesday, July 14, 2004

Weekly Czech and English language newspaper from Temple, Texas published as the official organ of the Slavonic Benevolent Order of the State of Texas that includes news of interest to members along with advertising.
Date: July 14, 2004
Creator: Vanicek, Brian
Object Type: Newspaper
System: The Portal to Texas History
X-Ray Laser Induced Photoelectron Spectroscopy for Single-State Measurements (open access)

X-Ray Laser Induced Photoelectron Spectroscopy for Single-State Measurements

We demonstrate single-shot x-ray laser induced time-of-flight photoelectron spectroscopy on metal and semiconductor surfaces with picosecond time resolution. The LLNL COMET compact tabletop x-ray laser source provides the necessary high photon flux (>10{sup 12}/pulse), monochromaticity, picosecond pulse duration, and coherence for probing ultrafast changes in the chemical and electronic structure of these materials. Static valence band and shallow core-level photoemission spectra are presented for ambient temperature polycrystalline Cu foils and Ge(100). Surface contamination was removed by UV ozone cleaning prior to analysis. The ultrafast nature of this technique lends itself to true single-state measurements of shocked and heated materials.
Date: July 14, 2004
Creator: Nelson, A J; Dunn, J; van Buuren, T & Hunter, J
Object Type: Article
System: The UNT Digital Library