ABSTRACT
By mixing ionic liquids (ILs), it is possible to fine-tune their bulk and interfacial structure. This alters their physical properties and solvation behavior and is a simple way to prepare a collection of ILs whose properties can be tuned to optimize a specific application. In this study, mixtures of perfluorinated and alkylated ILs have been prepared, and links between composition, properties, and nanostructure have been investigated. These different classes of ILs vary substantially in the flexibility and polarizability of their chains. Thus, a range of useful structural and physical property variations are accessible through mixing that will expand the library of IL mixtures available in an area that to this point has received relatively little attention. In the experiments presented herein, the physical properties and bulk structure of mixtures of 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide [C8MIM][Tf2N] and 1-(1H,1H,2H,2H-perfluorooctyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C8MIM-F13][Tf2N] have been prepared. The bulk liquid structure was investigated using a combination of small-angle X-ray and neutron scattering (SAXS and SANS, respectively) experiments in combination with atomistic molecular dynamics simulations and the measurement of density and viscosity. We observed that the addition of [C8MIM-F13][Tf2N] to [C8MIM][Tf2N] causes changes in the nanostructure of the IL mixtures that are dependent on composition so that variation in the characteristic short-range correlations is observed as a function of composition. Thus, while the length scales associated with the apolar regions (polar non-polar peakâPNPP) increase with the proportion of [C8MIM-F13][Tf2N] in the mixtures, perhaps surprisingly given the greater volume of the fluorocarbon chains, the length scale of the charge-ordering peak decreases. Interestingly, consideration of the contact peak shows that its origins are both in the direct anion···cation contact length scale and the nature (and hence volume) of the chains appended to the imidazolium cation.
ABSTRACT
OBJECTIVE: The present study integrates several distinct lines of jury decision-making research by examining how the racial identities of the defendant and an informant witness interact in a federal drug conspiracy trial scenario and by assessing whether jurors' individual racial identity and jury group racial composition influence their judgments. HYPOTHESES: We predicted that jurors would be biased against the Black defendant and would be more likely to convict after exposure to a White informant, among other hypotheses. METHOD: We recruited 822 nonstudent jury-eligible participants assigned to 144 jury groups. Each group was assigned to one of four onditions where defendant race (Black or White) and informant race (Black or White) was manipulated. Each group watched a realistic audio-visual trial presentation, then deliberated as a group to render a verdict. RESULTS: Contrary to expectations, the conditions depicting a Black defendant yielded lower conviction rates compared to those with a White defendant-at both the predeliberation individual (odds ratio [OR] = 1.54) and postdeliberation group level (OR = 2.91)-while the informant race did not influence verdict outcomes. We also found that jurors rated the government witnesses as more credible when the defendant was White compared to when he was Black. Credibility ratings and verdict outcomes were also predicted by jurors' own race, although juror race did not interact with the race conditions when predicting verdicts. CONCLUSIONS: Jurors are sensitive to defendant race, and this sensitivity appears to strengthen after deliberation-but in a direction opposite to what was expected. One potential implication of our findings is that juries may operate as a check on system bias by applying greater scrutiny to law enforcement-derived evidence when the defendant is Black. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
