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Soft Metal Cations Trigger Sandwich-Cluster Luminescence of a New Au(I)-Vinylimidazolate Cyclic Trinuclear Complex (open access)

Soft Metal Cations Trigger Sandwich-Cluster Luminescence of a New Au(I)-Vinylimidazolate Cyclic Trinuclear Complex

Article presenting results from a study where a new gold(I)-vinylimidazolate CTC, 1, was prepared and the formation of highly emissive sandwich adducts with the soft metal cations Cu+, Ag+, and Tl+, 2–4, respectively, was investigated.
Date: February 14, 2022
Creator: Lu, Zhou; Burini, Alfredo; McDougald, Roy N., Jr.; Ricci, Simone; Luciani, Lorenzo; Nesterov, Vladimir N. et al.
System: The UNT Digital Library
Soft Metal Cations Trigger Sandwich-Cluster Luminescence of a New Au(I)-Vinylimidazolate Cyclic Trinuclear Complex (open access)

Soft Metal Cations Trigger Sandwich-Cluster Luminescence of a New Au(I)-Vinylimidazolate Cyclic Trinuclear Complex

Article presenting research that obtained a new Au(I) CTC bearing the 1-vinylimidazolate ligand and furthered the controllable synthetic pathway to afford heterometallic sandwich-like clusters.
Date: February 14, 2022
Creator: Lu, Zhou; Burini, Alfredo; McDougald, Roy N., Jr.; Ricci, Simone; Luciani, Lorenzo; Nesterov, Vladimir N. et al.
System: The UNT Digital Library
The impact agenda and the search for a good life (open access)

The impact agenda and the search for a good life

This article is published as part of a collection on the future of research assessment. It explores the philosophies of Plato and Aristotle concerning the impact agenda and how philosophy can assist policy questions. Together, their work suggests that policy-sensitive philosophers can help decision makers be more self-conscious about the assumptions underlying their work.
Date: February 14, 2017
Creator: Frodeman, Robert
System: The UNT Digital Library
Small-scale mechanical behavior of a eutectic high entropy alloy (open access)

Small-scale mechanical behavior of a eutectic high entropy alloy

Article describes study evaluating small-scale mechanical behavior was for AlCoCrFeNi2.1 eutectic high entropy alloy, consisting of a lamellar arrangement of L12 and B2 solid-solution phases.
Date: February 14, 2020
Creator: Muskeri, Saideep; Hasannaeimi, Vahid; Salloom, Riyadh; Sadeghilaridjani, Maryam & Mukherjee, Sundeep
System: The UNT Digital Library
Latent Class Analysis Offers Insight into the Complex Food Environments of Native American Communities: Findings from the Randomly Selected OPREVENT2 Trial Baseline Sample (open access)

Latent Class Analysis Offers Insight into the Complex Food Environments of Native American Communities: Findings from the Randomly Selected OPREVENT2 Trial Baseline Sample

The article describes the subgroups and demographic characteristics related to NA household food environments. Surveys collected food getting, food assistance, and sociodemographic variables from randomly selected adults from three NA communities (n = 300) in the Midwest and Southwest. Findings demonstrate that NA household food environments can be described by developing subgroups based on patterns of market and traditional food getting, and food assistance utilization. Understanding NA household food environments could identify tailored individual and community-level approaches to promoting healthy eating for NA Nations.
Date: February 14, 2020
Creator: Jock, Brittany Wenniseí:iostha; Bandeen Roche, Karen; Caldas, Stephanie; Redmond, Leslie; Fleischhacker, Sheila & Gittelsohn, Joel
System: The UNT Digital Library
Entropic Approach to the Detection of Crucial Events (open access)

Entropic Approach to the Detection of Crucial Events

This article establishes a clear distinction between two processes yielding anomalous diffusion and 1/ f noise. One of the processes, Aging Fractional Brownian Motion (AFBM), has been concluded to be the form of communication between the heart and the brain.
Date: December 22, 2018
Creator: Culbreth, Garland; West, Bruce J. & Grigolini, Paolo
System: The UNT Digital Library
New mechanism of plasmons specific for spin-polarized nanoparticles (open access)

New mechanism of plasmons specific for spin-polarized nanoparticles

This article experimentally shows that Co nanoparticles with a single-domain crystal structure support a plasmon resonance at approximately 280 nm with better quality than gold nanoparticle resonance in the visible. The magnetic nature of these nanoparticles suggests a new type of these plasmons.
Date: March 27, 2018
Creator: Bhatta, Hari L.; Aliev, Abil E. & Drachev, Vladimir P.
System: The UNT Digital Library
Automatic Generation of Data Types for Classification of Deep Web Sources (open access)

Automatic Generation of Data Types for Classification of Deep Web Sources

A Service Class Description (SCD) is an effective meta-data based approach for discovering Deep Web sources whose data exhibit some regular patterns. However, it is tedious and error prone to create an SCD description manually. Moreover, a manually created SCD is not adaptive to the frequent changes of Web sources. It requires its creator to identify all the possible input and output types of a service a priori. In many domains, it is impossible to exhaustively list all the possible input and output data types of a source in advance. In this paper, we describe machine learning approaches for automatic generation of the data types of an SCD. We propose two different approaches for learning data types of a class of Web sources. The Brute-Force Learner is able to generate data types that can achieve high recall, but with low precision. The Clustering-based Learner generates data types that have a high precision rate, but with a lower recall rate. We demonstrate the feasibility of these two learning-based solutions for automatic generation of data types for citation Web sources and presented a quantitative evaluation of these two solutions.
Date: February 14, 2005
Creator: Ngu, A. H.; Buttler, D. J. & Critchlow, T. J.
System: The UNT Digital Library
The Importance of Geometric Nonlinearity in Finite Element Studies of Yielding in Trabecular Bone (open access)

The Importance of Geometric Nonlinearity in Finite Element Studies of Yielding in Trabecular Bone

None
Date: February 14, 2005
Creator: Kinney, J H & Stolken, J S
System: The UNT Digital Library
Torsional Buckling and Writhing Dynamics of Elastic Cables and DNA (open access)

Torsional Buckling and Writhing Dynamics of Elastic Cables and DNA

Marine cables under low tension and torsion on the sea floor can undergo a dynamic buckling process during which torsional strain energy is converted to bending strain energy. The resulting three-dimensional cable geometries can be highly contorted and include loops and tangles. Similar geometries are known to exist for supercoiled DNA and these also arise from the conversion of torsional strain energy to bending strain energy or, kinematically, a conversion of twist to writhe. A dynamic form of Kirchhoff rod theory is presented herein that captures these nonlinear dynamic processes. The resulting theory is discretized using the generalized-method for finite differencing in both space and time. The important kinematics of cross-section rotation are described using an incremental rotation ''vector'' as opposed to traditional Euler angles or Euler parameters. Numerical solutions are presented for an example system of a cable subjected to increasing twist at one end. The solutions show the dynamic evolution of the cable from an initially straight element, through a buckled element in the approximate form of a helix, and through the dynamic collapse of this helix through a looped form.
Date: February 14, 2003
Creator: Goyal, S; Perkins, N C & Lee, C L
System: The UNT Digital Library
Cost-Effective Sampling of Groundwater Monitoring Wells: A Data Review & Well Frequency Evaluation (open access)

Cost-Effective Sampling of Groundwater Monitoring Wells: A Data Review & Well Frequency Evaluation

Lawrence Livermore National Laboratory (LLNL) uses the Cost-Effective Sampling (CES) program for reviewing groundwater data and optimizing the site's groundwater monitoring plan. The CES program produces a data assessment sheet and a lowest-frequency sampling schedule for each groundwater monitoring location. The assessment sheet and recommended sampling schedule greatly streamline the data review process and provide useful information for regulatory and remedial decision-making. The determination of sampling frequency for a given location is based on trend, variability, and magnitude statistics. The underlying principle is that a location's schedule should be determined primarily by the rate of change in concentrations observed there in the recent past. The larger the rate of change, whether upward or downward, the greater the need for frequent sampling. Conversely, where little change is observed, less sampling is recommended. In 1992, CES was approved by the U.S. EPA - Region IX and the local regulators for use at LLNL, and became part of the LLNL's approved compliance monitoring plan (Lamarre et al. 1996). Applying the CES methodology produced, initially, a 40% reduction in the annual number of required groundwater samples, and with recent optimization of the program a 55% reduction has been produced. This reduction saves LLNL $530,000 …
Date: February 14, 2005
Creator: Ridley, M. & MacQueen, D.
System: The UNT Digital Library
Crystallization of Beryllium-Boron Metallic Glasses (open access)

Crystallization of Beryllium-Boron Metallic Glasses

Prior studies of evaporation and sputter deposition show that the grain size of pure beryllium can be dramatically refined through the incorporation of metal impurities. Recently, the addition of boron at a concentration greater than 11% is shown to serve as a glassy phase former in sputter deposited beryllium. Presently, thermally induced crystallization of the beryllium-boron metallic glass is reported. The samples are characterized during an in-situ anneal treatment with bright field imaging and electron diffraction using transmission electron microscopy. A nanocrystalline structure evolves from the annealed amorphous phase and the crystallization temperature is affected by the boron concentration.
Date: February 14, 2002
Creator: Jankowski, Alan Frederic; Wall, M. A. & Nieh, T. G.
System: The UNT Digital Library
Semi-quantitative analysis of microstructures by secondary ion mass spectrometry (open access)

Semi-quantitative analysis of microstructures by secondary ion mass spectrometry

The focus of this review is on trace-element quantitation of microstructures in solids. This review is aimed at the non-specialist who wants to know how SIMS quantitation is achieved. Despite 35 years of SIMS research and applications, SIMS quantitation remains a fundamentally empirical enterprise and is based on standards. The most used standards are ''bulk standards''--solids with a homogeneous distribution of a trace element--and ion-implanted solids. The SIMS systematics of bulk standards and ion-implanted solids are reviewed.
Date: February 14, 2005
Creator: Phinney, D L
System: The UNT Digital Library
Raising the Level of Programming Abstraction in Scalable Programming Models (open access)

Raising the Level of Programming Abstraction in Scalable Programming Models

The complexity of modern scientific simulations combined with the complexity of the high-performance computer hardware on which they run places an ever-increasing burden on scientific software developers, with clear impacts on both productivity and performance. We argue that raising the level of abstraction of the programming model/environment is a key element of addressing this situation. We present examples of two distinctly different approaches to raising the level of abstraction of the programming model while maintaining or increasing performance: the Tensor Contraction engine, a narrowly-focused domain specific language together with an optimizing compiler; and Extended Global Arrays, a programming framework that integrates programming models dealing with different layers of the memory/storage hierarchy using compiler analysis and code transformation techniques.
Date: February 14, 2004
Creator: Bernholdt, David E.; Nieplocha, Jarek & Sadayappan, Ponnuswamy
System: The UNT Digital Library
Quantifying Flaw Characteristics from IR NDE Data (open access)

Quantifying Flaw Characteristics from IR NDE Data

Work is presented which allows flaw characteristics to be quantified from the transient IR NDE signature. The goal of this effort was to accurately determine the type, size and depth of flaws revealed with IR NDE, using sonic IR as the example IR NDE technique. Typically an IR NDE experiment will result in a positive qualitative indication of a flaw such as a cold or hot spot in the image, but will not provide quantitative data thereby leaving the practitioner to make educated guesses as to the source of the signal. The technique presented here relies on comparing the transient IR signature to exact heat transfer analytical results for prototypical flaws, using the flaw characteristics as unknown fitting parameters. A nonlinear least squares algorithm is used to evaluate the fitting parameters, which then provide a direct measure of the flaw characteristics that can be mapped to the imaged surface for visual reference. The method uses temperature data for the heat transfer analysis, so radiometric calibration of the IR signal is required. The method provides quantitative data with a single thermal event (e.g. acoustic pulse or flash), as compared to phase-lock techniques that require many events. The work has been tested …
Date: February 14, 2003
Creator: Miller, W; Philips, N R; Burke, M W & Robbins, C L
System: The UNT Digital Library
A Comparison of the Effect of Temperature on the Passivity Breakdown and Repassivation Potentials of Wrought and Welded Alloy 22 in 5 M CAC12 (open access)

A Comparison of the Effect of Temperature on the Passivity Breakdown and Repassivation Potentials of Wrought and Welded Alloy 22 in 5 M CAC12

The study of the electrochemical behavior of wrought and welded Alloy 22 was carried out in 5 M CaC12 at various temperatures. Comparisons were made between the electrochemical behaviors of the wrought and welded forms of Alloy 22 Multiple Crevice Assembly (MCA) specimens. The susceptibility to corrosion was found to increase with increase in temperature in both the wrought and the welded forms of the alloy: Nevertheless, the measure critical breakdown potential E{sub crit} was found to be Similar for the wrought and welded specimens.
Date: February 14, 2003
Creator: Ilevbare, G
System: The UNT Digital Library
REVERSIBLE N-BIT TO N-BIT INTEGER HAAR-LIKE TRANSFORMS (open access)

REVERSIBLE N-BIT TO N-BIT INTEGER HAAR-LIKE TRANSFORMS

We introduce TLHaar, an n-bit to n-bit reversible transform similar to the Haar IntegerWavelet Transform (IWT). TLHaar uses lookup tables that approximate the Haar IWT, but reorder the coefficients so they fit into n bits. TLHaar is suited for lossless compression in fixed-width channels, such as digital video channels and graphics hardware frame buffers.
Date: February 14, 2004
Creator: Duchaineau, M; Joy, K I & Senecal, J
System: The UNT Digital Library
Milling and blending of ceramic powders for the plutonium immobilization program (open access)

Milling and blending of ceramic powders for the plutonium immobilization program

The goal of the Plutonium Immobilization Program is the immobilization of surplus weapons usable plutonium in a ceramic form. The ceramic will then be encapsulated in high level waste glass using the can-in-can configuration. In the ceramic line of the immobilization plant, surplus plutonium oxide of less than 100 micron particle size will be received for immobilization. The plutonium oxide must be sized reduced and intimately blended with uranium oxide and the other ceramic forming materials containing neutron poisons to allow for complete interaction during sintering. Once properly blended, the formulation will be pressed into the desired ceramic form and then sintered to produce the targeted mineral phases. The equipment of choice for the size reduction of the actinides and the blending with the precursor materials is the Union Process attritor mill. The attritor mill is best described as a stirred ball mill and consists of a stationary tank filled with grinding media that is agitated by a shaft with stirring arms. The rotational shaft stirs the media at high-speed causing shearing and impact forces on the material resulting in size reduction and dispersion. Speeds over 1000 rpm can be reached by the stirring shaft. The high-speed of the attritor …
Date: February 14, 2000
Creator: Herman, D. T. & Biehl, W. E.
System: The UNT Digital Library
Domain-specific Web Service Discovery with Service Class Descriptions (open access)

Domain-specific Web Service Discovery with Service Class Descriptions

This paper presents DynaBot, a domain-specific web service discovery system. The core idea of the DynaBot service discovery system is to use domain-specific service class descriptions powered by an intelligent Deep Web crawler. In contrast to current registry-based service discovery systems--like the several available UDDI registries--DynaBot promotes focused crawling of the Deep Web of services and discovers candidate services that are relevant to the domain of interest. It uses intelligent filtering algorithms to match services found by focused crawling with the domain-specific service class descriptions. We demonstrate the capability of DynaBot through the BLAST service discovery scenario and describe our initial experience with DynaBot.
Date: February 14, 2005
Creator: Rocco, Daniel; Caverlee, James; Liu, Ling & Critchlow, Terence J.
System: The UNT Digital Library
A Dynamically Adaptive Arbitrary Lagrangian-Eulerian Method for Solution of the Euler Equations (open access)

A Dynamically Adaptive Arbitrary Lagrangian-Eulerian Method for Solution of the Euler Equations

A new method that combines staggered grid arbitrary Lagrangian-Eulerian (ALE) techniques with structured local adaptive mesh refinement (AMR) has been developed for solution of the Euler equations. The novel components of the methods are driven by the need to reconcile traditional AMR techniques with the staggered variables and moving, deforming meshes associated with Lagrange based ALE schemes. We develop interlevel solution transfer operators and interlevel boundary conditions first in the case of purely Lagrangian hydrodynamics, and then extend these ideas into an ALE method by developing adaptive extensions of elliptic mesh relaxation techniques. Conservation properties of the method are analyzed, and a series of test problem calculations are presented which demonstrate the utility and efficiency of the method.
Date: February 14, 2003
Creator: Anderson, R W; Elliott, N S & Pember, R B
System: The UNT Digital Library
The Value of Energy Storage for Direct-Replacement Solar Thermal Power Plants (open access)

The Value of Energy Storage for Direct-Replacement Solar Thermal Power Plants

None
Date: February 14, 1978
Creator: Anderson, T.; Kaplan, S. & Wilson, J.
System: The UNT Digital Library
The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste (open access)

The Y-12 Plant No Rad-Added Program for off-site shipment of nonradioactive hazardous waste

On May 17, 1991, the US Department of Energy (DOE) issued a directive for DOE operations to cease off-site shipments of non-radioactive hazardous waste pending further clarification and approvals. A DOE Performance Objective for Certification of Non-Radioactive Hazardous Waste was issued in November 1991. In response to these directives, the Waste Management Division of Oak Ridge Y-12 Plant, with assistance from Roy F. Weston, Inc., has developed a No Rad-Added Program to provide small programmatic guidance and a set of procedures, approved by DOE, which will permit hazardous waste to be shipped from the Y-12 Plant to commercial treatment, storage, or disposal facilities after ensuring and certifying that hazardous waste has no radioactivity added as a result of DOE operations. There are serious legal and financial consequences of shipping waste containing radioactivity to an off-site facility not licensed to receive radioactive materials. Therefore, this program is designed with well-defined responsibilities and stringent documentation requirements.
Date: February 14, 1994
Creator: Cooper, K. H.; Mattie, B. K.; Williams, J. L.; Jacobs, D. G. & Roberts, K. A.
System: The UNT Digital Library
Application of probabilistic risk assessment methods to incinerator design and permitting (open access)

Application of probabilistic risk assessment methods to incinerator design and permitting

The Consolidated Incineration Facility at the Savannah River Site is designed without emergency flue gas vents. The main components of this 18 million btu/hr facility are a rotary kiln and secondary combustion chamber, each with a code allowable internal pressure of 15 psig. The facility is designed to treat mixed waste. During the early stages of design it was judged on a qualitative basis that potential eventsthat might produce damaging overpressures were not credible. When these findings were questioned during subsequent design reviews, a probabilistic risk assessment was undertaken to provide a quantitative basis for decision making. The result was identification of design conditions leading to relatively high frequencies for a few event sequences in which the allowable pressure might be exceeded. Risk assessment assumptions and results were reviewed with design engineers and relatively simple improvements were identified that collectively reduced the frequency of overpressure to an acceptable level. This experience showed that the use of formalized risk assessment techniques can provide valuable insight leading to timely and cost-effective improvements in facility design and operating procedures. In this case, the program of analysis and follow-on improvements provided justification for incinerator operation without thermal relief devices.
Date: February 14, 1993
Creator: Brown, E. A.; McAfee, D. E. & Aabye, D. C.
System: The UNT Digital Library
Implications of ethanol-based fuels for greenhouse gas emissions (open access)

Implications of ethanol-based fuels for greenhouse gas emissions

The US Environmental Protection Agency has proposed a rule which would mandate that 30% of the oxygen content of reformulated gasoline be provided by renewable oxygenates. The rule would essentially require that biomass-based ethanol, or ETBE derived from ethanol, be used to supply 30% of the oxygen in reformulated gasoline. This short statement addresses the very narrow question, ``Would this rule result in a net decrease in greenhouse gas emissions?`` The challenge then is to determine how much greenhouse gas is emitted during the ethanol fuel cycle, a fuel cycle that is much less mature and less well documented than the petroleum fuel cycle. In the petroleum fuel cycle, most of the greenhouse gas emissions come from fuel combustion. In the ethanol fuel cycle most of the greenhouse gas emissions come from the fuel production processes. Details of corn productivity, fertilizer use, process efficiency, fuel source, etc. become very important. It is also important that the ethanol fuel cycle produces additional products and the greenhouse gas emissions have somehow to be allocated among the respective products. With so many variables in the ethanol fuel cycle, the concern is actually with ethanol-based additives which will be produced in response to the …
Date: February 14, 1994
Creator: Marland, G.; DeLuchi, M. A. & Wyman, C.
System: The UNT Digital Library