Iron and Steel Industry Emissions: A Global Analysis of Trends and Drivers.

The iron and steel industry (ISI) is important for socio-economic progress but emits greenhouse gases and air pollutants detrimental to climate and human health. Understanding its historical emission trends and drivers is crucial for future warming and pollution interventions. Here, we offer an exhaustive analysis of global ISI emissions over the past 60 years, forecasting up to 2050. We evaluate emissions of carbon dioxide and conventional and unconventional air pollutants, including heavy metals and polychlorinated dibenzodioxins and dibenzofurans. Based on this newly established inventory, we dissect the determinants of past emission trends and future trajectories. Results show varied trends for different pollutants. Specifically, PM2.5 emissions decreased consistently during the period 1970 to 2000, attributed to adoption of advanced production technologies. Conversely, NOx and SO2 began declining recently due to stringent controls in major contributors such as China, a trend expected to persist. Currently, end-of-pipe abatement technologies are key to PM2.5 reduction, whereas process modifications are central to CO2 mitigation. Projections suggest that by 2050, developing nations (excluding China) will contribute 52-54% of global ISI PM2.5 emissions, a rise from 29% in 2019. Long-term emission curtailment will necessitate the innovation and widespread adoption of new production and abatement technologies in emerging economies worldwide.

A two-year water-stable 2D MOF with aqueous NIR photothermal conversion ability.

Structural lability in humid air or water severely limits the practical use of MOFs. Developing new MOFs with exceptional water stability is interesting for both industrial applications and academic research. Herein we report a new method to improve the water stability of MOFs by using three-dimensional rigid shielding ligands. A very highly stable two-dimensional MOF (CuCP-MOF) is synthesized in this work, in which [2,2]paracyclophane dicarboxylate ligands are coordinated with Cu(ii) ions to form a paddle wheel structure. CuCP-MOF is a triclinic crystal with unit cell parameters a = 10.065 Å, b = 10.897 Å, c = 10.940 Å, α = 90.676°, ß = 91.729°, and γ = 92.725° determined by single crystal X-ray diffraction and DFT simulation. It can easily form MOF nanosheets due to the large interlayer distance and weak interlayer interactions. It shows good aqueous stability, and remains intact after storage in water for two years, as evidenced by FTIR and XRD analyses. CuCP-MOF shows a strong absorption in the NIR range due to the d-d transition of Cu(ii). The aqueous dispersions of CuCP-MOF exhibit high NIR photothermal conversion efficiency, about 17.5% for a laser with an energy density of 5 W cm-2 (808 nm) and 22.0% for a laser of 2 W cm-2 on average.

Phototropic Aggregation and Light-Guided Long-Distance Collective Transport of Colloidal Particles.

Phoretic swarming and collective transport of colloidal particles in response to environmental stimuli have attracted tremendous interest in a variety of fields. In this work, we investigate the light-actuated motion, aggregation, and light-guided long-distance mass transport of silica microspheres in simple spiropyran solutions under the illumination of UV spot sources. The phototactic motion is confirmed by the dependence of swarming on the illumination intensity and spiropyran concentrations, ON-OFF switching tests, pattern-masked UV sources, etc. The aggregates formed via swarming of silica spheres can chase after a moving UV source, however, relying on a critical speed of the UV source. Only when the UV source speed is below the critical value, the aggregates follow the UV spot at a constant relative speed to the light spot. Analysis on the shape of silica microsphere currents indicates that continuous illumination of the UV spot source and resultant chemical gradients are important for the formation of steady microsphere currents. Light-guided aggregation and long-distance mass transport are interesting for targeted delivery and remote-controlled enrichment of environmental hazards.

A series of terpyridine-based zinc(ii) complexes assembled for third-order nonlinear optical responses in the near-infrared region and recognizing lipid membranes.

Two-photon (TP) microscopy has advantages for biological imaging in that it allows deeper tissue-penetration and excellent resolution compared with one-photon (OP) microscopy. Herein, two-photon activated nonlinear optical (NLO) materials, a terpyridine derivative ligand with a donor-acceptor (D-A) model and its corresponding four zinc(ii) complexes (Z1-Z4), were assembled and fully characterized. Based on their systematic photophysical investigations, it was found that the third-order NLO response in the near-infrared (NIR) region was significantly enhanced for the symmetrical complex Z4 compared with the other asymmetric complexes (Z1-Z3). To further explore its utility in biological systems, Z4 was selected as a two-photon probe for cellular lipid membranes, which was confirmed both by two-photon confocal microscopy and transmission electron microscopy (TEM). Furthermore, it was found that the fluorescence intensity was enhanced for complex Z4 with the addition of bioactive liposomes (1 µg mL-1). Its recognition mechanism was demonstrated by experimental methods, as well as molecular modeling calculations. These findings should open a new pathway for functional metal complexes as lipid membrane targeting probes.

Protective effects of betaglucin on myocardial tissue during myocardial infarction in rats and dogs.

AIM: To test the protective effects of betaglucin, a novel beta-glucan, on models of myocardial infarction (MI) in rats and dogs. METHODS: The left anterior descending (LAD) coronary artery occlusion model was used to induce an MI in rats and dogs. Three doses of betaglucin (10, 30 and 100 mg/kg), propranolol (positive control, 1 mg/kg) and vehicle alone (5% glucose solution) were administered before LAD occlusion, and characteristics of the resulting MI were subsequently assessed. In anesthetized dogs, blood pressure, heart rate, ventricular function, coronary artery blood flow and myocardial oxygen consumption were determined before and after the drug administration. RESULTS: The MI mass in both rats and dogs was significantly reduced by betaglucin (30 and 100 mg/kg, P<0.01) and propranolol (P<0.01). In anesthetized dogs, coronary artery blood flow was increased significantly by betaglucin (30 and 100 mg/kg, P<0.01), but blood pressure, heart rate and ventricular function were not changed (P>0.05). High-dose betaglucin (100 mg/kg) increased myocardial oxygen consumption, but not to a statistically significant level (P>0.05). The hemodynamic indexes were significantly changed by propranolol. CONCLUSION: Betaglucin has protective effects on myocardial tissue during MI in rats and dogs and has no influence on hemodynamic parameters at a therapeutic dose. The increase in coronary artery blood flow induced by betaglucin might be beneficial in the treatment of patients with MI.