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Chlorine peroxide reaction explains observed wintertime hydrogen chloride in the Antarctic vortex
No full textIt is well established that the drastic ozone loss in the Antarctic stratosphere, commonly known as the ozone hole, is primarily driven by gas-phase and heterogeneous chemical processes. While chemistry transport models generally reproduce observed ozone depletion well, they fail to capture the rapid early-winter decline of hydrogen chloride. We here examine the impact of the heterogeneous reaction between chlorine peroxide and hydrogen chloride forming HOOCl, followed by its photolysis. Incorporating this reaction and an additional hypochlorous acid loss pathway into a chemical mechanism significantly improves model agreement with observed levels of several chlorine compounds in the lower polar vortex stratosphere. This revised mechanism increases simulated ozone partial column depletion by over 15% between early July and mid-September 2011. Laboratory confirmation of these proposed reactions is needed to validate the mechanism
Emission dynamics of reactive oxygen species and oxidative potential in particles from a petrol car and wood stove
No full textTuning the electronic structure and SMSI by integrating trimetallic sites with defective ceria for the CO2 reduction reaction
No full textHeterogeneous catalysts have emerged as a potential key for closing the carbon cycle by converting carbon dioxide (CO2) into value-added chemicals. In this work, we report a highly active and stable ceria (CeO2)-based electronically tuned trimetallic catalyst for CO2 to CO conversion. A unique distribution of electron density between the defective ceria support and the trimetallic nanoparticles (of Ni, Cu, Zn) was established by creating the strong metal support interaction (SMSI) between them. The catalyst showed CO productivity of 49,279 mmol g−1 h−1 at 650 °C. CO selectivity up to 99% and excellent stability (rate remained unchanged even after 100 h) stemmed from the synergistic interactions among Ni-Cu-Zn sites and their SMSI with the defective ceria support. High-energy-resolution fluorescence-detection X-ray absorption spectroscopy (HERFD-XAS) confirmed this SMSI, further corroborated by in situ electron energy loss spectroscopy (EELS) and density functional theory (DFT) simulations. The in situ studies (HERFD-XAS & EELS) indicated the key role of oxygen vacancies of defective CeO2 during catalysis. The in situ transmission electron microscopy (TEM) imaging under catalytic conditions visualized the movement and growth of active trimetallic sites, which completely stopped once SMSI was established. In situ FTIR (supported by DFT) provided a molecular-level understanding of the formation of various reaction intermediates and their conversion into products, which followed a complex coupling of direct dissociation and redox pathway assisted by hydrogen, simultaneously on different active sites. Thus, sophisticated manipulation of electronic properties of trimetallic sites and defect dynamics significantly enhanced catalytic performance during CO2 to CO conversion
Organization of the macaque monkey insular cortex based on multimodal receptor architectonics
No full textSustainable resilient recycling partner selection for urban waste management: Consolidating perspectives of decision-makers and experts
No full textIn sustainable waste supply chains, selecting recycling partners is an important factor in the decision-making process. Waste supply chains have undergone many fundamental modifications because of the rise of concepts such as sustainability, circular economy, and resilience. To overcome the current shortcomings of the literature on recycling partner selection only based on sustainability aspects, an evaluation framework is developed to address recycling partner selection by considering both sustainability and resilience factors. Although developing a sustainable and resilient evaluation framework improves the process of selecting recycling partners, the problem becomes very complex, and multidimensional decision-makers require reliable and accurate tools to make informed decisions. Multi-criteria decision-making (MCDM) methods are useful decision-making tools with high reliability to address problems under uncertainty. Although previous studies have developed several MCDM methods based on various uncertainty sets, the capability to support efficient and accurate group decision-making by decision-makers’ opinions and experts’ judgments has been a major disadvantage. Therefore, this study develops a novel decision-making approach using Z-numbers based on the best-worst method (Z-BWM) and a combined compromise solution (Z-CoCoSo). The proposed novel approach for addressing a sustainability and resilience management problem in an urban setting is demonstrated in a real-life case study using Tabriz, Iran as a case study. According to the results, net profit and the robustness of the waste supply chain are the most important criteria
Effects of ball milling on biochar adsorption of contaminants in water: A meta-analysis
No full textReckless release of contaminants into the environment causes pollution in various aquatic systems on a global scale.Biochar is potentially an inexpensive and environmentally friendly adsorbent for removing contaminants fromwater. Ball milling has been used to enhance biochar's functionality; however, global analysis of the effect of ball millingon biochar's capacity to adsorb contaminants in aqueous solutions has not yet been done. Here, we conducted ameta-analysis to investigate the effects of ball milling on the adsorption/removal capacity of biochar for contaminantsin aqueous solutions, and to investigate whether ball milling effects are related to biochar production, ball milling, andother experimental variables. Overall, ball milling significantly increased biochar adsorption capacity towards both inorganicand organic contaminants, by 69.9%and 561.9%, respectively. This could be attributed to ball milling increasingbiochar surface area by 2.05-fold, pore volume by 2.39-fold, and decreasing biochar pH by 0.83-fold. The positiveadsorption effects induced by ball milling varied widely, with the most effective being ball milling for 12 to 24 h at 30
Tailoring doped organic nanoparticles as selective hole transporters for printed non-fullerene organic solar cells
No full textMost interface materials for organic solar cells (OSCs) were originally optimized for fullerene-based systems and are now being adapted for non-fullerene acceptor (NFA) based solar cells. This reliance on established interface materials results in a limited choice of interface materials for NFA based OSCs. For vacuum processed organic devices, the concept of doped interface materials is exceptionally successful, but has not yet been translated to modern NFA based devices due to solution processing constraints requiring orthogonal solubility. Herein, we report a novel concept for the development of solution-processed HTL in inverted n-i-p architecture OSCs using doped organic nanoparticles (D-NPs), overcoming solvent compatibility limitations and enabling scalable production processes. We demonstrate that the functional key interface properties of D-NPs HTLs can be tailored independently over a wide regime. Specifically, conductivity and work function can be optimized separately by varying the dopant concentration and the material system. By using D-NPs as HTL in the n-i-p architecture, power conversion efficiencies (PCE) of over 12 % are achieved for PM6:Y6 based devices. The D-NPs HTL concept is successfully applied to a variety of organic semiconductors used in photovoltaics and opens a new class of tailorable interface materials for solution-processed HTL materials