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All sources NASA NTRS DOE OSTI

DOE OSTI2012

Report for Batch Leach Analyses on Sediments at 100-HR-3 Operable Unit, Boreholes C7620, C7621, C7622, C7623, C7626, C7627, C7628, C7629, C7630, and C7866

This is a revision to a previously released report. This revision contains additional analytical results for the sample with HEIS number B2H4X7. Between November 4, 2010 and October 26, 2011 sediment samples were received from 100-HR-3 Operable Unit for geochemical studies. The analyses for this project were performed at the 331 building located in the 300 Area of the Hanford Site. The analyses were performed according to Pacific Northwest National Laboratory (PNNL) approved procedures and/or nationally recognized test procedures. The data sets include the sample identification numbers, analytical results, estimated quantification limits (EQL), and quality control data. The preparatory and analytical quality control requirements, calibration requirements, acceptance criteria, and failure actions are defined in the on-line QA plan 'Conducting Analytical Work in Support of Regulatory Programs' (CAW). This QA plan implements the Hanford Analytical Services Quality Assurance Requirements Documents (HASQARD) for PNNL. Samples were received with a chain of custody (COC) and were analyzed according to the sample identification numbers supplied by the client. All Samples were refrigerated upon receipt until prepared for analysis. All samples were received with custody seals intact unless noted in the Case Narrative. Holding time is defined as the time from sample preparation to the time of analyses. The prescribed holding times were met for all analytes unless noted in the Case Narrative. All reported analytical results meet the requirements of the CAW or client specified SOW unless noted in the case narrative. Due to the requirements of the statement of work and sampling events in the field, the 28 day and the 48 hr requirements cannot be met. The statement of work requires samples to be selected at the completion of the borehole. It is not always possible to complete a borehole and have the samples shipped to the laboratory within the hold time requirements. Duplicate RPD for Uranium 238 (38.9%) was above the acceptance limit (35) in 1E05003-DUP1 for ICPMS-Tc-U-WE The sample result is less than 10 times the detection limits. Duplicate recoveries are not applicable to this analyte. Duplicate RPD for Silver 107 (68.2%) was above the acceptance limit (35) in 2C06004-DUP1 for ICPMS-RCRA-AE The sample result is less than 10 times the detection limits. Duplicate recoveries are not applicable to this analyte. Matrix Spike Recovery for Chromium, Hexavalent (48.8%) was outside acceptance limits (75-125) in 1E23001-MS1 for Hexavalent Chromium/Soil. Potential Matrix interference. Sample results associated with this batch are below the EQL. There should be no impact to the data as reported. Matrix Spike Recovery for Chromium, Hexavalent (50.2%) was outside acceptance limits (75-125) in 2B22010-MS1 for Hexavalent Chromium/Soil. Potential Matrix interference. Sample results associated with this batch are below the EQL. There should be no impact to the data as reported.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2015

An inductively heated hot cavity catcher laser ion source

An inductively heated hot cavity catcher has been constructed for the production of low-energy ion beams of exotic, neutron-deficient Ag isotopes. A proof-of-principle experiment has been realized by implanting primary {sup 107}Ag{sup 21+} ions from a heavy-ion cyclotron into a graphite catcher. A variable-thickness nickel foil was used to degrade the energy of the primary beam in order to mimic the implantation depth expected from the heavy-ion fusion-evaporation recoils of N = Z {sup 94}Ag. Following implantation, the silver atoms diffused out of the graphite and effused into the catcher cavity and transfer tube, where they were resonantly laser ionized using a three-step excitation and ionization scheme. Following mass separation, the ions were identified by scanning the frequency of the first resonant excitation step while recording the ion count rate. Ion release time profiles were measured for different implantation depths and cavity temperatures with the mean delay time varying from 10 to 600 ms. In addition, the diffusion coefficients for silver in graphite were measured for temperatures of 1470 K, 1630 K, and 1720 K, from which an activation energy of 3.2 ± 0.3 eV could be determined.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2017

Shell structure of {sup 107,109}Ag nuclei and spin–parities nuclei in which the 1{sub g9/2} orbit is being filled

Occupation numbers and energies of proton and neutron orbits in the isotopes {sup 107}Ag and {sup 109}Ag were obtained on the basis of data on nucleon-stripping and nucleon-pickup reactions. A special data-analysis method reducing systematic and statistical uncertainties was applied in relevant calculations. It is shown that, in this region, the spin–parity of nuclei is determined by shells, pairing, and polarization. The schemes of proton and neutron (sub)orbits were constructed. These schemes explain the ground-state spin–parities of N, Z = 39–49 nuclei.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2010

Intense few-cycle hard-UV-pulse-induced internal conversion processes

The internal conversion coefficient for bound-free electron transition of originally energetically forbidden internal conversion processes induced by intense, few-cycle UV laser pulse of Gaussian shape in the case of isomers {sup 107}Ag{sup m} (K shell, E3, 25.47 keV), {sup 90}Nb{sup m} (L{sub 2} shell, M2+E3, 2.3 keV), {sup 183}W{sup m1}(M{sub 5} shell, E2, 1.79 keV), {sup 183}W{sup m2} (N{sub 1} shell, E1, 548 eV), and {sup 188}Re{sup m} (M{sub 2} shell, M3+E4, 2.63 keV), and {sup 235}U{sup m} (O{sub 4} and O{sub 5} shells, E3, 73.5 eV) is determined numerically. Experimental conditions and possibilities of the laser-induced internal conversion process of {sup 183}W{sup m2} from the N{sub 1} shell are discussed in more detail.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2014

Distortion of ethyne on coordination to silver acetylide, C{sub 2}H{sub 2}⋅⋅⋅AgCCH, characterised by broadband rotational spectroscopy and ab initio calculations

The rotational spectra of six isotopologues of a complex of ethyne and silver acetylide, C{sub 2}H{sub 2}⋅⋅⋅AgCCH, are measured by both chirped-pulse and Fabry-Perot cavity versions of Fourier-transform microwave spectroscopy. The complex is generated through laser ablation of a silver target in the presence of a gas sample containing 1% C{sub 2}H{sub 2}, 1% SF{sub 6}, and 98% Ar undergoing supersonic expansion. Rotational, A{sub 0}, B{sub 0}, C{sub 0}, and centrifugal distortion Δ{sub J} and Δ{sub JK} constants are determined for all isotopologues of C{sub 2}H{sub 2}⋅⋅⋅AgCCH studied. The geometry is planar, C{sub 2v} and T-shaped in which the C{sub 2}H{sub 2} sub-unit comprises the bar of the “T” and binds to the metal atom through its π electrons. In the r{sub 0} geometry, the distance of the Ag atom from the centre of the triple bond in C{sub 2}H{sub 2} is 2.2104(10) Å. The r(HC≡CH) parameter representing the bond distance separating the two carbon atoms and the angle, ∠(CCH), each defined within the C{sub 2}H{sub 2} sub-unit, are determined to be 1.2200(24) Å and 186.0(5)°, respectively. This distortion of the linear geometry of C{sub 2}H{sub 2} involves the hydrogen atoms moving away from the silver atom within the complex. The results thus reveal that the geometry of C{sub 2}H{sub 2} changes measurably on coordination to AgCCH. A value of 59(4) N m{sup −1} is determined for the intermolecular force constant, k{sub σ}, confirming that the complex is significantly more strongly bound than hydrogen and halogen-bonded analogues. Ab initio calculations of the r{sub e} geometry at the CCSD(T)(F12{sup *})/ACVTZ level of theory are consistent with the experimental results. The spectra of the {sup 107}Ag{sup 13}C{sup 13}CH and {sup 109}Ag{sup 13}C{sup 13}CH isotopologues of free silver acetylide are also measured for the first time allowing the geometry of the AgCCH monomer to be examined in greater detail than previously.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2011

Simultaneous Modification of Bottom-Contact Electrode and Dielectric Surfaces for Organic Thin-Film Transistors Through Single-Component Spin-Cast Monolayers

An efficient process is developed by spin-coating a single-component, self-assembled monolayer (SAM) to simultaneously modify the bottom-contact electrode and dielectric surfaces of organic thin-film transistors (OTFTs). This efficient interface modification is achieved using n-alkyl phosphonic acid based SAMs to prime silver bottom-contacts and hafnium oxide (HfO{sub 2}) dielectrics in low-voltage OTFTs. Surface characterization using near edge X-ray absorption fine structure (NEXAFS) spectroscopy, X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), and spectroscopic ellipsometry suggest this process yields structurally well-defined phosphonate SAMs on both metal and oxide surfaces. Rational selection of the alkyl length of the SAM leads to greatly enhanced performance for both n-channel (C60) and p-channel (pentacene) based OTFTs. Specifically, SAMs of n-octylphos-phonic acid (OPA) provide both low-contact resistance at the bottom-contact electrodes and excellent interfacial properties for compact semiconductor grain growth with high carrier mobilities. OTFTs based on OPA modifi ed silver electrode/HfO{sub 2} dielectric bottom-contact structures can be operated using < 3V with low contact resistance (down to 700 Ohm-cm), low subthreshold swing (as low as 75 mV dec{sup -1}), high on/off current ratios of 107, and charge carrier mobilities as high as 4.6 and 0.8 cm{sup 2} V{sup -1} s{sup -1}, for C60 and pentacene, respectively. These results demonstrate that this is a simple and efficient process for improving the performance of bottom-contact OTFTs.

36 MATERIALS SCIENCE↗

DOE OSTI1988

Nuclear Safety [Vol. 29, No. 1, January-March 1988]

Nuclear Safety is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated. Table of Contents for this issue follows. THE CHERNOBYL ACCIDENT: 1 Core History and Nuclide Inventory of the Chernobyl Core at the Time of Accident by Gerald Kirchner and Cornelius C. Noack; GENERAL SAFETY CONSIDERATIONS: 6 Nonprescriptive Nuclear Safety Regulation: The Example of Loss of Offsite Power by M. W. Golay, V. P. Manno, and C. Vlahoplus, Jr., 20 Nuclear Power Safety Goals in Light of the Chernobyl Accident by C. Whipple and C. Starr; ACCIDENT ANALYSIS: 29 Containment Loads from Severe Accidents—U.S. Program by W. Kerr and M. K. Dey; PLANT SAFETY FEATURES: 36 Safety Characteristics of Modern High-Temperature Reactors: Focus on German Designs by W. Kröger, H. Nickel, and R. Schulten; ENVIRONMENTAL EFFECTS: 49 Radiation Hormesis and Nuclear Safety by C. C. Congdon; OPERATING EXPERIENCES: 58 Evaluation of Nonradiological Water Chemistry at Power Reactors by Harvey Zibulsky, James J. Kottan, Walter J. Pasciak, Mary Ann Castrogivanni, and Sujit Banerjee, 64 Reactor Shutdown Experience Compiled by J. W. Cletcher, 67 Operating U.S. Power Reactors Compiled by E. G. Silver; RECENT DEVELOPMENTS: 85 General Administrative Activities Compiled by E. G. Silver, 94 Reports, Standards, and Safety Guides by D. S. Queener, 100 Status of Power-Reactor Projects Undergoing Licensing Review Compiled by E. G. Silver, 103 Proposed Rule Changes as of Sept. 30, 1987; ANNOUNCEMENTS: 5 Northwestern University Short Course on Radiation Safety, 28 International Approach to Nuclear Safety (After Three-Mile Island and Chernobyl), 57 RPI Short Course on Modern Developments in Boiling Heat Transfer and Two-Phase Flow, 107 20th DOE/NRC Nuclear Air Cleaning Conference, 110 Third International Topical Meeting on Nuclear Power Plant Thermal Hydraulics and Operations, 108 The Authors, 111 Indexes to Nuclear Safety, Volume 28.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI1988

Nuclear Safety [Vol. 29, No. 1, January-March 1988]

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2017

Efficient Light Extraction of Organic Light-Emitting Diodes on a Fully Solution-Processed Flexible Substrate

A flexible, nanocomposite substrate for maximizing light outcoupling efficiencies of organic light-emitting diodes (OLEDs) is introduced. In depth investigation is performed on designing the integrated strategy based on considerations of surface conductivity, microcavity tuning, and internal light scattering. The resulting nanocomposite substrate consists of silver nanowires as the electrode and a high-index polymer layer and a light-scattering layer for light extraction. It is able to outcouple both the waveguide and the substrate modes, two modes accounting for significant losses in OLED device efficiency. With enhanced light outcoupling, white OLEDs subsequently fabricated on the nanocomposite substrates demonstrate performance metrics of 107 lm W -1 power efficiency and 49% external quantum efficiency at 1000 cd m -2 . Thus, the nanocomposite substrate is fabricated by solution processes at low temperatures for potentially low manufacturing cost.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2016

Capacity of ETS-10 supported carbon nanosorbent for removal of multicomponent from off-gas stream

Nuclear fission results in fission and activation products, some of which are volatile under the conditions of used nuclear fuel (UNF) reprocessing. Several volatile radionuclides are released into the atmosphere through offgas stream, which includes {sup 3}H, {sup 14}C, {sup 129}I and noble gases, Kr and Xe. {sup 129}I is a highly mobile and volatile contaminant. It has half-life period about 1.57 x 107 years that tends to bioaccumulate, concentrating in the thyroid glands and affecting bio-metabolism in humans. {sup 85}Kr is a chemically inert radioisotope with a half-life of 10.7 years that continuously accumulate in the environment. Control of emissions of these contaminants is necessary to comply with the stringent regulatory limits placed on their releases to protect human health and environment. Removal of these contaminants has been a challenge since the 1950's, and several methods including cryogenic distillation, fluorocarbon absorption, wet scrubbing, and adsorption have been employed. Currently, adsorption on porous solid sorbent shows the most promise results. Up to now, several sorbents such as silver impregnated mordenite, silver ETS-10, chalcogen based aerogels, and metal organic framework, MOFs have been developed for this purpose. Despite these advances, development of economical and highly active sorbents for complete removal and immobilization of volatile radioactive gases remains a key challenge in realizing advanced fuel cycles. Present research work is focused on the determination of the removal capacity of C'at'ETS-10 sorbent for a multicomponent (iodine and krypton) off-gas stream at ambient temperature. Our previously reported work showed that the 10 wt% C'at'ETS-10 sorbent was active for adsorption of krypton as well as iodine at ambient temperature and pressure. Therefore, 10 wt% C'at'ETS-10 sorbent was synthesized by wet-impregnation technique. The performance evaluation of the prepared nanosorbent was examined for the removal of iodine and krypton from the breakthrough curves obtained using bench scale experimental setup. ETS-10 supported carbon nanoparticles, C'at'ETS-10 nanosorbent was successfully synthesized by wet-impregnation technique. The 1/8 inch pelletized sorbent was used to minimize the pressure drop in adsorption column. The capacity of sorbent was found to be 0.143 mg g{sup -1} for krypton and 24.5 mg g{sup -1} for iodine. This experimental results indicates the C'at'ETS-10 is the effect sorbent for removal of multicomponent, krypton as well as iodine from the off-gas stream at ambient temperature. (authors)

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

DOE OSTI2023

Towards Automated and High-Throughput Quantitative Sizing and Isotopic Analysis of Nanoparticles via Single Particle-ICP-TOF-MS

The work described herein assesses the ability to characterize gold nanoparticles (Au NPs) of 50 and 100 nm, as well as 60 nm silver shelled gold core nanospheres (Au/Ag NPs), for their mass, respective size, and isotopic composition in an automated and unattended fashion. Here, an innovative autosampler was employed to mix and transport the blanks, standards, and samples into a high-efficiency single particle (SP) introduction system for subsequent analysis by inductively coupled plasma–time of flight–mass spectrometry (ICP-TOF-MS). Optimized NP transport efficiency into the ICP-TOF-MS was determined to be >80%. This combination, SP-ICP-TOF-MS, allowed for high-throughput sample analysis. Specifically, 50 total samples (including blanks/standards) were analyzed over 8 h, to provide an accurate characterization of the NPs. This methodology was implemented over the course of 5 days to assess its long-term reproducibility. Impressively, the in-run and day-to-day variation of sample transport is assessed to be 3.54 and 9.52% relative standard deviation (%RSD), respectively. The determination of Au NP size and concentration was of <5% relative difference from the certified values over these time periods. Isotopic characterization of the 107 Ag/ 109 Ag particles (n = 132,630) over the course of the measurements was determined to be 1.0788 ± 0.0030 with high accuracy (0.23% relative difference) when compared to the multi-collector–ICP-MS determination.

36 MATERIALS SCIENCE↗

DOE OSTI2025

Pivotal trial characteristics and types of endpoints used to support Food and Drug Administration rare disease drug approvals between 2013 and 2022

Background/aims Rare disease drug development faces unique challenges, such as genotypic and phenotypic heterogeneity within small patient populations and a lack of established outcome measures for conditions without previously successful drug development programs. These challenges complicate the process of selecting the appropriate trial endpoints and conducting clinical trials in rare diseases. In this descriptive study, we examined novel drug approvals for non-oncologic rare diseases by the U.S. Food and Drug Administration’s Center for Drug Evaluation and Research over the past decade and characterized key regulatory and trial design elements with a focus on the primary efficacy endpoint utilized as the basis of approval. Methods Using the Food and Drug Administration’s Data Analysis Search Host database, we identified novel new drug applications and biologics license applications with orphan drug designation that were approved between 2013 and 2022 for non-oncologic indications. From Food and Drug Administration review documents and other external databases, we examined characteristics of pivotal trials for the included drugs, such as therapeutic area, trial design, and type of primary efficacy endpoints. Differences in trial design elements associated with primary efficacy endpoint type were assessed such as randomization and blinding. Then, we summarized the primary efficacy endpoint types utilized in pivotal trials by therapeutic area, approval pathway, and whether the disease etiology is well defined. Results One hundred and seven drugs that met our inclusion criteria were approved between 2013 and 2022. Assessment of the 107 drug development programs identified 150 pivotal trials that were subsequently analyzed. The pivotal trials were mostly randomized (80%) and blinded (69.3%). Biomarkers (41.1%) and clinical outcomes (42.1%) were commonly utilized as primary efficacy endpoints. Analysis of the use of clinical trial design elements across trials that utilized biomarkers, clinical outcomes, or composite endpoints did not reveal statistically significant differences. The choice of primary efficacy endpoint varied by the drug’s therapeutic area, approval pathway, and whether the indicated disease etiology was well defined. For example, biomarkers were commonly selected as primary efficacy endpoints in hematology drug approvals (70.6%), whereas clinical outcomes were commonly selected in neurology drug approvals (69.6%). Further, if the disease etiology was well defined, biomarkers were more commonly used as primary efficacy endpoints in pivotal trials (44.7%) than if the disease etiology was not well defined (27.3%). Discussion In the past 10 years, numerous novel drugs have been approved to treat non-oncologic rare diseases in various therapeutic areas. To demonstrate their efficacy for regulatory approval, biomarkers and clinical outcomes were commonly utilized as primary efficacy endpoints. Biomarkers were not only frequently used as surrogate efficacy endpoints in accelerated approvals, but also in traditionally approved rare disease drugs. The choice of primary efficacy endpoints varied by therapeutic area, approval pathway, and understanding of disease etiology.

Hong, Kyungwan [Rare Diseases Team, Office of New ↗