Rapid Synthesis of Ruthenium-Copper Nanocomposites as High-Performance Bifunctional Electrocatalysts for Electrochemical Water Splitting.

Development of high-performance, low-cost catalysts for electrochemical water splitting is key to sustainable hydrogen production. Herein, ultrafast synthesis of carbon-supported ruthenium-copper (RuCu/C) nanocomposites is reported by magnetic induction heating, where the rapid Joule's heating of RuCl and CuCl at 200 A for 10 s produces Ru-Cl residues-decorated Ru nanocrystals dispersed on a CuCl scaffold, featuring effective Ru to Cu charge transfer. Among the series, the RuCu/C-3 sample exhibits the best activity in 1 m KOH toward both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), with an overpotential of only -23 and +270 mV to reach 10 mA cm, respectively.

Stable Cuprous Hydroxide Nanostructures by Organic Ligand Functionalization.

Copper compounds have been extensively investigated for diverse applications. However, studies of cuprous hydroxide (CuOH) have been scarce due to structural metastability. Herein, a facile, wet-chemistry procedure is reported for the preparation of stable CuOH nanostructures via deliberate functionalization with select organic ligands, such as acetylene and mercapto derivatives.

High-Performance Photocatalytic Reduction of Nitrogen to Ammonia Driven by Oxygen Vacancy and Ferroelectric Polarization Field of SrBi Ti O Nanosheets.

Photo-responsive semiconductors can facilitate nitrogen activation and ammonia production, but the high recombination rate of photogenerated carriers represents a significant barrier. Ferroelectric photocatalysts show great promise in overcoming this challenge. Herein, by adopting a low-temperature hydrothermal procedure with varying concentrations of glyoxal as the reducing agent, oxygen vacancies (Vo) are effectively produced on the surface of ferroelectric SrBi Ti O (SBTO) nanosheets, which leads to a considerable increase in photocatalytic activity toward nitrogen fixation under simulated solar light with an ammonia production rate of 53.

High-Efficiency Photodynamic Antibacterial Activity of NH-MIL-101(Fe)@MoS/ZnO Ternary Composites.

Bacterial infections are a serious threat to human health, and the development of effective antibacterial agents represents a critical solution. In this study, NH-MIL-101(Fe)@MoS/ZnO ternary nanocomposites are successfully prepared by a facile wet-chemistry procedure, where MoS nanosheets are grown onto the MIL-101 scaffold forming a flower-like morphology with ZnO nanoparticles deposited onto the surface. The ternary composites exhibit a remarkable sterilization performance under visible light irradiation toward both Gram-negative and Gram-positive bacteria, eliminating 98.

Caries inhibition of simulated active caries lesions with CO laser irradiation and fluoride.

It has been well established that CO laser irradiation can be used to transform the mineral phase of dental enamel to make it more resistant to acid dissolution. The purpose of this study was to investigate if carbon dioxide laser irradiation and topical fluoride can be used to treat incipient caries lesions to inhibit further progression, i.e.

Use of SWIR dehydration and OCT to assess the complete arrest of simulated incipient caries lesions.

Previous studies have shown that optical coherence tomography (OCT) can be used to show the formation of a transparent surface zone on caries lesions indicative of remineralization. Studies have also shown that monitoring changes in the diffuse reflectivity of caries lesions during drying with air can be used to assess lesion activity and that the largest changes occur at SWIR wavelengths coincident with high water absorption at 1450 and 1950 nm. The purpose of this study was to determine when remineralization has occurred by monitoring changes in SWIR reflectance measurements and OCT images of simulated lesions over an extended time period during exposure to a remineralization solution.

Dehydration imaging of dental fluorosis at 1950 nm.

Dental fluorosis is an increasing problem in the U.S. due to excessive exposure to fluoride from the environment.

High contrast imaging of dental fluorosis in the short wavelength infrared.

Dental fluorosis is an increasing problem due to over exposure to fluoride from the environment. Fluorosis causes hypomineralization of the enamel during tooth development and mild fluorosis is visible as faint white lines on the tooth surface while the most severe fluorosis can result in pitted surfaces. It is difficult to quantify the severity of mild to moderate fluorosis and assessments are limited to subjective visual examinations.

Dynamic SWIR imaging near the 1950-nm water absorption band for caries lesion diagnosis.

Significance: It is not sufficient to detect caries lesions on tooth surfaces; it is also necessary to measure the activity of the lesions to determine if intervention is needed. Changes in the reflectivity of lesion areas during dehydration with forced air at short wavelength infrared (SWIR) wavelengths can be used to assess lesion activity since these changes represent the evaporation dynamics of water from the lesion.

Aim: The aim of this study is to develop new optical methods for assessing lesion activity on tooth surfaces utilizing the strong water absorption band near 1950-nm.

High contrast reflectance imaging at 1950 nm for the assessment of lesion activity on extracted teeth.

Changes in the reflectivity of lesions on the proximal surfaces of extracted human teeth were measured at SWIR wavelengths from 1300-2000 nm as they were dried with air to assess lesion activity. An extended range tungsten-halogen lamp with bandpass filters of varying wavelength (bandwidth) 1300 nm (90), 1460 nm (85), 1535 nm (80), and 1675 nm (90) along with a broadband ASE source centered near the peak of the water-absorption band at 1950-nm were used as light sources and an extended range InGaAs camera (1000-2340 nm) was used to acquire reflected light images as the samples were dried with air. MicroCT images were used as a gold standard for comparison.