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The use of three-dimensional printing in chemistry education has expanded greatly in the past 10 years. The technique has been used to demonstrate a range of concepts including molecular structure, orbitals, and point groups; to produce chemical equipment such as cuvettes and columns; and even to print out mathematical shapes and functions. Here, 3D printing is used to create physical models of two-dimensional NMR spectra and HPLC chromatograms to facilitate student understanding of these challenging concepts. The target audience are undergraduate and postgraduate students as well as university teachers and researchers. Methods to create and print tangible models of the data are presented using the Mathematica and MATLAB programming environments. The models can then be used as useful teaching tools to assist with developing representational competence. The underlying data for the models may be created in-house or obtained from online databases. Instructions to convert the raw data to 3D printable files are provided, and the options for optimizing the resulting files are discussed. These innovative physical models allow students, particularly those who are visual and/or tactile learners, to better understand the complex information presented in multidimensional spectra and chromatograms and enhance student understanding of these forms of data.

Two-dimensional (2D) materials are promising platforms for future nanoelectronic technologies as they provide the building blocks for atomically thin devices, including switches, amplifiers, and oscillators. When 2D materials are layered on top of each other, forming van der Waals heterostructures (vdWHs), they can provide unique properties not possessed by the individual layers. Here we consider the vdWHs HfS2/MoTe2, HfS2/WTe2, 1T-HfS2/WTe2, TiS2/WSe2, TiS2/ZnO, and TiSe2/WTe2 as potential Esaki (or tunnel) diodes that can be incorporated into electronic devices. In this work, the strongly constrained and appropriately normed (SCAN) meta-generalised-gradient approximation (meta-GGA) functional is employed for the structural properties, whereas the Heyd–Scuseria–Ernzerhof (HSE) functional is used for the electronic properties. We establish that the band alignments in these systems form broken-band heterojunctions. We show that the electronic properties of the systems can be effectively modulated by applying lateral strain or an external electric field. Importantly, we demonstrate that the band gap of the vdWHs can be widened by up to 0.65 eV by applying an electric force field of −1 to +1 eV Å−1. This work demonstrates a set of 6 vdWHs with properties suitable for application as 2D Esaki tunnel diodes, 4 of which could be applied as multifunctional devices. These materials not only offer new device properties, but their small dimensions allow for the creation of ultrathin devices. [ABSTRACT FROM AUTHOR]

Liquid metal‐based printing techniques are emerging as an exemplary platform for harvesting non‐layered 2D materials with a thickness down to a few nanometres, leading to an ultra‐large surface‐area‐to‐volume ratio that is ideal for sensing applications. In this work, the synthesis of 2D tin dioxide (SnO2) by exfoliating the surface oxide of molten tin is reported which highlights the enhanced sensing capability of the obtained materials to ammonia (NH3) gas is reported. It is demonstrated that amperometric gas sensors based on liquid metal‐derived 2D SnO2 nanosheets can achieve excellent NH3 sensing performance at low temperature (150 °C) with and without UV light assistance. Detection over a wide range of NH3 concentrations (5–500 ppm) is observed, revealing a limit of detection at the parts per billion (ppb) level. The 2D SnO2 nanosheets also feature excellent cross‐interference performance toward different organic and inorganic gas species, showcasing a high selectivity. Further, ab initio DFT calculations reveal the NH3 adsorption mechanism is dominated by chemisorption with a charge transfer into 2D SnO2 nanosheets. In addition, a proof of concept for prototype flexible ammonia sensors is demonstrated by depositing 2D SnO2 on a polyimide substrate, signifying the high potential of employing liquid metal printed SnO2 for realizing wearable gas sensors. [ABSTRACT FROM AUTHOR]

Mobile technology is increasingly prevalent in higher education. Chemistry-related software applications (apps) on touchscreen computers are emerging as a popular platform in many areas, including in the chemistry classroom. In this work, a new game-based app designed for hand-held and portable touch-controlled devices is presented. Chirality-2 covers multiple aspects of introductory undergraduate organic chemistry. The app allows users to earn chemistry-type medals related to his or her score for each stage, track progress, and post scores and compete with peers on social media. The app is free to download on both the iOS and Android operating systems and aims to help reinforce important chemical concepts necessary for introductory undergraduate chemistry courses worldwide. The target audience includes teachers and students at the final year of high school and introductory undergraduate level.

Using tangible models to help students visualize chemical structures in three dimensions has been a mainstay of chemistry education for many years. Conventional chemistry modeling kits are, however, limited in the types and accuracy of the molecules, bonds and structures they can be used to build. The recent development of 3D printing technology has allowed a much wider variety of molecules to be created for teaching but is not simple to do. Creating the files needed to print molecular structures is often technically difficult and requires the use of multiple software programs, which are not always user-friendly. Not all educators or students have the resources or technical skill to create such files and so are put off trying to use 3D printing in the classroom. Here we demonstrate a simple method to easily generate the files needed for the 3D printing of almost any molecule using the National Institutes of Health Print Exchange server (or simple alternatives). The basic molecule structure may be created in-house or easily sourced online from databases such as UniProt or PubChem. The options for quickly and cheaply printing such structures in a range of materials using online and local stores, as well as in-house 3D printers, are explored and a simple protocol is described. The method brings 3D printing to a wider audience, thus helping to spread its use in chemical pedagogy, and may also be used in self-directed learning exercises by students themselves.

The main goal of the TRacking Aerosol Convection interactions ExpeRiment (TRACER) project was to further understand the role that regional circulations and aerosol loading play in the convective cloud life cycle across the greater Houston, Texas, area. To accomplish this goal, the United States Department of Energy and research partners collaborated to deploy atmospheric observing systems across the region. Cloud and precipitation radars, radiosondes, and air quality sensors captured atmospheric and cloud characteristics. A dense lower-atmospheric dataset was developed using ground-based remote sensors, a tethersonde, and uncrewed aerial systems (UASs). TRACER-UAS is a subproject that deployed two UAS platforms to gather high-resolution observations in the lower atmosphere between 1 June and 30 September 2022. The University of Oklahoma CopterSonde and the University of Colorado Boulder RAAVEN (Robust Autonomous Aerial Vehicle – Endurant Nimble) were flown at two coastal locations between the Gulf of Mexico and Houston. The University of Colorado Boulder RAAVEN gathered measurements of atmospheric thermodynamic state, winds and turbulence, and aerosol size distribution. Meanwhile, the University of Oklahoma CopterSonde system operated on a regular basis to resolve the vertical structure of the thermodynamic and kinematic state. Together, a complementary dataset of over 200 flight hours across 61 d was generated, and data from each platform proved to be in strong agreement. In this paper, the platforms and respective data collection and processing are described. The dataset described herein provides information on boundary layer evolution, the sea breeze circulation, conditions prior to and nearby deep convection, and the vertical structure and evolution of aerosols. The quality-controlled TRACER-UAS observations from the CopterSonde and RAAVEN can be found at 10.5439/1969004 (Lappin, 2023) and 10.5439/1985470 (de Boer, 2023), respectively. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive review of Marfan Syndrome (MFS), covering its epidemiology, etiology, clinical presentations, diagnostics, complications, and treatment modalities. The Ghent II Nosology of MFS criteria are crucial in MFS diagnosis, guiding clinicians in identifying high-risk patients. Nursing implications underscore the importance of screenings, assessments, and close follow-ups to optimize the continuum of care for individuals with MFS. This article provides a comprehensive review of Marfan Syndrome, covering its epidemiology, etiology, clinical presentations, diagnostics, complications, and treatment modalities. [ABSTRACT FROM AUTHOR]

Food allergies are on the rise; the incidence and types of foods implicated have increased worldwide. While peanut allergies are the most well-known, allergies exist to almost all types of foods. This article discusses various types of food allergies along with the most recent prevention and treatment strategies. [ABSTRACT FROM AUTHOR]

The main goal of the TRacking Aerosol Convection interactions ExpeRiment (TRACER) project was to further understand the role that regional circulations and aerosol loading play in the convective cloud life cycle across the greater Houston, Texas area. To accomplish this goal, the United States Department of Energy and research partners collaborated to deploy atmospheric observing systems across the region. Cloud and precipitation radars, radiosondes, and air quality sensors captured atmospheric and cloud characteristics. A dense lower atmospheric dataset was developed using ground-based remote sensors, a tethersonde, and uncrewed aerial systems (UAS). TRACER-UAS is a subproject that deployed two UAS platforms to gather high-resolution observations in the lower atmosphere between 1 June and 30 September 2022. The University of Oklahoma CopterSonde and the University of Colorado Boulder RAAVEN (Robust Autonomous Aerial Vehicle - Endurant Nimble) were flown at two coastal locations between the Gulf of Mexico and Houston. The University of Colorado RAAVEN gathered measurements of atmospheric thermodynamic state, winds and turbulence, and aerosol size distribution. Meanwhile, the University of Oklahoma CopterSonde system operated on a regular basis to resolve the vertical structure of the thermodynamic and kinematic state. Together, a complementary dataset of over 200 flight hours across 61 days was generated, and data from each platform proved to be in strong agreement. In this paper, the platforms and respective data collection and processing are described. The dataset described herein provides information on boundary layer evolution, the sea breeze circulation, conditions prior to and nearby deep convection, and the vertical structure and evolution of aerosols. [ABSTRACT FROM AUTHOR]