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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Advances in Desiccant Wheels for Dehumidification, VOC Mitigation, and CO 2 Removal for Energy-Efficient IAQ Management

Humidity control is pivotal to maintain occupant thermal comfort and suppress mold growth in indoor environments. Furthermore, poor indoor air quality (IAQ) due to the presence of volatile organic compounds (VOCs) and high concentrations (>1,000 ppm) of CO 2 can cause health issues and negatively affect cognitive performance. Therefore, providing high-quality indoor air has gained significant attention over the past decade. Conventional cooling coil and filter-based HVAC systems have limited capability to meet the augmented demand for occupant thermal comfort and high indoor air quality. Moreover, modern buildings are increasingly airtight to save energy, and increasing ventilation to mitigate VOC and CO 2 concentration is discouraged. Separate sensible and latent cooling technology using a rotary desiccant wheel presents a promising solution in this respect. Because of the development of desiccant materials with high water vapor, VOC, and CO 2 uptake, desiccant wheels can be used as an integrated technology option for IAQ management. Here, to promote desiccant wheel use for energy-efficient management of IAQ in buildings, this article reviews recent advancements in using desiccant wheels for dehumidification, VOC mitigation, and CO 2 capture from outdoor air. Finally, the article presents the authors’ perspective by summarizing the key research gaps in the field and discussing the future direction of research to address these gaps from two different aspects, namely, suitable adsorbent material development and desiccant wheel design.

CO2 capture↗
DOE OSTI2013

Anisotropic magnetization and resistivity of single crystalline RNi1-xBi2±y (R=La–Nd, Sm, Gd–Dy)

We present a detailed study of RNi1-xBi2±y (R = La–Nd, Sm, Gd–Dy) single crystals by measurements of stoichiometry and temperature dependent magnetic susceptibility, magnetization, and electrical resistivity. This series forms with partial Ni occupancy, 0.72 ≤ (1-x) ≤ 0.84, as well as a variable Bi occupancy, 1.76 ≤ (2±y) ≤ 2.14. For R = Ce–Nd, Gd–Dy, the RNi1-xBi2±y compounds show local-moment like behavior and order antiferromagnetically at low temperatures. Determination of anisotropies as well as antiferromagnetic ordering temperatures for RNi1-xBi2±y (R = Ce–Nd, Sm, Gd–Dy) have been made. Crystalline samples from this family exhibit minority, second phase superconductivity at low temperatures, which can be associated with Ni–Bi and Bi contamination. No evidence of bulk superconductivity has been observed.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Crystal structure of the $τ_{11}$ Al 4 Fe 1.7 Si phase from neutron diffraction and ab initio calculations

The intermetallic τ 11 Al 4 Fe 1.7 Si phase is of interest for high-temperature structural application due to its combination of low density and high strength. We determine the crystal structure of the τ 11 phase through a combination of powder neutron diffraction and density functional theory calculations. Using Pawley and Rietveld refinements of the neutron diffraction data provides an initial crystal structure model. Since Al and Si have nearly identical neutron scattering lengths, we use density-functional calculations to determine their preferred site occupations. The τ 11 phase exhibits a hexagonal crystal structure with space group P6 3 /mmc and lattice parameters of a = 7.478 Å and c = 7.472 Å. The structure comprises five Wyckoff positions; Al occupies the 6h and 12k sites, Fe the 2a and 6h sites, and Si the 2a sites. Here we observe site disorder and partial occupancies on all sites with a large fraction of 80% Fe vacancies on the 2d sites, indicating an entropic stabilization of the τ 11 phase at high temperature.

36 MATERIALS SCIENCE↗
DOE OSTI2014

First-principles study of the stability and migration of Kr, I and Xe in ZrO2

The stability and migration of Kr, I and Xe in bulk ZrO2 and on the ZrO2 (1 1 1) surface have been studied by standard density functional theory (DFT) and the DFT-D2 method that corrects for the van der Waals interaction. Both methods show that Kr and Xe prefer to incorporate in the bulk phase rather than adsorb on the surface, and Xe is very mobile in the bulk state. For Kr and Xe adsorption on the surface, van der Waals interaction dominates, causing the weak interaction between the adsorbate and substrate. Iodine is found to have comparable stability in both phases and forms I O bonds with strong covalency. It exhibits higher mobility on the surface than in the bulk ZrO2, and diffusion from bulk-like state to surface state is an exothermic process. The fission product behavior in ZrO2 is shown to be a complicated synergetic effect of fission product atomic size, electron negativity, occupation site and phase structure of the host.

Xiao, Haiyan↗
DOE OSTI2021

A density functional theory and neutron diffraction study of the ambient condition properties of sub-stoichiometric yttrium hydride

Several mechanical and thermophysical properties are required as a function of non-stoichiometry for the successful implementation of YH 2-x for nuclear reactor moderator applications. Density functional theory calculations, in combination with neutron diffraction experiments, were used to study the structural and mechanical properties of YH 2-x . Point defect analysis indicated H occupation primarily at the tetrahedral site within an fcc Y sub-lattice, confirming a fluorite YH 2 structure. The small positive formation energy for H vacancies under Y-rich conditions predicted that hypo-stoichiometry is accommodated by Y+YH 2 at ambient conditions and by H vacancies in the YH 2-x single phase that is relevant to high temperatures. Neutron diffraction studies were used to confirm both the occupation of H on tetrahedral sites and the near-stoichiometric composition of the hydride phase in the two-phase Y+YH 2 region of the phase diagram that dominates at room temperature. Energy minimized special-quasirandom-structures of H vacancies were used to calculate lattice parameters, elastic constants, and several other properties as a function of composition for the single phase YH 2-x . The lattice parameter of YH 2-x decreased by only 0.004 Å with increasing H/Y for the range 1.31 ≤ H / Y ≤ 2.0 indicating a negligible effect on lattice parameters due to vacancy formation. In the two-phase region, however, calculations predicted the density of z Y + ( 1 - z ) Y H 2 - x to increase with decreasing H/Y at lower temperatures due to the increased fraction of high-density Y metal. Additionally, for the high temperature single phase, decreasing H/Y reduced the density as a consequence of the lattice expansion associated with vacancy formation. All elastic constants and moduli increased with increasing hydrogen content in single-phase YH 2-x .

36 MATERIALS SCIENCE↗
DOE OSTI2023

Evaluation of thermostat location for multizone commercial building performance

In multi-zone buildings, it is often found that a single shared thermostat controls more than one conditioned zones. Although these shared zones are supposed to have similar thermal needs (e.g., cooling and heating load), in reality, they are not mainly due to different orientations, sizes of windows, occupancy, space types, etc. This can cause unnecessary energy waste or thermal discomfort for the occupants. How to quantify this impact in multizone buildings remains a research gap. Therefore, this study aims to evaluate the impact of different sensor (i.e., thermostat) locations for multizone commercial buildings through a comprehensive modeling study. Here, two different scenarios for the sensor locations were selected to evaluate the impact in terms of energy and thermal comfort. The scenario (1) is that one to five sensors distributed among the five zones, but the sensor readings from selected zones will be used for no-sensor zones, which is no-mean sensor scenario. The scenario (2) is that one to five sensors distributed among the five zones, but the average temperature from the shared zones will be used for each of the shared zones, which is a mean sensor scenario. The uncertainty analysis was performed for different sensor location scenarios.(a)The major findings from an energy perspective, for scenario (1), the differences of cooling energy go as high as 17% more or 12% less, compared with the baseline. For heating energy consumption, the discrepancies go as high as 51% more or 52% less, compared with baseline. For site energy consumption, the discrepancies go as high as 3.2% more or 3.2% less, compared with baseline. For fan energy consumption, the discrepancies go as high as 3.2% more or as low as 1.0% less, compared with baseline. For scenario (2), the discrepancies of cooling energy go as high as 3% more, or 0.5% less, compared with the baseline. For heating energy consumption, the discrepancies, are go as high as 10.1% more or as low as 3.0% less, compared with baseline. For site energy consumption, the discrepancies go as high as 1.3% more or 0.3% less, compared with baseline. For fan energy consumption, the discrepancies go as high as 3.1% more or as low as 1.0% less, compared with baseline.(b) In terms of the indoor thermal comfort, for the no-mean-sensor scenarios, the discrepancies of unmet hours for cooling mode can be as high as 1,200 h, compared with the baseline. The discrepancies of unmet hours for heating mode can be as high as 740 h, compared with the baseline. For the mean-sensor scenarios, the discrepancies of unmet hours for cooling mode can be as high as 750 h, compared with the baseline. The discrepancies of unmet hours for heating mode can be as high as 50 h, compared with the baseline.

42 ENGINEERING↗
DOE OSTI2014

Structural study of Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} and optical spectroscopy of the Eu{sup 3+} dopant ion

The new rare earth-based germanate compound Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} (orthorhombic (Pnma) crystal structure), has been characterized and investigated for the first time, using synchrotron powder X-ray diffraction. From Rietveld refinement calculations on the collected powder pattern we observe an inhomogeneous distribution of the two available cationic sites by Gd{sup 3+} and Ca{sup 2+} ions. In particular, the former prefers the occupation (67.5%) of the site with 8-fold coordination. In addition, we observed a not negligible degree of distortion of the Ge{sub 2}O{sub 7}{sup 6−} unit. Finally, luminescence spectra and decay curves of Eu{sup 3+} doped Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} were measured and analysed taking into account the structural features of the host. The results reveal that this material shows strong red luminescence upon excitation in the region where blue LEDs emit (470 nm). - Graphical abstract: The structural study on Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} exploiting synchrotron X-ray diffraction, allows us to determine the detailed geometry of the metal coordination polyhedra, which is closely related to the emission luminescence spectroscopy of the Eu{sup 3+} dopant ion introduced as impurity in this host. - Highlights: • The crystal structure of the Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9} was determined. • Gd{sup 3+} ion is distributed on two crystal sites with different occupation. • A structural study focused on the metal coordination polyhedra was performed. • Two emitting sites are detected for Eu{sup 3+} dopant ion in Ca{sub 2}Gd{sub 2}Ge{sub 2}O{sub 9}. • Strong red luminescence by excitation in the region where blue LEDs emit was found.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Structures and thermoelectric properties of double-filled (Ca{sub x}Ce{sub 1−x})Fe{sub 4}Sb{sub 12} skutterudites

The structures and thermoelectric properties of the double-filled (Ca{sub x}Ce{sub 1−x})Fe{sub 4}Sb{sub 12} series (x=0, 0.25, 0.5, 0.75, and 1) have been studied using a combined experimental and computational methods. Compounds of (Ca{sub x}Ce{sub 1−x})Fe{sub 4}Sb{sub 12} were obtained only for x=0, 0.5, and 1. Composition with x=0.25 was found to be a mixture of x=0 and 0.5 compounds, and composition with x=0.75 was found to be a mixture of x=1 and 0.5 compounds, respectively. Our conclusions on phase formation are supported by density functional theory (DFT) calculations. In Ca{sub 0.5}Ce{sub 0.5}Fe{sub 4}Sb{sub 12,} Ca substitution in the Ce site of CeFe{sub 4}Sb{sub 12} leads to high hole concentrations, resulting in stronger semimetal transport as compared to CeFe{sub 4}Sb{sub 12}. Ca{sub 0.5}Ce{sub 0.5}Fe{sub 4}Sb{sub 12} yields a slightly higher ZT value than that of CeFe{sub 4}Sb{sub 12}, which is attributed to its lower lattice thermal conductivity. Phonon mode calculations adopting a three-particle bending model suggest that thermal conductivity is reduced upon Ca substitution because of an additional vibration mode which involves both Ca and Ce atoms. - Graphical abstract: Detailed structural information to correlate with thermoelectric properties in a series of double-filled (Ca{sub x}Ce{sub 1−x})Fe{sub 4}Sb{sub 12} skutterudite samples were obtained using synchrotron X-ray diffraction and first principle calculations. - Highlights: • Research focus on phase stability of CaCe double-filled p-type skutterudite. • Stable structure forms for an equiatomic occupancy of the voids by Ca and Ce. • Samples feature two-phase mixtures with variations of filling atoms ratio. • Phase stablility is investigated by DFT total energy calculations. • Sample with Equiatomic occupancy of Ca and Ce show higher ZT.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Probing the limit of magnesium uptake by β-tricalcium phosphate in biphasic mixtures formed from calcium deficient apatites

A series of magnesium doped non-stoichiometric calcium deficient apatites were synthesized through an aqueous precipitation route. The resultant structural changes during heat treatment were investigated by X-ray diffraction, Raman and FT-IR spectroscopy and Rietveld refinement. The results confirmed the formation of biphasic mixtures comprising Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2} and β-Ca{sub 3}(PO{sub 4}){sub 2} after heat treatment at 1000 °C with the preferential occupancy of Mg{sup 2+} at the crystal lattice of β-Ca{sub 3}(PO{sub 4}){sub 2}. The concentration of Mg{sup 2+} uptake in β-Ca{sub 3}(PO{sub 4}){sub 2} is limited till reaching the stoichiometric ratio of (Ca+Mg)/P=1.67 and beyond this stoichiometric value [(Ca+Mg)/P>1.67], Mg{sup 2+} precipitates as Mg(OH){sub 2} and thereafter gets converted to MgO during heat treatment. Any kind of Mg{sup 2+} uptake in the crystal lattice of Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2} is discarded from the investigation. - Highlights: • Aqueous co-precipitation of calcium deficient apatites with excess magnesium (Mg{sup 2+}) additions. • Heat treatments beyond 800 °C results in the formation of biphasic apatite mixtures. • Mg{sup 2+} gets accommodated at the β-Ca{sub 3}(PO{sub 4}){sub 2} lattice of biphasic mixtures. • Mg{sup 2+} additions exceeding stoichiometric value (Ca/P>1.67) results in its formation as MgO. • Mg{sup 2+} occupancy at β-Ca{sub 3}(PO{sub 4}){sub 2} lattice delays its allotropic conversion α-Ca{sub 3}(PO{sub 4}){sub 2} till 1350 °C.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Er{sub 1.33}Pt{sub 3}Ga{sub 8}: A modulated variant of the Er{sub 4}Pt{sub 9}Al{sub 24}-structure type

Single crystals of Er{sub 1.33}Pt{sub 3}Ga{sub 8} were synthesized in a molten Ga flux. Er{sub 1.33}Pt{sub 3}Ga{sub 8} can be considered to be a modulated variant of the Er{sub 4}Pt{sub 9}Al{sub 24}-structure type, where the partial occupancies are ordered. Indeed, the presence of weak satellite reflections indicates a complex organization and distribution of the Er and Ga atoms within the [ErGa] slabs. The structure has been solved based on single crystal X-ray diffraction data in the monoclinic superspace group X2/m(0β0)00 with a commensurate modulated vector q=1/3b*. Precession images also indicate diffusion in the perpendicular direction indicating a partial disorder of this arrangement from layer to layer. In addition, Er{sub 1.33}Pt{sub 3}Ga{sub 8} shows antiferromagnetic ordering at T{sub N}~5 K. - Graphical abstract: A precession image of the hk0 zone showing weak, periodic, unindexed reflections indicating modulation and representation of the commensurate [ErGa] layer showing the waving modulated occupation. - Highlights: • Single crystals of Er{sub 1.33}Pt{sub 3}Ga{sub 8} were grown from gallium flux. • The structure of Er{sub 1.33}Pt{sub 3}Ga{sub 8} is compared to Er{sub 4}Pt{sub 9}Al{sub 24}. • Structure has been solved in the monoclinic superspace group X2/m(0β0)00 with a commensurate modulated vector q=1/3b*.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Microstructural characterization of sulfur-doped Bi{sub 2}Te{sub 3} crystals

In this study, the detailed microstructure of sulfur-doped Bi{sub 2}Te{sub 3} and the distribution of sulfur dopants were investigated using X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD result indicates that the interplanar distances of Bi{sub 2}Te{sub 3} are shortened after introducing sulfur dopants. HRTEM reveals that the unit cell lengths along [001, 100] are decreased as a result of the substitution of Te by smaller S atoms on the anion lattice. XRD and HRTEM analysis suggest that the distortion of the crystal lattice in Bi{sub 2}Te{sub 3} is induced by doping sulfur. High annular angler dark field scanning electron microscopy (HAADF-STEM) image shows obvious contrast variations in the Te atomic columns, indicating that Te sites were unevenly substituted by S dopants. Te columns with least contrast intensity correspond to the preferential occupation sites of S atoms. The replacement of Te atoms by S can be attributed to the evaporated sulfur powder in the gas reaction procedure. The present work is not only contributed to obtain a better understanding of the distribution of sulfur dopants introduced by gas reaction, but also can help explore the structural-property relationship of sulfur-doped Bi{sub 2}Te{sub 3}. - Highlights: • Sulfur-doped Bi{sub 2}Te{sub 3} was synthesized through modified Bridgeman method. • The introduction of S dopants results in shortening the lattice spacing of Bi{sub 2}Te{sub 3}. • HRTEM analysis indicates that S was doped through substituting Te atoms instead of incorporating interstitially. • HAADF-STEM analysis shows that Te columns with least intensity correspond to the preferential occupation sites of S.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Cation distribution in Ni–Cu–Zn nanoferrites from {sup 57}Fe in-field Mössbauer spectra

Highlights: • Occupancy of copper ions at about 20% towards tetrahedral sites. • Distribution is proposed on the basis of % of Fe ions at both A and B sites. • Distribution is checked by estimating the theoretical lattice constant values. - Abstract: The nanoparticles of Ni{sub 1−x}Cu{sub x}Zn{sub 0.35}Fe{sub 2}O{sub 4} were synthesized by sol–gel method using polyvinyl alcohol as a chelating agent. X-ray diffraction patterns of all the samples confirmed the single phase spinel structure. The site occupancy of copper in the nanosized nickel–zinc ferrite spinels was investigated with the help of in-field Mössbauer spectroscopy. Cation distribution for the whole series of compositions was proposed by considering the amounts of iron ions present at both tetrahedral and octahedral interstitial sites in the spinel lattice. Confirmation of the proposed distributions was done by estimating quantitatively the lattice parameters for these compositions and comparing their values with those of the experimentally observed ones.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Neutron diffraction analysis and electrochemical performance of spinel Ni(Mn{sub 2−x}Co{sub x})O{sub 4} as anode materials for lithium ion battery

Highlights: • The reversible capacity and cyclability of Ni(Mn{sub 2−x}Co{sub x})O{sub 4} first increases and then decreases with increasing Co content. • Neutron diffraction and Rielveld refinements are applied to analyze the site occupancies of Mn, Co, O and Ni. • Excessive Co ions in 8a and 16d sites reduce the structure stability leading to poor electrochemical performance. - Abstract: The effects of Co substitution on the structure and electrochemical performances of spinel Ni(Mn{sub 2−x}Co{sub x})O{sub 4} (x = 0, 0.5, and 1.0) have been investigated. With the increase of Co content the lattice parameters decrease owing to the smaller ion radius of Co than Mn. The reversible capacity and cyclability of Ni(Mn{sub 2−x}Co{sub x})O{sub 4} first increase and then decrease with the increase of Co content and NiMn{sub 1.5}Co{sub 0.5}O{sub 4} shows the best electrochemical performance in compared to the other two samples. Neutron diffraction and Rielveld refinement are further applied to analyze the site occupancies of the elements of Mn, Co, O and Ni. A certain amount of Co ions substitution are favorable to enhance the electrochemical performance, but excessive Co ions in 8a and 16d sites reduce the stability of host structure which leads to the poor electrochemical performance.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Remarkable enhancement of La{sub (1-x)}Sm{sub x}CrO{sub 3} nanoperovskite properties: An influence of its doping concentrations

Highlights: • LSCO solid solutions have been synthesized using ball milling method for first time. • Highly polycrystalline single phase LSCO with tolerance factor 0.8 < T > 0.9. • Effective occupancy of dopants onto the respective lattice site is analyzed. • Exhibits dendritic morphology and aggregates with decreasing dopant concentrations. • Synthesized LSCO nanoperovskites exhibit room temperature antiferromagnetism. - Abstract: Rare earth orthochromites of type La{sub (1-x)}Sm{sub x}CrO{sub 3} ((LSCO) x = 0, 0.1, 0.3, 0.5) have been synthesized through solid state reaction. These polycrystalline samples exhibit orthorhombic crystal structure and its corresponding distortion depends on the dopant concentrations. With increasing dopant stoichiometry, the A-O bond length changes resulting in the augmentation of perovskite’s physical properties. The occupancy of relatively less ionic radii dopant influences the decrease in crystallite size, blue shift in emission spectrum and intensification of the phonon characteristic vibrations. The finer particles aggregate to form dendritic morphology and become distinct on Sm/La ratio increments as identified from electron micrographs and atomic force microscopy. Ambient temperature magnetization analysis reveals the enhancement of antiferromagnetic nature upon dopant increments.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Hydrogen isotope trapping in Al-Cu binary alloys

In this study, the trapping mechanisms for hydrogen isotopes in Al–X Cu (0.0 at. % < X < 3.5 at. %) alloys were investigated using thermal desorption spectroscopy (TDS), electrical conductivity, and differential scanning calorimetry. Constant heating rate TDS was used to determine microstructural trap energies and occupancies. In addition to the trapping states in pure Al reported in the literature (interstitial lattice sites, dislocations, and vacancies), a trap site due to Al–Cu intermetallic precipitates is observed. The binding energy of this precipitate trap is (18 ± 3) kJ•mol –1 (0.19 ± 0.03 eV). Typical occupancy of this trap is high; for Al–2.6 at. % Cu (a Cu composition comparable to that in AA2219) charged at 200 °C with 130 MPa D 2 for 68 days, there is ca. there is 3.15×10 –7 mol D bound to the precipitate trap per mol of Al, accounting for a third of the D in the charged sample.

36 MATERIALS SCIENCE↗
DOE OSTI2021

A General Strategy for Batch Development of High-Performance and Cost-Effective Sodium Layered Cathodes

High-performance and low-cost transition metal (TM) layered oxides using earth abundant elements are promising cathodes for Na-ion batteries. However, it is challenging to obtain desired materials because the large Na size, different Na occupations and various layer stacking sequences multiply the complication in determining the structure of a given composition and exacerbate uncertainty to the structure-property correlation. In this work, we use the attainment of desired NaxMnyNiZTM1-y-zO2-based cathode materials as an example to demonstrate a general roadmap for batch development of sodium layered cathodes towards practical applications. A synthesis phase diagram of NaxMnyNi1-yO2 was created for pre-screening and rational selection of the platform material of P2/O3-structured Na0.85Mn0.6Ni0.4O2. Cationic potential was leveraged in elemental substitution to further promote the material structural stability and electrochemical performance. Several cost-effective O3 and P2/O3 hybrid cathode materials have been obtained, all of which demonstrate excellent performance. In particular, the Na0.85Mn0.5Ni0.4Ti0.1O2 delivers a high specific capacity of ~130 mAh/g between 2-4 V and 91% retention after 500 cycles. The work discovers multiple materials as high-performance and cost-effective Na-ion battery cathodes and offers critical guidance to the rational design of future layered cathode materials.

Xiao, Biwei↗
DOE OSTI2021

An overview of data tools for representing and managing building information and performance data

Building information modeling (BIM) has been widely adopted for representing and exchanging building data across disciplines during building design and construction. However, BIM's use in the building operation phase is limited. With the increasing deployment of low-cost sensors and meters, as well as affordable digital storage and computing technologies, growing volumes of data have been collected from buildings, their energy services systems, and occupants. Such data are crucial to help decision makers understand what, how, and when energy is consumed in buildings—a critical step to improving building performance for energy efficiency, demand flexibility, and resilience. However, practical analyses and use of the collected data are very limited due to various reasons, including poor data quality, ad-hoc representation of data, and lack of data science skills. To unlock value from building data, there is a strong need for a toolchain to curate and represent building information and performance data in common standardized terminologies and schemas, to enable interoperability between tools and applications. This study selected and reviewed 24 data tools based on common use cases of data across the building life cycle, from design to construction, commissioning, operation, and retrofits. The selected data tools are grouped into three categories: (1) data dictionary or terminology, (2) data ontology and schemas, and (3) data platforms. The data are grouped into ten typologies covering most types of data collected in buildings. This study resulted in five main findings: (1) most data representation tools can represent their intended data typologies well, such as Green Button for smart meter data and Brick schema for metadata of sensors in buildings and HVAC systems, but none of the tools cover all ten types of data; (2) there is a need for data schemas to represent the basis of design data and metadata of occupant data; (3) standard terminologies such as those defined in BEDES are only adopted in a few data tools; (4) integrating data across various stages in the building life cycle remains a challenge; and (5) most data tools were developed and maintained by different parties for different purposes, their flexibility and interoperability can be improved to support broader use cases. Finally, recommendations for future research on building data tools are provided for the data and buildings community based on the FAIR principles to make data Findable, Accessible, Interoperable, and Reusable.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Role of p53–fibrinolytic system cross-talk in the regulation of quartz-induced lung injury

Silica is the major component of airborne dust generated by wind, manufacturing and/or demolition. Chronic occupational inhalation of silica dust containing crystalline quartz is by far the predominant form of silicosis in humans. Silicosis is a progressive lung disease that typically arises after a very long latency and is a major occupational concern with no known effective treatment. The mechanism of silicosis is not clearly understood. However, silicosis is associated with increased cell death, expression of redox enzymes and pro-fibrotic cytokines and chemokines. Since alveolar epithelial cell (AEC) death and disruption of alveolar fibrinolysis is often associated with both acute and chronic lung injuries, we explored whether p53-mediated changes in the urokinase-type plasminogen activator (uPA) system contributes to silica-induced lung injury. We further sought to determine whether caveolin-1 scaffolding domain peptide (CSP), which inhibits p53 expression, mitigates lung injury associated with exposure to silica. Lung tissues and AECs isolated from wild-type (WT) mice exposed to silica exhibit increased apoptosis, p53 and PAI-1, and suppression of uPA expression. Treatment of WT mice with CSP inhibits PAI-1, restores uPA expression and prevents AEC apoptosis by suppressing p53, which is otherwise induced in mice exposed to silica. The process involves CSP-mediated inhibition of serine-15 phosphorylation of p53 by inhibition of protein phosphatase 2A-C (PP2A-C) interaction with silica-induced caveolin-1 in AECs. These observations suggest that changes in the p53–uPA fibrinolytic system cross-talk contribute to lung injury caused by inhalation of silica dust containing crystalline quartz and is protected by CSP by targeting this pathway. - Highlights: • Chronic exposure to quartz dusts is a major cause of lung injury and silicosis. • The survival of patients with silicosis is bleak due to lack of effective treatments. • This study defines a new role of p53–uPA cross-talk in quartz-induced lung injury. • Targeting the p53–uPA system inhibits ATII cell/lung injury due to quartz exposure.

60 APPLIED LIFE SCIENCES↗