Novel AI technology for 4D tracking and physicochemical characterization of inorganic carbonaceous aerosols in air/water.

Organic and inorganic aerosol particles in the atmosphere are significant drivers of climate change and pose risks to human health. Biomass burning and combustion processes are substantial sources of these particles, mainly inorganic carbonaceous aerosols (IC) such as black carbon (BC), carbon nanotubes (CNT), and graphite. Despite their environmental relevance, the physicochemical properties of IC are not well characterized, limiting the accuracy of their impact assessments on the Earth's radiative balance and human health.

Metal-Free Organocatalytic Formylation by CO-Masked Carbene Functionalized Graphene Oxide Nanosheets.

Despite considerable scientific advancements, there is an urgent need for sustainable, cost-effective, and efficient methods for chemically transforming CO into valuable chemicals. A stable heterogeneous platform is presented that incorporates four key innovations: 1) the first Tröger's base (TB) chemistry in solids via selective four-electron reductive functionalization of CO, 2) an effective heterogeneous organocatalyst for the chemoselective formylation of both NH and SH functionalities with CO, 3) a methodology for metal-free heterogeneous S-formylation of bioactive thiols, and 4) a direct covalent immobilization of CO-protected N-heterocyclic carbenes (NHCs) on graphene oxide nanosheets (GONs). The CO-protected catalyst is developed by covalently attaching imidazole (Im) to GONs and functionalizing them with dimethyl carbonate.

Emission of airborne nanoparticles from electric motors of household appliances.

Unlabelled: Nanoparticulate (ultrafine particle) indoor air pollution is an emerging concern. Evidence points to airborne nanoparticles' potential adverse effects, including the impact on blood pressure, the pulmonary and cardiovascular systems, cognitive performance, oxidative stress, allergen sensitization, and inflammation. Nanoparticles originate from various sources.

A HoLDI mass spectrometry platform for airborne nanoplastic detection.

There are no established protocols for nanoplastic detection within complex environmental matrices. Mass spectrometry (MS) analysis of environmental nanoplastics is impeded by methodological constraints. We present a versatile platform evolved from matrix-assisted laser desorption/ionization (MALDI) MS for airborne nano/microplastic research.

Selective reductive conversion of CO to CH-bridged compounds by using a Fe-functionalized graphene oxide-based catalyst.

Anthropogenic climate change drastically affects our planet, with CO being the most critical gaseous driver. Despite the existing carbon dioxide capture and transformation, there is much need for innovative carbon dioxide hydrogenation catalysts with excellent selectivity. Here, we present a fast, effective, and sustainable route for coupling diverse alcohols, amines and amides with CO via heterogenization of a natural metal-based homogeneous catalyst through decorating on functionalized graphene oxide (GO).

Physicochemical properties and their impact on ice nucleation efficiency of respiratory viral RNA and proteins.

Ice nucleation processes in the earth's atmosphere are critical for cloud formation, radiation, precipitation, and climate change. We investigated the physicochemical properties and ice nucleation potential of selected viral aerosols, including their RNA and proteins, using advanced techniques such as scanning-transmission electron microscopy (S/TEM), small angle X-ray scattering (SAXS), particle analyzers, and a peltier chamber. The experiments revealed that RNA particles obtained from MS2 bacteriophage had a mean freezing point of -13.

On the Role of Starchy Grains in Ice Nucleation Processes.

Little is known about the role of starchy food on climate change processes like ice nucleation. Here, we investigate the ice nucleation efficiency (INE) of eight different starchy food materials, namely, corn (CO), potato (PO), barley (BA), brown rice (BR), white rice (WR), oats (OA), wheat (WH), and sweet potato (SP), in immersion freezing mode under mixed-phase cloud conditions. Notably, among all these food materials, PO and BA exhibit the highest ice nucleation efficiency with ice nucleation temperatures as high as -4.

Nanoplastics in Water: Artificial Intelligence-Assisted 4D Physicochemical Characterization and Rapid In Situ Detection.

For the first time, we present a much-needed technology for the in situ and real-time detection of nanoplastics in aquatic systems. We show an artificial intelligence-assisted nanodigital in-line holographic microscopy (AI-assisted nano-DIHM) that automatically classifies nano- and microplastics simultaneously from nonplastic particles within milliseconds in stationary and dynamic natural waters, without sample preparation. AI-assisted nano-DIHM identifies 2 and 1% of waterborne particles as nano/microplastics in Lake Ontario and the Saint Lawrence River, respectively.

In-situ and real-time nano/microplastic coatings and dynamics in water using nano-DIHM: A novel capability for the plastic life cycle research.

A novel nano-digital inline holographic microscope (nano-DIHM) was used to advance in-situ and real-time nano/microplastic physicochemical research, such as particle coatings and dynamic processes in water. Nano-DIHM data provided evidence of distinct coating patterns on nano/microplastic particles by oleic acid, magnetite, and phytoplankton, representing organic, inorganic, and biological coatings widely present in the natural surroundings. A high-resolution scanning transmission electron microscopy confirmed nano-DIHM data, demonstrating its nano/microplastic research capabilities.

Uptake of Hg on TiO, AlO, and FeO Nanoparticles: Importance in Atmospheric Chemical and Physical Processes.

Mineral dust aerosols play an important role in tropospheric chemistry and aerosol-cloud interaction processes. Yet, their interactions with gaseous elemental mercury (Hg) are not currently well understood. Using a coated-wall flow tube (CWFT) reactor, we measured the uptake of Hg on some common components of mineral dust aerosols, including TiO, AlO, and FeO, and the effects of irradiation (dark, visible and UV-A) and relative humidity (<2% to 60%) on the uptake kinetics.

Novel Dynamic Technique, Nano-DIHM, for Rapid Detection of Oil, Heavy Metals, and Biological Spills in Aquatic Systems.

Numerous anthropogenic and natural particle contaminants exist in diverse aquatic systems, with widely unknown environmental fates. We coupled a flow tube with a digital in-line holographic microscopy (nano-DIHM) technique for aquatic matrices, for real-time analysis of particle size, shape, and phase. Nano-DIHM enables 4D tracking of particles in water and their transformations in three-dimensional space.

Black Carbon Particles Physicochemical Real-Time Data Set in a Cold City: Trends of Fall-Winter BC Accumulation and COVID-19.

Black carbon (BC) plays an important role in climate and health sciences. Using the combination of a year real-time BC observation (photoacoustic extinctiometer) and data for PM and selected co-pollutants, we herein show that annual BC Mass concentration has a bi-modal distribution, in a cold-climate city of Montreal. In addition to the summer peak, a winter BC peak was observed (up to 0.

Advancing the science of dynamic airborne nanosized particles using Nano-DIHM.

In situ and real-time characterization of aerosols is vital to several fundamental and applied research domains including atmospheric chemistry, air quality monitoring, or climate change studies. To date, digital holographic microscopy is commonly used to characterize dynamic nanosized particles, but optical traps are required. In this study, a novel integrated digital in-line holographic microscope coupled with a flow tube (Nano-DIHM) is demonstrated to characterize particle phase, shape, morphology, 4D dynamic trajectories, and 3D dimensions of airborne particles ranging from the nanoscale to the microscale.

Advances in Ultra-Trace Analytical Capability for Micro/Nanoplastics and Water-Soluble Polymers in the Environment: Fresh Falling Urban Snow.

Discarded micro/nano-plastic inputs into the environment are emerging global concerns. Yet the quantification of micro/nanoplastics in complex environmental matrices is still a major challenge, notably for soluble ones. We herein develop in-laboratory built nanostructures (zinc oxide, titanium oxide and cobalt) coupled to mass spectrometry techniques, for picogram quantification of micro/nanoplastics in water and snow matrices, without sample pre-treatment.

Air quality standards for the concentration of particulate matter 2.5, global descriptive analysis.

Objective: To compare ambient air quality standards for the mass concentration of aerosol particles smaller than approximately 2.5 μm (PM) and exposure to these particles in national and regional jurisdictions worldwide.

Methods: We did a review of government documents and literature on air quality standards.

Influence of Al(III) and Sb(V) on the transformation of ferrihydrite nanoparticles: Interaction among ferrihydrite, coprecipitated Al(III) and Sb(V).

Ferrihydrite is ubiquitous in natural environments and is usually co-precipitated with impure ions and toxic contaminants like Al(III) and Sb(V) during the neutralization process of acid mine drainage. However, little is known about the dynamic interactions among ferrihydrite, Al(III) and Sb(V). In this study, the influence of coprecipitated Al(III) and Sb(V) on the transformation of ferrihydrite was investigated.

Simultaneous extraction and fractionation of petroleum biomarkers from tar balls and crude oils using a two-step sequential supercritical fluid extraction.

In this study a novel sustainable method based on supercritical fluid extraction (SFE) method was developed for simultaneous extraction and fractionation of petroleum biomarkers. We herein proposed a two-step supercritical fluid extraction method for crude oil and tar ball to separate the petroleum biomarkers into aliphatic and aromatic fractions. In the first step, pure scCO was used, while scCO modified was used as a solvent in the subsequent step.

Correction to: Development of methodology to generate, measure and characterize the chemical composition of oxidized mercury nanoparticles.

The authors would like to call the reader's attention to the fact that, unfortunately, there was an unintentional oversight regarding the funding information in this manuscript; please find the correct information below.

Supercritical fluid extraction followed by supramolecular solvent microextraction as a fast and efficient preconcentration method for determination of polycyclic aromatic hydrocarbons in apple peels.

In this work, reverse micelle-based supramolecular solvent microextraction method coupled with supercritical fluid extraction and used for determining trace amounts of polycyclic aromatic hydrocarbons in apple peels. The extract was analyzed by high-performance liquid chromatography equipped with a fluorescence detector. Coupling supramolecular solvent microextraction with supercritical fluid extraction method, resolve low preconcentration factor of supercritical fluid extraction method, improved limit of detection of polycyclic aromatic hydrocarbons and allow the use of supramolecular solvent microextraction in solid matrices.

Development of methodology to generate, measure, and characterize the chemical composition of oxidized mercury nanoparticles.

The phase of oxidized mercury is critical in the fate, transformation, and bioavailability of mercury species in Earth's ecosystem. There is now evidence that what is measured as gaseous oxidized mercury (GOM) is not only gaseous but also consists of airborne nanoparticles with distinct physicochemical properties. Herein, we present the development of the first method for the consistent and reproducible generation of oxidized mercury nano- and sub-micron particles (~ 5 to 400 nm).

Natural Kaolin: Sustainable Technology for the Instantaneous and Energy-Neutral Recycling of Anthropogenic Mercury Emissions.

Kaolin, a natural and inexpensive clay mineral, is ubiquitous in soil, dirt, and airborne particles. Amongst four commonly available clay minerals, kaolin, as a result of its layered structure, is the most efficient natural gaseous Hg adsorbent to date (Langmuir maximum adsorption capacity Q =574.08 μg g and Freundlich Q =756.

Novel Technology for the Removal of Brilliant Green from Water: Influence of Post-Oxidation, Environmental Conditions, and Capping.

Chemical dyes are used in a wide range of anthropogenic activities and are generally not biodegradable. Hence, sustainable recycling processes are needed to avoid their accumulation in the environment. A one-step synthesis of Fe-maghemite (Fe-MM) for facile, instantaneous, cost-effective, sustainable, and efficient removal of brilliant green (BG) dye from water has been reported here.

The Existence of Airborne Mercury Nanoparticles.

Mercury is an important global toxic contaminant of concern that causes cognitive and neuromuscular damage in humans. It is ubiquitous in the environment and can travel in the air, in water, or adsorb to soils, snow, ice and sediment. Two significant factors that influence the fate of atmospheric mercury, its introduction to aquatic and terrestrial environments, and its bioaccumulation and biomagnification in biotic systems are the chemical species or forms that mercury exists as (elemental, oxidized or organic) and its physical phase (solid, liquid/aqueous, or gaseous).

Diversity of metals and metal-interactive bacterial populations in different types of Arctic snow and frost flowers: Implications on snow freeze-melt processes in a changing climate.

Arctic snow has been shown to be a reactive interface for key physical, chemical, and microbiological processes, affecting the Arctic's oxidation, biodiversity, radiation, and climate. To explore the potential links between snow-borne metal contaminants and metal-interactive bacteria, to freezing/melting processes, we performed concurrent chemical characterization, genomic, and morphological analysis of five different Arctic snowpack (accumulated, blowing, fresh falling, surface hoar, and wind pack snow) and frost flower in Utqiaġvik (Barrow), Alaska, using Montreal urban snow as reference. Several complementary analytical techniques, including triple quad ICP-MS/MS along with various chromatography techniques, thermal ionization mass spectrometer (TIMS), high-resolution transition electron microscopy with electron dispersive X-ray spectroscopy (HR-TEM/EDS), and next generation sequencing (NGS), were deployed.