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DeSimone, Joseph M.

Publications and source records attributed to DeSimone, Joseph M..

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

The Importance of Chemical Research to the U.S. Economy

Chemistry plays a pivotal role in the strength of the U.S. economy and the advancement of humankind. Chemists' achievements include life-saving pharmaceuticals, advanced energy solutions, improved agricultural productivity, and novel materials used in products from clothing to electronic devices. The many sectors reliant on the U.S. chemical economy account for about 25% of the U.S. GDP and support 4.1 million U.S. jobs. However, a new and evolving chemistry landscape requires changes with regard to funding, training, and a focus on integrating sustainability into manufacturing, product usage, and product disposal. This report identifies strategies and options for research investments that will support U.S. leadership while considering environmental sustainability and developing a diverse chemical economy workforce with equitable opportunities for all chemistry talent. The report recommends that funding agencies and philanthropic organizations who support the chemical sciences fund as large a breadth of fundamental research projects as possible. Chemical industry and their partners at universities, scientific research institutions, and national laboratories should align the objectives of fundamental research to directly assist with new practices toward environmental stewardship, sustainability, and clean energy. Additionally, the report recommends that funding agencies make substantial investment toward education research to enable innovative ways of teaching about emerging concepts, tools and technologies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Difference between approximate and rigorously measured transference numbers in fluorinated electrolytes

The performance of binary electrolytes is governed by three transport properties: conductivity, salt diffusion coefficient, and transference number. Rigorous methods for measuring conductivity and the salt diffusion coefficient are well established and used routinely in the literature. The commonly used methods for measuring transference number are the steady-state current method, t +,id, and pulsed field gradient NMR, t +,NMR . These methods yield the transference number only if the electrolyte is ideal, i.e., the salt dissociates completely into non-interacting anions and cations. In this work, we present a complete set of ion transport properties for mixtures of a functionalized perfluoroether, dimethyl carbonate terminated perfluorinated tetraethylene ether, and lithium bis(fluorosulfonyl)imide (LiFSI). The equations used to determine these properties from experimental data are based on Newman's concentrated solution theory. The concentrated-solution-theory-based transference number, t 0 +, is negative across all salt concentrations, and it increases with increasing salt concentration. In contrast, the ideal transference number, t +,id , is positive across all salt concentrations and it decreases with salt concentration. The NMR-based transference number, t +,NMR , is approximately 0.5, independent of salt concentration. The disparity between the three transference numbers, which indicates the dominance of ion clustering, is resolved by the use of Newman's concentrated solution theory.

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