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Studies often cite climate issues in science, technology, engineering, and mathematics (STEM) employment to explain the lack of diversity by gender and race. Yet, little research directly attends to gender and racial differences in the college experiences, expected family roles, and ideological beliefs about gender that create the racialized “gendered selves” graduates bring to STEM occupations. We examine the experiences and beliefs of graduating chemistry and chemical engineering majors at two U.S. universities, showing where they coalesced into intersectional gender groups whose work and family involvement and desired working conditions substantially differ. Gendered family expectations and workplace beliefs at labor market entry subsequently predict career confidence and family-based limits on job searching, both important factors affecting retention in STEM employment. We find that women at career entry are more likely to have lower confidence and more limits on their job search, though patterns differ by ethnicity. This occurs in part because both male and female graduates who report greater expected family responsibility also report lower confidence and more limits in job searching. Overall, aspirational fulfillment is easier for men whose intersectional gender identities fit the dominant STEM workplace culture, and harder for women and non-white graduates with more flexible gender ideologies and greater anticipated household responsibilities.

Negative permittivity is a key characteristic of the distinctive metamaterials, a novel class of artificial materials with particular electromagnetic properties. Negative permittivity has been realized in metallic structures with special designs, but rarely achieved in polymer nanocomposites. Our recent studies discover that negative permittivity can be attained from randomly distributed carbon nanofiber (CNF) filled poly(vinylidene fluoride) (PVDF) composites over a wide frequency range, and the negative permittivity values are strongly influenced by CNF and PVDF crystalline structures. The effects of CNF on the crystallization of PVDF, and the resultant negative dielectric permittivity of CNF/PVDF composites influenced by crystallization of PVDF and CNF, are investigated. It is revealed that the introduction of CNF not only affects the dielectric permittivity directly, but also causes indirect effects to the dielectric permittivity through influencing the crystallization of PVDF. In particular, due to addition of more CNF, a α‐ to β‐phase transformation in PVDF is found to affect permittivity of the nanocomposites. Furthermore, the permittivity of CNF/PVDF composites are increased considerably (“more negative”) with more CNF, and is affected noticeably by crystalline structures of PVDF. The lowest negative permittivity achieved is −2,500 for the nanocomposite with 5 wt% CNF at 5 kHz.

Solid electrolytes represent a critical component in future batteries that provide higher energy and power densities than the current lithium‐ion batteries. The potential of using ultrathin films is among the best merits of solid electrolytes for considerably reducing the weight and volume of each battery unit, thereby significantly enhancing the energy density. However, it is challenging to fabricate ultrathin membranes of solid electrolytes using the conventional techniques. Here, a new strategy is reported for fabricating sub‐micrometer‐thick membranes of β‐Li₃PS₄solid electrolytes via tiled assembly of shape‐controlled, nanoscale building blocks. This strategy relies on facile, low‐cost, solution‐based chemistry to create membranes with tunable thicknesses. The ultrathin membranes of β‐Li₃PS₄show desirable ionic conductivity and necessary compatibility with metallic lithium anodes. The results of this study also highlight a viable strategy for creating ultrathin, dense solid electrolytes with high ionic conductivities for the next‐generation energy storage and conversion systems.