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Devine Sinclair posted an update 6 months, 4 weeks ago
Edible fungi residues are natural fungi etching feedstock that provide loose structure with multidimensional framework. These advantages help KOH to penetrate rigid cytoderm into innermost space and attain porous carbon with high porosity. Utilization of edible fungi residue not only avoids artificial operation of fungal inoculation and culture steps, but also provides new method for waste disposal. As expected, carbon derived from three fungi residues attains excellent porosity. The highest surface area reaches 3463.3 m2/g, which is approximately 2 and 6 times higher than original biomass (1630.7 m2/g) and commercial carbon (691.1 m2/g), respectively. Filiform structures derived from hyphae growth contribute to pores formation. Coprinus comatus fungi residue as optimal raw material obtains hierarchical pore channel with dominant micropores (76%) and natural nitrogen doping (1.28 at.%). The highest DCM and CB adsorption capacities attain 716.9 and 641.7 mg/g, respectively, which are 13 and 6 times higher than that of commercial carbon. The positive effects from fungi growth improve DCM adsorption particularly. DCM adsorption over fungi residues derived carbon is twice higher than original biomass carbon. Competitive adsorption, recyclability, surface variations and desorption components after saturated adsorption are fully investigated for practical application. The present study provides a new insight for developing high-value technology for synthesizing Cl-VOCs adsorbents using edible fungi residues. Smoldering wildfire in peatlands contributes significantly to global carbon emissions and regional haze events. Smoldering fire in peatlands is one of the largest and most persistent fire phenomena on Earth. Here we assess the underlying mechanism of rain in suppressing the smoldering peat fire in the shallow soil layer up to 15 cm deep through laboratory experiments. We show that the minimum rainfall intensity to extinguish the peat fire is roughly 4 mm/h, so that the persistent light rain cannot suppress such smoldering wildfire. The required rain duration, ∆t (min), for extinguishing smoldering peat fire decreases with the rainfall intensities, I (mm/h), as log10∆t = – 1.15log10I + 3.3, and is much longer than that for extinguishing flaming wildfire. We also identify that the required rainfall depth for extinguishing peat fire gradually decreases with the rainfall intensity and approaches a minimum value of 13 mm under violent rain. As rainfall intensity increases, the carbon emission flux from peat fire decreases. Therefore, we conclude that the short-term violent rain is most effective for suppressing the persistent smoldering peat fire. This research helps evaluate the impact of weather on the development of peat fire and improve the prediction of carbon emissions from peat fire with the use of regional weather models. The influence of common groundwater major ions on arsenic (As) retention by native limestones was studied through column experiments. Columns were packed with rock particles (0.5-1.41 mm) and fed with solutions containing As, and chloride (Cl), sulfate, bicarbonate or fluoride (F) in concentrations similar to those measured in one of the most As-rich wells of Mexico. Besides, other solutions were also treated containing multiples or submultiples of those anion concentrations. Physico-chemical parameters, As, and each anion concentrations were determined weekly along 4 months. After the end of the experiments rocks collected from the top of the columns were analyzed by XRF, XRD, and SEM-WDS. Concentrations of As decreased from 1.2 mg/L to values below the Mexican drinking water standard (0.025 mg/L), since the first week in the solutions containing F or Cl keeping low values afterwards, indicating that they do not interfere with As removal. However, although As strongly decreased in the solutions containing sulfate since the first week, it started to increase from the 12th week in the highest concentrated solution. Bicarbonate was the anion affecting most As retention, since, after its decrease below 0.025 mg/L in the 2nd week for both solutions (30 mg/L and 300 mg/L), it started to increase since the 7th week in the most concentrated one, but maintained a low concentration in the least concentrated solution. Saturation index calculations and XRD analyses did not evidence the formation of As minerals. However, SEM elemental maps and XRF analyses showed the presence of As on the rocks after the treatments. Results indicate that As may be retained by sorption. Sulfate and bicarbonate compete with As for sorption sites. Results showed that native limestones are an option for treating As polluted water. Experiments also indicated that bicarbonate and sulfate may interfere with As removal depending on their concentrations. Our study of 164 diatom samples from Catalonia (NE Spain) is the first to evaluate the applicability of DNA metabarcoding, based on high throughput sequencing (HTS) using a 312-bp rbcL marker, for biomonitoring Mediterranean rivers. For this, we compared the values of a biotic index (IPS) and the ecological status classes derived from them, between light microscope-based (LM) and HTS methods. Very good correspondence between methods gives encouraging results concerning the applicability of DNA metabarcoding for Catalan rivers for the EU Water Framework Directive (WFD). However, in 10 sites, the ecological status class was downgraded from “Good”/”High” obtained by LM to “Moderate”/”Poor”/”Bad” by HTS; these “critical” sites are especially important, because the WFD requires remedial action by water managers for any river with Moderate or lower status. We investigated the contribution of each species to the IPS using a “leave-one-out” sensitivity analysis, paying special attention to critical sites. Discrepancies in IPS between LM and HTS were mainly due to the misidentification and overlooking in LM of a few species, which were better recovered by HTS. Cyclosporine A nmr This bias was particularly important in the case of Fistulifera saprophila, whose clear underrepresentation in LM was important for explaining 8 out of the 10 critical sites and probably reflected destruction of weakly-silicified frustules during sample preparation. Differences between species in the rbcL copy number per cell affected the relative abundance obtained by HTS for Achnanthidium minutissimum, Nitzschia inconspicua and Ulnaria ulna, which were also identified by the sensitivity analysis as important for the WFD. Only minor IPS discrepancies were attributed to the incompleteness of the reference library, as most of the abundant and influential species (to the IPS) were well represented there. Finally, we propose that leave-one-out analysis is a good method for identifying priority species for isolation and barcoding.