Bibliometric network analysis has revealed that the widespread distribution of microplastics (MPs) has detrimental effects on marine organisms; however, the combined effects of MPs and climate change (e.g., warming) is not well understood. In this study, Prorocentrum donghaiense, a typical red tide species in the East China Sea, was exposed to different MP concentrations (0, 1, 5, and 10 mg L⁻¹) and temperatures (16, 22, and 28 °C) for 7 days to investigate the combined effects of MPs and simulated ocean warming by measuring different physiological parameters, such as cell growth, pigment contents (chlorophyll a and carotenoid), relative electron transfer rate (rETR), reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA), and adenosine triphosphate (ATP). The results demonstrated that MPs significantly decreased cell growth, pigment contents, and rETRₘₐₓ, but increased the MDA, ROS, and SOD levels for all MP treatments at low temperature (16 °C). However, high temperatures (22 and 28 °C) increased the pigment contents and rETRₘₐₓ, but decreased the SOD and MDA levels. Positive and negative effects of high temperatures (22 or 28 °C) were observed at low (1 and 5 mg L⁻¹) and high MP (10 mg L⁻¹) concentrations, respectively, indicating the antagonistic and synergistic effects of combined warming and MP pollution. These results imply that the effects of MPs on microalgae will likely not be substantial in future warming scenarios if MP concentrations are controlled at a certain level. These findings expand the current knowledge of microalgae in response to increasing MP pollution in future warming scenarios.

Particulate matter from wood burning emissions (Cwₒₒd) was quantified at five locations in the United Kingdom (UK), comprising three rural and two urban sites between 2009 and 2021. The aethalometer method was used. Mean winter Cwₒₒd concentrations ranged from 0.26 μg m⁻³ (in rural Scotland) to 1.30 μg m⁻³ (London), which represented on average 4% (in rural environments) and 5% (urban) of PM₁₀ concentrations; and 8% of PM₂.₅. Concentrations were greatest in the evenings in winter months, with larger evening concentrations in the weekends at the urban sites. Random-forest (RF) machine learning regression models were used to reconstruct Cwₒₒd concentrations using both meteorological and temporal explanatory variables at each site. The partial dependency plots indicated that temperature and wind speed were the meteorological variables explaining the greatest variability in Cwₒₒd, with larger concentrations during cold and calm conditions. Peaks of Cwₒₒd concentrations took place during and after events that are celebrated with bonfires. These were Guy Fawkes events in the urban areas and on New Year's Day at the rural sites; the later probably related to long-range transport. Time series were built using the RF. Having removed weather influences, long-term trends of Cwₒₒd were estimated using the Theil Sen method. Trends for 2015–2021 were downward at three of the locations (London, Glasgow and rural Scotland), with rates ranging from −5.5% year⁻¹ to −2.5% year⁻¹. The replacement of old fireplaces with lower emission wood stoves might explain the decrease in Cwₒₒd especially at the urban sites The two rural sites in England observed positive trends for the same period but this was not statistically significant.

Uncoupling chemical looping gasification (CLG), the organic sulfur evolution was simulated and explored qualitatively and quantitatively using typical sulfur compounds on TG-MS and temperature-programmed fixed bed. The HS radical in the reductive atmosphere easier converted to H₂S and COS. H₂O activated the evolution of S which was stably bonded to carbon, and H₂ generated from gasification and oxidation of reductive Fe by H₂O contributed to the release of sulfur. The proportion of H₂S released from sulfur compounds was greater than 87% in steam gasification, and more than 60% during CLG. Oxygen carriers promoted the conversion of sulfur to SO₂ in the mid-temperature region (500 °C–700 °C), and H₂S in the high temperature region (700 °C–900 °C). Sulfur species played a pivotal role in sulfur evolution at low temperature of CLG. The organic sulfur in mercaptan and benzyl were more easily converted and escaped than in thiophene and phenyl. The thermal stability of sulfur species, the presence of steam and OC affected the initial temperature and peak concentration of gas sulfur release as well as sulfur distribution. Consequently, CLG strengthened the sulfur evolution, and made it possible to targeted restructure the distribution of sulfur by regulating process parameters, or blending fuel with different sulfur species for emission reduction, and selective conversion of sulfur.

Inhalation of respirable silica particles can cause serious lung diseases (e.g., silicosis and lung cancer), and the toxicity of respirable silica is highly dependent on its crystal form. Common combustion processes such as coal and biomass burning can provide high temperature environments that may alter the crystal forms of silica and thus affect its toxic effects. Although crystalline silica (i.e., quartz, tridymite, and cristobalite) were widely found at different temperatures during the burning processes, the sources and crystal transformation pathways of silica in the burning processes are still not well understood. Here, we investigate the crystal transformation of silica in the coal and biomass combustion processes and clarify the detailed transformation pathways of silica for the first time. Specifically, in coal burning process, amorphous silica can transform into quartz and cristobalite starting at 1100 °C, and quartz transforms into cristobalite starting at 1200 °C; in biomass burning process, amorphous silica can transform into cristobalite starting at 800 °C, and cristobalite transforms into tridymite starting at 1000 °C. These transformation temperatures are significantly lower than those predicted by the classic theory due to possibly the catalysis of coexisting metal elements (e.g., aluminum, iron, and potassium). Our results not only enable a deeper understanding on the combustion-induced crystal transformation of silica, but also contribute to the mitigation of population exposure to respirable silica.

Multiwalled carbon nanotubes (MWCNTs) were oxidized using a mixture of H₂SO₄ and HNO₃, and the oxidized MWCNTS were decorated with magnetite (Fe₃O₄). Finally, poly-N-isopropyl acrylamide-co-butyl acrylate (P-NIPAM) was added to obtain P-NIPAM/Fe/MWCNT nanocomposites. The nanosorbents were characterized by various techniques, including X-ray diffraction, transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, and Brunauer–Emmett–Teller analysis. The P-NIPAM/Fe/MWCNT nanocomposites exhibited increased surface hydrophobicity. Owing to their higher adsorption capacity, their kerosene removal efficiency was 95%; by contrast, the as-prepared, oxidized, and magnetite-decorated MWCNTs had removal efficiencies of 45%, 55%, and 68%, respectively. The P-NIPAM/Fe/MWCNT nanocomposites exhibited a sorbent capacity of 8.1 g/g for kerosene removal from water. The highest kerosene removal efficiency from water was obtained at a process time of 45 min, sorbent dose of 0.005 g, solution temperature of 40 °C, and pH 3.5. The P-NIPAM/Fe/MWCNTs showed excellent stability after four cycles of kerosene removal from water followed by regeneration. The reason may be the increase in the positive charge of the polymer at pH 3.5 and the increased adsorption affinity of the adsorbent toward the kerosene contaminant. The pseudo second-order model was found to be the most suitable model for studying the kinetics of the adsorption reaction.