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A five-day discovery-based summer workshop for incoming ninth graders was designed and conducted at the University of Cincinnati (UC). The idea was to have an inquiry-based, research-driven laboratory experience where students were provided with a mentor who encouraged creativity and inquisitiveness. Over a period of three years, 33 students participated in this UC workshop. The students performed a series of experiments and toured and utilized the analytical instrumentation facilities at UC. During the first year, the goal of the workshop was to have the students design their own chemical sensor for anions in water. In subsequent years, the students were given the opportunity to investigate a research question arising from any of the experiments they performed throughout the week. Students were not given explicit instructions for activities. For example, a typical question could have been "Which anion shows luminescence?", but they were not told how to discover this. On the last two days the students were tasked with proposing a question they wished to have answered and developed an experiment to test the hypothesis. At the conclusion of the workshop, each group or individual student presented their results and showed confidence in their work.

With the utilization of nitrophenols in manufacturing various materials and the expansion of industry, nitrophenols have emerged as water pollutants that pose significant risks to both humans and the environment. Therefore, it is imperative to convert nitrophenols into aminophenols, which are less toxic. This conversion process is achieved through the use of noble metal nanoparticles, such as gold, silver, copper, and palladium. The primary challenge with noble metal nanoparticles lies in their accumulation and deactivation, leading to a decrease in catalyst activity. Covalent organic frameworks (COFs) are materials characterized by a crystalline structure, good stability, and high porosity with active sites. These properties make them ideal substrates for noble metal nanoparticles, enhancing catalytic activity. This overview explores various articles that focus on the synthesis of catalysts containing noble metal nanoparticles attached to COFs as substrates to reduce nitrophenols to aminophenols. [ABSTRACT FROM AUTHOR]

Molecular recognition of an aqueous pertechnetate (TcO4–) anion is fundamentally challenging partly due to the charge-diffuse nature of this anion, which hampers design of new technologies for its separation and detection. To address this gap, simple salts of transition metal complexes that undergo a distinct spectroscopic change upon exposure to aqueous anions were explored. The Pt(II) complex [Pt(tpy)Br]SbF6 (tpy = 2,2′;6′,2″-terpyridine) undergoes a dramatic color change and intense luminescence response upon TcO4– uptake due to concomitant enhancement of Pt···Pt interactions. The spectroscopic response was highly selective and quantitative for aqueous TcO4– among other competing anions. Complementary Raman spectroscopy and microscopy techniques, structural determination, and theoretical methods were employed to elucidate the mechanism of this response at the molecular level. [ABSTRACT FROM AUTHOR]

This study explores the vapochromic and vapoluminescent behaviors of [Pt(tpy)Cl]PF 6 host molecules (tpy = 2,2':6',2''-terpyridine) under acetonitrile (CH 3 CN) vapor guest, challenging the conventional view that these phenomena arise solely from direct host-guest interactions. Our findings reveal a cooperative mechanism where mechanochromic surface perturbations prime the Pt(II) host for guest incorporation, leading to initial color and luminescence changes prior to significant structural alterations. While the color transition between the yellow [Pt(tpy)Cl]PF 6 form and the red/orange [Pt(tpy)Cl]PF 6 ·CH 3 CN form is reversible, repeated vapor cycling induces a loss of crystallinity, as indicated by diffraction peak broadening and emission shifts. Scanning electron microscopy analyses show mechanical deformations such as bending and surface pitting, emphasizing the role of vapomechanical stress in altering optical properties. These insights highlight the need for integrated design strategies in developing robust vapochromic materials for gas sensing applications.

Insecticide formulations with safer environmental profiles and limited off-target effects are desirable to manage medical and veterinary pests. Silver nanoparticles are insecticidal against mosquitos, nonbiting midges, and other insects. The biting midge, Culicoides sonorensis Wirth and Jones, is a vector of agriculturally important pathogens in much of the United States, and this study aimed to examine the insecticidal properties of silver nanoparticles in larvae of this species. Mortality of third-instar larvae was assessed daily for 7 days after exposure to concentrations of silver nanoparticles, sorghum polymer particles, and hybrid silver-sorghum polymer particles. Both silver nanoparticles and silver-sorghum polymer particles were insecticidal, but sorghum polymer particles alone did not significantly contribute to larval mortality. Concentrations of 100 mg/liter of silver nanoparticles achieved >50% mortality at day 7, and 200 mg/liter treatments achieved >75% larval mortality within 24 h. The antimicrobial properties of silver nanoparticles were also examined, and culturable bacteria were recovered from larval-rearing media at 200 mg/liter but not at 400 mg/liter of silver nanoparticles. These data suggest that C. sonorensis larval mortality is primarily caused by silver nanoparticle toxicity and not by the reduction of bacteria (i.e., a larval food source). This work describes the first use of silver nanoparticles in C. sonorensis and shows the potential insecticide applications of these nanoparticles against this agricultural pest. The grain-polymer particles also successfully carried insecticidal silver nanoparticles, and their utility in loading diverse compounds could be a novel toxin delivery system for biting midges and similar pests., (Published by Oxford University Press on behalf of Entomological Society of America 2024.)