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The Virtual Manual: Moving from Paper- to Web-Based Documentation (open access)

The Virtual Manual: Moving from Paper- to Web-Based Documentation

Lawrence Livermore National Laboratory is implementing an Integrated Safety Management System (ISMS) to assure that all environment, safety, and health (ES&H) requirements and practices are integrated into work planning, execution, and feedback. A major component to ISMS is the rewriting of the Laboratory's ES&H documentation to meet federal, state, and local requirements and standards. Previously, the Laboratory's operations documentation was paper-based and decentralized; updates were time-consuming and expensive to produce and distribute. The immediate goal for the ISMS project team was the development of a virtual, Web-based manual that provides current, consistent information easily accessible to users. Future updates to this virtual manual will be faster, less expensive, and immediately available.
Date: August 16, 1999
Creator: Cannon, Gloria; Butler, Janice; Corey, Cara Wilson & Hedman, Irene
System: The UNT Digital Library
The Chemical Equilibration Volume: Measuring the Degree of Thermalization (open access)

The Chemical Equilibration Volume: Measuring the Degree of Thermalization

This report talks about The Chemical Equilibration Volume: Measuring the Degree of Thermalization
Date: May 16, 2003
Creator: Majumder, Abhijit & Koch, Volker
System: The UNT Digital Library
Friction stir welding of SS 316 LN and Nitronic 50 jacket sections for application in superconducting fusion magnet systems (open access)

Friction stir welding of SS 316 LN and Nitronic 50 jacket sections for application in superconducting fusion magnet systems

Article explores the possibility of using friction stir welding (FSW) to join jacket web sections of two nitrogen-containing stainless steels for housing internally cooled superconducting cables which are utilized to generate magnetic fields in tokamak type fusion reactor systems. It has been shown that the FSW fabricated SS 316 LN jackets possessed the required strength and magnetic properties critical to this application.
Date: July 16, 2022
Creator: Gaddam, Supreeth; Haridas, Ravi Sankar; Sanabria, Charlie; Tammana, Deepthi; Berman, Diana & Mishra, R. S.
System: The UNT Digital Library
Advanced Air Mobility Operation and Infrastructure for Sustainable Connected eVTOL Vehicle (open access)

Advanced Air Mobility Operation and Infrastructure for Sustainable Connected eVTOL Vehicle

Article discusses how advanced air mobility (AAM) is an emerging sector in aviation aiming to offer secure, efficient, and eco-friendly transportation utilizing electric vertical takeoff and landing (eVTOL) aircraft. This paper introduces a novel concept addressing future flight challenges and proposes a framework for integrating operations, infrastructure, connectivity, and ecosystems in future air mobility.
Date: May 16, 2023
Creator: Al-Rubaye, Saba; Tsourdos, Antonios & Namuduri, Kamesh
System: The UNT Digital Library
Search for CP Violation in the Decay tau- \to pi- K^0_S (>= 0 pi0) nu_tau (open access)

Search for CP Violation in the Decay tau- \to pi- K^0_S (>= 0 pi0) nu_tau

We report a search for CP violation in the decay {tau}{sup -} {yields} {pi}{sup -}K{sub S}{sup 0}({>=} 0{pi}{sup 0}){nu}{sub {tau}} using a dataset of 437 million {tau} lepton pairs, corresponding to an integrated luminosity of 476 fb{sup -1}, collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings. The CP-violating decay-rate asymmetry is determined to be (-0.45 {+-} 0.24 {+-} 0.11)%, approximately three standard deviations from the Standard Model prediction of (0.33 {+-} 0.01)%.
Date: February 16, 2012
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M. et al.
System: The UNT Digital Library
Development of an odd-Z-projectile reaction for heavy element synthesis: 208Pb(64Ni, n)271Ds and 208Pb(65Cu, n)272111 (open access)

Development of an odd-Z-projectile reaction for heavy element synthesis: 208Pb(64Ni, n)271Ds and 208Pb(65Cu, n)272111

Seven {sup 271}Ds decay chains were identified in the bombardment of {sup 208}Pb targets with 311.5- and 314.3-MeV {sup 64}Ni projectiles using the Berkeley Gas-filled Separator. These data, combined with previous results, provide an excitation function for this reaction. From these results, an optimum energy of 321 MeV was estimated for the production of {sup 272}111 in the reaction {sup 208}Pb({sup 65}Cu, n). One decay chain was observed, resulting in a cross section of 1.7{sub -1.4}{sup +3.9} pb. This experiment confirms the discovery of element 111 by the Darmstadt group who used the {sup 209}Bi({sup 64}Ni, n){sup 272}111 reaction.
Date: August 16, 2004
Creator: Folden, C. M., III; Gregorich, K. E.; Dullmann, Ch. E.; Mahmud, H.; Pang, G. K.; Schwantes, J. M. et al.
System: The UNT Digital Library
Performance of a total-flow impulse turbine for geothermal applications (open access)

Performance of a total-flow impulse turbine for geothermal applications

A new, axial-flow impulse turbine was tested at LLL as part of the geothermal energy development program. Engine efficiency of this single-stage, two-phase expander was measured at 23% during a single-nozzle test. Performance predictions of a numerical model agreed with these results. Full-admission performance (based on the numerical-model and attainable nozzle thrust coefficients) indicates that engine efficiency can reach between 38 and 40% with present technology. Improved techniques for analyzing two-phase flow and further reduction of droplet sizes should provide 70% engine efficiency.
Date: May 16, 1977
Creator: Comfort, W. J., III
System: The UNT Digital Library
Single-Bunch Instability Driven by the Electron Cloud Effect inthe Positron Damping Ring of the International Linear Collider (open access)

Single-Bunch Instability Driven by the Electron Cloud Effect inthe Positron Damping Ring of the International Linear Collider

Collective instabilities caused by the formation of an electron cloud (EC) are a potential limitation to the performances of the damping rings for a future linear collider. In this paper, we present recent simulation results for the electron cloud build-up in damping rings of different circumferences and discuss the single-bunch instabilities driven by the electron cloud.
Date: May 16, 2005
Creator: Pivi, Mauro; Raubenheimer, Tor O.; Ghalam, Ali; Harkay, Katherine; Ohmi, Kazuhito; Wanzenberg, Rainer et al.
System: The UNT Digital Library
Excitation function for the production of 262Bh (Z = 107) in theodd-Z projectile reaction 208Pb(55Mn, n) (open access)

Excitation function for the production of 262Bh (Z = 107) in theodd-Z projectile reaction 208Pb(55Mn, n)

The excitation function for production of 262Bh in the odd-Z-projectile reaction 208Pb(55Mn,n) has been measured at three projectile energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, 33 decay chains originating from 262Bh and 2 decay chains originating from 261Bh were observed. The measured decay properties are in good agreement with previous reports. The maximum cross section of 540 +180 - 150 pb is observed at a lab-frame center-of-target energy of 264.0 MeV and is more than fives times larger than that expected based on previously reported results for production of 262Bh in the analogous even-Z-projectile reaction 209Bi(54Cr,n). Our results indicate that the optimum beam energy in one-neutron-out heavy-ion fusion reactions can be estimated simply using the ''Optimum Energy Rule'' proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski.
Date: May 16, 2005
Creator: Folden, C. M., III; Nelson, S. L.; Dullmann, Ch. E.; Schwantes, J. M.; Sudowe, R.; Zielinski, P. M. et al.
System: The UNT Digital Library
X-Ray Digital Radiography and Computed Tomography Characterization of Targets (open access)

X-Ray Digital Radiography and Computed Tomography Characterization of Targets

The summary of this report is: (1) The Xradia Micro XCT and LLNL CCAT x-ray systems are used to nondestructively characterize a variety of materials, assemblies, and reference standard components; (2) The digital radiograph (DR) and computed tomography (CT) image data may be used for metrology, quality control, and defect detection; and (3) The ability to detect and characterize imperfections leads to improvements in the manufacturing processes for assemblies.
Date: April 16, 2008
Creator: Sain, J. D.; Brown, W. D.; Chinn, D. J.; Martz, H. E., Jr.; Morales, K. E.; Schneberk, D. J. et al.
System: The UNT Digital Library
Thermal Modeling of TIVA Profiles of a Polysilcon-Metal Test Structure (open access)

Thermal Modeling of TIVA Profiles of a Polysilcon-Metal Test Structure

Thermal modeling and simulations were used to analyze the thermal profiles of a polysilicon-metal test structure generated by thermally-induced voltage alteration (TIVA), a new laser-based failure analysis technique to localize shorted interconnects. The results show that variations in TIVA thermal profiles are due mainly to preferential laser absorption in various locations in the test structure. Differences in oxide thickness also affect the local heat conduction and temperature distribution. Modeling results also show that local variation in heat conduction is less important than the absorbed laser power in determining the local temperatures since our test structure has feature sizes that are small compared to the length over which heat spreads.
Date: September 16, 1999
Creator: Benson, D. A.; Cole, E. I., Jr. & Tangyunyong, Paiboon
System: The UNT Digital Library
Solar Neutrinos. II. Experimental (open access)

Solar Neutrinos. II. Experimental

A method is described for observing solar neutrinos from the reaction Cl/ sup 37/( nu ,e/sup -/)Ar/sup 37/ in C/sub 2/Cl/sub 4/. Two 5 00-gal tanks of C/ sub 2/Cl/sub 4/ were placed in a limestone mine (1800 m.w.e.) and the resulting Ar/sup 37/ activity induced by cosmic mesons( mu ) was measured to determine the necessary conditions for solar neutrino observations. (R.E.U.)
Date: March 16, 1964
Creator: Davis, R., Jr.
System: The UNT Digital Library
Integrated Safety Management System Safety Culture Improvement Initiative (open access)

Integrated Safety Management System Safety Culture Improvement Initiative

In 2007, the Department of Energy (DOE) identified safety culture as one of their top Integrated Safety Management System (ISMS) related priorities. A team was formed to address this issue. The team identified a consensus set of safety culture principles, along with implementation practices that could be used by DOE, NNSA, and their contractors. Documented improvement tools were identified and communicated to contractors participating in a year long pilot project. After a year, lessons learned will be collected and a path forward determined. The goal of this effort was to achieve improved safety and mission performance through ISMS continuous improvement. The focus of ISMS improvement was safety culture improvement building on operating experience from similar industries such as the domestic and international commercial nuclear and chemical industry.
Date: January 16, 2009
Creator: McDonald, J. A., Jr.
System: The UNT Digital Library
Geochemical Behavior of the Second Hot Dry Rock Geothermal Reservoir at Fenton Hill, New Mexico (open access)

Geochemical Behavior of the Second Hot Dry Rock Geothermal Reservoir at Fenton Hill, New Mexico

Characteristics of a Hot Dry Rock (HDR) geothermal reservoir were deduced by matching a geochemistry model which incorporates rock dissolution and displacement of an indigenous pore-fluid to chemical analyses of recirculating geothermal fluid. Two reservoirs were created between a pair of wells by hydraulic fracturing. The first of the reservoirs was evaluated by a 75-day flow test designated as Segment 2. Subsequent operations required the cementing of the injection well to stop a leak behind the casing, and this cementing operation closed the connection to the first reservoir. The second, larger reservoir was evaluated with two flow tests -- the first had a duration of 24 days and is c a l l e d Segment 4 and the second, called Segment 5, will end on December 19, 1980 after 284 days of operation. Present discussion w i l l be mainly concerned with the geochemistry of the second reservoir. Of particular interest in a HDR geothermal reservoir is the relationship between the mixed-mean temperature of the geothermal fluid as measured with a downhole thermistor and the temperatures given by the silica and the Na-K-Ca geochemical thermometers. As will be shown, the temperatures predicted by applying the chemical geothermometers directly …
Date: December 16, 1980
Creator: Grigsby, Charles O.; Trujillo, P. E., Jr.; Counce, D. A. & Aguilar, R. G.
System: The UNT Digital Library
Hedgehog signaling is involved in acquired resistance to KRASG12C inhibitors in lung cancer cells (open access)

Hedgehog signaling is involved in acquired resistance to KRASG12C inhibitors in lung cancer cells

Article states that although KRASG12C inhibitors have shown promising activity in lung adenocarcinomas harboring KRASG12C, acquired resistance to these therapies eventually occurs in most patients. The authors report that the hedgehog signal is induced by KRASG12C inhibitors and mediates KRAS re-expression in cancer cells treated with a KRASG12C inhibitor.
Date: January 16, 2024
Creator: Lee, Chaeyoung; Yi, Jawoon; Park, Jihwan; Ahn, Byungyong; Won, Young-Wook; Jeon, JiHeung et al.
System: The UNT Digital Library
The Interface Strengthening of Multi-Walled Carbon Nanotubes/Polylactic Acid Composites via the In-Loop Hybrid Manufacturing Method (open access)

The Interface Strengthening of Multi-Walled Carbon Nanotubes/Polylactic Acid Composites via the In-Loop Hybrid Manufacturing Method

Article describes how in this study, a new in-loop hybrid manufacturing method is proposed for fabricating multi-walled carbon nanotube (MWCNTs)/polylactic acid (PLA) composites. Molecular dynamics simulations were conducted in conjunction with experiments to reveal the mechanism of the proposed method for improving the interfacial performance of MWCNTs/PLA.
Date: November 16, 2023
Creator: Li, Hongbin; Jiang, Zhuang; Li, Zhihua; Peng, Yubao; Zhang, Qiushuang & Xiao, Xinyi
System: The UNT Digital Library
Development and Utilization of Bridge Data of the United States for Predicting Deck Condition Rating Using Random Forest, XGBoost, and Artificial Neural Network (open access)

Development and Utilization of Bridge Data of the United States for Predicting Deck Condition Rating Using Random Forest, XGBoost, and Artificial Neural Network

Article describes how accurately predicting the condition rating of a bridge deck is crucial for effective maintenance and repair planning. This study aims to assess the effectiveness of these algorithms for deck condition rating prediction at the national level.
Date: January 16, 2024
Creator: Fard, Fariba & Fard, Fereshteh Sadeghi Naieni
System: The UNT Digital Library
A brief guide to polymer characterization: structure (IUPAC Technical Report) (open access)

A brief guide to polymer characterization: structure (IUPAC Technical Report)

Article states that to bolster the series of Brief Guides released by International Union of Pure and Applied Chemistry, the authors introduce the first Brief Guide to Polymer Characterization. This article provides a concise overview of characterization methods for teachers, students, non-specialists, and newcomers to polymer science as well as being a useful manual for researchers and technicians.
Date: August 16, 2023
Creator: Topham, Paul D.; Boucher, Raymond J.; Chang, Taihyun; Smrčková, Miroslava D.; Farrell, Wesley S.; He, Jiasong et al.
System: The UNT Digital Library
Imaging Detectors for 20-100 ke V X-ray Backlighters in HEDES Petawatt Experiments (open access)

Imaging Detectors for 20-100 ke V X-ray Backlighters in HEDES Petawatt Experiments

We are developing a petawatt laser for use as a high energy backlighter source in the 20{approx} 100 keV range. High energy x-ray backlighters will be essential for radiographing High-Energy- Density Experimental Science (HEDES) targets for NIF projects especially to probe implosions and high areal density planar samples. For these experiments we are employing two types of detectors: a columnar grown CsI scintillator coupled to a 2K x 2K CCD camera and a CdTe crystal with a special ASIC readout electronics in a 508 x 512 format array. We have characterized these sensors using radioactive sources. In addition, we utilized them to measure the Sm K{alpha} source size generated by the short pulse laser, JanUSP, at LLNL. This paper will present the results of our characterizations of these detectors.
Date: April 16, 2004
Creator: Wickersham, J. E.; Park, H.; Bell, P. M.; Koch, J. A.; Landen, O. L. & Moody, J. D.
System: The UNT Digital Library