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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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DOE OSTI2018

Analysis for Building Envelopes and Mechanical Systems Using 2012 CBECS Data

This report describes the aggregation and mapping of certain building characteristics data available in the most recent Commercial Building Energy Consumption Survey (CBECS) (DOE EIA 2012) to describe most typical building construction practices. This report provides summary data for potential use in the support of modifications to the Pacific Northwest National Laboratory’s commercial building prototypes used for building energy code analysis. Specifically, this report outlines findings and most typical design choices for certain building envelope and heating, ventilating, and air-conditioning (HVAC) system choices.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2019

Producing Conductive Graphene–Nanocellulose Paper in One-pot

This paper reports a facile one-pot method to produce graphene oxide nanocellulose composite (GNCC) that was subsequently reduced using L-ascorbic acid to form a conductive paper (CP). Cellulose fibers were directly added into the reaction system during graphite exfoliation using sulfuric acid to produce cellulose nano- or microfibrils through acid hydrolysis along with mechancial mixing. FTIR and Raman analyses indicated that reduction using L-ascorbic acid efficiently produced a well-deoxygenated CP with high conductivity of 116.3 ± 1.5 S m{sup −1} at 20% graphene oxide loading. Furthermore, the presence of cellulose nano- or microfibrils improved CP thermal stability with onset degradation T{sub onset} of 319 °C as well as mechanical properties with a specific tensile of 19 N mg{sup −1}. This one-pot method substantially simplified the GNCC production process and has practical significance.

77 NANOSCIENCE AND NANOTECHNOLOGY↗

DOE OSTI2018

Designing antiphase boundaries by atomic control of heterointerfaces

Significance The mechancial and transport properties of every material are intimately coupled to the generation and formation of defects. In many systems, the nucleation process of defects is highly unpredictable due to the multiple coexisting nucleation mechanisms. A strategy to design and manipulate defect nucleation and formation can improve our understanding and in principle lead to the ability to control performance. Here we present a simple approach of designing 2D defects—named antiphase boundaries—using an atomic-controlled high-quality interface. These defects have a well-defined origin, location, and nucleation mechanism. Via advanced synthesis technology, atomically resolved electron microscopy, and theory, we reveal that these defects display distinctive properties such as physical merging and antipolar structural phases to potentially achieve memory devices.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗