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The 1989 Malcolm Baldrige award winners - Milliken and Company; and Xerox Business Products and Services are highlighted in this video. Their strategies for producing quality products are discussed, along with their applications and importance in today's competitive workplace.
The award provided funds for a tracking video camera. The camera has been installed and the system calibrated. It has enabled us to follow in real time the tracks of individual wood ants (Formica rufa) within a 3m square arena as they navigate singly in-doors guided by visual cues. To date we have been using the system on two projects. The first is an analysis of the navigational strategies that ants use when guided by an extended landmark (a low wall) to a feeding site. After a brief training period, ants are able to keep a defined distance and angle from the wall, using their memory of the wall's height on the retina as a controlling parameter. By training with walls of one height and length and testing with walls of different heights and lengths, we can show that ants adjust their distance from the wall so as to keep the wall at the height that they learned during training. Thus, their distance from the base of a tall wall is further than it is from the training wall, and the distance is shorter when the wall is low. The stopping point of the trajectory is defined precisely by the angle that the far end of the wall makes with the trajectory. Thus, ants walk further if the wall is extended in length and not so far if the wall is shortened. These experiments represent the first case in which the controlling parameters of an extended trajectory can be defined with some certainty. It raises many questions for future research that we are now pursuing.
Affordable fiber-reinforced ceramic matrix composites (AFReCC) with high strength and toughness, good thermal conductivity, thermal shock resistance, and oxidation resistance are needed for high-temperature structural applications. AFReCC materials will have various applications in advanced high-efficiency and high-performance engines: that is, the High Speed Civil Transport (HSCT), space propulsion components, and land-based systems. For example, silicon-carbide-fiber-reinforced silicon carbide matrix composites show promise for meeting the criteria of high strength, thermal conductivity, and toughness required for the HSCT combustor liner. AFReCC received R&D Magazine's prestigious R&D 100 Award in 1995. The fabrication process for these composites has three steps. In the first step, fiber preforms are made and chemical vapor infiltration is used to apply the desired interface coating on the fibers. This step also rigidizes the preform. The second step consists of resin infiltration, which after pyrolysis, yields an interconnected network of porous carbon as the matrix. In the final step of the process, the carbon-containing preform is infiltrated with molten silicon or silicon alloys in a furnace. This converts the carbon to silicon carbide leaving as little as 5 percent residual free silicon or refractory disilicide phase. This process is suitable for any type of small-diameter fiber (e.g., carbon, alumina, or silicon carbide) woven into a two- or three-dimensional architecture. This processing approach leads to dense composites where matrix microstructure and composition can be tailored for optimum properties. It has much lower processing cost (less than 50 percent) in comparison to other approaches to fabricating silicon-carbide-based composites. The photograph shows the various AFReCC components. Thermomechanical and thermochemical characterization of these composites under the hostile environments that will be encountered in engine applications is underway.
Advanced ceramics and fiber-reinforced ceramic matrix composites with high strength and toughness, good thermal conductivity, thermal shock resistance, and oxidation resistance are needed for high-temperature structural applications in advanced high-efficiency and high-performance engines, space propulsion components, and land-based systems. The engineering designs of these systems require the manufacturing of large parts with complex shapes, which are either quite expensive or impossible to fabricate. In many instances, it is more economical to build complex shapes by joining together simple geometrical shapes. Thus, joining has been recognized as an enabling technology for the successful utilization of advanced ceramics and fiber-reinforced composite components in high-temperature applications. However, such joints must retain their structural integrity at high temperatures and must have mechanical strength and environmental stability comparable to those of the bulk materials. In addition, the joining technique should be robust, practical, and reliable. ARCJoinT, which is based on the reaction-forming approach, is unique in terms of producing joints with tailorable microstructures. The formation of joints by this approach is attractive since the thermomechanical properties of the joint interlayer can be tailored to be very close to those of the base materials. In addition, high-temperature fixturing is not needed to hold the parts at the infiltration temperature. The joining process begins with the application of a carbonaceous mixture in the joint area, holding the items to be joined in a fixture, and curing at 110 to 120 C for 10 to 20 min. This step fastens the pieces together. Then, silicon or a silicon alloy in tape, paste, or slurry form is applied around the joint region and heated to 1250 to 1425 C (depending on the type of infiltrant) for 10 to 15 min. The molten silicon or silicon-refractory metal alloy reacts with carbon to form silicon carbide with controllable amounts of silicon and other phases as determined by the alloy composition. Joint thickness can be readily controlled through adjustments of the properties of the carbonaceous paste and the applied fixturing force. The photograph shows various shapes of silicon-carbide-based ceramics and fiberreinforced composites that have been joined using ARCJoinT. Thermomechanical and thermochemical characterization of joints is underway for a wide variety of silicon-carbidebased advanced ceramics and fiber-reinforced composites under the hostile environments that will be encountered in engine applications. ARCJoinT, which was developed by researchers at the NASA Glenn Research Center at Lewis Field, received R&D Magazine's prestigious R&D 100 Award in 1999.
An approach developed at the NASA Glenn Research Center for extending the shelf life of PMR polyimide solutions and prepregs received an R&D 100 Award this year. PMR polyimides, in particular PMR-15, have become attractive materials for a variety of aerospace applications because of their outstanding high-temperature stability and performance. PMR-15 can be used in components with exposures to temperatures as high as 290 C, which leads to substantial reductions in weight, as much as 30 percent over metal components. PMR-15 composites are used widely in aerospace applications ranging from ducts and external components in aircraft engines to an engine access door for the Space Shuttle Main Engine. A major barrier to more widespread use of these materials is high component costs. Recent efforts at Glenn have addressed the various factors that contribute to these costs in an attempt to more fully utilize these lightweight, high-temperature materials.
We are honored to recognize the many years of service our colleague Dr. Richard C. Greenwood has provided the community with the Meteoritical Society’s Service Award. Richard’s myriad efforts include his extensive work in education and public outreach, his service to the Meteoritical Society and the broader scientific community, his extensive classification and curation of extraterrestrial samples for research, his committed student mentorship, and his exceptional support of other’s research.
Millions of Americans have experienced the benefits of transitioning to solar, such as money saved on electricity bills and reduced environmental impact. However, many households have been overlooked and left out of this energy transition due to limited funds, low credit scores, language barriers, or lack of solar adoption from neighbors and other community members. Leading organizations have recognized this gap in communications and have started to target more diverse audiences in their solar marketing campaigns. This project outlines three years of American-Made prize funding, recognizing solar industry communications campaigns that demonstrate excellence in strategic, effective, and meaningful communication to diverse audiences across digital, video, marketing, mobile, print, social media, and more.
Patient-based research plays a key role in probing basic visual mechanisms. Less-well recognized is the role of patient-based retinal imaging and visual function studies in elucidating disease mechanisms, which are accelerated by advances in imaging and function techniques and are most powerful when combined with the results from histology and animal models. A patient's visual complaints can be one key to patient management, but human data are also key to understanding disease mechanisms. Unfortunately, pathological changes can be difficult to detect. Before advanced retinal imaging, the measurement of visual function indicated the presence of pathological changes that were undetectable with existing clinical examination. Over the past few decades, advances in retinal imaging have increasingly revealed the unseen. This has led to great strides in the management of many diseases, particularly diabetic retinopathy and macular edema, and age-related macular degeneration. It is likely widely accepted that patient-based research, as in clinical trials, led to such positive outcomes. Both visual function measures and advanced retinal imaging have clearly demonstrated differences among retinal diseases. Contrary to initial thinking, sight-threatening damage in diabetes occurs to the outer retina and not only to the inner retina. This has been clearly indicated in patient results but has only gradually entered the clinical classifications and understanding of disease etiology. There is strikingly different pathophysiology for age-related macular degeneration compared with photoreceptor and retinal pigment epithelial genetic defects, yet research models and even some treatments confuse these. It is important to recognize the role that patient-based research plays in probing basic visual mechanisms and elucidating disease mechanisms, combining these findings with the concepts from histology and animal models. Thus, this article combines sample instrumentation from my laboratory and progress in the fields of retinal imaging and visual function.
In many mountain watersheds of the world, seasonal snowpacks play an important role as natural reservoirs of water. Seasonal snowpacks accumulate water during cold, wet winter months that subsequently melts. Downstream communities depend on water from melting seasonal snowpacks to support agricultural, industrial, and municipal water needs. Rapidly melting snowpacks can also present a flooding hazard, particularly if snowpacks melt at rates faster than anticipated and where adequate reservoir capacity is unavailable to buffer river flows associated with melt. The spatial and temporal dynamics of snow accumulation and melt also play an important role in supporting upland ecosystems in mountain landscapes. Snowmelt provides soil moisture that enable terrestrial ecosystem productivity and exert control on soil microorganisms that play important roles in global carbon cycles. Climate warming is gradually decreasing the amount of precipitation in mountain watersheds arriving as snow, presenting potentially profound disruptions to mountain ecosystems, as well as downstream delivery of water. The overarching goal of this project was to understand how interactions between the near-surface atmosphere and surface topography control the input, accumulation, retention, and release of water from mountain snowpacks. Over a 5-year period, this project pursued an approach combining high-resolution regional climate modeling, satellite and airborne remote sensing data, and ground-based observations to develop and analyze benchmark datasets to address overarching science questions and hypotheses. Key products include a continuous, long-term, high spatiotemporal resolution (1 km/1 hr) dataset characterizing key climate variables in the Upper Colorado River Basin. The dataset included historical estimates of precipitation, temperature, humidity, solar and longwave radiation, and wind speeds. Additionally, the project developed a 20+ year long, 30 m spatial, daily temporal multi-sensor dataset characterizing snow presence/absence in the East/Taylor River watersheds in the Central Rocky Mountains of Colorado. The project supported training of 1 postdoctoral scholar, 1 Ph.D. student, and 1 M.S. student.
The focus of this grant was on molecular magnetic materials for information storage and quantum computing. We have been developing robust, first-principle methods for computing relevant electronic and magnetic properties of molecular building blocks (SMMs) of novel magnetic materials and quantum computers. These tools enable theoretical modeling of SMMs’ behavior, facilitating the interpretation of experimental studies and aiding the design of novel magnetic materials. Our strategy is based on the spin-flip (SF) approach, which extends the hierarchy of black-box single-reference methods to strongly correlated systems. Specifically, we developed general scalable algorithms and computer codes for calculating molecular properties, with an emphasis on spin-related properties, such as zero-field splittings, hyperfine couplings, and g-tensors. While our primary focus was on SF wave functions and SF-TDDFT, the underlying theory and computer codes were formulated using reduced density matrices, such that these tools are applicable to a broader class of methods. To extend the scope of applicability of wave-function-based SF methods to larger systems, we developed reduced-scaling approaches for the equation-of-motion coupled-cluster (EOM-CC) methods and continue developing libtensor (our open-source general tensor contraction library for many-body methods). We carried out extensive benchmarks and also carried out several applications.
Final technical report
Autonomous operations and maintenance (O&M) by robots has been identified as a key technology to facilitate both the safe operation, and reduced operational costs associated with future nuclear reactors. Radiation and thermal environments, particularly associated with molten salt reactor designs, excludes the use of human proximity and so there is a need to train robots for tasks that have not yet been fully identified, or for accidents that may occur in the future. This program sought to develop a generic methodology that could be applied to train ‘any’ robot, to perform ‘any’ task, through the use of machine learning (ML) training performed in a virtual reality (VR) environment that simulates the physically perceived task(s). The VR environment allows us to construct ‘any’ future task and the ML approach, which included reinforcement learning (RL), allowed us to generate extensive data sets that can be used to establish control algorithms to thereby control the physical robot in the physical environment.
The overarching goal of this project is to understand how the phase coherence of phonons and the interaction of phonons with other microscopic degrees of freedom in nanomaterials, such as 2D materials, can affect the energy transport properties and eventually lead to control of energy transport by manipulating phonon interference and phonon scatterings. On the computational side, we are developing and applying first-principles methods to study emerging phonon properties in nanomaterials, including coherent phonons, resonant bonding and gate-tunable phonon-electron scatterings, which hold the promise of enabling significant tunability of energy transport processes with external fields for a wide range of applications. On the experimental side, we are developing ultrafast transient grating spectroscopy and scanning ultrafast electron microscopy (SUEM) to directly probe the coherent phonon transport and phonon-electron interaction processes in nanomaterials with high combined spatial-temporal resolutions. This program will not only provide new insights into the microscopic transport and interaction processes of fundamental energy carriers, but also open new venue towards energy-relevant applications such as thermal switches and coherent energy harvesters.
Presentation of NETL's applied R&D on unconventional critical minerals at the 2024 Ramaco Research Rodeo.
The aim of this program was to gain a fundamental understanding of the behavior of various guest molecules in nano-confined environments, such as metal organic frameworks (MOFs), using a combination of novel synthesis, ab initio modeling, and in situ characterization. Through this project, we developed a concise understanding of the mechanisms that control adsorption/desorption of gaseous molecules and their mixtures, leading to design/synthesis guidelines for MOFs with desired functionality. We further developed methods to disentangle kinetic from thermodynamic effects during adsorption, as well as to characterize the interactions at play. In the first funding cycle, the focus was on the unambiguously characterization of co-adsorption and diffusion of gasses/vapors and their mixtures. In the second funding cycle, the focus was on characterizing the effects of the nano-confinement on the kinetics and thermodynamics of adsorption processes inside MOFs, again with an emphasis on mixtures of gasses and vapors. The nano-confinement can tip the thermodynamic vs. kinetic balance, and current understanding and theory based on single-component analysis can lead to incorrect predictions for mixtures. This is of particular interest in real-world applications, where gasses/vapors are typically mixed, contain impurities, or are often exposed to humid conditions. Our main findings were: (i) within confined environments the adsorption behavior of mixed gasses/vapors can be drastically different from the “sum” of the corresponding single phases; (ii) co-adsorption is often competitive and detrimental to performance, but it can also be cooperative and beneficial; (iii) in some co-adsorbed gasses/vapors, molecules that are strongly bound in the single-component phase can be replaced by molecules that are nominally weaker bound (molecular exchange) due to guest-guest interactions that lower the kinetic barriers and favor the final adsorption state; (iv) kinetic and thermodynamic effects can be precisely controlled through pore-size engineering and synthesis; and, (v) kinetic effects can be identified and disentangled from thermodynamic effects during adsorption through a series of sequential and simultaneous gas loading measurements. The short-term goal of this program was the controlling and understanding of common MOF systems in real-world situations where gasses/vapors are mixed, which will have an important impact on industrial processes and applications from gas storage and sequestration to catalysis and sensors. The long-term goals include the development of theoretical and experimental methods for gaining a fundamental understanding of adsorption/reaction processes within MOFs, as well as new guidelines for synthesizing MOFs with tailored physical and chemical properties.
This project aimed to develop a suite of novel technologies targeted at detecting individual barium ions produced in neutrinoless double beta decays of 136 Xe, as part of the NEXT program of gaseous xenon detectors. We realized novel molecules which could sense Ba 2+ ions in dry conditions; new microscopy techniques operable in dry noble gases, including the required operating conditions of xenon at 10 bar pressure; and new radiofrequency ion transport methods (developed both theoretically and experimentally) that can transport ions in dense xenon gas. Together, these developments represent a major advance toward a background-free neutrinoless double beta decay experiment based on single molecule fluorescence imaging of Ba 2+ daughter ions.
This project will develop a high efficiency solar cell using high-resistivity, high-lifetime multi-crystalline p-type kerfless Direct Wafer (DW) Product developed by CubicPV. NREL developed technology for passivating contacts will be utilized under this CRADA.